Weed management in kharif rice in new alluvial zone of West Bengal

Abstract

A field experiment was carried out during the Kharif season of two consecutive years 2015 and 2016 at Instructional Farm, Jaguli, Bidhan Chandra Krishi Viswavidyalaya, Nadia, West Bengal with the focal objective to assess the effect of different weed control measures on yield of transplanted kharif rice, IET 4786. Experiment having 3 replications was conducted in Randomized Block Design with nine treatments, namely, T1- Pendimethalin 30% EC + Pyrazosulfuron ethyl 10 % WP @ 675 + 15 g a.i, T2- Pendimethalin 30% EC + Pyrazosulfuron ethyl 10 % WP @ 900 + 200 g a.i, T3- Pendimethalin 30% EC + Pyrazosulfuron ethyl 10 % WP @ 1125 + 25 g a.i, T4- Pendimethalin 30% EC @ 1500 g a.i, T5- Pyrazosulfuron ethyl 10 % WP @ 15 g a.i, T6- Pyrazosulfuron ethyl 10 % WP @ 20 g a.i, T7- Metsulfuron methyl 10 % + Chlorimuron ethyl 10 % WP @ 4 g a.i, T8- Hand weeding and T9- Weedy check. Significant variations were observed on the mixed weed flora as well as on performance of rice under the different herbicidal treatments.Pendimethalin 30% EC + Pyrazosulfuron ethyl 10% WP @ 1125+25 g a.i) was found to be the most effective recording the lowest weed population and weed dry weight with the highest weed control efficiency (83.5% in 2015 and 79.8 % in 2016) and the highest number of panicles m-2 (215.1 in 2015 and 231 in 2016), number of filled grains panicle-1 (85.39 in 2015 and 115.47 in 2016) and grain yield of rice (3.60 t/ha in 2015 and 5.30 t/ha in 2016). The lowest grain yield(2.20 t/ha in 2015 and 3.40 t/ha in 2016) and the highest weed density were observed in weedy check plots.