Studies on Cadmium Tolerance Differences of Seed Germination and Growth of Roots and Shoots in Different Rice Varieties

To ascertain the genotypic difference of cadmium tolerance,twenty-six rice varieties widely cultivated in central Hunan were used to analyze the effect of cadmium stress( 0. 5 mmol / L) on seed germination and the growth of roots and shoots after seed germination of different rice varieties. The results showed that the cadmium stress had not a significant impact on the germination rate and germination index of rice seed,but it had a significant effect on seed vigor index and the growth of roots and shoots. The inhibition of cadmium stress was larger on the growth of roots than on that of shoots. Large differences of cadmium stress tolerance existed among different varieties. The cluster analysis on comprehensive inhibition effect divided the tested varieties into three types: sensitive,intermediate,tolerant. Among them,Y Liangyou 1 and Q You 1127 belonged to the tolerant type with a relatively strong cadmium tolerance.