Progress 10/01/99 to 09/30/04
Outputs
One publication is in press and two are in preparation detailing the results of the research conducted under this project. Two publications deal with viburnum leaf beetle, a significant new pest of shrubs in the U.S.; one deals with impact of temperature on developmental processes of the pest, and the other deals with diurnal patterns of behavior. An additional publication dealing with degree-day models of insect emergence is also in preparation.
Impacts
The results of these studies will enable landscape and nursery managers to more precisely time control methods for major pests of landscape trees and shrubs. If significantly better predictors of arthropod emergence can be generated, it will increase the likelihood of adoption of growing degree-days or plant phenological indicators as aids to pest management, resulting in reduced use of pesticides. Population models of viburnum leaf beetle could be used in determining feasibility of biological control of this pest by predators or parasitoids.
Publications
- Weston, P. A. and M. D. Diaz. 2005. Thermal requirements and development of immature stages of viburnum leaf beetle, Pyrrhalta viburni (Coleoptera: Chrysomelidae). Environ. Entomol. (In press).
|
Progress 01/01/03 to 12/31/03
Outputs
Data for developing refined growing degree-day predictions and plant phenological indicators for arthropod developmental events had been collected, and data processing is continuing. We collected a significant amount of new data on some fundamental aspects of the biology of viburnum leaf beetle. We conclusively established the existence of three larval instars, and determined development time for each instar at three temperatures. The data also allowed us to calculate the threshold temperature for larval development. We determined the chilling requirement for eggs of viburnum leaf beetle, and thermal requirements for egg hatch after chilling requirements are met. We also obtained sound estimates for the reproductive potential of female beetles. These ecological characteristics will be helpful in the development of population models of viburnum leaf beetle. We are continuing to track the spread of viburnum leaf beetle (and other new introduced pests), and published our
findings detailing the spread of the insect in New York State, especially as it relates to the presence of its primary native host plant, arrowwood viburnum. This information will facilitate prediction regarding further spread of the pest, providing advanced warning to those in the expected areas of range expansion.
Impacts
The results of these studies will enable landscape and nursery managers to more precisely time control methods for major pests of landscape trees and shrubs. If significantly better predictors of arthropod emergence can be generated, it will increase the likelihood of adoption of growing degree-days or plant phenological indicators as aids to pest management, resulting in reduced use of pesticides. Population models of viburnum leaf beetle could be used in determining feasibility of biological control of this pest by predators or parasitoids.
Publications
- Weston, P. A. and Hoebeke, E. R. 2003. Spread of an introduced leaf beetle, Pyrrhalta viburni, in the northeast U.S. Proc. Entomol. Soc. Wash. 105:889-895.
|
Progress 01/01/02 to 12/31/02
Outputs
Work on the major objectives is at various degrees of completion. Data for developing refined growing degree-day predictions and plant phenological indicators for arthropod developmental events continue to be collected, and data processing is continuing. Work on characterizing attributes of viburnums responsible for resistance to viburnum leaf beetle is proceeding smoothly. Screening a diversity of crosses between two viburnums differing in susceptibility (originating from a collaborator in Wisconsin), we have found good evidence that resistance is mediated by a limited number of genes, and appears to be amenable to selection. We have refined bioassays for feeding by viburnum leaf beetle larvae and adults, and can now readily quantify viburnum susceptibility to this pest.
Impacts
The results of these studies will enable landscape and nursery managers able to more precisely time control methods for major pests of landscape trees and shrubs. If significantly better predictors of arthropod emergence can be generated, it will increase the likelihood of adoption of growing degree-days or plant phenological indicators as aids to pest management, resulting in reduced use of pesticides. Knowing which traits in resistant viburnums confer resistance to viburnum leaf beetle could be useful in breeding efforts to produce and maintain viburnums with less insecticide use.
Publications
- Weston, P. A., and G. Desurmont. 2002. Suitability of various species of Viburnum as hosts for Pyrrhalta viburni, an introduced leaf beetle. J. Environ. Hortic. 20(4): 224-227.
- Weston, P. A., B. C. Eshenaur, J. M. Baird, and J. S. Lamboy. 2002. Evaluation of pesticides for control of larvae of Pyrrhalta viburni (Coleoptera: Chrysomelidae), a new pest of viburnums. J. Environ. Hortic. 20(2): 82-85.
|
Progress 01/01/01 to 12/31/01
Outputs
Work on the major objectives is at various degrees of completion. Data for developing refined growing degree-day predictions and plant phenological indicators for arthropod developmental events continue to be collected, and data processing has begun. Work on characterizing attributes of viburnums responsible for resistance to viburnum leaf beetle is proceeding smoothly. Following earlier work classifying susceptibility/resistance of viburnums in the field, we examined representative viburnums in the laboratory and discovered that larvae of viburnum leaf beetle are able to complete development only on those species classified as "susceptible" in the field, although adults are able to feed on quite a few species, including some classified as "resistant."
Impacts
The results of these studies will enable landscape and nursery managers able to more precisely time control methods for major pests of landscape trees and shrubs. If significantly better predictors of arthropod emergence can be generated, it will increase the likelihood of adoption of growing degree-days or plant phenological indicators as aids to pest management, resulting in reduced use of pesticides. Knowing which traits in resistant viburnums confer resistance to viburnum leaf beetle could be useful in breeding efforts to produce and maintain viburnums with less insecticide use.
Publications
- Weston, P. A., J. M. Baird, and R. E. McNiel. 2001. Plant traits associated with resistance of viburnums to feeding by viburnum leaf beetle. HortScience 36(3): 553.
- Weston, P. A. 2001. Viburnum leaf beetle, Pyrrhalta viburni (Paykull). Regulatory Horticulture 27: 27-30.
- Weston, P. A., B. C. Eshenaur, and J. S. Lamboy. 2001. Control options for the viburnum leaf beetle. Yankee Grower 3(4): 11-13.
|
Progress 01/01/00 to 12/31/00
Outputs
Work on the major objectives is at various degrees of completion. Data for developing refined growing degree-day predictions and plant phenological indicators for arthropod developmental events continue to be collected. An additional season's worth of data are needed before reliable degree-day models can be developed and correlations between plant and arthropod phenology can be evaluated. Work on characterizing attributes of viburnums responsible for resistance to viburnum leaf beetle is proceeding smoothly. We have been able to clearly assign many viburnum species to susceptibility classes after quantifying feeding and oviposition damage in Highland Park in Rochester, NY, where a large number of viburnum species are present in close proximity and beetle populations have been high. Preliminary chemical analyses with a subset of viburnums differing with respect to susceptibility to viburnum leaf beetle have revealed that resistant viburnums possess at least compound
that is not possessed by susceptible viburnums. We will be screening a larger population of viburnums to see if this pattern holds, and if so, we will attempt to isolate this compound and determine its activity in isolation. If active, we will attempt to identify the compound.
Impacts
The results of these studies will enable landscape and nursery managers able to more precisely time control methods for major pests of landscape trees and shrubs. If significantly better predictors of arthropod emergence can be generated, it will increase the likelihood of adoption of growing degree-days or plant phenological indicators as aids to pest management, resulting in reduced use of pesticides. Knowing which traits in resistant viburnums confer resistance to viburnum leaf beetle could be useful in breeding efforts to produce and maintain viburnums with less insecticide use.
Publications
- McNiel, R.E., Weston, P.A. and Eshenaur, B.C. 2000. Viburnum beetle: A serious threat to the landscape. Proceedings of the Southern Nursery Association 45: 143-145.
|
|