Influence of Type and Amount of Straw Cover on Weed Emergence

Abstract

This research was undertaken during 2003–2004 growing season to evaluate the {effects of type [forage sorghum “hybrid Cober Exp” (Sorghum bicolor × Sorghum} sudanense), forage millet (Pennisetum americanum “var. BN2”), finger millet {(Eleusine coracana), and St Lucia grass (Brachiaria brizantha)] and amount of} {straw cover (5.5 and 3.0 t ha}−1) upon the emergence of Bidens pilosa, Chamaesyce {spp., Amaranthus spp., and Commelina benghalensis, under field conditions of the} {Brazilian Cerrado, in the region of Uberlândia—MG. The control consisted} {additional treatment lacking the straw cover. Emergence of weed depended on the} {type and amount of straw cover, as well as the weed species. The lowest number} {of B. pilosa seedlings was found in the presence of forage sorghum straw;} {Chamaesyce spp. in the lack of straw; Amaranthus spp. in the presence of higher} {amount of forage sorghum and forage millet, and lower amounts of forage millet} {and Finger Millet. All the types and amounts of straw reduced the emergency of} {C. benghalensis, except at the lowest level of St Lucia grass and the lack of straw.