Dissertations / Theses: 'Plant mites'

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Pauw, Anton. "Mite-plant mutualism: leaf domatia of African plants house beneficial mites." Thesis, University of Cape Town, 1992. http://hdl.handle.net/11427/25735.

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Cruz, Miralles Joaquín. "Plant defense responses induced by phytoseiid predatory mites." Doctoral thesis, Universitat Jaume I, 2019. http://hdl.handle.net/10803/667321.

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The ability of phytoseiids for inducing plant defensive responses was studied. First, the activation of citrus defense pathways in two rootstocks with different resistance to Tetranychus urticae, Citrus aurantium and C. reshni, was analysed. Metabolomic analyses showed that the jasmonic acid, salicylic acid and flavonoids defense pathways were modified depending on plant genotype and phytoseiid diet specialization. Second, attraction and repellence of volatiles released by citrus infested by phytoseiids was studied. This depended on the species of the predator triggering these responses. We also carried out choice tests without plants and observed that phytoseiids were repellent for T. urticae. Furthermore, the volatiles released by each phytoseiid were characterized and included different organic compounds from green leaf volatiles to monoterpenes. Finally, the reproduction of the three phytoseiids when feeding on T. urticae obtained from two different rootstocks was studied. We concluded that phytoseiids can induce different plant defensive responses.
Esta tesis estudia la capacidad de los fitoseidos para inducir respuestas defensivas en cítricos. Primero, estudiamos la activación de las rutas de defensa para dos patrones con diferente resistencia a Tetranychus urticae, Citrus aurantium y C. reshni. Los análisis metabolómicos muestran que las rutas del ácido jasmónico, ácido salicílico y flavonoides se modificaron en función del genotipo de la planta y de la dieta del fitoseido. En cuanto a resultados de atracción y repelencia de cítricos infestados por fitoseidos, el comportamiento dependió del fitoseido inductor. En ensayos de elección sin planta se observó que los fitoseidos son repelentes para T. urticae. Además, se caracterizaron los volátiles liberados por los fitoseidos, mostrando diferentes compuestos orgánicos, desde volátiles verdes de planta hasta monoterpenos. Finalmente, analizamos la reproducción de los depredadores cuando se alimentan de araña procedente de distinto patrón. Concluimos que los fitoseidos pueden inducir respuestas defensivas en las plantas.

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O'Connell, Dean Michael, and n/a. "Plant-arthropod interactions : domatia and mites in the genus Coprosma (Rubiaceae)." University of Otago. Department of Botany, 2009. http://adt.otago.ac.nz./public/adt-NZDU20090807.160026.

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Plant-based defence mutualisms involve aspects of plant morphology that influence the performance of plant parasites, their natural enemies and trophic interactions. Leaf domatia, small indentations on the underside of leaves, can be structurally complex, and are often inhabited by potentially beneficial mites and other arthropods. Plant morphological traits such as domatia that enhance mutualistic relationships may result in increased plant growth rates, and reproductive success. New Zealand supports ~60 plant species that have domatia, the most speciose genus being Coprosma. The aim of this thesis was to examine factors that affect the production of leaf domatia and their relationship with foliar mite assemblages. The three main objectives of this thesis are: First, to investigate the production of foliar domatia and their susceptibility to limited resources, particularly to carbon availability. Second, to test if domatia are inducible structures during leaf ontogeny in the presence of foliar mites and/or fungi. Finally, to explore the effect of domatia availability on foliar mite assemblages on leaves with and without resident mites. This thesis tested the stated objectives using C. lucida, C. ciliata, C. foetidissima and C. rotundifolia, with a combination of field investigations and controlled manipulative experiments. The cost of domatia production was investigated using two field surveys and two controlled experiments. Under natural conditions the relationship between leaf morphology and domatia were measured in situ and across an altitudinal gradient. The experimental manipulations used carbon and nutrient stress, induced by temperature, light and fertilizer application. The second objective was experimentally tested under field conditions by manipulating foliar mites and fungal densities on C. rotundifolia. The third objective was investigated by manipulating domatia availability on C. lucida shrubs across three different vegetation types. Under field conditions, the number of domatia per leaf was associated with leaf morphology in C. lucida and C. foetidissima, but not C. rotundifolia. Foliar carbon showed a positive, but weak association with domatia production in C. foetidissima and C. ciliata. Altitudinal induced-carbon stress on domatia production was ambiguous. Domatia production in C. foetidissima was positively associated to altitude in field survey (1), and negatively associated in the second survey, with no correlation found between carbon and altitude. Experimental C. rotundifolia shrubs held under elevated night-time temperatures showed a 2.5 fold increase in respiration, a 34% to 91% decrease in daily carbon gain, and 38% decrease in domatia per leaf mass. Domatia production showed no significant differences under nutrient stress. The results showed little evidence to support a role for induction of domatia. Domatia production in new leaves was similar across all experimental treatments. Diverse vegetation types supported 60% higher mite species. Leaves with domatia supported ~22 to 66% higher mite densities, greater colonisation success and more diverse mite assemblages, than those without domatia. In the pastoral vegetation, the absence of predatory mites on experimental shrubs resulted in no differences in fungivorous mite densities regardless of domatia availability. Plant investment in foliar domatia appears associated with the number of available sites on the leaf under field conditions. The role of carbon availability during leaf ontogeny suggests a complex and highly variable association with domatia production. Domatia are constitutive defence structures that influence mite assemblages, mediating both beneficial and antagonistic relationships. This thesis concludes that domatia are in part, carbon-based non-inducible structures that influence mite assemblages, plant-mite and mite-mite interactions, and increase the probability of successful colonisation.

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Maeda, Taro. "Foraging behavior of predacious phytoseiid mites using herbivoreinduced plant volatiles." Kyoto University, 2001. http://hdl.handle.net/2433/150345.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(農学)
甲第9179号
農博第1212号
新制||農||834(附属図書館)
学位論文||H13||N3591(農学部図書室)
UT51-2001-N225
京都大学大学院農学研究科地域環境科学専攻
(主査)教授高藤晃雄, 教授西岡孝明, 教授藤崎憲治
学位規則第4条第1項該当

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Van, der Walt Lene. "Characterisation of mites and peniciccium species associated with apple core rot diseases." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/4056.

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Thesis (MSc (Plant Pathology))--University of Stellenbosch, 2009.
ENGLISH ABSTRACT: Dry core rot (DCR) and wet core rot (WCR) are among some of the most important postharvest diseases of apples in South Africa. Mouldy core (MC) is also a symptom associated with the core region of apples, but it is not of economical importance since apple tissue surrounding the core region is not affected as is the case with DCR and WCR. The incidence of core rots in harvested fruits can be as high as 12%, but in general ranges from 3 to 8%. Infections and losses can also occur during fruit handling in pack houses and during storage. Additionally, yield losses also occur prior to harvest within orchards due to premature fruit drop of core rot affected fruits. The incidence of core rot diseases in apples differ among apple cultivars, with most Red Delicious varieties being susceptible to the development of core rots, whereas core rots have rarely been reported in other cultivars such as Granny Smith. The etiology and epidemiology of WCR and DCR are poorly understood. Although many fungal genera have been associated with the diseases, small-spored Alternaria species are mainly associated with DCR, whereas Penicillium species including P. roquefortii, P. expansum and P. funiculosum have mainly been associated with WCR. Dry core rot infections have long been known to occur pre-harvest, whereas WCR is primarily known as a post-harvest disease where infections take place during fruit handling in pack houses. Recently, Tarsonemus mites have also been indicated as being a potential role player in the etiology of core rot diseases. The mites have been hypothesised to carry pathogen spores into the core region of apples, and they may also possibly cause small wounds that facilitate pathogen entry. In South Africa, apple growers have recently reported WCR as being present prior to harvest, which has not been reported previously. Therefore, the first aim of the study was to investigate the incidence, as well as the causal agent/s of pre-harvest WCR. The incidence of WCR ranged from 0% to 1.7% in eleven orchards, and was in general lower than that of DCR (0.4% to 6%). Isolation studies from eight internal positions in WCR apples showed that Penicillium was the predominant fungal genus in most of the positions, including the lesion area. Morphological and molecular characterisation of Penicillium isolates from WCR showed that P. 2 ramulosum prov. nom. was the main species isolated from lesions, as well as other isolation positions. However, this species was also the main species isolated from DCR, MC and asymptomatic apples. Penicillium expansum was only isolated at low frequencies from WCR and DCR apples. Other Pencillium species that were occasionally isolated included P. glabrum, P. chloroloma, P. chermisinum and a putative new species with closest affinity to P. dendriticum (P. species aff. dendriticum) on a DNA nucleotide sequence basis. Pathogenicity and virulence studies using three different inoculation methods showed that P. expansum was the most virulent species, followed by P. species aff. dendriticum. The P. ramulosum prov. nom. isolates varied in their virulence, but were all considered to have low virulence. The role of Tarsonemus mites in the etiology and epidemiology of core rot diseases is poorly understood, and therefore the second aim of the study was to investigate some of these aspects. The specific aims of the study were to (1) investigate the ecology of Tarsonemus mites in Red Delicious and Granny Smith orchards during different apple developmental stages, (2) determine if there is a significant association of Tarsonemus mites with diseased (WCR and DCR) fruits and (3) determine if potential core rot pathogenic fungi are associated with the mites. Tarsonemus mites were found in all of the investigated apple developmental stages (buds, blossoms, 4cm diameter fruit, mature fruit and mummies), having the highest incidence in mummies and mature fruits from Red Delicious and Granny Smith orchards. In Red Delicious fruits the Tarsonemus mites were found within the core and/or calyx tube, whereas in Granny Smith fruits the mites were restricted to the calyx tube. In Red Delicious fruits there was a significant association between dry core rot as well as total core rot (wet- and dry-core rot) with the presence of mites in the core, as well as total mites (mites in core and calyx tubes). Fungal isolation studies from the Tarsonemus mites showed that they carried potential core rot fungal pathogens within the genera Penicillium and Alternaria. The Penicillium species isolated from the mites included two of the most virulent WCR species, P. expansum and P. species aff. dendriticum.
AFRIKAANSE OPSOMMING: Droë kernvrot and nat kernvrot is van die belangrikste na-oes siektes van appels in Suid- Afrika. Beskimmelde kern word ook met die kern van appels geassosieer, maar hierdie toestand is egter nie van ekonomiese belang nie, aangesien die weefsel rondom die kern nie geaffekteer word soos in die geval van nat- en droë kernvrot nie. Die voorkoms van kernvrot in vrugte na oes, kan vlakke van tot 12% bereik, maar oor die algemeen is die voorkoms tussen 3 en 8%. Infeksie en verliese kan ook voorkom gedurende die hantering en verpakking van vrugte in pakhuise en gedurende storing. Addisionele verliese in opbrengs kan ook voor-oes voorkom in boorde. Dit is te wyte aan voortydige vrugval van appels wat besmet is met kernvrot. Die voorkoms van kernvrot by appels verskil tussen kultivars. Meeste van die “Red Delicious” variëteite is vatbaar vir die ontwikkeling van kernvrot. Die toestand is egter skaars by ander kultivars soos Granny Smith. Die etiologie en epidemiologie van nat- en droë kernvrot word nie goed verstaan nie. ‘n Groot aantal swamgenera is al met kernvrot geassosieer. Klein-spoor Alternaria spesies word hoofsaaklik met droë kernvrot geassosieer en Penicillium spesies, insluitende P. roquefortii, P. expansum en P. funiculosum, word meestal met nat kernvrot geassosieer. Dit is lank reeds bekend dat droë kernvrot as voor-oes siekte kan voorkom, maar nat kernvrot is algemeen bekend as na-oes siekte waar infeksie tydens vrughantering en verpakking plaasvind. Daar is onlangs aangedui dat Tarsonemus myte potensiële rolspelers in die etiologie van kernvrot is. Hipoteties is die myte in staat om spore van die patogene in die kern van die appels in te dra, asook om klein wonde te veroorsaak wat infeksie deur patogene vergemaklik. In Suid-Afrika is nat kernvrot wat voor-oes in die boorde ontstaan onlangs deur boere aangemeld; hierdie toestand is nog nie op ‘n vorige geleentheid aangemeld nie. Die eerste doelwit van hierdie studie was dus om die voorkoms en veroorsakende organisme/s van voor-oes nat kernvrot te ondersoek. Die voorkoms van nat kernvrot was tussen 0 en 1.7% in elf boorde en was oor die algemeen laer as die voorkoms van droë kernvrot (0.4 tot 6%). Isolasiestudies uit agt interne posisies van nat kernvrot appels het getoon dat Penicillium die dominante swamgenus in die meeste posisies was, insluitend die letsels. Morfologiese en molekulêre karakterisering van 4 Penicillium isolate uit nat kernvrot letsels het aangedui dat P. ramulosum prov. nom. die spesie is wat die meeste geïsoleer is vanuit die letsels, asook ander isolasie posisies. Dié spesie was egter ook die mees algemene spesie wat uit nat- en droë kernvrot, asimptomatiese appels en appels wat slegs swamgroei in die kern gehad het, geïsoleer is. Penicillium expansum was ook in lae getalle uit nat- en droë kernvrotletsels geïsoleer. Ander Penicillium spesies wat ook soms geïsoleer is, sluit P. glabrum, P. chloroloma, P. chermisinum, asook ‘n moontlik nuwe spesie wat op DNA volgorde basis die naaste aan P. dendriticum (P. spesie aff. dendriticum) is. Studies wat patogenesiteit en virulensie van die isolate ondersoek het, is ook uitgevoer deur gebruik te maak van drie verskillende inokulasie metodes. Die studies het aangedui dat P. expansum die mees virulente spesie is, gevolg deur P. spesie aff. dendriticum. Die P. ramulosum prov. nom. isolate het variasie in virulensie getoon maar is oor die algemeen aanvaar om minder virulent te wees. Die rol van Tarsonemus myte in die etiologie en epidemiologie van kernvrot word nie goed verstaan nie en dus was die tweede doelwit van die studie om sommige van dié aspekte te ondersoek. Die spesifieke doelwitte was (1) om die ekologie van die Tarsonemus myte in “Red Delicious” en Granny Smith boorde tydens verskillende ontwikkelingstadiums van die appels te ondersoek, (2) om te bepaal of daar ‘n betekenisvolle assosiasie van Tarsonemus myte met siek (nat- en droë kernvrot) vrugte bestaan en (3) om te bepaal of potensiële kernvrot patogeniese swamme geassosieer is met die myte. Tarsonemus myte is gevind in al die ontwikkelingstadiums (knoppies, bloeisels, 4 sentimeter deursnee vrugte, volwasse vrugte en mummies) van appels wat ondersoek is. Die hoogste voorkoms van myte was in die mummies en volwasse vrugte van “Red Delicious”, asook Granny Smith kultivars gevind. In “Red Delicious” vrugte is myte in die kern en/of kaliksbuis gevind, maar in die Granny Smith vrugte was die myte tot die kaliksbuis beperk. In “Red Delicious” vrugte was daar ‘n betekenisvolle assosiasie tussen droë kernvrot, asook totale kernvrot (nat en droë kernvrot) met die teenwoordigheid van myte in die kern, asook totale myte (myte in die kern en kaliksbuis). Swam isolasiestudies vanaf die Tarsonemus myte het aangetoon dat potensiële kernvrot swampatogene in die genera Penicillium en Alternaria wel by die myte teenwoordig was. Die Penicillium spesies wat vanaf die myte geïsoleer is het twee van die mees virulente nat kernvrot spesies ingesluit, nl. P. expansum en P. spesie aff. dendriticum.

6

Smith, Ian A. "The effects of two foraging traits on within-plant foraging efficiency of Phytoseiulus persimilis (Acari: phytoseiidae)." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/8632.

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Master of Science
Department of Entomology
David C. Margolies
James R. Nechols
Many crops grown in greenhouses are damaged by the twospotted spider mite, Tetranychus urticae. The predatory mite, Phytoseiulus persimilis, is a commercially-available predator that is commonly used to control twospotted spider mites on greenhouse crops; but its efficacy varies among crops, and it is generally ineffective at low prey densities. In general, predator foraging efficiency depends on how well predators find prey patches, the length of stay in prey patches, and consumption of prey while in prey patches. With respect to P. persimilis, I asked how this predator responds to different prey distributions, as might be encountered at different stages of spider mite infestations. I also asked how components of foraging, namely consumption rate and dispersal tendency, affected predator efficiency. To examine the former, I established T. urticae eggs on 6-leafed cucumber plants in two distributions. To examine the latter, I imposed artificial selection on a population of P. persimilis to create a line that exhibited extremely high consumption and one that demonstrated a greater tendency for dispersal. Subsequently, foraging efficiency was assessed by observing predator oviposition and consumption of twospotted mite eggs on individual leaves of 6-leafed cucumber plants. The number of eggs laid by predators corresponded to the number of prey consumed regardless of predator line. In addition, predators from both lines distributed their eggs proportional to where they fed. However, prey consumption differed between selected lines in response to prey distribution. Predators selected for high consumption fed more on the basal leaf where they were released; whereas prey consumption by the high dispersal and control lines were more evenly distributed throughout the plant. These results contribute to a better understanding of how foraging behavior is modified in plant landscapes under different levels of expression of foraging traits. They also indicate that predator release strategies likely would need to modified in accordance with the kind of foraging trait(s) used in artificial selection programs. In general, my research, when combined with future studies at a broader landscape level, will facilitate decisions by biological control practitioners about whether changes in foraging efficiency resulting from artificial selection justify the cost investment of producing selected lines of P. persimilis

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Ruckert, Alice. "Interactions Between Plant Water-Stress and Neonicotinoid Insecticides on Spider Mite Infestations in Corn." DigitalCommons@USU, 2017. https://digitalcommons.usu.edu/etd/6428.

