ALLELOPATHIC EFFECT OF CONGRESS GRASS ON WEEDS AND YIELD OF WHEAT

A research trial was conducted at the Agricultural Research Institute, Dera Ismail Khan to investigate the allelopathic effect of congress grass applied alone or in combination with half and full recommended doses of commercial herbicides (Puma Super and Buctril Super) during the year 2010-11. The results revealed that weed control strategies including hand weeding (30 and 60 days after sowing), application of herbicides and use of congress grass water extract significantly controlled weeds over the weedy check. Among the treatments, herbicide Puma Super full recommended dose (625 mL ha^-1) significantly increased leaf area index, leaf area duration, crop growth rate, number of tillers, number of grains spike^-1, 1000-grain weight and grain yield. While, weed density and dry weed biomass were minimum in hand weeding. The findings revealed that, in order to obtain maximum yield of wheat, the plots should be kept weed free by hand weeding throughout the growing season or weeds should be suppressed by application of herbicide like Puma super with recommended dose. It is therefore concluded that herbicides can be used to control weeds in wheat field where labor is expensive.