Weed competition studies were done during Kharif seasons of 1989 and 1990 at the research station, Barkachha, Mirzapur of Danaras Hindu University. Eleusine indica, Digiaria ciliaris, Cyperus spp. were the major weeds associated with pigeonpea/sesame intercropping system. The maximum relative growth of weeds was between 15 to 45 days after sowing. Weed competition, reduced the yield of pigeonpea and sesame by 43.1% and 43.2% respectively. The magnitude of yiold reduction of piaeonpea was maximum between 30 and 45 days after sowing and that of sesame was maximum between 15 and 30 days after sowing.