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Spider mites (Acari: Tetranychidae) are an important agricultural pest of many crops and landscape plants. They can reproduce rapidly and quickly develop resistance to many pesticides, making them difficult to manage. Plant water-stress and high temperatures promote spider mite infestations, while spider mite outbreaks can also result from neonicotinoid insecticide applications. Drought is predicted to increase in the Intermountain West due to increases in temperature and reduced frequency of precipitation events in the region, and neonicotinoids are currently one of the most widely used classes of insecticides in field crops. I studied the interactive effect of these two simultaneously occurring abiotic factors on spider mite outbreaks and plant biosynthesis of herbivore-related defense proteins. I also evaluated ways to alleviate spider mite outbreaks with drought-tolerant corn and the exogenous application of plant phytohormones involved in plant resistance toward biotic stressors. I found that plant water-stress increased spider mites and that neonicotinoids exacerbated the effect of water-stress. Although applications of plant hormones did not reduce the effect of water-stress and neonicotinoids, drought tolerant corn showed promise in reducing the effect of water-stress and spider mite outbreaks.

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Cruz, Fredy Alexander Rodríguez. "Biological control of broad mites in chili pepper and physic nut." Universidade Federal de Viçosa, 2014. http://locus.ufv.br/handle/123456789/931.

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O ácaro-branco Polyphagotarsonemus latus (Banks, 1904) (Acari: Tarsonemidae) é uma praga chave de distribuição mundial que ataca várias espécies de plantas de alto valor econômico. No Brasil, este ácaro é considerado praga chave da cultura de pimenta malagueta e do pinhão manso, devido a sua frequente ocorrência em areas produtoras e aos danos causados. Na maioria das vezes seu controle é baseado na aplicação de produtos químicos, com todos os problemas derivados de seu uso abusivo. Uma alternativa ao controle químico é o uso do controle biológico. Os principais inimigos naturais dos ácaros fitófagos são ácaros da família Phytoseiidae. Vários inimigos naturais hão sido registrados em associação com o ácaro-branco no Brasil, os fitoseídeos (Amblyseius herbicolus, Neoseiulus barkeri, Euseius concordis, Iphiseiodes zuluagai and Typhlodromus transvaalensis) e uma espécie da família Blattisociidae (Lasioseius floridensis). Como um primeiro passo para a seleção de agentes de controle biológico para o ácaro-branco, foram avaliadas as taxas de predação e oviposição das espécies A. herbicolus, N. barkeri e L. floridensis em duas situações: uma mistura dos estádios do ácaro-branco e em todos os diferentes estádios da praga. Num segundo passo, foi avaliado em condições de casa de vegetação, a eficiência dos fitoseídeos, A. herbicolus e N. barkeri, no controle do ácaro branco em pimenta malagueta em diferentes relações predador: presa. Num segundo experimento, foi avaliado o controle em plantas de pimenta malagueta infestadas com o ácaro-branco, com e sem liberação de predadores e seu impacto na produção de frutos. Um terceiro passo, foi avaliado o controle do ácaro- branco em plantas de pinhão manso e pimenta malagueta infestadas artificialmente com a praga em condições de campo, com e sem liberação dos fitoseídeos e seu efeito na produção da pimenta malagueta. Nos experimentos de laboratório, os fitoseídeos predaram e ovipositaram quando se usou a mistura dos estádios do ácaro-branco e em cada um dos estádios. Amblyseius herbicolus apresentou uma maior taxa de predação e oviposição, nas duas situações avaliadas em comparação a N. barkeri. Entretanto, L. floridensis apresentou taxas de predação e oviposição baixas ou nulas nas duas situações avaliadas. Em casa de vegetação, A. herbicolus e N. barkeri controlaram as populações do ácaro-branco nas diferentes relações predador:presa; as plantas controle mostraram sintomas de um ataque severo sete dias após a infestação, incluindo a queda de folhas. No segundo experimento, os fitoseídeos mantiveram baixas as populações de ácaro-branco através do tempo. Assim mesmo, as plantas de pimenta malagueta com presença dos predadores apresentaram um maior número de frutos com maior peso do que as plantas controle. As plantas controle exibiram danos severos, incluindo queda de folhas. Em condições de campo, plantas de pinhão manso sem predadores exibiram altíssimas populações do ácaro-branco, sintomas severos, queda de folhas e altos valores na escala de notas de dano. Entretanto, plantas com predadores mostraram baixas populações da praga ao longo do tempo e não manifestaram sintomas severos. Em pimenta malagueta, as plantas sem predadores apresentaram maior número de ácaros-branco, curvamento e bronzeamento das folhas, porém a queda de folhas foi muito menor que registrada no experimento de casa de vegetação. Plantas de pimenta malagueta com presença de predadores exibiram baixo número de ácaros-branco e não apresentaram bronzeamento nem queda de folhas. Não houve diferença estatística no número e peso de frutos entre plantas de pimenta malagueta com e sem predadores, mas as plantas controle apresentaram frutos mais pequenos. Os predadores A. herbicolus e N. barkeri, foram efetivos no controle de populações do ácaro-branco nos diferentes passos avaliados neste estudo. As duas espécies predaram e ovipositaram ao se alimentar da praga. Em condições de casa de vegetação as plantas de pimenta malagueta foram beneficiadas pela presença dos predadores apresentando baixas populações da praga através do tempo, resultando na produção de frutos maiores e mais pesados. Em campo, os dois fitoseídeos tiveram a capacidade de manter em baixas densidades as populações do ácaro- branco no tempo, tanto em pinhão manso quanto em pimenta malagueta evitando o aparecimento de sintomas severos como os registrados nas plantas controle. Amblyseius herbicolus e N. barkeri podem ser considerados bons agentes de controle biológico do ácaro-branco. As duas espécies controlaram populações da praga em diferentes relações predador:presa, em condições de cultivo protegido e no campo. Os predadores conseguiram-se manter e aumentar em número no tempo, tanto em casa de vegetação quanto no campo, confirmando os resultados de laboratório. Adicionalmente, os predadores conseguiram aumentar seu número em baixas densidades de ácaro-branco, indicando que eles podem fazer uso de recursos alternativos como o pólen ou néctar das flores de pimenta malagueta. O potencial de controle destes fitoseídeos pode ser aproveitado em outras culturas susceptíveis ao ataque do ácaro-branco, como papaia, feijão, batata ou gérbera, tanto em casa de vegetação quanto em campo aberto.
The broad mite Polyphagotarsonemus latus (Banks 1904) is an important worldwide pest, with economic impact of several crops. In Brazil, this mite is considered a key pest of chili pepper and physic nut, due to their frequent occurrence in planting areas and damage caused to plant hosts. Its control is based on application of agrotoxics with several problems derived from misuse. An alternative to chemical control is biological control. The main natural enemies of phytophagous mites are predatory mites from the phytoseiidae family. Several natural enemies have been recorded in association with broad mites in Brazil, including the phytoseiids (Amblyseius herbicolus, Neoseiulus barkeri, Euseius concordis, Iphiseiodes zuluagai and Typhlodromus transvaalensis) and one blattisociid mite species (Lasioseius floridensis). As a first step to select biological control agents for broad mites, we evaluated the predation and oviposition rates of predatory mite of species A. herbicolus, N. barkeri and L. floridensis on a mixture of broad mite stages and on all different stages of the pest. As a second step, we evaluated under greenhouse conditions the phytoseiids A. herbicolus and N. barkeri on chili pepper with different predator:prey ratios. In a second experiment, we evaluated the control on chili pepper plants infested with broad mites, with and without predators and their impact on fruit production. In a third step, we assessed the control of broad mites on physic nut and chili pepper plants, artificially infested with the pest, under field conditions with and without phytoseiids and their effect on the chili pepper production. In laboratory experiments, the phytoseiids preyed and oviposited when offered a mix of broad mite stages or on each stage separately. Amblyseius herbicolus showed higher predation and oviposition rates on the mix of broad mite stages and on each stage separately compared with N. barkeri rates. Meanwhile, L. floridensis showed oviposition and predation rates low or zero on the mix of broad mite stages and on each stage separately. In the greenhouse, A. herbicolus and N. barkeri controlled broad mite population in the different predator:prey ratios; control plants showed symptoms of a severe attack seven days after infestation, including foliar abscission. In a second experiment, the phytoseiids maintained the broad mite populations at low density over time. Chili pepper plants with predators had a higher number of fruits with greater weight that control plants. Control plants showed higher values on scale notes of injury with severe damage, including foliar abscission. Under field conditions, physic nuts and chili peppers without predators showed a very high population of broad mites with higher values on scale notes of injury. These plants showed severe symptoms and foliar abscission. However, plants with predators showed a low population of pest through time with low values on scale notes of injury without presence of severe symptoms. In chili pepper, plants without predators had higher number of broad mite, curling and bronzing of leaves, but leaf fall was much lower than recorded in the greenhouse experiments. Chili pepper plants with predators showed low number of broad mites and showed no symptoms. There was no statistical difference in the number and weight of fruits from chili pepper plants with and without predators, but control plants had smaller fruits. The predators A. herbicolus and the Brazilian strain of N. barkeri showed effectivess in controlling broad mite populations on the different steps evaluated in this study. Both predators preyed and oviposited when feeding on the pest. Under greenhouse conditions, chili pepper plants were benefited by presence of predators, showing low populations of broad mites through time, resulting in the production of larger fruits with higher weight. In field, both phytoseiids had the ability to maintain broad mite populations on low density through time on physic nut and chili pepper plants, preventing the development of severe symptoms in the plants. Amblyseius herbicolus and N. barkeri can be considered good biological control agents of the broad mite. Both species controled pest populations with different predator:prey ratios in protected cultivation and in the field. Predators were able to maintained and increased on number through time when fed on broad mite, confirming the laboratory results. The potential of control of A. herbicolus and N. barkeri can be exploited in other crops susceptible to broad mite attack as bean, papaya, potato or gerbera, both on the greenhouse and open field conditions.

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Junqueira, Barbara Rodrigues. "Diversidade de ácaros edáficos em um fragmento de mata atlântica e três cultivos agrícolas, em Jaboticabal/SP, com ênfase nos Gamasina (Mesostigmata)." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/152291.

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No Brasil, os estudos que visam avaliar a diversidade e abundância de ácaros edáficos predadores, como os Gamasina (Mesostigmata), ainda são incipientes, focando principalmente em áreas de vegetação natural. No entanto, compreender o impacto da agricultura nestes organismos é importante no aspecto de preservar a biodiversidade e avaliar a sensibilidade destes indíviduos aos tratos culturais. Além disso, conhecer a diversidade desses ácaros edáficos é o primeiro passo na prospecção de novos agentes de controle biológico. Dessa forma, o objetivo dessa dissertação foi determinar e comparar a diversidade e abundância de espécies de ácaros edáficos presentes em um fragmento de Mata Atlântica e em três cultivos agrícolas, em Jaboticabal, estado de São Paulo, com ênfase nos Gamasina. As coletas de solo e serrapilheira (quando presente) foram realizadas bimenstralmente, entre os meses de agosto de 2015 a junho de 2017. Foram avaliadas quatro áreas: um fragmento de Mata Atlântica e cultivos de milho, soja e mangueiras. Cada coleta consistiu em 10 pontos amostrais aleatórios. No laboratório, as amostras foram colocadas em equipamento do tipo Funil de Berlese-Tullgren modificado para extração dos ácaros. O material extraído foi triado, os ácaros foram separados por ordem, sendo os Gamasina montados em lâminas de microscopia. Em seguida, os Gamasina foram identificados, sempre que possível, até o nível de espécie. Os resultados deste estudo demonstraram que o grupo de ácaros edáficos mais abundante, para as quatro áreas de coleta, foi Oribatida (Sarcoptiformes), representando 73,5% dos ácaros coletados. Os Gamasina foram o segundo grupo mais encontrado (19%). Dentre os Gamasina foram encontradas 12 famílias, 35 gêneros e 50 morfoespécies, com destaque para Ologamasidae, representando 33,9% dos Gamasina coletados, seguida de Blattisociidae (18,3%), Laelapidae (13,2%) e Phytoseiidae (11,8%). No fragmento de vegetação natural foram coletados cerca de 52% dos Gamasina, com 25% no cultivo de mangueira, 19% na soja e 4% no milho. A área de vegetação natural também foi a que apresentou maior diversidade de gêneros e morfoespécies seguido pelo cultivo de mangueiras, soja e milho. Nesse estudo também foram encontradas novas espécies para ciência e até um novo gênero, Ologamasidae n. gen. n. sp., que é descrito baseado na morfologia de fêmeas e machos adultos coletados no fragmento de Mata Atlântica. Esse estudo demonstra que o impacto da ação antrópica afeta a comunidade de ácaros edáficos qualitativa e quantitativamente, ou seja, nas áreas de cultivo agrícola obteve-se menor diversidade e abundância de Gamasina.
In Brazil, studies aimed to evaluate the diversity and abundance of edaphic predatory mites, such as the Gamasina (Mesostigmata), are still incipient, focusing mainly on areas of natural vegetation. However, understanding the impact of agriculture on these organisms is important in terms of preserving biodiversity and assessing the sensitivity of these individuals to agricultural managements. In addition, knowing the diversity of these soil mites is the first step in prospecting for new biological control agents. Thus, the objective of this study was to determine and compare the diversity and abundance of edaphic mite species present in a fragment of Atlantic Forest and three agricultural crops, in Jaboticabal, state of São Paulo, with an emphasis on Gamasina. Soil and litter (when present) were collected bi-monthly, between August 2015 and June 2017. Four areas were evaluated: a fragment of Atlantic Forest, corn, soybean and mango crops. Each sample consisted on ten random sampling points. In the laboratory, the samples were placed in a modified Berlese-Tullgren funnel for the extraction of mites. The extracted material was screened and the mites were separated in order, the Gamasina being mounted on microscopic slides. Then were identified, when possible, to species level. The results of this study showed that Oribatida (Sarcoptiforme) was the most abundant mite collected, representing 73.5% of total miltes, for the four areas. Gamasina were the second most abundant group (19%). Among the Gamasina, 12 families, 35 genera and 50 morphospecies were found, mainly Ologamasidae, representing 33.9% of the Gamasina collected, followed by Blattisociidae (18.3%), Laelapidae (13.2%) and Phytoseiidae (11, 8%). In the natural vegetation fragment, about 52% of the Gamasina were collected, 25% in mango culture, 19% in the soybean area and 4% in the corn area. The area of natural vegetation was also the one that presented greater diversity of genera and morphospecies followed by the cultivation of mango, soybean and corn. In this study new species were also found for science and even a new genus, Ologamasidae n. gen. n. sp., which is described based on the morphology of adult females and males collected in the Atlantic Forest fragment. This study demonstrates that the impact of anthropic action affects the community of soil mites qualitatively and quantitatively, that is, in the agricultural cultivation areas, there was less diversity and abundance of Gamasina.
134530/2015-2

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Oliveira, Daniel Chiaradia. "Níveis de ocorrência do ácaro Aceria guerreronis Keifer e de outros ácaros (Acari) a este associados no estado de São Paulo." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-09022011-102411/.

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O ácaro Aceria guerreronis Keifer representa uma das principais pragas da cultura do coqueiro em diversos países. Colônias deste ácaro, também designado de ácaro-do-coqueiro, são encontradas principalmente sob as brácteas dos frutos jovens, onde se alimentam de tecidos meristemáticos, freqüentemente causando queda prematura de frutos. O objetivo deste trabalho foi estimar os níveis de ocorrência de A. guerreronis e de outros ácaros a ele associados, para se avaliar o possível papel dos ácaros predadores no controle deste ácaro. Amostras foram coletadas em julho e dezembro de 2009 e abril de 2010 de 2 plantios de cada um dos seguintes municípios do Estado de São Paulo: Cedral, Mirandópolis, Riolândia e Tupã (região noroeste), e Peruíbe (litoral). Em cada campo, cada amostra consistiu de 10 frutos jovens, 30 folíolos e 5 espiguetas de inflorescência, tomados de cada uma de 5 plantas; além disso, até 10 frutos abortados foram também coletados de cada campo, quando presentes. Foram encontrados ácaros em todas as estruturas vegetais amostradas, predominando os ácaros fitófagos, que representaram 98,4% dos ácaros coletados; o restante dos ácaros, incluídos em grupos designados como predominantemente predadores e de hábitos alimentares variados representaram 0,7 e 0,9% do total, respectivamente. A densidade média de A. guerreronis (110,0 ácaros por fruto) correspondeu a aproximadamente 1/10 dos níveis comumente relatados no nordeste do Brasil. Os ácaros predadores predominantes foram Proctolaelaps bulbosus Moraes, Reis & Gondim Jr. e Proctolaelaps bickleyi (Bram), nos frutos; Iphiseiodes zuluagai Denmark & Muma e Euseius citrifolius Denmark & Muma, nos folíolos; E. citrifolius, P. bickleyi e Typhlodromalus peregrinus (Muma), nas inflorescências; e P. bulbosus e P. bickleyi, nos frutos abortados; estes entretanto ocorreram sempre em baixos níveis populacionais (não mais que 2 ácaros por 100 frutos, 4 ácaros por 100 folíolos, 3 ácaros por 100 espiguetas de inflorescência e 5 ácaros por fruto abortado). Neoseiulus baraki (Athias-Henriot) e Neoseiulus paspalivorus (De Leon), dois dos principais predadores de A. guerreronis na região nordeste e em outros países, não foram encontrados. Os resultados não permitem concluir que os baixos níveis populacionais de A. guerreronis no Estado de São Paulo sejam devidos à ação de seus inimigos naturais, mas que sejam pelo menos em parte devidos às condições climáticas predominantes ao longo do ano na região em que o trabalho foi conduzido.
Aceria guerreronis Keifer is a pest of coconut in many countries. Colonies of this mite, also called the coconut mite, are mainly found underneath the bracts of young fruits, where they feed on meristematic tissues, often causing premature fruit drop. The aim of this study was to estimate the level of occurrence of A. guerreronis and other mites associated with it, to evaluate the possible role of predatory mites in controlling this mite. Samples were collected in July and December 2009 and April 2010 from 2 plantations of each of the following municipalities of São Paulo State: Cedral, Mirandópolis, Riolândia and Tupã (northwest), and Peruíbe (coast side). In each field, each sample consisted of 10 young fruits, 30 leaves and 5 spikelets of inflorescences, taken from each of 5 plants; in addition, up to 10 aborted fruits were also collected from each field, when present. Mites were found in all plant structures sampled; predominant mites were phytophagous, which accounted for 98.4% of the species collected; the remaining mites, included in the groups designated as \"predominantly predatory\" and \"of varied feeding habit\" accounted for 0.7 and 0.9% of the total, respectively. The average density of A. guerreronis (110,0 mites per fruit) accounted for approximately one tenth of the levels commonly reported in northeast Brazil. The main predators were Proctolaelaps bulbosus Moraes, Reis & Gondim Jr. and Proctolaelaps bickleyi (Bram), on fruits; Iphiseiodes zuluagai Denmark & Muma e Euseius citrifolius Denmark & Muma, on leaflets; E. citrifolius, P. bickleyi and Typhlodromalus peregrinus (Muma), on the inflorescences; and P. bulbosus and P. bickleyi on aborted fruits; these however were always found at low levels (not more than 2 per 100 fruits, 4 per 100 leaflets, 3 per 100 spikelets and 5 per 10 aborted fruit). Neoseiulus baraki (Athias-Henriot) and Neoseiulus paspalivorus (De Leon), two major predators of A. guerreronis in the northeast and in other countries, were not found. The results do not suggest that the low levels of A. guerreronis in São Paulo are due to the action of natural enemies, but they are at least partly due to climatic conditions prevailing during the year in the region where the study was conducted.

