Evaluation of rice (Oryza sativa L.) yield parameters, productivity and economic viability under different planting techniques and weed control strategies

Abstract:

A field investigation carried out over the kharif seasons of 2022 and 2023 examined how alternative planting techniques and weed control strategies influenced the yield attributes, productivity and economic returns of rice (Oryza sativa). The study assessed sixteen treatment combinations derived from four planting techniques crossed with four weed control strategies, arranged in a split-plot layout with three replications. Planting techniques—namely transplanting at 20 × 10 cm, direct-seeded rice sown in rows 20 cm apart, drum-seeded rice at 20 × 10 cm and the system of rice intensification (SRI) at 20 × 20 cm—formed the main-plot treatments, whereas the weed control strategies occupied the sub-plots. These weed treatments included: Nominee Gold (bispyribac-sodium) at 25 g a.i. ha⁻¹ applied 25 days after sowing or transplanting; the same herbicide supplemented with a single hand weeding at 40 days; two hand weedings performed at 20 and 40 days; and an unweeded control. Across the planting techniques, SRI delivered the highest grain yield (32.09 and 34.46 q ha⁻¹), net income and benefit-cost ratio, whereas transplanting recorded the highest harvest index (46.74 and 47.63%). Among the weed control treatments, two hand weedings performed at 20 and 40 days—followed closely by the herbicide plus a single hand weeding at 40 days—proved most successful in lowering weed density and dry weight while boosting grain yield (34.29 and 36.73 q ha⁻¹), harvest index (48.30 and 48.82%) and net return. Both treatments emerged as the most productive and economically sound options for rice cultivation under the conditions of the study area.