Effect of Cadmium Stress on Morphophysiological Traits of Rice Seedlings

Cadmium is an important pollutant of heavy metals, which is very toxic to plants and animals. Rice is the most popular food among Iranians and the presence of heavy metals in trace level in rice has received special attention because they are directly related to health. In order to evaluate the tolerance of rice genotypes to cadmium, 40 rice genotypes under hydroponic conditions were used for seedling tolerance and absorption of cadmium in different levels of stress (control, 100, 200 and 300 μm cadmium) and in a split plot experiment in a completely randomized design template was examined. The results showed a significant difference between genotypes. In terms of cadmium adsorption, genotypes of Mirtarom, Sangtarom, F12L49-3، 229R and KOSHIHIKARI had the lowest cadmium adsorption. Principal components analysis based on the traits evaluated for cadmium show 70.160, 70.357, 72.641 and 66.305 percent of the changes by the first and second components, respectively, at the control levels of 100, 200 and 300 micromolar of cadmium. Cluster analysis based on the studied traits at control, 100, 200 and 300 micromolar of cadmium classified the genotypes in two, five, three and two clusters, respectively. In sum, genotypes of Sangtarom, Mirtarom, F12L49-3, 229R and KOSHIHIKARI as genotypes tolerant to cadmium and genotypes of M30, ARIAS HALUS and Kinan Dang Patong as genotypes classified as Noncompliant were determined according to biplot analysis and cluster analysis. The generations obtained from crossing between tolerant and susceptible cultivars could be used as segregating population in genetic and molecular studies.