Viability of Metarhizium anisopliae (Metschnikoff) Sorokin Conidia in Vegetable Oil Formulations and Their Virulence on the Termite Microcerotermes diversus Silvestri (Isoptera: Termitidae)

In this study formulations were prepared by emulsion of different vegetable oils (sunflower corn rosemary olive sesame and walnut) of Metarhizium anisopliae (Metschnikoff) Sorokin conidia. Control formulation was also prepared and germination of fungal conidia in all formulations was assessed. Results showed that control and olive oil formulations had the highest average conidial germination while the sesame oil formulation had the lowest germination. Effect of four concentrations (108 107 106 and 105 conidia/ml) of these formulations were applied against populations of Microcerotermes diversus Silvestri (Isoptera: Termitidae) termites. Due to high mortality rate in the first three concentrations the treatment with 105 conidia/ml was used in comparisons. The highest mean percent termite mortality (91.25%) was obtained with the sesame oil formulation and the lowest (58.33%) with control formulation. The lowest LT50 (2.38 days) occurred with the sesame oil formulation while the control formulation had the greatest LT50 (15.9 days). The lowest calculated LC50 (1.7  104 conidia/ml) was also for sesame oil formulation.