Дисертації з теми "Seedling resistance"
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Morse, Stephen. "The role of hydroxamic acids in conferring resistance to aphid pests of seedling maize (Zea mays)." Thesis, University of Southampton, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293605.
Повний текст джерелаLorentz, Andrew. "Design, construction and testing of an ascending micropenetrometer to measure soil crust resistance." Thesis, Cranfield University, 2014. http://dspace.lib.cranfield.ac.uk/handle/1826/8511.
Повний текст джерелаMalligan, Cassandra D. "Crown rot (fusarium pseudograminearum) symptom development and pathogen spread in wheat genotypes with varying disease resistance." University of Southern Queensland, Faculty of Sciences, 2009. http://eprints.usq.edu.au/archive/00006225/.
Повний текст джерелаSandhu, Karanjeet Singh. "Genetic and molecular analyses of barley for seedling and adult plant resistance against rust diseases." Thesis, The University of Sydney, 2011. http://hdl.handle.net/2123/8860.
Повний текст джерелаDugo, Tesfaye Letta <1976>. "Association mapping of stem rust resistance in durum wheat at the seedling and adult plant stages." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5935/1/Dugo_Tesfaye_tesi.pdf.
Повний текст джерелаDugo, Tesfaye Letta <1976>. "Association mapping of stem rust resistance in durum wheat at the seedling and adult plant stages." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5935/.
Повний текст джерелаPogoda, Maria [Verfasser], Jochen C. [Gutachter] Reif, and Ralph [Gutachter] Panstruga. "Identification and validation of seedling powdery mildew resistance genes / Maria Pogoda ; Gutachter: Jochen C. Reif, Ralph Panstruga." Halle (Saale) : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2019. http://d-nb.info/1210730200/34.
Повний текст джерелаEllis, Margaret Lee. "The Soybean Seedling Disease Complex: Pythium spp. and Fusarium graminearum and their Management through Host Resistance." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1322495401.
Повний текст джерелаWeerasooriya, Dilooshi Kumari. "Genetic analysis of interveinal chlorosis and reduced seedling vigor as related to agronomic performance in sorghum resistant to ALS inhibitor herbicides." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32896.
Повний текст джерелаDepartment of Agronomy
Tesfaye T. Tesso
The lack of effective post-emergence weed control options is often highlighted as one of the major factors behind dwindling acreage under sorghum (Sorghum bicolor (L.) Moench) in the United States. The discovery of herbicide resistance sources in wild sorghum population and subsequent efforts to incorporate them into cultivated sorghum was received with much optimism to change weed management practices in sorghum. As the development of the technology advances, especially of the Acetolactate synthase (ALS) resistance, concerns over the temporary interveinal chlorosis and reduced seedling vigor in some of the resistant families became heightened. This thesis research is designed to shed light on the genetic basis of seedling chlorosis and assess its impacts on yield potential. The study has three parts; the first part is focused on identifying the genetic causes and plant mechanisms associated with the chlorotic phenotype. ALS herbicide resistant sister-lines expressing normal and chlorotic phenotypes were analyzed via RNA sequencing at four time points during seedling growth. The study identified several variants of genes coding chloroplast precursors and those that cause epigenetic modifications. Once confirmed, genetic markers can be developed to track these gene variants in the breeding population and eliminate segregates genetically prone to chlorosis/yellowing. The second part of the study focuses on assessing the effect of ALS resistance associated chlorosis on agronomic and nutritional parameters of sorghum inbred lines. A set of ALS resistant lines expressing different levels of the chlorotic phenotype were evaluated in replicated field trials and laboratory methods. Results showed that interveinal chlorosis delays flowering but does not have negative effect on yield and nutritional parameters with and without herbicide treatment. The last part addresses whether there is any yield drag that may be associated with herbicide resistance traits and foliar interveinal chlorosis. For this, we synthesized a large set (182) of hybrids from ALS resistant, ACCase resistant and regular (susceptible) seed and pollinator parents. The hybrids were then evaluated in three sets at multiple locations during the 2014 and 2015 crop seasons along with commercial checks. The results revealed that resistance to both herbicides do not cause any drag to grain yield. The traits also do not have any negative impact on grain and nutritional quality of resistant hybrids.
Kalia, Bhanu. "Mining the Aegilops tauschii gene pool: evaluation, introgression and molecular characterization of adult plant resistance to leaf rust and seedling resistance to tan spot in synthetic hexaploid wheat." Diss., Kansas State University, 2015. http://hdl.handle.net/2097/18934.
Повний текст джерелаGenetics Interdepartmental Program
Bikram S. Gill
Leaf rust, caused by fungus Puccinia triticina, is an important foliar disease of wheat worldwide. Breeding for race-nonspecific resistant cultivars is the best strategy to combat this disease. Aegilops tauschii, D genome donor of hexaploid wheat, has provided resistance to several pests and pathogens of wheat. To identify potentially new adult plant resistance (APR) genes, 371 geographically diverse Ae. tauschii accessions were evaluated in field with leaf rust (LR) composite culture of predominant races. Accessions from Afghanistan only displayed APR whereas both seedling resistance and APR were common in the Caspian Sea region. Seventeen accessions with high APR were selected for production of synthetic hexaploid wheat (SHW), using ‘TetraPrelude’ and/or ‘TetraThatcher’ as tetraploid parents. Six SHWs were produced and evaluated for APR to LR and resistance to tan spot at seedling stage. Genetic analysis and mapping of APR introgressed from accession TA2474 was investigated in recombinant inbred lines (RIL) population derived from cross between SHW, TA4161-L3 and spring wheat cultivar, ‘WL711’. Genotyping-by-sequencing approach was used to genotype the RILs. Maximum disease severity (MDS) for LR was significantly correlated among all experiments and APR to LR was highly heritable trait in this population. Nine genomic regions significantly associated with APR to LR were QLr.ksu-1AL, QLr.ksu-1BS, QLr.ksu-1BL.1, QLr.ksu-1BL.2, QLr.ksu-2DS, QLr.ksu-2DL, QLr.ksu-5AL, QLr.ksu-5DL and QLr.ksu-6BL. Association of QLr.ksu-1BL.1 with marker Xwmc44 indicated this locus could be slow-rusting APR gene, Lr46/Yr29. QTLs detected on 2DS, 2DL and 5DL were contributed by TA4161-L3 and are novel, along with QLr.ksu-5AL. Tan spot, caused by necrotrophic fungus, Pyrenophora tritici-repentis, has recently emerged as a damaging disease of wheat worldwide. To identify QTLs associated with resistance to Race 1 of P. tritici-repentis, F[subscript]2:3 population derived from cross between SHW, TA4161-L1 and winter wheat cultivar, ‘TAM105’ was used. Two major effect QTLs, QTs.ksu-1AS.1 and QTs.ksu-7AS were significantly associated with tan spot resistance and contributed by TA4161-L1. QTs.ksu-7AS is a novel QTL and explained 17% of the phenotypic variation. Novel QTLs for APR to LR and tan spot identified in SHWs add new variation for broadening the gene pool of wheat and providing resources for breeding of durable resistant cultivars.
Hatzig, Sarah Vanessa [Verfasser]. "Breeding for climate change : genetics and physiology of seed vigor, seedling vigor and early drought resistance in winter oilseed rape (Brassica napus L.) / Sarah Vanessa Hatzig." Gießen : Universitätsbibliothek, 2015. http://d-nb.info/108012019X/34.
Повний текст джерелаSchnaithmann, Florian [Verfasser], Klaus [Akademischer Betreuer] Pillen, and Gunter [Akademischer Betreuer] Backes. "Mapping of quantitative trait loci regulating nitrogen stress tolerance and leaf rust seedling resistance in two selected populations derived from crosses between exotic and elite barley : [kumulative Dissertation] / Florian Schnaithmann ; Klaus Pillen, Gunter Backes." Halle, 2016. http://d-nb.info/1116951517/34.
Повний текст джерелаStewart, Alan V. "Plant breeding aspects of ryegrasses (Lolium sp.) infected with endophytic fungi." Phd thesis, University of Canterbury. Lincoln College, 1987. http://theses.lincoln.ac.nz/public/adt-NZLIU20071005.172250/.
Повний текст джерелаKännaste, Astrid. "Volatiles of Conifer Seedlings : Compositions and Resistance Markers." Doctoral thesis, KTH, Organisk kemi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4723.
Повний текст джерелаQC 20100818
Kännaste, Astrid. "Volatiles of conifer seedlings, composition and resistance markers /." Stockholm : Kemi, Chemistry, Kungliga Tekniska högskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4723.
Повний текст джерелаLehto, Tarja Helena. "Role of mycorrhizas in drought resistance of Sitka spruce seedlings." Thesis, University of Edinburgh, 1989. http://hdl.handle.net/1842/11045.
Повний текст джерелаGiffard, Brice. "Influence des interactions biotiques complexes sur la régénération des essences forestières feuillues." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14319/document.
Повний текст джерелаHerbivory is thought to depend on intrinsic plant resistance traits and negatively affect survival and growth of plants. Predators can depress herbivore populations and thereby indirectly limit the consumption of primary producers. The surrounding vegetation is also expected to modify the interactions between a focal plant, its herbivores and their natural enemies. The surrounding vegetation may disrupt the colonisation and the consumption of a focal plant by insect herbivores, providing associational resistance. Increasing diversity of neighbouring vegetation can decrease resource availability or enhance herbivores control by predators. By contrast, associational susceptibility may occur with higher levels of herbivory in a focal plant in more diverse plant communities. We tested 1) the effect of the neighbouring vegetation on the levels of herbivory on seedlings, 2) the indirect impact of predators on herbivores and subsequent herbivory, and 3) the interactions between surrounding vegetation, focal plants, herbivores and predators. We examined the damage caused by insect herbivores on three native broadleaved species. We then compared the importance of taxonomic similarity between seedlings and canopy tree species and the structure and composition of surrounding vegetation at both large- and small-scales. Birds are vertebrate predators likely to limit damage to plants and facilitate plant growth by consuming herbivorous insects. We estimated their effects by excluding them from focal plants, and compared their interactive effects with vegetation diversity or removal. The effects of surrounding vegetation and avian predation were also disentangled on concealed- vs. external-feeding guilds (predation sensitivity) and specialist- vs. generalist-insects.Surrounding vegetation of focal seedlings influences the abundance of insect herbivores and damage. Specialist insects (leaf miners) are affected by the understorey vegetation close to oak seedlings, decreasing with its presence or structural diversity. The damage caused by generalist insects depend on the large-scale composition of plant communities, and increase with tree species richness and cover or on conspecific forest habitats. Exclusion of insectivorous birds affects insect herbivory in a species-specific manner, and also greatly varies with forest habitats and presence of vegetation around focal plants. The indirect effect of bird predation on leaf damage is observed on seedlings beneath noncongeneric canopy trees. The removal of local surrounding vegetation affects the top-down effect of insectivorous birds on insect herbivores, according to their sensitivity to predation and the accessibility of preys. To conclude, our studies provide experimental evidences of interactive effects between bird predation and neighbouring vegetation on insect herbivores and levels of herbivory. These indirect effects are strongly related to the specialisation of herbivores and to their sensitivity to bird predation
Stattin, Eva. "Root freezing tolerance and storability of Scots pine and Norway spruce seedlings /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5639-8.pdf.
