RESPONSE OF WHEAT CROP (TRITICUM AESTIVUM L.) AND ITS WEEDS TO ALLELOPATHIC CROP WATER EXTRACTS IN COMBINATION WITH REDUCED HERBICIDE RATES

A field trial to investigate the response of wheat (Triticum aestivum L.) crop and its weeds to various crop water extracts (sorghum, brassica and sunflower ) in combination with reduced rates of herbicide (Bromoxynil + MCPA 20 + 20 EC) was carried out at Research Area, College of Agriculture, Dera Ghazi Khan. The treatment combinations were the mixture of all three crop water extracts each @ 15 and 18 L ha^-1 combined with 1/2 and 1/3rd dose of Bromoxynil + MCPA. Individual herbicide (Bromoxynil + MCPA) treatments i.e. 1/2, 1/3, full dose and a weedy check were included for comparison. Experiment was laid out in randomized complete block design (RCBD) with 4 replications. An approved wheat cultivar, AS- 2002, was used as experimental material. The data recorded at 70 DAS (days after sowing) showed that water extracts @ 18 L ha^-1 combined with Bromoxynil + MCPA 50 g a.i ha^-1 inhibited total weeds density by 88%, total weeds fresh weight by 90% and total weeds dry biomass by 95% and increased grain yield by 35% over control. Highest marginal rate of return was observed in combination of crop water extracts each @18 La^-1 tank mixed with 50 g a.i ha^-1 Bromoxynil + MCPA with net benefit of Rs. 87117. It can be concluded that by the use of allelopathic crop water extracts herbicides use can be reduced up to 50%.