外源茉莉酸对水稻幼苗根系砷积累及抗逆应答效应

Effects of Exogenous Jasmonic Acid on Arsenic Accumulation and Response to Stress in Roots of Rice Seedlings

砷(As)污染对作物生长有毒害作用,导致作物品质和产量降低,因此亟需采取安全有效的策略以减轻其毒害.采用水培法,通过荧光探针定位技术、差速离心技术和傅里叶红外光谱技术(FTIR)研究外源茉莉酸(JA)对水稻幼苗As积累及抗逆应答的影响.结果表明,外源添加JA使水稻地下部和地上部的As含量分别降低31.4%和51.4%,显著降低细胞壁和细胞液中的As含量.JA改变亚细胞组分中As的分布比例,使细胞壁中As的分布比例提高16.4%,细胞液中As的分布比例降低17.3%,增强细胞壁对As的固定,减少细胞液中的As含量.此外,JA提高根细胞中SOD、CAT、GSH和PEPC的水平,降低HO和MDA含量,减轻脂质过氧化损伤,调节碳氮代谢,缓解As毒害.研究为水稻As污染防治提供了新思路.

Arsenic(As)pollution has a toxic effect on crop growth,leading to reduced crop quality and yield.Therefore,it is urgent to explore safe and effective strategies to reduce its toxicity.In this experiment,hydroponics,fluorescent probe locating technology,differential centrifugation,and Fourier infrared spectroscopy(FTIR)analysis were used to research the effect of exogenous jasmonic acid(JA)on the accumulation and stress resistance of rice seedlings.The results showed that JA application reduced the As content in the roots and shoots of rice by 31.4%and 51.4%,respectively,and significantly reduced As content in the cell wall and soluble fractions of rice roots.JA changed the distribution ratio of As in the subcellular components.The distribution ratio of As in the cell wall increased by 16.4%,and the distribution ratio of soluble fractions decreased by 17.3%.JA enhanced the fixation of As by the cell wall and reduced the As content in the soluble fraction.Furthermore,JA increased the levels of SOD,CAT,GSH,and PEPC in root cells and reduced the contents of HOand MDA,indicating that JA reduced lipid peroxidation damage,regulated carbon and nitrogen metabolism,and alleviated As toxicity.This research provides a new approach for the prevention and control of rice As pollution.