Повний текст джерелаWen, Kui. "Down-regulation of defense gene transcripts of Rhizoctonia solani-infected bean seedlings in response to inoculation with non-pathogenic fungi." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80895.
Повний текст джерелаDanusevicius, Darius. "Early genetic evaluation of growth rhythm and tolerance to frost in Picea abies (L.) Karst /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5637-1.pdf.
Повний текст джерелаAdomas, Aleksandra. "Transcript profiling of the Heterobasidion-conifer pathosystem : host and pathogen responses to biotic stress /." Uppsala : Dept. of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200735.pdf.
Повний текст джерелаWessels, Andries Bernardus. "Genetic characterization and fungicide resistance profiles of Botrytis cinerea in rooibos nurseries and pear orchards in the Western Cape of South Africa." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20070.
Повний текст джерелаENGLISH ABSTRACT: Botrytis cinerea Pers. Fr. [teleomorph Botryotinia fuckeliana (de Bary) Whetzel] causes serious losses of over 200 crops worldwide, including rooibos seedlings and pears. This pathogen is characterized by morphological, physiological and genetic diversity. The genetic diversity and population structure have not been investigated for B. cinerea populations in South Africa. Botrytis cinerea collected from rooibos seedlings and in pear orchards in the Western Cape of South Africa were investigated in the present study. The study was done with the aid of microsatellite markers, the amplification of mating type alleles MAT1-1 and MAT1-2 and determination of resistance towards various fungicides. Population dynamics was inferred and a similar picture emerged in both production systems. Botrytis cinerea annually causes severe losses of rooibos seedlings (Aspalathus linearis) in nurseries situated in the Clanwilliam region. Sampling was done in five nurseries and the cryptic species status of the isolates obtained was determined through restriction enzyme digestion of the Bc-hch gene. All but one (206 out of 207) of the isolates belonged to Group II or B. cinerea ‘sensu stricto’. Analysis of the B. cinerea Group II population, using seven microsatellite loci, was performed to assess the genetic population structure. Total gene diversity (H) was high, with a mean of 0.67. Two of the nurseries populations’ sample sizes were severely limited after clone correction, yet 100 genotypes were discerned among the 206 isolates genotyped. The percentage of maximal genotypic diversity (G) ranged between 16 and 68 for the five populations, with a total value of 17 for the 100 genotypes. One genotype, represented by 27 clones, was isolated from four nurseries. Relatively low but significant population differentiation was observed in total between nurseries (mean FST = 0.030, P = 0.001). The distribution of mating types MAT1-1 and MAT1-2 differed significantly from the ratio of 1:1 for the total population plus two of the nurseries’ populations. Three nursery populations had an equal mating type distribution. The index of association (IA) analyses suggests that the populations are asexually reproducing. Analysis of molecular variance (AMOVA) indicated that 97% of the total genetic variation is distributed within subpopulations. Fungicide resistance frequency against iprodione for 198 of the genotyped isolates displayed highly varying levels of resistance amongst the five nurseries. The mean total incidence of resistance towards iprodione was 43%, ranging from 0% to 81% for the five nurseries. Baseline sensitivity towards pyrimethanil yielded an average EC50 value of 0.096 mg/L. Botrytis cinerea isolates were collected from pear blossoms (Pyrus communis) in four orchards. Two orchards in the Ceres area and two in the Grabouw area were sampled from. A total of 181 isolates were collected from the four orchards. Incidence of blossom infection in the orchards ranged from 3% to 17%. Overall, there was a high incidence of isolates that had only the Boty transposable element (74%) compared to those harbouring both (Boty and Flipper), simultaneously (transposa, 24%). One isolate examined had the Flipper element only. Cryptic species status according to restriction enzyme digestion of the Bc-hch gene indicated that all the isolates belonged to Group II or B. cinerea ‘sensu stricto’. Analysis of the Group II population, through the use of seven microsatellite loci, was performed to assess the genetic population structure. Total gene diversity (H) was high, with a mean of 0.69 across all populations. Although two of the subpopulations displayed a high clonal proportion, overall 91 genotypes were discerned among the 181 isolates. The percentage of maximal genotypic diversity (G) ranged between 18 and 33 for the four populations, with a total value of 14 for the 91 genotypes. One genotype, represented by 27 clones, was isolated from all orchards. Moderate, but significant population differentiation was present in total among orchards (mean FST = 0.118, P = 0.001). The distribution of the mating types, MAT1-1 and MAT1-2, did not differ significantly from a 1:1 ratio for the total population as well as the subpopulations. Index of association (IA) analyses, on the other hand, suggests that the populations reproduce asexually. Analysis of molecular variance (AMOVA) indicated that 88% of the total genetic variation is distributed within subpopulations, 9% between subpopulations and only 3% between production areas. Fungicide resistance frequency against fenhexamid, iprodione and benomyl varied, with the highest levels of resistance present against benomyl and low levels of resistance seen towards iprodione and fenhexamid. In conclusion, this study has shown that there exist within the studied populations of B. cinerea, obtained from rooibos nurseries and pear orchards, an adaptive capacity to overcome current means of control. The use of population genetics to further our understanding of how plant pathogens interact and spread throughout a given environment is of cardinal importance in aiding the development of sustainable and integrated management strategies. Knowledge of the dispersal of B. cinerea in the two studied cropping systems has shed light on the inherent risk that it poses, and this together with knowledge of the levels of resistance that occurs should serve as an early warning to help divert possible loss of control in future.
