International Journal of Pathogen Research

Aims: The study aims to evaluate the efficacy of Trichoderma koningii in combination with Arbuscular mycorrhizal fungus (Glomus claroideum) application in the control of Meloidogyne arenaria (Neal) infecting fluted pumpkin (Telfairia occidentalis) in Calabar.

Study design: The experiment was laid out in a completely randomized design (CRD) with three replications.

Methodology: One gram of T. koningii at different inoculum load; 2.50×10⁷ CFU/g, 1.38×10⁷ CFU/g, 1.20×10⁷ CFU/g and 9.0×10⁶ CFU/g of millet were applied in combination with Arbuscular mycorrhizal fungus at 50, 100 and 300 spores/plant. Unamended soil served as control. Two weeks old Pumpkin plants were inoculated with (5,000) second stage larvae of M. arenaria in a heat sterilized soil. Number of galls, number of leaves, number of pods, gall index, and fresh pod weight/plant were recorded. 

Results: Fluted pumpkin was highly susceptible to M. arenaria with gall index rated 5.00 (G. I) without Arbuscular mycorrhizal fungus or T. koningii. Increase in Arbuscular mycorrhizal fungus concentration and inoculum load of T. koningii applied singly significantly (P = .05) reduced root galling of M. arenaria in the plant. The combination of T. koningii at 2.50 × 10⁷ CFU/g of millet with 300 spores per plant significantly reduced the susceptibility rating of pumpkin to (GI = 2.00). The combination of T. koningii with Arbuscular mycorrhizal fungus significantly (P = .05) enhanced growth, number of pods, fresh pod and root weight/plant. The highest fresh pod yield (98.14/g plant) was obtained on 2.50×10⁷ CFU /g of T. koningii in combination with 300 spores per plant of Arbuscular mycorrhizal fungus.

Conclusion: Increase in Arbuscular mycorrhizal fungus and T. koningii when applied singly, significantly reduced root galling. Combined application of Arbuscular mycorrhizal fungus at 300 spores/plant, with T. koningii at 2.50×10⁷ CFU/g of millet significantly reduced root galling than single application.