Zhang Wei, Yin Xilong, Feng Zengwei, Liu Xiaodi, Zhu Fengwa, Zhu Honghui, Yao Qing
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (South China), Ministry of Agriculture and Rural Affairs, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Horticulture, South China Agricultural University, Guangzhou, China.
Key Laboratory of Agricultural Microbiomics and Precision Application (MARA), Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Key Laboratory of Agricultural Microbiome (MARA), State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China.
Front Plant Sci. 2024 Sep 20;15:1452202. doi: 10.3389/fpls.2024.1452202. eCollection 2024.
Drought stress poses increasingly serious threats to agricultural production in the era of global climate change. Arbuscular mycorrhizal (AM) fungi are well-recognized biostimulants promoting plant tolerance to drought stress. Lipids are indispensable for AM fungal colonization, however, the involvement of lipid metabolism in the drought tolerance conferred by AM fungi is largely unknown. In this study, we inoculated (L.) with DAOM197198 under no drought stress, medium drought stress and severe drought stress, with non-inoculation under respective treatments as control. Results indicated that AM fungal inoculation significantly promoted the drought tolerance of (L.), with the effect size decreasing along with drought severity. Moreover, the effect size was significantly related to arbuscule abundance. Fatty acid profiling showed that the arbuscule abundance was determined by the AM-specific phospholipids (PLs), whose biosynthesis and delivery were inhibited by drought stress as revealed by qRT-PCR of , and /. More interestingly, AM fungal inoculation increased the lipid allocation to total PLs and the unsaturation rate of total neutral lipids (NLs), probably indicating the involvement of non-AM-specific lipids in the increased drought tolerance. Taken together, our results demonstrate that lipid metabolism in AM mediates the increased drought tolerance conferred by AM fungal inoculation, with AM-specific and non-AM-specific lipids functioning therein in different ways.
在全球气候变化时代，干旱胁迫对农业生产构成了日益严重的威胁。丛枝菌根（AM）真菌是公认的能促进植物耐旱性的生物刺激剂。脂质对于AM真菌的定殖是不可或缺的，然而，脂质代谢在AM真菌赋予的耐旱性中的作用在很大程度上尚不清楚。在本研究中，我们在无干旱胁迫、中度干旱胁迫和重度干旱胁迫下，用DAOM197198接种（L.），各处理下未接种作为对照。结果表明，接种AM真菌显著提高了（L.）的耐旱性，效应大小随干旱严重程度的增加而降低。此外，效应大小与丛枝丰度显著相关。脂肪酸谱分析表明，丛枝丰度由AM特异性磷脂（PLs）决定，qRT-PCR检测发现，干旱胁迫抑制了其生物合成和转运。更有趣的是，接种AM真菌增加了脂质向总PLs的分配以及总中性脂质（NLs）的不饱和度，这可能表明非AM特异性脂质参与了耐旱性的提高。综上所述，我们的结果表明，AM中的脂质代谢介导了接种AM真菌所赋予的耐旱性增加，其中AM特异性和非AM特异性脂质以不同方式发挥作用。
