Economic Evaluation of Indigenous Aromatic Rice Cultivars of Manipur under Different Weed Management Practices

Abstract

A field experiment was conducted at the Agronomy Research Farm (kharif 2021 and 2022), College of Agriculture, Central Agricultural University, Imphal (24°81′ N, 93°89′ E; 790 m above MSL), to evaluate the economic performance of aromatic rice cultivars under different weed management practices in the subtropical conditions of Manipur Valley. The experiment followed a split-plot design with three replications, featuring four cultivars- Khamanui Lungra (C1), Chaphemai (C2), Nambew (C3) and Chakhao Poireiton (C4) and five weed management strategies: W1-Manual weeding, W2-Pre emergence application of Pretilachlor 50% EC @ 450g a.i ha-1 followed by post emergence application of Metsulfuron methyl 10% + Chlorimuron ethyl 10% WP @ 4g a.i ha-1, W3-Pre emergence application of Pretilachlor 50% EC @ 450g a.i ha-1 followed by post emergence application of Penoxsulam 2.67% @ 25 g a.i ha-1, W4-Pre emergence application of Pyrazosulfuron Ethyl 10% WP @ 50 g a.i ha-1 followed by post-emergence Penoxsulan 2.67% @ 25g a.i ha-1 and W5-Control. Results revealed that among the cultivars, ‘Chaphemai’ (C2) recorded the highest plant height (196.9 cm), number of tillers per hill (11.3) and leaf area index (5.41), contributing to a superior grain yield of 4.69 t ha-1. The W3 treatment was most effective in suppressing weeds and enhancing growth, yield and profitability, recording the highest grain yield (3.28 t ha-1), net returns (₹1,04,062.87 ha-1) and benefit-cost ratio (3.32). In contrast, the control (W5) registered the lowest yield (20.26 q ha-1), net returns (₹39,785.53 ha-1) and B:C ratio (1.75), highlighting the economic risk of poor weed management in aromatic rice cultivar of Manipur. Economic analysis confirmed that the combination of Chaphemai with Pretilachlor+ Penoxulam (W3) treatment offered the most promising outcome for aromatic rice cultivation in the region, both agronomically and financially.