Studies on Chemical Weed Management Practices on Growth and Yield of Blackgram [Vigna mungo (L.)]

An investigation was carried out at Zonal Agricultural Research Station, Kalaburagi, University of Agricultural Sciences, Raichur during kharif 2021-22 entitled studies on chemical weed management practices on growth and yield of blackgram [Vigna mungo (L.)]. The experiment was laid out in randomized complete block design with nine treatments and three replications. Among all the treatments, hand weeing at 25-30 DAS, recorded significantly lower weed density, higher weed control efficiency that favoured higher growth and yield parameters. Whereas, among the chemical weed management practices, application of sodium acifluorfen 16.5% + clodinafop propargyl 8% EC @ 1.0 kg a.i. ha-1 at 20-25 DAS as post emergent recorded significantly lower weed population (2.71/0.25 m2), lower weed dry weight (1.53/0.25 m2) and higher weed control efficiency (90.31 %) compared to other chemical weed management treatments. The treatment sodium acifluorfen 16.5% + clodinafop propargyl 8% EC @ 1.0 kg a.i. ha-1 at 20-25 DAS as post emergent also recorded significantly higher growth parameters viz., plant height (40.18 CM), number of branches (9.18), and dry matter production at harvest (23.50 g plant-1) and yield components viz., number of pods plant-1 (46.69 ), number of seeds pod-1 (7.89), 100 seed weight (4.7 g), seed yield (1059 kg ha-1) compared to other treatments. Significantly higher net returns (Rs.48,406) were recorded in hand weeding at 25-30 DAS and intercultivation at 45 DAS, which was on par with application of sodium acifluorfen 16.5% + clodinafop propargyl 8% EC @ 1.0 kg a.i. ha-1 at 20-25 DAS (Rs.45,066 ha-1). The higher benefit cost ratio was recorded with application of sodium acifluorfen 16.5% + clodinafop propargyl 8% EC @ 1.0 kg a.i. ha-1 at 20-25 DAS (3.08) followed by hand weeding at 25-30 DAS and intercultivation at 45 DAS.