Beauveria bassiana and Paecilomyces fumosoroseus are two entomopathogenic fungi that infect the silver leaf whitefly (SLWF). We found that B. bassiana germinated poorly on cuticle of SLWF nymphs, yet previous studies have shown P. fumosoroseus to have high germination on the cuticle. To determine if the cuticular lipid that heavily coats nymphs might be inhibiting germination, the wax ester was extracted from several nymphs and applied to nitro-cellulose membranes. These membranes were then treated with fungal spores, and spore germination was determined after the membranes were soaked in either water or nutrient broth for 12 hours. Both fungi were inhibited by the insect lipid when soaked in broth, but B. bassiana was more sensitive than P. fumosoroseus. In the absence of nutrients, the lipid enhanced P. fumosoroseus germination, perhaps serving as a nutrient source. Such an effect was not seen with B. bassiana.
Species 1: Homopertera Aleyrodidae Bemisia argentifolii (silverleaf whitefly)
Keywords: Beauveria, Paecilomyces
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA