No description available.

Orientador: Cláudio Cavariani / Banca: José de Barros França Neto / Banca: Leila Martins / Resumo: A cultura da soja, em razão de sua importância no agronegócio mundial, é alvo de inúmeras pesquisas no campo fitotécnico na busca por novas informações para elevação da produtividade. O vigor é um dos principais atributos da qualidade fisiológica das sementes a ser considerado na implantação de uma lavoura, pela influência que pode ter no crescimento e no rendimento das plantas. A pesquisa teve como objetivo avaliar o desempenho de plantas de soja e a qualidade das sementes produzidas em diferentes densidades populacionais, em função do nível de vigor das sementes utilizadas. O experimento foi conduzido em duas etapas. A primeira constituiu da fase de campo, mediante delineamento em bloco ao acaso, com quatro repetições, em esquema fatorial 3x3 (densidades populacionais de 7, 12 e 17 pl.m-1 e níveis de vigor das sementes alto, médio e baixo), empregando-se três cultivares de soja. Foram avaliados a população inicial, a data do florescimento, o ciclo, a altura média das plantas e da inserção da primeira vagem, os números médio de vagens por planta e de sementes por vagem, a população final de plantas, em relação à inicial, e a produção de sementes. A segunda etapa foi realizada no laboratório e constou da avaliação das características qualitativas das sementes de soja produzidas na etapa anterior. Foi evidente o efeito do vigor das sementes na emergência de plântulas em campo, sendo superior quando oriundas das sementes de alto vigor. A elevação da densidade de plantas de soja na linha ressalta, positivamente, efeitos dos níveis de vigor no desenvolvimento das plantas. O vigor das sementes e a densidade de plantas na linha têm influencia na produção de soja; elevações de 8% e 6% na produção foram observadas em plantas originadas de sementes com vigor médio e alto, em relação às... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Due to the importance of soybean in the world agribusiness, this crop has been the subject of innumerous research studies, looking for management techniques to increase production per area. The vigor is one of the main seed physiological quality characters that has to be considered in the crop establishment, because it can influence the plant growth and final production. This study aimed to evaluate the performance of soybean plants and the quality of seeds produced in different population densities, depending on the level of vigor of the seed sown. The experiment was conducted in two stages. The first one was conducted at the field, in randomized block design, with four replications, in a factorial 3x3 design (densities of 7, 12 and 17 pl.m-1 and levels of seed vigor, high, medium and low), using three soybean cultivars. The following parameters were: initial population, flowering cycle, average height of plants and first pod; average number of pods per plant and seeds per pod; final population of plants (in relation to the initial population); and seed yield. In the second stage, conducted in the laboratory, the quality of the produced seed was evaluated. The effect of seed vigor on seedling emergence in the field was evident, being higher when derived from the seeds of high vigor. The high density of soybean plants in the row highlights positively the effects of vigor levels upon plants development. Seed vigor and plant density on the line have influence on soybean production; increases of 8% and 6% in seed yield were observed in plants from seeds with medium and high vigor, compared to those coming from low vigor. Seed vigor and plant density on the line do not affect the physiological quality of the produced seeds / Mestre

