Sarker Umakanta, Oba Shinya
Department of Genetics and Plant Breeding, Faculty of Agriculture, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh.
Laboratory of Field Science, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan.
Front Plant Sci. 2020 Oct 16;11:559876. doi: 10.3389/fpls.2020.559876. eCollection 2020.
An investigation was carried out to elucidate growth, anatomical, physiological, and major ROS detoxification pathways involved in the tolerance of under salinity stress. Both VA14 and VA3 varieties exhibited the reduction in relative water content (RWC), photosynthetic pigments, growth, increased electrolyte leakage (EL), and leaf anatomy adaptation under salinity stress, whereas VA14 was well adapted and performed better compared to VA3. Higher ROS accumulation was demonstrated in the sensitive variety (VA3) in comparison to the tolerant variety (VA14). Salinity stress changed the cellular antioxidant pool by increasing total carotenoids, ascorbate, proline, total polyphenol content (TPC), total flavonoid content (TFC), and total antioxidant capacity (TAC) in both varieties. Although a higher increment was demonstrated in the tolerant variety, the proline increment was much more pronounced in the sensitive variety. Non-enzymatic antioxidant, ascorbate, carotenoids, TPC, TFC, TAC, and antioxidant enzymes SOD and APX were noted to be a major HO detoxifier in the tolerant variety, where there is a comparatively lower HO load. It was complemented by GPOX and CAT activity at a comparatively higher HO load (in the sensitive variety). SOD contributed to the dismutation of superoxide radical (SOR) both in the tolerant and sensitive varieties; however, it greatly contributed to the dismutation of SOR in the tolerant variety. The increase in SOD, ascorbate, and APX makes it predominantly evident that SOD and the AsA-GSH cycle had greatly contributed to quench reactive oxygen species (ROS) of the tolerant variety of .
开展了一项调查，以阐明盐胁迫下[植物品种名称未明确给出]耐受性所涉及的生长、解剖学、生理学以及主要的活性氧解毒途径。VA14和VA3两个品种在盐胁迫下均表现出相对含水量（RWC）降低、光合色素减少、生长受抑制、电解质渗漏（EL）增加以及叶片解剖结构适应，然而与VA3相比，VA14适应性更好且表现更佳。与耐性品种（VA14）相比，敏感品种（VA3）中活性氧积累更高。盐胁迫通过增加两个品种中的总类胡萝卜素、抗坏血酸、脯氨酸、总多酚含量（TPC）、总黄酮含量（TFC）和总抗氧化能力（TAC）改变了细胞抗氧化库。尽管耐性品种中这些指标的增幅更高，但脯氨酸在敏感品种中的增幅更为显著。非酶抗氧化剂、抗坏血酸、类胡萝卜素、TPC、TFC、TAC以及抗氧化酶超氧化物歧化酶（SOD）和抗坏血酸过氧化物酶（APX）被认为是耐性品种中主要的羟基自由基（HO）解毒剂，该品种中HO负荷相对较低。在相对较高的HO负荷下（敏感品种中），谷胱甘肽过氧化物酶（GPOX）和过氧化氢酶（CAT）的活性起到了补充作用。SOD在耐性和敏感品种中均有助于超氧阴离子自由基（SOR）的歧化；然而，它在耐性品种中对SOR歧化的贡献更大。SOD、抗坏血酸和APX的增加使得SOD和抗坏血酸 - 谷胱甘肽循环对耐性品种中活性氧（ROS）的淬灭作用显著增强这一点变得尤为明显。