AFRIKAANSE OPSOMMING: Botrytis cinerea Pers. Fr. [teleomorf Botryotinia fuckeliana (de Bary) Whetzel] veroorsaak ernstige verliese van meer as 200 gewasse wêreldwyd, insluitende rooibossaailinge en pere. Hierdie patogeen word deur morfologiese, fisiologiese, asook genetiese diversiteit gekenmerk. Die genetiese diversiteit en populasie-struktuur van B. cinerea populasies wat in Suid-Afrika voorkom, is nog nie ondersoek nie. Botrytis cinerea verkryg vanaf rooibossaailinge en in peerboorde in die Wes-Kaap van Suid-Afrika is ondersoek. Hierdie studie is met behulp van mikrosatellietmerkers, amplifikasie van die twee paringstipe gene (MAT1-1 en MAT1-2), asook die bepaling van weerstandsvlakke teenoor verskeie swamdoders, uitgevoer. Populasie-dinamika is afgelei en ‘n soortgelyke tendens is in beide produksie-sisteme waargeneem. Botrytis cinerea veroorsaak jaarliks ernstige verliese van rooibossaailinge (Aspalathus linearis) in kwekerye in die Clanwilliam-area. Monsters is in vyf kwekerye versamel en die kriptiese spesiestatus van die verkrygde isolate is deur restriksie-ensiemvertering van die Bc-hch geen bepaal. Almal behalwe een (206 uit 207) isolaat het aan Groep II of B. cinerea ‘sensu stricto’ behoort. Analise van die B. cinerea Groep II populasie, deur middel van sewe mikrosatellietmerkers, is uitgevoer om die genetiese populasiestruktuur te bepaal. Totale geendiversiteit (H) was hoog, met ‘n gemiddelde van 0.67. Alhoewel twee van die kwekerye se monstergrootte erg ingeperk is ná kloonverwydering, is daar nogtans 100 genotipes onder die 206 isolate wat geïsoleer is, waargeneem. Die persentasie van maksimale genotipiese diversiteit (G) het tussen 16 en 68, vir die vyf populasies, gewissel, met ‘n totaal van 17 vir die 100 genotipes. Een genotipe, verteenwoordig deur 27 klone, is uit vier kwekerye geïsoleer. Relatief lae dog noemenswaardige populasie-differensiasie is in totaal tussen kwekerye waargeneem (gem. FST = 0.030, P = 0.001). Die verspreiding van die twee paringstipes (MAT1-1 en MAT1-2) het beduidend verskil van ‘n 1:1 verhouding vir die totale populasie, asook twee van die kwekerye se populasies. Die drie oorblywende kwekerye se populasies het egter ‘n gelyke verdeling van die twee paringstipes getoon. Die indeks van assosiasie (IA) analises toon dat die populasies ongeslagtelik voortplant. Analise van molekulêre variasie (AMOVA) het aangedui dat 97% van die totale genetiese variasie binne die subpopulasies versprei is. Hoogs variërende vlakke van weerstand tussen die vyf kwekerye teenoor die swamdoder iprodioon, is vir die 198 isolate wat getoets is, gevind. Die totale gemiddelde frekwensie van weerstand teenoor iprodioon was 43%, wat tussen 0% en 81% vir die vyf kwekerye gevarieer het. Fondasie-vlak-sensitiwiteit vir pyrimethanil het ‘n gemiddelde EC50 waarde van 0.096 mg/L opgelewer. Botrytis cinerea isolate is ook vanuit peerbloeisels (Pyrus communis L.) vanuit vier boorde versamel, twee uit elk van die Ceres- en Grabouw-areas. In totaal is 181 isolate vanuit die vier boorde versamel. Die frekwensie van bloeiselinfeksie het tussen 3% en 17% gewissel. Oor die algemeen was daar ‘n hoë frekwensie van isolate wat slegs die Boty transponeerbare element teenwoordig gehad het (74%) in vergelyking met dié wat tegelykertyd beide (Boty en Flipper) teenwoordig gehad het. Een isolaat het slegs die Flipper element gehad. Bepaling van die kriptiese spesiestatus met behulp van restriksie-ensiemvertering van die Bc-hch geen het aangedui dat alle versamelde isolate tot Groep II of B. cinerea ‘sensu stricto’ behoort het. Analise van die Groep II populasie, deur middel van sewe mikrosatellietmerkers, is uitgevoer om genetiese populasie-struktuur te bepaal. Totale geendiversiteit (H) was hoog, met ‘n gemiddelde van 0.69 oor alle populasies. Alhoewel twee subpopulasies ‘n hoë klonale fraksie getoon het, is 91 genotipes tussen die 181 isolate wat verkry is, onderskei. Die persentasie van maksimale genotipiese diversiteit (G) het tussen 18 en 33 vir die vier populasies gewissel, met ‘n totale waarde van 14 vir die 91 genotipes. Een genotipe, verteenwoordig deur 27 klone, was in al vier boorde teenwoordig. Gematigde dog beduidende populasie differensiasie was in totaal tussen boorde teenwoordig (gem. FST = 0.118, P = 0.001). Die verspreiding van die paringstipes (MAT1-1 en MAT1-2) het nie betekenisvol van ‘n 1:1 verhouding vir die totale populasie, insluitende die subpopulasies, verskil nie. Indeks van assosiasie (IA) analises het egter aangedui dat die populasies ongeslagtelik voortplant. Analise van molekulêre variasie (AMOVA) het aangedui dat 88% van die totale genetiese variasie in subpopulasies te vinde was, 9% tussen subpopulasies en slegs 3% tussen produksie-areas. Frekwensie van swamdoder weerstandbiedendheid vir fenhexamid, iprodioon en benomyl het gewissel, met die hoogste vlakke teenoor benomyl waargeneem, maar baie lae vlakke teenoor fenhexamid en iprodioon. Samevattend het hierdie studie getoon dat die populasies van B. cinerea wat in hierdie twee produksie-sisteme, op rooibossaailinge en in peer boorde, ondersoek is, ‘n aanpasbaarheid toon om huidige metodes van beheer te oorkom. Die gebruik van populasiegenetika as ‘n hulpmiddel om ons kennis van patogeen-interaksies en -verspreiding te verbreed, is van kardinale belang in die ontwikkeling van geïntegreerde en volhoubare beheermaatreëls. Kennis van die verspreiding van B. cinerea in die bestudeerde gewasproduksiestelsels, werp lig op die inherente risiko wat dié patogeen inhou. Dít, tesame met kennis van die weerstandsvlakke wat voorkom, kan as ‘n vroegtydige waarskuwing dien ten einde moontlike verlies van beheer in die toekoms te help teenwerk.
