Vol. 10, Special Issue 1, Part E (2026)

Tomato productivity is severely constrained by root-knot nematode (Meloidogyne incognita), prompting the need for sustainable alternatives to chemical nematicides. Microbial biocontrol agents represent an eco-friendly strategy through direct antagonism of nematodes and enhancement of plant growth. In the present study, the efficacy of Trichoderma asperellum, Purpureocillium lilacinum, and Pseudomonas fluorescens was evaluated against M. incognita under in vitro and pot conditions. Cell-free culture filtrates significantly affected juvenile survival, with P. lilacinum inducing the highest mortality of second-stage juveniles (66%), followed by T. asperellum (52.6%) and P. fluorescens (45%). Pot experiments showed significant reductions in nematode infestation, with gall numbers reduced to 87.6 and 115.8 per plant in P. lilacinum and T. asperellum treatments, respectively, compared with 237.4 galls in the untreated control. Correspondingly, egg mass production declined markedly, reaching as low as 10.8 egg masses per plant under P. lilacinum. Biocontrol treatments also resulted in significant improvement in plant growth, with T. asperellum recording the highest shoot length (53.2 cm) and shoot biomass (141.96 g), compared with 21.96 cm and 57.72 g in the untreated control. Overall, the results demonstrate that these microbial biocontrol agents exert significant nematicidal effects while enhancing tomato growth, indicating their potential as sustainable components of integrated root-knot nematode management.