Effects of Cadmium Tolerance on Seed Germination of eight diffrent rice (Oriza sativa L.) varieties

Abstract:

To explore the ability of cadmium resistance between the different rice genotypes and to find the effects on the rice germination when exposed to the different concentration of cadmium. Method: Eight kinds of rice were planted by using hydroponic and we conducted a comprehensive evaluation on the ability of resistance to cadmium stress between the different rice genotypes through the clustering analysis. Results: On account of the various genotypes and different physiological mechanism, there were a large difference on their cadmium resistance. The effect of mild cadmium stress on the seed germination of rice was more significant at the single inhibitory effect on rice seed vigor.With the increase of stress concentration, the effect of rice seed germination was greater.Sensitive varieties seems to be more brittle of rice root tip and bud color can not be timely turn to green phenomenon when under midle Cd stress. The comprehensive character of the index under mild heavy metal stress was more consistent with the correlation curve. Therefore, the selection of heavy metal resistant varieties under the condition of mild heavy metal stress was the most suitable to the actual situation.These eigth varieties of rice for experiment were divided into three types through the cluster analysis, which were tolerant respectively,sensitive and intermediate.The hybrid rice including G46-B,Ⅱ-32B,and R3203 were proved to be tolerant, which had the strongest ability of cadmium resistance.While the Wushansimiao, Guichao-2 and Guiyu-7 were the sensitive type and the cadmium resistance were the weakest.The results of this study provide valuable clues and materials for the breeding of heavy metal resistant varieties.