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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Interactions between atmospheric nitrogen fixation and bioavailability of phosphorus in common bean (Phaseolus vulgaris L.) in some phosphorus-deficient soils of the Mediterranean basin / Interactions entre fixation d'azote atmosphérique et biodisponibilité du phosphore chez le haricot (Phaseolus vulgaris L.) dans quelques sols déficients en phosphore du bassin Méditerranéen

Aslan Attar, Hesham 14 September 2011 (has links)
La déficience des sols en éléments minéraux, particulièrement le phosphore (P) est une limitation majeure pour la croissance et le développement des légumineuses fixatrices d’azote. L’application des fertilisants phosphatés est une pratique traditionnelles pour satisfaire les besoins des plantes en P. Ainsi, pour tester l’efficacité d'utilisation du P pour la fixation symbiotique de l’azote (FSN) sous déficience en P, plusieurs lignées recombinantes (RILs) de haricot contrastantes dans leurs tolérance au déficit en P ont été utilisées. L’objectif principal de cette étude est d’évaluer l’aptitude de ces RILs pour l’amélioration de la fertilité phosphatée des sols déficients en P et sa relation avec la croissance et la nodulation de la légumineuse. Pour atteindre ces objectifs, des expériences ont été réalisées sous serre et en champs d'agriculteurs. Sous conditions contrôlées (serre) et non contrôlées (champs), les résultats ont montré une diminution du pH des sols associée à une augmentation du P assimilable. Une telle augmentation de la disponibilité du P a eu un effet positif sur la nodulation et la croissance de certaines des RILs testées. Aussi, l’amélioration de l’aptitude de ces RILs à fixer l’azote atmosphérique et l’élévation de la libération des protons H+ par les racines nodulées ont été quantifiés en milieu contrôlé. Ainsi la diminution du pH du sol a permis de réduire l’indisponibilité du P dans la solution du sol en le transformant en une forme directement biodisponible pour ces plantes. En outre, les résultats ont montré des différences significatives entre les différentes RILs en termes de la biomasse aérienne et nodulaire selon les sites d'observation. Nous concluons que, outre leur aptitude de fixation d’azote, l’utilisation efficace du phosphore pour sauver des engrais minéraux et de réduire les risques de pollution et pourrait améliorer la disponibilité des sols P. / The deficiency of soil minerals, particularly phosphorus (P) is a major limitation for growth and development of nitrogen-fixing by legumes. The application of phosphate fertilizers is a traditional practice to meet the needs of plant P. Thus, to test the effectiveness of use of P for symbiotic nitrogen fixation (NSF) under P deficiency, several recombinant inbred lines (RILs) of beans in their contrasting tolerance to P deficiency have been used. The main objective of this study is to assess the ability of these RILs to improve the fertility of soils deficient in phosphorus (P) and its relationship with growth and nodulation of the legume. To achieve these objectives, some experiments were conducted in greenhouses and fields. Under controlled conditions (greenhouse) and uncontrolled conditions (field), the results showed decreasing in soil pH associated with Proton release H+ and P acquisition. The increasing in available P had a positive effect on nodulation and growth of some RILs tested. Also, improving the ability of these RILs to fix atmospheric nitrogen and release H+ by nodulated roots were quantified in a controlled environment. Thus the decreasing in soil pH has reduced the un-availability of P in soil solution by transforming it into a bio-available form to the plants. In addition, the results showed significant differences between RILs in biomass and nodulation as observation in sites. We conclude that, in addition to their ability to fix nitrogen, effective use of phosphorus to save mineral fertilizer and reduce the pollution risks and could improve the availability of soil P.
92

Genetic Analysis of Marsh Spot Resistance in Cranberry Common Bean (Phaseolus vulgaris L.)

Jia, Bosen 22 August 2022 (has links)
Cranberry common bean (Phaseolus vulgaris L.) is planted worldwide and consumed as a critical food source of human protein, fibre, carbohydrates, and minerals. Marsh spot (MS) is a physiogenic disorder which severely impacts seed quality in common beans. Previous studies indicate that MS involves a nutritional disorder caused by Mn deficiency. However, the inheritance and genetic mechanism of MS resistance are still not fully understood. To investigate the genetics of MS resistance, a population of 138 recombinant inbred lines (RILs) was developed from a bi-parental cross between a susceptible cultivar Messina and a resistant cultivar Cran09. The population and its two parents were evaluated for MS resistance during five consecutive years from 2015 to 2019 in both sandy and heavy clay soils in Morden, Manitoba, Canada. The severities of MS were rated and subsequently converted to MS resistance index (MSRI) and MS incidence (MSI). Statistical analyses indicated that MSI and MSRI were highly correlated (r = 0.96-0.99) and had high broad-sense heritability (H²) of 86.5% and 83.2%, respectively. Joint segregation analysis (JSA) of 18 phenotypic datasets from five years and two soil types showed that MS resistance was controlled by four major genes with genetic interactions - one of which may suppress the additive effect of the other three genes. To identify the quantitative trait loci (QTL) and the candidate genes associated with the MS resistance, the 138 RILs and the two parents were sequenced using genotyping by sequencing approach. A total of 52,676 SNPs were detected. After further filtering with a threshold of minor allele frequency > 0.01 and call rate > 20%, 2,061 SNPs were retained and then imputed for genetic map construction and QTL mapping. A genetic map consisting of 2,058 SNP markers on 11 linkage groups or chromosomes was constructed, which covered 1,004 recombination blocks with a total length of 6,449 cM and an average block of 6.42 cM. Three linkage map-based QTL-mapping models ICIM-ADD, ICIM-EPI, and GCIM and one genome-wide association study (GWAS) model RTM-GWAS for 18 phenotypic datasets from different years and soil types were used for identification of QTL. A total of 36 QTL, including 21 of additive and 15 of epistatic effects, were identified. Functional gene annotation analysis revealed 151 Mn-related candidate genes across the common bean reference genome and 17 of them harbored the six QTL discovered in this study. In conclusion, MS resistance in common bean is a highly heritable trait and controlled by several major and minor genes. The results of JSA and QTL mapping advance the current understanding of the genetic mechanisms of MS resistance in cranberry common bean, and provide additional resources for application in genomics-assisted breeding and potential isolation and functional characterization of the candidate genes.
93

