[01] Kaiqiang Chu, School of Environmental & Safety Engineering, Changzhou University, Changzhou, China. [02] Xuanhua Zhang, School of Environmental & Safety Engineering, Changzhou University, Changzhou, China. [03] Rongyan Shen, School of Environmental & Safety Engineering, Changzhou University, Changzhou, China. [04] Jianguo Liu, School of Environmental & Safety Engineering, Changzhou University, Changzhou, China.

By designing different silicon (Si) application levels (low, medium and high) and different Si application methods (one time and two times), the effects of Si application on grain yields and lead (Pb) concentrations of rice were conducted with two rice cultivars differed in grain Pb accumulations. The results showed that the grain yields of Yangdao 6 (high grain Pb accumulator) were raised by 2.22% - 7.79%, and that of Yu 44 (low grain Pb accumulator) were raised by 0.47% - 6.22% by the Si applications, compared to the control. The grain Pb concentrations of Yangdao 6 were reduced by 43.69% - 84.16%, and that of Yu 44 were cut by 36.07% - 79.37% by the Si applications. The grain yields increased, but grain Pb concentrations decreased sharply, with the rises of Si application levels and Si application times. The effects of Si applications on grain yields and Pb concentrations of rice were higher in Yangdao 6 than in Yu 44. The effects of Si applications on grain Pb concentrations were much higher than on grain yields. Grain yield can be raised by 6% or more, and grain Pb concentration can be reduced by 80% or more, by high level and two times Si application in rice plantation.

Rice (Oryza sativa L.), Silicon (Si), Lead (Pb), Cultivar, Grain

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