College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China; Hubei Provincial Key Lab for Soil Environment and Pollution Remediation, Wuhan 430070, China; College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China.
Sci Total Environ. 2021 Feb 20;756:143848. doi: 10.1016/j.scitotenv.2020.143848. Epub 2020 Nov 20.
Beneficial effects of methyl jasmonate (MeJA) on plants under different abiotic conditions have long been demonstrated. This study aimed to figure out how exogenous MeJA mitigated high-Se toxicity in rice from plant physiology and gene express perspective to provide the theory and technique for safe production of Se-rich rice. The results showed that low concentrations of MeJA at 0.1-1.0 μM inhibited high-Se induced nonreversible toxicity by enhancing antioxidant-system and reducing HO and MDA content in rice seedlings. In comparison with control, addition of low concentrations of MeJA at 0.1-1.0 μM reduced the Se content in roots by 13.6-48.8% and in shoots by 52.6-59.9%. Besides, lower concentrations of MeJA decreased the Se(IV) transformation to SeCys and SeMet. The qRT-PCR analysis showed that application of low concentration of MeJA down-regulated the gene expression of OsNIP2;1, and OsPT2 in roots and OsNIP2;1, OsPT2, OsSBP1, and OsCS in shoots, which inhibited Se absorption. However, high concentrations of MeJA at 2.5-5.0 μM decreased antioxidant capacity and increased HO and MDA content in rice seedlings. The results suggested that MeJA at 0.1-1.0 μM can be used to mitigate high-Se toxicity in rice production. This research augments the knowledge for future utilization of MeJA in down-regulating Se levels in crops.
茉莉酸甲酯（MeJA）对不同非生物条件下植物的有益作用早已得到证实。本研究旨在从植物生理学和基因表达的角度探讨外源 MeJA 如何减轻水稻高硒毒性，为富硒水稻的安全生产提供理论和技术支持。结果表明，低浓度（0.1-1.0 μM）的 MeJA 抑制了高硒诱导的不可逆毒性，增强了抗氧化系统，降低了水稻幼苗中 HO 和 MDA 的含量。与对照相比，添加低浓度（0.1-1.0 μM）的 MeJA 可使根中硒含量降低 13.6-48.8%，茎叶中硒含量降低 52.6-59.9%。此外，低浓度的 MeJA 降低了 Se(IV)向 SeCys 和 SeMet 的转化。qRT-PCR 分析表明，低浓度 MeJA 的应用下调了根中 OsNIP2;1 和 OsPT2 以及茎叶中 OsNIP2;1、OsPT2、OsSBP1 和 OsCS 的基因表达，抑制了硒的吸收。然而，高浓度（2.5-5.0 μM）的 MeJA 降低了水稻幼苗的抗氧化能力，增加了 HO 和 MDA 的含量。结果表明，0.1-1.0 μM 的 MeJA 可用于减轻水稻生产中的高硒毒性。本研究为未来利用 MeJA 降低作物中硒含量提供了更多的知识。
