Exploration and evaluation of root-associated endophytes against Meloidogyne incognita infecting tomato

The fungal endophytes play a key role in habitat adaptation of plants resulting in enhanced plant performance and withstand against biotic and abiotic stresses in the environment. The present study was conducted to isolate root-associated fungal endophytes from cultivated crops and evaluated for their efficacy against Meloidogyne incognita infecting tomato plants. Total 262 fungal root endophytes were isolated from 14 cultivated crops and classified and also grouped into 4 genera (Aspergillus sp., Penicillium sp., Fusarium sp., Trichoderma sp.) based on morphological structure. The colonization rate of these isolates ranged from 0 to 100%; Shannon’s index (H) is 0 to 1.37; Simpson (1-D) is 0 to 0.74 and Dominance (D) is 0.4 to 1. Antagonism evaluation of fungal endophytic isolates on M. incognita revealed that 5 isolates caused 100 per cent juveniles (J2) mortality, 14 isolates caused mortality in the range of 90-99 per cent, 12 isolates caused 75- 89 per cent mortality, and remaining 26 isolates caused <75 percent J2 mortality. The isolates that caused 100 per cent J2s mortality were molecularly characterized based on ITS-1 and ITS-2 gene nucleotide sequences and identified as Aspergillus flavipes, Penicillium murcianum, Fusarium oxysporum, Trichoderma asperellum and Trichoderma viride. Thesefungal root endophytic isolates possessed plant growth promotion traits, effectively parasitized the eggs of M. incognita and significantly reduced the infection in tomato.