Effect of Propaquizafop and Imazethapyr Mixture on Weed Dynamics, Growth, Yield and Economics of Soybean [Glycine max (L.) Merill]

The results of field experiments conducted during Kharif seasons of 2013 and 2014 to adjudge the efficacy of propaquizafop and imazethapyr mixture (tank mixed) to combat weeds and impact the growth and yield of soybean are reported. The treatments consisted of four doses of propaquizafop + imazethapyr mixture (47 + 70, 50 + 75, 53 + 80 and 56 + 85g ha-1), sole application of propaquizafop (75 g ha-1) and imazethapyr (100 g ha-1) as early post-emergence and pendimethalin (1000 g ha-1) as pre-emergence, hand weeding(HW) twice at 20 and 40 d after sowing(DAS)and weedy check. The dry matter accumulation for all the recorded weed flora was found the lowest in combined application of herbicides rather than their sole application, being higher under propaquizafop + imazethapyr mixture applied at 53 + 80 g ha-1 or higher rate (56 + 85 g ha-1). Higher values of growth parameters (plant height, branches plant-1, nodules plant-1), yield attributes (pods plant-1, seeds pod-1, seed index), yield and B: C ratio were recorded under propaquizafop + imazethapyr mixture applied at 56 + 85 g ha-1 followed by 53 + 80 g ha-1 which were comparable to hand weeding twice at 20 and 40 DAS.