Efeito da adubação nitrogenada em cobertura sobre o conteúdo de molibdênio da semente de feijão-caupi cultivado em solos coesos de baixa fertilidade natural

• Ano de defesa: 2022
• Autor(a) principal: Barbosa, Werlen Araújo
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual do Maranhão; Brasil; Campus São Luis Centro de Ciências Agrárias – CCA; BIODIVERSIDADE E BIOTECNOLOGIA-REDE BIONORTE; UEMA
• Palavras-chave em Português: Nutrição molíbdica; Produtividade; Enriquecimento de sementes; Nitrogênio; Vigna unguiculata; Feijão-Caupi; Molibdênio; Agroecologia
• Link de acesso: https://repositorio.uema.br/jspui/handle/123456789/2898

In the literature, there are few studies that have evaluated the effects of nitrogen (N) on coverage on molybdenum (Mo) content in cowpea seeds. Our hypothesis is that N fertilization in top dressing increases the Mo content in cowpea seeds. A trial was conducted in São Luís, Maranhão, between May and August 2019. The treatments were arranged in a 4 x 2 factorial scheme: doses of Mo applied to the foliage (0, 50, 250 or 500 g ha-1) and N doses in top dressing (0 or 50 kg ha-1), in a block design randomized, with four replications. The Mo source was sodium molybdate and the N source was urea. At planting, all plots received 350 kg ha-1 of the 4-14-8 formula. It was used the cultivar BRS Guariba. The average productivity of the trial was 627±172 kg ha-1, and the plants that not receiving N or Mo presented 2.42±0.68 nodules per plant. There was interaction significant (P < 0.010) between doses of Mo and doses of N in productivity and Mo content in the seed. Without application of N in top dressing, productivity increased by 306 kg ha-1 (without Mo) to 729 kg ha-1 (with 250 g ha-1 of Mo). With application of N in coverage, there was no significant difference between the productivity obtained with doses between 50 and 500 g ha-1 of Mo, but plants sprayed with 50 g ha-1 of Mo produced 58% more grains than those without received Mo. Without application of N in top dressing, the Mo content in the seed increased until the dose of 500 g ha-1 of Mo and reached 5.9 μg seed-1 of Mo. With application of N in coverage, the Mo content in the seed increased up to the dose of 250 g ha-1 of Mo and reached 5.1 μg seed- 1 of Mo. Our results suggest that the application of N in top dressing increases the N content Mo in the seed when cowpea plants are sprayed with doses of up to 250 g ha- 1 of Mo.