Guo, Kunmei. "Functional assessment of the role of cyclic nucleotide-gates channel (CNGC10) and salt overly sensitive (SOS1) antiporter in salinity tolerance in Arabidopsis." University of Western Australia. Faculty of Natural and Agricultural Sciences, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0063.
Повний текст джерелаZabot, Lucio. "Caracterização agronômica de cultivares transgênicas de soja cultivadas no Rio Grande do Sul." Universidade Federal de Santa Maria, 2009. http://repositorio.ufsm.br/handle/1/3186.
Повний текст джерелаAiming to characterize the main transgenic soybeans cultivars used in Rio Grande do Sul, experiments were conducted during the 2007/2008 season, in Santa Maria/RS. In the field, the cultivars Relmo Anta RR 82, A 6001 RG, A 8000 RG, FUNDACEP 53 RR, FUNDACEP 54 RR, FUNDACEP 56 RR, BRS 244 RR, and CD 214 RR CD 219 RR, drilled at seeds rates of 250, 400 and 550 thousand seed ha-1 and at row spacing of 0.30, 0.45 and 0.60m. The variables were: grain yield, yield components, distribution of income in different strata of the plant, morphological characteristics, rate of soil covering and amount of light incident on the canopy. The experimental design was a randomized blocks, with 4 repetitions in trifatorial outline (9 cultivars x 3 seed rates x 3 row spacing). In laboratory, tests of peroxidase reaction had been carried through only using the tegument of the seeds or the entire seeds and also seedling color for 50 soybean cultivars. For the grain yield cultivars CD 214 RR and FUNDACEP 53 RR had the best results (3589 and 3530 kg ha-1, respectively). For the distribution of income in the plant strata, there is interaction between density of planting and row spacing, which indicate the trends for each cultivar. For the amount of light incident on the canopy, the interactions between the factors of planting density, row spacing, timing of the cycle of development and level of the canopy, combined with the architecture of each cultivar define the amount of light intercepted, after flowering. The morphological response of each cultivar is different for every situation tested, indicating the need for understanding the behavior of each material, to select the practices to maximize the yield. The use of the test of reaction of peroxidase used the entire seed can be used of so efficient form how much the traditionally used method (tegument). The identification of the seedling color may be an early way to identify varietal blend.
Com o objetivo de caracterizar as principais cultivares transgênicas de soja utilizadas no Rio Grande do Sul, foram realizados experimentos durante a safra agrícola 2007/2008, em Santa Maria/RS. Em campo, as cultivares Relmo Anta 82 RR, A 6001 RG, A 8000 RG, FUNDACEP 53 RR, FUNDACEP 54 RR, FUNDACEP 56 RR, BRS 244 RR, CD 214 RR e CD 219 RR foram submetidas às densidade de semeadura de 250, 400 e 550 mil semente ha-1 e aos espaçamentos entre linhas de 0,30, 0,45 e 0,60m. As variáveis avaliadas foram: rendimento de grãos, componentes do rendimento, distribuição do rendimento em diferentes estratos da planta, características morfológicas, taxa de cobertura do solo e quantidade de luz incidente no dossel. O delineamento experimental utilizado foi o de blocos ao acaso, com 4 repetições, no esquema trifatorial (9 cultivares x 3 densidades de semeadura x 3 espaçamentos entre linhas). Em laboratório, foram realizados testes de reação da peroxidase utilizando somente o tegumento das sementes ou as sementes inteiras e também coloração do hipocótilo para 50 cultivares de soja. Para o rendimento de grãos as cultivares CD 214 RR e FUNDACEP 53 RR apresentaram os melhores resultados (3589 e 3530 kg ha-1, respectivamente). Para a distribuição do rendimento nos estratos da planta, existe interação entre densidade de semeadura e espaçamento entre linhas, os quais indicam as tendências para cada cultivar. Para a quantidade de luz incidente no dossel, as interações entre os fatores densidade de semeadura, espaçamento entre linhas, época do ciclo de desenvolvimento e nível do dossel, aliados à arquitetura de cada cultivar definem a quantidade de luz interceptada, após o florescimento. A resposta morfológica de cada cultivar é diferenciada para todas as situações testadas, indicando a necessidade do conhecimento do comportamento de cada material, para a escolha das práticas que visem maximizar o rendimento de grãos. O uso do teste de reação da peroxidase utilizando a semente inteira pode ser utilizado de forma tão eficiente quanto o método tradicionalmente utilizado (tegumento). A identificação da coloração do hipocótilo pode ser uma forma precoce de identificar mistura varietal.