Avaliação da capacidade reprodutiva de populações de Pratylenchus spp. frente a diferentes espécies vegetais / Reproductive fitness of Pratylenchus spp. populations in different plant species

Bonfim Junior, Mauro Ferreira 03 February 2010 (has links)
Os nematoides que atualmente tem sido classificados como P. coffeae, demonstram ampla variabilidade morfológica, molecular e quanto à reação à diferentes hospedeiros. Por conseguinte, é essencial que se identifique corretamente as espécies e que se conheça a capacidade de parasitismo em alguns hospedeiros, para que se possa estabelecer medidas de controle e estimar eventuais riscos da entrada de um patógeno em uma área com hospedeiro suscetível. Neste sentido, a presente pesquisa propõe, numa primeira parte, uma medida de controle de P. jaehni (K5), que é muito agressivo à cafeeiro arábico, baseada no uso de plantas má hospedeiras. Na segunda parte deste trabalho é realizada uma caracterização da reação de diferentes espécies vegetais à quatro populações de Pratylenchus spp. Em virtude do exposto, este estudo objetivou avaliar a reação de diferentes cultivares de feijoeiro comum frente à P. jaehni (K5), visando seu possível uso no manejo de áreas cafeeiras infestadas e caracterizar a reação de diferentes espécies vegetais de importância econômica (café, porta-enxertos cítricos, banana e sorgo) frente à quatro populações de Pratylenchus spp. As populações inciais utilizadas nos experimentos variaram entre 180 e 200 nematóides. Em todos os experimentos, os nematóides foram extraídos das raízes pelo método de Coolen e D´Herde (1972) e, eventualmente, do substrato pelo método de Jenkins (1964). Foram realizados três ensaios: i) o primeiro com feijoeiro comum, onde todas as cultivares utilizadas foram resistentes à P. jaehni (K5), inclusive na réplica; ii) o segundo com porta-enxertos cítricos, no qual somente o limão-cravo foi hospedeiro de P. jaehni (K5); iii) o terceiro, no qual foi utilizado café, limão-cravo, banana e sorgo para o conhecimento das respectivas reações frente à 4 populações de Pratylenchus spp. Neste último experimento ocorreu uma reação hospedeira diferenciada para cada população. De acordo com os resultados, concluise que as cultivares de feijoeiro comum utilizadas apresentam potencial de uso em áreas cafeeiras infestadas por P. jaehni (K5), em consórcio ou em áreas de renovação de cafezal, e que as populações de Pratylenchus spp. são capazes de se reproduzir de forma diferenciada frente às espécies vegetais testadas. / Nematode populations that have been classified as P. coffeae show wide morphological, molecular and host range variability. Therefore, is essential the correct identification of the species and the knowledge about its parasitism capacity on some hosts, to ensure appropriate control measures and to estimate the entry risks of a pathogen in an area with susceptible host. In this sense, the present research report, firstly, propose a control measure of P. jaehni (K5), which is very aggressive to the arabic coffee, based on the use of poor host plants. In the second part, was carried out a host status evaluation of different plant species to four populations of Pratylenchus spp. In this context, were evaluated the reaction of different common bean cultivars to P. jaehni (K5), for its possible use in management of coffee areas infested with this nematode, and characterized the response of different economic important plant species (coffee, citrus rootstocks, banana and sorghum) to four populations of Pratylenchus spp (IB01P, IB02P, K5 e C1). The initial population used in experiments ranged between 180 and 200 nematodes. In all experiments, nematodes were extracted from roots by Coolen e D\'Herde´s method (1972) and eventually from the substrate by Jenkins´ method (1964). Three assays were conducted and results was as following: i) in the first one, with common bean, all tested cultivars were resistant to P. jaehni (K5), including the replica; ii) in the second one, with rootstocks, only rangpur lime was a good host of P. jaehni (K5); iii) in the third one, in which was used coffee, rangpur lime, banana and grain sorghum, was observed a differential host reaction for each nematode population evaluated. According to the present results, we suggest that common bean cultivars tested have great potential for use, or in intercropping or in crop rotation, in coffee areas infested by P. jaehni (K5) and populations of Pratylenchus spp. have different reproductive fitness in the plants species tested.
94

Mapeamento de genes análogos de resistência a patógenos em feijão (Phaseolus vulgaris L.) / Mapping resistance gene analogs in common bean (Phaseolus vulgaris L.)

