Effect of Brown Manuring and Herbicide Application on Weed Parameters on Aerobic Rice under Varying Planting Geometry

A Field Experiment was conducted at Main Rice Research Centre, Navsari Agricultural University, Navsari during kharif 2021. The experiment was carried out in randomized block design with factorial concept with three replication. The results revealed that density of grasses, sedges, broad-leaved weeds and thus total weed density were significantly higher in 40 cm line sowing at 20 DAS and 40 DAS. Weed dry weight at 60 DAS and at harvest was also significantly higher with 40 cm line sowing. Hand weeding twice at 20 and 40 DAS recorded no weed at 20 DAS and at 40 DAS and was closely followed by Pendimethalin 750 g a.i. ha-1 (PE) + Bispyribac sodium 40 g ha-1 at 30 DAS. Considerably lower weed dry weight at 60 DAS and at harvest was recorded with Hand weeding twice at 20 and 40 DAS which was at par with Pendimethalin 750 g a.i. ha-1 (PE) + Bispyribac sodium 40 g ha-1 at 30 DAS. Numerically higher weed control efficiency at 60 DAS and at harvest and lower weed index was also recorded by Hand weeding twice at 20 and 40 DAS followed by Pendimethalin 750 g a.i. ha-1 (PE) + Bispyribac sodium 40 g ha-1 at 30 DAS. Weed smothering efficiency was found to be higher with Pendimethalin 750 g a.i. ha-1 (PE) + Brown Manuring at 60 DAS and at harvest.