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Webber, J. D. "Phenology of hazelnut big bud mites in Canterbury and implications for management." Lincoln University, 2007. http://hdl.handle.net/10182/342.

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Eriophyoid big bud mites are key pests of hazelnuts throughout the world, although little is known of the identity and impact of the species on New Zealand hazelnut crops. The key objectives of this study were to determine the species of mite present on New Zealand crops, explore a method of monitoring mite emergence from overwintering big buds, determine the phenology of mites in relation to tree phenology and weather, and identify the optimum timing for control measures. The presence of both Phytoptus avellanae (Nalepa 1889) (Acari: Phytoptidae) and Cecidophyopsis vermiformis (Nalepa 1889) (Acari: Eriophyidae) was confirmed, the latter species being a new record for New Zealand. Preliminary diagnostic DNA sequences were determined for both species. A sticky band technique was developed to monitor mite emergence from overwintering big buds, and mite emergence was found to occur between early and late spring. Mite emergence and movement occurred when daily temperatures were greater than 15 degrees C and when mean temperatures were greater than 9 degrees C, with mite emergence increasing with temperature. It proved difficult to relate the phenology of hazelnut to mite emergence, however, the development of new buds during mite emergence was a crucial factor in the infestation of new buds. An accumulated heat sum model (DD), started at Julian date 152 and using a lower threshold temperature of 6 degrees C, predicted the onset of emergence on two cultivars and at two sites as occurring at approximately 172 DD. A regression model based on leaf number, bud height, bud width, DD and Julian date provided a more satisfactory prediction of percent accumulated mite emergence. It is recommended both peak mite emergence and the appearance of hazelnut buds should be used to optimise the time to apply control measures. Therefore, a control should be applied before buds measure 0.5 x 0.5 mm (width x height), are enclosed within the axil, and have a rounded tip, or, when 50% accumulated mite emergence has occurred, which ever occurs first. A preliminary field experiment tested the application of sulphur (40 g/10 litres of 800 g/kg No Fungus Super Sulphur) at 2, 50 and 80% accumulated mite emergence. The greatest reduction in mite numbers was achieved with an application at approximately 50% emergence. Considerable variation in mite emergence occurred between years, therefore optimum timing of controls would need to be determined by monitoring mites, new buds and weather conditions each year. Field collection of mites also identified the presence of Typhlodromus doreenae Schicha (Acari: Phytoseiidae) which would warrant further study for inclusion in an integrated mite control programme.

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Merfield, C. N. "Predator interactions within a trophic level : Phalangium opilio L. (Arachnida: Opiliones) and mites (Arachnida: Acari)." Diss., Lincoln University, 2000. http://hdl.handle.net/10182/21.

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This study investigated commensal feeding interactions between the European harvestman (P. opilio L.) and the predatory mites Balaustium spp. and Anystis baccarum L. It also investigated the feeding behaviour of P. opilio. Experiments were conducted in the laboratory using standardised temperature, humidity, photoperiod and experimental arenas, with eggs of the brown blowfly (Calliphora stygia F.) as prey facsimiles. Due to initial difficulties in obtaining enough predatory mites, mite feeding was manually simulated piercing blowfly eggs with a minuten pin. P. opilio consumed significantly more freeze-killed than live blowfly eggs, indicating that freezing induced chemical and/or physical changes to blowfly eggs that are detected by P. opilio. Significantly more manually pierced eggs were consumed by P. opilio compared with unpierced ones, demonstrating that piercing caused a chemical and/or physical to the egg and increased the feeding rates of P. opilio. Different densities of eggs had no effect on the numbers eaten by P. opilio and placing single pierced eggs next to groups of unpierced eggs also had no effect on the numbers of unpierced eggs eaten. These results suggest that P. opilio does not exhibit klinokinesis or orthokinesis to intensify its search for prey around the area where previous prey were located. P. opilio ate significantly more brown blowfly eggs that had previously been fed on by mites, demonstrating that a short term commensal interaction existed. However, further work is required to demonstrate if the relationship is commensal in the longer term. A comparison between hand-pierced and mite-pierced eggs showed that P. opilio ate significantly more of the former indicating that mite and hand piercing were quantitatively different. The potential for, and importance of, other commensal or mutual relationships between predators in agroecosystems is discussed. The lack of klinokinesis and orthokinesis in P. opilio is compared with other predators and parasitoids that do exhibit these behaviours. The means by which prey are detected by P. opilio are discussed in relation to interpreting behaviours such as prey inspection. Concerns about the effect of pre-treatment and handling of sentinel prey and the problems of using prey facsimiles are raised.

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Frost, William E. "The ecology of cereal rust mite Abacarus hystrix (Nalepa) in irrigated perennial dairy pastures in South Australia /." Title page, contents and summary only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phf9398.pdf.

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Ferreira, Paulo de Tarso de Oliveira. "Caracterização de um vírus baciliforme isolado de Solanum violaefolium transmitido pelo ácaro Brevipalpus phoenicis Geijskes (Acari: Tenuipalpidae)." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-09082005-130547/.

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Solano-violeta (Solanum violaefolium) é uma ornamental rasteira usada pra cobrir solos de áreas sombreadas. Um vírus que induz manchas anelares nas folhas, tentativamente designado de mancha anular do S. violaefoliumm (S. violaefolium ringspot vírus - SvRSV), transmitido pelo ácaro Brevipalpus phoenicis foi encontrado nesta planta em jardins de Piracicaba, SP. Trata-se de um vírus baciliforme que se acumula no lúmen do retículo endoplasmático induzindo viroplasma citoplasmático, assemelhando-se a outros vírus do tipo citoplasmático, dos transmitidos por ácaros Brevipalpus (Acari: Tenuipalpidea). Este trabalho relata algumas de suas propriedades biológicas e a caracterização molecular parcial. SvRSV foi ser transmitido mecanicamente e pelo B. phoenicis a várias outras espécies botânicas, sempre causando lesões localizadas. Destas, Datura stramonium mostrou-se a melhor como hospedeira experimental. As propriedades físicas do SvRSV in vitro foram: temperatura de inativação - 40-45 ºC; ponto final de diluição - 10-3-10-4; longevidade in vitro- 12 dias. Posteriormente, observou-se também infestação destas plantas por B. obovatus que em ensaios preliminares transmitiu o SvRSV. Em secções ultrafinas, as partículas do SvRSV mostraram-se ligeiramente mais delgadas que as de outros vírus do tipo citoplasmático, transmitidos por Brevipalpus, e por outro lado formavam eventualmente partículas mais longas, às vezes de ca. 1 µm. Como os demais vírus, do tipo citoplasmático, transmitido por Brevipalpus, induz a formação de um viroplasma denso e vacuolado no citoplasma. Em casos favoráveis foram observadas fases do processo de morfogênese por brotação a partir do material do viroplasma. Dada sua labilidade não foi possível conseguir sua purificação apesar das inúmeras tentativas, usando diferentes protocolos. Logrou-se a extração de dsRNA a partir de D. stramonium e a partir dele, obter-se dois fragmentos do genoma viral, identificados como parte da proteína de movimento e da replicase, após seu sequenciamento. Foram produzidos pares de primer baseado nestas seqüências que amplificaram especificamente, por RT-PCR, fragmentos de DNA de tamanho esperado, a partir do RNA total extraído de lesões foliares de S. violaefolium e D. stramonium infetados. Sondas baseadas nas seqüências obtidas hibridizaram com ss- e dsRNA de lesões de D. stramonium. Ensaios preliminares de RT-PCR e hibridização não resultaram em reação com alguns outros vírus transmitidos por Brevipalpus, do tipo citoplasmático, inclusive o da leprose dos citros (CiLV-C).
Solanum violaefolium is an ornamental Solanaceae, with prostrate, trailing growth cultivated in shaded areas. Plants exhibiting necrotic ringlike spots on the leaves have been found in several gardens and parks at Piracicaba SP. The ringspot symptoms on the leaves is caused by a vírus, named S. violaefolium ringspot virus (SvRSV), and is transmisible by mite Brevipalpus phoenicis (Acari: Tenuipalpidae). Short bacilliform particles are present within the cisternae of endoplasmic reticulum (ER) and often electron dense viroplasm is present in the cytoplasm, characterist of the cytoplasmatic type of Brevipalpus-borne virus. The present study reports some of its biological properties and partial molecular caracterization. SvRSV is easily transmitted to many plant species either by viruliferous B. phoenicis or mechanically, always causing local lesions. Datura stramonium was proved to be better as experimental host. Its physical properties in vitro were: inactivation thermal point 40-45 ºC; final diluition point - 10-3-10-4; longevity in vitro 12 days. Afterwards, its was observed that S. violaefolium plants were infested by B. obovatus that transmitted SvRSV in preliminary assays. Thin sections revealed that SvRSV particles are slightly thinner and sometimes appear very long. In some favorable sections intermediate steps of viral particle morphogenesis by a budding process of the dense material of the viroplasm toward the lumen of ER could be seen. Due to the fragility of the particles, several attempts to purify the virus have failed, despite many protocols tried. It was possible, however, to extract dsRNA from infected tissue of D. stramonium, and two segments of viral genome, respectively with homology to movement protein (mp) and replicase (rep) of some known viruses were obtained. Primers were designed based in these sequences, which amplified by RT-PCR, fragments of DNA of expected size from total RNA extracts from leaves lesions of infected S. violaefolium and D. stramonium. Probes based on obtained sequences hibridizated with ss- and dsRNA from lesions of S. violaefolium and D. stramonium. Preliminary assays of RT-PCR and hybridization did not result in positive reaction with other cytoplasmatic type of Brevipalpus-borne viruses, including citrus leprosis (CiLVC).

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Amaral, Ingrid. "Biologia e tabela de vida de Brevipalpus yothersi (Acari: Tenuipalpidae) oriundos de diferentes regiões citrícolas do Estado de São Paulo /." Jaboticabal, 2016. http://hdl.handle.net/11449/137926.

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Orientador: Daniel Junior de Andrade
Banca: Marineide Rosa Vieira
Banca: Renato Beozzo Bassanezi
Resumo: O ácaro Brevipalpus yothersi Baker é vetor da leprose dos citros, principal doença viral da citricultura mundial. Informações sobre a biologia de B. yothersi são essenciais para compreender a dinâmica populacional do ácaro no campo e inferir se mudanças no manejo do pomar em função da região pode alterar a biologia do ácaro. O objetivo do trabalho foi determinar a biologia e elaborar a tabela de vida de fertilidade de B. yothersi coletados em diferentes regiões citrícolas do estado de São Paulo. Os experimentos foram realizados no Laboratório de Acarologia, pertencente à Faculdade de Ciências Agrárias e Veterinárias - FCAV/UNESP, Jaboticabal - SP. Os ácaros foram coletados em pomares cítricos das regiões de Barretos, Jales e Santa Cruz do Rio Pardo, posteriormente, em laboratório, foram multiplicados em frutos de laranja. Os parâmetros biológicos avaliados foram duração das fases de desenvolvimento, oviposição, período de incubação, viabilidade dos ovos, longevidade, taxa líquida de reprodução (Ro), tempo médio de geração (T), taxa intrínseca de crescimento populacional (rm) e taxa finita de crescimento populacional (λ). Estes parâmetros foram avaliados em dois experimentos, o primeiro consistiu na biologia de B. yothersi em frutos isentos de resíduos de produtos fitossanitários à 23±1ºC e o segundo sob frutos com resíduo de espirodiclofeno à 25±1ºC. As observações foram realizadas diariamente, pela manhã e ao fim da tarde. A duração do desenvolvimento, longevidade, período d... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The mite Brevipalpus yothersi Baker is the vector of the citrus leprosis, major viral disease of citrus worldwide. Information about B. yothersi's biology are essential to understanding the population dynamics of the mite in the field and infer whether changes in orchard management by region can change the mite biology. The objective was to determine the biology and prepare the fertility life table of B. yothersi collected in different citrus regions of São Paulo state. The experiments were performed in Acarology Laboratory, belonging to the Faculty of Agricultural and Veterinary Sciences - FCAV/UNESP, Jaboticabal - SP. The mites were collected in citrus orchards in the regions of Barretos, Jales and Santa Cruz do Rio Pardo, later in the laboratory were multiplied in orange fruits. The biological parameters assessed were duration of the stages of development, oviposition, incubation period, egg viability, longevity, net reproductive rate (Ro), mean generation time (T), intrinsic rate of increase (rm) and finite rate increase (λ). These parameters were evaluated in two experiments, the first consisted the biology of B. yothersi in fruits free of residues of pesticides at 23 ± 1°C and the second consisting of the biology of B. yothersi under fruit with spirodiclofen residue at 25 ± 1°C . The observations were performed daily, in the morning and in the afternoon. The duration of the development, longevity, pre-oviposition period, oviposition rate and number of B. yothersi eggs s... (Complete abstract click electronic access below)
Mestre

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Melville, Cirano Cruz [UNESP]. "Distribuição espacial e determinação da depreciação quantitativa e qualitativa causada por Tetranychus ogmophallos (Acari: Tetranychidae) ao amendoinzeiro." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/123666.

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Nas últimas safras, constatou-se aumento significativo na incidência de ácaros-praga nos campos de produção de amendoim. Altas infestações de ácaros comprometem o desenvolvimento e a produtividade da cultura, elevam os custos de produção e ainda podem contribuir para aumento do impacto negativo sobre o meio ambiente. Sabe-se que os principais ácaros-praga que vêm causando prejuízos aos produtores em São Paulo pertencem à família Tetranychidae. Portanto, os objetivos do trabalho foram estudar a distribuição espacial do ácaro Tetranychus ogmophallos Ferreira e Flechtmann (Acari: Tetranychidae) e determinar a depreciação quantitativa e qualitativa causada por esse ácaro à cultura do amendoim. Os experimentos foram realizados a campo e em casa de vegetação. Para realização dos experimentos a campo foram selecionadas duas áreas de amendoim, sendo uma área localizada na Faculdade de Ciências Agrárias e Veterinárias - UNESP/FCAV e outra na zona rural do município de Jaboticabal-SP, Brasil. Nas áreas selecionadas, foram vistoriados materiais vegetais compostos por folhas, folíolos e pecíolos, coletados na parte inferior e superior de plantas distanciadas de 22,5 metros uma das outras. A primeira coleta foi realizada 28 dias após o plantio, e as demais a cada quinze dias. Em contrapartida, foram realizados em casa de vegetação da UNESP/FCAV quatro experimentos para determinar a depreciação quantitativa e qualitativa causada pelo ácaro T. ogmophallos ao amendoinzeiro. Estes experimentos foram instalados em delineamento inteiramente casualizado, compostos por dois tratamentos com vinte repetições cada. Os tratamentos empregados foram plantas infestadas e não infestadas pelo ácaro. Em cada experimento variou-se a época de infestação com o ácaro (15, 30, 60 e 90 dias após a emergência das plântulas). Em cada infestação transferiram-se aproximadamente 3.000 ácaros. Os dados foram submetidos à ...
In recent growing seasons, there was a significant increase in the incidence of mite in peanut fields. Large infestations of pest mites affect the development and crop productivity, increases production costs, and contribute to increased environmental contamination due to intensive use of pesticides to control these arthropod. Field Information and observations indicate that the main pest mites that have caused damage to producers in São Paulo belong to Tetranychidae. This work aimed to study the type of spatial distribution of Tetranychus ogmophallos Ferreira e Flechtmann (Acari: Tetranychidae) mite on peanut, which probability distribution model that best represents your behavior in the field, as well as, determine the quantitative and qualitative depreciation caused by the mite to peanut crop. The experiments were carried out in the field and in a greenhouse belonging to the Faculty of Agricultural and Veterinary Sciences - UNESP/FCAV, Jaboticabal - SP. To determine the spatial distribution of the mite on peanut two fields with peanut were selected. In selected fields were examined plant materials consisting of leaves, leaflets and petioles, collected in the lower and top of the plant. The plants were spaced 22.5 m from one another. The first collect of samples of plant material was performed twenties days after planting, and the other every fifteen days. To determine the quantitative and qualitative depreciation experiments were conducted in a greenhouse, arranged in a completely randomized design consisting of two treatments, plants infested and non-infested (control), with 20 repetitions. The age of infestation varied in each experiment based on the number of days (15, 30, 60, and 90) after seedling emergence. Approximately 3,000 mites were transferred for each infestation. Data were submitted to analysis of variance, and means were compared by F test at 5% probability and the aggregation indexes were used to study the ...

