State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources, China University of Mining and Technology (Beijing), Beijing, China.
Institute of Ecological Environment Restoration in Mine Areas of West China, Xi'an University of Science and Technology, China.
Physiol Plant. 2023 Nov-Dec;175(6):e14054. doi: 10.1111/ppl.14054.
The influence of dark septate endophytic (DSE) on the antioxidant activity of Astragalus membranaceus var. mongholicus under heat stress was investigated. A. membranaceus plants, with or without DSE inoculation, were grown at 28°C for 8 weeks in a greenhouse and subsequently subjected to heat stress conditions (42°C) in an artificial climate chamber. DSE inoculation significantly decreased the malondialdehyde (MDA) content during the initial three days of heat stress. The activities of superoxide dismutase (SOD) and peroxidase (POD) of A. membranaceus leaves were significantly enhanced by DSE inoculation under heat stress, with SOD activities being 63-81% higher than in other treatments. The glutathione (GSH) and putrescine (Put) contents accumulated significantly on the third day under heat stress with DSE inoculation. Additionally, the contents of soluble sugars and proline (Pro) exhibited significant increases on the seventh day of heat stress and were 33-55% and 81-83% higher than in other treatments, respectively. Three-way ANOVA shows that DSE inoculation under heat stress exerted a significant impact on MDA. Multivariate linear regression and structural equality modelling (SEM) further show that the interaction among these antioxidants significantly decreased MDA content and maintained the normal function of cell membranes. In conclusion, DSE inoculation enhanced the heat tolerance of A. membranaceus by boosting its antioxidant capacity and reducing MDA production. This study highlights the potential of utilizing DSE as a strategy to enhance plant heat tolerance.
研究了深色有隔内生真菌（DSE）对热应激下蒙古黄芪抗氧化活性的影响。将接种或不接种 DSE 的蒙古黄芪植物在温室中于 28°C 下生长 8 周，然后在人工气候室中进行热应激条件（42°C）处理。DSE 接种在热应激的最初三天内显著降低了丙二醛（MDA）的含量。在热应激下，DSE 接种显著增强了黄芪叶片中超氧化物歧化酶（SOD）和过氧化物酶（POD）的活性，SOD 活性比其他处理高 63-81%。在 DSE 接种下，GSH 和腐胺（Put）的含量在热应激的第三天显著积累。此外，可溶性糖和脯氨酸（Pro）的含量在热应激的第七天显著增加，分别比其他处理高 33-55%和 81-83%。三因素方差分析表明，DSE 接种在热应激下对 MDA 有显著影响。多元线性回归和结构相等模型（SEM）进一步表明，这些抗氧化剂之间的相互作用显著降低了 MDA 含量并维持了细胞膜的正常功能。总之，DSE 接种通过增强抗氧化能力和降低 MDA 产生来提高黄芪的耐热性。本研究强调了利用 DSE 作为提高植物耐热性的策略的潜力。
