Plantio direto na palha de leguminosas como estratégia para melhorar a eficiência de uso de nutrientes em milho QPM

Abstract

The low nutrient use efficiency and undernourishment of rural population are the greatest challenges for socioeconomic development in humid tropic. The aims of this study were: 1) to evaluate the effect of no-till in combination with residues of leguminous on the N and K use efficiency; 2) to study the agronomic performance of QPM maize BR 473 in that system. The maize variety BR 473 was grown in a alley cropping system and the treatments consisted of different legume biomass combinations with and without mineral fertilizer, and two controls in discovered soil: 1) S+L+NK - clitoria + leucaena + 40-40 kg ha-1 of N-K; 2) A+L+NK - acacia + leucaena + 40-40 kg ha-1 of N-K; 3) S+G+NK - clitoria + gliricidia + 40-40 kg ha-1 of N-K; 4) A+G+NK - acacia + gliricidia + 40-40 kg ha-1 of N-K; 5) S+L - clitoria + leucaena; 6) A+L - acacia + leucaena; 7) S+G - clitoria + gliricidia; 8) A+G - acacia + gliricidia; 9) NK - 40-40 kg ha-1 of N-K in discovered soil; 10) Control – without biomass and without mineral fertilization. The results showed that no-till farming with residues of leguminous improves the N and K use efficiency and provides nutrients throughout the crop cycle. However, mineral fertilizer is essential for corn to reach maximum yield. S+L+NK was the best treatment and the QPM variety can improves the economic and nutritional conditions of people