Effect of SRI (System of Rice Intensification) practices on the yield attributes, yield and water productivity of rice (Oryza sativa L.)

Abstract

Field experiments were conducted during the wet and dry seasons of 2002 and 2003 at Tamil Nadu Agricultural University Farm, Coimbatore, India to study the effect of practices recommended in the system of rice intensification (SRI) on the yield attributes, yield and water productivity of rice (Oryza sativa L.). The experiments were laid out in a randomized block design with three replications. The treatments were i) using 21-day-old (conventional) or 14-day-old (dapog nursery) seedlings; ii) crop geometry at 15 × 10 cm, 20 × 20 cm or 25 × 25 cm; iii) irrigation at 5.0 cm depth (conventional) or 2.0 cm depth when hair-line cracks developed (SRI); iv) weed control (conventional and SRI weeding), and v) nitrogen management (recommended and LCC-based N application) during the wet season of 2002. During the second crop season (dry season, 2003), all the treatments were repeated except nitrogen management, since there was no response to LCC-based N in the wet season. The treatments were slightly modified based on the results of the wet season crop. The yield attributes (panicle length, number of panicles hill-1, total number of grains panicle-1) were significantly higher in the treatment involving 14-day-old seedlings + 25 × 25 cm spacing + water-saving irrigation + LCC-based N management + SRI weeding than in the other treatments during the wet season. During the dry season, greater values of panicle length, no. of panicles hill-1 and filled grains panicle-1 were recorded in the treatment combination involving 14-day-old seedlings + 25 × 25 cm spacing + water-saving irrigation + SRI weeding. The grain yield and water productivity were significantly increased when applying SRI weeding with 14-day-old dapog seedlings planted at 25 × 25 cm spacing to achieve yields of 7009 and 5655 kg ha-1, and 0.610 kg and 0.494 kg per m3 of water, respectively, in the wet and dry seasons.