Screening of Weed Competitive Cultivars of Summer Green-gram in Lateritic Soil of West Bengal

A field experiment was conducted in two consecutive summer seasons of 2008 and 2009 at the Institute of Agriculture, Visva-Bharati, Sriniketan, West Bengal to screen out the weed competitive Green-gram cultivars. Experimental plots were infested with grassy, broadleaved and sedge weeds. Digitaria sanguinalis among grasses, Croton bonplandianum among broad leaved and Cyperus rotundus among sedges were most predominant throughout crop season. Losses in seed yield of green-gram due to weed infestation ranged from 7 to 37%. Among the cultivars, the plots of ‘WBM 34-1-1’, ‘WBM 04-5’ and ‘PDM 54’ registered lower number as well as dry weight of grasses, broadleaved, sedges and total weeds at 45 days after sowing (DAS) under both weedy and one hand weeding situations. These cultivars also recorded higher values of yield attributes and seed yields. Yield components viz. number of pods/plant, seeds/pod, test weight as well as seed yield were significantly reduced in weedy situation, compared with one hand weeding at 30 DAS in all the cultivars excepting ‘PDM 54’ and ‘WBM 04-5’, where no significant reduction due to weed competition was recorded, indicating higher weed competitive abilities of both the cultivars. The cultivars ‘WBM 34-1-1’, ‘WBM 04-5’ and ‘PDM 54’ appeared to be promising towards suppressing weeds and producing higher seed yields in lateritic soil of West Bengal.

Competitive crop cultivars are an important cost-effective tool for the management of weeds causing yield reduction to the extent of 7–37% in summer greengram.

‘PDM 54’, ‘WBM 04-5’ and ‘WBM 34-1-1’ were identified as promising weed competitive greengram cultivars.