A survey of fungal pathogens of aphids from South Africa, with special reference to cereal aphids

Surveys of entomopathogenic fungi of aphids in South Africa were conducted from 1995 through 1998. A total of eight species of fungi known to infect and kill aphid hosts were collected, including six Entomophthorales and two Hyphomycetes. The Entomophthorales included Pandora neoaphidis, Conidiobolus thromboides, C. obscurus, C. coronatus, Entomophthora planchoniana, and Neozygites fresenii. The two Hyphomycetes collected were Beauveria bassiana and Verticillium lecanii. P. neoaphidis, C. thromboides, C. obscurus, and E. planchoniana are considered first reports from South Africa, and V. lecanii was for the first time isolated from an insect host in South Africa. Most findings of entomopathogenic fungi were from cereal aphids including six species from the Russian wheat aphid, Diuraphis noxia. In both the summer and the winter rainfall regions of South Africa, fungi recorded from the cereal aphid complex were found from early spring through early summer. Findings from nonagricultural aphid hosts were usually made during late-summer through late-fall with two recordings during the winter months of June and July. The number of species of fungi collected reflects a great diversity in the aphid-pathogenic flora from South Africa.