Salinity is a major abiotic stress threatening crop production. Root-derived bacteria (RDB) are hypothesized to play a role in enhancing plant adaptability to various stresses. However, it is still unclear whether and how plants build up specific RDB when challenged by salinity. In this study, we measured the composition and variation in the rhizosphere and endophyte bacteria of salt-sensitive (SSs) and salt-resistant (SRs) plants under soil conditions with/without salinity. The salt-induced RDB (both rhizobiomes and endophytes) were isolated to examine their effects on the physiological responses of SSs and SRs to salinity challenge. Moreover, we examined whether functional redundancy exists among salt-induced RDB in enhancing plant adaptability to salt stress. We observed that although SSs and SRs recruited distinct RDB and relevant functions when challenged by salinity, salt-induced recruitment of specific RDB led to a consistent growth promotion in plants regardless of their salinity tolerance capacities. Plants employed a species-specific strategy to recruit beneficial soil bacteria in the rhizosphere rather than in the endosphere. Furthermore, we demonstrated that the consortium, but not individual members of the salt-induced RDB, provided enduring resistance against salt stress. This study confirms the critical role of salt-induced RDB in enhancing plant adaptability to salt stress.

盐度是威胁作物生产的主要非生物胁迫。假设根源细菌 (RDB) 在增强植物对各种胁迫的适应性方面发挥作用。然而，目前尚不清楚植物在受到盐度挑战时是否以及如何建立特定的 RDB。在这项研究中，我们测量了在有/无盐度的土壤条件下盐敏感 (SSs) 和耐盐 (SRs) 植物的根际和内生细菌的组成和变化。分离盐诱导的 RDB（根瘤菌和内生菌）以检查它们对 SS 和 SR 对盐度挑战的生理反应的影响。此外，我们检查了盐诱导的 RDB 在增强植物对盐胁迫的适应性方面是否存在功能冗余。我们观察到，尽管 SSs 和 SRs 在受到盐度挑战时会募集不同的 RDB 和相关功能，但盐诱导的特定 RDB 募集会导致植物持续促进生长，而不管它们的耐盐能力如何。植物采用物种特异性策略在根际而不是根际招募有益的土壤细菌。此外，我们证明了联合体，而不是盐诱导的 RDB 的个别成员，提供了对盐胁迫的持久抵抗力。该研究证实了盐诱导的 RDB 在增强植物对盐胁迫的适应性方面的关键作用。植物采用物种特异性策略在根际而不是根际招募有益的土壤细菌。此外，我们证明了联合体，而不是盐诱导的 RDB 的个别成员，提供了对盐胁迫的持久抵抗力。该研究证实了盐诱导的 RDB 在增强植物对盐胁迫的适应性方面的关键作用。植物采用物种特异性策略在根际而不是根际招募有益的土壤细菌。此外，我们证明了联合体，而不是盐诱导的 RDB 的个别成员，提供了对盐胁迫的持久抵抗力。该研究证实了盐诱导的 RDB 在增强植物对盐胁迫的适应性方面的关键作用。