The symbiotic fungi improve the growth parameters of plants under environmental stresses. To investigate the effect of endophytic fungi under water stress, we investigated the symbiosis of two new isolated endophytic fungi Curvularia spicifera and Gibberella thapsina from Chenopodiaceae species (Kochia stellaris and Chenopodium album) versus mycorrhizal (Funneliformis mosseae) and Serendipita indica fungi with wheat plants under water stress. The experiment was conducted as completely randomized design with three replicates per treatment. The treatments included soil water stress (field capacity (FC) and 50% FC) and fungus (inoculation and non-inoculation). The two new endophytic fungi could colonize wheat root and significantly improved the growth parameters. Curvularia spicifera inoculation resulted to high fresh and dry shoot biomass, proline and protein content and K/Na ratio but this endophyte increased content of electrolyte leakage. Curvularia spicifera-inoculated plants had more activity of the enzyme than S. indica-inoculated plants in ascorbate peroxidase (APX) under water stress while S. indica-inoculated plants showed higher concentration of nutrients. Serendipita indica-inoculated and C. spicifera-inoculants plants did not show significant differences in content of chlorophyll. The contents of proline and proteins as well as the activity of catalase in G. thapsina-inoculated plants were higher than F. mosseae. We found that C. spicifera and G. thapsina improve production of biomass and metabolites in shoot of wheat and they can change water availability in soil. According to compare the functional groups of inoculated fungi, we suggest that the two endophytes could significantly reprogram the growth of wheat plants during stress conditions with unknown mechanisms.