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Melville, Cirano Cruz. "Distribuição espacial e determinação da depreciação quantitativa e qualitativa causada por Tetranychus ogmophallos (Acari: Tetranychidae) ao amendoinzeiro /." Jaboticabal, 2015. http://hdl.handle.net/11449/123666.

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Orientador: Daniel Junior de Andrade
Banca: Odair Aparecido Fernandes
Banca: Marcos Doniseti Michelotto
Resumo: Nas últimas safras, constatou-se aumento significativo na incidência de ácaros-praga nos campos de produção de amendoim. Altas infestações de ácaros comprometem o desenvolvimento e a produtividade da cultura, elevam os custos de produção e ainda podem contribuir para aumento do impacto negativo sobre o meio ambiente. Sabe-se que os principais ácaros-praga que vêm causando prejuízos aos produtores em São Paulo pertencem à família Tetranychidae. Portanto, os objetivos do trabalho foram estudar a distribuição espacial do ácaro Tetranychus ogmophallos Ferreira e Flechtmann (Acari: Tetranychidae) e determinar a depreciação quantitativa e qualitativa causada por esse ácaro à cultura do amendoim. Os experimentos foram realizados a campo e em casa de vegetação. Para realização dos experimentos a campo foram selecionadas duas áreas de amendoim, sendo uma área localizada na Faculdade de Ciências Agrárias e Veterinárias - UNESP/FCAV e outra na zona rural do município de Jaboticabal-SP, Brasil. Nas áreas selecionadas, foram vistoriados materiais vegetais compostos por folhas, folíolos e pecíolos, coletados na parte inferior e superior de plantas distanciadas de 22,5 metros uma das outras. A primeira coleta foi realizada 28 dias após o plantio, e as demais a cada quinze dias. Em contrapartida, foram realizados em casa de vegetação da UNESP/FCAV quatro experimentos para determinar a depreciação quantitativa e qualitativa causada pelo ácaro T. ogmophallos ao amendoinzeiro. Estes experimentos foram instalados em delineamento inteiramente casualizado, compostos por dois tratamentos com vinte repetições cada. Os tratamentos empregados foram plantas infestadas e não infestadas pelo ácaro. Em cada experimento variou-se a época de infestação com o ácaro (15, 30, 60 e 90 dias após a emergência das plântulas). Em cada infestação transferiram-se aproximadamente 3.000 ácaros. Os dados foram submetidos à ...
Abstract: In recent growing seasons, there was a significant increase in the incidence of mite in peanut fields. Large infestations of pest mites affect the development and crop productivity, increases production costs, and contribute to increased environmental contamination due to intensive use of pesticides to control these arthropod. Field Information and observations indicate that the main pest mites that have caused damage to producers in São Paulo belong to Tetranychidae. This work aimed to study the type of spatial distribution of Tetranychus ogmophallos Ferreira e Flechtmann (Acari: Tetranychidae) mite on peanut, which probability distribution model that best represents your behavior in the field, as well as, determine the quantitative and qualitative depreciation caused by the mite to peanut crop. The experiments were carried out in the field and in a greenhouse belonging to the Faculty of Agricultural and Veterinary Sciences - UNESP/FCAV, Jaboticabal - SP. To determine the spatial distribution of the mite on peanut two fields with peanut were selected. In selected fields were examined plant materials consisting of leaves, leaflets and petioles, collected in the lower and top of the plant. The plants were spaced 22.5 m from one another. The first collect of samples of plant material was performed twenties days after planting, and the other every fifteen days. To determine the quantitative and qualitative depreciation experiments were conducted in a greenhouse, arranged in a completely randomized design consisting of two treatments, plants infested and non-infested (control), with 20 repetitions. The age of infestation varied in each experiment based on the number of days (15, 30, 60, and 90) after seedling emergence. Approximately 3,000 mites were transferred for each infestation. Data were submitted to analysis of variance, and means were compared by F test at 5% probability and the aggregation indexes were used to study the ...
Mestre

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Salazar, Laura Cristina Garita. "Relação vírus-vetor-hospedeira no patossistema da leprose dos citros." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-18042013-165710/.

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A leprose dos citros é considerada uma das doenças mais destrutivas da indústria citrícola. O patossistema dessa doença envolve o agente causal o Citrus leprosis virus C, o vetor Brevipalpus phoenicis Geijskes (Acari: Tenuipalpidae) e as plantas hospedeiras. Este vírus com genoma conhecido é membro tipo do gênero Cilevirus. Causa sintomas localizados nas folhas, frutos e caules e está restrito ao continente Americano. Apesar de muitos esforços para se conhecer o patossistema, ainda existem muitas questões pendentes sobre as interações. O presente trabalho teve como objetivo obter informações detalhadas sobre as relações vetorvírus- hospedeiro da leprose citoplasmática, estando dividido em três objetivos: 1. Procurou-se uma planta indicadora padrão que fosse de facil obtenção, manejo e baixo custo, e que expressase em curto tempo os sintomas de CiLV-C e outros vírus transmitidos por Brevipalpus (VTBr); 2. Determinar parâmetros como o período de acesso para aquisição e inoculação do CiLV-C pelo ácaro vetor, o período de retenção do vírus pelo ácaro, avaliação da capacidade das diferentes fases do ácaro de transmitir o vírus e a % de indivíduos de uma população de ácaros colonizando plantas afetadas pela leprose capazes de transmitir o vírus; 3. Avaliar um grande número de espécies de plantas, de diferentes famílias botânicas, quanto à suscetibilidade experimental à infecção pelo CiLV-C, pelo ácaro vetor. A presença de CiLV-C nestes ensaios foi confirmada por testes de ELISA, RT-PCR, microscopia eletrônica de transmissão e imunofluorescência. O feijoeiro comum (Phaseolus vulgaris L.) reage com lesões necróticas locais em apenas cinco dias à inoculação com ácaros virulíferos, podendo-se reduzir para dois dias se as plantas forem incubadas a 28ºC. O cv. ,,Una\" foi selecionado como planta-teste padrão dentre 113 cvs. avaliados. Outros vírus transmitidos por Brevipalpus do tipo citoplasmático (VTBr) como vírus da pinta verde do maracujá (Passion fruit green spot virus PFGSV), vírus da mancha anular de Ligustrum (Ligustrum ringspot virus LigRSV) e mancha verde do hibisco (Hibiscus green spot vírus HGSV) também causaram lesões locais necróticas em feijoeiro. Usando feijão como planta teste e ácaros virulíferos, se determinou o período de acesso à aquisição do vírus-4 h; período de acesso à inoculação do vírus-4h; período de retenção do vírus no ácaro de 12 dias, porcentagem de ácaros virulíferos, colonizando tecidos infectados, transmitirem CiLV-C em até 45%. Os experimentos também confirmaram que todas as etapas de desenvolvimento do ácaro (larvas, proto-deutoninfa e adultos) são capazes de transmitir CiLV-C, inclusive confirmou-se que o macho tem a capacidade de transmissão e que o vírus pode ser adquirido a partir de lesões de folhas, frutos e caules. Não se constatou transmissão transovariana do CiLV-C. Foram testadas 140 espécies, de 45 famílias, dentro das quais 62 espécies de 26 famílias apresentaram lesões localizadas nas folhas. Destas, 46 espécies sintomáticas, o CiLV-C foi detectado em pelo menos um dos testes para sua detecção, confirmando a transmissão. O conhecimento de parâmetros de alimentação, retenção do vírus e porcentagem de ácaros viruliferos na população, além do genoma de hospedeiras suscetíveis ao vírus tem importantes implicações no entendimento da epidemiologia, na quarentena e podem oferecer indícios da origem do CiLV-C.
Citrus leprosis (CL), caused by the Citrus leprosis virus C (CiLV-C), is reported only in the American continent. The pathosystem of the CL involves the causal agent, the main vector Brevipalpus phoenicis Geijeskes (Acari: Tenuipalpidae) and the susceptible hosts. For long time only Citrus spp. were considered the sole susceptible host. The entire genome of the CiLV-C was sequenced and a new genus, Cilevirus, was assigned for this virus. CL is characterized by the induction of localized symptoms on the leaves, fruits and stems. Important advances were made recently for the understanding of CL pathosystem, but despite these efforts little is known about details of the virus/vector/host relationship. The present work aimed to cover such deficiencies. In the first place a search of suitable indicator plant was made and the common bean (Phaseolus vulgaris L.) was found to respond with localized necrotic lesions after infestation with viruliferous B. phoenicis in five days and when infested leaves are incubated at 28°C. Furthermore, bean plants are easy and cheap to produce and handle. The black bean cv. ,,IAC Una\" was adopted as a standard test variety, among 113 assayed cultivars of various genetic backgrounds. Common bean plants mite-inoculated with other cytoplasmic-type Brevipalpus-transmitted viruses (BrTVs) [Passion fruit green spot virus (PFGSV), Solanum violaefolium ringspot virus (SvRSV), Ligustrum ringspot virus (LigRSV) and Hibiscus green spot virus (HGSV)] also responded with necrotic local lesions and could serve as test plants for these viruses. Detecion of these viruses were made by RTPCR and/or transmission electron microscopy. Using common bean as test plant, some parameters of the vector/virus relationship were determined: virus acquisition feeding period- 4 h; virus inoculation feeding period- 4h; period of retention of the virus by a single viruliferous mite- at least 12 days; percentage of viruliferous mites from a mites colonizing infected tissues- 45%. The experiments also confirmed that all the developmental stages of the mite (larvae, proto- and deutonymph, adult) as well as males are able to transmit CiLV-C. No transovarial passage of the CiLV-C was registered. The virus can be acquired from lesions of leaves, fruits and stems. To assess the experimental host range of CiLV-C, a large number of plant species were inoculated with B. phoenicis, viruliferous to CiLV-C, under experimental conditions. Of the140 species tested, belonging to 45 families, 62 (of 26 families) produced localized lesions on inoculated leaves. Of these 62 plants producing local lesions, 45 had the presence of CiLV-C confirmed by at least one of the assays to detect the virus (RT-PCR, ELISA, transmission electron microscopy and immunofluorescence). These assays were also used to confirm the presence of CiLV-C in transmission experiments. Although only few non Citrus species were found naturally infected by CiLV-C, present results show that a large number of plant species are susceptible to the virus with implications on the epidemiology, quarantine and the evolution of the citrus leprosis pathosystem.

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Ribeiro, Fabricio Rainha. "Identificação de bactérias endossimbiontes associadas aos ácaros Tetranychus evansi e Tetranychus urticae (Acari: Tetranychidae) e seus efeitos na manipulação do mecanismo de defesa do tomateiro Lycopersicon esculentum Mill." Universidade Federal de Viçosa, 2011. http://locus.ufv.br/handle/123456789/3931.

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The tomato is one of the most important vegetables produced in Brazil, playing an important role in the economy and creating jobs. In countries of South America, Europe and Africa, the mite Tetranychus evansi is considered an important pest of this crop. Recent studies have shown that this mite manipulates the defense of the plant reducing its defensive products. The objective of this study was to investigate whether endosymbiotic bacteria associated with the mite T. evansi play a role in manipulating the defenses of the tomato plant. The mite T. urticae was used as a standard, which is known to induce plant defense response. Bacterial DNA was extracted from T. evansi and T. urticae with subsequent denaturing gradient gel electrophoresis to compare bacterial diversity between these species, observing that T. evansi has a higher bacterial diversity than T. urticae. To determine if bacteria associated with T. evansi provide some advantage for its development and reproduction, as well as contributing to suppress the defenses of plants, mites were obtained without endosymbionts by treating them with a tetracycline solution. Mites treated with tetracycline showed no significant differences (p> 0.05) in development, oviposition and mortality. However, plants attacked by treated mites showed higher lipoxygenase activity and increased inhibition of trypsin (p <0.05) compared to clean plants and plants attacked by mites not treated with tetracycline. These results show that plants attacked by T. evansi without endosymbiotic bacteria activated their defense mechanism. Thus, these results suggest that bacteria may assist the mites in manipulating plant defense, making them more susceptible to attack.
A cultura do tomateiro é uma das mais importantes hortaliças produzidas no Brasil, apresentando destacada influência na economia e geração de empregos. Em países da América do Sul, Europa e África, o ácaro Tetranychus evansi é considerado uma importante praga dessa cultura. Recentes estudos demonstraram que este ácaro manipula a defesa da planta reduzindo seus produtos de defesa. O objetivo deste trabalho foi investigar se bactérias endossimbiontes associadas ao ácaro T. evansi tem função na manipulação de defesa de T.evansi no tomateiro. Para isso foi utilizado também o ácaro T. urticae como padrão, que é conhecido por induzir resposta de defesa de planta. Foi realizada a extração de DNA bacteriano de T. evansi e T. urticae com posterior corrida eletroforética em gel com gradiente desnaturante para comparar a diversidade bacteriana entre estas espécies, foi observado que T. evansi possui uma diversidade bacteriana superior ao T. urticae. Para avaliar se as bactérias associadas ao T. evansi proporcionam alguma vantagem ao seu desenvolvimento e reprodução, bem como na contribuição de suprimir as defesas das plantas, foram obtidos ácaros sem endossimbiontes através do tratamento destes, com solução de tetraciclina. Ácaros tratados com tetraciclina não apresentaram diferenças significativas (p > 0,05) no desenvolvimento, oviposição e mortalidade. Entretanto, as plantas atacadas por ácaros tratados apresentaram maior atividade de lipoxigenase e maior inibição de tripsina (p<0,05), comparado com plantas limpas e plantas atacadas por ácaros não tratados com tetraciclina. Estes resultados evidenciam que plantas atacadas por T. evansi sem endossimbiontes bacterianos ativaram seu mecanismo de defesa. Sendo assim, estes resultados sugerem que as bactérias podem auxiliar os ácaros na manipulação da defesa da planta, deixando-as mais susceptíveis ao ataque e à alimentação.

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Castro, Thiago Rodrigues de. "Estudos para o desenvolvimento de metodologia da produção in vivo do fungo Neozygites floridana Weiser e Muma para controle do ácaro Tetrancychus urticae Koch." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-18102011-165455/.

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Uma das principais espécies de ácaro praga é o ácaro rajado, Tetranychus urticae. Um dos inimigos naturais mais importantes deste ácaro é o patógeno Neozygites floridana. Para viabilizar o uso deste patógeno através de liberações inoculativas, ainda são necessárias informações básicas para subsidiar o desenvolvimento de uma metodologia de produção em escala e para liberações do fungo em campo. Para tanto, foi determinado em laboratório, a exigência de umidade e temperatura para a esporulação do fungo, colocando-se ácaros mumificados em folhas de feijão-de-porco. A 80 e 85% de umidade, em nenhuma das temperaturas (13, 17, 21 e 25°C) ocorreu esporulação. O fungo esporulou pouco a 90% UR em todas as temperaturas. As melhores condições para formação de capiloconídios foram a 95% e 100% UR a 21°C e 25°C. Ácaros mumificados foram colocados para esporular em feijão-de-porco em telados em diferentes épocas do ano e a temperatura e umidade monitorada. Notou-se que acima de 13°C o fungo conseguiu produzir um número considerável de conídios primários (>130) mesmo a 90% UR. Entretanto, nesta UR somente a 25°C a produção de capiloconídios foi significativa (>389). Determinou-se o efeito da exposição de duas intensidades luminosas (2.960 Lux e 15.392 Lux), três fotoperíodos (24h de luz, 12:12h(L:E) e 24h de escuro) e duas temperaturas (18°C e 23°C), na produção de conídios primários e de capiloconídios de isolados da Noruega e do Brasil. Ácaros mumificados foram expostos aos diferentes tratamentos em BOD. Não foram encontradas diferenças entre os dois isolados nas duas temperaturas testadas. Os resultados para o fotoperíodo de 12:12h(L:E) foram similares aos encontrados para 24h de escuro. A inibição da luz na formação de capiloconídios foi maior no isolado Norueguês. Baixa intensidade de luz por 24h teve efeito moderado na esporulação dos dois isolados, mas inibiu fortemente a formação de capiloconídios no isolado Norueguês. Foram realizados estudos para avaliar o efeito de agrotóxicos utilizados na produção de morango no Brasil e na Noruega sobre a esporulação e produção de capiloconídios de N. floridana em laboratório. Os resultados revelaram que Tebuconazol, Fenpropatrina na concentração recomendada e Abamectina na metade da concentração recomendada, foram os menos agressivos a N. floridana. Foram também realizadas tentativas de produção em escala deste fungo. Através de inoculações experimentais em telado foi possível induzir epizootias em populações de T. urticae em plantas de feijão de porco em vasos nos telados. Liberações de quatro ácaros mumificados por vaso foi a forma mais prática de inoculação. Maiores quantidades de ácaros mumificados foram produzidos quando as condições climáticas foram caracterizadas por alta UR e 20°C, sendo que durante o inverno a produção não foi eficiente. O uso de lâmpadas e ventiladores durante o período noturno ao final da epizootia, foi eficiente em inibir a esporulação e garantir a qualidade dos ácaros mumificados para o armazenamento. Embora tenha sido possível produzir um grande número de ácaros mumificados, vários estudos ainda são necessários para desenvolver uma metodologia de produção em escala para que seja economicamente viável a sua utilização em campo.
One of the main pest mite species is the Twospotted Spider Mite, Tetranychus urticae. The most important natural enemy of this mite is the pathogen Neozygites floridana. To enabling the use of this pathogen through inoculative releases, basic information is still needed to support the large scale methodology development for fungus production and release in the field. It was determined in the laboratory, the humidity and temperature requirements for fungus sporulation, by placing mummified mites on Jack-bean leaves. There was no sporulation at any of the temperatures tested (13, 17, 21 and 25°C) at 80% and 85% RH. The fungus had low sporulation at 90% RH at all temperatures. The best conditions for the capilloconidia development were 95% and 100%RH at 21°C and 25°C. Mummified mites were placed to sporulate in Jack-bean plants inside screenhouses at different times of year and temperature and humidity were monitored. It was noted that above 13°C the fungus can produce a considerable number of primary conidia (> 130) even at 90%RH. However, only at 90%RH and 25°C the capilloconidia production is significant (> 389). It was determined the effect of exposure of two light intensities (2.960 Lux and 15.392 Lux), three photoperiods (24h of light, 12:12h(L:D) and 24h of darkness) and two temperatures (18°C and 23°C), on the production of primary conidia and capilloconidia of N. floridana isolates from Norway and Brazil. Fungus-killed cadavers by each of the isolates were exposed to different treatments in BOD. No differences were found between the two isolates in the two temperatures tested. The results for the 12:12h(L:D) were similar to those found for 24h of darkness. Light inhibition of capilloconidia formation was greater on Norwegian isolate. Low light intensity for 24h had a mild effect on sporulation of the two isolates, but strongly inhibited the formation of capilloconidia of the Norwegian isolate. Studies were carried out to evaluate the effect of pesticides used in production of strawberries in both countries on sporulation and capilloconidia production of N. floridana in the laboratory. The results showed that Tebuconazole and Fenpropatrin in the recommended concentration and Abamectin in half of the recommended concentration were the less aggressive to N. floridana. Attempts to scale production of this fungus were also made. Through experimental inoculations it was possible to induce epizootics of the fungus in T. urticae populations on Jack-beans, planted in pots in screenhouses. The most convenient way for inoculation of the fungus was to release four mummified mites per pot. Larger quantities of mummified mites by N. floridana were produced when climatic conditions were characterized by high RH and 20°C, during the winter production was inefficient. The use of light and fans at night during the end of the epizootic phase, was effective in inhibiting the sporulation of the fungus and ensure the quality of mummified mites for storage. Although it was possible to produce a large number of mummified mites, several studies are still needed to develop an economically viable methodology for large scale production for field use.

