Desempenho agrônomico de soja em função da sucessão de culturas em sistema de plantio direto

Abstract

With the objective of evaluating the effect of crop rotation or succession on soybeans agronomic performance in no tillage system, an experiment was carried out in a distrophic Red Latosol, at the Núcleo Experimental de Ciências Agrárias da Universidade Federal de Mato Grosso do Sul, in the county of Dourados-MS. The experimental procedure was a randomized blocks design with nine treatments and four replications. The plots had 36 meters of length and 11 meters of width (396 m2), where were mechanically sawed 26 lines of soybeans, at intervals of 0,45 meters between lines. The treatments were composed of nine systems of crop succession: system 1: corn/vetch/corn/vetch/soybeans; system 2: cotton/oat/cotton/sorghum/soybeans; System 3: soybean/wheat/soybeans/corn/millet/soybeans; system 4: corn/grazing turnip/corn/sorghum/soybeans; system 5: corn/oat/corn/beans/millet/soybeans; system 6: rice/grazing turnip/rice/oat/soybeans; system 7: rice/sorghum/rice/beans/millet/soybeans; system 8: cotton/wheat/cotton/wheat/soybeans and system 9: cotton/grazing turnip/cotton/oat/soybeans. The dry matter of the aerial part of the soybean plants in full flowering stadium, plants height and first pod insertion, number of pods per plant, the productivity and the 100 grains mass, were evaluated. It was concluded that the crop rotation or crops succession was not influenced by the plant height, pods insertion and number of pods per plant. On the other hand, the rotation systems of rice/sorghum/rice/beans/millet/soybean and soybeans/wheat/soybeans/corn/millet/soybean, provided the soybeans the higher grains yield.