Fifteen rice cultivars were grown in rainfed upland and exposed to severe water stress (soil moisture 5.5 – 9.0%) for ten days to evaluate them for drought tolerance. The study revealed that the cultivars IET 18645 and IET 18460 could maintain their assimilatory surface area 130.2 and 135.1 cm2plant−1, respectively even though their assimilatory units rolled to a maximum degree (leaf rolling score were 9 in both the cases) indicating their ability to escape drought through this mechanism. They were also able to maintain water potential in the leaf tissues to a desired extent. The cv. IET 18460 produced satisfactory grain yield of 2.18 t ha−1. However, cvs. IET 18645 and IET 18460 were at par with Bandana and all the three cvs. significantly registered higher grain yield compared to the check cv. Govind (1.13t ha−1). IET 18645, IET17509 and IET18781 exhibited strong dormancy behavior. IET 18645 showed longest grain dormancy of 28 days. Hence, IET 18645 can be identified as a potential donor for both drought tolerant upland rice cultivar and also longest grain dormancy.
upland rice, drought tolerance, seed dormancy, water potential
