Gupta Sneha Vinay Kumar, Smith Penelope M C, Natera Siria H A, Roessner Ute
School of BioSciences, University of Melbourne, Parkville, VIC, Australia.
School of Life Sciences, La Trobe University, Bundoora, VIC, Australia.
Front Plant Sci. 2022 Aug 2;13:908853. doi: 10.3389/fpls.2022.908853. eCollection 2022.
One of the most important environmental factors impacting crop plant productivity is soil salinity. Fungal endophytes have been characterised as biocontrol agents that help in plant productivity and induce resistance responses to several abiotic stresses, including salinity. In the salt-tolerant cereal crop barley ( L.), there is limited information about the metabolites and lipids that change in response to inoculation with fungal endophytes in saline conditions. In this study, gas chromatography coupled to mass spectrometry (GC-MS) and LC-electrospray ionisation (ESI)-quadrupole-quadrupole time of flight (QqTOF)-MS were used to determine the metabolite and lipid changes in two fungal inoculated barley genotypes with differing tolerance levels to saline conditions. The more salt-tolerant cultivar was Vlamingh and less salt tolerant was Gairdner. strain T-22 was used to treat these plants grown in soil under control and saline (200 mM NaCl) conditions. For both genotypes, fungus-colonised plants exposed to NaCl had greater root and shoot biomass, and better chlorophyll content than non-colonised plants, with colonised-Vlamingh performing better than uninoculated control plants. The metabolome dataset using GC-MS consisted of a total of 93 metabolites of which 74 were identified in roots of both barley genotypes as organic acids, sugars, sugar acids, sugar alcohols, amino acids, amines, and a small number of fatty acids. LC-QqTOF-MS analysis resulted in the detection of 186 lipid molecular species, classified into three major lipid classes-glycerophospholipids, glycerolipids, and sphingolipids, from roots of both genotypes. In Cultivar Vlamingh both metabolites and lipids increased with fungus and salt treatment while in Gairdner they decreased. The results from this study suggest that the metabolic pathways by which the fungus imparts salt tolerance is different for the different genotypes.
影响作物生产力的最重要环境因素之一是土壤盐分。真菌内生菌已被鉴定为生物防治剂，有助于提高植物生产力，并诱导植物对包括盐分在内的多种非生物胁迫产生抗性反应。在耐盐谷类作物大麦（L.）中，关于在盐胁迫条件下接种真菌内生菌后代谢物和脂质变化的信息有限。在本研究中，采用气相色谱-质谱联用（GC-MS）和液相色谱-电喷雾电离（ESI）-四极杆-四极杆飞行时间（QqTOF）-MS来确定两种对盐胁迫耐受性不同的真菌接种大麦基因型中的代谢物和脂质变化。耐盐性较强的品种是Vlamingh，耐盐性较弱的是Gairdner。用T-22菌株处理在对照和盐胁迫（200 mM NaCl）条件下土壤中生长的这些植物。对于这两个基因型，暴露于NaCl的真菌定殖植物比未定殖植物具有更大的根和地上部生物量以及更好的叶绿素含量，定殖的Vlamingh表现优于未接种的对照植物。使用GC-MS的代谢组数据集总共包含93种代谢物，其中74种在两种大麦基因型的根中被鉴定为有机酸、糖、糖酸、糖醇、氨基酸、胺和少量脂肪酸。LC-QqTOF-MS分析从两种基因型的根中检测到186种脂质分子种类，分为三大类脂质——甘油磷脂、甘油脂和鞘脂。在Vlamingh品种中，代谢物和脂质都随着真菌和盐处理而增加，而在Gairdner品种中则减少。本研究结果表明，真菌赋予耐盐性的代谢途径因不同基因型而异。
