Evaluation the efficiency of mixing some oils with entomopathogenic fungus Beauveria bassiana against Aphis craccivora

Document Type : Original Article

Author

Plant Protection Research Institute, Agricultural Research Center, Dokki 12611, Giza, Egypt.

Abstract

The entomopathogenic fungus, Beauveria bassiana, is a commonly used mycoinsecticide. Meanwhile, B. bassiana is highly susceptible to the damaging effects of solar radiation (specially UV) which in turn reducing its insecticidal efficacy. This report presents initial results from laboratory studies aimed at assessing the potential of oil formulations to enhance efficacy of B. bassiana against aphid pests. Four oil formulations are used under investigation in this study; orange, star, sunflower, and soybean oil. Aphid population reduction % were determined 3, 5, 7, and 10 days after treatment using Abbott’s formula. The results revealed that oil formulations have significantly enhanced the aphicidal efficacy of B. bassiana by about 1.6 folds compared to aqueous preparations. This improvement may be contributed to the increased adhesion of the fungus on the insect’s cuticle and homogenous distribution of fungal spores on the leaf surface as well as providing a protecting layer against UV-light.
In conclusion, oil formulations (horticulture /mineral oils) are one of the most promising technologies for enhancing efficacy of the entomopathogenic B. bassiana against aphids. mixing orange oil with B. bassiana has exerted a considerable mortality percentage against A. craccivora.

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