Santini, Luciane 27 January 2010 (has links)
No presente trabalho, a metodologia NBS-profiling foi utilizada para o desenvolvimento de marcadores RGA (Resistance Genes Analogs) em duas populações de Phaseolus vulgaris, sendo uma derivada do cruzamento entre Bat 93 e Jalo EEP558 (BJ) e a outra derivada do cruzamento entre Carioca e Flor de Mayo (CFM). Uma vez identificados, foram mapeados 32 marcadores RGA na população BJ e 40 na população CFM. Nove dos marcadores alocados no mapa de ligação da população BJ se localizaram em proximidade a clusters de resistência, já identificados por outros pesquisadores. Foi realizado o sequenciamento de 32 dos RGA detectados, sendo 16 da cada população. Cinco sequências oriundas da população BJ e três sequências da população CFM apresentaram similaridade com proteínas de resistência identificadas em P. vulgaris, Glycine max e Medicago truncaluta. O mapa de ligação aqui gerado para a população CFM foi utilizado para o posicionamento de QTL (Quantitative Trait Loci) de resistência à mancha-angular (Pseudocercospora griseola (Sacc.) Crous & Braun) e ao oídio (Erysiphe polygoni DC.). Um total de 12 QTL foi mapeado, cinco associados à resposta à mancha angular e sete à resposta ao oídio. / In the presenty study, the NBS-profiling method was used for the development of RGA (Resistance Gene Analogs) markers in two populations of Phaseolus vulgaris, one derived from a cross between \'Bat 93\' and \'Jalo EEP558\' (BJ) and the other derived from a cross between \'Carioca\' and \'Flor de Mayo (CFM). After their identification, 32 RGA markers were mapped on the BJ population and 40 on the CFM population. Nine of the markers assigned to the linkage map of the BJ population were located in the proximity to clusters of resistance already identified by other researchers. We carried out the sequencing of 32 out of the RGA detected, being 16 from each population. Five sequences derived from the BJ population and three sequences from the CFM population showed similarity to resistance proteins identified in P. vulgaris, Glycine max and Medicago truncaluta. The linkage map here generated for the CFM population was used for the positioning of QTL (Quantitative Trait Loci) for resistance to angular leaf spot (Pseudocercospora griseola (Sacc.) Crous & Braun) and powdery mildew (Erysiphe polygoni DC.). Twelve QTL were mapped, five associated to the response to the angular leaf spot and seven to the powdery mildew.
95

Consórcio de milho com adubos verdes e manejo da adubação nitrogenada no cultivo de feijão em sucessão no sistema integração lavoura-pecuária no cerrado / Nitrogen fertilization management in bean cultivated after maize-legumes intercropping in the Crop-Livestock Integration system in Brazilian Savannah

