Bio-efficacy on tank-mixed propaquizafop and imazethapyr against weeds in soybean

Intensive use of agro-chemicals coupled with congenial edaphic and weather conditions during Kharif season aggravate the weed menace, resulting into low yields of soybean. The experiment was conducted on the agricultural farm at Jawaharlal Nehru Krishi Vishwa Vidyalaya at Jabalpur in 2011–12. The rampant weed species identified in the experimental field was monocot weeds Cyperus rotundus (25.8 and 23.6%) followed by Echinochloa colona (23.1 and 23.3%) and Commelina benghalensis (15.6 and 17.8%). Beside these dicot weeds Eclipta alba (19.1 and 20.3%), and Alternanthera philoxeroides (16.4 and 14.9%) were also found in soybean ecosystem at 45 DAS and harvest stage, respectively. The weed menace was minimum under weed free treatment. Among the propaquizafop treatments, activity of propaquizafop at lowest dose 62.5 g/ha and highest dose 75 g/ha as post emergence was not well marked against most of weeds (broad-leaved) but imazethapyr applied at 50, 75, 100 g/ha controlled broad-leaved and grassy leaved weeds. Among herbicidal treatments, combined application of propaquizafop + imazethapyr as post-emergence 75 + 100 g/ha was most effective to reduced most of weed flora.