Mycorrhizal Fungal Effects on Plant Growth, Osmolytes, and CsHsp70s and CsPIPs Expression in Leaves of Cucumber under a Short-Term Heat Stress

作者：Xinran Liu, Zi-Yi Rong, Xiao Tian, Abeer Hashem, Elsayed Fathi Abd Allah, Ying‐Ning Zou, Qiang‐Sheng Wu · 发表于：Plants · 年份：2023 · DOI：10.3390/plants12162917 · 被引用次数：20 · 研究领域：Mycorrhizal Fungi and Plant Interactions、Plant Stress Responses and Tolerance、Plant Parasitism and Resistance

Arbuscular mycorrhizal (AM) fungi enhance plant stress tolerance, but it is unclear whether AM fungi affect heat tolerance in cucumbers. This study aimed to analyze how an AM fungus, Diversispora versiformis, affected growth, chlorophyll, five osmolytes, and plasma membrane intrinsic proteins (PIPs) and heat shock protein 70 (Hsp70) gene expression in cucumber leaves after a short-term (80 h) heat stress. Heat treatment significantly reduced root AM fungal colonization rate (0.26 folds). Heat treatment also distinctly suppressed plant height, stem diameter, and biomass, whereas AM fungal inoculation improved these growth variables as well as the chlorophyll index, with the benefit being more obvious under heat than under no-heat stress conditions. Heat treatment triggered differential changes in osmolytes (sucrose, fructose, and betaine) of inoculated and uninoculated cucumbers, whereas inoculation with AM fungus significantly raised leaf sucrose, fructose, glucose, betaine, and proline levels when compared to non-AM fungal inoculation. Heat treatment increased the expression of two (CsPIP1;6 and CsPIP2;1) of eight CsPIPs in inoculated and uninoculated plants, whereas AM fungal inoculation up-regulated the expression of CsPIP1;6, CsPIP2;1, and CsPIP2;6 under heat stress conditions. Hsp70s expressed differently in inoculated and uninoculated plants under heat versus no-heat stress, with 6 of 11 CsHsp70s down-regulated in inoculated plants. Under heat stress conditions, AM fung...