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1
Jenkins, Tim A. "Fungal biological control of Hieracium." Thesis, University of Canterbury. Microbiology, 1995. http://hdl.handle.net/10092/4841.
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Hieracium species are a severe weed problem in the high country native tussock grasslands of New Zealand. This thesis reports on the potential for fungal biological control of Hieracium, in particular with a rust pathogen, Puccinia hieracii var. piloselloidarum. Isolates of Hieracium rust were collected from throughout Northern, Central and
Southern Europe, and the British Isles. One thousand four hundred and twenty four
isolates were screened on New Zealand Hieracium pilosella to identify the most
infective strains for potential use as biological control agents. The rust isolates most
pathogenic to New Zealand H. pilosella, were from the south of Ireland. They had a
shorter latent period and higher infectivity compared to other isolates. One isolate
infected representatives of all New Zealand H. pilosella sites as well as H. praealtum
and H. x stoloniflorum.
Hieracium rust was common throughout Europe with large seasonal fluctuations.
Most dissemination, infection and effect was seen in a main peak in spring and a
secondary peak in autumn. The rust could survive through winter conditions within
host tissue allowing rapid re-establishment of symptoms during occasional periods of
suitable milder weather and, eventually, with the onset of spring. In an intensive field
study of one Edinburgh area, the level of rust infection on patches of H. pilosella was
found to be affected by several site factors, particularly the density of patches.
The infection process of Hieracium rust was studied. Spore germination was fastest
in the dark and occurred over a wide range of temperatures. Inoculations of hosts was
either on to detached leaves kept on water agar or on to whole rosettes. Infection of
detached leaves was generally higher than on whole rosettes and may allow a wider
host range of subgenus Pilosella taxa. Infection rarely occurred on all inoculated
plants. This was attributed in part to the effect of host condition. A genetic resistance
component of the non-susceptibility remains possible although one rust isolate was
able to infect representatives of all identified genotypes of New Zealand H. pilosella.
The variation present in New Zealand Hieracium species was investigated by
chromosome analysis and isozyme electrophoresis. H. pilosella from 34 collections
throughout New Zealand were predominantly pentaploid with a hexaploid found in
just one population; the pentaploids included variants, according to electrophoresis
results and morphological characters.
Hieracium rust showed potential as a biological control agent. The rust significantly
affected the growth of H. pilosella and displayed strict host-specificity, with no hosts
outside the subgenus Pilosella.
Powdery mildew, Erysiphe cichoracearum, is common and very pathogenic on
Hieracium spp. throughout Europe. However, Hieracium powdery mildew grew on
two New Zealand endemic species, Embergeria grandi/olia and Kirkianella novaezelandiae.
Several other Hieracium pathogens were noted but their potential for
biological control requires further investigation.
2
Koomen, Irene. "Biological control of Colletotrichum gloeosporioides." Thesis, University of Kent, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278551.
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Colletotrichum gloeosporioides is the causal agent of anthracnose disease of mangoes. Infection occurs when humidity is high and rain-dispersed spores germinate and form an appressorium on immature mangoes. The infection then becomes quiescent until the fruit is harvested. On ripe fruit infection is visible as black, sunken lesions on the surface. At the pre-harvest stage, the disease is controlled with the application of a range of fungicides, and at the post-harvest stage by hot benomyl treatment. The extensive use of benomyl, both pre- and post-harvest, has resulted in the occurrence of isolates of C. gloeosporioides resistant to this fungicide. To devise an alternative strategy of disease control, the potential for biological control of anthracnose has been investigated. Potential microbial antagonists of C. gloeosporioides were isolated from blossom, leaves and fruit of mango, and screened using a series of assay techniques. In total 650 microorganisms, including bacteria, yeasts and filamentous fungi, were isolated and tested for their inhibition of growth of C. gloeosporioides on malt extract agar. Of these 650 isolates, 121 inhibited the fungus and were further tested on their ability to inhibit spore germination in vitro. Of these, 45 isolates, all bacteria and yeasts, were inoculated onto mangoes, which were artificially inoculated with C. gloeosporioides, and assessed for their potential to reduce the development of anthracnose lesions. A further selection was made, and 7 isolates were chosen to be used in a semi-commercial trial in the Philippines. This final screening procedure yielded two potential candidates for field trials, isolate 204 (identified as Bacillus cereus) and isolate 558 (identified as Pseudomonas fiuorescens). A field trial involving pre-harvest application of the biological control agent, was conducted using isolate 558. This isolate was chosen for this purpose since in in vitro experiments it significantly reduced germination of C. gloeosporioides spores. In the field trial 558 was applied in combination with nutrients and compared to treatments which had received no treatment or which had received conventional fungicide (benomyl) application. On spraying, high numbers of 558 were recorded on the leaf surface, but no reduction in post-harvest development of disease was observed. Failure of disease control was attributed to rapid death of the bacterium on the phylloplane. Inpost-harvest trials, isolates 204 and 558 were both tested in combination with different application methods, including the addition of sticker, peptone, fruit wax or a sucrose polyester. Application of 204 did not reduce disease development. Application of 558, however, did significantly reduce anthracnose development compared to the control fruit. No additional benefit was achieved by incorporating the bacteria in peptone, fruit wax or sucrose polyester. The mode of action of isolate 558 was investigated in detail. There was no evidence for parasitism taking place, or the production of volatile compounds, in the suppression of disease development. No antibiotic compounds were detected, but isolate 558 did produce a siderophore. A sharp increase in pH was also observed in culture media in which 558 was grown. Disease control may result from a combination of these two factors.
3
Mutinda, Irene. "Biological control of mignonette weeds." Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266625.
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Sano, Michael Benjamin. "Electromagnetic Control of Biological Assembly." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/76975.
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We have developed a new biofabrication process in which the precise control of bacterial motion is used to fabricate customizable networks of cellulose nanofibrils. This work describes how the motion of Acetobacter xylinum can be controlled by electric fields while the bacteria simultaneously produce nanocellulose, resulting in networks with aligned fibers. Since the electrolysis of water due to the application of electric fields produces the oxygen in the culture media far from the liquid-air boundary, aerobic cellulose production in 3D structures is readily achievable. Five separate sets of experiments were conducted to demonstrate the assembly of nanocellulose by Acetobacter xylinum in the presence of electric fields in micro and macro environments. This work demonstrates a new concept of bottom up material synthesis by control of a biological assembly process.Master of Science
5
Garcia, André Filipe Fidalgo Casquilho. "Enhancing biological control against Eucalyptus pests." Doctoral thesis, ISA, 2020. http://hdl.handle.net/10400.5/21212.
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Lordan, Sanahuja Jaume. "Enhancing biological control in apple orchards." Doctoral thesis, Universitat de Lleida, 2014. http://hdl.handle.net/10803/275941.
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La tisoreta comuna Forficula auricularia Linnaeus i Forficula pubescens Gené (Dermaptera : Forficulidae ) poden tenir un paper decisiu com a depredadors. Es va observar compatibilitat entre la tisoreta i nematodes entomopatògens (NEPs) i una activitat dissuassòria en larves de carpocapsa Cydia pomonella L. (Lepidoptera: Tortricidae) mortes per NEPs, reduint l’alimentació de la tisoreta sobre cadàvers que contenien nematodes al seu interior. La presència de tisoretes i aranyes (Araneae) es va observar all llarg de tot l’any, però tan sols les tisoretes van contribuir a reduir les infestacions de pugó llanut. Les re-infestacions procedents de colònies subterrànies no resulten ser rellevants en les regions mediterrànies. D’aquesta manera, el control d'aquest pugó cal que estigui dirigit tant cap a les colònies aèries com a les arrels.
