Screening Endophytic Fungi in Cotton for Effects Against Root-Knot Nematodes

Many fungal endophytes have been shown to engage in beneficial mutualisms with their hosts. Several studies in multiple crops including cotton have demonstrated the potential for fungal endophytes to have antagonistic effects on parasitic nematodes when present in planta. We evaluated 67 different strains of candidate beneficial fungal endophytes originally isolated from cotton for antagonistic effects against the root-knot nematode, Meloidogyne incognita, in greenhouse assays. Endophyte treatments were applied using a fungal biomass seed coating. Treatment and control seeds were planted in sterilized sand. Seedlings were inoculated with 1,500 M. incognita eggs at the first true-leaf stage and nematode infection was measured by quantifying galls at 21 days after egg inoculation. Multiple fungal endophyte isolates significantly reduced root-knot nematode galling relative to controls and constitute good candidates for more rigorous evaluation.