Efeitos de restos culturais de milho no desenvolvimento inicial de cafeeiros

Abstract

Coffee crop planted to areas previously planted to corn have experienced negative effects on seedlings development, probably due to allelochemicals left in the soil by corn plants. With the objective of identifying the effects of corn straws on the initial growth and development of coffee seedlings, one greenhouse experiment was established at the Federal University of Lavras (UFLA), Lavras, MG, Brazil. The treatments were constituted by four coffee cultivars planted to pots filled with a mixture of field soil and five corn hybrid dried straws, harvested from field at flowering stage and incorporated at 8 t ha-1. Coffee seedlings growth parameters were measured at 7, 30, 60, and 90 days after planting (DAP). The GNZ 2004 corn hybrid straw promoted 18,76% increase in coffee seedlings leaf area at 90 DAP when compared with control without straw. Chlorophyll content and stem dry matter of Catuaí coffee cultivar were inhibited by GNZ 2005 corn hybrid, however GNZ 2004 promoted increase in these parameters of Topázio cultivar. Straw incorporation of GNZ 2004 and P30K75 corn hybrids showed increase in roots dry matter accumulation of coffee seedlings at 90 DAP.