L'ús d’infraestructures ecològiques pot augmentar el control biològic de plagues, proporcionant un entorn més favorable i aliments i refugis alternatius als enemics naturals. Anacyclus clavatus Desf., Dorycnium pentaphyllium Scop., Erucastrum nasturtiifolium Poiret, Euphorbia serrata L., Hedysarum confertum Desf., Papaver rhoeas L., Trifolium pratense L. a la primavera, i Atriplex sp., Dittrichia viscosa L., Medicago sativa L., Moricandia arvensis L., Salsola kali L., Sorghum halepense (L.) Pers., Suaeda spicata Willd. i Verbena sp. a la tardor poden proporcionar refugi i aliment a les aranyes. Viburnum tinus L., Euonymous japonicus L. fil. i Pistacia lentiscus L. van mostrar resultats prometedors per a augmentar la riquesa i abundància d'enemics naturals.La tijereta común Forficula auricularia Linnaeus y Forficula pubescens Gené (Dermaptera : Forficulidae ) pueden tener un papel decisivo como depredadores. Se observó compatibilidad entre la tijereta y nematodos entomopatógenos (NEPs) y una actividad disuasoria en larvas de carpocapsa Cydia pomonella L. (Lepidoptera: Tortricidae) muertas por NEPs, reduciendo la alimentación de la tijereta sobre cadáveres que contenían nematodos en su interior. La presencia de tijeretas y arañas (Araneae) se observó durante todo el año, pero sólo las tijeretas contribuyeron a reducir las infestaciones de pulgón lanígero. Las re-infestaciones procedentes de colonias subterráneas no resultan ser relevantes en las regiones mediterráneas. El control de este pulgón debe dirigirse tanto hacia las colonias aéreas como a las subterráneas. El uso de infraestructuras ecológicas puede aumentar el control biológico de plagas, proporcionando un entorno más favorable y alimentos y refugios alternativos a los enemigos naturales. Anacyclus clavatus Desf., Dorycnium pentaphyllium Scop., Erucastrum nasturtiifolium Poiret, Euphorbia serrata L., Hedysarum confertum Desf., Papaver rhoeas L., Trifolium pratense L. en primavera, y Atriplex sp., Dittrichia viscosa L., Medicago sativa L., Moricandia arvensis L., Salsola kali L., Sorghum halepense ( L. ) Pers., Suaeda spicata Willd. y Verbena sp. en otoño pueden proporcionar refugio y alimento a las arañas. Viburnum tinus L., Euonymous japonicus L. fil. y Pistacia lentiscus L. mostraron resultados prometedores para aumentar la riqueza y abundancia de enemigos naturales.
The European earwig Forficula auricularia Linnaeus and Forficula pubescens Gené (Dermaptera: Forficulidae) may play a crucial role as biocontrol predators. Compatibility between European earwig and entomopathogenic nematodes (EPN) and an earwig deterrent activity in EPN-killed codling moth Cydia pomonella L. (Lepidoptera: Tortricidae) larvae that reduces the foraging of European earwig on insect cadavers containing nematodes was also observed, suggesting compatibility between the European earwig and EPNs was observed. European earwigs and spiders (Araneae) were found throughout the year, but only earwigs contributed to reduce woolly apple aphid infestations. Reinfestations from root colonies are not relevant in Mediterranean areas. The use of ecological infrastructures may increase the biological control of pests, providing a more favorable environment and additional food and shelters for natural enemies. Anacyclus clavatus Desf., Dorycnium pentaphyllium Scop., Erucastrum nasturtiifolium Poiret, Euphorbia serrata L., Hedysarum confertum Desf., Papaver rhoeas L., Trifolium pratense L. in spring, and Atriplex sp., Dittrichia viscosa L., Medicago sativa L., Moricandia arvensis L., Salsola kali L., Sorghum halepense (L.) Pers., Suaeda spicata Willd. and Verbena sp. in fall were observed as native flora useful to provide shelter and food for spiders. Viburnum tinus L., Euonymous japonicus L. fil. and Pistacia lentiscus L. showed promising results in order to enhance abundance and richness of natural enemies.
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Li, Weiwei. "Optimal control for biological movement systems." Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3205051.
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Thesis (Ph. D.)--University of California, San Diego, 2006.Title from first page of PDF file (viewed April 4, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 131-146).
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Brenner, Sibylle. "Mechanistic Control of Biological Redox Systems." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.518447.
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Mpofu, Bellah. "Biological control of waterhyacinth in Zimbabwe." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40203.
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In a survey conducted in Zimbabwe in 1993, waterhyacinth was present in seven out of the eight provinces. No control measures were imposed on 35% of the infested dams and 61% of the infested rivers, while in 47% of the infested dams and 11% of the infested rivers control of waterhyacinth was being attempted with a combination of 2,4-D and mechanical control methods. The population of Neochetina eichhorniae and N. bruchi declined during the period 1993 to 1995 in the Hunyani River system. Several fungi were isolated from diseased waterhyacinth, and Fusarium moniliforme (isolate 2ex 12), F. solani (isolates 5a ex25 and 2a3), and F. pallidoroseum (isolate 3ex1) were found to be the most pathogenic. Large numbers of viable conidia were produced in shake-flask liquid fermentation with modified Richard's medium and in solid fermentation with food grains. Conidia production in straw was poor with the exception of waterhyacinth straw. Host range studies conducted in pots and in the field indicated that Commelina benghalensis was moderately susceptible to both isolates of F. solani in the field, while Setaria verticilata grown in pots was moderately susceptible to isolate 2a3. Brassica rapa and Crotalaria juncea grown in pots were moderately susceptible to F. moniliforme but they showed no infection in the field. Fifty-nine additional plant species of ecological and agricultural importance were not susceptible to the Fusarium species. When F. solani, F. pallidoroseum and Neochetina spp. were used individually in ponds, they did not control waterhyacinth. When the fungi were combined with Neochetina spp., the area covered by waterhyacinth and the volume of waterhyacinth were significantly reduced.
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Hartfield, Christopher Mark. "Biological control of aphids on plum." Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287493.
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Pamphilon, Lindsay Victoria. "The biological control of Myzus cerasi." Thesis, University of Greenwich, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325268.
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Rackauckas, Christopher Vincent. "Simulation and Control of Biological Stochasticity." Thesis, University of California, Irvine, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10827971.
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Stochastic models of biochemical interactions elucidate essential properties of the network which are not accessible to deterministic modeling. In this thesis it is described how a network motif, the proportional-reversibility interaction with active intermediate states, gives rise to the ability for the variance of biochemical signals to be controlled without changing the mean, a property designated as mean-independent noise control (MINC). This noise control is demonstrated to be essential for macro-scale biological processes via spatial models of the zebrafish hindbrain boundary sharpening. Additionally, the ability to deduce noise origin from the aggregate noise properties is shown.
However, these large-scale stochastic models of developmental processes required significant advances in the methodology and tooling for solving stochastic differential equations. Two improvements to stochastic integration methods, an efficient method for time stepping adaptivity on high order stochastic Runge-Kutta methods termed Rejection Sampling with Memory (RSwM) and optimal-stability stochastic Runge-Kutta methods, are combined to give over 1000 times speedups on biological models over previously used methodologies. In addition, a new software for solving differential equations in the Julia programming language is detailed. Its unique features for handling complex biological models, along with its high performance (routinely benchmarking as faster than classic C++ and Fortran integrators of similar implementations) and new methods, give rise to an accessible tool for simulation of large-scale stochastic biological models.
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Safronova, D. "Biological method for water quality control." Thesis, Видавництво СумДУ, 2012. http://essuir.sumdu.edu.ua/handle/123456789/26726.
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Problem
Saint-Petersburg is located at the Neva river and almost all drinking water for 5 million inhabitants is taken from it. Talking about water supply centralised source for Saint-Petersburg, one can mark a lot of negative factors influencing the water quality. Surely, agricultural pollution, transport and economical problems are among them.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/26726
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Barclay, Cameron G. "The biological control of cervical ripening." Thesis, University of Edinburgh, 1995. http://hdl.handle.net/1842/20597.
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A cell culture system was developed to study the production of prostaglandins by cervical cells from late pregnant guinea pigs. This permitted the examination of the influence of various substances on the synthesis of the prostaglandins, including progesterone and the anti-progesterone drug RU486 (Mifepristone/RU38486). RU486 has been found to promote cervical ripening in humans and guinea pigs. It is thought to increase the sensitivity of the uterus to prostaglandins and thereby promote muscle activity. It is licensed in the United Kingdom as an abortifacient. Since this antiprogestin can provoke cervical ripening alone an accessible source of tissue from an animal with a similar physiology to the human seemed to be an appropriate starting point from which to investigate the effects of this steroidal derivative and how it may affect prostaglandin production. The results show that prostaglandin output can be provoked in vitro by agents such as lipopolysaccharide and phorbol ester. The observed effects by RU486 were mixed. Giving the animals examined, there were, however, some instances where a significant increase was detected, apparently associated with the calcium ionophore A23187, and others where there appeared to be a reduction. The inclusion of RU486 in the culture medium with other treatments did not produce any significant differences compared to the treatment on its own, and alone RU486 only produced a significant difference where the animal had been given the drug in vivo.
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CINQUERRUI, ALESSANDRO. "Sustainable approaches to control Calonectria diseases in ornamental nursery." Doctoral thesis, Università degli studi di Catania, 2015. http://hdl.handle.net/20.500.11769/490912.
