Naz R, Gul F, Zahoor S, Nosheen A, Yasmin H, Keyani R, Shahid M, Hassan M N, Siddiqui M H, Batool S, Anwar Z, Ali N, Roberts T H
Department of Biosciences, COMSATS University Islamabad, Islamabad, Pakistan.
Department of Environmental Sciences, COMSATS University Islamabad, Islamabad, Pakistan.
Plant Biol (Stuttg). 2022 Jun;24(4):684-696. doi: 10.1111/plb.13374. Epub 2021 Dec 8.
Recent changes in climate have reduced crop productivity throughout much of the world. Drought and heat stress, particularly in arid and semi-arid regions, have seriously affected barley production. This study explored the separate and interactive effects of silicon (Si) and hydrogen sulphide (H S) on plant growth and mitigation of the adverse effects of heat stress (DS) and drought stress (HS) in a barley pot experiment. The impacts of simultaneous DS + HS were more severe than individual stresses due to increased ROS production, malondialdehyde (MDA) content and higher electrolyte leakage (EL), thereby leading to reduced water, protein and photosynthetic pigment content. Exogenously applied Si and H S alleviated the DS-, HS- and DS + HS-induced effects on barley by reducing ROS production, MDA and EL. A single application of H S or Si + H S increased plant biomass under all stress conditions, which can be ascribed to higher Si accumulation in barley shoots. A single application of Si or H S significantly increased plant biomass. However, Si + H S was the most effective treatment for metabolite accumulation and elevating activity of antioxidant enzymes to prevent toxicity from oxidative stress. This treatment also modulated osmolyte content, enhanced antioxidant activity and regulated the stress signalling-related endogenous hormones, abscisic acid (ABA) and indole acetic acid (IAA). Exogenous treatments regulated endogenous H S and Si and resulted in higher tolerance to individual and combined drought and heat stress in barley.
近期气候变化已降低了世界大部分地区的作物生产力。干旱和热胁迫，尤其是在干旱和半干旱地区，已严重影响了大麦生产。本研究在大麦盆栽试验中探究了硅（Si）和硫化氢（H₂S）对植物生长的单独及交互作用，以及对热胁迫（DS）和干旱胁迫（HS）不利影响的缓解作用。由于活性氧（ROS）生成增加、丙二醛（MDA）含量升高和电解质渗漏（EL）增加，同时发生的DS + HS的影响比单一胁迫更为严重，从而导致水分、蛋白质和光合色素含量降低。外源施用Si和H₂S通过减少ROS生成、MDA和EL，减轻了DS、HS和DS + HS对大麦的诱导效应。在所有胁迫条件下，单独施用H₂S或Si + H₂S均增加了植物生物量，这可归因于大麦地上部更高的Si积累。单独施用Si或H₂S显著增加了植物生物量。然而，Si + H₂S对于代谢物积累和提高抗氧化酶活性以防止氧化应激毒性是最有效的处理。该处理还调节了渗透溶质含量，增强了抗氧化活性，并调节了与胁迫信号相关的内源激素脱落酸（ABA）和吲哚乙酸（IAA）。外源处理调节了内源H₂S和Si，并使大麦对单独和复合的干旱和热胁迫具有更高耐受性。
