Impacto do míldio na produtividade da soja no sul de Mato Grosso do Sul, safra 2006/2007

Abstract

Foliar diseases that attacks soybean crop constitutes one of the main limiting crop yields for soybeans. Soybean downy mildew, caused by the oomycota Peronospora manshurica, is one of the diseases of major distribution in all regions of the world where soybean is cultivated. Soybean downy mildew can damage leaves and in some cases pods. This research aimed to evaluated the incidence and severity of downy mildew at field, and its impact on soybean yield. Two experiments were carried out in Dourados-MS, one in Maracaju-MS and another in Ponta Porã-MS, from October, 2006, to March, 2007, where BRS 133, BRS 240 and BRS 245 RR cultivars were cultivated, respectively. Treatments were established as randomized block experimental design, with five replications and four treatments, as following: fenamidona (500 g i.a. L-1), iprovalicarbe (55 g i.a. kg-1) + propinebe (613 g i.a. kg-1), cloridrato de propamocarbe (722 g i.a. L-1), which were applied every two weeks, and a control, without applying of fungicide for downy mildew control. For all treatments, soybean rust (Phakopsora pachyrhizi) was controlled by tebuconazole (150g i.a.ha-1). In the conditions that essays were carried out, it was not detected the effect of the disease on soybean yield. are necessary for elucidating the effect of the disease on soybean yield.