Department of Agronomy, University of Agriculture, Faisalabad, 38040, Pakistan.
Department of Seed Science and Technology, University of Agriculture, Faisalabad, 38040, Pakistan.
Mol Biol Rep. 2022 Jun;49(6):5611-5624. doi: 10.1007/s11033-022-07535-6. Epub 2022 May 26.
Salinity stress (SS) is a serious detrimental factor for crop growth and productivity and its intensity it is continuously increasing which is posing serious threat to global food security. Hydrogen peroxide (HO) priming has emerged as an excellent strategy to mitigate the adverse impacts of SS. However, the role of HO priming in mitigating the salinity induced toxicity is not fully explored.
Therefore, in this context the present study was conducted in complete randomized design (CRD) in factorial combination to determine the impact of HO priming on germination, growth, physiological and biochemical traits, osmo-regulating compounds, hormonal balance and ionic homeostasis. The experiment was based on different levels of SS; control, 6 and 12 dS m SS and priming treatments, control and HO priming (2%). Salinity stress significantly reduced the growth, leaf water status (- 15.55%), calcium (Ca), potassium (K) and magnesium (Mg) accumulation and increased malondialdehyde (MDA: + 29.95%), HO (+ 21.48%) contents, osmo-regulating compounds (proline, soluble sugars), indole acetic acid (IAA), anti-oxidant activities (ascorbate peroxidase: APX, catalase: CAT, peroxidase: POD and ascorbic acid: AsA) and accumulation of sodium (Na) and chloride (Cl). HO priming effectively reduced the effects of SS on germination and growth and strengthen the anti-oxidant activities through reduced MDA (- 12.36%) and HO (- 21.13%) and increasing leaf water status (16.90%), soluble protein (+ 71.32%), free amino acids (+ 26.41%), proline (+ 49.18%), soluble sugars (+ 71.02%), IAA (+ 57.59%) and gibberlic acid (GA) (+ 21.11%). Above all, HO priming reduced the massive entry of noxious ions (Na and Cl) while increased the entry of Ca, K and Mg thus improved the plant performance under SS.
In conclusion HO priming was proved beneficial for improving maize growth under SS thorough enhanced anti-oxidant activities, photosynthetic pigments, leaf water status, accumulation of osmo-regulating compounds, hormonal balance and ionic homeostasis.
盐胁迫（SS）是作物生长和生产力的严重有害因素，其强度不断增加，对全球粮食安全构成严重威胁。过氧化氢（HO）引发已成为减轻 SS 不利影响的绝佳策略。然而，HO 引发减轻盐诱导毒性的作用尚未得到充分探索。
因此，在这种情况下，本研究在完全随机设计（CRD）的因子组合中进行，以确定 HO 引发对萌发、生长、生理生化特性、渗透调节化合物、激素平衡和离子动态平衡的影响。实验基于不同的 SS 水平；对照、6 和 12 dS m SS 和引发处理、对照和 HO 引发（2%）。盐胁迫显著降低了生长、叶片水分状态（-15.55%）、钙（Ca）、钾（K）和镁（Mg）的积累，并增加了丙二醛（MDA：+29.95%）、HO（+21.48%）含量、渗透调节化合物（脯氨酸、可溶性糖）、吲哚乙酸（IAA）、抗氧化活性（抗坏血酸过氧化物酶：APX、过氧化氢酶：CAT、过氧化物酶：POD 和抗坏血酸：AsA）和钠（Na）和氯（Cl）的积累。HO 引发有效地减轻了 SS 对萌发和生长的影响，并通过降低 MDA（-12.36%）和 HO（-21.13%）和增加叶片水分状态（16.90%）、可溶性蛋白（+71.32%）、游离氨基酸（+26.41%）、脯氨酸（+49.18%）、可溶性糖（+71.02%）、IAA（+57.59%）和赤霉素（GA）（+21.11%）来增强抗氧化活性。最重要的是，HO 引发减少了有害物质离子（Na 和 Cl）的大量进入，同时增加了 Ca、K 和 Mg 的进入，从而改善了 SS 下植物的性能。
总之，HO 引发通过增强抗氧化活性、光合色素、叶片水分状态、渗透调节化合物的积累、激素平衡和离子动态平衡，被证明有利于提高玉米在 SS 下的生长。
