Weed control in soybean (Glycine max (L.) Merrill) crop with incorporated pre-planting herbicides

Abstract

The present research was carried out for studying the use of herbicides as pre-planting incorporation in soybean. The field research was conducted at "Faculdade de Ciências Agrárias e Veterinárias, Campus de Jaboticabal" on a oxisol containing 2,3% organic matter. The experimental design was the randomized complete blocks, with 12 treatments and 4 repetitions. Each plot had 3 x 5.0 m and 0,60 m apart rows. The treatments with the rates in a.i./ha were as follows: dinitramine + metribuzin at 0.30 + 0.25; 0.50 + 0.25; 0.30 + 0.50; and 0.50 + 0.50; dinitramine + vernolate at 0.30 + 3.0 and 0.50 + 3.0; dinitramine at 0.30 and 0.50; metribuzin at 0.25 and 0.50; vernolate at 3.0; and, control. Weed control effects in each treatment were evaluated by counting the surviving weeds, 40 and 80 days after planting the soybean. The effects of the treatments on the crop were evaluated by counting the stand and by visual evaluation of herbicida injuries. The most important weeds present in the area were: Pennisetum setosum (L.) Rich. Pers.; Acanthospernrum australe (Loef.) O. Kuntze; Borreria sp. and Sida sp. A good control of Pennisetum setosum was obtained with dinitramine alone and dinitramine in mixture. Borreria sp. was controled with dinitramine in mixture at the higher rate. Sida sp. and Acanthospermum australe were not controlled. The statistical analysis didn't show differences in the stand, only the treatment dinitramine + vernolate at 0.30 + 3.0 presenting significant differences.