Progress 07/01/06 to 06/30/10
Outputs
OUTPUTS: When this project started, methoprene was the only juvenile hormone (JH) analog commercially available, but it was phytotoxic, not practical for field use. However, we showed the potential of JH analogs against the codling moth, Cydia pomonella (Brown and Brown, 1982; Brown, 1985), and eventually both fenoxycarb and pyripoxyfen were registered for use in orchards. Our interests moved toward Lepidoptera specific ecdysteroid agonists, and we proposed a triad approach to orchard pest management (Brown, 1994). Our laboratory data (Brown, 1991; Brown and Reed-Larsen, 1991) showed the safety of tebufenozide toward beneficial parasitoid populations. We were interested in the potential of non-commercial sources of IGR too. We investigated how parasitoids regulated host development (Brown et al. 1988) and reported host castration (Reed-Larsen and Brown, 1990; Jones et al., 1990). This lead to book chapter that summarized a decade of research (Brown and Reed, 1997). We were attracted to botanical sources of IGR too. Our first effort concentrated on Artemesia (Suomi et al., 1986) and continues today (Pszczolkowski et al., 2009) through our collaboration with Dr. Maciej Pszczolkowski (currently an Assistant Professor, Missouri State University, but a Post-doctorate in our laboratory 1999 to 2004). Altogether 63 scientific publications were published between 1978-2009. PARTICIPANTS: Tree Fruit researchers at: WSU-Wenatchee, Missouri State University; University of Chile, Santiago Chile TARGET AUDIENCES: University and USDA tree fruit researchers and extension agents. PROJECT MODIFICATIONS: Work on this project is complete and terminated on June 2010.
Impacts
Overall this project was timely, when initiated orchards relied upon broad spectrum organophosphate insecticides, now those chemicals are no longer used or being phased out, and strategies that influence pest mating, feeding behavior, and chemicals with unique modes of action are being used. Insect Growth Regulators, especially pyripoxyfen (JH analog), methoxyfenozide (Ecdysteroid agonists), and novaluron (inhibitor of chitin deposition) have been useful during this transition toward safe chemical control of orchard pests.
Publications
- Durben, et al., 2010. Artemisia annua extracts and artemisinin but not 1,8 - cineole prevent apple feeding by codling moth neonates. submitted to J. Applied Entomology.
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Progress 01/01/09 to 12/31/09
Outputs
OUTPUTS: We are preparing a termination report for WPN00405 this year. Our efforts have moved toward a new Agricultural Research Service (ARS) project WPN00730. PARTICIPANTS: Tree fruit researchers at Washington State University, Wenatchee, Washington; Missouri State University at Mountain Grove, Missouri; and University of Chile, Santiago, Chile. TARGET AUDIENCES: University and USDA tree fruit researchers and extension agents. PROJECT MODIFICATIONS: Planning on terminating project 30 June 2010.
Impacts
In our termination report we will list 75 publications published describing the research conducted under this project over thirty years.
Publications
- No publications reported this period
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Progress 01/01/08 to 12/31/08
Outputs
OUTPUTS: We executed three Experimental Use Permits (EUP) testing the efficacy of Rynaxypyr, Clothianidin, and Emamectin-benzoate against the Cottonwood Leaf Beetle, Ten Lined June Beetle, and Poplar-and-Willow Borer, respectively. We documented that the parasitoid identified as Eulophus orgyiae attacks both Gluphisia septentrionis and Orthosia hibisci, and is found throughout the poplar plantations. We filed a patent application regarding a Modified Attract-and-Kill Device that should be as effective as a uniform bucket trap, but cost 90% less. PARTICIPANTS: R. A. Rodstrom, graduate student TARGET AUDIENCES: Forest industry, commercial poplar growers, scientists/researchers. We presented our annual progress report to GreenWood Resources, Portland OR, the largest grower of hybrid poplars in the Pacific Northwest. We published a scientific research article in the Journal of Economic Entomology. We gave seven oral and poster presentations to regional (Wiley Expo), national (Ecological Society of America), and international (Short Rotation Biofuels Conference). PROJECT MODIFICATIONS: We have funding to support another graduate student on this research program.
