Molecular characterization of rice genotypes having Variability in heat tolerance

Abstract

The study entitled “Molecular characterization of rice genotypes having variability in heat tolerance” was conducted at the Department of Plant Physiology, College of Agriculture, Vellayani, Thiruvananthapuram. Rice (O. sativa) is very sensitive to high temperature especially at the reproductive and grain filling stage which leads to higher spikelet sterility and ultimately yield losses. The present investigation was, therefore, carried out with the objective to study the variation in rice genotypes for heat tolerance using microsatellite markers. In the present study, a set of 50 SSR primers were employed to assess the genetic diversity among the 10 genotypes. Out of 50 markers, 11 markers showed polymorphism, the marker RM6100 was found as a functional marker associated with heat tolerance in rice, and is functional for further crop breeding programmes. A dendrogram was generated with the aim of analyzing the relationships between the 10 genotypes tested. The genetic similarity index ranged from 0.1 to 0.833. The lowest value 0.1was obtained between PTB7 and CR Dhan202 while highest similarity value (0.833) calculated was between the PTB7 and CR Dhan204 genotypes. However, the genetic diversity analysis with SSR markers will contribute to maximize the selection of diverse parents in the future rice breeding program or development of heat tolerant cultivars.