Made available in DSpace on 2014-06-11T19:22:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-03-01Bitstream added on 2014-06-13T18:48:45Z : No. of bitstreams: 1 rossi_rf_me_botfca.pdf: 365226 bytes, checksum: 61d4bb5c47783421434379c08c1d49bb (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A cultura da soja, em razão de sua importância no agronegócio mundial, é alvo de inúmeras pesquisas no campo fitotécnico na busca por novas informações para elevação da produtividade. O vigor é um dos principais atributos da qualidade fisiológica das sementes a ser considerado na implantação de uma lavoura, pela influência que pode ter no crescimento e no rendimento das plantas. A pesquisa teve como objetivo avaliar o desempenho de plantas de soja e a qualidade das sementes produzidas em diferentes densidades populacionais, em função do nível de vigor das sementes utilizadas. O experimento foi conduzido em duas etapas. A primeira constituiu da fase de campo, mediante delineamento em bloco ao acaso, com quatro repetições, em esquema fatorial 3x3 (densidades populacionais de 7, 12 e 17 pl.m-1 e níveis de vigor das sementes alto, médio e baixo), empregando-se três cultivares de soja. Foram avaliados a população inicial, a data do florescimento, o ciclo, a altura média das plantas e da inserção da primeira vagem, os números médio de vagens por planta e de sementes por vagem, a população final de plantas, em relação à inicial, e a produção de sementes. A segunda etapa foi realizada no laboratório e constou da avaliação das características qualitativas das sementes de soja produzidas na etapa anterior. Foi evidente o efeito do vigor das sementes na emergência de plântulas em campo, sendo superior quando oriundas das sementes de alto vigor. A elevação da densidade de plantas de soja na linha ressalta, positivamente, efeitos dos níveis de vigor no desenvolvimento das plantas. O vigor das sementes e a densidade de plantas na linha têm influencia na produção de soja; elevações de 8% e 6% na produção foram observadas em plantas originadas de sementes com vigor médio e alto, em relação às... / Due to the importance of soybean in the world agribusiness, this crop has been the subject of innumerous research studies, looking for management techniques to increase production per area. The vigor is one of the main seed physiological quality characters that has to be considered in the crop establishment, because it can influence the plant growth and final production. This study aimed to evaluate the performance of soybean plants and the quality of seeds produced in different population densities, depending on the level of vigor of the seed sown. The experiment was conducted in two stages. The first one was conducted at the field, in randomized block design, with four replications, in a factorial 3x3 design (densities of 7, 12 and 17 pl.m-1 and levels of seed vigor, high, medium and low), using three soybean cultivars. The following parameters were: initial population, flowering cycle, average height of plants and first pod; average number of pods per plant and seeds per pod; final population of plants (in relation to the initial population); and seed yield. In the second stage, conducted in the laboratory, the quality of the produced seed was evaluated. The effect of seed vigor on seedling emergence in the field was evident, being higher when derived from the seeds of high vigor. The high density of soybean plants in the row highlights positively the effects of vigor levels upon plants development. Seed vigor and plant density on the line have influence on soybean production; increases of 8% and 6% in seed yield were observed in plants from seeds with medium and high vigor, compared to those coming from low vigor. Seed vigor and plant density on the line do not affect the physiological quality of the produced seeds

The ogu-INRA cytoplasmic male sterility (CMS) system is the global leader for the development of high quality hybrid canola and high erucic acid rapeseed (HEAR) cultivars of oilseed rape (Brassica napus L.). The largest challenge for plant breeders using this system is the development of high quality restorer lines (R-lines) due to tight linkage of the radish (Raphanus sativus L.) derived restorer gene PPR-B and elevated seed glucosinolate concentration. The purpose of this study was to identify improved quality restorer lines for hybrid cultivar development through both field studies and molecular marker development. In the first study 67 R-lines of different genetic backgrounds were screened over the course of two growing seasons and lines with significantly reduced glucosinolate concentration were identified. In the second study a new sequence characterized amplified region (SCAR) marker was successfully developed for the rapid screening of selections for the ogu-INRA CMS restorer gene PPR-B.

The ogu-INRA cytoplasmic male sterility (CMS) system is the global leader for the development of high quality hybrid canola and high erucic acid rapeseed (HEAR) cultivars of oilseed rape (Brassica napus L.). The largest challenge for plant breeders using this system is the development of high quality restorer lines (R-lines) due to tight linkage of the radish (Raphanus sativus L.) derived restorer gene PPR-B and elevated seed glucosinolate concentration. The purpose of this study was to identify improved quality restorer lines for hybrid cultivar development through both field studies and molecular marker development. In the first study 67 R-lines of different genetic backgrounds were screened over the course of two growing seasons and lines with significantly reduced glucosinolate concentration were identified. In the second study a new sequence characterized amplified region (SCAR) marker was successfully developed for the rapid screening of selections for the ogu-INRA CMS restorer gene PPR-B.

No description available.

No description available.