Impacts
As a result of our research, all commercial poplar growers are using Checkmate WPCM-F to control the western poplar clearwing moth. Of the 16 insecticides registered for use on hybrid poplars in Washington State, eight cannot be used in poplar grown under the Forest Stewardship Council guidelines, and we have conducted research leading to the registration of the other eight insecticides. In addition to these current eight, we are researching four more insecticides for possible registration in 2009.
Publications
- Pacific Northwest Poplars: A Resilient Arthropod Community and the Distribution of Insect-Caused Mortality in Cuttings. R.A. Rodstrom, J.J. Brown and J.R. Rodstrom. Short Rotation Crops International Collaboration. 2nd place, Minneapolis, MN. August 2008. http://www.nrs.fs.fed.us/pubs/gtr/gtr_nrs-p-31/49rodstrom-p-31.pdf
- Resilience or Rebound Terrestrial Arthropod Community Response to a Catastrophic Perturbance in Pacific Northwest Poplars. R.A. Rodstrom and J.J. Brown, Ecological Society of America Annual Meeting, Milwaukee, WI. August 2008. http://eco.confex.com/eco/2008/techprogram/S3734.htm
- Brown, J.J., and J. Eaton. 2008. Screening hybrid poplar clones for susceptibility to Cryptorhynchus lapathi (Coleoptera: Curculionidae). Journal of Economic Entomology. 101(1):199-205.
- Durden, K., J.J.Brown, and M.Pszczolkowski. 2008. Extracts of Ginkgo biloba or Artemisia species reduce feeding by neonates of codling moth, Cydia pomonella (Lepidoptera:Tortricidae), on apple in a laboratory bioassay. Journal of the Entomological Society of British Columbia. 105(105):1-6.
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Progress 01/01/07 to 12/31/07
Outputs
OUTPUTS: Among many other abiotic variations in an estuarine ecosystem, osmotic stress is an inescapable part of life. Organisms living in such environments must cope with changing osmotic conditions by either behavioral or physiological adaptations. Pollutants may increase the physiological stresses that an osmoregulating animal may encounter. We have developed a flow-through system that exposes test species to insecticides and continuously changing salinity conditions. This system has provided an insight into how susceptibility of a species to an insecticide can be affected by changing concentrations of salinity. Toxicity tests using this system were conducted with two arthropod species; the salt marsh mosquito Aedes taeniorhynchus (Wiedemann), and brine shrimp Artemia sp. that are found in saline habitats. Four insecticides aldicarb, dimethoate, imidacloprid, and tebufenozide, were studied. Both species were exposed for 48 h to a concentration of various insecticides that would
cause 50% of the population to die in hyperosmotic artificial sea water (ASW). The mortality rate for both species was more acute in increasing salinity (10 to 200% ASW) than in decreasing salinity (200 to 10% ASW) conditions. A. taeniorhynchus was more susceptible than Artemia when exposed to its hyperosmotic LC50 concentration of toxicant while experiencing a change in salinity, e.g. adjusting to a changing salinity decreased the LT50. Our results indicated a change in salinity, and more importantly the direction of change, altered the susceptibility of these organisms.
PARTICIPANTS: Andrew Rodstrom, Don Rice, Luke Maynard, Mike Berk, Donna Townsend, Donna Achoch, Earl Perkins, Jake Eaton, Cory Boswell, Brian Stanton, John Finley.
TARGET AUDIENCES: Poplar Growers of the Pacific Northwest.
Impacts
If ecdysone agonists are considered for mosquitocides, methoxyfenozide should be the most toxic but it needs to be tested against A. taeniorhynchus. Comparison of the literature would predict that A. taeniorhynchus should be quite susceptible to methoxyfenozide.
