Drought and heat stress are two dominant abiotic stress factors that often occur simultaneously in nature causing oxidative damage in plants and thus decline in yield. The present study was conducted to examine the γ-aminobutyric acid (GABA)-induced heat and drought tolerance in sunflower through physiological, biochemical and molecular analysis. The results showed that drought and heat stress triggered oxidative stress as revealed by enhanced level in hydrogen peroxide, malondialdehyde and electrolyte leakage. Moreover, the photosynthetic attributes such as; photosynthetic rate, stomatal conductance and quantum efficiency declined when subjected to drought and heat stress. In this study, GABA treatment effectively alleviated the drought and heat-induced stress as reflected by significantly higher levels of proline, soluble sugar and total protein content. Besides, the data also revealed the direct relationship between antioxidant enzyme activities (superoxide dismutase; peroxidase This article is protected by copyright. All rights reserved.

中文翻译：

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γ-氨基丁酸（GABA）通过调节向日葵（Helianthus annuus L.）的生理、生化和分子途径减轻干旱和热应激

干旱和热胁迫是自然界中经常同时发生的两种主要的非生物胁迫因素，导致植物氧化损伤，从而导致产量下降。本研究旨在通过生理、生化和分子分析来检测 γ-氨基丁酸 (GABA) 诱导的向日葵耐热耐旱性。结果表明，干旱和热应激引发了氧化应激，如过氧化氢、丙二醛和电解质泄漏水平升高所揭示。此外，光合属性，如; 当受到干旱和热胁迫时，光合速率、气孔导度和量子效率下降。在这项研究中，GABA 处理有效缓解了干旱和热诱导的胁迫，表现为脯氨酸水平显着升高，可溶性糖和总蛋白质含量。此外，数据还揭示了抗氧化酶活性（超氧化物歧化酶；过氧化物酶）之间的直接关系本文受版权保护。保留所有权利。