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Le specie appartenenti al genere Calonectria sono importanti patogeni delle piante ornamentali. La lotta chimica per il controllo delle malattie causate da tali patogeni è necessaria, ma allo stato attuale è importante ricercare strategie di controllo alternative alla lotta chimica, che consentano di rispettare le recenti normative europee sull’uso sostenibile dei pesticidi (Dir. 2009/128/EC). Diversi esperimenti sono stati messi in atto per la messa a punto di programmi di lotta integrata (IPM) che consentano un efficace contenimento delle infezioni in vivaio, quali macchie fogliari, marciumi e tacche necrotiche del fusto, marciumi del colletto e delle radici, causate da diverse specie di Calonectria su differenti specie ospiti. Le prove preliminari in vitro hanno dimostrato una variabile attività antagonista di alcune specie di Trichoderma spp., Clonostachys rosea e Penicillium oxalicum nei confronti di diverse specie di Calonectria. I risultati degli esperimenti in vivo dimostrano che boscalid+pyraclostrobin e cyprodinil+fludioxonil, applicati in combinazione con agenti di controllo biologico (BCAs) appartenenti ai generi Bacillus, Trichoderma e Streptomyces siano in grado di assicurare un efficace contenimento delle infezioni causate da Calonectria spp. Tutti i trattamenti integrati e biologici sono risultati efficaci nel contenimento del marciume del fusto di Dodonaea viscosa, del marciume del colletto e delle radici su Polygala myrtyfolia e delle macchie fogliari su Metrosideros spp. e Callistemon spp. Poiché le specie appartenenti al genere Calonectria sono patogeni tellurici in grado di differenziare microsclerozi (che rappresentano l inoculo primario) nel suolo, la riduzione o soppressione di tale inoculo è un obiettivo cruciale per la gestione delle infezioni future. I primi esperimenti di fumigazione hanno dimostrato che l’applicazione di metham-sodium e dazomet a dosi di etichetta e dosi ridotte fornisce ottimi risultati nella riduzione della vitalità dei microsclerozi di Calonectria sia in microcosmo che in pieno campo. Inoltre, in conformità con la Dir. 2009/128/EC, diverse prove sono state condotte applicando questi fumiganti a dosi ancora più ridotte e utilizzando due film plastici (TIF e VIF) per la pacciamatura del suolo fumigato. I dati ottenuti hanno consentito di accertare che metham-sodio e dazomet applicati a dosi ulteriormente ridotte (fino a 5 volte inferiori) sono risultati efficaci nel ridurre la vitalità dei microsclerozi di Calonectria. Inoltre, l’applicazione di TIF ha consentito di ridurre la dose d impiego del fumigante, riducendo contemporaneamente l’emissione di gas inquinanti nell’atmosfera e l’impatto nella rizosfera. Complessivamente il film TIF ha mostrato una maggiore capacità di ritenzione rispetto a VIF.Calonectria species are important plant pathogens in ornamental plant nurseries. The chemical control of Calonectria diseases is necessary, but alternative management strategies would be re-evaluated to comply with the latest European Regulations on the Sustainable Use of Pesticides (Directive 2009/128/EC). Several experiments were carried out to develop integrated pest management (IPM) programs for controlling of leaf spot, stem rot and crown and root rot caused by several Calonectria species on several ornalmental plants. In vitro preliminary assays showed a variable antagonistic activity of some Trichoderma spp., Clonostachys rosea and Penicillium oxalicum. In vivo experiments showed that a good control of Calonectria diseases is achieved by applying boscalid+pyraclostrobin or cyprodinil+fludioxonil in combinations with different BCAs belonging to the genus Bacillus, Trichoderma and Streptomyces. All biological and integrated treatments were able to manage stem rot on Dodonaea viscosa, crown and root rot on Polygala myrtifolia and leaf spot on Metrosideros spp. and Callistemon spp. Since Calonectria species are soil-borne pathogens producing microsclerotia (that represent the primary inoculum) in the soil, the reduction or suppression of this inoculum is an important task of management of this pathogen. The first set of experiments of this PhD thesis on soil fumigation with metham-sodium and dazomet show clearly excellent performances in reducing Calonectria microsclerotia viability both in microcosm and in nursery when applied at label and sub-label rats. Moreover, in accordance with the Directive 2009/128/EC on the Sustainable Use of Pesticides , in these experiment these fumigants were applied at rates lower and lower and in association with gas-tight tarps, such as VIF and TIF. The data showed that in these conditions both fumigants were able to reduce Calonectria microsclerotia, with a consequent reduction of amount of fumigants (up to 5-fold reduced). In addition, the use of TIF barrier offered a better retain capacity of fumigant than VIF, with a lower emission of pollutant molecules to the atmosphere and a lower impact in rhizosphere.
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Colmenarez, Yelitza Coromoto [UNESP]. "Virulência de Thyrinteina arnobia virus (TaV) e de Bacillus thuringiensis à Thyrinteina arnobia (Lepidoptera: Geometridae): efeito da temperatura no desenvolvimento das lagartas e do pH da calda de pulverização." Universidade Estadual Paulista (UNESP), 2003. http://hdl.handle.net/11449/97243.
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colmenarez_yc_me_botfca.pdf: 214314 bytes, checksum: 6e85d2098f54ae999a6fd76ac5157948 (MD5)Este estudo teve por objetivo avaliar a eficiência do Thyrinteina arnobia vírus (TaV) e de Bacillus thuringiensis quando submetidos a diferentes condições de pH e temperatura no controle da lagarta parda Thyrinteina arnobia (Stoll, 1782) (Lepidoptera: Geometridae). Foram testadas 4 temperaturas (18, 22, 26 e 30º C) e 4 pHs diferentes (5, 6, 7 e 8). Os ovos de Thyrinteina arnobia foram provenientes de uma criação em dieta artificial, mantida em laboratório. Os entomopatógenos foram aplicados em folhas de Eucalyptus grandis, para posterior oferecimento à lagartas do 3º. e 5º. instares. O ensaio de pH foi conduzido em sala climatizada (temperatura: 25 ± 1oC ; UR: 70 ± 10 % e fotofase de 13 horas), enquanto que os ensaios de temperatura os tratamentos foram conduzidos em câmaras de BOD e fotofase de 13 horas. Os experimentos foram instalados no delineamento experimental inteiramente casualizado e a distribuição dos tratamentosem esquema fatorial 4x3, com 10 repetições de 5 lagartas cada uma, sendo avaliadas 150 lagartas para cada tratamento. Os dados obtidos foram submetidos à análise de variância e as médias comparadas pelo teste t (LSD) ao nível de 5 % de probabilidade. A variável avaliada foi a mortalidade acumulada das lagartas. As observações foram feitas diariamente porém, para a análise estatística consideraram-se as avaliações realizadas aos 4, 6, 8, 10 e 15 dias. Os dados foram corrigidos utilizando-se a raiz quadrada de x + 1. No experimento sobre a influência da temperatura, foi verificado que quanto maior a temperatura, maior a mortalidade causadas pelo TaV e pelo B. thuringiensis, tanto para lagartas de 3o. instar quanto para lagartas de 5o. instar de T. arnobia. As temperaturas mais favoráveis para a expressão da ação de ambos os patógenos foi 26 e 30ºC. No experimento sobre o efeito do pH da calda de pulverização... .
The objective of this work was to evaluate the efficiency of Thyrinteina arnobia virus (TaV) and Bacillus thuringiensis when exposed to different conditions of pH and temperature to the eucalyptus brown looper control Thyrinteina arnobia (Stoll, 1782) (Lepidoptera: Geometridae). It was evaluated at 4 different temperatures (18, 22, 26 and 30ºC) and 4 different pHs (5, 6, 7 and 8). T. arnobia larvae were reared in an artificial diet and maintained in the laboratory. The entomopathogens were applied to Eucalyptus grandis leaves, and these were offered to larvae at the 3rd and 5th instars. The pH assay was conducted in a controlled conditions (temperature of 25 ± 1oC ; RH: 70 ± 10 % and photophase of 13 hours). The temperature assays were conducted at a controlled temperatures, in a BOD room with photophase of 13 hours. The experiments were installed in the following factorial analysis 4x3, with a experimental design completely randonized, with 10 replications with 5 larvae each one. The data obtained were submitted to ANOVA and means compared by t test (LSD) (P£ 0.05). The variable evaluated was the accumulative larvae death. The observations were made daily, but for the statistical analysis only the evaluations in 4, 6, 8, 10 and 15 days were considered. The temperature experiment showed that higher temperature caused higher mortality to both 3rd and 5th instars of T. arnobia larvae. The more favorable temperatures were 26ºC and 30ºC for the expression of both pathogens. The results of suspention pH experiment showed that pH 7,0 was the most adequated for the B. thuringiensis action for both instars of T. arnobia. However, the TaV action in T. arnobia larvae was not affected for the different pHs evaluated. In different experiments carried out, 3rd instar larvae were more susceptible than to 5th instar. Also for the different temperatures and of different pHs, B. thuringiensis... (Complete abstract, click electronic address below).
