Efficacy of botanical and microbial fungal bio-pesticide against a key pest of Helicoverpa armigera (Hubner)
Nilofer Syed, Ashok Kumar, Sujoita Purohit, Arti Prasad
Objective: To study the histopathological approach of Botanical biopesticides Lantana camera and microbial fungus Beauveria bassiana to reveal the mode of action on insect tissues. Methods: In our experiment, both biopesticides botanical Lantana camera and microbial entomopathogenic fungus Beauveria bassiana (Balsamo) were applied on Helicoverpa armigera (Hubner) larva. The whole-body section of untreated and treated larvae was taken to observe their effect on various tissues by histopathological techniques. Results: Larvae were treated with the highest dose of 1. 0 ml leaf and flower extract and 0.250 x 108 conidia/ml. Hematoxylin, Eosin, and Mallory triple stain were used for the histopathological protocol. Slanting section of the body exposed noticeable change in a variety of tissues. Extract affected the complete loss of peritrophic membrane, disorganized columnar epithelium, structural and fat bodies, and damaged integument. The fungus also targeted to cuticular fraction, which was well obvious by injured exocuticle, endocuticle, and statement of conidia in big amounts on the outside surface as well as in the crypts of the cuticular wall. The overall effect brought about the liquefaction of the body tissues making the infected larvae turgid which upon slight disturbance, ruptured releasing the infected conidia into the environment. Conclusion: The histopathological studies have revealed that integument is the main target tissue for the action of both biopesticides. However, it was also observed in the histomicrographs that extensive tissue destruction occurred in the body and epithelium of the insect.
Nilofer Syed, Ashok Kumar, Sujoita Purohit, Arti Prasad. Efficacy of botanical and microbial fungal bio-pesticide against a key pest of Helicoverpa armigera (Hubner). International Journal of Entomology Research, Volume 7, Issue 2, 2022, Pages 93-100