Impact of Early Post-emergence Herbicides and Weeding Schedules on Weed Dynamics and Yield of Transplanted Rice

Abstract

Weeds pose a significant threat to rice productivity by competing for essential resources, especially during the early stages of crop establishment. A field experiment was conducted by ADT - 43 rice variety to evaluate the efficacy of selected early post-emergence (EPOE) herbicides, in combination with hand weeding, on weed control, dry matter production, weed control efficiency (WCE), yield and economic returns in transplanted rice during Navarai season 2024. The experiment was laid out in a Randomized Block Design (RBD) comprising eight treatments with three replications. Among the eight treatments, application of Triafamone @ 45 g a.i. ha⁻¹ on 10 DAT followed by hand weeding at 40 DAT (T4) recorded the lowest total weed population and dry matter production, with the highest WCE at both 30 and 60 DAT. This treatment also led to maximum grain yield, straw yield, net income, and benefit-cost ratio (BCR) (2.16), indicating superior weed suppression and economic viability. Pyrazosulfuron ethyl @ 21 g a.i. ha⁻¹ + hand weeding at 40 DAT (T8) was the next best alternative. Conversely, the unweeded control exhibited maximum weed growth and the lowest yield and economic returns. These results highlight the critical importance of integrating EPOE herbicide application with timely manual intervention to ensure effective weed control and economic sustainability in rice cultivation.