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Linkous, Emily Kathryn. "Integrating biological control and chemical control of cabbage caterpillar pests." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366362436.
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Irby, Nate. "Discolorations in Southern hardwood logs biological and non-biological staining control practices /." Master's thesis, Mississippi State : Mississippi State University, 2008. http://library.msstate.edu/etd/show.asp?etd=etd-03182008-103654.
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Fabrini, Giulia. "Numerical methods for optimal control problems with biological applications." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066096/document.
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Cette thèse se développe sur deux fronts: nous nous concentrons sur les méthodes numériques des problèmes de contrôle optimal, en particulier sur le Principe de la Programmation Dynamique et sur le Model Predictive Control (MPC) et nous présentons des applications de techniques de contrôle en biologie. Dans la première partie, nous considérons l'approximation d'un problème de contrôle optimal avec horizon infini, qui combine une première étape, basée sur MPC permettant d'obtenir rapidement une bonne approximation de la trajectoire optimal, et une seconde étape, dans la quelle l¿équation de Bellman est résolue dans un voisinage de la trajectoire de référence. De cette façon, on peux réduire une grande partie de la taille du domaine dans lequel on résout l¿équation de Bellman et diminuer la complexité du calcul. Le deuxième sujet est le contrôle des méthodes Level Set: on considère un problème de contrôle optimal, dans lequel la dynamique est donnée par la propagation d'un graphe à une dimension, contrôlé par la vitesse normale. Un état finale est fixé, l'objectif étant de le rejoindre en minimisant une fonction coût appropriée. On utilise la programmation dynamique grâce à une réduction d'ordre de l'équation utilisant la Proper Orthogonal Decomposition. La deuxième partie est dédiée à l'application des méthodes de contrôle en biologie. On présente un modèle décrit par une équation aux dérivées partielles qui modélise l'évolution d'une population de cellules tumorales. On analyse les caractéristiques du modèle et on formule et résout numériquement un problème de contrôle optimal concernant ce modèle, où le contrôle représente la quantité du médicament administréeThis thesis is divided in two parts: in the first part we focus on numerical methods for optimal control problems, in particular on the Dynamic Programming Principle and on Model Predictive Control (MPC), in the second part we present some applications of the control techniques in biology. In the first part of the thesis, we consider the approximation of an optimal control problem with an infinite horizon, which combines a first step based on MPC, to obtain a fast but rough approximation of the optimal trajectory and a second step where we solve the Bellman equation in a neighborhood of the reference trajectory. In this way, we can reduce the size of the domain in which the Bellman equation can be solved and so the computational complexity is reduced as well. The second topic of this thesis is the control of the Level Set methods: we consider an optimal control, in which the dynamics is given by the propagation of a one dimensional graph, which is controlled by the normal velocity. A final state is fixed and the aim is to reach the trajectory chosen as a target minimizing an appropriate cost functional. To apply the Dynamic Programming approach we firstly reduce the size of the system using the Proper Orthogonal Decomposition. The second part of the thesis is devoted to the application of control methods in biology. We present a model described by a partial differential equation that models the evolution of a population of tumor cells. We analyze the mathematical and biological features of the model. Then we formulate an optimal control problem for this model and we solve it numerically
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Lutz, Matthias Peter. "Towards the biological control of mycotoxigenic fungi /." [Zürich], 2004. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=15738.
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Molta, N. B. "Biological control of mosquitoes with rhabditoid nematodes." Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/8901.
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Cheah, Carole A. S. J. "Biological control of the chrysanthemum leaf-miner." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254067.
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Rutherford, Michael Andrew. "Biological control of Rhizoctonia solani on potatoes." Thesis, Queen's University Belfast, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336000.
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Clarkson, John Paul. "Biological control of eyespot disease of cereals." Thesis, University of Nottingham, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336191.
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Swadling, Iain. "Biological control of Botrytis cinerea in strawberries." Thesis, University of Kent, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240120.
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Paterson, Iain Douglas. "Biological control of Pereskia aculeata Miller (Cactaceae)." Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1007653.
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Pereskia aculeata Miller (Cactaceae) is an environmental weed that is damaging to natural ecosystems in South Africa. The plant is native to Central and South America and was first recorded in South Africa in a botanical garden in 1858. In this thesis, research into the biological control of P. aculeata was conducted with the intention of improving the control of the weed. A pre-release study of the relationship between P. aculeata density and native plant biodiversity indicated that P. aculeata has a negative impact on native biodiversity. The native plant biodiversity associated with different P. aculeata densities was used to determine threshold values and goals for the control of the weed. A threshold value of 50% P. aculeata density was calculated, indicating that P. aculeata density must be maintained below 50% in order to conserve native plant biodiversity. The ultimate goal of the control programme should be to maintain P. aculeata densities below 30%. At these densities there was no significant difference in native plant biodiversity from if the weed were absent from the ecosystem. The biological control agent, Phenrica guérini Bechyne (Chrysomelidae), has been released in South Africa but the potential of the agent to impact P. aculeata is not known and no post release evaluation has been conducted. Impact assessment studies indicate that P. guérini does not impact P. aculeata, even at high densities, but the results of greenhouse experiments should be interpreted with caution because of problems with extrapolation into the field. Although observations in the field suggest that P. guérini has reduced P. aculeata densities at one site, it is clear that new biological control agents are needed to reduce the weed to acceptable levels. Identifying the origin of the South African P. aculeata population was believed to be important to the biological control programme due to the disjunct native distribution and intraspecific variation of the species. Natural enemies associated with plant genotypes in different parts of the native distribution may have developed specialised relationships with certain intraspecific variants of the plant, resulting in differences in agent efficacy on certain host plant genotypes. A molecular study indicated that the closest relatives to the South African weed population found in the native distribution were in Rio de Janeiro Province, Brazil. A bioassay experiment in which fitness related traits of the biological control agent, P. guérini, were measured on various P. aculeata genotypes was conducted to determine the importance of host plant intraspecific variation. There was little variation in fitness traits between genotypes and no evidence of intraspecific host plant specialization. Although intraspecific variation had no effect on agent efficacy in the case of P. guérini, it is possible that other natural enemies may be more specialized. Genotype matching is expected to be more important when natural enemies likely to be specialised to individual genotypes are considered for biological control. Potential biological control agents were prioritized from data collected on surveys in the native distribution. The most promising of these, based on the presence of feeding, incidence, predicted host range, climatic matching, genotype matching and mode of damage, are two species of Curculionidae, the current biological control agent P. guérini and the stem boring moth, Maracayia chiorisalis Walker (Crambidae). The two curculionid species and M. chlorisalis should be considered priorities for host specificity studies. Releases of P. guérini and any new biological control agents should be made at sites where the pre-release study was conducted so that post-release evaluation data can be compared with the pre-release data and the impact of biological control can be evaluated. Retrospective analyses of biological control programmes provide important ways of improving aspects of biological control programmes, such as methods of agent selection. The evaluation of success in biological control programmes is essential for retrospective analyses because factors that have lead to successes or failures can be analysed. Retrospective analyses of biological control programmes, such as this thesis, may improve weed management, thereby contributing to the conservation of natural resources.
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Cowman, Tyler. "Compression and Version Control of Biological Networks." Case Western Reserve University School of Graduate Studies / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=case160701146645758.
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Rodrigues, Camila Alves [UNESP]. "Eficiência de predação de Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) sobre o tripes do amendoim Enneothrips flavens (Moulton, 1941) (Thysanoptera: Thripidae)." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/91351.
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Este estudo teve como objetivo verificar o potencial de predação de E. flavens através da liberação de ovos embrionados e larvas de primeiro ínstar de C. externa em plantas de amendoim cultivadas em casa-de-vegetação. O delineamento experimental utilizado foi o inteiramente casualizado com três tratamentos (plantas que não receberam liberação, plantas que receberam liberação de ovos embrionados e plantas que receberam liberação de larvas de primeiro ínstar) e 15 repetições no primeiro experimento e 20 no segundo. Foram realizadas amostragens antes da liberação e com 4, 9 e 15 dias após. No primeiro experimento e em relação às diferentes amostragens, as plantas que não receberam liberação o número médio de tripes não variou significativamente. As plantas que receberam liberação de ovos e larvas apresentaram aumento significativo do número médio de tripes aos quatro dias. Aos nove dias o número médio de tripes reduziu-se significativamente nas plantas que receberam liberação de ovos e aos 15 dias nas plantas que receberam liberação de larvas. No segundo experimento e em relação às diferentes amostragens, o número médio de tripes nas plantas que não receberam liberação não variou significativamente, como ocorrido no primeiro experimento. As plantas que receberam liberação de ovos apresentaram redução significativa no número médio de tripes aos quatro dias após a liberação. O mesmo ocorreu com as plantas que receberam liberação de larvas. Foi observado no segundo experimento, através da fórmula de Abbott, eficiência de redução da população de tripes de 71 e 74%, quando foram liberados ovos e larvas, respectivamente. Dessa maneira foi possível verificar que C. externa possui potencial de predação sobre o tripes do amendoim E. flavens
This study was carried out in order to verify the potential of predation of E. flavens through the release of fertilized eggs and first instar larvae of C. externa peanut plants grown in a greenhouse. The experimental design was completely randomized design with three treatments (plants that did not receive release, plants that received release embryonated eggs and plants that received release of the first larval instar) and 15 repetitions in the first experiment and 20 in the second. Samplings were made before the release and with 4, 9 and 15 days. In the first experiment and for the different samples, plants that were not release the average number of thrips did not vary significantly. The plants that received the release of eggs and larvae showed significant increase in the average number of thrips to four days. At nine days the average number of thrips decreased significantly in plants that received release of eggs and 15 days in plants that received release of larvae. In the second experiment and for the different samples, the average number of thrips on plants that did not receive release did not vary significantly, as occurred in the first experiment. The plants that received the release of eggs showed a significant reduction in the average number of thrips to four days after release. The same occurred with the plants that received release of larvae. Was observed in the second experiment, using the formula of Abbott, efficiency of reducing the population of thrips on 71 and 74%, when they were released eggs and larvae, respectively. Thus we observed that C. has the potential external predation on thrips in peanut E. flavens
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Garcia, Luiz Cláudio [UNESP]. "Interferência da pressurização da calda de pulverização sobre microrganismos entomopatogênicos." Universidade Estadual Paulista (UNESP), 2003. http://hdl.handle.net/11449/97205.
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garcia_lc_me_botfca.pdf: 627408 bytes, checksum: 6e8090157ad35eb0a16ecfae89cd91f4 (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A tecnologia de aplicação desenvolvida para produtos químicos têm sido utilizada para organismos entomopatogênicos sem o estudo prévio das necessidades de adaptações que visem a manutenção da viabilidade desses agentes de controle biológico. O experimento teve por objetivo avaliar a influência da pressurização e despressurização da calda de pulverização na viabilidade dos seguintes microrganismos entomopatogênicos: Metarhizium anisopliae, Bacillus thuringiensis, AgMNPV e Steinernema glaseri. Foi utilizado o sistema hidráulico de um pulverizador, sem filtros, equipado com ponta de pulverização de jato cônico JA-2, com 15 minutos de agitação da calda antes da coleta. O delineamento experimental utilizado foi o inteiramente casualizado, com sete tratamentos: pressurização da calda em zero; 175,8; 351,6; 527,4; 703,2; 1.054,9; 1.406,5 kPa (zero, 25, 50, 75, 100, 150 e 200 lbf.pol-2). A avaliação da viabilidade de M. anisopliae se deu através da porcentagem de conídios germinados. Para B. thuringiensis foi considerado o número de colônias formadas. A eficácia do AgMNPV foi estimada indiretamente, pela mortalidade causada às lagartas de Anticarsia gemmatalis no início do terceiro ínstar, alimentadas com dieta artificial impregnada com a suspensão viral. No experimento com o S. glaseri foi calculada a porcentagem de indivíduos vivos, determinada através de microscopia óptica, em lâmina de peters. Conclui-se que se pode pulverizar os entomopatógenos M. anisopliae, B. thuringiensis, AgMNPV e S. glaseri, até a pressão de 1.406,5 kPa, sem que haja perda na viabilidade desses organismos utilizados como agentes de controle biológico.
Application technology developed to chemical products has been employed for entomopathogenic organisms without the previous studies on the necessities of adaptations aiming at viability maintenance of these biological control agents. The objective of the research was to evaluate the influence of pressurization and decompression of spraying suspension in the viability of the following entomopathogenic microorganisms: Metarhizium anisopliae, Bacillus thuringiensis, AgMNPV and Steinernema glaseri. The sprayer hydraulical system was used without filters and equipped with JA-2 hollow-cone nozzle type with 15 minutes of spray agitation before it collects. The experimental design was completely randomized, with seven treatments: pressurization of spraying suspension at 0.0; 175.8; 351.6; 527.4; 703.2; 1,054.9 and 1,406.5 kPa. Evaluation of the viability of M. anisopliae was estimated by the percentage of conidia germinated. For B. thuringiensis, the number of colonies formed. Efficiency on AgMNPV was estimated indirectly, by means of mortality caused to velvet bean caterpillar (Anticarsia gemmatalis) in early third ínstar; the specimens were fed with artificial diet impregnated with viral suspension. For the experiment with the S. glaseri it was calculated the percentage of live specimens; observation were performed through optic microscopy, on Peters slide-blade. It was concluded that the entomopathogens M. anisopliae, B. thuringiensis, AgMNPV and S. glaseri can be sprayed up to the pressure of 1,406.5 kPa without loss in the viability of those organisms as agents of biological control.
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Colmenarez, Yelitza Coromoto 1974. "Virulência de Thyrinteina arnobia virus (TaV) e de Bacillus thuringiensis à Thyrinteina arnobia (Lepidoptera: Geometridae) : efeito da temperatura no desenvolvimento das lagartas e do pH da calda de pulverização /." Botucatu : [s.n.], 2003. http://hdl.handle.net/11449/97243.
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Orientador: Carlos Frederico WilckenResumo: Este estudo teve por objetivo avaliar a eficiência do Thyrinteina arnobia vírus (TaV) e de Bacillus thuringiensis quando submetidos a diferentes condições de pH e temperatura no controle da lagarta parda Thyrinteina arnobia (Stoll, 1782) (Lepidoptera: Geometridae). Foram testadas 4 temperaturas (18, 22, 26 e 30º C) e 4 pHs diferentes (5, 6, 7 e 8). Os ovos de Thyrinteina arnobia foram provenientes de uma criação em dieta artificial, mantida em laboratório. Os entomopatógenos foram aplicados em folhas de Eucalyptus grandis, para posterior oferecimento à lagartas do 3º. e 5º. instares. O ensaio de pH foi conduzido em sala climatizada (temperatura: 25 ± 1oC ; UR: 70 ± 10 % e fotofase de 13 horas), enquanto que os ensaios de temperatura os tratamentos foram conduzidos em câmaras de BOD e fotofase de 13 horas. Os experimentos foram instalados no delineamento experimental inteiramente casualizado e a distribuição dos tratamentosem esquema fatorial 4x3, com 10 repetições de 5 lagartas cada uma, sendo avaliadas 150 lagartas para cada tratamento. Os dados obtidos foram submetidos à análise de variância e as médias comparadas pelo teste t (LSD) ao nível de 5 % de probabilidade. A variável avaliada foi a mortalidade acumulada das lagartas. As observações foram feitas diariamente porém, para a análise estatística consideraram-se as avaliações realizadas aos 4, 6, 8, 10 e 15 dias. Os dados foram corrigidos utilizando-se a raiz quadrada de x + 1. No experimento sobre a influência da temperatura, foi verificado que quanto maior a temperatura, maior a mortalidade causadas pelo TaV e pelo B. thuringiensis, tanto para lagartas de 3o. instar quanto para lagartas de 5o. instar de T. arnobia. As temperaturas mais favoráveis para a expressão da ação de ambos os patógenos foi 26 e 30ºC. No experimento sobre o efeito do pH da calda de pulverização... (Resumo completo, clicar acesso eletrônico abaixo).