Chickpea production in the short growing season of the Canadian Prairies is still a challenging task due to excessive and continuous vegetative growth which often results in severe yield and quality reduction. This study examined the effects of three plant growth retardants (PGR), Chlormequat Chloride (CCC), Prohexadione Calcium and Trinexapac Ethyl applied during flowering stage on vegetative growth, seed quality, yield and crop maturity of the Kabuli chickpea cultivar CDC Frontier. Field experiments were conducted at Brooks and Bow Island in southern Alberta in the 2010 and 2011 growing seasons. Four concentrations of each PGR were applied at 10, 20 and 30 days after flowering (DAF) stages. During the 2010 growing season the crop experienced above average moist and cooler temperature conditions. In contrast, later half of the 2011 growing season was above average dry and hot. None of the three PGR tested in this study had a significant effect on plant height at 30 days after treatments or on above ground biomass plant-1 at harvest. Application of PGR had no significant effects on the number of seeds m-2, except at the Brooks rain-fed site in 2011 where the PGR treatment applied at 10 and 20 DAF increased the number of seeds m-2 at harvest. An increase of 1000-seed weight of marketable seeds was obtained with Prohexadione Calcium and Trinexapac Ethyl applications at Bow Island, but the effects were not consistent across sites and years. Results suggested that the effect of PGR on 1000-seed weight of marketable seeds mainly depended upon the growing environment and the type of PGR. In general, PGR applications reduced the total and marketable seed yields. Application of Prohexadione Calcium and Trinexapac Ethyl at the Bow Island site delayed crop maturity in 2011. In contrast, the application of CCC at 6000 mg L-1 at 20 DAF accelerated crop maturity at the Brooks irrigated site in 2011. In addition to this main study, the potential effects of Pyraclostrobin and Prothioconazole fungicides on the activities of the three PGR were compared by a separate experiment conducted at the Brooks irrigated site in 2011. The results of that study revealed that there were no significant differences in the effects of PGR on chickpea vegetative growth, seed yield parameters and maturity when they were applied as a mixture with either Pyraclostrobin or Prothioconazole fungicide. In summary, results revealed that PGR applied during flowering stage were not effective on controlling vegetative growth of chickpea and did not improve seed yield and crop maturity. Their effects on yield-related traits were highly inconsistent. Thus, it can be concluded that the application of PGR is not a reliable agronomic option to handle the production issues associated with continues vegetative growth at the late reproductive stage of the chickpea cultivar CDC Frontier under the western Canadian growing conditions.

Made available in DSpace on 2014-06-11T19:26:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-01-28Bitstream added on 2014-06-13T18:54:59Z : No. of bitstreams: 1 santacruzoviedo_vr_me_botfca.pdf: 253923 bytes, checksum: d788e43f5154fa351b3082b8b6f18339 (MD5) / Foram conduzidos dois experimentos na FCA/UNESP, objetivando avaliar a depressão causada por endogamia com sucessivas gerações de autofecundação em uma população de pepino do tipo japonês. No primeiro experimento foram avaliadas características de produção de frutos imaturos no período de 21/08/2002 à 29/11/2002 em ambiente protegido. No segundo experimento foram avaliadas características de produção e qualidade de sementes no período de 12/03/2003 à 13/06/2003 em condições de campo. A partir do intercruzamento entre plantas do híbrido Natsu suzumi foi obtida a geração F2, considerada como população S0. Obtiveram-se progênies S1, S2, S3, S4 e S5, através de autofecundações sucessivas pelo método do SSD ('Single Seed Descent'). Ao partir da mistura ao acaso de sementes de progênies com igual número de autofecundações sucessivas foram obtidas cinco populações denominadas de população S1 a população S5. Foram sete tratamentos (híbrido Natsu suzumi, populações S0 a S5) e o delineamento experimental foi em blocos ao acaso, com seis e quatro repetições no primeiro e segundo experimento, respectivamente e cinco plantas por parcela nos dois experimentos. No primeiro experimento (frutos imaturos) foram avaliados, número de folhas, comprimento da haste principal, número e massa de frutos, total e comercial, número de nós e porcentagem de brotações. No segundo experimento (frutos maduros) avaliaram-se características relacionadas com produção (número e massa de sementes por planta e por fruto) e qualidade de sementes (teste padrão de germinação, primeira contagem de sementes, índice de velocidade de germinação, massa de 100 sementes). Foram realizadas as análises de variância para cada característica, e as médias dos tratamentos foram comparadas pelo teste de Tukey (%). Também foram realizados análises de variância apenas com as seis... / Two experiments were set up at FCA/UNESP. The objective of this work was to evaluate the inbreeding depression with successive generations of self pollination in a cucumber Japanese population. It was studied one population F2 obtained from a commercial hybrid (Natsu suzumi) considered as S0 population. In the first experiment were appraised characteristics of production of immature fruits in the period of 21/08/2002 to 29/11/2002 in protected cultivation. In the second experiment were appraised seed production and quality in the period of 12/03/2003 to 13/06/2003 in open field conditions. It was obtained progenies S1, S2, S3, S4 and S5 through the 'Single Seed Descent' methodology. It was used randomized blocks with seven treatments (different generations of self pollination - S0 to S5 and the hybrid Natsu suzumi) six and four replicates in the first and second experiment and five plants per plot in both. In the first experiment (immature fruits) were evaluated number of leaves, length of the main stem, number and weight of fruits, total and commercial, number of nodes and vines percentage. In the second experiment (mature fruit) characteristic related with production were evaluated (number and weight of seeds per plant and per fruit) and quality of seeds (germination test, first counted of seeds, index of germination speed and weight of 100 seeds). The variance analyses were accomplished each characteristic and the averages of the treatments were compared by the test of Tukey (%). Also accomplished just with the six inbreed generations to evaluate the possible inbreeding depression (without including the commercial hybrid). In the comparison among the population differences were not observed for the characteristics appraised showing there were not production loss for inbreeding in this population. However, for the characteristics length of the main stem, number of total fruit, weight of seeds per fruit and seed number per fruit the commercial.

