Vol. 11, Special Issue 3 (2022)

Author(s):
Amrit Tamuly, Rahul Kumar Verma, Munmi Phukon, Pompi Dutta, Sruthi R, Pradip Chandra Dey, Milon Jyoti Konwar and Sanjay Kumar Chetia

Abstract:
Rice is one of the important staple cereals which are consumed as a main part of diet by more than half of world’s population. Rice production in India accounts to more than 40% of country’s grain production. Rice is a major crop of Assam and it plays a major role in state’s economy. A panel of 50 upland diverse rice cultivars collected from different parts of India were genotyped using SSR markers distributed across the 12 chromosomes in rice. The phenotyping using various yield traits were performed in rainout shelter as well as in open field conditions. A significant variation among the genotypes for all the characters under drought stress as well as in irrigated conditions study was obtained indicating the existence of considerable amount of variability among the genotypes selected for study. Grain yield is the most important character for selection under drought stress condition. Mannitol treatment may be an effective tool for selecting genotypes in drought stress. The log likelihood revealed by Structure showed the optimum subpopulations (K) value as 2 (K= 2), which indicated that the entire population can be grouped into two subgroups. The results clearly indicated that two subgroups were formed due to the different adaptation behaviour of cultivars to drought stress and yield attributes under drought. A total of forty-three cultivars were grouped in cluster I however, remaining seven cultivars were grouped in cluster II. The assessment of genetic diversity among the cultivars is pre requisite for any successful breeding programme.