title: Aspergillus flavus impairs antioxidative enzymes of Sternochetus mangiferae during mycosis.
abstract: Insects depend upon cuticular, humoral and cellular defenses to resist mycosis. However, entomopathogenic fungi through co-evolution have developed mechanisms to counter such defenses. Although a plethora of mechanisms of mycosis by entomopathogenic fungi are well-established, studies on the impairment of insects' antioxidative enzymes during mycosis remain elusive. Here, we used the interaction of Sternochetus mangiferae and its associated entomopathogenic fungus, Aspergillus flavus, as a model to validate our hypothesis. Uninfected insects were exposed to fungal spores for infection to occur. We observed symptoms of mycosis within 48 h of incubation period. Biochemical studies on antioxidative enzymes namely catalase, peroxidase and phenoloxidase, in infected and uninfected insects revealed decreased activity of these enzymes. It appears that A. flavus disables the host's antioxidative enzyme system that plays a crucial role in elimination of oxidative toxins produced during mycosis.
authors.affiliation: Division of Entomology and Nematology, Indian Institute of Horticultural Research, Hessarghatta Lake Post, Bangalore 560089, India. Electronic address: jaiinsect@gmail.com.
authors.forename: Kamala  P D
authors.initials: K
authors.lastname: Jayanthi
authors.affiliation: Division of Entomology and Nematology, Indian Institute of Horticultural Research, Hessarghatta Lake Post, Bangalore 560089, India.
authors.forename: Arthikirubha
authors.initials: A
authors.lastname: Ayyasamy
authors.affiliation: Division of Entomology and Nematology, Indian Institute of Horticultural Research, Hessarghatta Lake Post, Bangalore 560089, India.
authors.forename: Vivek
authors.initials: V
authors.lastname: Kempraj
authors.affiliation: Division of Entomology and Nematology, Indian Institute of Horticultural Research, Hessarghatta Lake Post, Bangalore 560089, India.
authors.forename: Ravindra M
authors.initials: RM
authors.lastname: Aurade
authors.affiliation: Division of Soil Science, Indian Institute of Horticultural Research, Hessarghatta Lake Post, Bangalore 560089, India.
authors.forename: Selvakumar
authors.initials: S
authors.lastname: Govindan
authors.affiliation: Division of Entomology and Nematology, Indian Institute of Horticultural Research, Hessarghatta Lake Post, Bangalore 560089, India.
authors.forename: Abraham
authors.initials: A
authors.lastname: Verghese
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001231:Aspergillus flavus / Q000378:metabolism / Q000502:physiology*; D001517:Coleoptera / Q000201:enzymology / Q000382:microbiology*; D004198:Disease Susceptibility
chemical_list: D000975:Antioxidants
keywords: Aspergillus flavus; Sternochetus mangiferae; antioxidative enzymes; entomopathogenic fungi; mango stone weevil