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Pereira, Juliana Aparecida. "Resposta de genótipos de citros à leprose e variabilidade genética da ORF p29 do vírus da leprose dos citros C (CiLV-C)." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11138/tde-31052012-082524/.

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Os vírus possuem potencial de variabilidade genética muito alto, isso porque necessitam divergir seu material genético suficientemente para se adaptar às inúmeras mudanças às quais são submetidos. Portanto, a variabilidade genética é essencial para a sobrevivência desses organismos; é o primeiro passo para a adaptação em um novo hospedeiro, quebra de resistência, alterações nos sintomas e virulência, o que justifica o interesse em estudos nessa área. Os estudos de variabilidade consistem numa excelente ferramenta para a compreensão da evolução dos vírus e busca pelo manejo adequado de doenças virais. Por isso objetivou-se estudar a variabilidade genética da ORF p29 do CiLV-C, a fim de gerar informações relevantes acerca do patossistema e da preponderância de isolados, com possíveis implicações na epidemiologia da doença e seu manejo no campo, além de uma melhor compreensão sobre a evolução desse vírus, que até então nunca havia sido explorada. Neste trabalho foram avaliadas plantas de citros e outras hospedeiras potenciais do CiLV-C. Os resultados sugerem que as plantas de tangerina Cravo, Tardia da Sicília, Cleópatra, Vermelha, tangor Ortanique, laranja Azeda e trapoeraba são suscetíveis à doença e também podem servir como fontes de inóculo do vírus para citros. Já as plantas de limão Siciliano e Cravo, e limas ácidas Tahiti e Galego e Mimosa caesalpiniaefolia mostraram-se resistentes à doença, mas não à colonização do ácaro vetor. As plantas de Malvaviscus arboreus e Solanum violaefolium não apresentaram sintomas, mas mostraram-se possíveis fontes de inóculo do vírus para plantas de citros. Além disso, foram avaliadas as respostas de 62 genótipos de tangerinas e seus híbridos à doença, sendo que 15 mostraram-se resistentes e podem, posteriormente, ser utilizados em programas de melhoramento genético, que é uma das alternativas para reduzir o uso de pesticidas para o controle do vetor. Foi identificada baixa variabilidade genética entre os isolados do CiLV-C, independentemente do hospedeiro ou localidade, entretanto, o isolado de São José do Rio Preto pareceu ser o mais divergente e capaz de passar suas alterações durante sua transmissão a outros hospedeiros. Mais estudos devem ser feitos para que conclusões inquestionáveis sejam tiradas desse assunto, mas os resultados obtidos abriram um novo leque de possibilidades para futuros estudos nessa área até então pouco explorada.
Viruses have, potentially, broad genetic variability because of their need to adapt to several changes that they are exposed to. Therefore, genetic variability is essential for their survival; it is the first step to adapt to a new host, to break resistance down, to change symptoms and virulence, which justifies the interest in studies in this area. These studies consist in a great tool for a better understanding on the virus evolution and the search for a proper management of viral diseases. Hence, it was aimed to study the genetic variability of ORF p29 from CiLV-C in order to generate relevant information about the pathosystem and the predominance of isolates with possible implications on the epidemiology of the disease and its management in the field, besides a better understanding on the evolution of this virus, which has never been explored before. In this work, we evaluated citrus plants and potential hosts for CiLV-C. The results suggest that the plants of Cravo, Tardia da Sicília, Cleopatra, and Vermelha mandarin, Ortanique tangor, Sour orange and spiderwort are susceptible to the disease and can also serve as sources of inoculum of the virus to citrus. Siciliano lemon, Rangpur, Tahiti, and Mexican limes, and Mimosa caesalpiniaefolia were resistant to the disease, but not to the colonization of the mite vector. Malvaviscus arboreus and Solanum violaefolium plants did not present symptoms, but can be considered possible sources of CiLV-C inoculum to citrus plants. In addition, we evaluated the response of 62 mandarin genotypes and their hybrids to the disease. Fifteen of them were considered resistant and could be used in breeding programs with the objective to reduce the use of pesticides to control the vector. Low genetic variability was found amongst CiLV-C isolates, regardless of the host or geographic region; however, the São José do Rio Preto isolate was the most divergent and the changes in nucleotides were transmitted to the other hosts. Further studies should be conducted before unquestionable conclusions can be drawn from this issue, but the results obtained here have opened a new range of possibilities for future studies in this area so far almost unexplored.

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Calegario, Renata Faier. "Detecção do vírus da leprose dos citros nos tecidos da planta infectada e do ácaro vetor Brevipalpus phoenicis Geijskes (Acari: Tenuipalpidae)." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-24062009-082631/.

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A leprose é uma das principais doenças na citricultura brasileira devido à sua ocorrência difundida nos pomares e aos altos custos para o controle químico do ácaro vetor. A doença compromete a produção da planta e sua vida útil, manifestando-se através de lesões locais cloróticas ou necróticas em folhas, ramos e frutos, levando à queda prematura destes órgãos e à seca de ramos. O patógeno, Citrus leprosis virus C (CiLV-C), recentemente classificado como espécie tipo de um novo gênero de vírus de planta, Cilevirus, é transmitido pelo ácaro Brevipalpus phoenicis (Geijskes). Apesar de haver consenso de que a doença tem etiologia viral, ainda existem muitas questões pendentes sobre as interações vírus-planta-vetor, cujas soluções contribuirão para o controle integrado da doença. O presente trabalho teve como objetivo obter informações sobre a interação do vírus com células hospedeiras através de ensaios de imunolocalização das proteínas MP (putativa proteína de movimento), helicase (associada à replicação) e p29 (putativa proteína capsidial) do CiLV-C. Para tal, as sequências codificadoras das ORFs mp e hel foram amplificadas via RT-PCR e clonadas em vetor de expressão. Em seguida, promoveu-se a expressão in vitro das respectivas proteínas em células de E. coli e purificação por cromatografia de afinidade e troca iônica. A proteína MP pura foi utilizada para produção de antissoro policlonal específico que foi testado quanto à especificidade por métodos sorológicos. Os resultados do ELISA mostraram que o antissoro apresentou reação positiva com extratos foliares de lesões lepróticas em todos os estágios de desenvolvimento da doença, quando utilizado em altas concentrações. Além disso, lesões maduras reagiram mais intensamente que lesões mais novas. Por Western Blot, detectou-se somente a proteína pura, não sendo possível obter reação positiva em extrato de lesões foliares. Também não foi possível detectar a MP por imunolocalização in situ. Os resultados em conjunto sugerem que ocorre baixo nível de expressão da MP nos tecidos do hospedeiro. Empregando-se anticorpo policlonal contra proteína p29 do CiLV-C, foi possível detectar o CiLV-C em extratos de lesões foliares de leprose por ambos os métodos sorológicos testados e também por Tissue Blotting. Ensaios de imunolocalização in situ permitiram confirmar que as partículas baciliformes presentes em cisternas do retículo endoplasmático de tecidos de lesões lepróticas em plantas representam de fato vírions do CiLV-C. Além disso, também demonstrou-se que o viroplasma que ocorre no citoplasma representa o sítio de acúmulo da proteína p29. Este mesmo ensaio revelou que partículas baciliformes que ocorrem entre membranas de células adjacentes (intestino médio, glândulas prosomais, músculos e epiderme) de B. phoenicis virulíferos são de fato do CiLV-C. A ausência de viroplasma no ácaro sugere que a relação vírus/vetor seria do tipo circulativo, sem replicação. Baseado neste fato discutem-se alternativas para explicar como o vírus trafegaria do lúmen do intestino até o duto salivar para causar infecção numa planta sadia.
Citrus leprosis is one of the most important diseases in the Brazilian citrus production due to the wide occurrence in orchards and also to the high costs involved in the chemical control of the mite vector. The disease affects the plant production and longevity and it is characterized by localized chlorotic and/or necrotic spots on the leaves, stems and fruits. Affected leaves and fruits may drop prematurely and dieback can be observed in stems. The pathogen, Citrus leprosis virus C (CiLV-C), recently considered as the type member of a new genus, Cilevirus, is transmitted by the mite Brevipalpus phoenicis Geijskes. Despite the consensus that citrus leprosis has viral etiology, there are many pending questions regarding the viral interactions with the infected plant and the viruliferous mites. The solution of these questions may contribute to a better disease integrated management. This work aimed to obtain a better understanding about the virus-plant-vector relationship with the host cell by immunolocalization assays of the putative movement protein (MP), helicase (protein involved in the viral replication) and p29 (putative coat protein) of the CiLV-C. ORFs coding sequences of mp and hel was amplified by RT-PCR and cloned in the expression vector. Afterwards, in vitro expression of these proteins in E. coli and its purification by affinity chromatography were realized. The purified MP was used to produce specific polyclonal antibody that was tested for specificity by serological methods. The ELISA results showed that high concentration antibody reacted with the leaves extracts from lesions in all the disease stage of development. Furthermore, the old lesions reacted more intensely than the younger. Western blot (which detected only the pure protein) and in situ immunolocalization assays failed to detect the native MP in lesioned leave extracts. The results as a hole suggest the occurrence of low expression of MP in host tissue. The polyclonal antibody against p29 was able to detect the virus in lesioned plant extracts by PTA-ELISA, Western Blot, and Tissue Blotting. The viral nature of the putative viral particles, present within endoplasmic reticulum cisternae of infected leaf tissue, was confirmed by immunogold label. The labeling also occurred intensely in the viroplasmas, indicating that these structures represent p29 protein accumulation site. Putative virus particles, visualized in viruliferous B. phoenicis, between membranes of adjacent cells (midgut, prosomal glands, epidermis, muscles), was also immunogold labeled indicating that they represent CiLV-C. The absence of viroplasma in the mite tissues suggests that CiLV-C / B. phoenicis relationship is of the circulative type, without replication. Based on this finding, we search for possible alternatives for the viral circulation in the mite body from the midgut lumen to the salivary duct for the infection of a healthy plant to occur.

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Santos, Fabiano Aparecido dos. "Capacidade e mecanismos de dispersão do ácaro-vermelho-do-amendoim Tetranychus ogmophallos (Acari: Tetranychidae)." Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/154823.

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O cultivo do amendoim está sujeito a vários estresses por fatores seja de natureza biótica ou abiótica. Entre os fatores bióticos que afetam o desenvolvimento das plantas, destacam-se a ocorrência de pragas e doenças que limitam a produtividade da cultura. O ácaro Tetranychus ogmophallos é uma praga emergente que vêm causando prejuízos aos produtores de amendoim nas safras de 2008/09 até 2017/18. Até a realização desta pesquisa pouco se sabia sobre o potencial e capacidade de dispersão desta espécie de ácaro. Compreender os mecanismos de dispersão de um organismo praga é fundamental para estabelecimento de estratégias de controle. Portanto, o objetivo principal dos trabalhos foi estudar os mecanismos de dispersão de T. ogmophallos na cultura do amendoim. Os experimentos foram conduzidos no Laboratório de Acarologia do Departamento de Fitossanidade da Universidade Estadual Paulista - Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal (UNESP/FCAV). Para avaliar a dispersão de T. ogmophallos pelo vento foram realizados dois experimentos com níveis de infestação diferentes, 500 e 1.000 indivíduos por planta. A dispersão foi avaliada submetendo-se os ácaros a velocidades de vento (vv) de 5, 10, 15, 20, 25 e 30 km.h-1. O número de ácaros capturados foi avaliado para cálculo da distância média de deslocamento e a porcentagem de ácaros deslocados. A porcentagem de ácaros deslocados (AD%) foi estimada em função de vv a partir de quatro modelos não lineares. Os resultados indicaram que AD% depende de vv existindo uma velocidade a qual o deslocamento é maximizado. Também concluímos que o modelo de Shepherd (1982) é o que melhor se ajusta aos fatores relacionados a dispersão de T. ogmophallos. Um último experimento foi realizado para avaliar a ação da teia sobre a dispersão de T. ogmophallos. Nesse experimento foram utilizadas plantas jovens com duas folhas cada, cultivadas em vasos de 10 litros. Uma estaca de madeira foi utilizada para conduzir as plantas, amarrando-as com uma fita de plástico. Um pedaço de papel milimetrado foi fixado próximo à extremidade superior da estaca com a finalidade de calibrar o software utilizado para dimensionar a formação de teia (Image J ®). Em cada planta foram transferidas quarenta fêmeas adultas utilizando um pincel de uma única cerda. Assim que os ácaros iniciaram a formação de teias na extremidade da estaca, estas foram fotografadas diariamente com o uso de uma câmera fotográfica Nikon Coolpix P510 até a remoção dos aglomerados de teia (collective silk balls). As imagens foram submetidas ao software Image J® para avaliar o perímetro e o volume dos aglomerados de teia. Os aglomerados de teia foram retirados das estacas e transferidas para placas de Petri. Após a transferência foi quantificado o número de ácaros das camadas internas e externas dos aglomerados. No estudo dos aglomerados de teia concluímos que há a necessidade de um número mínimo de ácaros que caminham sobre a estaca para a formação dos aglomerados. Também concluímos que a formação dos aglomerados fornece risco de mortalidade aos ácaros, entretanto, garante que seja feita uma dispersão em um número relativamente grande de indivíduos.
Peanut crop is subject to several stresses by factors of a biotic or abiotic nature. Among the biotic factors that affect the development of plants, we highlight the occurrence of pests and diseases that limit the productivity of the crop. The mite Tetranychus ogmophallos is an emerging pest that has been causing losses to peanut farmers in the 2008/09 crop season until 2017/18. Until the realization of this research little was known about the potential and dispersion capacity of this species of mite. Understanding the mechanisms of dispersion of a pest organism is critical for the establishment of control strategies. Therefore, the main objective of the work was to study the mechanisms of dispersion of T. ogmophallos in the peanut crop. The experiments were conducted at the Laboratory of Acarology of the Department of Plant Protection of the São Paulo State University (UNESP), School of Agricultural and Veterinarian Sciences, Jaboticabal. To evaluate the dispersion of T. ogmophallos by wind two experiments were carried out with different infestation levels, 500 and 1,000 individuals per plant. The dispersion was evaluated by subjecting the mites at wind speeds (ws) of 5, 10, 15, 20, 25 and 30 km.h-1. The number of mites captured was evaluated for the calculation of mean displacement distance and the percentage of displaced mites. The percentage of displaced mites (AD%) was estimated as a function of ws from four non-linear models. The results indicated that AD% depends on ws for a velocity at which displacement is maximized. We also conclude that the Shepherd (1982) model best fits factors related to the dispersion of T. ogmophallos. Another experiment was carried out to evaluate the action of the web on the dispersion of T. ogmophallos. In this experiment were used young plants with two leaves each, grown in 10 liter pots. A wooden stake was used to drive the plants, tying them with a plastic tape. A piece of graph paper was attached near the top edge of the stake for the purpose of calibrating the software used to size the web (Image J ®). In each plant forty adult females were transferred using a single bristle brush. As the mites began to form webs at the edge of the stake, they were photographed daily with the use of a Nikon Coolpix P510 camera until the removal of the collective silk balls. The images were submitted to Image J® software to evaluate the perimeter and volume of collective silk balls. The collective silk balls were removed from the cuttings and transferred to Petri dishes. After the transfer was quantified the number of mites of the internal and external layers of the collective silk balls. In the study of collective silk balls, we concluded that there is a need for a minimum number of mites that walk on the stake for the formation of collective silk balls. We also conclude that formation provides a risk of mortality to mites, however, it ensures dispersal in a relatively large number of individuals.

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Chiguachi, Juliana Andrea Martinez. "Preferência hospedeira e desempenho do ácaro branco em pimenta malagueta e em plantas espontâneas." Universidade Federal de Viçosa, 2014. http://locus.ufv.br/handle/123456789/3992.

