Crop rotation and physical and chemical properties of a Red Latosol in the Cerrado under conventional tillage and recent no-tillage.

摘要

The purpose of this work was to evaluate the yields and physical and chemical soil properties of a dystropherric Red Latosol (Oxisol) in the third year of a crop rotation that included green manures, with soyabean or maize (summer) and common bean (winter) crops. The following green manure species were used: velvet bean, millet, sunnhemp, pigeon pea, cultivated under conventional tillage and recently adopted no-tillage. The experiment was conducted in Selviria, Mato Grosso do Sul, Brazil, in the 1999/2000 growing season. The experiment was arranged in a randomized complete block design with split-split plots and four replications. After three years of crop rotation under no-tillage the soil physical properties had degraded mostly in the surface layer. On the other hand, in this system and soil layer, there was an increment in organic matter content and pH. There also was obtained greater maize grain yield under not-tillage as compared to the conventional tillage. The yield of common bean was higher when it was cultivated following the maize crop under conventional tillage and after soyabean under no-tillage.