Abstract: The objective of this work was to evaluate the efficiency of Thyrinteina arnobia virus (TaV) and Bacillus thuringiensis when exposed to different conditions of pH and temperature to the eucalyptus brown looper control Thyrinteina arnobia (Stoll, 1782) (Lepidoptera: Geometridae). It was evaluated at 4 different temperatures (18, 22, 26 and 30ºC) and 4 different pHs (5, 6, 7 and 8). T. arnobia larvae were reared in an artificial diet and maintained in the laboratory. The entomopathogens were applied to Eucalyptus grandis leaves, and these were offered to larvae at the 3rd and 5th instars. The pH assay was conducted in a controlled conditions (temperature of 25 ± 1oC ; RH: 70 ± 10 % and photophase of 13 hours). The temperature assays were conducted at a controlled temperatures, in a BOD room with photophase of 13 hours. The experiments were installed in the following factorial analysis 4x3, with a experimental design completely randonized, with 10 replications with 5 larvae each one. The data obtained were submitted to ANOVA and means compared by t test (LSD) (P£ 0.05). The variable evaluated was the accumulative larvae death. The observations were made daily, but for the statistical analysis only the evaluations in 4, 6, 8, 10 and 15 days were considered. The temperature experiment showed that higher temperature caused higher mortality to both 3rd and 5th instars of T. arnobia larvae. The more favorable temperatures were 26ºC and 30ºC for the expression of both pathogens. The results of suspention pH experiment showed that pH 7,0 was the most adequated for the B. thuringiensis action for both instars of T. arnobia. However, the TaV action in T. arnobia larvae was not affected for the different pHs evaluated. In different experiments carried out, 3rd instar larvae were more susceptible than to 5th instar. Also for the different temperatures and of different pHs, B. thuringiensis... (Complete abstract, click electronic address below).
Mestre
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Dieterich, Mabin Molly E. "Effects of conservation biological control practices on predatory arthropod assemblages and molecular identification of cucumber beetle biological control agents." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492531428052099.
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Zhang, Wenming. "Biological control of Echinochloa species with pathogenic fungi." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40293.
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Six pathogenic fungal species were isolated from naturally-infected Echinochloa species and evaluated as biological control agents for E. crus-galli, E. colona, and E. glabrescens in rice. Bipolaris sacchari, Curvularia geniculata, and Exserohilum monoceras were non-pathogenic to rice and caused high mortality of Echinochloa species. E. monoceras was selected for further study. Under regulated greenhouse conditions, an inoculum dose of 2.5 $ times$ 10$ sp7$ conidia/m$ sp2$ killed E. crus-galli and E. glabrescens seedlings while 5.0 $ times$ 10$ sp7$ conidia/m$ sp2$ caused 100% mortality of E. colona seedlings. The 1.5-leaf stage was the most susceptible growth stage for all three Echinochloa species. E. glabrescens was most susceptible to E. monoceras infection, E. crus-galli had an intermediate susceptibility, and E. colona was least susceptible. The optimum temperature for 100% mortality was between 20 and 30 C for all Echinochloa species, whereas the minimum dew period for 100% mortality was 16 h for E. colona, 12 h for E. crus-galli, and 8 h for E. glabrescens. Under screenhouse conditions and in the absence of an artificial dew period, over 90% of Echinochloa seedlings were killed when inoculum was sprayed in an oil emulsion or when applied as a dry powder to the water surface of a simulated paddy field. Maximum conidia production occurred on V-8 juice agar or centrifuged V-8 juice agar, at 28 C in the dark. No conidia were produced in liquid media. Of various agricultural products tested as solid substrates, the highest sporulation (1.81 $ times$ 10$ sp6$ conidia/g dry weight) occurred on corn leaves. Host range tests on 54 plant species in 43 genera and 19 families showed that Rottboellia cochinchinensis, was also highly susceptible to this fungus. Of the crops tested, only corn seedlings were lightly infected under optimum greenhouse conditions but no disease occurred on corn under field conditions. Bipolaris sacchari, Exserohilum monoceras, and E. oryzae
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Muniz, Elen Regozino. "Termotolerância de Metarhizium spp. e efeito de sua formulação sobre a virulência para Rhipicephalus microplus expostos à condições estressantes de temperatura e umidade." Universidade Federal de Goiás, 2015. http://repositorio.bc.ufg.br/tede/handle/tede/4898.
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Rhipicephalus microplus, known as tick of the cattle, cause great economic losses each year in Brazil. Entomopathogenic fungi stand out as an alternative to the exclusive control and indiscriminate use of the chemical. However, ambient temperature above the threshold considered optimal for these organisms can interfere with your biology, and compromise their development and effectiveness. In the present study evaluated biological parameters seven strains of Metarhizium spp. (IP1, IP34, IP46, IP60, IP119, IP125 and IP146) originated from the Central Brazil, incubated at 32 ± 0.5°C or 27 ± 1°C. In addition, the virulence was assessed for each strain of R. microplus engorged females. IP119, Metarhizium anisopliae s.s., was selected among the other isolates for virulence tests against R. microplus submitted with stressful temperature condition (32 ± 0.5°C) or low relative humidity (RH = 75%) to present considerable heat tolerance and virulence in the screening tests. Tests with conidia formulated in oil-water emulsion (liquid vaseline 5%), carboxymethylcellulose gel or emulgel 5% were conducted to evaluate the conidial thermotolerance when exposed to 45°C for 4 hours or 6 hours, and to test the efficacy of formulated to control engorged female R. microplus the stressful conditions of temperature (32°C) and low humidity (RH = 75%). It was concluded that a constant temperature of 32°C or exposure for a few hours at 45°C is stressful condition for the isolates. The conidia IP119 when bathed in liquid vaseline jelly were more tolerant of exposure to 45°C for 4 hours. IP119 was shown to be virulent for engorged female R. microplus, being the oil-water emulsion 5% of the most effective formulation.
Rhipicephalus microplus, conhecido como carrapato-dos-bovinos, causa grandes percas econômicas por ano no Brasil. Fungos entomopatogênicos se destacam como controle alternativo ao uso exclusivo e indiscriminado do químico. Contudo, a temperatura ambiente acima do limiar considerado ótimo para estes organismos pode interferir na sua biologia, e comprometer seu desenvolvimento e eficácia. No presente estudo foram avaliados parâmetros biológicos de sete linhagens de Metarhizium spp. (IP1, IP34, IP46, IP60, IP119, IP125 e IP146), originados do cerrado do Centro-Oeste brasileiro, incubados a 32±0,5°C ou 27±1°C. Além disso, foi avaliada a virulência de cada linhagem para fêmeas ingurgitadas de R. microplus. Metarhizium anisopliae s.s., IP119, foi selecionado dentre os demais isolados para os testes de virulência contra R. microplus submetidos a com condição de temperatura estressante (32±0,5°C) ou em baixa umidade relativa (UR=75%) por apresentar notável tolerância ao calor e virulência nos testes de triagem. Testes com os conídios formulados em emulsão óleo-água (vaselina líquida 5%), gel carboximetilcelulose ou emulgel 5% foram realizados para avaliar a termotolerância dos conídios quando expostos a 45°C por 4 ou 6 horas, e testar a eficácia dos formulados para o controle de fêmeas ingurgitadas de R. microplus nas condições estressantes de temperatura (32°C) e umidade baixa (UR=75%). Concluiu-se que a constante temperatura de 32°C ou a exposição por poucas horas a 45°C foi condição estressante para os isolados estudados. Os conídios de M. anisopliae s.s. (IP119) quando banhados em emulsão óleo-água 5% foram mais tolerantes em exposição a 45°C por 4 horas. M. anisopliae s.s. (IP119) mostrou ser virulento para fêmeas ingurgitadas de R. microplus, tendo sido a emulsão óleo-água 5% a formulação mais eficaz.
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Léger, Christian. "Development of a Colletotrichum dematium as a bioherbicide for the control of fireweed." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq29737.pdf.
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Govender, Veloshinie. "Evaluation of biological control systems for control of mango post-harvest diseases." Pretoria : [s.n.], 2004. http://upetd.up.ac.za/thesis/available/etd-02102006-160747.
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Mukherjee, Gaurab. "The control of seedborne diseases of Linum usitatissimum by biological control agents." Thesis, Queen's University Belfast, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284390.
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Moore, Gareth Ryan. "The role of nutrients in the biological control of water lettuce, Pistia stratiotes lamarck (Araceae) by the leaf-feeding weevil, Neohydronomus affinis Hustache (Coleoptera: Curculionidae) with particular reference to eutrophic conditions." Thesis, Rhodes University, 2006. http://hdl.handle.net/10962/d1005447.
