Cropping successions on the control of the vegetation and soil seed bank of the weed Annoni-2 Grass (Eragrostis plana Nees)

Abstract

The objective was to study the technical efficiency of cropping successions systems to control the vegetation and soil seed bank of the weed Annoni-2 grass in an invaded native grassland, at Estação Experimental Terras Baixas/ Embrapa Clima Temperado, Capão do Leão, RS, Brazil. Two cropping cycles were carried out including the successions of soybeans, forage sorghum or grain sorghum over summer, with black oat during winter. The pre-emergent herbicides metolachlor (soybeans) and atrazine (grain and forage sorghum) were used. At the end of the second cycle, Pensacola Bahiagrass was sown together with black oat in autumn. The experimental design was blocks at random with six replications. The cropping successions showed the same efficiency at controlling the vegetation of Annoni-2 grass and its soil seed bank since the first cropping cycle. The Annoni-2 grass soil seed bank control was better achieved after the second cropping succession of summer crops plus black oat.