Methyl jasmonate improved yield of both rice varieties under arsenic toxicity by alleviating oxidative stress through increasing the activity of antioxidant enzymes and decreasing arsenic accumulation by modulating arsenic transporters. Human health and rice cultivation are threatened by arsenic (As) contamination. Methyl jasmonate (MJ), as a regulator of plant growth, plays an important role in response to environmental stresses. In the present study, the effects of MJ (0, 0.5 and 1 µM) on yield, biochemical and molecular traits of two rice varieties (T. hashemi and Fajr) under As treatments (0, 25 and 50 µM) were investigated. The results showed that As decreased chlorophyll content, chlorophyll fluorescence and biomass production; however, MJ improved photosynthetic pigments and plant growth. As also induced oxidative stress (H2O2 and MDA) in both rice varieties; however, MJ reduced the As-induced oxidative stress by regulating the activity of antioxidant enzymes and the ASA-GSH cycle. As treatment increased As accumulation in the roots and leaves, which is in line with the increased expression of Lsi1, Lsi2 and Lsi6 genes. However, MJ reduced As accumulation by decreasing the expression of Lsi1, Lsi2 and Lsi6. Fe translocation to leaves reduced under As treatments; while, MJ increased Fe accumulation in the leaves by increasing expression of FRDL1 and YSL2 transporters under As toxicity. As treatments, especially 50 μM, decreased yield and yield components of both rice varieties; however, MJ improved yield and yield components of both rice varieties. The findings of the present study indicate that MJ improved the growth and yield of both rice varieties under As toxicity by alleviating oxidative stress through increasing the activity of antioxidant enzymes and ASA-GSH cycle and decreasing As accumulation by modulating As transporters.

中文翻译：

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茉莉酸甲酯可减轻大米中的砷毒性。

茉莉酸甲酯通过增加抗氧化酶的活性来减轻氧化应激，通过调节砷转运蛋白来减少砷的积累，从而提高了砷毒害下两种水稻品种的产量。人类健康和水稻种植受到砷 (As) 污染的威胁。茉莉酸甲酯 (MJ) 作为植物生长的调节剂，在应对环境胁迫方面发挥着重要作用。在本研究中，研究了 MJ（0、0.5 和 1 µM）在 As 处理（0、25 和 50 µM）下对两个水稻品种（T. hashemi 和 Fajr）的产量、生化和分子性状的影响。结果表明，As降低了叶绿素含量、叶绿素荧光和生物量产量；然而，MJ 改善了光合色素和植物生长。还诱导了两种水稻品种的氧化应激（H2O2 和 MDA）；然而，MJ 通过调节抗氧化酶的活性和 ASA-GSH 循环来减少 As 诱导的氧化应激。As处理增加了根和叶中As的积累，这与Lsi1、Lsi2和Lsi6基因的表达增加是一致的。然而，MJ 通过降低 Lsi1、Lsi2 和 Lsi6 的表达来减少 As 的积累。在 As 处理下，Fe 向叶片的转移减少；同时，MJ 通过增加 FRDL1 和 YSL2 转运蛋白在 As 毒性下的表达来增加叶子中铁的积累。作为处理，尤其是 50 μM，两个水稻品种的产量和产量成分均下降；然而，MJ 提高了两个水稻品种的产量和产量成分。