Submitted to: Southwestern Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 11, 2001
Publication Date: December 15, 2001
Citation: GODFREY, K., STEINKRAUS, D., MCGUIRE, M.R. FUNGAL PATHOGENS OF THE COTTON AND GREEN PEACH APHIDS IN THE SAN JOAQUIN VALLEY.. SOUTHWESTERN ENTOMOLOGIST. 2001.
Interpretive Summary: The cotton aphid is a serious pest of cotton in the U. S. and can exist in a range of crops. The green peach aphid can also reach damaging levels in several crops. To reduce the reliance on chemical pesticides, a program was initiated to determine if natural enemies (insect specific parasites and pathogens) could be released into existing aphid populations to reduce overall populations. However, before this can be done, it is important to know what is already present in the aphid populations. There are several fungi that infect and kill only aphids. In our surveys, we found three separate species of fungi but in very low numbers. Another fungus, found in the southeast U. S. is currently being considered for release in California. This work is of primary importance to other scientists but, eventually could have impact on cotton farming operations.
The native fungi attacking cotton aphid and green peach aphid were surveyed routinely for two years and intermittently for another year in the San Joaquin Valley. A low incidence of fungal infection was found, and the fungi were most prevalent in the cooler, wetter times of the year. Three fungi, Pandora neoaphidis, Conidiobolus obscurus, and Entomophthora planchoniana were identified from the aphids. Additionally, vegetative stages of unidentified entomophthoralean fungi were also recovered. A pictorial guide to these fungi is given.