Effect of Different Weed Management Practices on Weed Growth, Yield and Economics of Direct Seeded Rice in Eastern Dry Zone of Karnataka

摘要

Field experiments were conducted at Zonal Agricultural Research Station, Gandhi Krishi Vignana Kendra, University of Agricultural Sciences, Bangalore during rabi 2020 and summer 2021 coming under eastern dry zone of Karnataka to study the efficiency of different herbicides and allelochemicals for weed management in direct seeded rice. The experiment consisted of 12 treatments replicated thrice in RCBD design. Among various herbicide treatments, significantly lowest total weed density and dry weight was recorded with Bispyribac sodium 10 SC @40 g a.i. ha~(-1) as post emergence (17.3 no. m~(-2) and 5.1 g m~(-2), respectively) and found on par with Bensulfuron methyl + pretilachlor 6.6 G @660 g a.i. ha~(-1) as pre emergence (19.3 no. nr2 and 6.9 g m~(-2), respectively). Significantly higher paddy grain and straw yield was recorded with Bispyribac sodium 10 SC @ 40 g a.i. ha~(-1) as post emergence (4987 and 6844 kg ha~(-1), respectively) followed by Bensulfuron methyl + pretilachlor 6.6 G @ 660 g a.i.ha~(-1) as pre emergence (4866 and 6716 kg ha~(-1), respectively) and it was on par with hand weeding at 20 and 40 DAS (5139 and 6960 kg ha~(-1), respectively). Lowest grain and straw yield was recorded in unweeded control (688 and 1485 kg ha~(-1), respectively). Application of Bispyribac sodium 10 SC @ 40 g a.i. ha~(-1) as post emergence has recorded higher net returns (Rs.54581 ha~(-1)) with B:Cratio of 2.61.