Genetic analysis of cold tolerance in rice

Abstract

One hundred thirty-four rice varieties were examined for cold tolerance. Seedling tolerance was scored by growing seedlings in the phytotron in Yoshida's culture medium at 10 °C for 30 days and applying IRRI's Standard Evaluation System of Rice. Similarly, adventitious root regeneration was scored by growing seedlings in Yoshida's culture medium at 10 °C for 10 days. Rice varieties could be grouped into four categories according to reactions for cold tolerance at two stages of growth. Inheritance of cold tolerance was examined in seven hybrids between tolerant and nontolerant parents. Cold tolerance as measured by leaf yellowing is governed by a single dominant gene. A single dominant gene also controls cold tolerance as measured by root regeneration ability.