Vol. 11 No. SP
Efficacy of herbicides on weed management in wet season transplanted rice
Author(s): K. CHARAN TEJA, B. DUARY AND M. K. BHOWMIK
Abstract: A field experiment was conducted during the kharif (wet) season of 2013 at farmer\'s field of village Benuria, Sriniketan, Birbhum, West Bengal with rice variety \'Swarna\' (MTU 7029) to study the effect of bensulfuron-methyl + pretilachlor and other herbicides on weed growth and productivity of wet season transplanted rice. The experiment comprising of twelve treatments was laid out in a randomized block design with three replications. From the experimental findings it revealed that rice was infested with the three categories of weeds viz. grassy, broadleaved and sedges. Cynodon dactylon, among the grasses; Fimbristylis miliacea, among the sedges and Ludwigia parviflora, among the broadleaved weeds were predominant throughout the cropping period. The experimental field was dominated by broadleaved weeds. Among the herbicides application of bensulfuron-methyl 0.6%+ pretilachlor 6% at 60+600 g ha-1 at 3 DAT registered the lower number as well as dry weight of grassy, broadleaved, sedge and total weeds at 45 DAT but it was at par with bensulfuron-methyl 0.6%+ pretilachlor 6% at 90 + 900 and 120 +1200 g ha-1 at 3 DAT. Metsulfuron methyl + chlorimuron-ethyl (Almix) + azimsulfuron at 4+35 g ha-1 at 15 DAT was also quite effective in controlling broad spectrum weeds. Lower values of weed density, total weed dry weight and weed index, higher values yield attributes and yield of rice, weed control efficiency, net return as well as return per rupee invested were registered with application of bensulfuron-methyl 0.6%+ pretilachlor 6% at 60 + 600 g ha-1 at 3 DAT and metsulfuron methyl + chlorimuron- ethyl (Almix) + azimsulfuron at 4+35 g ha-1 at 15 DAT. The loss of grain yield of rice due to weed infestation was to the tune of 40%. Application of bensulfuron-methyl 0.6%+ pretilachlor 6% at 60+600 g ha-1 at 3 DAT or metsulfuron methyl + chlorimuron- ethyl (Almix) + azimsulfuron at 4 + 35 g ha-1 at 15 DAT appeared to be the most promising for managing weeds, obtaining higher yield and net return of transplanted kharif (wet) rice in the lateritic belt of West Bengal.
Download Full Article: Click Here