Sowing methods and weed management for yield maximization in wet direct-seeded rice (Oryza sativa L.) cultivation in Tamil Nadu

Abstract

Wet direct-seeded rice has emerged as a viable alternative to traditional transplanted rice, overcoming labour and water scarcity challenges while mitigating rising cultivation costs. However, effective weed management practices are required to prevent severe yield losses due to heavy weed infestation. A field experiment was conducted during the Kharif seasons of 2020, 2021 and 2022 at the Department of Rice, Tamil Nadu Agricultural University in Coimbatore. The objective was to investigate various sowing methods and weed management practices to maximize yield in wet directseeded rice, utilizing a split-plot design with 3 replications. The results indicated that the paddy drum seeding method resulted in lower weed density, reduced weed dry weight, a higher number of productive tillers/m2 and a higher grain yield than other sowing methods. Among the weed management practices, the sequential use of preemergence (PE) Pretilachlor, followed by the early post-emergence (EPOE) herbicide bispyribac sodium for the first and second weed flushes at 25 and 45 days after sowing (DAS), effectively reduced both weed density and dry weight, while producing the highest number of productive tillers/m2 and resulted in a significantly higher grain yield of 5277 kg/ha compared to other sowing methods. Thus, the paddy drum seeded method, combined with the sequential application of PE herbicide pretilachlor at 0.75 kg/ha at 8 DAS fb EPoE herbicide Bispyribac sodium at 25 g/ha for the 1st and 2nd weed flushes at 25 and 45 DAS, effectively enhances productivity and weed control in wet direct-seeded rice.