Publications
- No publications reported this period
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Progress 01/01/06 to 12/31/06
Outputs
Among many other abiotic variations in an estuarine ecosystem, osmotic stress is an inescapable part of life. Organisms living in such environments must cope with changing osmotic conditions by either behavioral or physiological adaptations. Pollutants may increase the physiological stresses that an osmoregulating animal encounters. We developed a flow-through system that exposes test species to insecticides and continuously changing salinity conditions. This system has provided an insight into how susceptibility of a species to an insecticide can be affected by changing concentrations of salinity. Toxicity tests using this system were conducted with two arthropod species; the salt marsh mosquito Aedes taeniorhynchus (Wiedemann), and brine shrimp Artemia sp. that are found in saline habitats. Four insecticides, aldicarb, dimethoate, imidacloprid, and tebufenozide, were studied. Both species were exposed for 48 h to concentrations of various insecticides that would
cause 50% of the population to die in hyperosmotic artificial sea water (ASW). The mortality rate for both species was more acute in increasing salinity (10 to 200% ASW) than in decreasing salinity (200 to 10% ASW) conditions. A. taeniorhynchus was more susceptible than Artemia when exposed to its hyperosmotic LC50 concentration of toxicant while experiencing a change in salinity, e.g. adjusting to a changing salinity decreased the LT50. Our results indicated a change in salinity, and more importantly the direction of change, altered the susceptibility of these organisms.
Impacts
If ecdysone agonists are considered for mosquitocides, methoxyfenozide should be the most toxic but it needs to be tested against A. taeniorhynchus. Comparison of the literature would predict that A. taeniorhynchus should be quite susceptible to methoxyfenozide.
Publications
- Song, M.Y. and Brown, J.J. 2006. The Influence of Fluctuating Salinity on Insecticide Tolerance of Two Euryhaline Arthropods. Journal of Economic Entomology. 99(6):745-751.
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Progress 01/01/05 to 12/31/05
Outputs
Neonate larvae of a lepidopteran, the codling moth (Cydia pomonella L.) search for their host fruit after hatch. The process of host searching is known to be activated by kairomones contained in host fruit volatiles, but the mechanism of actual selection and infestation of the fruit is unclear. We showed that lepidopteran neonates can utilize single experience learning in selection and infestation of host apple. We found that the process of host fruit selection may be modified by single experience learning, namely preference induction or averse conditioning. Both types of learning were acquired within 3 hours of training. Experience was retained for over 3 days in the case of averse conditioning. Preference induction, a form of learning specific to insects, is expected to produce rigid host preference lasting for days if not weeks, but in codling moth neonates this type of memory was retained only for 3 hours. We speculate that conjunction of preference induction with
short retention time and averse conditioning with long retention time provide an optimal adaptive strategy of host fruit selection for codling moth neonates. Feeding in codling moth caterpillars was induced by the general glutamate receptor activator monosodium glutamate (MSG) and by three different mGluR agonists known to specifically stimulate different classes of vertebrate metabotropic glutamate receptors, including: (1S,3R)-ACPD [(1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid], which stimulates group I mGluRs; (2R,4R)-APDC [(2R,4R)-4-aminopyrrolidine-2,4-dicarboxylate], which stimulates group II mGluRs; and L-AP4, which stimulates some group III mGluRs.
Impacts
Wilbur Ellis marketed a product called Devour as the direct result of our research on monosodium glutamate. Unfortunately this formulated MSG was a matrix material that masked the MSG from contact with the pest insect. We are working with Wilbur Ellis to develop a better formulation.
Publications
- Pszczolkowski M.A. and Brown, J.J. 2005. Single experience learning in host fruit selection by lepidopteran larvae. Physiology and Behavior, 86:168-175.
