Evaluation of Recombinant Inbreed Lines (RIL) population of upland rice under stress and non stress conditions for grain yield and drought tolerance

Drought is the major abiotic factor that limit rice productivity in rainfed and upland occuring ecosystems; worldwide, it reduces yield by 15–50 % depending on the stress impact on crop growth period. Stress period more than 7-14 days reduction is observed in all the parameters i.e. average plant height 12.9-29.5%, panicle number 41.6-65.4%, yield of inbred lines 17.34 -86.04% followed by an average of overall 44.86% over non stress condition. Similarly it was found that biomass, harvest index, filled grain per panicle, total grain per panicle, fertility % and so on were reduced under stress condition in comparison to congenial condition.Variation in drought susceptibility index (DSI) and drought resistant index (DRI) in the inbred lines ranges 1.081 to 2.116 and 0.04 to 2.80 respectively. Significant variations observed in the population for different agronomical traits and derived indices would facilitate selection of recombinant inbred lines (RILs) with drought tolerance and high yielding.