Oliveira, Priscila de 29 June 2010 (has links)
Foram realizados dez experimentos envolvendo as culturas de feijão e milho consorciado com leguminosas e/ou Brachiaria brizantha, nas safras de verão de 2008/2009, inverno de 2009 e verão de 2009/2010, em dois municípios de estado de Goiás (GO). Em Ipameri-GO, a área foi cultivada com soja por vários anos e milho consorciado com B. brizantha na safra que precedeu a implantação dos experimentos. Em Santo Antônio de Goiás-GO, a área é mantida com a rotação de milho e soja com a forrageira B. brizantha, em esquema trienal. Os principais objetivos desses estudos foram avaliar: (i) a viabilidade do consórcio de milho com leguminosas, (ii) a resposta do feijoeiro cultivado em sucessão e (iii) o manejo do N nessas culturas. Foi constatado que em solos com média a alta fertilidade química, como os utilizados na experimentação, os consórcios de milho com B. brizantha ou com guandu-anão (Canajus cajan) ou crotalária (Crotalaria spectabilis) não interferiram na produtividade de grãos de milho na presença de N em cobertura, exceto no experimento conduzido em Santo Antônio de Goiás-GO, no qual a crotalária reduziu significativamente a produtividade do milho. Também, em ambos os locais, no consórcio simultâneo ou defasado de milho com crotalária ou guandu-anão não ocorreu liberação de nitrogênio (N) das leguminosas para o milho, medido pela produtividade de grãos, durante o ciclo das espécies. Já nos consórcios em que a B. brizantha foi mantida sem dessecação nas entrelinhas do milho, denominado de dessecação parcial, ocorreu decréscimo significativo na produtividade do milho, em relação ao cultivo em área totalmente dessecada. A análise de crescimento revelou maiores índice de área foliar (IAF) e acúmulo de massa de matéria seca da parte aérea (MSPA) para o guandu em monocultivo, sendo que para a crotalária cultivada na linha do milho, tanto o IAF quanto a MSPA aproximaram-se dos valores referentes ao monocultivo. As curvas de crescimento do milho revelaram a superioridade do cultivo com 90.kg.ha-1 de N tanto no IAF quanto na MSPA, quando comparado ao cultivo consorciado com leguminosas. No caso de Santo Antônio de Goiás-GO, na rotação trienal envolvendo espécies graníferas e forrageiras, registrou-se um acentuado aporte de N no solo, sendo obtidas altas produtividades de feijão cultivado em sucessão à pastagem, sem a aplicação de N mineral, ocorrendo, porém, aumento significativo na produtividade do feijoeiro nos tratamentos de palhadas que continham leguminosas. A aplicação de N mineral imediatamente antes da semeadura ou no estádio de plântulas do feijão e do milho teve efeito semelhante nas suas produtividades em relação à aplicação tradicional, ou seja, algumas semanas após a emergência dessas espécies. A aplicação de N mineral foi mais eficiente no aumento da produtividade de feijão irrigado quando feita próximo às fileiras de plantas ou quando o N foi incorporado mecanicamente no solo, comparados à aplicação a lanço. / Ten experiments were performed involving common beans and maize intercropped with legumes and/or Brachiaria brizantha, in the summer crops of 2008/2009, 2009 winter and summer of 2009/2010 in two municipalities in the Goiás (GO) state, Brazil. In Ipameri- GO, the area was planted with soybeans for several years and corn associated with B. brizantha in crop preceding the experiments. In Santo Antônio de Goiás-GO, the area is maintained with corn or soybean rotation with B. brizantha, in a three-year scheme. The main objectives of these studies were to evaluate the feasibility of intercropping maize with legumes and the response of common bean after it, in no-tillage system, on the mulching straws provided by the cultivation of maize intercropped with forage legumes and grasses and to study the management of nitrogen (N) in these two crops. It was found that in soils with medium to high chemical fertility, such as those used in the experiments, the intercropping of corn and B. brizantha or pigeonpea (Canajus cajan) and sunn hemp (Crotalaria spectabilis) had any influence on grain yield of maize in the presence of mineral N, except in the experiment conducted in Santo Antonio de Goiás-GO, where the sunn hemp significantly reduced corn productivity. Also, in both locations, simultaneous or lagged consortium of pigeonpea or sunn hemp with maize, there was no release of N from legumes to maize, as measured by grain productivity, during the cycle of the species. However, in the consortia in which B. brizantha is maintained without drying between the maize lines, called partial desiccation, there was a significant decrease in the yield of corn in relation to the totally desiccated area. The growth analysis showed higher leaf area index (LAI) and total dry matter accumulation (TDM) for pigeonpea grown in single system, but for sunn hemp cultivated in the corn rows, both LAI and TDM approached to its single cropping, confirming its competitiveness with corn in the intercropping system. Growth curves also showed the superiority of the corn crop with 90 kg N ha-1 in both LAI and TDM, compared to intercropping with legumes. In the case of Santo Antônio de Goiás-GO the three-year rotation involving grain species and grass forages caused an intake of N in the soil, and high yields of beans grown in rotation with pasture were obtained, without the application of mineral N, occurring, though, significant increase in grain yield in the treatments of straws containing legumes. The application of mineral N immediately before sowing or at the seedling stage of beans and corn had a similar effect on their productivity compared to traditional application, a few weeks after the emergence of these species. The application of mineral N was more efficient in increasing the productivity of beans when applied on the soil surface near the plants rows and in cases where the fertilizer was mechanically incorporated into the soil, comparing to surface-broadcasting.
96

Mapeamento de genes análogos de resistência a patógenos em feijão (Phaseolus vulgaris L.) / Mapping resistance gene analogs in common bean (Phaseolus vulgaris L.)

