Screening of rice landraces for potential drought tolerance through comparative studies of genetic variability and principal component analysis

To identify stable yielding rice landraces with optimum drought tolerance ability, the present comparative study of genetic variability and principal component analysis was carried out based on different morphological traits of 60 landraces of northeast India belonging to upland rice. The sensitivity of the landraces under drought stress conditions was confrmed by the frst-order statistics of genetic variation as well as Principal component analysis (PCA) since comparatively more numbers (6) of principal components were found under drought stress over the irrigated conditions with 74.12 per cent of cumulative variability. Characters viz., leaf rolling index, root: culm ratio, the number of spikelets per panicle, the number of flled grains per panicle, 100 seed weight and grain yield per plant were identified as suitable selection indexes for landraces under drought stress conditions. Based upon the eigenvalue and scattered diagram analysis under PCA, the landraces viz., Garomalati, Chikanswari Kabar, Turkey, Tarkol, Maimi Taukha and Madoop were found to be diverse and promising genotypes under drought stress. Hence, these landraces may be utilised as potential parents in the future breeding programme.