Genetic analysis and screening of Indian landraces of rice for submergence tolerance in target production environment (TPE)

Abstract

Complete submergence is one of the most important abiotic stress constraining rice production in India. From the past few decades effect of this stress has intensified and is anticipated to increase in coming years as a result of global climate change. Rice has developed many adaptive mechanisms to grow well in flood ecosystems however, too much water for long time at any stage of plant growth can lead to serious injuries like decaying of plant parts, lodging and reperfusion causing total crop loss. Because of these conditions, farmers usually rely on traditional landraces that can survive through this stress, despite the fact that these tends to be very low yielding. In the present study, 660 rice landraces along with checks were subjected to screening for submergence tolerance at vegetative stage in target production environment. Identification of tolerant genotypes was based on the survival percentage of plants and recovery by which they grown new tillers and leaves. Principle component analysis revealed three principle components accounted for 99.9 per cent of total variation. Regeneration percentage of tillers found to be the most discriminating character and possess additive gene action. Confirmation through cluster analysis grouped the tolerant and susceptible genotypes in the respective clusters. Results of screening showed that, out of 660 accessions, three accessions viz., IC388692, IC377169 and IC205953 have highest tolerance to 14 days of submergence and the survival ability was similar to the tolerant checks FR13A and CO 43-Sub1. Apart from the above three accessions, eight accessions viz., IC216378, IC126210, IC114413, IC386238, IC133584, IC114971, RL-1312 and RL-3055 scored 1 for faster regeneration of tillers denoting the ability to have good tolerance for submergence stress.