Bioefficacy, Phytotoxicity and Economics of Post-emergence Herbicides in Moth Bean (Vigna aconitifolia) in Hot Arid Regions

Weed infestation is the major cause of yield loss to Kharif pulses in arid regions. Post-emergenceherbicide application is a promising weed management option for pulses in these areas. Therefore, the current study wasaimed to find an effective and economic post-emergence herbicide molecule for weed control in moth bean.

A field experiment was conducted during 2017-2019 with different herbicides, hand weeding, weed-free and unweededs in Kharif mung bean in a randomized complete block design with three replications.

Among the herbicide treatments, post-emergence application of propaquizafop + imazethapyr @ 125 g a.i. ha^-1 being statistically at par with clodinafop-propargyl + sodium acifluorfen @ 312.5 g a.i. ha^-1 and hand weeding recorded the highest reduction in total weed dry matter (73.9%), highest weed control efficiency (73.8%)and lowest weed persistence index (1.03) compared to the unweeded. The reduction in seed yield in unweeded compared to weed-free and hand weeding was 50.8% and 42.1%, respectively. As the imazethapyr-containing herbicides caused crop phytotoxicity, significantly higher crop dry weight (513 g m^-2), seed yield (5.53 q ha^-1), stover yield(18.0 q ha^-1), grossreturns and net benefits of moth bean were recorded with clodinafop-propargyl + sodium acifluorfen(312.5 g a.i. ha^-1) over other herbicide treatments. Clodinafop-propargyl + sodium acifluorfen (@312.5 g a.i. ha^-1) registered theminimum value of weed index (20)and highest values of herbicide efficiency index (3.9) and crop resistance index (4.70).