Vol. 8, Issue 9, Part J (2024)

A field study was conducted at the Agricultural Farm, Institute of Agriculture, Visva-Bharati, West Bengal, during the monsoon season 2023 (kharif) to explore the effect of metsulfuron methyl on optimized weed management in transplanted rice. The experiment was carried out using a randomized block design (RBD) with eleven treatments, which were replicated thrice. The treatments included, four different doses of encapsulated and commercial metsulfuron methyl viz., 2 g a.i ha^-1, 3 g a.i ha^-1, 4 g a.i ha^-1 and 5 g a.i ha^-1. These treatments were compared with the farmers practice of hand weeding twice at 20 and 40 days after transplanting. The weed free check and unweeded control treatments were maintained for evaluating the weed control efficiency of commercial and encapsulated metsulfuron methyl. Both commercial and encapsulated formulations of metsulfuron methyl were applied as pre emergence on five days after transplanting and the solvent evaporation method was utilized for encapsulating metsulfuron methyl. The findings revealed that, among the herbicidal treatments, pre emergence application of encapsulated metsulfuron methyl at 5 g a.i ha^-1 resulted in lower weed density (16.00 m^-2), reduced weed dry weight (3.99 g m^-2), greater weed control efficiency (97.27%), higher weed control index (97.35%), maximum grain yield (5816 kg ha^-1) and a modest weed index (2.44%) compared to others. However, this was closely followed and statistically at par with encapsulated metsulfuron methyl 4 g a.i ha^-1. Notably, the application of encapsulated metsulfuron methyl at 2 g a.i ha^-1 resulted significantly lower weed density (41.33 m^-2), reduced weed dry weight (10.99 g m^-2), superior weed control efficiency (92.95%), enhanced weed control index (92.70%), substantial grain yield (5257 kg ha^-1) and a reduced weed index (11.81%) than recommended dose of commercial metsulfuron methyl 4 g a.i ha^-1. Considering the ecological balance, environmental sustainability and shortage of skilled agriculture labour, this study concludes that, pre emergence application of encapsulated metsulfuron methyl at 2 g a.i ha^-1 on five days after transplanting is ideal for effective weed control, enhanced productivity and profitability of transplanted rice.