Herbicide mixtures effect on weed seed bank in direct-seeded rice Raj Sheeja K*,2, Syriac Elizabeth K1,2 2Kerala Agricultural University, Coconut Research Station, Thiruvananthapuram, Kerala, 695 501 1department of Agronomy, College of Agriculture, Vellayani, Thiruvananthapuram, Kerala, 695 522 *Email: sheejakraj70@gmail.com
Abstract To study the effect of post-emergence applied herbicide mixtures, viz. bispyribac-sodium + metamifop and penoxsulam + cyhalofop-butyl on soil weed seed bank, weed seed bank assay were carried out at College of Agriculture Vellayani, Thiruvananthapuram during rainy season 2014 and winter season 2014–15. Weed seed bank assay results revealed a significant reduction in the emergence of sedges, broad-leaved weeds (BLW) and grasses from the soil treated with herbicide mixtures compared to individual application of bispyribac-sodium at 25 g/ha and penoxsulam at 22.5 g/ha. The results also revealed that penoxsulam + cyhalofop-butyl was more effective in reducing the weed seed bank than bispyribac sodium + metamifop. The higher doses of penoxsulam + cyhalofop-butyl (135, 130 and 125 g/ha) were found to be more effective than its lower dose of 120 g/ha. Among the tested doses of bipyribac-sodium + metamifop, its higher doses (90 and 80 g/ha) performed better than lower doses (60 and 70 g/ha) in reducing the soil weed seed bank. Hence, postemergence application of penoxsulam + cyhalofop-butyl either at 125 or 130 or 135 g/ha or bispyribac-sodium + metamifop at 80 or 90 g/ha at 15 DAS (days after sowing) can be recommended for the effective management of weed seed bank in wet direct-seeded rice. Top Keywords Bispyribac-sodium + metamifop, Broad-leaved weeds, Direct-seeded rice, Grasses Penoxsulam + cyhalofop-butyl, Sedges, Weed seed bank. Top |