Effects of Soil Cadmium Contamination on Grain Yield and Cadmium Accumulation in Different Plant Parts of Three Rice Genotypes

The zinc (Zn) - rich tailing from Zn mines often causes cadmium (Cd) poisoning in people living downstream. This study evaluated the effect of soil Cd contamination on grain yield and accumulation of Cd and Zn in different plant parts among three rice genotypes. The experiment was conducted to study the interaction effect of the three rice varieties namely KH CMU, KDML 105 and Sang Yod and the soil mixtures with different level of Zn tailings mine from Mae Sot District, Tak Province, Thailand, which designated M-0, M-1, M-20 and M-40. Increasing doses of the tailings increased the brown rice Cd and Zn in all three genotypes, while increasing the grain yield in Sang Yod, depressing it in KDML105 and having only a mild effect in KH CMU. The genotype KDML105 had the highest concentration of Cd and Zn in its brown rice. Higher application rate of the mine tailings increased both grain and straw yield in Sang Yod, while increased straw yield but decreased grain yield in KDML105, and decreased grain yield at the highest rate of tailings in KH CMU. Different response of rice genotypes to soil Cd with respect to yield and Cd accumulation in rice grain should be exploited by rice breeders to tailor more efficient rice genotypes for the areas of soil Cd contamination. (C) 2019 Friends Science Publishers