Effects of Plant Phenolic Compounds and Bacillus Thuringiensis Subsp. Kurstaki on Immune Responses and Antioxidant Enzyme Activities of Hyphantria Cunea (Drury, 1773) (Lepidoptera: Arctiidae) Larvae

Abstract

Studies on ecological immunology are crucial in determining how the immune responses of insects against both abiotic and biotic factors are affected. In this study, the effects of phenolic compounds in plants on the immune responses and antioxidant enzyme activities of Hyphantria cunea larvae infected by Bacillus thuringiensis subsp. kurstaki were investigated. For this purpose, phenolic compounds present in mulberry, apple, walnut and plum plants (preferred by H. cunea and having economic importance) were determined. H. cunea culture was obtained from larvae collected in Bafra, Samsun in 2019. It was found that the haemocyte counts of both control and infected larvae fed in the walnut plant containing the highest gallotannin amount were the highest. It was found that catechin and rutin flavonoids caused minimum phenoloxidase activity. It was determined that the highest superoxide dismutase activities were in the plum-fed groups and the lowest catalase activities were in the larvae fed in the walnut groups both in the control and infected groups. As a result, it was determined that immune responses and antioxidant enzyme activities can be changed due to both phenolic compounds present in plants and infection.