Cadmium-stress mitigation through gene expression of rice and silicon addition

• Published in: Plant growth regulation 2017-01, Vol.81 (1), p.91-101
• Main Authors: Lin, Hongmei, Fang, Changxun, Li, Yingzhe, Lin, Weiwei, He, Jianyu, Lin, Ruiyu, Lin, Wenxiong
• Format: Article
• Language: English
• Subjects: Agriculture; Biomedical and Life Sciences; Cadmium; Crop production; Enzymatic activity; Life Sciences; Original Paper; Oxidizing agents; Plant Anatomy/Development; Plant Physiology; Plant Sciences; Silicon; Sustainable agriculture; Sustainable development
• ISSN: 0167-6903; 1573-5087
• DOI: 10.1007/s10725-016-0191-x

Cadmium (Cd) pollution is one of the major concerns in the development of sustainable agriculture, particularly for rice production. Silicon (Si) was recently recognized for its ability to mitigate a variety of abiotic stresses including that caused by Cd on rice. However, mechanism of the complex process is still not fully understood. Under Cd-stress, the low Si-influx 1-RNAi transgenic Lemont rice ( Lsi1 -RNAi line) exhibited an increased Cd-uptake over its counterparts, the wild type and the Lsi1 -overexpression transgenic rice ( Lsi1 -OE line). In contrast, the Lsi1 expression-enhanced Lsi1 -OE line showed the greatest Si-uptake among the three lines, with the highest activities on anti-oxidants (such as, superoxide dismutase) and the lowest content of malondialdehyde. Lsi1 also displayed a negative regulation on Low Cd gene and the natural resistance-associated macrophage proteins, Nramp5 , indicating its capacity to alleviate Cd-stress on rice. The results obtained by this study suggested that the mitigation of Cd-toxicity on rice by Si might involve functions, such as the inhibition on Cd-uptake and transport and the enhancement on anti-oxidative enzyme activities, as well as the Lsi1 -related expression on regulation of Si-uptake in rice. A new avenue might become available for overcoming the rampant pollution that threatens the rice production in China.