Progress 03/26/10 to 04/20/11
Outputs
Progress Report Objectives (from AD-416) Expeditiously identify chemical attractants (e.g., pheromones and plant volatiles) for agriculturally important insect species (either pests or biocontrol agents for weed or insect pests) for which such knowledge is lacking or incomplete, determine the biological and environmental parameters for natural emission of the compounds, and synthesize or otherwise obtain them in quantities sufficient for field use. Characterize the behavioral responses toward the identified compounds under field conditions, with special consideration to the development of practical management tools. Approach (from AD-416) The overall goals of this proposed research are to identify compounds that are attractive to pest insects and beneficial insects and to develop these semiochemicals into practical applications such as monitoring tools and pest control strategies. The project focuses on insect species for which such information is lacking or incomplete. The target species belong to a diverse group of insects: The emerald ash borer (EAB), Agrilus planipennis, is a severe invasive buprestid pest of ash trees in North America. Host volatiles and essential oils contain several biologically active compounds useful for monitoring EAB. Purification and synthetic methods will be developed to obtain these target compounds in quantities necessary for field experiments. Three exotic parasitoids, Spathius agrili, Oobius agrili, and Tetrastichus planipennis have been released as possible EAB biocontrol agents. Semiochemicals involved in the parasitoid-host-tree complex will be identified focusing first on pheromones as attractants in monitoring the survival and establishment of newly released parasitoid populations. Diorhabda spp. are introduced biocontrol beetles for the invasive weedy tree, saltcedar (Tamarix spp.). Pheromone components for Diorhabda spp. are known, but the precise blend ratios for optimal attractiveness are still incomplete and will be further investigated. The lesser mealworm beetle (LMW), Alphitobius diaperinus is a global insect pest of commercially raised poultry. The pheromone blend of the LMW has recently been identified and can be synergized with poultry manure volatiles. However, knowledge on the correct blend composition is lacking. Optimized blends will be field- evaluated in order to develop a LMW control strategy. Users of the research results would be grower groups, regulatory agencies, land management agencies, businesses dealing with insect attractants, and other scientists. The emerald ash borer (EAB) is an invasive beetle pest from Asia causing widespread mortality of ash trees in the US and Canada. National surveys, performed by federal and state agencies, are to determine the presence of EAB in forests, woodlots, and urban areas. These surveys rely on traps baited with attractants that are placed in still healthy ash trees. The current attractants are based on compounds released by stressed ash trees. Since these attractants are not commercially available they will have to be synthesized. We have identified the absolute chemical structure of one of the major EAB host attractants. This result is important so that the correct chemical is made for the bulk synthesis of EAB host attractants. The saltcedar beetles are leaf beetles that have been introduced into the USA as biocontrol agents for saltcedar. These beetles, originally from Asia and Europe, have been released into riparian areas in the Western United States where saltcedar, an invasive weedy tree, has caused great ecological and economic damage. Earlier, we have identified a combination of male-produced pheromone and a host odor attractant based on saltcedar green leaf volatiles and these attractants have been used in monitoring the presence of newly released beetles. Beetle dispersal from these established populations can be easily followed by baited traps, especially in areas with no visual proof of any beetle presence. However, the exact pheromone components blend ratio and natural release rates for different saltcedar beetle species, from lab colonies and field populations, has not yet been investigated. We have measured the pheromone release rated from individual beetles for two species, synthesized the pheromone components, and formulated the pheromone into rubber stoppers. The pheromone release rate from these rubber stoppers mimics the release rate from the beetles and these rubber stoppers are a practical lure for the beetles in the field. Accomplishments 01 Determination of the absolute chemical structure of a host attractant fo EAB. The emerald ash borer (EAB) is a severe invasive beetle pest of as trees in North America. EAB is attracted to compounds emitted by stresse ash trees. We have identified the absolute chemical structure of one of the major EAB host attractants. This result is important so that the correct chemical is made during large-scale synthesis of EAB host attractants that are used in national EAB surveys. These surveys will he to pinpoint the presence of EAB populations and will further assist in t control of EAB such as the release of natural enemies at the correct locations.
Impacts
(N/A)
Publications
- Nichols, W.J., Cosse, A.A., Bartelt, R.A., King, B.H. 2010. Methyl 6- methylsalicylate: A female-produced pheromone component of the parasitoid wasp Spalangia endius (Hymenoptera: Pteromalidae). Journal of Chemical Ecology. 36(10):1140-1147.
- Bartelt, R.J., Zilkowski, B.W., Cosse, A.A., Schnupf, U., Momany, F.A., Vermillion, K. 2011. Male-specific sesquiterpenes from Phyllotreta flea beetles. Journal of Natural Products. 74(4):585-595.
- Khrimian, A., Cosse, A.A., Crook, D.J. 2011. Absolute configuration of 7- epi-sesquithujene. Journal of Natural Products. 74(6):1414-1420.
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Progress 10/01/09 to 09/30/10
Outputs
Progress Report Objectives (from AD-416) Expeditiously identify chemical attractants (e.g., pheromones and plant volatiles) for agriculturally important insect species (either pests or biocontrol agents for weed or insect pests) for which such knowledge is lacking or incomplete, determine the biological and environmental parameters for natural emission of the compounds, and synthesize or otherwise obtain them in quantities sufficient for field use. Characterize the behavioral responses toward the identified compounds under field conditions, with special consideration to the development of practical management tools. Approach (from AD-416) Seek pheromones and host-plant related attractants for selected insect species. Species studied will include, but not be limited to, Diorhabda elongata (a biocontrol agent of saltcedar), Galerucella calmariensis (a biocontrol agent of purple loosestrife), and various flea beetle species (including vegetable crop pests and also biocontrol agents of leafy spurge). Collect volatiles from male and female insects and from host plants and analyze these by gas chromatography, mass spectrometry, and electrophysiology (�electroantennograms�). Those compounds that are emitted by just one sex and that are detected with great sensitivity by the insect antennae are likely to be pheromone components. Similarly, host plant compounds with high antennal sensitivity are potential attractants. Identify the structures of these key compounds using mass spectrometry, nuclear magnetic resonance spectroscopy, chemical tests, and other appropriate methods. Synthesize the compounds using the methods of organic chemistry or otherwise obtain them in bulk from botanical or other sources. Use techniques such as �sticky traps� or other trapping methods to evaluate the attractiveness of synthetic compounds under field conditions, relative to controls and also to live insects. Characterize the behavior toward the attractants under laboratory conditions, if possible. Develop the newly identified attractants as practical insect management tools, for monitoring or manipulating populations of the insects under consideration. For key pheromones, such as those of nitidulid beetles, develop new synthetic schemes suitable for commercial pheromone production. This research project is the continuation of 3620-22000-008-00D until the new project is established.
Impacts
(N/A)
Publications
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