Luciane Santini 27 January 2010 (has links)
No presente trabalho, a metodologia NBS-profiling foi utilizada para o desenvolvimento de marcadores RGA (Resistance Genes Analogs) em duas populações de Phaseolus vulgaris, sendo uma derivada do cruzamento entre Bat 93 e Jalo EEP558 (BJ) e a outra derivada do cruzamento entre Carioca e Flor de Mayo (CFM). Uma vez identificados, foram mapeados 32 marcadores RGA na população BJ e 40 na população CFM. Nove dos marcadores alocados no mapa de ligação da população BJ se localizaram em proximidade a clusters de resistência, já identificados por outros pesquisadores. Foi realizado o sequenciamento de 32 dos RGA detectados, sendo 16 da cada população. Cinco sequências oriundas da população BJ e três sequências da população CFM apresentaram similaridade com proteínas de resistência identificadas em P. vulgaris, Glycine max e Medicago truncaluta. O mapa de ligação aqui gerado para a população CFM foi utilizado para o posicionamento de QTL (Quantitative Trait Loci) de resistência à mancha-angular (Pseudocercospora griseola (Sacc.) Crous & Braun) e ao oídio (Erysiphe polygoni DC.). Um total de 12 QTL foi mapeado, cinco associados à resposta à mancha angular e sete à resposta ao oídio. / In the presenty study, the NBS-profiling method was used for the development of RGA (Resistance Gene Analogs) markers in two populations of Phaseolus vulgaris, one derived from a cross between \'Bat 93\' and \'Jalo EEP558\' (BJ) and the other derived from a cross between \'Carioca\' and \'Flor de Mayo (CFM). After their identification, 32 RGA markers were mapped on the BJ population and 40 on the CFM population. Nine of the markers assigned to the linkage map of the BJ population were located in the proximity to clusters of resistance already identified by other researchers. We carried out the sequencing of 32 out of the RGA detected, being 16 from each population. Five sequences derived from the BJ population and three sequences from the CFM population showed similarity to resistance proteins identified in P. vulgaris, Glycine max and Medicago truncaluta. The linkage map here generated for the CFM population was used for the positioning of QTL (Quantitative Trait Loci) for resistance to angular leaf spot (Pseudocercospora griseola (Sacc.) Crous & Braun) and powdery mildew (Erysiphe polygoni DC.). Twelve QTL were mapped, five associated to the response to the angular leaf spot and seven to the powdery mildew.
97

Rhizobium inoculation, cultivar and management effects on the growth, development and yield of common bean (Phaseolus vulgaris L.)

Kellman, Anthony W. January 2008 (has links)
Genotypic differences in growth and yield of two common bean (Phaseolus vulgaris L) cultivars to Rhizobium inoculation and management were investigated. In 2003-04, the two bean cultivars (Scylla and T-49) were combined with three inoculant treatments (strains CC 511 and RCR 3644, and a control of no inoculation), two fertiliser levels (0 and 150 kg N ha⁻¹) and two irrigation treatments (irrigated and rainfed). There was no nodulation on either cultivar. To further investigate the symbiotic relationship, 16 rhizobial isolates, including the two used in the first field experiment, were combined with the cultivar Scylla and evaluated in a greenhouse. Subsequently, five Rhizobium isolates were chosen for further field evaluation, based on signs of early nodulation in the greenhouse trial. The second field experiment in 2004-05 combined the five inoculant strains (RCR 3644, UK 2, H 20, PRF 81, PhP 17 and a control) with two bean cultivars (Scylla and T-49). In the greenhouse, nodule number varied from 7 (UK 2) to 347 (H 441) nodules plant⁻¹ at 51 DAS and from 13 (UK 1) to 335 (CIAT 899) nodules plant⁻¹ at 85 DAS. In 2004-05, in the field, nodulation was also variable, ranging between 1 and approximately 70 nodules plant⁻¹, with higher nodules numbers plant⁻¹ being found on cultivar T-49. Of the isolates used in the field, strains H 20, PRF 81 and PhP 17 produced 70, 25 and 12 nodules plant⁻¹ at 70, 40 and 54 DAS respectively. Nodules formed were of various sizes and more than 80 % were pink to dark red in colour denoting the presence of leghaemoglobin and active N fixation. The remaining nodules were either green or white. The importance of selecting an appropriate cultivar for the growing conditions was highlighted in these experiments. Leaf area index, leaf area duration intercepted radiation and final utilisation efficiency were significantly affected by cultivar. In both seasons cv. T-49 reached maturity (dry seed) before Scylla, while unirrigated plants reached green pod maturity seven days before irrigated plants. Plants of cv. Scylla gave a final TDM of 730 g m⁻²; compared to the 530 g m⁻² produced by T-49. The average growth rate was 7.0 and 5.2 g m⁻² day⁻¹ for Scylla and T-49 respectively (2003-04). Plants receiving 150 kg N ha⁻¹ produced 665 g m⁻² TDM which was 12 % more than was produced by unfertilised plants. The application of 150 kg N ha⁻¹ gave an average growth rate of 6.4 g m⁻² day⁻¹ compared to 5.7 g m⁻² day⁻¹ from plants with no N. Inoculation in the field had no significant effect on TDM in both seasons. Temperature affected growth and DM accumulation. Accumulated DM was highly dependent on cumulative intercepted PAR. Air temperatures below the base temperature (10 °C) affected growth in 2004-05, resulting in plants accumulating just 0.24 g DM MJ⁻¹ PAR during early growth. This increased to 2.26 g DM MJ⁻¹ PAR when the temperature was increased above the base temperature. There was a strong relationship between LAI and intercepted PAR. A LAI of 4.0-4.5 was required to intercept 90-95 % of incident solar radiation. Cultivar significantly (p < 0.001) affected radiation use efficiency (RUE). Scylla had a RUE of 1.02 g DM MJ⁻¹ PAR compared to T-49 at 1.18 g DM MJ⁻¹ PAR. Seed yield was significantly (p < 0.001) affected by cultivar and fertiliser application. Cultivar Scylla produced 467 g m⁻² which was 76 % more than T-49, while a 12 % increase in seed yield was observed in N fertilised plants over unfertilised plants. Only cultivar significantly affected HI, while the yield components that had the greatest effect on seed yield were hundred seed weight and pods plant⁻¹. Inoculation significantly (p< 0.05) affected 100 seed weight (2004-05). Plants inoculated with strain H 20 had the highest 100 seed weight at 25.2 g with cv. Scylla producing larger seeds than T-49. The belief that local environmental conditions play a major role on field survival of bacteria, led to the use of PCR methods to identify field nodulating organisms. Amplification of genomic DNA from parent isolates using primers fC and rD generated a single band for each isolate. Isolates were identified to the species level as either Rhizobium or Agrobacterium, using the highly conserved internally transcribed spacer (ITS) region and are known to nodulate common bean. The DNA extracted from the isolates recovered from nodules of field grown beans gave multiple bands with primers fC and rD. Five distinct banding patterns were observed. All of these were different from those of parent isolates. Sequencing of the 16S rRNA demonstrated that nodules of field grown beans in Canterbury were inhabited by Pseudomonads either alone or in association with other root nodulating organisms. The inability to identify the inoculant strains in nodules of field grown beans does not rule out their infection and nodulating function in the cultivars used. The results suggest the possibility of both Rhizobium and Pseudomonads cohabiting in the nodules of field grown beans. The aggressive nature of Pseudomonads on artificial media, possibly out competing the inoculant rhizobia is proposed, leading to the inability to identify the inoculant strain from the nodules of the field grown beans by PCR methods. The need to identify the nodule forming or nodule inhabiting bacteria in the nodules is necessary to classify the importance of these organisms and their economic benefit to agricultural production. This study also underlines the importance of using PCR methods to gain valuable insights into the ecological behaviour of Rhizobium inoculants and nodule inhabiting organisms.
98

