Fungal Pathogens for Biocontrol of Thrips in Greenhouses Progress Report — March 1992
Date March 1, 1992
Title of Project Fungal Pathogens for Biocontrol of Thrips in Greenhouses
Institution where work is being conducted University of Vermont
Amount of Endowment Grant $ 7,000
Covering Period 1/1/92 to 12/31/92
Anticipated Date of Project Completion/Final Report Project is on-going, but an interim report will be submitted 1/1/93
Individual(s) Conducting Project:
(List Project Leader First)
Bruce L. Parker - Title Research Director
Telephone Number 802-658-4453
Michael Brownbridge - Title Research Professor
Fungal Pathogens for Biocontrol of Thrips in Greenhouses
Bruce L. Parker and Michael Brownbridge
University of Vermont
- A. Objectives of Research:
- 1. Select the most effective fungal strains for control of western flower thrips(WFT), among isolates of Verticillium lecanii, Beauveria bassiana and Metarhizium
anisopliae.
- 2. Conduct small-scale efficacy trials on thrips-infested chrysanthemums andsoil using promising fungal strains.
- 3. Monitor the survival and maintenance of an effective level of inoculum insoil treated with fungal pathogens.
- B. Summary of Work Conducted Since Project’s Inception:
- Our aim is to develop insect-killing fungal pathogens, native to the USA, forcontrol of greenhouse pests. When the research proposal was originally submitted
to the AFE, we had demonstrated that 14 indigenous fungal isolates, representing
three different species, were pathogenic to WFT. On completion of a non-AFE
funded piece of research, we were able to identify numerous other fungi, isolated
from Vermont forest soils and insects, with the potential capacity to kill WFT. These
are being screened for activity to WFT.
- New artificial rearing methods for production of WFT are being developed.Although not funded by the AFE, this will provide us with a constant, even-aged
supply of thrips for our laboratory work and assist us greatly in the pursuit of our
research objectives.
- C. Results to Date:
- An additional 10 fungal isolates have been shown to be highly pathogenic toWFT: 3 M. anisopliae; 2 B. bassiana, 3 Paecilomyces farinosus; and 1 P. lilacinus,
increasing our arsenal of promising candidate strains for possible use against this
devastating pest species. By having a broad base of pathogen types, we will be able
to identify the best and most practical strains for control of WFT. Quantitative
bioassays wil permit the selection of the most effective strains for evaluation in Obj.
2 and 3.
- An article has been prepared for grower magazines to inform growers of ournew research initiative and to publicize the support of the endowment. Poster and
oral presentations have also been made at VT grower meetings to further stimulate
a grass-roots interest in our research.
- Of further interest, but not directly funded by the AFE, is that preliminary trialshave shown that, some of the VT insect-fungi are also pathogenic to green peach
aphid, indicating that such biocontrol agents could have a broad spectrum of activity
against a variety of floral and greenhouse pests.
- D. Future Plans Covered by the Endowment Grant:
- On completion of Obj. 1, we will be able to identify the most lethal fungalstrains for further testing. On-plant and in-soil trials will give us essential information
on the efficacy of the different strains and the insect stage and environment which
can most effectively be targeted for control.
- E. Anticipated Benefits for Floral Industry:
- We believe that fungal pathogens have tremendous potential for the biocontrolof WFT and other serious pests. Their development will provide a practical,
effective, environmentally safe and economically viable component for pest
management in the floriculture industry.
