Division of Plant Biosciences, Kyungpook National University, Daegu, South Korea.
UoN Chair of Oman's Medicinal Plants & Marine Natural Products, University of Nizwa, Nizwa, Oman.
PLoS One. 2018 Mar 20;13(3):e0192650. doi: 10.1371/journal.pone.0192650. eCollection 2018.
This study investigated the regulatory role of exogenous salicylic acid (SA) in rice and its effects on toxic reactive oxygen and nitrogen species during short-term salinity stress. SA application (0.5 and 1.0 mM) during salinity-induced stress (100 mM NaCl) resulted in significantly longer shoot length and higher chlorophyll and biomass accumulation than with salinity stress alone. NaCl-induced reactive oxygen species production led to increased levels of lipid peroxidation in rice plants, which were significantly reduced following SA application. A similar finding was observed for superoxide dismutase; however, catalase (CAT) and ascorbate peroxidase (APX) were significantly reduced in rice plants treated with SA and NaCl alone and in combination. The relative mRNA expression of OsCATA and OsAPX1 was lower in rice plants during SA stress. Regarding nitrogenous species, S-nitrosothiol (SNO) was significantly reduced initially (one day after treatment [DAT]) but then increased in plants subjected to single or combined stress conditions. Genes related to SNO biosynthesis, S-nitrosoglutathione reductase (GSNOR1), NO synthase-like activity (NOA), and nitrite reductase (NIR) were also assessed. The mRNA expression of GSNOR1 was increased relative to that of the control, whereas OsNOA was expressed at higher levels in plants treated with SA and NaCl alone relative to the control. The mRNA expression of OsNR was decreased in plants subjected to single or combination treatment, except at 2 DAT, compared to the control. In conclusion, the current findings suggest that SA can regulate the generation of NaCl-induced oxygen and nitrogen reactive species in rice plants.
本研究探讨了外源水杨酸（SA）在水稻中的调节作用及其对短期盐胁迫下有毒活性氧和氮物种的影响。与单独盐胁迫相比，在盐胁迫（100 mM NaCl）期间施加 SA（0.5 和 1.0 mM）导致显著更长的茎长和更高的叶绿素和生物量积累。NaCl 诱导的活性氧产生导致水稻植物中脂质过氧化水平增加，而 SA 施加后显著降低。超氧化物歧化酶（SOD）也观察到类似的结果；然而，在单独用 SA 和 NaCl 处理以及组合处理的水稻植物中，过氧化氢酶（CAT）和抗坏血酸过氧化物酶（APX）显著降低。在 SA 胁迫期间，水稻中 OsCATA 和 OsAPX1 的相对 mRNA 表达水平较低。关于含氮物种，S-亚硝基硫醇（SNO）最初（处理后 1 天[DAT]）显著降低，但随后在单一或组合胁迫条件下的植物中增加。还评估了与 SNO 生物合成相关的基因、S-亚硝基谷胱甘肽还原酶（GSNOR1）、NO 合酶样活性（NOA）和亚硝酸盐还原酶（NIR）。GSNOR1 的 mRNA 表达相对于对照增加，而与对照相比，单独用 SA 和 NaCl 处理的植物中 OsNOA 的表达水平更高。与对照相比，除了在 2 DAT 外，单独或组合处理的植物中 OsNR 的 mRNA 表达均降低。总之，目前的研究结果表明，SA 可以调节水稻中 NaCl 诱导的氧和氮活性物种的产生。