Cowger, Christina. "Cephalosporium stripe of wheat : seedling-based resistance screening and pathogenic variability." Thesis, 1997. http://hdl.handle.net/1957/33687.
Повний текст джерелаGraduation date: 1998
Junior, Adolar Freitag. "A "Pan American" approach to durable crown rust resistance in oats : evaluation of a seedling resistance covariance method /." Diss., 2010. http://purl.umn.edu/90938.
Повний текст джерелаKennett, Raymond Matthew. "The Evaluation of High Tannin Cotton Lines for Resistance to Rhizoctonia solani and Pythium aphanidermatum." 2009. http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7621.
Повний текст джерелаyueh-chi, Han, and 韓岳麒. "Resistance mechanism of rice seedlings to bentazon herbicide among rice lines." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/50617064785995792397.
Повний текст джерела國立中興大學
農藝學系
88
Bentazon is usually used in weed control for rice and peanut crops. If the growth of rice, cv. TNG67, seedlings was affected and how the physiological response was influenced by bentazon, especially for the resistant- and the susceptible-lines among Japonica- and Indica-type rice, were investigated. According to the dose-response to bentazon of five growth characters including plant height, shoot fresh weight, total chlorophyll, chlorophyll a and chlorophyll b of TNG67 seedlings at the V3 stage, the effective concentration of leaf-applied bentazon causing 50% reduction of response (EC50) was determined. And further study on the physiological resistant mechanism existed in bentazon-resistant and -susceptible lines of rice under this concentration of bentazon was conducted. As a result of screening the bentazon-resistant and —susceptible lines of rice, lines M202 and FSK are referred to resistant- and susceptible-line, respectively, among Japonica-type rice, as well as the TCSW1 and IR36 are referred to resistant- and susceptible-line among Indica-type, respectively. The bentazon-resistant line, M202, and TNG67 were suffered from little or a slight visible injury, photosynthesis inhibition and accumulation of MDA after bentazon application compared to other lines. Further analysis of the physiological mechanism of resistance for the bentazon-resistant and -susceptible lines among Japonica- and Indica-type rice was conducted. Experimental results indicate that the resistant line of Japonica-type, M202 and TNG67, absorbed more 14C-bentazon, but most of 14C-isotopes absorbed either accumulated in bentazon-treated leaf or translocated out of the treated leaf to older leaves subsequently. It is also found that the phytotoxicity resulted from residual bentazon and its metabolite was slight in these two rice lines. The hydroxybentazon (bentazon-6-OH) could be detected in the bentazon-resistant rice lines, M202, but not in other rice lines, indicating that M202 and TNG67, especially for the former line had stronger ability to metabolite more bentazon. For the bentazon-susceptible lines, FSK and IR36, which absorbed less 14C-bentazon during treatment but most of the 14C-isotopes absorbed translocated out of treated leaf and accumulated in young leaves subsequently. More accumulation of bentazon at the younger leaf might result in death of rice seedlings. In addition, more residual bentazon and stronger phytotoxicity were also confirmed in these two bentazon-susceptible lines. And less polar metabolite was obtained. This result indicates that the bentazon-sensitivity of FSK and IR36 were due mainly to the lower ability of bentazon metabolism. Reviewing the experimental results of this study, it suggested that the bentazon-resistant mechanism existed in resistant lines, M202 and TNG67, is primarily result from the stronger metabolism of bentazon, especially the generation of bentazon-6-OH for the line M202. Besides, that the most of absorbed bentazon translocated to older leaves and/or deposited at the site of bentazon application also involved in the resistance mechanism.
Vranjic, John Anton. "Whole plant responses of eucalypt seedlings to infestation by scale insects." Phd thesis, 1993. http://hdl.handle.net/1885/140631.
Повний текст джерелаBussey, Melinda Jane. "Development of a leaf disc assay for detecting resistance to early blight on potato seedlings." 1988. http://catalog.hathitrust.org/api/volumes/oclc/19062308.html.
Повний текст джерелаRamatsitsi, Mukondeleni Ndivhuwo. "Mechanism of resistance to Meloidogyne Incognita and Meloidogyne Javanica in Cucumis Africanus and Cucumis myriocarpus seedlings." Thesis, 2017. http://hdl.handle.net/10386/1935.
