Performance of semi-dry rice (Oryza sativa) varieties under different plant spacing

Semi-dry rice (Oryza sativa L.) is a new attractive alternative to the conventional puddled transplanted rice production technology for lowering labour and irrigation water requirements in the command areas of India. A study was carried out during the rainy (kharif) seasons of 2019 and 2020 at College of Agriculture (University of. Agricultural Sciences, Bengaluru, Karnataka), V C Farm, Mandya, Karnataka, to assess the growth and yield of semi dry rice varieties under different plant spacing. The experiment was conducted in a split-plot design (SPD) comprised of various combinations of two plant spacing (20 cm and 30 cm row spacing) allocated to the main plots and eight varieties (V1, KMP-175; V2, RNR-15048; V3, RNR-15038; V4, Rasi; V5, MTU-1001; V6, MTU-1010; V7, IR-64 and V8, Gangavathisona) in sub plots, replicated thrice. The result revealed that 20 cm row spacing recorded higher plant height (82.7 cm), dry matter production (90.00 g/hill), leaf area index (4.57), panicle/m (292), grain yield (4605 kg/ha) and straw yield (6389 kg/ha) compared to 30 cm spacing. Among the different varieties KMP-175 produced higher plant height (90.3 cm), dry matter production (121.16 g/hill), leaf area index (5.04), panicle length (22.47 cm), grain yield (5086 kg/ha) and straw yield (7139 kg/ha) compared to other varieties. The overall analysis revealed that KMP-175 under closer crop spacing (20 cm row spacing) was the best management practices for enhancing yield of semi dry rice.