Potencial de linhagens de feijão preto oriundas da população "Ouro Negro&#8223; x "Meia Noite&#8223; / Potencial lines of black been coming from "Ouro Negro&#8223; x "Meia Noite&#8223;

Oliveira, Bruna Mendes de 16 February 2012 (has links)
Made available in DSpace on 2015-03-26T13:42:25Z (GMT). No. of bitstreams: 1 texto completo.pdf: 855108 bytes, checksum: 3c702cbb17b7f4560fc290e26b49cf0f (MD5) Previous issue date: 2012-02-16 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The main objective of this work was to identify lines of black beans with the potential to make future tests of Value for Cultivation and Use (VCU) in Minas Gerais. Thus, 93 lines of the population "Ouro Negro" x "Meia Noite", conducted by bulk method, bulk method with selection for grain aspect and SSD, with 31 lines in each method, were evaluated. The experiments were conducted at the experimental area, of the Universidade Federal de Viçosa, Department of Plant Science, in Coimbra, Minas Gerais, during the winter season (sowing in Jun/Jul) and dry season (sowing in Feb/Mar) of 2009 and 2010. We used a randomized block design with three repetitions and plots of two 2-meters long lines. In all the experiments were evaluated yield, plant architecture, grain aspect and hundred grain weight. The cooking time was measured with the seeds harvested in the winter season of 2010. The assessment of reaction to races 65, 73, 81, 87 and 89 of Colletotrichum lindemuthianum was done under controlled conditions, with inoculation. Individual and compound analyses of variance were carried out for yield, plant architecture, grain aspect and hundred grain weight. The selection of the most promising lines was based on resistance to anthracnose, in cooking time and in the selection index of the genotype-ideotype, modified to take into consideration all evaluation environments. In addition, analysis of adaptability and stability of the centroid method with additional points, were performed. Two lines were promising, even outperform the "Ouro Negro&#8223; in some important attributes. These lines are candidates for future tests of VCU in Minas Gerais. The selection index of the genotype-ideotype showed efficient for the selection of lines and, with minor modifications, can be used to cover the several evaluation environments. Considering the origin of the lines in methods of conductions the segregating population, we can imply that the bulk with selection for grain aspect was better than the bulk and SSD methods when it comes to the potential of the population for the extraction of superior lines of beans. / O principal objetivo deste trabalho foi identificar linhagens de feijão preto com potencial para compor os futuros ensaios de Valor de Cultivo e Uso (VCU) em Minas Gerais. Para isso, foram avaliadas 93 linhagens da população "Ouro Negro&#8223; x "Meia Noite&#8223;, conduzidas pelos métodos bulk, bulk com seleção para aspecto de grãos e SSD, com 31 linhagens em cada método. Os experimentos foram conduzidos na Estação Experimental do Departamento de Fitotecnia da Universidade Federal de Viçosa, em Coimbra, Minas Gerais, nas safras da seca e do inverno de 2009 e de 2010. Utilizouse o delineamento em blocos casualizados com três repetições e parcelas de duas linhas de dois metros. Em todos os experimentos avaliaram-se a produtividade de grãos, a arquitetura de planta, o aspecto de grãos e a massa de 100 grãos. O tempo de cocção foi avaliado com os grãos colhidos no experimento do inverno de 2010. A avaliação da reação às raças 65, 73, 81, 87 e 89 de Colletotrichum lindemuthianum foi feita em condições controladas, com inoculação. Foram realizadas as análises de variância individuais e conjunta da produtividade de grãos, arquitetura de plantas, aspecto de grãos e massa de 100 grãos. A seleção das linhagens mais promissoras baseou-se na resistência à antracnose, no tempo de cocção e no índice de seleção da distância genótipo-ideótipo, modificado de modo a levar em consideração todos os ambientes de avaliação. Além disso, foi realizada análise de adaptabilidade e estabilidade pelo método do centróide com pontos adicionais. Duas linhagens mostraram-se promissoras, inclusive superando a cultivar Ouro Negro em alguns atributos importantes. Essas linhagens são candidatas a futuros ensaios de VCU em Minas Gerais. O índice de seleção da distância genótipo-ideótipo mostrou-se promissor para fins de seleção de linhagens e, com pequenas modificações, pode ser utilizado de modo a abranger os vários ambientes de avaliação. Considerando a origem das linhagens em termos de condução da população segregante, pode-se inferir que o método bulk com seleção para aspecto de grãos foi superior aos métodos bulk e SSD quando se trata do potencial da população para extração de linhagens superiores de feijão.
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Aplicação de fertilizantes foliares em culturas anuais /