Повний текст джерелаRoot-knot (Meloidogyne species) nematodes are economically destructive pathogens of over 3000 species, whereas others have resistance to Meloidogyne species. Wild watermelon (Cucumis africanus) and wild cucumber (Cucumis myriocarpus) are highly resistant to Meloidogyne species, particularly M. incognita and M. javanica. The two Cucumis species are used in inter-generic grafting with watermelon (Citrullus lanatus) as nematode resistant rootstocks. Also, the two Cucumis species are used in traditional medicine and in plant-parasitic nematode management as phytonematicides. The form of nematode resistance, which is essential in plant breeding, is not documented for the two Cucumis species. The objective of this study was to determine the form of nematode resistance in the two Cucumis species to M. incognita and M. javanica under greenhouse conditions. Four parallel experiments were each conducted under greenhouse conditions. Uniform six-week old Cucumis seedlings were transplanted into 250 ml polystyrene cups filled with 200 ml growing medium of steam-pasteurised fine sand. A week after transplanting, Cucumis seedlings were each infested by dispensing approximately 100 M. incognita second-stage juveniles (J2) or M. javanica J2 using a 20 ml plastic syringe by placing into 5-cm-deep furrow around the seedling stem and covered with growing medium. Treatments (periodic harvest intervals) were arranged in a randomised complete block design, replicated five times. Five seedlings from each experiment were harvested every second day, for 30 days, with stained roots being assessed for necrotic spot (suberised cells) number, giant cell number, proliferation of rootlet interference number and root gall number. Periodic harvest intervals were highly significant (P ≤ 0.01) on necrotic spot number, proliferation of rootlet interference number and root gall number in C. africanus-M. incognita relations, but were not significant for giant cell number. Treatments contributed 59, 64 and 50% in total treatment variation (TTV) of necrotic spot number, proliferation of rootlet interference number and root gall number, respectively. Harvest period had highly significant effects on necrotic spot number, giant cell number, proliferation of rootlet interference number and root gall number in C. africanus-M. javanica relations. Treatments contributed 55, 71, 63 and 59% in TTV of necrotic spot number, giant cell number, proliferation of rootlet interference number and root gall number, respectively. Periodic harvest intervals were significant (P ≤ 0.05) on giant cell number and highly significant on root gall number in C. myriocarpus-M. incognita relations. However, there were no significant treatment differences on necrotic spot number and proliferation of rootlet interference number. Treatments contributed 57 and 57% in TTV of root gall number and giant cell number, respectively. Harvest period had highly significant effects on giant cell number, proliferation of rootlet interference number and root gall number, but were not significant on necrotic spot number in C. myriocarpus-M. javanica relations. Treatments accounted for 67, 49 and 53% in TTV of giant cell number, proliferation of rootlet interference number and root gall number, respectively. In conclusion, the mechanism of resistance to M. incognita and M. javanica in both C. africanus and C. myriocarpus was post-infectional nematode resistance, which has attributes for introgression into commercial nematode-susceptible Cucumis cultivars.
Agricultural Research Council (ARC), National Research Foundation of South Africa; and the ARC-Universities Collaboration Centre for Smallholder Farmers
Jimenez-Casas, Marcos. "Effects of NaCl on growth and physiology of Pinus leiophylla seedlings." Phd thesis, 2009. http://hdl.handle.net/10048/446.
Повний текст джерелаSmit, Julie. "Effects of root growth and physiology on drought resistance in Douglas-fir, lodgepole pine, and white spruce seedlings." Thesis, 1993. https://dspace.library.uvic.ca//handle/1828/9656.
Повний текст джерелаGraduate
Snyman, Marisha. "Salicylic acid-mediated potentiation of Hsp70 in tomato seedlings is modulated by heat shock factors." Thesis, 2012. http://hdl.handle.net/10210/6172.
Повний текст джерелаIn plants, salicylic acid (SA) is a signaling molecule that regulates disease resistance responses such as systemic acquired resistance (SAR) and the hypersensitive response (HR), and has been implicated in both basal and acquired thermotolerance. It has also been shown that SA enhances heat-induced Hsp/Hsc70 accumulation in plants. In this study, temperature studies revealed that heat shock (HS) at 40 °C for 30 min significantly induced Hsp/Hsc70 accumulation in 3-week old tomato (UC82B) seedlings. Time- and dose-responsive studies showed that 0.1 mM SA for 17 hrs was unable to induce Hsp/Hsc70 but in combination with HS significantly (P > 0.001) potentiated this response. To investigate the mechanism of SA-mediated, heat-induced Hsp/Hsc70 potentiation, tomato seedlings were treated with either SA alone, HS or both, before analyses of hsp70 mRNA, Hsf DNA-binding and gene expression of hsp70, hsfAl, hsfA2 and hsfEll. SA alone established Hsf DNA-binding, but was not accompanied by increased Hsp70 accumulation or expression of hsp70 mRNA. SA had no significant effect on hsfA2 and hsf81 gene expression, but increased the basal levels of hsfAl. In heat-shocked plants, Hsf DNA-binding was enhanced, and increased hsfAl, hsfA2 and hsfB1 expression preceded accumulation of Hsp70. The combined treatment of SA and HS resulted in potentiated Hsf DNA-binding, enhanced expression of hsp70, hsfAl, hsfA2 and hsfB1, leading to potentiated levels of Hsp/Hsc70. Since increased hsp70 and hsf gene expression coincided with increased levels of Hsp70 accumulation, it is likely that the SA-mediated potentiation of Hsp70 is due to the ability of SA to regulate Hsfs during HS. This study therefore proposes a mechanism for the potentiation of Hsp70 by SA in the presence of heat, which might contribute to our understanding of the role SA plays in the heat shock response and thermotolerance.
Meehan, Mitchell Elwin. "A comparison of techniques for screening for resistance to the chinch bug, Blissus leucopterus leucopterus (Say), in sorghum." 1985. http://hdl.handle.net/2097/27497.