Doctor of Philosophy / Department of Plant Pathology / Christopher R. Little / Fusarium spp. are among the most important pathogen groups on soybeans. However, information regarding this genus on soybean seeds in the state of Kansas remains underexplored. Therefore, the goal of this study was to characterize the identity, frequency, and pathogenicity of soybean seedborne Fusarium spp. in the state of Kansas. For the identification and frequency of seedborne Fusarium spp., culture-dependent (i.e. semi-selective medium) and -independent (i.e. DNA metabarcoding) approaches were used. Also, information regarding the pathogenicity of the most common seedborne Fusarium spp. from soybeans was assessed to better understand their role as soybean pathogens. Overall, eleven Fusarium spp. were identified in this study. Semi-selective media showed that approximately 33% of soybean seed samples were infected with Fusarium spp. Moreover, Fusarium spp. were isolated from seed sampled from 80% of the locations in Kansas. Furthermore, a low incidence of Fusarium spp. was observed within infected seed samples and averaged 2%. Nine Fusarium spp. were found in soybean seeds using the culture-dependent approach. Fusarium semitectum was the most frequent, followed by F. proliferatum and F. verticillioides. Fusarium acuminatum, F. equiseti, F. fujikuroi, F. graminearum, F. oxysporum, and F. thapsinum were found in lower frequencies among naturally infected seeds. DNA metabarcoding experiments showed that Fusarium spp. are more frequent in soybean seeds than previously known. All asymptomatic soybean seeds analyzed, using Illumina MiSeq platform, showed the presence of the genus Fusarium including two pathogenic species, F. proliferatum and F. thapsinum. Fusarium acuminatum, F. merismoides, F. solani, F. semitectum, and Fusarium sp. were also identified using the culture-independent approach. Preliminary results also showed that F. proliferatum and F. thapsinum were observed in all three major soybean seed tissues: seed coat, cotyledons, and the embryo axis. Depending on the soybean genotype, inoculum potential and aggressiveness, F. proliferatum, F. graminearum, F. fujikuroi, F. oxysporum, F. semitectum, F. thapsinum, and F. verticillioides were pathogenic to soybean and negatively affect soybean seed quality, at different levels, in controlled conditions. Moreover, F. equiseti and F. acuminatum did not cause significant damage to soybean seeds and seedlings. Understanding seedborne Fusarium spp. and their influence on soybean seed and seedling diseases is critical for the development of effective disease control strategies, especially regarding early detection of pathogenic strains in seeds (i.e., seed health testing), ensuring the crop productivity, quality, and safety.