Peruchi, Maximilian. January 2006 (has links)
Orientador: Salatiér Buzetti / Banca: Orivaldo Arf / Banca: Helder Barbosa Paulino / Resumo: A adubação foliar ainda é uma prática pouco estudada, tanto no que concerne às concentrações, épocas de aplicação e produtos utilizados. O interesse pelo uso do fornecimento de nutrientes minerais através das partes aéreas da plantas cultivadas vem aumentando extraordinariamente, não só nos países mais adiantados do mundo, como também no Brasil, especialmente nos últimos anos. O trabalho teve como objetivo investigar os efeitos da aplicação, via foliar, de B e de Zn em culturas anuais (algodão, arroz, feijão, milho, soja e trigo). A importância do trabalho está no sentido de se obter respostas sobre a aplicação dos produtos atualmente recomendados para as devidas culturas sem o estudo experimental de sua eficiência ou de possíveis danos que possam provocar às culturas, e conseqüentemente auxiliar o agricultor na prática deste manejo. Foi utilizado o delineamento em blocos casualizados e os tratamentos se constituíram pela variação de fontes dos nutrientes boro e zinco aplicados via foliar. Foram avaliados o teor foliar dos macro e micronutrientes, com exceção do cloro e do molibdênio, os componentes de produção e a produtividade das culturas. De acordo com os resultados pode-se concluir que: (a) a aplicação de boro e zinco via foliar, nas culturas do feijão, trigo e algodão, não aumentaram os teores foliares desses elementos, (b) os teores de boro e zinco foliar, na cultura do arroz, foram aumentados quando da aplicação destes nutrientes, (c) a aplicação de zinco via foliar, aumentou o teor foliar desse nutriente nas culturas do milho e da soja, (d) os tratamentos não promoveram efeitos significativos nos componentes de produção e na produtividade das culturas, (e) não se recomendaria a aplicação foliar desses fertilizantes nas culturas estudadas. / Abstract: The leaf fertilization is still a not very studied practice, so much to concentrations, application times and used products. The interest for supplying nutrients through the leaf of cultivated plants comes increasing extraordinarily, not only in the advanced countries of the world, but also in Brazil, especially in last years. The work had as objective to investigate the effects of the application, through leaf, of nutrients in annual crops (cotton, rice, common bean, corn, soybean and wheat). The importance this study is to obtain response about the application of products recommended for those crops without experimental study of its efficiency or possible damages that can provoke to the crops, and consequently to help farmers in the practice of this management. The experimental design was blocks casualizados and the treatments were constituted by sources of boron and zinc applied through leaf. Were appraised the leaf content of macro and micronutrients, except for the chlorine and molybdenum, the production components and productivity of the crops. The results showed: (a) the B and Zn application, in common bean, wheat and cotton crops, did not increase the leaf content those elements, (b) B and zinc leaf content, on rice, were increased when of the application of these nutrients, (c) the leaf application of zinc increased the leaf content this nutrient on corn and soybean, (d) the treatments did not promote significant effects in production components and productivity of the crops, (e) would not be recommended the leaf application those fertilizers on crops studied. / Mestre
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Mapeamento de locos de resistência ao crestamento bacteriano comum do feijoeiro (Phaseolus vulgaris L.) / Genetic mapping of common bacterial blight resistance loci in common bean (Phaseolus vulgaris L.)

