[01] Yuankang Liu, School of Environmental & Safety Engineering, Changzhou University, Changzhou, China. [02] Kaiqiang Chu, School of Environmental & Safety Engineering, Changzhou University, Changzhou, China. [03] Yuhong Chai, School of Environmental & Safety Engineering, Changzhou University, Changzhou, China. [04] Jianguo Liu, School of Environmental & Safety Engineering, Changzhou University, Changzhou, China.

Effects of different types of silicon (Si) applications (Nano-Si and common Si) on Cd translocation, accumulation and distribution in rice plants were investigated with different rice cultivars of different Cd uptake abilities under different soil Cd levels. The results present that Si applications reduced the translocation factors (TFs) of Cd from roots to shoots and from shoots to the grains largely and generally significantly (P < 0.05). Under soil Cd treatments (5 and 10 mg/kg), the TFs from roots to shoots were reduced by 16.98% - 26.92% and 30.19% - 46.15% by common Si and Nano-Si treatment respectively, and the TFs from shoots to the grains were reduced by 7.53% - 17.86% and 39.64% - 33.33% respectively. Si applications also decreased Cd accumulations and distribution proportions in rice shoots and grains largely and generally significantly (P < 0.05). Under soil Cd treatments, Cd accumulations in rice shoots were decreased by 17.57% - 29.80% and 28.74% - 50.50% by common Si and Si Nano-Si respectively. Cd accumulations in rice grains were decreased by 22.54% - 42.09% and 35.61% - 66.38% by common Si and Nano-Si respectively. The effects were in the order: Nano-Si > common Si, high Cd accumulation cultivar (Yangdao 6) > low Cd accumulation cultivar (Yu 44), and heavy soil Cd pollution (10 mg/kg) > moderate soil Cd pollution (5 mg/kg). The results indicate that Nano-Si is better than common Si in cutting down Cd translocation from rice roots to shoots and from shoots to the grains, and in lowering Cd accumulation and distribution in rice grains.

Cadmium (Cd), Rice (Oryza sativa L.), Silicon (Si), Translocation, Accumulation

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