Abstract
Diversity in uncharacterized rice germplasm grown under normal and water stress conditions was measured by various traits i.e. seed and root shoot traits (seed length, seed width, seed thickness, seed length width ratio, 1000 grain weight, shoot length, root length, shoot fresh weight, root fresh weight, root shoot ratio, root numbers and root thickness). Genotypic differences among the rice accession were determined by variances and association analysis of the desirable traits to set the selection criteria of the genotypes under water stress condition. The trait association along with the entire set of germplasm provided the information of the diversity that responsible for the high yield production of the crop in water stress environment. Some important traits showed positive significant correlation i.e., fresh root weight, shoot thickness and root numbers showed positive significant association (r=0.2530**, r=0.2891**, r=0.4626**, r=0.4515**, r=0.5781**, r=0.7164**, r=0.0603**, r= 0.5570**, r=0.5824**) with shoot length, root length, fresh root shoot weight. The seed thickness has positive correlation (r= 0.104**, r=0.246**) with seed length and seed width. The genotypes with longer roots (KSK-282, KSK-234, PS2) performed well under water stress condition were recommended for further development of drought tolerant germplasm. Twelve polymorphic SSR markers were used to assess molecular diversity of the selected germplasm. The average PIC values (0.464), polymorphism% (93.75), polymorphic alleles (3.58) and total number of alleles (3.83) were determined among the genotypes. The PIC value and number of alleles observed indicated moderate molecular diversity in the selected germplasm. The genotypes with better agro-morphological traits and long roots could be very useful for the development of new breeding populations for adverse environments.