Protein and isozyme patterns among isolates of Beauveria brongniartii with different virulence to European cockchafer larvae (Melolontha melolontha L.)

Abstract

It was the purpose of this study to elucidate whether sodium dodecyl sulfate‐polyactylamide gel electrophoresis (SDS‐PAGE) of soluble proteins and isozyme analysis of intracellular enzymes are useful methods to distinguish between 31 Beauveria brongniartii isolates of different virulence to Melolontha melolontha larvae. Cluster and principle coordinate analysis of data from soluble proteins demonstrated a high level of intraspecific variation and little correlation with virulence to M. melolontha larvae. The isozymes of the esterase, acid phosphatase and malate dehydrogenase showed high activity and gave consistent band resolution, resulting in 18 different enzyme types, whereas the enzyme systems of the alkaline phosphatase, catalase, glutamate oxalacetate transaminase, peroxidase and superoxide dismutase were not suitable for further evaluation. Levels of intraspecific variation after isozyme analysis were lower than in total protein analysis. Although two of the four B. brongniartii isolates with the lowest virulence against M. melolontha larvae differed in their enzyme patterns from the other isolates, a clear distinction between groups of different virulent isolates was not possible. Thus, analysis of the isozyme patterns of intracellular enzymes could only be a first step in selecting more promising B. brongniartii pathotypes for development as biocontrol agents.

Virulence of Beauveria brongniartii and B. bassiana against Schizonycha affinis white grubs and adults (Coleoptera: Scarabaeidae)

“…However, in screening bioassays, the commercially available B. bassiana isolate (BB444) was the most virulent of the entomopathogens tested on T. molitor, while a number of the isolates of B. brongniartii were not highly virulent. The observed differences in virulence of B. brongniartii isolates were not surprising as others have shown that isolates of B. brongniartii are host specific (Vestergaard et al 2003;Traugott et al 2005) and that genetically closely related isolates varied in their virulence against different scarab hosts (Reineke and Zebitz 1996;Cravanzola et al 1997;Sharma et al 1999;Darwish et al 2000), or had genetic variations in specific regions, that is 28s rDNA group-1 introns, that appeared to be correlated with pathogenicity (Neuv eglise et al 1997). We further hypothesized that isolates of B. brongniartii sharing a haplotype may have similar virulence towards a particular host, which was validated in adult T. molitor bioassays.…”

“…; Traugott et al. ) and that genetically closely related isolates varied in their virulence against different scarab hosts (Reineke and Zebitz ; Cravanzola et al. ; Sharma et al.…”

Biochemical and molecular characteristics of indigenous strains of the entomopathogenic fungusBeauveria bassianaof Central India

“…The isolates showed high intraspecific variation and little association were observed between genotypic class and virulence to European cockchafer (Melolontha melolontha ) larvae (Reineke & Zebitz 1996). A high natural variability in populations of B. bassiana was shown by St.…”

“…Within species, strains often may be quite host-specific (Bidochka 1995). The biodiversity of the entomopathogenic fungal genetic resources have been studied using morphological, biochemical (Poprawski et al 1988;St Leger et al 1992b;Reineke & Zebitz 1996;Castrillo & Brooks 1998) or molecular markers (Fegan et al 1993;Bridge et al 1997;Cantone et al 1998;Castrillo et al 1999).…”

Relationships among activities of extracellular enzyme production and virulence against Helicoverpa armigera in Beauveria bassiana

“…Todorova et al [14] studied the heterogeneity of two isolates of entomopathogenic fungus B. bassiana using SDS -PAGE technique and the strains were characterized depending upon the protein profiles. Reineke and Zebitz [29] characterized the mycelial proteins of four isolates of B. brongniartii and reported a high level of intraspecific variation. Jordao et al [15] also characterized five isolates of B. bassiana by SDS -PAGE and showed some differences among the isolates studied, though there was no difference in virulence of B. bassiana against Cosmopolites sordidus.…”