Palhadas e doses de nitrogênio no plantio direto do feijoeiro

Abstract

Aiming at verifying different straws and nitrogen levels effects on common bean no-till, a study was carried out at Federal University of Lavras (Lavras, Minas Gerais, Brazil). The experiment design utilized was randomized blocks and four replications in split plot arrangement, with five straws (millet, jack bean, dwarf guandu, millet + jack bean and millet + dwarf guandu) in the plots and four nitrogen levels (0, 50, 100 and 150 kg ha-1) in sub-plots. The initial and final stands, plant height, grain yield and its primary compounds were evaluated. Millet straw provided greatest dry bean stand. Jack bean single and intercrops provided the largest hundred-grain weight. Nitrogen rate provided negative linear effect for initial stand, and positive effect on hundred-grain weight. Grain number per pod increased by 106 kg ha-1 N rate and had low reduction after that. There were significant interactions between straws and N rate for plant height, pod per plant and grain yield. Millet + jack bean provided greatest plant height at 115 kg ha-1 N rate. Pod number per plant had linear and positive effect on all straw types and the highest values were observed in intercropping combinations in the maximum N rate. The best grain yield was obtained under millet + jack bean in the largest N rate.