Повний текст джерелаChen, Yun-Hao, and 陳昀皓. "Studies on Inoculation Methods of Guava (Psidium guajava L.) Seedlings with Nalanthamala psidii (syn. Myxosporium psidii) and the Screening for Resistance." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/98794940895667522998.
Повний текст джерела國立臺灣大學
園藝學研究所
100
Myxosporium wilt, caused by the pathogen Nalanthamala psidii (Sawada et Kurosawa) Schroers & M. J. Wingf. (≡Myxosporium psidii Sawada et Kurosawa), belongs to one of systemical fungal diseases. This disease has been the most severe and destructive disease of guava (Psidium guajava) cultivation in Taiwan since the 1970s due to the development of pruning techniques for nonseasonal production. The pruning techniques result in numerous wounded sites and increase chances for the invasion of this pathogen. No chemical could prevent or cure this disease and no other solution is available except to burn and remove infected trees from the orchards immediately as the symptoms ocurred. Therefore, breeding for disease resistance is requied. The objectives for the present studies were to: (1) study the effectiveness of inoculation methods for guava seedlings; (2) screening seedlings for N. psidii resistance; (3) evaluate the pathogenicity of N. psidii culture filtrate to seedlings. In the present study, pitiching and root trimming severely injured seedlings and caused a lot portion of seedlings died. Therefore, the effectiveness of the two inoculation methods could not be compared; and thus, the effects of wounding method, seedling stage and inoculum concentration on inoculation of N. psidii could not be determined. Among 2760 seedlings we screened after 3 inoculations within 2 years, 132 puataive resistant plants were obtained. Half of them were ‘Pei-pa’ open-pollinated (OP) progenies. After wounding branches of ‘Pei-pa’ hybrid and OP seedlings of other lines were inoculated with agar plugs of N. psidii Mp-02 isolate, wilting symptoms of most plants only occurred above the wounds. The observation period, 2 months, was not long enough to determine their resistance/susceptibility. However, pathogenicity of N. psidii culture filtrate to guava seedlings could not be confirmed.
Hsieh, Tzu-Yang, and 謝子揚. "Evaluation for efficacy of total protein extracted from Alternaria tenuissima APR01 on inducing Chinese cabbage seedlings resistant to Rhizoctonia damping-off." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/33191374976371785045.
Повний текст джерела國立中興大學
植物病理學系所
98
Twelve isolates of Alternaria spp. were isolated from various crops in Taiwan. Those fungi were respectively grown in liquid culture media for 5-7 days and harvested their mycelia. The mycelial samples were pulverized in liquid nitrogen, and then homogenized with precooled Tris-buffer, estimated the quantity of their total protein by the Bradford method, bovine serum albumin (BSA) solution was used as a standard, the absorbance value equal to 2 µg BSA/ml. Spraying the mycelial extracts obtained from Alternaria spp. on Chinese cabbage seedlings inoculated with Rhizoctonia solani AG-4, APR01-TP and ACO01-TP, were able to reduce 33.33% disease incidence of Rhizoctonia damping-off of Chinese cabbage seedlings. Dipping germinated Chinese cabbage seeds with each of mycelial extracts obtained from 12 isolates of Alternaria spp., ATA01-TP, ABR03-TP, ALY01-TP, AOR01-TP and APR01-TP was respctively able to promote the extension of Chinese cabbage roots as well as to enhance development of their lateral roots. Especially, the mycelial extract of APR01 was more effective in stimulating the growth of plants at 36.56%. APR01 was identified as Alternaria tenuissima according to its conidial morphology, conidigenous cells, and ITS sequencing. In greenhouse tests, spraying the mycelial extract from A. tenuissima APR01 once or thrice on Chinese cabbage seedlings grown on soil infested with R. solani AG-4 RST-04, the fresh weight of Chinese cabbage seedlings were heavier up to 38.3% and 48% compared to untreated control. Inoculating mycelial discs of R. solani AG-4 RST-04 on Chinese cabbage leaves after sparying mycelial extract of A. tenuissima APR01, the expansion of the lesion size were slower compared to the control. It was proved that the mycelial extract of A. tenuissima APR01 could not inhibit mycelial growth of R. solani AG-4 RST-04. To estimate the activity of phenylalanine ammonia lyase (PAL) and peroxidase (POD) in Chinese cabbage seedlings after spraying the mycelial extract of A. tenuissima APR01 and inoculating R. solani AG-4 RST-04, the enzyme activity of the PAL and POD in treated plants were higher than the control. These results suggested that there were some elements existed in mycelial extract of isolate APR01 were able to induce Chinese cabbage seedlings resistant against the pathogen. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was performed for mycelial extract of A. tenuissima APR01 and the bands were displayed on polyacrylamide gel stained with CBR. Mycelial extract of A. tenuissima APR01 was heated at 50 ℃ water bath and lost its biological activity. The effective component of the mycelial extract of A. tenuissima APR01 was not ultra-filtrated in the membrane tubing with molecular weight cut-off of 10,000. Therefore, the major activity of mycelial extract of A. tenuissima APR01 is a protein with > 10 kilodalton of molecular weight.
Aldana, Juan Andres. "Resistance mechanisms to Didymascella thujina (Durand) Maire in Thuja plicata Donn ex D. Don, Thuja standishii (Gord.) Carrière and Thuja standishii x plicata." Thesis, 2018. https://dspace.library.uvic.ca//handle/1828/10058.
Повний текст джерелаGraduate
2020-08-31