Effect of establishment methods and weed management practices on the growth and yield of direct seeded rice (Oryza sativa L.)

The field experiment was conducted at Agronomy Research Farm of Narendra Deva University of Agriculture and Technology, Kumarganj, Faizabad (U.P.) during Kharif season of 2015 and 2016. The experiment was laid out in split-plot design with three replications taking four establishment methods viz., Dry Seeding, Seeding through Drum Seeder (Wet) and Broadcasting (Wet) under puddled condition in main plot, and eight weed management practices viz. Bispyribac-Na @ 25g/ha at 25DAS (3-4 Leaf stage of rice crop), Pendimethaline @100g/ha at 0-2DAS fbBispyribac-Na@25g/ha at 25DAS (3-4 Leaf stage of rice crop), Oxadiargyl @100g/ha 0-2DASfb Bispyribac-Na@25g/ha at 25DAS (3-4 Leaf stage of rice crop), Pretilachlore @ 750g/ha at 0-2DASfbAlmix @ 4 g/ha at 25DAS (3-4 Leaf stage of rice crop), Pyrazosulfuran @ 20 g/ha at 0-2DAS fb ethoxysulfuran @18.75 g/ha at 25DAS (3-4 Leaf stage of rice crop), Manual Weeding (20,40,60 DAS), Weed free and weedy check were kept in sub-plot. The observations were recorded on weeds and on crop at successive stages of crop growth during both the years. The major weed flora recorded in the experiment were E.crusgalli E. colona and P. maximum of grassy, Commelina benghalensis L. and Eclipta alba of broad leaved group and Cyperus spp. of Sedges group. However, grassy weeds were dominant over other weeds species. Density and dry weight of total weeds, growth, and yield attributes as well as yield of grain and straw, N uptake by weeds and crop were significantly affected due to different treatments. Lower values of weed density and dry weight, N uptake and higher values of growth attributes, N uptake by crop, yield and yield attributes were recorded significantly due to manual weeding thrice (20, 40, 60 DAS), and Pretilachlore @ 750g/ha at 0-2DASfbAlmix @ 4 g/ha at 25DAS (3-4 Leaf stage of rice crop) being at par at all characters during both the years. However, weedy check treatment recorded significantly lower values of the entire growth characters yield and yields attributes at all the stages over rest of the weed control treatments. Both of the DSR (wet) drum seeding and broadcasting being at par recorded significantly lower values of weed density, weed dry weight and higher values of growth and yield attributes, grain and straw yield over dry seeding methods during both the years. On the basis of two years experimentation, it may be concluded that higher values of grain yield may be obtained due drum seeding of establishment of rice along with integrated method of using weed management by Pretilachlore @ 750g/ha at 0-2DASfbAlmix @ 4 g/ha at 25DAS (3-4 Leaf stage of rice crop), while, DSR (wet) drum seeding and broadcasting showed the same response However, direct seeding of rice through drum along with Pretilachlore @ 750g/ha at 0-2DASfbAlmix @ 4 g/ha at 25DAS (3-4 Leaf stage of rice crop) proved superior (BCR values of Rs 2.12 per ha) over other methods of rice establishment under puddled condition.