Development of endo-rhizospheric fungal consortia to increase salt tolerance in crops

Abstract

Salinity and alkalinity are among the major environmental stresses affecting crop production, particularly in arid and semi-arid areas. Soil salinity affects mainly due to the excessive accumulation of toxic ions (Na+, Cl-, and SO42-), whereas alkaline soils are generally characterized by high concentrations of bicarbonate (HCO3-) and carbonate (CO32-) as well as high exchangeable Na+. Microbial biostimulants such as PGPR, and beneficial fungi (arbuscular mycorrhizal fungi (AMF) and Trichoderma spp. etc) are considered as promising tools to overcome the limitations of salinity and alkalinity on crop growth and productivity. Many PGPRs, AMF and Fungi like Trichoderma spp. strains can enhance crop tolerance to abiotic stresses including salt stress by increasing nutrient uptake through greater effective root area (for AMF) and better solubilization of nutrients (for PGPRs, Fungi like Trichoderma spp.), and by production of metabolites such as indole-3-acetic acid or auxin analogs. Hence, Rhizospheric and non-rhizospheric soil samples were collected for the isolation of salt tolerant fungi from different salt affected areas.