Efficacy of pre-and post-emergence ready-mix herbicides in rainfed lowland wet-seeded rice

Abstract

The experiment was conducted during Kharif (rainy) season of 2019 to assess comparative efficacy of low dose high efficiency herbicides in providing season-long weed control in direct wet-seeded rainfed lowland rice at Integrated Farming System Research Station (IFSRS), Karamana, Kerala. The rice yield reduction due to unmanaged weeds in unweeded control in rainfed lowland rice was estimated to be 59.75%. Rice grain yield obtained was 159.9% higher in bensulfuron-methyl + pretilachlor fb HW at 40 DAS (5.46 t/ha) compared to weedy check with a B: C ratio of 1.83 and was at par with penoxsulam + cyhalofop-butyl fb HW at 40 DAS (5.35 t/ha) with a B:C ratio of 1.77. Application of ready mix of either bensulfuron-methyl + pretilachlor 60 + 600 g/ha at 3 DAS or penoxsulam + cyhalofop-butyl 150 g/ha at 20 DAS both fb HW at 40 DAS was observed as the most effective weed management strategy in wet-seeded lowland rainfed rice.