Abstract
The mechanism of salt tolerance in rice was investigated by comparing two indica varieties differing in salt sensitivity; Nona Bokra as a salt tolerant variety and Chiem Chanh as a salt sensitive one. The growth of Nona Bokra after salinization was much greater than that of Chiem Chanh. The photosynthetic rates of both varieties declined with increased leaf Na+ content. The leaf Na+ content of Nona Bokra did not increase very much after salinization with 150mM NaCl, and remained relatively low at high saline levels. The results obtained suggest that Nona Bokra, which is salt tolerant, could maintain in low Na+ content in the most active leaves for a long time at relatively high NaCl concentration in culture solution and consequently could maintain high photosynthetic rate.
