Variations Among Rice Genotypes and Cultivars on Root Oxidation and Pb Uptake

In order to understand the mechanisms of the variation among rice genotypes and cultivars in Pb uptake and accumulations, pot soil experiments were conducted with six rice cultivars that varied greatly in Pb uptake. The results showed that root oxidation abilities of the rice plants differed with genotypes and cultivars, and those of the cultivars with indica consanguinity were significantly higher than those of the cultivars with japonica consanguinity. The differences among the rice genotypes and cultivars in plant Pb uptake and accumulation abilities followed the similar trends to the differences in root oxidation abilities. Root oxidation abilities of the rice cultivars correlated positively and significantly (P < 0.01 or 0.05) with their Pb concentrations and Pb quantity accumulations in rice plants. The results indicate that the oxidation ability of rice root is one of the main mechanisms that dominate Pb uptake and accumulation of the rice plant.