Fusarium equiseti is an effective plant growth-promoting fungi that induce systemic disease resistance in plants. However, the role of F. equiseti in regulating salt stress response and the underlying mechanisms remain largely unknown. Here, we investigated the effect of F. equiseti Z7 strain on the growth and salt stress response in perennial ryegrass. Additionally, the role of Z7 in regulating the abundance, composition, and structure of native microbial communities in the rhizosphere soil was determined. We observed that Z7 could produce indole-3-acetic acid (IAA) and siderophores. Hence, Z7 inoculation further enhanced plant growth and salt tolerance in perennial ryegrass. Inoculating Z7 increased K⁺ and decreased Na⁺ in plant tissues. Z7 inoculation also enhanced soil quality by reducing soluble salt and increasing available phosphorus. Moreover, inoculating Z7 altered the compositions of bacterial and fungal communities in the rhizosphere soil. For instance, beneficial bacterial genera, such as Flavobacterium, Enterobacter, Agrobacterium, and Burkholderiales were dominantly enriched in Z7-inoculated soil. Interestingly, the relative abundance of these genera showed significantly positive correlations with the fresh weight of perennial ryegrass. Our results demonstrate that Z7 could remarkably promote plant growth and salt tolerance by regulating ion homeostasis in plant tissues and microbial communities in the rhizosphere soil. This study provides a scientific foundation for applying microbes to improve plant growth under extreme salt stress conditions.

Fusarium equiseti是一种有效的植物生长促进真菌，可诱导植物产生系统性抗病性。然而，木贼镰刀菌在调节盐胁迫反应中的作用及其潜在机制在很大程度上仍然未知。在这里，我们研究了F. equiseti Z7 菌株对多年生黑麦草生长和盐胁迫反应的影响。此外，还确定了 Z7 在调节根际土壤中原生微生物群落的丰度、组成和结构方面的作用。我们观察到 Z7 可以产生吲哚-3-乙酸 (IAA) 和铁载体。因此，Z7 接种进一步增强了多年生黑麦草的植物生长和耐盐性。接种 Z7 增加了 K ⁺并减少了 Na ⁺在植物组织中。Z7 接种还通过减少可溶性盐和增加有效磷来提高土壤质量。此外，接种 Z7 改变了根际土壤中细菌和真菌群落的组成。例如，黄杆菌属、肠杆菌属、农杆菌属和伯克氏菌属等有益细菌属在Z7接种的土壤中显着富集。有趣的是，这些属的相对丰度与多年生黑麦草的鲜重呈显着正相关。我们的研究结果表明，Z7 可以通过调节植物组织和根际土壤微生物群落中的离子稳态来显着促进植物生长和耐盐性。该研究为应用微生物改善植物在极端盐胁迫条件下的生长提供了科学依据。