Fungal Endophytes Promote Tomato Growth and Enhance Drought and Salt Tolerance.

In a search for efficient fungal endophytes that can promote crop production and/or increase crop tolerance to abiotic stress, we isolated and tested various species harbored by wild plants. Sixty-seven endophytic fungal isolates were obtained from drought stressed, poor soil habitats, and inland high salt areas. We extensively tested the roles of sp. and sp. isolates in improving tomato growth and yield. Under greenhouse and field trails, sp. and sp. endophytes proved effective in conferring positive benefits to tomatoes placed under stress as well as under normal growing conditions. sp. conferred tolerance to tomatoes placed under drought stress in addition to enhancing overall plant growth and fruit yield in comparison to non-symbiotic plants under drought stress. sp. conferred tolerance to tomatoes placed under 300 mM salinity stress in addition to enhancing root biomass in comparison to non-symbiotic plants. Both endophytes proved efficient in enhancing plant growth, stress tolerance, recovery, and fruit yield under optimal experimental conditions in comparison to non-symbiotic plants. Field testing of tomato yield showed increased yield of symbiotic tomatoes compared to non-symbiotic ones. This data suggests that both sp. and sp. share a promising potential for improving future agricultural production, particularly with the projected changes in climate in the future.