Jefferson Santana da Silva Carneiro

No-Tillage and Phosphate Fertilization Management on Soybean Culture in Brazilian Cerrado

Despite the benefits of no-till practices, soil compaction is a problem that can cause, among other things, mechanical impediment to root growth and less response to soil fertilization. The objective of this study was to evaluate the effect of subsoiling and doses of phosphate fertilization on soybean that have been cultivated over ten years under no-till systems in the Brazilian Cerrado. The experiment consisted of a randomized complete block design in a 2 × 4 factorial arrangement. Two managements in consolidated no-tillage area were considered: with and without subsoiling, along with four levels of phosphate fertilization: 0, 100, 300 and 400 kg ha -1 of P 2 O 5 . The practice of subsoiling in an area with ten years of no-till system provided an increase of 124.38 kg ha -1 in soybean productivity. Soybean plants grown under no-tillage system, with subsoil management, showed better development and pod production. The maximum phosphorus efficiency, with subsoiling, was achieved with the dose of 172 kg ha -1 of P 2 O 5 , yielding 5,693.4 kg ha -1 . In the no-tillage system, the maximum efficiency dose and crop yield were 159 kg ha -1 of P 2 O 5 and 5434.2 kg ha -1 , respectively.

Eficiência de fertilizante fosfatado na cultura da soja no cerrado baiano

Os teores de Fosforo na solucao dos solos da regiao do Cerrado sao geralmente baixos. Objetivou-se avaliar a eficiencia de doses do fertilizante comercial TOP PHOS na adubacao fosfatada para a cultura da soja no Cerrado no oeste baiano. O experimento foi conduzido em delineamento de blocos casualizados, com cinco repeticoes e tres replicatas em cada repeticao. Os cinco tratamentos avaliados foram: T1: Testemunha - 0 kg ha -1 de P 2 O 5 ; T2: 100 kg ha -1 de P 2 O 5 ; T3: 200 kg ha -1 de P 2 O 5 ; T4: 300 kg ha -1 de P 2 O 5 ; e T5: 400 kg ha -1 de P 2 O 5 . Os tratamentos foram obtidos com a aplicacao do fertilizante TOP PHOS ® nas doses de 0; 357,14;714,29; 1071,43 e 1428,57 kg ha -1 . As plantas de soja M-soy 9350 ® respondem a altas doses de P 2 O 5 aplicados em solos do Cerrado no Oeste da Bahia, aumentando sua produtividade em funcao das doses crescentes de P 2 O 5 . Para alcancar a maxima producao da soja com o uso do fertilizante Top Phos deve-se aplicar 86% a mais do fertilizante em relacao a recomendacao convencional considerando o nivel de fertilidade e caracteristicas do solo estudado.