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 1/3(rd) 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%.