Abstract

Gibberellic acid (GA₃) application has been shown to affect salinity tolerance through modulating oxidative stress processes. Moreover, paclobutrazol (PBZ) as a GA₃ biosynthetic inhibitor has been reported to mitigate salt stress in some plant species. In this study, we investigated how GA₃ and its inhibitor, PBZ, reduced the negative effects of salt stress in leaves of sweet sorghum (Sorghum bicolor [L.] Moench cv. Sofra) by changing content of osmoprotectants and activity of ROS-scavenging enzymes. After germination, seedlings of sorghum were cultured in Hoagland solution containing sodium chloride (0, 100 and 200 mM NaCl) supplemented with GA₃ and PBZ for 12 days. The results were analyzed using principal component analysis (PCA) to identify the best target(s) under salinity, GA₃ and PBZ in sweet sorghum. Based on PCA, our findings showed that PBZ and GA₃ treatments acted by different mechanisms under salinity. GA₃ primarily affected the activity of superoxide dismutase (SOD), peroxidase (POD), glutathione reductase (GR), catalase (CAT), and glycine betaine (GB) contents under salinity, whereas PBZ treatment had significant influence on the activity of Δ¹-pyrroline-5-carboxylate synthetase (P5CS), proline content, activity of CAT, GR, and total antioxidant capacity in leaves of sweet sorghum plants.

中文翻译：

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赤霉素和多效唑对甜高粱离体盐胁迫诱导的氧化应激反应的作用

摘要

赤霉素（GA ₃）的使用已证明可通过调节氧化应激过程影响盐度耐受性。此外，据报道多效唑（PBZ）作为GA ₃生物合成抑制剂可减轻某些植物物种的盐胁迫。在这项研究中，我们研究了GA ₃及其抑制剂PBZ如何通过改变渗透保护剂的含量和清除ROS的活性来减轻甜高粱（Sorghum bicolor [L.] Moench cv。Sofra）叶片盐胁迫的负面影响。酶。发芽后，将高粱幼苗在含有氯化钠（0、100和200 mM NaCl）和GA _3的Hoagland溶液中培养。和PBZ 12天。使用主成分分析（PCA）对结果进行了分析，以确定甜高粱中盐度，GA ₃和PBZ下的最佳目标。基于PCA，我们的发现表明在盐度下PBZ和GA ₃处理的作用机理不同。GA ₃主要影响盐度下的超氧化物歧化酶（SOD），过氧化物酶（POD），谷胱甘肽还原酶（GR），过氧化氢酶（CAT）和甘氨酸甜菜碱（GB）的活性，而PBZ处理对Δ的活性有显着影响甜高粱植物叶片中的^1-吡咯啉-5-羧酸合成酶（P5CS），脯氨酸含量，CAT，GR活性和总抗氧化能力。