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Broad mite, Polyphagotarsonemus latus (Banks, 1904) (Acari: Tarsonemidae), is distinguished for being a polyphagous pest, cosmopolitan and for have been founded attacking various cultures of global importance including the Capsicum frutescens chili pepper crops. Due to the damage caused farmers incur inappropriate practices in an attempt to control this pest. Thus, there is a necessity to find alternatives to control that pest to have success in the management and reduce the damage. Keeping weeds is a strategy that can increase populations of beneficial arthropods by rendering a most suitable environment for the development of these organisms due to the availabilíty of food resources. However, this can serve as an alternative vegetation shelter to phytophagous by offering food and adequate conditions to remain in the agroecossitema, and generate potential for development of insect pests. Therefore, in this study was aimed to determine the interactions among weeds found in the agroecosystems of chilli pepper and the phytophagous mite P. latus. This study is divided in three parts. In Chapter 1, is described the identification of the main west found in chilli pepper crops associated with P. latus, and the role of those plants on mite infestations in the crop. In chapter 2, was evaluated the potential for host-white mite species by Weeds found in agroecosystems of chili, and was determined the influence of plant breeding mite acceptance of host plants. According to the results obtained in the field, the infestation of P. latus in areas of Chili peppers with presence of weeds was significant compared with areas wíthout weeds. Weeds of Vernonia polysphaera, Ageratum conyzoides, Triumfetta bartramia and C.bonaeriensis.were found with P. latus. There were significant differences in the presence of P. latus in the time assessment. Weeds were significantly affected by the presence of P. latus. Significant difference was observed between the instantaneous population growth rates of P. latus (r¡) between the different plant species evaluated finding plants of C. frutescens, T. bartramia and A. conyzoides with higher population growth at the time assessment. With the study about the potential for host plants of P. latus, showed a significant difference in the amount of dust mites that come off of the whitefly, according to the origin of the creation of dust mites. Mites had a greater acceptance by plants of T. bartramia, V. polysphaera and C. frutescens. The weeds associated with culture of chili peppers may favor the presence of the mite-white. The maintenance of plants V. polysphaera, A. conyzoides e T. bartramia, C. bonaeriensis growing on the field can increase the potential for development, and alternative hosts as a refuge for the mite-white, by the reproductive success and acceptance of different weeds.
O ácaro-branco, Polyphagotarsonemus latus (Banks, 1904) (Acari: Tarsonemidae), destaca-se por ser praga polifaga, cosmopolita e ter sido encontrada atacando várias culturas de importância mundial entre elas o cultivo de Capsicum frutescens pimenta- malagueta. Devido aos danos causados os agricultores incorrem em práticas inadequadas na tentativa de controle desta praga. Desta forma, há a necessidade de se encontrar alternativas ao controle da praga para diminuir os danos causados. A manutenção de plantas espontâneas é uma estratégia que permite aumentar populações de artrópodes benéficos ao tornar o ambiente mais adequado para estes, devido à disponibilidade de recursos alimentares. No entanto, essa vegetação pode servir como abrigo alternativo para fitófagos pelo oferecimento de alimento e condições adequadas para permanecer no agroecossitema, e gerar potencial para o desenvolvimento de pragas. Assim, neste trabalho, foi proposto determinar as interações entre plantas espontâneas encontradas dentro do agroecossistema de pimenta-malagueta e o ácaro fitófago P. latus. No Capítulo 1 é descrita a importância da presença de plantas espontâneas na cultura de pimenta-malagueta e avaliação da sua influência sobre as infestações do ácaro-branco dentro da cultura, foram identificadas as principais plantas espontâneas integradas ao plantio de pimenta com presença do ácaro-branco,e avaliado o potencial de crescimentos de P. latus em plantas espontâneas e de pimenta-malagueta a traves da taxa instantânea de crescimento populacional (r¡) sob condições de laboratório. No capitulo 2 foi avaliado o potencial de hospedeiro ao ácaro-branco por espécies de plantas espontâneas encontradas no agroecossistema da pimenta-malagueta, e foi determinada a influência da planta de criação do ácaro na aceitação de plantas hospedeiras. De acordo com os resultados obtidos em campo, a infestação de P. latus em áreas de pimenta-malagueta com presença de plantas espontâneas foi significativa comparada com áreas sem plantas espontâneas. Plantas espontâneas de Vernonia polysphaera, Ageratum Conyzoides, Triumfetta bartramia e Conyza bonaeriensis, foram encontradas Com P. latus. Houve diferença significativa na presença de P. latus no tempo de avaliação. Plantas espontâneas foram afetadas significativamente pela presença de P. latus. Houve diferença significativa entre as taxas instantâneas de crescimento populacional de P. latus(r¡) entre as diferentes espécies de plantas avaliadas encontrando plantas de C. frutescens, T. bartramia e A. conyzoides com maior crescimento populacional no tempo de avaliação. Com o estudo sobre o potencial de plantas hospedeiras de P. latus, mostrou diferença significativa na quantidade de ácaros que se desprendem da mosca-branca, de acordo com a origem de criação dos ácaros. Os ácaros tiveram uma maior aceitação por plantas de T. bartramia, V. Polysphaera e C. frutescens. As plantas espontâneas associadas a cultura da pimenta-malagueta podem favorecer a presença do ácaro-branco. A manutenção de plantas V. polysphaera, A. conyzoides e T. bartramia, C. bonaeriensis, no campo de cultivo pode aumentar o potencial de desenvolvimento, e hospedeiros alternativos como refugio para o ácaro- branco, pelo sucesso reprodutivo e aceitação de diferentes plantas espontâneas.

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Bush, Catherine Dana. "Native seed mixes for diverse plant communities." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ28920.pdf.

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26

Roggia, Samuel. "Caracterização de fatores determinantes dos aumentos populacionais de ácaros tetraniquídeos em soja." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-29112010-090801/.

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Ácaros tetraniquídeos são considerados pragas secundárias em soja, no entanto, nos últimos anos, foram registrados ataques severos e freqüentes destes em diferentes regiões produtoras do Brasil. Experimentos foram realizados em campo e laboratório com o objetivo de estudar os fatores determinantes dos aumentos populacionais de ácaros tetraniquídeos em soja. Para determinar se cultivares transgênicas de soja seriam mais susceptíveis aos ácaros, foi estudado o ciclo biológico e a tabela de vida dos ácaros Mononychellus planki (McGregor) e Tetranychus urticae Koch em três cultivares de soja transgênicas, glifosato-tolerante, e três não-transgênicas com elevada semelhança genética às respectivas cultivares transgênicas. Testes de toxicidade foram realizados em laboratório com agrotóxicos comumente utilizados em soja para determinar os efeitos destes sobre importantes inimigos naturais dos ácaros tetraniquídeos e das lagartas da soja, os fungos Neozygites floridana e Nomuraea rileyi, respectivamente. Em campo, durante duas safras agrícolas (2007/2008 e 2008/2009), foi estudado o efeito de cinco manejos fitossanitários sobre a flutuação populacional de ácaros tetraniquídeos, lagartas, percevejos fitófagos e de alguns de seus inimigos naturais. As cultivares transgênicas não afetaram significativamente o ciclo biológico de M. planki e T. urticae e as pequenas diferenças observadas para alguns parâmetros da tabela de vida destas espécies entre cultivares não estão relacionadas à modificação genética. A avaliação do efeito dos agrotóxicos sobre os patógenos revelou que o fungicida Alto 100 e o herbicida Roundup Ready inibiram o crescimento micelial de N. rileyi. Para N. floridana todos os fungicidas contendo estrubirulinas inibiram completamente a esporulação, enquanto que os produtos do grupo dos triazóis resultaram em taxas intermediárias de esporulação e germinação de conídios. A espécie M. planki foi mais abundante do que T. urticae em campo. O ácaro predador Neoseiulus anonymus e o fungo N. floridana foram os inimigos naturais associados a estes ácaros pragas. Os fungicidas Priori Xtra e Alto 100 reduziram a prevalência de N. floridana, mas não interferiram na dinâmica de N. anonymus. O inseticida piretróide Decis 25 EC reduziu a densidade deste predador, mas não afetou o fungo. No tratamento onde foram aplicados os fungicidas com o inseticida observou-se aumentos populacionais de ácaros fitófagos. A pulverização do herbicida glifosato não afetou N. anonymus e N. floridana, e a presença de plantas daninhas favoreceu o predador. Os picos populacionais mais elevados de Anticarsia gemmatalis foram observados em 2008/09, nas parcelas onde foram empregados fungicidas, e maiores densidades de Pseudoplusia includens foram observadas no tratamento com Decis 25 EC. A aplicação deste inseticida também afetou negativamente a densidade de insetos predadores e resultou em maiores densidades de percevejos fitófagos. O herbicida glifosato não afetou a densidade de pragas e inimigos naturais, no entanto, a presença de plantas daninhas favoreceu os insetos predadores e desfavoreceu os percevejos fitófagos. Em geral, os estudos em campo indicam que o uso de fungicidas e inseticidas são fatores associados aos aumentos populacionais de ácaros em soja.
Spider mites are secondary pests of soybean, however, recently outbreaks has frequently been reported on different producing regions of Brazil. Experiments were carried out in field and laboratory aiming to determine the main factors associates with spider mite outbreaks in soybean. To determine if genetically modified (GM) soybean varieties are more susceptible to spider mites, the life cycle and life table of the mites Mononychellus planki and Tetranychus urticae was studied on three GM soybean cultivars glyphosate-tolerant and three non-transgenic cultivars genetically similar to the transgenic ones. Toxicological tests were carried out in laboratory with pesticides commonly used in soybean to determine the pesticide effect on important natural enemies of spider mites and soybean catterpillars, the fungi Neozygites floridana and Nomuraea rileyi, respectively. In the field during two growing seasons (2007/2008 and 2008/2009), the effects of five plant protection managements were studied on the population dynamics of spider mites, caterpillars, stink bugs and some of their natural enemies. The transgenic cultivars did not significantly affect the life cycle parameters of M. planki e T. urticae and differences observed for some life table parameters between cultivars are not related to the genetic modification. Evaluation of the effect of pesticides on the pathogens showed that the fungicide Alto 100 and the herbicide Roundup Ready inhibited the mycelial growth of N. rileyi. Against N. floridana, all fungicides with strobilurins completely inhibited sporulation, while the triazole products hence showed intermediate rates of sporulation and conidia germination. The spider mite M. planki was more abundant than T. urticae in the field. The predatory mite Neoseiulus anonymus and the fungus N. floridana were the main natural enemies associated to these mite pests. The fungicides Priori Xtra and Alto 100 reduced the prevalence of N. floridana, though this pesticide did not negatively affected N. anonymus. The pyrethroid insecticide Decis 25 EC reduced the density of this predator, but did not affect the fungus. The treatment where fungicides and the insecticide were applied, increases on populations of phytophagous mites were observed. Spraying of the herbicide glyphosate did not affect N. anonymus and N. floridana, and the presence of weeds favored the predator. Higher population peaks of Anticarsia gemmatalis were associated with fungicide applications in 2008/09 and higher densities of Pseudoplusia includens were observed in treatment with Decis 25 EC. This insecticide also negatively affected the density of predatory insects and resulted on higher densities of stink bugs. The herbicide glyphosate did not affect density of pests and natural enemies; however, the presence of weeds favored insect predators, and resulted on lower populations of stink bugs. Overall, the field studies indicate that the use of fungicides and insecticides are important factors associated to spider mite outbreaks in soybean.

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Carswell, Leslie. "Fungi associated with plant deaths in rehabilitated bauxite mines." Thesis, Carswell, Leslie (1993) Fungi associated with plant deaths in rehabilitated bauxite mines. Honours thesis, Murdoch University, 1993. https://researchrepository.murdoch.edu.au/id/eprint/32821/.

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Alcoa of Australia is committed to reintroduce 80% of the jarrah forest plant. species back onto rehabilitated bauxite mines in south western Australia by 1997. It has been observed that plant deaths do occur on these mines. The aim of this project was to determine if plant pathogens were responsible for these deaths. Healthy, sick and dying plants were sampled over a 5 week period initiated in February 1993. The following isolates were obtained from 19 plant species: 25 Fusarium spp., 11 Botryosporium sp., 8 Bdtryosphaeria ribis, 5 Cytospora eucalypticola, 6 Phoma spp. isolates, 5 Gelasinospora spp., 4 Diaporthe sp., 4 Pestalotiopsis sp., 3 Phonzopsis spp., 1 Dichomera eucalypti, 1 Phytophthora sp., 1 Monochaetia sp. and 1 Botrytis cinerea isolate. Many other fungi were isolated but could not be identified. Not all isolates were tested in glasshouse or field pathogenicity trials. Two B. ribis isolates were lesion forming in glasshouse trials. Gelasinospora, C. eucalypticola, Botryosporium and D. eucalypti were not lesion forming but were reisolated from the wound tissue, indicating that these fungi had the potential to be pathogenic. Field trials initiated in June (winter) (duration of 3-6 weeks) showed 3 B. ribis, 1 C. eucalypticola, and 1 Phoma sp. isolates to be lesion forming. Many isolates were not lesion forming including B. ribis, C. eucalypticola, Diaporthe, Botryosporium, Phoma, Phomopsis, D. eucalypti, and Fusarium but were reisolated from wound tissue, indicating they have the potential to be pathogens. Environmental conditions were felt to be responsible for the lack of lesions in the plants and it was recommended that these pathogenicity tests be repeated in summer, when environmental conditions are likely to be conducive to disease.

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Medeiros, Marcos Barros de. "Ação de biofertilizantes líquidos sobre a bioecologia do ácaro Brevipalpus phoenicis." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-30122002-103839/.

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Esta pesquisa foi conduzida para avaliar os efeitos de interações entre a planta hospedeira e um biofertilizante líquido sobre o ácaro Brevipalpus phoenicis (Geijskes). Primeiramente avaliaram-se os efeitos residual e sistêmico de biofertilizantes aplicados a plantas de Canaialia etlçifbrmis (L.) DC. sobre parâmetros bioecológicos de uma população de B. phoenicis. Para o efeito residual foram testados os seguintes tratamentos: a) Água destilada (Controle); b) Biofert -- biofertilizante produzido em um único bioreactor; e) Biornix - uma mistura com biol@ertilizantes produzidos em quatro bioreatores; e d) Bio+VL - Biofert + Verticillium leca;,iii (Zimm.) Viégas. Para o efeito sistêmico somente dois tratamentos foram avaliados: a) Biofert e b) Água destilada (Controle). A seguida avaliou-se a interação tópica e residual entre concentrações do biofertilízante nas plantas hospedeiras: C. ensíformis e Ligustnim lucindum Aiton. Utilizando-se n-úcroscopia eletrônica de varredura (MEV), caracterizaram-se as manifestações patológicas sobre os cadáveres de 8. phoenicis. Foram observados efeitos adversos do biofertilizante sobre os parânietros de sobrevivência e de oviposição. A taxa líquida de reprodução (Ro)foi de 18,1; 12,9; 12,5 e 10,5 fêmea/fêmea (efeito residual) e 19,4 e 13,0 fêmea/fêrnea (efeito sistêmico), respectivamente para os tratamentos nas ordens supra mencionadas. Tanto na ação residual quanto via sistêmica houve redução significativa do potencial de crescimento populacional de B. phoenicis. Nas duas plantas hospedeiras a sobrevivência e oviposição do ácaro foram significativamente reduzidas com o aw-nento de concentração do biofertilizante, sendo mais severo em C ensijbrmis. Evidenciou-se uma colonização microbiana nos ácaros mortos pela ação do biofertilizante e também verificou-se que um composto coloidal do biofertilizante causou imobilização e obstrução do sistema digestivo do ácaro. A interação entre a planta hospedeira e o biofertilizante, numa relação de equilíbrio trofobiótico, contribui para um melhor manejo desse ácaro.
This study was conducted to evaluate interactions between host plants and the effect of biofertilizers on Brevipalpits phoeiiicis (Geijskes) bioecology. The residual and systemic effects of biofertilizer mjxtures sprayed on Canavalia ensiformis (L.) DC. plants on the bioecology parameters were firstly evaluated. For the residual effect bioassay the following treaúnents were tested: a) Distilled water (Control); b) Biofert biofertilizer produced in a single bioreactor; e) Biomix - a mix of biofertilizers produced in four bioreactors; and d) Bio+VL - Biofei-t, + Verticilliuin lecanii (Zimm.) Viégas. For tbe systemic effect bloassay two stispensions were tested: a) Biofert and b) Distilled water (Control). Thereafter the topical and residual interaction effects between concentrations of the biofertilizer and C. ensiformis and Ligustrum lucidum Aiton. Host plants were evaluated. Were also characterized pathological manifestations in the dead mites by using seanning electronic microscopy images. Adverse effects of biofertilizers on both survival and oviposition parameters were verified. The net reproduction rates (Ro) were 18.09; 12.92; 12.52 and 10.52 female/female (residual effect) and 19.42 and 13.00 female/female (systemic effect), respectively, for the treatments in the above mentioned orders. The results showed that the biofertilizers reduced the potential population growth of B. phoenicis in the residual and in the systemie effect assays. The biofertilizer demonstrated deleterious effect on fertility and survival of R. phoenicis on both host plants, mostly on C ens@formis. The mites dead by biofertilizer action showed evidences of microbial colonization. A colloidal coinpound of biofertilizer induced mite immobilization and obstruction in its digestivo tract. The interaction between host plant and biofertilizer deleterious effects will contribute to enhance mite management based on trophobiotic relationships.

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Gomes-Silva, Flavio. "Evolução de acarodomácias em Bignonieae (Bignoniaceae)." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/41/41132/tde-24022010-112022/.

