Evaluation of Endophytic Beauvaria bassiana as a Targeted Insecticide in Tomato

Abstract

A targeted insecticide treatment has great value in agriculture because it would mitigate insect damage while causing no harm to non-harmful insects, especially pollinators. Beauvaria bassiana is an endophyte which has been shown to improve plant growth and is a known insect pathogen. It was hypothesized that the combination of these two traits would make B. bassiana a potential targeted insecticide. Two tomato (Solanum lycoperscicum) varieties, Early Girl and Heinz 1706-BG, were inoculated with Beauvaria bassiana. The Early Girl variety was tracked to assess plant-fungal interactions, while the Heinz variety was inoculated with beet armyworm larvae (Spodoptera exigua) to examine effects of Beauveria on herbivory. Our results show that B. bassiana was transferred from the leaf tissue to the beet armyworm larvae, infecting and killing some insects, and slowing insect damage. Our results also show some indication that B. bassiana of pathogenic, rather than mutualistic, interaction with the Early Girl variety of tomato.