Characteristics and Influencing Factors of Cadmium Accumulation in Different Rice Varieties Under Cadmium Contaminated Field Conditions

Abstract

Eight rice varieties suitable for local cultivation were selected and field tests were carried out to compare the accumulation, absorption, and transport characteristics of Cd. The rice varieties with low Cd accumulation were screened, and the factors affecting the accumulation degree and stability of rice were analyzed. The results showed that:①According to the comprehensive accumulation index(PN) evaluation method, the rice varieties with low PN ability for Cd were selected as follows:Chuanyou 3203, Chuanyou 6203, Dejing 6, and Shenyou 17. ②Considering the Cd content and yield of rice, Chuanyou 3203 and Chuanyou 6203 are suitable for planting in this region, which guarantees a safe Cd content in and high yield of rice. ③The contents of Cd in Chuanyou 3203 and Chuanyou 6203 were significantly lower than those of other rice varieties and stable under different pH and total Cd ranges and soil conditions. ④The difference between rice varieties had a significant effect on rice enrichment ability, but little effect on translocation from stem to leaf. The low enrichment coefficient of Chuanyou 3203 and Chuanyou 6203, combined with low translocation, demonstrated the low Cd enrichment capacity of rice. ⑤Correlation analysis showed that the Cd content was most affected by the enrichment coefficient of rice, and least affected by the total Cd content of rhizosphere soil.