Effect of chemical weed management on weed growth and yield of summer greengram in red and lateritic soil of West Bengal

A field experiment was conducted at Nildiganta Baganbari Farm, Bariadihi village near Santiniketan, Birbhum, West Bengal during the summer season of 2024 to study the efficacy of different herbicides against complex weed flora and impact on weed growth, yield and profitability of summer green gram. Eight treatments viz, pre-emergence application (PE)of pendimethalin @ 0.75 kg ha-1 at 1 day after sowing (DAS), post-emergence application (PoE) of imazethapyr @ 50 g ha-1 at 20 DAS, quizalofop-p-ethyl @ 50g ha-1 PoE at 20 DAS, fenoxaprop-p-ethyl @ 60 ml ha-1 PoE at 25 DAS, propaquizafop @ 60 ml ha-1 PoE at 20 DAS, ready mix sodium acifluorfen + clodinafop-propargyl @ 0.245 kg ha-1 PoE at 25 DAS, two hand weeding at 15 and 30 DAS and unweeded control were assigned under randomized block design replicated thrice. The dominant weed species infesting the greengram were Digitaria sanguinalis, Echinochloa colona, among grasses, Amaranthus viridis among broad leaved and Cyperus iria, Cyperus rotundus among sedges. Experimental results revealed that sodium acifluorfen + clodinafop-propargyl @ 245ml ha-1recordedthe lowest weed count and biomass of all categories of weed. The weed control efficiency was found to be 100% in hand weeding at 15 and 30 DAS. But among the herbicides, sodium acifluorfen + clodinafop-propargyl @ 245 ml ha-1exhibited the highest efficacy in controlling weeds with a total weed control efficiency of 86.1% and 72.6% at 30 DAS and 45 DAS, respectively. Sodium acifluorfen + clodinafop-propargyl @ 245 ml ha-1also recorded higher values of plant growth and yield attributes, which in turn resulted in highest seed yield (746 kg ha-1) and economic return. Application of sodium acifluorfen + clodinafop-propargyl @ 245 ml ha-1 was found to be effective for management of diverse weed flora and higher yield of greengram in lateritic soil of West Bengal.