Interação entre sistemas de manejo e de controle de plantas daninhas em pós-emergência afetando o desenvolvimento e a produtividade do milho

Abstract

This work aimed to evaluate the interaction between burndown methods and systems of post-emergence weed control in corn, hybrid AG 9010, under no-tillage, in areas with expressive soil green cover. Ten treatments in a factorial scheme (3 x 3) + 1 were evaluated. Main factors were composed by three burndown systems (desiccation immediately before sowing; desiccation 7 days prior to crop sowing and anticipated desiccation, composed by two burndown herbicide applications, the first 24 days prior to sowing and the second immediately before sowing), three post-emergence weed control systems (no control, manual weeding and herbicide application) and an additional treatment constituted by an absolute check (no burndown and no post-emergence weed control). Burndown either at sowing date or 7 days prior to sowing decreased grain yield. Anticipated burndown provided not only a reduced flux of weed emergence during early crop development but also crop yield gains from 880.5 to 1555.5 kg ha-1..