Trichoderma spp. are beneficial soil microorganisms used in sustainable agriculture for their ability to enhance plant performance under different environments. However, Trichoderma-activated mechanisms that help plants to cope with water stress are still not completely defined. We investigated morpho-physiological, biochemical and transcriptomic responses to PEG-induced short severe water stress in Trichoderma longibrachiatum-inoculated and non-inoculated Solanum lycopersicum. Trichoderma had significant biostimulation effects on the plant and, after stress, allowed recovery of growth and photosynthesis to the levels of unstressed plants. Whole-transcriptome analysis was carried out after 1 day of 15 % PEG treatment in 22-day Trichoderma-inoculated and non-inoculated plants. Under non-stress conditions, Trichoderma triggered an extensive transcriptional reprogramming, specifically modulating the expression of classes of transcription factors and of genes involved in photosynthesis, antioxidant defences and maintenance of a juvenile state. Though the effects of water stress were predominant, mainly boosting transcription of stress-responsive genes, pre-treatment with Trichoderma specifically affected genes involved in mitigation of stress damage. Our findings provide new insights into the plant interplay with Trichoderma, useful to further exploit rhizosphere fungi for the improvement of plant performance under limiting environments.

木霉属 是用于可持续农业的有益土壤微生物，因为它们能够在不同环境下提高植物性能。然而，帮助植物应对水分胁迫的木霉激活机制仍未完全确定。我们研究了长柄木霉接种和未接种的茄属植物对 PEG 诱导的短期严重水分胁迫的形态生理、生化和转录组学响应。木霉属对植物有显着的生物刺激作用，并且在胁迫后，使生长和光合作用恢复到未受胁迫的植物水平。在 15% PEG 处理 22 天的接种和未接种木霉的植物中进行 1 天后的全转录组分析。在非压力条件下，木霉引发广泛的转录重编程，特别是调节转录因子类别和参与光合作用、抗氧化防御和维持幼年状态的基因的表达。虽然水分胁迫的影响是主要的，主要是促进胁迫响应基因的转录，用木霉预处理特别影响参与减轻压力损害的基因。我们的发现为植物与木霉的相互作用提供了新的见解，有助于进一步利用根际真菌来改善植物在限制环境下的表现。