Molecular Mapping of QTLs for Drought Related Traits at Seedling Stage under PEG Induced Stress Conditions in Rice

Differential response of seedling characteristics under water stress conditions is known to be associated with drought resistance in rice and elucidation of its genetics could be of help in breeding for tolerance to the stress. A recombinant inbred population derived from the cross between a semi-dwarf variety IR64 and landrace INRC10192 was grown in hydroponic culture and phenotyped for varied responses of seedlings to water deficit imposed by poly ethylene glycol (PEG). The ratio between mean value of seedling trait under stress and control conditions was used for assessing drought tolerance. In all 19 putative QTL relating to five seedling traits viz., shoot length, maximum root length, shoot dry weight, root dry weight and root to shoot dry weight ratio under PEG induced stress conditions were identified confirms that the traditional tall landraces as the one chosen for the study posses hitherto unexploited drought tolerant genes and utilization of them as potential donors in breeding for yield enhancement would be rewarding. They might be useful for improving drought resistance of rice by marker assisted selection/breeding.