Integrated weed management in cotton in cotton-wheat system

摘要

The field experiment was conducted during the kharif seasons of 1996 and 1997. Cyperus rotundas, Cynodon dactylon, Trianthema monogyna, Cyperus iria and Panicum spp. were the dominant weeds. Out of 10 weed control treatments, when averaged over boththe years, the maximum cotton yield of 1140 kg ha~(-1) was obtained in hand weeding 30 and 60 DAS and was at par with pendimethalin 1 kg ha~(-1) fb hand weeding 30 DAS and alachlor 2 kg ha~(-1) fb hand weeding 30 DAS. Minimum cotton yield of 798 kg ha~(-1) was obtained in weedy check. Cotton is reported to be most sensitive to crop weed competition and the yield loss due to weeds ranges from 30 to 70 percent. Weed competition is one of the important constraints in cotton cultivation. There were many methods adopted for control of weeds in the field and chemical method of weed control has proved to be the best. However, satisfactory control of weeds cannot be achieved by using any one method alone. Pre-emergence application of herbicides would be appropriate for minimizing only the early weed competition and problem of late emerging weeds is more serious (Patil et al, 1997). The present investigation was carried out with a view to find out the optimum dose of herbicides for weed control in cotton andits residual effect on wheat crop.