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Made available in DSpace on 2021-06-25T22:23:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-12-18 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Molybdenum (Mo) is an essential micronutrient involved in several biochemical reactions that influence biological nitrogen fixation (BNF). Plants are known to require less molybdenum. The objective of this study was to evaluate the effect of Mo foliar application on four soybean cultivars (Glycine max [L.] Merrill) and their physiological qualities, crude protein, and lipid content. The experimental design was completely randomized, in a 4 x 3 factorial arrangement, with four replicates. Three Mo application rates (0, 400, and 800 g ha(-1)) were used for the AS 3730 IPRO, Bonus IPRO, Desafio RR, and BMX Potencia RR cultivars during their R3 and R5 reproductive stages. The Mo concentration, nutritional parameters (crude protein [CP] and lipids), and physiological quality (electrical conductivity, vigor, aging seed, and germination) of the seeds were then evaluated. The cultivars x Mo application rate interaction had no significant effect. There was an observed increase in Mo content with molybdic leaf fertilization. The BMX Bonus IPRO and BMX Potencia RR cultivars had the best response, with increased Mo concentration within the seeds. The Mo rates did not influence CP and lipids. However, the soybean cultivar x Mo application rate interaction significantly affected the germination percentage and percentage of accelerated aging seeds. Univ Estadual Londrina, Dept Crop Sci, Londrina, Parana, Brazil Sao Paulo State Univ, Dept Crop Sci, Ilha Solteira, Brazil Embrapa Soja, Dept Soil Fertil & Plant Nutr, Londrina, Parana, Brazil Sao Paulo State Univ, Dept Crop Sci, Ilha Solteira, Brazil

A soja (Glycine max (L.) Merrill) é o principal produto agrícola de exportação do país e estudos têm mostrado que a nutrição adequada das plantas é fundamental para manter a qualidade das sementes e alcançar altas produtividades. A carência de boro (B) afeta a produção da soja, diminuindo o número de sementes por vagens e número de nós por planta, não havendo especificações de doses adequadas as diversas condições edafoclimáticas do Brasil. Neste trabalho, objetivou-se avaliar o efeito de fontes de boro aplicadas ao solo em diferentes doses na qualidade das sementes e nos componentes de produção da soja. O delineamento experimental utilizado foi o inteiramente casualizado em esquema fatorial 2 × 5, com duas fontes de boro [ácido bórico (18% de B) e ulexita (12% de B)], aplicadas em cinco doses (0, 2, 4, 8 e 16 mg kg-1), com quatro repetições. A cultivar BRS 1003 IPRO de crescimento indeterminado foi utilizada. Exceto a relação NGV/NVV, a produção de MSPA, NGV, NVV e peso de 100 grãos foram influenciados pelos tratamentos com interação fontes × doses de B. Houve incremento dos teores de B disponível no solo e folha diagnósticos com o aumento das doses de B com os maiores teores na fonte H3BO3 em relação a ulexita. A produção máxima de grãos não apresentou efeito das fontes e foi obtida com a aplicação de 4 kg ha-1 para aplicação em sistema plantio direto. Apesar do teor de B disponível no solo ter apresentado correlação significativa com o teor foliar, a equação forneceu capacidade preditiva relativamente baixa em relação a estimativa da PG. o envelhecimento acelerado (EA) e porcentagem de germinação não sofrem influência de fontes e doses de B, enquanto o peso de 100 sementes, comprimento radicular de plântulas (CR) e protrusão radicular (PR) apresentaram interação fontes × doses e estão intimamente relacionados a disponibilidade do nutriente no solo, o que não foi observado para o comprimento da parte área da planta (CPA). O VR apresenta relação significativa com as doses de B e está diretamente correlaciona com a PG. No caso do teor de lignina no tegumento (LT), independente da fonte de B, houve relação inversa das doses em relação ao teor de LT, indicando possível efeito negativo no processo de armazenamento e longevidade da semente. Soybean (Glycine max (L.) Merrill) is the country's main agricultural export and studies have shown that adequate plant nutrition is essential to maintain seed quality and achieve high yields. The boron (B) lack affects soybean yield, decreasing the number of seeds per pod and number of nodes per plant, there are no specifications of adequate doses for the different edaphoclimatic conditions in Brazil. The objective of this work was to evaluate the effect of boron sources applied to the soil at different doses on seed quality and yield components. The experimental design used was completely randomized in a 2 × 5 factorial scheme, with two B sources [boric acid, H3BO3 (18% of B) and ulexite (12% of B)], applied in five rates (0, 2, 4, 8, and 16 mg kg-1), with four replicates. The indeterminate growth BRS 1003 IPRO cultivar was used. Except for the NGV/NVV ratio, the yield of shoot dry weight (SDW), NGP, NPP, and weight of 100 grains were influenced by treatments with interaction sources × rates. There was an increase in the levels of available B in the soil and diagnostic leaf with increasing doses of B with the highest contents in the H3BO3 source in relation to ulexite. The maximum GY did not show an effect of the sources and was obtained with the 4 kg ha-1 for application in no-till system. Although the available B in the soil showed a significant correlation with the foliar content, the equation provided a relatively low predictive capacity in relation to the GY estimate. the accelerated aging (EA) and germination percentage are not influenced by sources and doses of B, while the weight of 100 seeds, seedling root length (CR) and root protrusion (PR) showed sources × rates interaction and are closely related to availability of the nutrient in the soil, which was not observed for the length of the plant part area. RV has a significant relationship with B rates and is directly correlated with GY. In the case of the lignin content in the tegument (LT), regardless of the B source, there was an inverse relationship between the rates in relation to the LT content, indicating a possible negative effect on the storage process and seed longevity.