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Acarodomácias (ou domácias foliares) são cavidades ou tufos de tricomas localizados nas axilas entre as nervuras na face abaxial das folhas. Por meio dessas estruturas, várias espécies de angiospermas lenhosas estabelecem um mutualismo com ácaros benéficos (fungívoros e predadores). Nessa simbiose, as domácias foliares fornecem abrigo e proteção aos ácaros contra inimigos naturais e dessecação, enquanto os ácaros protegem as plantas contra fungos patogênicos e artrópodes fitófagos. Essas estruturas estão presentes em várias espécies da tribo Bignonieae (Bignoniaceae), um grupo monofilético com cerca de 382 espécies de lianas e arbustos neotropicais. A notável variedade de acarodomácias na tribo, somada à disponibilidade de uma filogenia robusta do grupo, torna Bignonieae um excelente modelo para investigar a evolução dessas estruturas. O presente trabalho visou caracterizar as acarodomácias de Bignonieae e estudar a evolução dessas estruturas no grupo. Além disso, realizou testes de correlação entre a evolução de acarodomácias e a de outras características potencialmente associadas à acarofilia: pilosidade foliolar e nectários extraflorais (NEFs). As acarodomácias estão presentes em 58 das 103 espécies analisadas, abrangendo 12 dos 20 gêneros da tribo presentes na filogenia. Foi constatada a presença de domácias primárias, secundárias e terciárias, e dos componentes bolso, tricomas e cova. A variação intra-específica constatada para esses caracteres foi marcante. Além disso, todos eles revelaram-se homoplásticos (múltiplas evoluções e reversões). Foi encontrada uma correlação positiva entre os padrões de evolução de domácias primárias, secundárias e terciárias, e um surgimento sequencial dessas estruturas: primeiro surgiram as domácias primárias, depois as secundárias e, por fim, as terciárias. Quanto aos componentes, bolso e tricomas mostraram-se onipresentes e revelaram uma evolução correlacionada; a evolução do componente cova, por sua vez, não se mostrou correlacionada a dos outros componentes. O padrão de evolução de pilosidade foliolar revelou que, em geral, primeiro surgiram tricomas sobre as nervuras e, posteriormente, os tricomas se estenderam pela lâmina. A evolução de acarodomácias também se mostrou correlacionada à de pilosidade foliolar. É possível que a pilosidade e as acarodomácias atuem em conjunto no mutualismo planta-ácaro benéfico. Adicionalmente, constatou-se que as evoluções de acarodomácias estão sempre relacionadas à presença de tricomas, sugerindo que os tricomas devem ter uma papel especial na acarofilia. Não se observou correlação entre a evolução de domácias foliares e a de NEFs. Este estudo representa o primeiro trabalho sobre a evolução de acarodomácias, e traz importantes subsídios para pesquisas futuras sobre diferentes aspectos da biologia dessas estruturas em Bignonieae, especialmente no que tange a interação planta-ácaro benéfico.
Acarodomatia (or leaf domatia) are cavities or hair tufts found on the axils of veins on the abaxial surface of leaves. Several species of woody angiosperms mediate a mutualism with benefic mites (fungivorous and predaceous) through these structures. In this symbiotic relation, the leaf domatia provide refuge and protection to mites against natural enemies and desiccating conditions, while the mites protect the plants against pathogenic fungi and phytophagous arthropods. These structures are present in many species of the tribe Bignonieae (Bignoniaceae), a monophyletic group with approximately 382 species of neotropical lianas and shrubs. The wide variation of acarodomatia in the tribe associated with the availability of a robust phylogeny for the group makes Bignonieae an excellent model to address the evolution of these structures. The objective of this study was to characterize the acarodomatia of Bignonieae and investigate the evolution of these structures in the group. Furthermore, this study intended to test for correlated patterns of evolution between leaf domatia and traits potentially associated with acarophily: leaflet pubescence and extra floral nectaries (EFNs). Acarodomatia were found in 58 of the 103 analyzed species, representing 12 of the 20 genera of Bignonieae sampled within the phylogeny of the group. Primary, secondary and tertiary domatia were encountered, as well three different domatia components: pocket, trichomes and pit. High intraspecific variation was encountered in those traits. Furthermore, high homoplasy was also encountered, with multiple evolutions and reversals of each trait being documented. A positive correlation in the pattern of evolution of the primary, secondary and tertiary domatia was found, as well as a sequential evolution of these structures: first primary domatia evolved, which was followed by the evolution of secondary domatia and, subsequently the evolution of tertiary domatia. As far as the components of the acarodomatia are concerned, pockets and trichomes were omnipresent and their evolutionary pattern correlated. The evolution of the pit, on the other hand, was not associated to the evolution of any of the other components. The evolutionary pattern of leaf pubescence indicated that, in general, trichomes over the veins of the leaflets evolved first and subsequently spread throughout the blade. The evolutionary pattern of acarodomatia was also shown to be correlated with the evolution of leaflet pubescence. It is possible that pubescence and acarodomatia might act together to promote a beneficial plant-mite mutualism. In addition, the multiple origins of the acarodomatia were always associated with the presence of trichomes, suggesting that trichomes must have had an important role in acarophily. No correlation was found between the evolution of leaf domatia and the evolution of EFNs. This study represents the first investigation of the evolution of acarodomatia, and brings important contributions for future studies on different aspects of the biology of these structures in Bignonieae, especially in what concerns the beneficial association between plants and mites.

30

Nott, Christopher James. "Biomarkers in ombrotrophic mires as palaeoclimate indicators." Thesis, University of Bristol, 2000. http://hdl.handle.net/1983/7d4ac25d-664f-48ec-868e-343bc77eb09d.

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31

Asmara, Degi Harja. "Agroforestry on post-mining restoration : a challenge beyond plant mixture systems." Doctoral thesis, Université Laval, 2020. http://hdl.handle.net/20.500.11794/67442.

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L'agroforesterie est un système dynamique d'aménagement écologique des ressources naturelles renouvelables, qui en intégrant les espèces ligneuses aux champs agricoles, fermes et autres paysages, diversifie, augmente la production et engendre des bénéfices socioéconomiques et environnementaux. En tant que solution pour la fourniture des services écosystémiques, son application à la restauration des écosystèmes dégradés, endommagés ou détruits devient très importante. Les terres dégradées, endommagées ou détruites (3-D) par l’exploitation minière sont caractérisées par un sol de faible fertilité et parfois des niveaux élevés des contaminants. Ces conditions les rendent difficile l'obtention d'un avantage à court terme de l'agroforesterie en comparaison aux terres arables, mais sa principale fonction restaurative consistant à rétablir les services écosystémiques et à accroître la résilience peut être bénéfique à long terme. Le défi consiste à développer la meilleure stratégie pour accélérer la productivité des plantes tout en améliorant le sol et l’écosystème grâce à une combinaison des techniques d’ingénierie écologique pour la biorestauration des milieux miniers. Nous explorons ici le mélange de plantes, d’inoculation microbienne et d’amendement en biochar, dans un système agroforestier ligneux-herbacé. L’objectif est de trouver le meilleur scénario de biorestauration à partir des effets combinés de mélange de plantes et d’autres facteurs écologiques connexes. Des recherches antérieures sur l'agroforesterie et la restauration ont été révisées à travers le monde entier, y compris l’application du concept agroforestier en biorestauration des terres post-minières. La stratégie de restauration connue dans un milieu donné ne constitue pas une solution universelle. Ainsi, l'identification de tout aspect important des travaux antérieurs sur la restauration et l'agroforesterie est cruciale. La stratégie de mélange des plantes est un facteur important dans les processus de succession. Dans cette recherche, nous avons appliqué le concept de parcelles de Nelder modifié pour la combinaison d'espèces de plantes dans une expérience en serre sur les stériles et les résidus fins afin d'explorer l'interaction au début de la plantation. Nous avons aussi appliqué l’inoculum microbien et le biochar sur le mélange de plantes dans des essais en serre et sur le terrain sur les stériles et les résidus fins comme matériau de sol d’un site post-extraction de l’or. La performance de la co-plantation de quatre espèces ligneuses (Alnus viridis (Chaix) DC. ssp. crispa (Aiton) Turrill, Picea glauca (Moench) Voss, Populus tremuloides Michx. et Salix arbusculoides Andersson) avec les les espèces de plantes herbacées (Avena sativa L., Festuca rubra L. et Trifolium repens L.) a été évaluée. Le mélange de plantes est un principe très important dans les pratiques de restauration, étant donné son rôle connu pour augmenter la biodiversité et la diversité fonctionnelle dans le système écologique durable. Bien que la stratégie de mélange ait été rarement explorée, nous avons constaté que la combinaison des espèces avait un effet neutre (ni avantages, ni inconvénients) par rapport à une seule espèce dans l’expérience de parcelles de Nelder. En même temps, l'effet positif de la densité suggérait que l'amélioration du microclimat avait joué un rôle dans la croissance précoce des plantations. L'essai sur le terrain confirme l'effet positif de la modification du microclimat sur la productivité des plantes lorsque la densité de plantation est élevée. Le compromis sur la concurrence des plantes a montré que la densité la plus élevée ne constitue pas nécessairement une condition optimale pour la productivité des plantes. L'effet d'interaction du biochar et du traitement d'inoculation montre l'intérêt de ce traitement, mais l'impact varie selon la densité de plantation. La densité de plantation a été démontrée comme le facteur le plus important pour générer l'effet positif net. Nous suggérons que le mécanisme était corrélé à l'amélioration du microclimat par la conservation de l'eau des plantes du sol et l'amélioration de l'activité microbienne par rapport à la modification de la température du sol. Par conséquent, mettre l'accent sur l'amélioration du microclimat, ainsi que sur d'autres facteurs combinés, y compris l'inoculation microbienne et l'amendement du biochar, est très important pour accélérer les processus de restauration.
Agroforestry is a dynamic system of ecological management of renewable natural resources, which by integrating woody species into agricultural fields, farms and other landscapes, diversifies and sustains production for increased socio-economic and environmental benefits. As a solution for the provision of ecosystem services, its application to the restoration of degraded damaged, or destroyed ecosystems becomes very important. Degraded, damaged, or destroyed (3-D) lands by mining is characterized by low fertility soil and sometimes high levels of contaminants. These conditions make them difficult to obtain a short-term advantage from agroforestry compared to arable lands, but its main restorative function of restoring ecosystem services and increasing resilience can be beneficial in the long term. The challenge is to develop the best strategy to accelerate plant productivity while improving the soil and the ecosystem through a combination of ecological engineering techniques for bioremediation of mining areas. Here we explore the mixture of plants, microbial inoculation, and biochar amendment, in a woody-herbaceous agroforestry system. The goal is to find the best bioremediation scenario from the combined effects of mixing plants and other related ecological factors. Previous research on agroforestry and restoration has been reviewed worldwide, including the application of the agroforestry concept in bioremediation of post-mining land area. The known restoration strategy in a given environment is not a universal solution. Thus, the identification of any important aspect of previous work on restoration and agroforestry is crucial. The strategy of mixing plants is an important factor in the successional process. But a statistical accounting of plant-plant interactions and adaptation to multi-species conditions is hard to achieve in field experiments; trials under controlled conditions can distinguish effects of planting density and species interactions in the early stages of plant establishment. In this research, we applied the concept of modified Nelder plots for the combination of plant species in a greenhouse experiment on waste rock and fine tailing to explore the interaction at the start of planting. We also applied microbial inoculum and biochar to the plant mixture in greenhouse and field tests on waste rock and fine tailing as soil material on a post-gold mining site. The performance of the co-planting of four woody species: green alder (Alnus viridis (Chaix) DC. ssp. crispa (Aiton) Turrill); white spruce (Picea glauca (Moench) Voss); trembling aspen (Populus tremuloides Michaux); and littletree willow (Salix arbusculoides Andersson) with the herbaceous plant species: oat (Avena sativa L.); red fescue (Festuca rubra L.) and white clover (Trifolium repens L.) was evaluated. Mixing plants is a very important principle in restoration practices, given its known role to increase biodiversity and functional diversity in the sustainable ecological system. Although the plant mixing strategy has been rarely explored, we have found no mixture provided advantages for both species in paired combinations. At the same time, the positive effect of the density on plant growth suggested that the microclimate improvement had played a role in the early growth of the plantations. The field trial confirms the positive effect of the microclimate modification on plant productivity in higher planting density. The trade-off on plant competition has shown, however, that the highest density does not necessarily show an optimal condition for plant productivity. The interaction effect of biochar and inoculation treatment shows the benefit of this treatment, although the impact varies according to the density of planting. The plantation density was shown as the most important factor in generating the net positive effect. We suggest that the mechanism was correlated with the microclimate improvement through soil plant water conservation and microbial activity enhancement over soil temperature modification. Hence, putting emphasis on microclimate improvement, along with other combined factors including microbial inoculation and biochar amendment is very important for accelerating the restoration processes

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Paljic, Alexis. "Interaction en environnements immersifs et retours d'effort passifs." Paris 6, 2004. https://hal-mines-paristech.archives-ouvertes.fr/tel-01479203.

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Penn, R. M. "Soil water and plant growth on restored opencast coalmine sites." Thesis, University of Nottingham, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383765.

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Oliphant, Adam J. "Mapping Elaeagnus Umbellata on Coal Surface Mines using Multitemporal Landsat Imagery." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/75119.

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Invasive plant species threaten native plant communities and inhibit efforts to restore disturbed landscapes. Surface coal mines in the Appalachian Mountains are some of the most disturbed landscapes in North America. Moreover, there is not a comprehensive understanding of the land cover characteristics of post- mined lands in Appalachia. Better information on mined lands' vegetative cover and ecosystem recovery status is necessary for implementation of effective environmental management practices. The invasive autumn olive (Elaeagnus umbellata) is abundant on former coal surface mines, often outcompeting native trees due to its faster growth rate. The frequent revisit time and spatial and spectral resolution of Landsat satellites make Landsat imagery well suited for mapping and characterizing land cover and forest recovery on former coal surface mines. I performed a multitemporal classification using a random forest analysis to map autumn olive on former and current surface coal mines in southwest Virginia. Imagery from the Operational Land Imager on Landsat 8 were used as input data for the study. Calibration and validation data for use in model development were obtained using high-resolution aerial imagery. Results indicate that autumn olive cover is sufficiently dense to enable detection using Landsat imagery on approximately 12.6% of the current and former surface coal mines located in the study area that have been mined since the early 1980s. The classified map produced here had a user's and producer's accuracy of 85.3% and 78.6% respectively for the autumn olive coverage class. Overall accuracy in reference to an independent validation dataset was 96.8%. These results indicate that autumn olive growing on reclaimed coal mines in Virginia and elsewhere in the Appalachian coalfields can be mapped using Landsat imagery. Additionally, autumn olive occurrence is a significant landscape feature on former surface coal mines in the Virginia coalfields.
Master of Science

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Krco, Zeljko. "Interaction between mine and plant in coal processing /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18633.pdf.

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Best, Russell. "U.S. City Climate Action Plans: Planning to Reduce Vehicle Miles Traveled?" University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1427982751.

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Light, Fritz. "ALOE STRIATA PLANT DEFENSE COMPOUNDS PRODUCED IN RESPONSE TO JASMONIC ACID, SALICYLIC ACID, AND ERIOPHYID MITE SALIVARY EXTRACT ELICITOR COMPOUNDS." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/836.

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Aloe mites are herbivores of the genus Aloe (ALOACEAE) and are associated with hyperplastic growth in various aloe species, but the biochemistry of this interaction is poorly understood. In an effort to characterize plant defense responses to herbivory in the genus Aloe, a salivary extract was isolated from aloe mites (Aceria aloinis Keifer) and its bioactivity was tested using a hypocotyl elongation assay. Subsequently, Aloe striata plants were treated with jasmonic acid (JA), salicylic acid (SA), and the mite salivary extract. Using water and methanol, compounds of different polarity were extracted from aloe tissues that had been frozen and crushed at 4, 12, and 24h after treatment. Extracts were analyzed by HPLC and three compounds were found. One of these compounds was SA (mean concentration of 4µg/mL), and this is the first time that this aloe species has been found to produce SA. Two additional peaks of unknown identity were observed in JA- and SA-treated plants. These results suggest that A. striata may in fact undergo a JA-mediated change in secondary metabolism as part of a plant defense response.

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Mikkelä, Catharina. "Methane emission from Swedish mires - in relation to different spatial and temporal scales /." Umeå : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5645-2.pdf.

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39

Brown, Carol A. "Biomass production, composition, and ethanol potential of switchgrass grown on reclaimed surface mines in West Virginia." Thesis, West Virginia University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1573301.

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Growing crops for biofuel production on agricultural land has caused a debate between whether we should grow corn grain on productive, agricultural lands to feed a growing human population or to fuel our vehicles. This has increased interest in growing cellulosic biofuel feedstocks on marginal lands. Switchgrass (Panicum virgatum L.), a warm-season perennial grass, has been shown to be a viable bioenergy crop because it produces high yields on marginal lands under low water and nutrient conditions. West Virginia contains immense acreages of reclaimed surface mine lands and could offer enough area for the production of switchgrass as a feedstock for a biofuel industry.

The first study was established in 2008 to determine switchgrass yields of three different cultivars on two mine sites in West Virginia. The first site, which was reclaimed in the early 1990s using top soil and treated municipal sludge, consistently had the highest yield of the two sites with a sixth-year yield of 8.4 Mg Dry Matter (DM) ha^-1 averaged across varieties. Cave-in-Rock variety produced 13.0 Mg ha^-1 of biomass which was more than the other two varieties. The other site, Hobet, was prepared using crushed, unweathered sandstone in 2008 and average yields were 1.0 Mg ha^-1 for the sixth year of production.

The second study was conducted on two sites which were reclaimed with a layer of topsoil over gray overburden and seeded with Cave-in-Rock 2011. Fertilizer was applied at rates of 0, 33.6, and 67 kg N ha^-1. No fertilizer treatment yielded 0.32 Mg ha^-1 while the fertilizer treatments produced significantly higher yields.

