An ecological assessment of Isaria fumosorosea compared to a neonicotinoid treatment for regulating invasive ficus whitefly

Authors: AVERY, PASCO - University Of Florida; KUMAR, VIVEK - University Of Florida; SKVARCH, EDWARD - University Of Florida; MANNION, CATHARINE - University Of Florida; POWELL, CHARLES - University Of Florida; McKenzie, Cindy; OSBORNE, LANCE - University Of Florida

Submitted to: The Journal of Fungi
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/25/2019
Publication Date: 5/4/2019
Citation: Avery, P.B., Kumar, V., Skvarch, E.A., Mannion, C.M., Powell, C.A., McKenzie, C.L., Osborne, L.S. 2019. An ecological assessment of Isaria fumosorosea compared to a neonicotinoid treatment for regulating invasive ficus whitefly. The Journal of Fungi. 5:36
DOI: https://doi.org/10.3390/jof5020036

Interpretive Summary: The ficus whitefly, Singhiella simplex (Singh), is an invasive species that has become a major pest in Florida feeding on Ficus shrubs and trees. This exotic species of whitefly endemic to the South Asian region i.e., Myanmar, China and India was first discovered in the United States in 2007 from Miami-Dade County in Florida, and since then it has become a problem for homeowners, residential community managers, landscapers, growers, businesses and government officials throughout the State. A severe ficus whitefly infestation occurred in a residential community on a Ficus benjamina hedge in Fort Pierce, Florida and needed immediate attention because of the constant leaf drop. In our efforts to support the residents, we planned a pilot study to evaluate the efficacy of the entomopathogenic fungi, Isaria fumosorosea (strain Apopka-97) contained in the formulated biopesticide product, PFR-97® 20% WDG™ against ficus whitefly. We also, evaluated the effect of fungal and neonicotinoid treatments on the natural enemies and the naturally occurring enzootic fungal entomopathogens present in the affected area. Both treatments provided significant reduction in the whitefly population compared to control and were compatible with the natural enemies present. Results from this pilot study suggest there is much potential for using repeat applications of the fungal biopesticide, PFR-97™ as a foliar spray compared to a neonicitionid as a soil drench for managing Singhiella simplex on Ficus species for = 28 days.

Technical Abstract: A pilot study was conducted on a weeping fig, Ficus benjamina shrub hedge to determine the efficacy of a fungal biopesticide, PFR-97™ which contains blastospores of Isaria fumosorosea, and a neonicotinoid treatment (Admire Pro™) applied against the invasive ficus whitefly pest, Singhiella simplex (Singh). Post treatment, an ecological assessment of the study was conducted by observing the impact of the fungal biopesticide and neonicotinoid treatment on natural enemies, e.g. predators, parasitoids and enzootic fungal pathogens occurring in the whitefly-infested hedge. Both treatments provided significant reduction in the whitefly population compared to control and were compatible with the natural enemies present. Various natural enemies including fungal entomopathogens were identified associated with the whitefly population infesting the weeping fig hedge. The parasitoids, Encarsia protransvena Viggiani and Amitus bennetti Viggiani & Evans combined parasitized a similar mean number of whitefly nymphs in both treatments and control; however, the number parasitized decreased over time. Natural enzootic fungal entomopathogens infecting and isolated from the ficus whitefly nymphs were Isaria fumosorosea, Purpureocillium lilacinum and Lecanicillium, Aspergillus and Fusarium species. Results from this pilot study suggest there is much potential for using repeat applications of the fungal biopesticide, PFR-97™ as a foliar spray compared to a neonicitionid as a soil drench for managing S. simplex on Ficus species for = 28 days.