Influência da época de semeadura na severidade de doenças foliares e na produtividade do milho safrinha

ABSTRACT In the main grain producing areas, corn has been grown in two harvest seasons, summer corn (first corn crop) and winter corn (second corn crop). With the corn crop throughout the year in the field, a green bridge was created, favoring the development and the permanence of pests and diseases. The severity of diseases can limit crop development and compromise productivity. The objective of this study was to verify the influence of the time of the sowing season on foliar disease severity and yield of second corn crop in northern Paraná State in two consecutive harvest seasons, 2015 and 2016. Cercospora zeae-maydis, Pantoea annanatis and Exserohilum turcicun were the main diseases observed in the two consecutive years in the northern region of the state of Paraná. Sowings up to 10/03 showed greater Puccinia polysora and Pantoea annanatis severities, while Exserohilum turcicun was more pronounced in sowings after 10/03. For Cercospora zeae-maydis, the sowing time did not show effective influence. Higher productive rates were achieved when sowing was performed early.