紫云英还田配施石灰对水稻镉吸收转运的影响

采用田间小区试验,研究了紫云英(CMV)与石灰(L)单施及两者配施(CMVL)对土壤Cd有效性、水稻根表胶膜及Cd吸收转运的影响.结果表明:L与CMVL处理土壤pH值分别显著提高2.11～2.43和1.68～2.48个单位、二乙烯三胺五乙酸提取态(DTPA-Cd)含量分别显著降低18.88％～40.53％和20.74％...

Effect of Chinese milk vetch combined with lime on cadmium uptake and translocation in rice

A plot experiment was conducted to study the combined effects of Chinese milk vetch (CMV) and lime (L) on the availability of Cd in soil, the concentrations of Cd in Fe-Mn plaque on roots and the uptake and transport of Cd in rice plants. The results showed that soil pH value was significantly increased by 2.11~2.43 and 1.68~2.48 units, and DTPA-Cd concentration decreased by 18.88%~40.53% and 20.74%~36.85% in L and CMVL treatments, respectively, while it had no significant effect on them in CMV treatment. The Cd concentration in Fe-Mn plaque on rice roots at maturity in CMV treatment was significantly increased by 86.72%, that in roots was increased by 124.27% while that of Cd in grains was increased by 58.54%, which the transport coefficient of Cd from leaf to grain was increased by 5.58 times. The Cd concentration in Fe-Mn plaque on rice roots at maturity in L and CMVL treatments were significantly increased by 34.86% and 42.42%, while the transport coefficient of Cd from Fe-Mn plaque on rice root to root significantly increased by 170.6% and 158.8%, respectively. However, the transport coefficient of Cd from root to stem in L and CMVL treatments was significantly decreased by 75.87% and 74.71%, while those of Cd from root to grains decreased by 74.38% and 68.13%, respectively. Cd concentrations of rice grains in L and CMVL treatments were significantly reduced by 54.88% and 51.83%, respectively. Pearson correlations indicated that soil pH, DTPA-Cd and Cd concentration in Fe-Mn plaque on roots were the key factors on the Cd concentration of rice grains. Chinese milk vetch combined lime to Cd-contaminated rice fields can significantly reduce the Cd in rice grains.