IMPACT OF VARIOUS RATES OF PENDIMETHALIN HERBICIDE ON WEED CONTROL, SEED YIELD AND ECONOMIC RETURNS IN MUNGBEAN UNDER RAINFED CONDITIONS

Various rates of herbicide (pendimethalin) (2, 3 and 4 l/ha) including hand weeding were tried for weed control, seed yield and economic return of mungbean at Arid Zone Research Institute, D.I. Khan, Pakistan during the year 2006 and 2007. Hand weeding produced higher yield (1092 and 743.3 kg/ha) comparaed to control (631 and 518.8 kg/ha). Among herbicide rates the lowest rate (2 l/ha) yielded 1090 and 706.6 kg per hectare during the year 2006 and 2007, respectively. The dominant weed recorded was Convolvulus arvensis during both the years. All herbicidal rates including hand weeding significantly controlled the weeds. But generally hand weeding offered the most effective control by 64 and 76 percent but at par with herbicide rate of 2 liter per hectare (54 and 75% weed control). However, hand weeding was highly labour intensive which required 30 to 32 labours per hectare for weeding and considered to be impracticable by local farmers. During 2006, herbicide dose of 2 l/ha increased the plant height (4.3 cm), pods per plant (24%), grains per pod (5%), 1000-seed weight (16%) and seed yield (73%) over control and appeared at par with hand weeding treatment in main contributing parameters of seed yield. During 2007, same dose of herbicide was also at par with hand weeding treatment which increased the plant height (19%), pods per plant (90%), grains per pod (13%), 1000-seed weight (4%) and seed yield (36%) over control. Herbicide application @ 2 l/ha also had the highest value/cost ratio (19.3) among the treatments, ranging from 9.6 to 19.3 and might be profitable approach for achieving maximum production of mungbean under rainfed conditions.