The objective of the third study was to determine if cultivars and samples from fertilizer treatments differed in composition and theoretical ethanol yield. Compositional analysis was done using near infrared reflectance spectroscopy. It was determined that cultivars did not differ in theoretical ethanol yield with averages ranging from 364 to 438 L Mg^-1. Theoretical ethanol production from Cave-in-Rock was significantly higher ranging from 6,092 to 7,348 L ha^-1 due to its high biomass production. Fertilizer treatments did not greatly effect composition of switchgrass, but since it did improve yield this was reflected in greater ethanol production for fertilized treatments. Based on the information presented here, high biomass should be the goal for switchgrass grown for biofuel production. With proper soil substrate and fertilizer regime, switchgrass grown on reclaimed surface mines may have high enough yield and quality to support ethanol production in the future.

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Penacchio, Olivier. "Structures de Hodge mixtes et fibrés sur le plan projectif complexe." Toulouse 3, 2002. http://thesesups.ups-tlse.fr/1709/.

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Le développement de la théorie de Hodge a permis une compréhension plus profonde de nombreux invariants topologiques dans le cadre de la géométrie algébrique complexe. Dans ce travail de thèse, nous nous proposons de géométriser la notion de structure de Hodge mixte (SHM). Dans ce but, nous généralisons la construction de Rees et son inverse qui permettent d'associer anneaux gradués et anneaux filtrés par une chaîne d'idéaux. Nous établissons des équivalences entre catégories d'espaces vectoriels filtrés munies de morphismes strictement compatibles et catégories de faisceaux cohérents équivariants pour l'action d'un tore. Le fait que des filtrations soient opposées se traduit géométriquement par une condition de semi-stabilité forte des fibrés associés. Cette correspondance est appliquée pour exhiber une équivalence entre la catégorie des SHMs et une catégorie de fibrés vectoriels semi-stables sur le plan projectif complexe. Nous vérifions que cette dernière catégorie est abélienne, ce qui nous donne donc une démonstration géométrique du fait que la catégorie des SHMs est abélienne, un des points de départ de la théorie de Hodge mixtes, démontré par P. Deligne. Un nouvel invariant des SHMs, le niveau de R-scindement, est alors défini et ses propriétés sont étudiées. Cet invariant est calculé pour des SHMs sur les premiers groupes de cohomologie de courbes de genre 0 et 1 possiblement singulières et non-complètes. Nous étudions aussi une version relative de la correspondance pour l'appliquer aux variations de SHMs. Cette correspondance ne fonctionne que modulo une stratification adéquate de la base
Hodge theory has provided a deeper understanding of many topological invariants in complex algebraic geometry. The proposal of this thesis is to find a geometric equivalent of mixed Hodge structures (MHSs). Therefore, we generalize a construction by Rees that associates a graded ring to a ring filtered by a chain of ideals. This allows us to establish equivalences between categories of filtered vector spaces endowed with morphisms that are strictly compatible and categories of coherent sheaves that are equivariant for the action of a torus. The fact that filtrations are opposed translates into a strong semistability condition for the associated vector bundles. The equivalence is next applied to MHSs and yields an equivalence between the category of MHSs and a category of semistable vector bundles on the complex projective plane. This last category is shown to be Abelian, which provides a geometric proof that the category of MHSs is Abelian. We next define a new invariant of MHSs, the R-split level, and study its properties. We compute this invariant for singular and non-complete curves of genus 0 and 1. We study a relative version of the equivalence, which aims at describing variations of MHSs geometrically. This correspondence only works provided a good stratification of the base is chosen

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Grau, Calle Juan Miguel, Moyano Fernando Morón, and Aguado César Rigoberto Yupari. "Plan estratégico de la Corporación Minera Fortuna Silver Mines 2016-2025." Master's thesis, Universidad del Pacífico, 2016. http://hdl.handle.net/11354/1466.

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Fortuna Silver Mines Inc. (FSM) fue fundada en el año 2005 en Vancouver, Canadá, e inicia su participación en el mercado de capitales en la bolsa de Toronto (TSX). El mismo año compra la operación minera Caylloma en el Perú y en el año 2006 la referida mina reinicia sus operaciones comerciales, luego de haberse rehabilitado para las nuevas exigencias. En términos de fuentes primarias, se ha utilizado información de la página web de FSM, recalcando que esta corporación cotiza en las bolsas de Toronto (TSX) y de Nueva York (NYSE), motivo por el cual la información que consigna es consistente y pública, además es constantemente auditada y regulada por la Canadian Securities Administrators (CSA) y la Securities and Exchange Commission (SEC), ambas entidades reguladoras del mercado de valores de Canadá y Estados Unidos, respectivamente. Por el aspecto corporativo de la presente investigación, necesariamente se hacen referencias obligatorias, como por ejemplo sobre las comparaciones de la gobernanza de FSM con los principios del gobierno corporativo de la OCDE, la gestión de riesgos con el COSO 2013 y el alineamiento de las estrategias con las 7s de McKinsey, las que no necesariamente son avaladas por FSM. También cabe mencionar que los cálculos de producción de minerales es un ensayo con fines académicos, sustentado en las reservas y recursos de mineral que tiene FSM y que proponemos ampliar como parte del incremento de la cuota de mercado, a fin de cumplir con la visión. Los datos usados en el flujo de caja son asumidos solo con el rigor académico, y no son datos proveídos por FSM.

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Marra, Michael A. "Switchgrass potential on reclaimed surface mines for biofuel production in West Virginia." Thesis, West Virginia University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1522523.

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The high cost and environmental risks associated with non-renewable energy sources has caused an increased interest in, and development of renewable biofuels. Switchgrass (Panicum virgatum L.), a warm season perennial grass, has been investigated as a source of biofuel feedstock due to its high biomass production on marginal soils, its tolerance of harsh growing conditions, and its ability to provide habitat for wildlife and soil conservation cover. West Virginia contains vast expanses of reclaimed surface mine lands and could potentially benefit from the production of switchgrass as a biofuel feedstock. Furthermore, switchgrass production could satisfy Surface Mining Reclamation and Control Act of 1977 (SMCRA) requirements for reclamation bond release to mine operators. Three separate studies will be discussed in this thesis to determine if switchgrass grown on reclaimed surface mines can produce yields similar to yields from stands grown under normal agronomic conditions and what common surface mining reclamation practices may be most appropriate for growing switchgrass. The first study examined yield production of three commercially-available, upland switchgrass varieties grown on two reclaimed surface mines in production years two, three and four. The Hampshire Hill mine site, which was reclaimed in the late 1990s using top soil and treated municipal sludge, averaged 5,800 kg (ha-yr)^-1 of switchgrass compared to 803 kg (ha-yr)^-1 at the Hobet 21 site which was reclaimed with crushed, unweathered rock over compacted overburden. Site and variety interacted with Cave-in-Rock as the top performer at the more fertile Hampshire Hill site and Shawnee produced the highest yields at Hobet 21 (7,853 kg ha^-1 and 1,086 kg ha^-1 averaged across years, respectively). Switchgrass yields increased from 2009 to 2010, but declined from 2010 to 2011. Switchgrass yields from farmlands in this region averaged about 15000 kg (ha-yr)^-1 in the research literature, so switchgrass grown on reclaimed lands appears to be about 50% lower. A second study to determine optimal nitrogen and mulch rates for switchgrass establishment began in June 2011 on two newly-reclaimed surface mines. Both sites were seeded at a rate of 11.2 kg pure live seed (PLS) ha^-1 of Cave-in-Rock on replicated treatments of 0, 33.6 and 67.0 kg N ha^-1, and high and low mulch rates of mulch applied as hydromulch. Switchgrass cover, frequency and yield improved with the addition of any amount of N fertilizer compared to no N application. There was no significant difference in yield associated with high and low levels of N. We also observed that yields were not affected by application of additional mulch. The final study compared a one- and two-harvest system in the fourth year of production at the Hampshire Hill and Hobet 21 sites. There was no increase in yield production utilizing a two-harvest system (2922 kg (ha-yr)^-1, averaged across site) compared to a one-harvest system (3029 kg (ha-yr)^-1). The data also showed that re-growth collected from July to October in the two-harvest system added negligible yield and that yield collected in July was comparable in one- and two-harvest systems.

43

Lanterman, Jessie L. "Re-establishment of Wild Bee Communities on Reclaimed Ohio Coal Mines." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1500453116904491.

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44

Nogueira, Márcia Dimov. "Análise de perigos e pontos críticos de controle no processamento de farinha de trigo integral." Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-03082017-175539/.

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O Sistema de Análise de Perigos e Pontos Críticos de Controle (APPCC) ou Hazard Analysis Critical Control Point (HACCP) é de grande importância para a Saúde Pública, quanto às doenças veiculadas por alimentos. O objetivo deste trabalho foi verificar a aplicabilidade do uso desse sistema na indústria de moagem de trigo, no processamento de farinha de trigo integral, produto com demanda crescente no mercado. Trinta produções de farinha foram coletadas numa indústria cuja capacidade de moagem é de 15ton./h na cidade de São Paulo. A população amostrada foi de 30 sub-amostras de trigo argentino (A) (12,8% de umidade média), 17 sub-amostras de trigo brasileiro (B) (13,1% de umidade média), 30 sub-amostras de trigo preparado para moagem (M) (15,6% de umidade média) e 30 sub-amostras de farinha de trigo integral (FTI), coletadas num período de 5 meses (de outubro de 97 à março de 98). A metodologia utilizada para pesquisa de sujidades leves foi a adotada pelos Métodos Oficiais da AOAC (1995). Houve modificações no método e um estudo foi realizado para conhecer sua performance. No isolamento de fungos foi utilizada a metodologia empregada pela AOAC/FDA Bacteriological Analytical manual (1992). Para identificação de fungos em relação ao gênero foi utilizado o método preconizado GELLI et al.(1990), SAMSON et al (1995), PITT and HOCKING (1997). Na análise de sujidades leves nos trigos foi evidenciada a contaminação por ácaros (A=90%, B=53%, M=77% e FTI=53%); no trigo argentino houve uma predominância para a família Tarsonemidae, enquanto que na respectiva farinha foi a família Acaridae. Alguns ácaros dessa última família estão implicados em reações alérgicas e estão sendo tratados como emergentes na segurança alimentar. Os insetos thisanópteros, os mais freqüentes nos trigos, foram eliminados na farinha de trigo integral. O percentual médio de contaminação fúngica dos grãos foi de A=99%, B=95% e M=94%. O principal gênero encontrado foi Aspergillus spp (A= 79,0%, B= 39,3% e M= 64,2%). O menos freqüente Fusarium spp (A= 2,9%, B= 2,7% e M=1,5%). Na farinha de trigo integral o principal gênero encontrado foi o Penicillium spp e o Fusarium não foi isolado. O desoxinivalenol foi encontrado em uma amostra de farinha de trigo integral a uma concentração de 231 ng/g. O sistema APPCC se aplica aos moinhos e os auxilia a controlar suas produções do ponto de vista da segurança alimentar.
Food safety is a major concern facing the food industry today. Hazard Analysis Critical Control Point (HACCP) provides a structured approach to the assurance of safety of products. The aim of this study was to verify the use of HACCP system in a milling industry, precisely in the whole wheat flour production. At first step two hazards were analyzed: deoxynivalenol and allergenic mites in whole wheat flour Thirty (30) lots of flour were collected in an industry which capacity was 15 ton./h in São Paulo city. Those lots had 30 sub-samples of argentine (A) wheat (12,8% average moisture content), 17 sub-samples of brazilian (B) wheat (13,1% m.c.), 30 sub-samples of wheat for milling (M) (15,6% m.c), and 30 sub-samples of whole wheat flour (FTI) that were analyzed in a five months period (from 97/october to 98/march). Light filth was isolated from grains and flour, according to Official Methods of AOAC International. Methodology of extraction of light filth from whole wheat flour was studied to know the repeatability according to AOAC methods. Fungi isolation was performed according to AOAC/FDA Bacteriological Analytical Manual (1992) methodology; genera were identified according GELLI et al.(1990), SAMSON et al (1995), and PITI and HOCKING (1997). Detection and quantification of deoxynivalenol (DON) were done by thin layer chromatography (TLC) according to SABINO et al. (1989).The most significant light filth contamination in wheat were mites (A= 90%, B= 53%, M= 77% e FTI= 57%), argentine wheat had as a predominant mite the family Tarsonemidae and flour had Acaridae. The average fungal contamination in grains was 99%, 95% e 94% in argentine, brazilian and wheat for milling respectively. The predominant genera was Aspergillus spp ( A= 79,0, B=39,3% e M= 64,2 %), and Fusarium was the least frequent in wheat (A>/b>=2,7%, B= 2,8% e M=1,5%). Only one lot of whole wheat flour was contaminated by DON at level 231 ng/g. This study showed that HACCP system is appropriated for control hazards in milling industry. However, DON should be controlled before wheat get into industry, and this control need to be registered. Mites are new emergentes to cause allergy by ingestion and have to be controlled by GMP procedures.

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Kopittke, Peter Martin. "Limitations to plant root growth in highly saline and alkaline bauxite residue /." [St. Lucia, Qld.], 2004. http://adt.library.uq.edu.au/public/adt-QU20040913.094109/index.html.

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Paspati, Angeliki. "Living on an unfriendly plant host: impact of tomato on the predatory mite Amblyseius swirskii." Doctoral thesis, Universitat Jaume I, 2019. http://hdl.handle.net/10803/668347.

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Abstract:

The predatory mite Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) is a key player in the biological control of pests in greenhouse crops. However, on tomato crops, the release of A. swirskii does not provide effective pest control, as it cannot become established. In summary, this study concludes that the acyl sugars produced by tomato trichomes are detrimental to the phytoseid A. swirskii, and this information can serve as a basis for future research in plant breeding programs, with the aim of a successful application of phytoseids for the protection of tomato crops. In addition, the impact of current mass breeding practices on the genetic variation of A. swirskii was demonstrated and the review and innovation of these practices, in order to achieve maximum performance of biocontol agents in pest management was suggested.
Un enemigo natural clave en el control biológico de plagas en cultivos de invernadero es el ácaro depredador Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae). Sin embargo, en los cultivos de tomate, la liberación de A. swirskii no proporciona un control efectivo de las plagas, ya que no puede establecerse. En resumen, en este estudio se concluye que los acil azúcares producidos por los tricomas de tomate son perjudiciales para el fitoseido A. swirskii, y esta información puede servir como base para futuras investigaciones en programas de fitomejoramiento, con el objetivo de una aplicación exitosa de fitoseidos para la protección de cultivos de tomate. Además, la demostración del impacto de las prácticas actuales de cría en masa sobre la variación genética de A. swirskii, sugiere la revisión e innovación de estas prácticas, con el fin de lograr el máximo rendimiento de los agentes de biocontol en el manejo de plagas.

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Prėskienis, Vilmantas. "Holocene development and permafrost history of two mires in Tavvavuoma, Northern Sweden." Thesis, Stockholms universitet, Institutionen för naturgeografi och kvartärgeologi (INK), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-92709.

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Abstract:

Two peat cores from two mires with different characteristics, but both containingpermafrost features and located in the eastern part of the Tavvavuoma mire complex innorthernmost Sweden, were analysed for macrofossils and geochemical properties. Local vegetationsequences and changes in geochemical properties of peat were used to reconstruct development ofthe studied mires during the Holocene. The study includes measurements of water/ice content, bulkdensity, loss-on-ignition and C/N ratio. Radiocarbon dates for peatland inception and permafrostaggradation are available. The main purpose of the study is to verify permafrost history in thepeatlands. The results of the macrofossil analysis and values of C/N ratio indicate nutrient poor tointermediate fen environments in both studied mires until recently. Signs of permafrost upheavalwhich caused formation of xerophilic peat can be proved only since late 1950’s. The study resultscorroborate with other studies from Northern Fennoscandia and infer peatland initiation soon afterthe deglaciation of the area and permafrost-free conditions throughout entire Holocene untilrecently.

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Ruggles, Thomas Alan. "Plant communities on reclaimed surface mines in Northeast Ohio: Effects of succession and nitrogen-fixing autumn olive." Kent State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=kent1574681631819824.

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49

Rethwisch, Michael D., Krystyl Bolin, Jessica L. Grudovich, Jessica Wellman, Dyke Charles Van, Juan Vingochea, Marlo Barron, and Mark Reay. "Effect of two-spotted spider mites and miticides on alfalfa hay produced for a late May cutting." College of Agriculture, University of Arizona (Tucson, AZ), 2004. http://hdl.handle.net/10150/203870.

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Abstract:

Three miticide treatments (milbemectin, clarified neem oil, and chlorpyrifos plus dimethoate) were compared with an untreated check to obtain information on the effects of twospotted spider mite (Tetranychus urticae) feeding on alfalfa yields, quality and economics, as well as crop responses to miticides. Mite infested alfalfa was treated just prior to first irrigation after cutting in spring 2003, and numbers of spider mites and western flower thrips (Frankliniella occidentalis) were obtained at weekly intervals thereafter for the next seven weeks. Data for plant parameters (stem widths, numbers of leaves, internode lengths) were obtained at harvest, as were hay yields and quality. The milbemectin treatment resulted in quickest reduction of spider mites (88.5% at 5 days after application) and also resulted in significantly higher yields than the untreated check (0.18 tons of hay/acre), attributed to the longer internodes and resultant tallest plants and significantly thicker stems than the untreated check. Clarified neem oil and chlorpyrifos plus dimethoate treatments did not control spider mites as quickly as milbemectin and yields were increased by only 0.04-0.05 tons hay per acre in this experiment compared with the untreated check. These two treatments also differed in their effects on stem widths and internode lengths, indicating that some results noted were a result of interactions of miticides with alfalfa as well as spider mite control.

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Lybbert, Andrew H. "Temporal Dynamics of Seeded, Native Adventive, and Non-Native Vegetation in Plant-Pollinator Interaction Networks on Reclaimed Mines." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1595512084426782.

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Dissertations / Theses on the topic 'Plant mites'

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