Due to its contribution to plant drought tolerance, arbuscular mycorrhizae (AM) may play an important role in the revegetation of degraded pastures in semi-arid and arid regions. Salsola laricina, an important forage plant in Iran, belongs to predominantly non-mycotrophic Chenopodiaceae, but field observations suggest that it forms functional mycorrhizae. We therefore, established a greenhouse experiment to test the mycorrhizal response of this species at four levels of soil moisture and to determine the contribution of AM to the drought tolerance of this species. The plants were grown in sterilized soil and either left non-inoculated or inoculated with four AM fungal isolates originating from an S. laricina field site to investigate also the functional variability of sympatric AM fungal species. Root colonization of S. laricina by AM fungi was found in all the inoculated treatments, and mycorrhizae clearly improved the plants' growth and P uptake. The mycorrhizal responses, i.e., the differences between mycorrhizal and non-mycorrhizal plants, were most pronounced at the lowest soil moisture level of 25% field capacity, which strongly suggests that mycorrhiza contributes to the drought tolerance of S. laricina. Differential effects of the four inoculated AM fungal isolates, independent of their root colonization levels, indicate differential compatibility of the isolates with this host plant species. The findings of the study have important implications for the revegetation of degraded pastures with S. laricina, as they show that AM should be considered in this process.