Department of Botany, University of Peshawar, Peshawar, Pakistan.
Department of Botany, Bacha Khan University, Charsadda, Pakistan.
PLoS One. 2021 Aug 6;16(8):e0248200. doi: 10.1371/journal.pone.0248200. eCollection 2021.
Water being a vital part of cell protoplasm plays a significant role in sustaining life on earth; however, drastic changes in climatic conditions lead to limiting the availability of water and causing other environmental adversities. α-tocopherol being a powerful antioxidant, protects lipid membranes from the drastic effects of oxidative stress by deactivating singlet oxygen, reducing superoxide radicals, and terminating lipid peroxidation by reducing fatty acyl peroxy radicals under drought stress conditions. A pot experiment was conducted and two groups of lentil cultivar (Punjab-2009) were exposed to 20 and 25 days of drought induced stress by restricting the availability of water after 60th day of germination. Both of the groups were sprinkled with α-tocopherol 100, 200 and 300 mg/L. Induced water deficit stress conditions caused a pronounced decline in growth parameters including absolute growth rate (AGR), leaf area index (LAI), leaf area ratio (LAR), root shoot ratio (RSR), relative growth rate (RGR), chlorophyll a, b, total chlorophyll content, carotenoids, and soluble protein content (SPC) which were significantly enhanced by exogenously applied α-tocopherol. Moreover, a significant increase was reported in total proline content (TPC), soluble sugar content (SSC), glycine betaine (GB) content, endogenous tocopherol levels, ascorbate peroxidase (APX), catalase (CAT) peroxidase (POD) and superoxide dismutase (SOD) activities. On the contrary, exogenously applied α-tocopherol significantly reduced the concentrations of malondialdehyde (MDA) and hydrogen peroxide (H2O2). In conclusion, it was confirmed that exogenous application of α-tocopherol under drought induced stress regimes resulted in membrane protection by inhibiting lipid peroxidation, enhancing the activities of antioxidative enzymes (APX, CAT, POD, and SOD) and accumulation of osmolytes such as glycine betaine, proline and sugar. Consequently, modulating different growth, physiological and biochemical attributes.
水是细胞质的重要组成部分，对维持地球上的生命起着重要作用；然而，气候条件的剧烈变化导致可利用水资源的限制，并造成其他环境逆境。α-生育酚作为一种强大的抗氧化剂，通过使单线态氧失活、减少超氧自由基、减少脂肪酸过氧自由基来终止脂质过氧化，从而保护脂膜免受氧化应激的剧烈影响。进行了盆栽试验，将两组豌豆品种（旁遮普 2009 年）在发芽后 60 天暴露于 20 和 25 天的干旱诱导胁迫下，通过限制水分的可用性来限制水分的可用性。两组都喷洒了 100、200 和 300mg/L 的α-生育酚。诱导的水分亏缺胁迫条件导致生长参数明显下降，包括绝对生长率（AGR）、叶面积指数（LAI）、叶面积比（LAR）、根冠比（RSR）、相对生长率（RGR）、叶绿素 a、b、总叶绿素含量、类胡萝卜素和可溶性蛋白质含量（SPC），这些参数均显著提高。此外，总脯氨酸含量（TPC）、可溶性糖含量（SSC）、甘氨酸甜菜碱（GB）含量、内源性生育酚水平、抗坏血酸过氧化物酶（APX）、过氧化氢酶（CAT）过氧化物酶（POD）和超氧化物歧化酶（SOD）活性均显著增加。相反，外源施加的α-生育酚显著降低了丙二醛（MDA）和过氧化氢（H2O2）的浓度。总之，证实了在干旱诱导胁迫条件下外源施加α-生育酚可通过抑制脂质过氧化来保护细胞膜，增强抗氧化酶（APX、CAT、POD 和 SOD）的活性，并积累甘氨酸甜菜碱、脯氨酸和糖等渗透物，从而调节不同的生长、生理和生化特性。