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Water lettuce, Pistia stratiotes Lamarck (Araceae) is a South American plant that has the potential to be a very damaging and important aquatic weed in many tropical countries, including South Africa. It has the potential to rapidly multiply vegetatively and completely cover watercourses in a very short space of time outside of its natural range under ideal conditions and without its natural enemies. In such instances, the weed may cause hindrances to water transport and fishing, increasing chances of malaria, as well as affecting the natural ecology of the system. Water lettuce can also set seed, which may lay dormant for long periods, germinating when conditions are favourable. It is therefore very necessary to adopt control methods against the weed where it is a problem. However, water lettuce has also been effectively and completely controlled in many countries by the leaf-feeding weevil, Neohydronomus affinis Hustache. High nutrient levels in the form of nitrates and phosphates have been shown to have largely negative effects on biological control in several studies, with control being incomplete or taking longer than in similar areas with lower nutrient levels. The effectiveness of N. affinis on the biological control of water lettuce was investigated in a laboratory study, growing P. stratiotes plants with and without insects at different nutrient concentrations. In these studies biological control of water lettuce with N. affinis was found to be complete under eutrophic nutrient conditions, although control took longer when higher nutrient levels were tested. A field site study was conducted at a sewage settlement pond in Cape Recife Nature Reserve near Port Elizabeth, South Africa. This highly eutrophic system was used as a field example for the effectiveness of biocontrol of P. stratiotes by N. affinis under eutrophic conditions. The weevils at Cape Recife caused a massive and rapid crash in the percentage coverage of the weed, from 100% in May 2003, to approximately 0.5 % in September 2003. Plant growth parameters were also found to decrease considerably in size correspondingly with this crash from May 2003 until spring 2003. Plant size only again started to increase gradually but steadily through spring 2003 and into summer. In the laboratory studies, the fecundity of weevils was shown to be much higher on plants grown under higher nutrient concentrations than on plants grown in lower nutrient concentrations. The results from the wing-muscle analysis under different nutrient concentrations were not easy to interpret, and there were few differences in wing muscle state between most of the concentrations. From these findings it is suggested that nutrient concentration, particularly high levels of nitrates and phosphates is not a limiting factor in terms of effective biological control of P. stratiotes with N. affinis, but that under high nutrient conditions biological control might take longer.
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Mendi, Ebrahim M. "Biological control of Chenopodium album by Ascichyta caulina." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2001. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=59743.
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Grinyer, Jasmine. "Proteomic analysis of the biological control fungus Trichoderma." Doctoral thesis, Australia : Macquarie University, 2007. http://hdl.handle.net/1959.14/12407.
Full textAbstract:
Thesis by publication."August 2006"
Thesis (PhD)--Macquarie University, Division of Environmental & Life Sciences, Dept. of Biological Sciences & Dept. of Chemistry & Biomolecular Sciences), 2007.
Bibliography: leaves 157-183.
1. Introduction -- 1.1. Proteomics and two-dimensional electrophoresis -- 1.2. A proteomic approach to study the filamentous fungus Trichoderma -- 1.3. Aims of the thesis -- 2. Materials and methods -- 3. Results and discussion -- 3.1. Method development for the display and identification of fungal proteins by 2DE and mass spectrometry -- 3.2. Discovery of novel determinants in the biological control of phytopathogens by Trichoderma atroviride -- 3.3. Summary and concluding remarks.
Trichoderma harzianum and T. atroviride are filamentous fungi commonly found in soil. Both display biocontrol capabilities against a range of phytopathogenic fungi including Rhizoctonia solani and Botrytis cinerea which are known pests of hundreds of commercially important crops including tomatoes, potatoes, beans, cucumber, strawberries, cotton and grapes. These Trichoderma species secrete a combination of enzymes degrading cell walls and antibiotics to overgrow and kill fungal phytopathogens. They are seen as an environmentally friendly alternative to chemical fungicides currengly used on crops.
A proteomic approach was taken to separate and identify proteins from a strain of T. harzianum with well established biocontrol properties. Several methods were developed in this thesis to display the whole proteome content and several subcellular proteome fractions from T. harzianum. Proteins were separated by two-dimensional electrophoresis and identified by mass spectrometric methods. The resulting proteomic maps represent the first extensive array of cellular and sub-cellular proteomes for T. harzianum.
Cellular protein patterns of T. atroviride (T. harzianum P1) grown on media containing either glucose or R. solani cell walls were compared by differential gel electrophoresis to identify a suite of new proteins involved in the biological control response. Twenty four T. atroviride protein spots up-regulated in the presence of the R. solani cell walls were identified by mass spectrometry and N-terminal sequencing. Proteins identified from this study included previously implicated enzymes degrading cell walls and three novel proteases, vacuolar serine protease, vacuolar protease A and trypsin-like protease. The genes encoding two of these proteases, vacuolar protease A and vacuolar serine protease have been cloned by degenerate primer PCR and genomic walking PCR and sequenced. The gene sequences and protein sequences derived from these genes have been partially characterised.
Mode of access: World Wide Web.
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Brown, Wayne A. "Real-time control strategies for cyclical biological reactors." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0023/NQ50121.pdf.
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Batchelor, Timothy Peter. "Parasitoid interactions in behavioural ecology and biological control." Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/11176/.
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This thesis presents laboratory investigations on the competitive interactions which take place within and between bethylid parasitoids. Part one investigates the compatibility of three bethylids (Cephalonomia hyalinipennis, Cephalononlia stephanoderis and Prorops nasuta) for biocontrol releases against the principal pest of coffee, the coffee berry borer (CBB), Hypothenemus hampei. Cephalonomia hyalinipennis is able to hyperparasitise and consume pupae of C stephanoderis and P. nasuta. Cephalonomia stephanoderis also engages in intra-guild predation, consuming pupae of C hyalinipennis. In contests for CBB hosts, fatal fighting occurs in 69% of inter-specific replicates but never occurs in intra-specific replicates. This suggests that interspecific competition is stronger than intraspecific competition and that species coexistence may be compromised. Cephalonomia tephanoderis is the superior interspecific contestant while P. nasuta is the least successful and never kills an opponent. Where CBB infested coffee berries are provided to the three bethylids, coexistence between species is possible, but rare, within a single coffee berry. Prorops nasuta is the most successful species in interspecific replicates and replicates containing C. hyalinipennis generally have low production, regardless of the species combination added. Part two investigates contest interactions, the variables that influence contest outcome between Goniozus nephantidis females and chemical release. Prior ownership and difference in contestant weight have positive influences on contest outcome. Host weight positively influences the outcome of contests between two 'owners' and 'intruder' take-over success increases when intruders are older than owners. Seven bethylid species are found to release volatile chemicals when stressed. A pilot study identifies the volatile chemical in G. nephantidis and employs Atmospheric Pressure Chemical Ionisation-Mass Spectrometry for real-time analysis of chemical release during contest interactions. The appendix contains an advanced investigation using this technique. Bethylids are useful model organisms for the study of competitive interactions but appear to be generally ineffective as biological control agents.
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Kearns, Leah. "Biological control of Erwinia amylovora by Erwinia herbicola." Thesis, University of Canterbury. Microbiology, 1993. http://hdl.handle.net/10092/6801.
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A naturally-occurring Erwinia herbicola strain, Eh1087, inhibitory to Erwinia amylovora (Burr.) Winslow et al. (1920) was isolated from apple blossom (Malus X. domestica Borkh.) in a Canterbury orchard. Total populations of E. herbicola on apple blossoms in Canterbury and Hawkes Bay orchards were low (less than 50 cfu.blossom-1) throughout flowering, increasing l00-fold at petal drop. E. Herbicola populations at petal drop were more dominant in Canterbury orchards (30-50% of total) than in Hawkes Bay orchards (1-2% of total) in the seasons surveyed. In vitro inhibition of E. amylovora was observed for 20% of all bacterial strains isolated from Canterbury orchards and from none of the strains isolated from Hawkes Bay orchards under the conditions used.
Eh1087 established stable populations for at least 10 days post application when sprayed onto apple blossoms in the orchard. This strain produced a broad spectrum, non-peptide, β-lactam antibiotic in vitro that was bactericidal for E. amylovora. Eh1087 suppressed E. amylovora disease symptoms in immature pear fruit, excised apple shoots and in apple blossoms. The partially purified antibiotic of Eh1087 reduced the severity of symptom expression in immature pear fruit.