Passos, Ana Laura Pereira 26 April 2016 (has links)
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No. of bitstreams: 2 Dissertação - Ana Laura Pereira Passos - 2016.pdf: 6140952 bytes, checksum: 715de51ee1d8b3b7ffd295f5d7121216 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-04-26 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / The common bean (Phaseolus vulgaris) is grown in Brazil in various locations, soil and climatic conditions. The diseases are among the leading causes of losses in productivity of this legume, and the common bacterial blight (CBB) is the most important bacterioses that affects the culture. The resistance of CBB in common bean is a complex quantitative trait that results from the interaction of several genes. Genetic maps are tools that optimize the search for loci associated with this type of feature, and the most commonly used molecular markers available for this type of study are the SNPs (Single Nucleotide Polymorphism). In this sense, this study aimed to: (i) develop a robust genetic map for common bean using SNP markers and the RIL (Recombinant Inbreed Lines) mapping population derived from Ruda × AND 277; (ii) characterize this RIL population and their parents about the reaction to common bacterial blight in field and greenhouse; and (iii) identifying genomic regions (major genes and/or QTL) that control the bacterial blight in this population. We used 393 individuals of the Ruda × AND 277 RIL population, evaluated for reaction to CBB in two field trials in Ponta Grossa - PR, in the rain growing season of 2012 and 2014 and in an inoculation test at the greenhouse, in Santo Antônio de Goiás - GO. The population was genotyped with 5,398 SNP markers and mapping was performed using the R-OneMap and MapDisto programs. Statistical analyzes were performed in the Genes program, and the Scott-Knott method was used for averages groupingin R platform. The QTL analysis was conducted in QTLCartographer program. Using the chi-square test (1:1), 2,062 markers were selected for mapping. Three genetic maps with high strengt, saturation and resolution were built. Statistical analysis showed that there is genetic variability for the CBB resistance in the population of RILs. The QTL analysis identified 10 QTLs linked to resistance of CBB in the Ruda × AND 277 RIL mapping population, in the chromosomes PV01, PV02, Pv07, Pv09 and PV11, based on results from evaluations carried out in the field and greenhouse. The maps constructed for this population have high strength and resolution and may be used for future work on integrative mapping. The statistical analysis evidenced the quantitative character of resistance to CBB in common bean and showed that the parent Rudá has the CBB resistance alleles. It is expected that the markers linked to these QTLs identified can be used in future studies of marker assisted selection. / O feijoeiro-comum (Phaseolus vulgaris) é cultivado no Brasil em vários locais e diversas condições edafoclimáticas. As doenças estão entre as principais causas de prejuízos na produtividade dessa leguminosa, sendo o crestamento bacteriano comum (CBC) a principal bacteriose que afeta essa cultura. A resistência ao CBC no feijoeiro-comum é uma característica complexa, quantitativa, que resulta da interação de vários genes. Os mapas Genéticos são ferramentas que otimizam a busca de locos associados a esse tipo de característica, e os marcadores moleculares mais utilizados disponíveis para esse tipo de estudo são os SNPs (Single Nucleotide Polymorphism). Neste sentido, o presente trabalho teve como objetivos: (i) construir um mapa genético robusto para o feijoeiro-comum, utilizando marcadores SNP e a população de RILs (Recombinant Inbred Lines, ou linhagens endogâmicas recombinantes) derivada do cruzamento Rudá × AND 277; (ii) caracterizar esta população de RILs e seus genitores quanto à reação ao crestamento bacteriano comum, em campo e em casa de vegetação; e (iii) identificar regiões genômicas (genes de efeito principal e/ou QTLs) que controlam a reação ao crestamento bacteriano comum nesta população. Foram utilizados 393 indivíduos da população de RILs Rudá × AND 277, avaliados quanto à reação ao CBC em dois ensaios de campo em Ponta Grossa – PR, nas águas de 2012 e 2014, e em um ensaio de inoculação em casa de vegetação, em Santo Antônio de Goiás - GO. A população foi genotipada com 5.398 marcadores SNP e o mapeamento das RILs foi realizado utilizando os programas R-OneMap e MapDisto. As análises estatísticas foram realizadas no programa Genes, sendo o agrupamento de médias de Scott-knott realizado na plataforma R. A análise de QTL foi realizada no programa QTLCartographer. Por meio do teste de quiquadrado (1:1) foram selecionados 2.062 marcadores para o mapeamento. Foram construídos três mapas genéticos com elevada robustez, saturação e resolução. As análises estatísticas evidenciaram que há variabilidade genética para a característica de resistência ao CBC na população de RILs. A análise de QTL identificou 10 QTLs ligados à resistência ao CBC na população de RILs Rudá × AND 277 nos cromossomos Pv01, Pv02, Pv07, Pv09 e PV11 com base em dados obtidos a partir de avaliações em campo e casa de vegetação. Os mapas construídos para essa população apresentam elevada robustez e resolução e poderão ser utilizados para futuros trabalhos de mapeamento integrativo. As análises estatísticas evidenciaram o caráter quantitativo da resistência ao CBC em feijoeiro-comum e mostraram que o genitor Rudá possui alelos de resistência ao CBC. Espera-se que os marcadores ligados a esses QTLs identificados possam ser utilizados em futuros trabalhos de seleção assistida por marcadores.

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