Timely weed management is important to increase productivity in s longduration crop like pigeonpea. A field study to evaluate the effect of weed management on weed interference, nutrient depletion by weeds and production potential of long duration pigeonpea under irrigated ecosystem was conducted at Agricultural Research Farm, IAS, BHU, Varanasi during 2009-10 and 2010-11. Results revealed that use of imazethapyr @ kg ha-1 followed by (fb) paraquat @ kg ha-1 40 days after sowing (DAS) significantly (P ≤ ) reduced the weed density, total weed density and total weed dry weight being statistically at par with two hand weeding (HWs) at 25 and 50 days after sowing (DAS). Weed control index, weed persistence index and weed index were the highest in weed- free, 2- HWs and imazethapyr applied @ kg ha-1 fb paraquat kg ha-1 . However, weed-free treatment resulted in per cent higher yield attributes like pods plant-1 ( and ), grains pod-1 (34 and ), 1000-grain weight ( and ), grain yield ( and ), gross returns ( and ), net returns ( and ) and benefit-cost ratio ( and ), being significantly higher than weedy check but remained at par with 2-HWs, imazethapyr @ kg ha-1 fb paraquat @ kg ha-1 . The highest nutrient depletion by weeds was recorded in weedy check, whereas, the lowest was in imazethapyr @ kg ha-1 fb paraquat kg ha-1 . | Effect of weed management on weed interference, nutrient depletion by weeds and production potential of long duration pigeonpea (Cajanus cajan L.) under irrigated ecosystem
