Comparison of the system of rice intensification (SRI), recommended practices, and farmers’ methods of rice ( Oryza sativa L.) production in the humid tropics of Kerala, India

摘要

Field experiments were conducted to compare the System of Rice Intensification (SRI) with the best management recommendations and farmers’ practices of rice ( Oryza sativa L.) production. The experimental variables included combinations of seedling number and age (10 day-old single vs. 20 day-old two seedlings per hill), spacing (25 x 25 cm vs. 20 x 15 cm), irrigation (intermittent irrigation vs. continuous flooding), and weed control (cono-weeding vs. manual weeding) treatments, besides farmers’ practice (control). The trial was laid out in completely randomized factorial design, replicated thrice. Highest grain yield (4467 kg ha–1) and net returns (Rs 17745 ha–1) were obtained for the suite of best management practices (planting two 20 days-old seedlings hill–1 at 20 x15 cm + intermittent irrigation and cono-weeding). Yield under SRI management (planting 10 day-old single seedlings at 25 x 25 cm + intermittent irrigation and cono-weeding: 3326 kg ha–1) was lower than that of recommended practices (20 day-old two seedlings at 20 x15cm+continuous irrigation and hand weeding: 4310 kg ha–1) but was greater than that of farmers’ practices (2643 kg ha–1). Planting 10 day-old single seedlings at 25 x 25 cm spacing had little impact on yield under the experimental conditions. Although intermittent irrigation and continuous flooding were statistically at par, cono-weeding reduced the labour required for weeding by 35 man-days ha–1 and labour cost by Rs 3125 ha–1. Farmers’ participatory evaluation revealed that planting of one or two young seedlings hill–1 at specified spacing and employing conoweeding and intermittent irrigation are economically viable technologies.