TnphoA-insertion mutants of Eh1087 were created (Ant-) that failed to inhibit E. amylovora in vitro and in immature pear fruit. Ant- mutants no longer produced an antibiotic inhibitory to E. amylovora in vitro. TnphoA insertions in the Ant- mutants all mapped within a 1.5 kb region on a 200 kb indigenous plasmid of Ehl087.
A genomic library of Eh1087 was constructed and cosmids which complemented Ant- mutants to the Ant+ phenotype in vitro and in immature pear fruit were selected.
A HinIII 8 kb cosmid fragment subclone, pAH8, weakly complemented Ant- mutant EhA17g. This complementation was enhanced by the presence in trans of an EcoR1 5 kb cosmid fragment subclone, pBE5B, which mapped approximately 6 kb away from the region of TnphoA insertions.
Analysis of the proteins produced by these cosmid fragment sub clones in Escherichia coli mini-cells revealed that pBE5B codes for three proteins, approximately 20, 34 and 41 kd in size and pAH8 codes for two proteins, approximately 28 and 39 kd in size. At least one of the proteins coded for by pAH8 must be essential to antibiotic synthesis in Eh1087. The possible relationship between the cosmid fragment-encoded proteins and b-lactam biosynthetic enzymes is discussed.
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Khidr, Sahand Kamal. "Biology and biological control potential of bethylid wasps." Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/28813/.
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This thesis presents a series of experiments on the evolutionary ecology of the reproduction, behaviour, chemical and molecular characteristics of bethylid wasps in the genus Goniozus. Part One investigates host quality by varying host age after paralysis. The quality of paralyzed hosts declines with time since paralysis negatively influences life-history characteristics of Goniozus nephantidis. Assessment of host metabolomic profiles show which chemicals change as hosts age. Part Two investigates the effect of kin recognition on contest behaviour among adult females ofGoniozus legneri. Competitive behaviour was thus used to study the basis of kin recognition mechanisms. Wasps that are genetic kin and wasps that are reared on the same host behave less aggressively towards each other than do non-kin and nonhostmates. It is likely that cuticular hydrocarbon profiles are used by wasps in kin recognition. The environmental and genetic influences on wasp cuticular hydrocarbon profiles were explored: chemical composition differed according to both wasp species and host species. Part Three investigates genetic characteristics of Goniozus legneri populations on kin recognition behaviour. A molecular genetic marker system was developed for Goniozus species. Microsatellites showed clear polymorphism in six primer pairs and are likely to be a valuable tool in the future for closely related species. One of these markers was utilized to assess sex allocation at oviposition, thus avoiding potentially biasing influences of developmental mortality. Developmental mortality does not differ between the sexes but mortality increased, sex ratio variance across offspring groups and can obscure relationships between sexual composition andg roup size that are present at oviposition. A tendency for Goniozus legneri to lay male and female eggs in spatial separation was also observed. Although the focus of these studies is on fundamental aspects of bethylid biology, advances in all of these areas have potential to enhance the deployment of these parasitoids in biological pest control.
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Dando, Malcolm R. "The New Biological Weapons: Threat, Proliferation, and Control." Lynne Rienner Publishers, 2001. http://hdl.handle.net/10454/3933.
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Current revolutions in biotechnology and neuroscience are changing military technologies, necessitating dramatic re-evaluations in arms regulatory regimes. This study assesses how these new technologies can be used in weapons systems - by governments and terrorists alike - and whether this frightening development can be brought under effective international control. Malcolm Dando begins by surveying the existing (and arguably inadequate) control mechanisms for chemical and biological weapons. He then discusses how earlier generations of toxin and bioregulatory weapons have been used by such states as Iraq, the Soviet Union and the USA, and explains, in non-technical terms, the implications for new weapons technology. Considering how international law might be applied to constrain undesirable military developments without restricting technological developments for peaceful purposes, Dando concludes with a proposal for an integrated control regime that would link international agreements, national legislation, and trade regulations.
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Holliday, Gillian. "Biological control of seed-borne bacterial plant pathogens." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309601.
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Rind, Bashiran. "Studies relating to biological control of Armillaria mellea." Thesis, University of Sheffield, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369944.
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Crozier, Jayne. "Biological control of wood decay in tropical hardwoods." Thesis, Manchester Metropolitan University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367732.
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Manyonge, Lawrence. "Autonomous finite capacity scheduling using biological control principles." Thesis, De Montfort University, 2012. http://hdl.handle.net/2086/7986.
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The vast majority of the research efforts in finite capacity scheduling over the past several years has focused on the generation of precise and almost exact measures for the working schedule presupposing complete information and a deterministic environment. During execution, however, production may be the subject of considerable variability, which may lead to frequent schedule interruptions. Production scheduling mechanisms are developed based on centralised control architecture in which all of the knowledge base and databases are modelled at the same location. This control architecture has difficulty in handling complex manufacturing systems that require knowledge and data at different locations. Adopting biological control principles refers to the process where a schedule is developed prior to the start of the processing after considering all the parameters involved at a resource involved and updated accordingly as the process executes. This research reviews the best practices in gene transcription and translation control methods and adopts these principles in the development of an autonomous finite capacity scheduling control logic aimed at reducing excessive use of manual input in planning tasks. With autonomous decision-making functionality, finite capacity scheduling will as much as practicably possible be able to respond autonomously to schedule disruptions by deployment of proactive scheduling procedures that may be used to revise or re-optimize the schedule when unexpected events occur. The novelty of this work is the ability of production resources to autonomously take decisions and the same way decisions are taken by autonomous entities in the process of gene transcription and translation. The idea has been implemented by the integration of simulation and modelling techniques with Taguchi analysis to investigate the contributions of finite capacity scheduling factors, and determination of the ‘what if’ scenarios encountered due to the existence of variability in production processes. The control logic adopts the induction rules as used in gene expression control mechanisms, studied in biological systems. Scheduling factors are identified to that effect and are investigated to find their effects on selected performance measurements for each resource in used. How they are used to deal with variability in the process is one major objective for this research as it is because of the variability that autonomous decision making becomes of interest. Although different scheduling techniques have been applied and are successful in production planning and control, the results obtained from the inclusion of the autonomous finite capacity scheduling control logic has proved that significant improvement can still be achieved.
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Wilson, Michael John. "A nematode parasite for biological control of slugs." Thesis, University of Bristol, 1992. http://hdl.handle.net/1983/531bec1a-d998-4369-abbd-47c8c69e676c.
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Gayzik, Francis Scott. "Optimal Control of Thermal Damage to Biological Materials." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/35087.
Full textAbstract:
Hyperthermia is a cancer treatment modality that raises cancerous tissue to cytotoxic temperature levels for roughly 30 to 45 minutes. Hyperthermia treatment planning refers to the
use of computational models to optimize the heating protocol to be used in a hyperthermia
treatment. This thesis presents a method to optimize a hyperthermia treatment heating
protocol. An algorithm is developed which recovers a heating protocol that will cause a
desired amount of thermal damage within a region of tissue. The optimization algorithm is
validated experimentally on an albumen tissue phantom.The transient temperature distribution within the region is simulated using a two- dimensional, finite-difference model of the Pennes bioheat equation. The relationship between temperature and time is integrated to produce a damage field according to two different models; Henriques'' model and the thermal dose model (Moritz and Henriques (1947)), (Sapareto and Dewey (1984)). A minimization algorithm is developed which re duces the value of an objective function based on the squared difference between an optimal and calculated damage field. Either damage model can be used in the minimization algorithm. The adjoint problem in conjunction with the conjugate gradient method is used to minimize the objective function of the control problem.
The flexibility of the minimization algorithm is proven experimentally and through a variety of simulations. With regards to the validation experiment, the optimal and recovered regions of permanent thermal damage are in good agreement for each test performed. A sensitivity analysis of the finite difference and damage models shows that the experimentally-obtained extent of damage is consistently within a tolerable error range.
Excellent agreement between the optimal and recovered damage fields is also found in
simulations of hyperthermia treatments on perfused tissue. A simplified and complex model
of the human skin were created for use within the algorithm. Minimizations using both the
Henriques'' model and the thermal dose model in the objective function are performed.
The Henriques'' damage model was found to be more desirable for use in the minimization algorithm than the thermal dose model because it is less computationally intensive
and includes a mechanism to predict the threshold of permanent thermal damage. The
performance of the minimization algorithm was not hindered by adding complexity to the skin
model. The method presented here for optimizing hyperthermia treatments is shown to be
robust and merits further investigation using more complicated patient models.
Master of Science