Performance and Water-use Efficiency of Rice Relative to Establishment Methods in Northwestern Indo-Gangetic Plains

Abstract

Gains or losses in grain yield and water-use efficiency of aerobic direct-seeded rice (Oryza sativa L.) must be considered before promoting this technology in areas where this is not common. In the northwestern Indo-Gangetic Plains (IGP) of South Asia, irrigation water for rice production is becoming scarce because of depleting surface and groundwater resources. The objective of this study was to compare the crop performance and water-use efficiency of 10 selected rice cultivars between aerobic direct-seeded rice (ADSR) and conventional puddled transplanted rice (CPTR) on a sandy loam soil in Punjab Agricultural University (PAU), Ludhiana, India. Grain yields were similar between ADSR and CPTR for cultivars PR-120, Punjab Mehak 1, Fang-ai-zan, and RH-664. Grain yields of the other cultivars decreased significantly in ADSR compared with CPTR. PAU-201, a medium-duration cultivar, had the highest grain yields in each crop establishment method, followed by PR-120. Water-use efficiency (WUE) values for Fang-ai-zan, RH-257 (hybrid), PAU-201, and PR-120 were significantly higher than the WUE of any other cultivar, and they also had high values for stress-tolerance index (STI). Averaged across cultivars, WUE was similar in ADSR and CPTR as yield reduction in ADSR overweighed the benefit of water saving. We recommend that for more economic water use in the northwestern part of IGP, growing cultivars such as Fang-ai-zan, RH-257, PR-120, and PAU-201 in ADSR because of their lower water requirement, yield maintenance, and relatively higher STI. Correlation coefficients between STIs revealed that STI, mean productivity (MP), and geometric mean productivity (GMP) were the best criteria for the selection of high-yielding cultivars under ADSR and CPTR.