Submitted to: Journal of Invertebrate Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 6, 1997
Publication Date: N/A
Interpretive Summary: Chemicals applied to fields to control insect pests can be very effective. However, there are environmental and health concerns over their use. We are researching the potential of fungi, formulated with agricultural commoditities such as cornstarch and corn flour, as effective bioinsecticides which are environmentally friendly. Certain species of fungi have been known for more than a century to infect only insects. Commercial use of fungi as biological insecticides has been hindered, in part, because formulations of fungi are unacceptable. We tested several agricultural commodities as formulation ingredients for one potential fungal pathogen. Shelf life was increased through the addition of some of these materials. This information will be useful to companies interested in commercializing bioinsecticides, as well as scientists involved in formulation science.
Technical Abstract: The successful use of fungal entomopathogens for biological control of insects or weeds depends, in part, on the development of suitable formulations. Thirty eight formulations, based mostly on agricultural commodities such as cornstarch and corn flour were mixed at different concentrations with liquid medium containing blastospores and hyphal fragments of the fungal entomopathogen Paecilomyces fumosoroseus. Formulations were freeze-dried, and blastospore survival based on colony forming units was determined at different periods of time. The freeze-drying process reduced the viability of blastospores, with 22 formulations having over 75% survival which indicates that blastospores are tolerant to desiccation. Some of the formulation ingredients appear to provide protection over extended periods of time, with higher numbers of blastospores surviving than in the control, which consisted of blastospores lyophilized in spent medium.