A Paecilomyces fumosoroseus mutant over-producing chitinase displays enhanced virulence against Bemisia tabaci
Tóm tắt
A Paecilomyces fumosoroseus strain was mutagenized by u.v. Among 200 colonies, one mutant (M84), showed a large and stable chitin hydrolysis-halo. Glucose consumption and biomass production were similar for M84 and the parental strain. Chitinase was inducible by chitin and repressed by glucose in both strains but, when they were grown on minimal medium plus colloidal chitin as sole carbon source, the parental and M84 strains yielded 198 and 690 μmol N-acetylglucosamine, respectively. This results indicate that the mutant strain synthesized a chitinase with a higher activity. Bioassays against Bemisia tabaci nymph, showed that M84 incited a 2-fold higher incidence of disease compared to the parental strain.
Tài liệu tham khảo
Altre, J.A., Vandenberg, J.D. & Cantone, F.A. 1999 Pathogenicity of Paecilomyces fumosoroseus isolates to diamondback moth, Plutella xylostella: correlation with spore size, germination speed, and attachment to cuticle. Journal of Invertebrate Pathology 73, 332–338.
Brey, P.T., Latge, J.P. & Prevost, M.C. 1986 Intergumental penetration of the pea aphid, Acyrthosiphon pisium, by Conidiobolus obscurus (Entomophthoraceae). Journal of Invertebrate Pathology 48, 34–41.
El-Sayed, G.N., Coudron, T.A., Ignoffo, C.M. & Riba, G. 1989 Chitinolytic activity and virulence associated with native and mutant isolates of an entomopathogenic fungus Nomuraea rileyi. Journal of Invertebrate Pathology 54, 394–403.
Gupta, S.C., Leathers, T.D., El-Sayed, G.N. & Ignoffo, C.M. 1994 Relationships among enzyme activities and virulence parameters in Beauveria bassiana infections of Galleria mellonella and Trichoplusia ni. Journal of Invertebrate Pathology 64, 13–17.
Kang, S.C., Park, S. & Lee, D.G. 1999 Purification and characterization of a novel chitinase from the entomopathogenic fungus, Metarhizium anisopliae. Journal of Invertebrate Pathology 73, 276–281.
Miller, G.L. 1959 Use of dinitrosalicylic acid reagent for determination of reducing sugars. Analytical Chemistry 31, 426–428.
Nava-Camberos, U. 1998 Relaciones densidad-rendimiento y estimación de umbrales económicos para la mosquita blanca de la hoja plateada (Bemisia argentifoli Bellows & Perring) In Temas selectos para el manejo integrado de la mosquita blanca, eds. Pacheco-Covarrubias, J.J., Pacheco-Mendívil, F. INIFAP, Mexico, pp. 73–91.
Sampson, M.N. & Gooday, G.W. 1998 Involvement of chitinases of Bacillus thuringiensis during pathogenesis in insects. Microbiology 144, 2189–2194.
Smith, R.J. & Grula, E.A. 1983 Chitinase is an inducible enzyme in Beauveria bassiana. Journal of Invertebrate Pathology 42, 319–326.
Stansly, P.A., Schuster, D.J. & Liu, T.X. 1997 Apparent parasitism of Bemisia argentifolii (Homoptera: Aleyrodidae) by aphelinidae (Hymenoptera) on vegetable crops and associated weeds in south Florida. Biological Control 9, 49–57.
St. Leger, R.J., Joshi, L., Bidochka, M.J., Rizzo, N.W. & Roberts, D.W. 1996 Characterization and ultrastructural localization of chitinases from Metarhizium anisopliae, M. flavoviride, and Beauveria bassiana during fungal invasion of host (Manduca sexta) cuticle. Applied and Environmental Microbiology 62, 907–912.
Ulhoa, C.J. & Peberdy, J.F. 1991 Regulation of chitinase synthesis in Trichoderma harzianum. Journal of General Microbiology 137, 2163–2169.
United States Department of Agriculture. 1995 Whitefly knowledgebase. http://gnv.ifas.ufl.edu/~ent2/wfly/.
Vasseur, V., Arigoni, F., Andersen, H., Defago, G., Bompeix, G. & Seng, J.M. 1990 Isolation and characterization of Aphanocladium album chitinase-overproducing mutants. Journal of General Microbiology 136, 2561–2567.
Wraight, S.P., Carruthers, R.I., Jaronski, S.T., Bradley, C.A., Garza, C.J. & Galaini-Wraight, S. 2000 Evaluation of the entomopathogenic fungi Beauveria bassiana and Paecilomyces fumosoroseus for microbial control of the silverleaf whitefly, Bemisia argentifolii. Biological Control 17, 203–217.