WEED CONTROL EFFICIENCY OF METSULFURON METHYL 20% IN AUS RICE

Abstract

The experiment was conducted in the experimental field of Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka during the period of March to July, 2018 to assess the weed control efficiency of Metsulfuron Methyl 20% in aus rice. BRRI dhan48 was used as the test crop in this experiment. The experiment consisted of two factors: Factor A: Doses of Metsulphuron Methyl 20% (4 doses) as - D 0 = Control i.e. no weedicide, D 1 = Metsulphuron Methyl 20% @ 45 g ha -1 , D 2 = Metsulphuron Methyl 20% @ 52 g ha = Metsulphuron Methyl 20% @ 60 g ha -1 ; Factor B: Time of application (4 times) as - T 1 = Application at 12 DAT, T 2 = Application at 15 DAT, T 3 = Application at 20 DAT

and T 4 = Application at 25 DAT. The two factors experiment was laid out in split-plot design with three replications. Data were recorded on weed control efficiency, yield contributing characters and yield of BRRI dhan48 and statistically significant variation was observed for different doses of Metsulphuron Methyl 20%, time of application and their combined effect. In considering the different doses of Metsulphuron Methyl 20%, the highest weed control efficiency (77.14%) was observed from D 3 and the lowest (23.40%) from D 1 . The longest plant (95.90 cm), the maximum number of effective tillers hill

(11.08), the longest panicle (21.31 cm), the maximum number of filled grains panicle -1 (81.98) and the highest grain yield (5.08 t ha ii -1 -1 and D 3 ) was recorded from D 3 . For time of application, the highest weed control efficiency (67.09%) was found from T 3 and the lowest (15.56%) from T 2 . The longest plant (96.11 cm), the maximum number of effective tillers hill -1 (11.73), the longest panicle (20.63 cm), the maximum number of filled grains panicle -1 (80.38) and the highest grain yield (4.81 t ha -1 ) was observed from T 3 ,. Considering combined effect of different doses of Metsulphuron Methyl 20% and time of application, the interaction of D 3 T 3 (Metsulphuron Methyl 20% @ 60 g ha -1 × application at 20 DAT) gave highest grain yield (5.49 t ha -1 ). This may be attributed to the longest plant (99.81 cm), maximum number of effective tillers hill -1 (12.53), the longest panicle (22.80 cm), maximum number of filled grains panicle (85.27) and heaviest 1000-seed weight (24.86 g) as well as highest weed control efficiency (92.15%) was found in this interaction treatment D 3 T 3 . Considering all Metsulphuron Methyl 20% @ 60 g ha -1 and application at 20 DAT showed the best performance when considered the weed control efficiency, yield contributing characters and yield of BRRI dhan48.