Vol. 14 No. 2
Weed management in blackgram [Vigna mungo (L.) Hepper] through sole and combined application of pre- and post-emergence herbicides
Author(s): G. SINGH, H. K. VIRK AND V. KHANNA
Abstract: Field experiments were conducted at the research farm of the Punjab Agricultural University, Ludhiana, Punjab, India during kharif 2011 and 2012 to study the effect of herbicides on weeds, growth, symbiotic traits and grain yield of blackgram (cv. Mash 338). The experiment was laid out in a randomized complete block design with three replications having fourteen treatments comprising of weedy check, different doses of pre-emergence and postemergence herbicides, two hand weedings and weed free. Pre-emergence application of pendimethalin 30 EC + imazethapyr 2 EC (pre-mix) @ 0.75 kg ha-1 and 1.0 kg ha-1 significantly reduced the dry weight of weeds (84.9 and 85.3%, respectively) at harvest than weedy check and also provided highest weed control efficiency. However, application of post-emergence herbicides quizalofop ethyl 5 EC @ 37.5 kg ha-1 and fenoxaprop ethyl 10 EC @ 50 g ha-1 did not control the weeds effectively. Number and dry weight of nodules plant-1 were recorded lowest in postemergence application of quizalofop ethyl 5 EC @ 37.5 g ha-1. Amongst herbicide treatments, pre-emergence application of pendimethalin 30 EC + imazethapyr 2 EC (pre-mix) @ 1.0 and 0.75 kg ha-1 recorded the highest grain yield, gross returns, net returns and B:C ratio.