Effect of pre- and post-emergence herbicides on growth and nutrient uptake of weeds in urdbean (Vigna mungo) crop under Shivalik foothills plains of Jammu

A field study was conducted during the summer seasons of 2015 and 2016 at the Sher-e-Kashmir University of Agricultural Sciences and Technology of Jammu, Chatha, Jammu and Kashmir, to study the effect of pre- and post-emergence application of herbicides on nutrients uptake by weeds and blackgram or urdbean [Vigna mungo(L.) Hepper] crop. A significant reduction in weed density and weed biomass was observed with 2 hoeing. Further, among the herbicidal treatments, imazethapyr + pendimethalin @ 1,000 g/ha as pre-emergence and imazethapyr + imazamox 80 g/ha as post-emergence significantly reduced the weed density and weed biomass. The lowest nutrient depletion by weeds, highest grain and stover yields and nutrient uptake by urdbean crop were recorded with pre- emergence application of imazethapyr + pendimethalin @ 1,000 g/ha. Thus, pre-emergence application of imazethapyr + pendimethalin @ 1,000 g/ha may be used for effective weed-management for achieving the higher seed yield (786 kg/ha and 743 kg/ha) in urdbean crop, as it provided higher net returns of (₹45,205/ha and 41,364/ha) and benefit: cost ratio of (2.56 and 2.29) to resourceful farmers of sub-tropical conditions of Jammu region.