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Progress 01/01/04 to 12/31/04
Outputs
Neonate larvae of a lepidopteran, the codling moth (Cydia pomonella L.) search for their host fruit after hatch. The process of host searching is known to be activated by kairomones contained in host fruit volatiles, but the mechanism of actual selection and infestation of the fruit is unclear. We have shown that lepidopteran neonates can utilize single experience learning in selection and infestation of host apple. We found that the process of host fruit selection may be modified by single experience learning, namely preference induction or averse conditioning. Both types of learning were acquired within 3 hours of training. Experience was retained for over 3 days in the case of averse conditioning. Preference induction, a form of learning specific to insects, is expected to produce rigid host preference lasting for days if not weeks, but in codling moth neonates this type of memory was retained only for 3 hours. We speculate that conjunction of preference induction
with short retention time and averse conditioning with long retention time provide optimal adaptive strategy of host fruit selection for codling moth neonates.
Impacts
We have demonstrated a feeding behavioral response in codling moth neonates in response to monosodium glutamate and several pharmaceutical agonists of MSG to suggest a novel means of learning in insects. We had a patent disclosure throughout 2004 for the possible use of trans-ACBD a pharmaceutical MSG agonist in insect control strategies. Wilbur Ellis has marketed an adjuvant to insecticide treatment called Devour based on our research.
Publications
- No publications reported this period
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Progress 01/01/03 to 12/31/03
Outputs
We reported that monosodium glutamate is a feeding stimulant and an enhancer of pesticide toxicity against neonates of the codling moth. We showed that a monosodium glutamate alternative, trans-1-Aminocyclobutane-1,3-dicarboxylic acid, (trans-ACBD) alone and in the presence of spinosad, increases leaf tissue consumption by codling moth neonates. In contrast to monosodium glutamate, trans-ACBD maintains its feeding stimulatory properties in the field even after 20mm of simulated rain, and effectively increases spinosad efficacy both in laboratory and in the field experiments. Monosodium glutamate, a taste enhancer widely used in food industry, was tested in the laboratory to determine its phagostimulatory effects on larvae of Choristoneura rosaceana (Harris). Larvae fed apple leaves treated with 50-700 ug/l monosodium glutamate increased leaf tissue consumption by approximately 40%. The stimulatory effect of monosodium glutamate (at 675 ug/l concentration) was
maintained throughout 10 days of continuous exposure. Adding 675 ug/l monosodium glutamate to commercial formulation of Bacillus thuringiensis ssp. Kurstaki, DiPel" 2X DF, lowered LC50 from 450 to 150 ug/l (P<0.05, Lethal Ratio Significance Test), indicating good potential of monosodium glutamate for enhancement of Bacillus thuringiensis- based formulations.
Impacts
We have filed a patent disclosure statement with WSU's Intellectual Property Office and several companies have expressed interest.
Publications
- Horton, D. R., D. A. Broers, R. R. Lewis, D. Granatstein, R. S. Zack, T.R. Unruh, A.R. Moldenke, and J. J. Brown. 2003 "Effects of mowing frequency on densities of natural enemies in three Pacific Northwest pear orchards. Entomologia Experimentalis et Applicata 106: 135-145.
- Pszczolkowski M.A. and Brown J.J. 2003. Effects of sugars and non-nutritive sugar substitutes on consumption of apple leaves by neonates of codling moth. Phytoparasitica 31 (3); 283-291.
- Pszczolkowski M.A. and Brown J.J. 2003. Chilling affects allatal cell proliferation via antennae and protocerebral neurons in the cockroach Diploptera punctata. J. Insect Physiol.49: 123-129.
- Pszczolkowski, M., Zahand, A., Bushman, S.M., and Brown, J.J. 2003. Effects of calcium and glutamate receptor antagonists on leaf consumption by lepidopteran neonates. Pharmacology Biochemistry and Behavior 74: 389-394.
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Progress 01/01/02 to 12/31/02
Outputs
Generally, this project evaluated feeding stimulants to control neonates of lepidopteran orchard pests. The proposed strategy relied upon incorporating the feeding stimulants into pesticide formulations acting via alimentary tract, and reducing the amount of active ingredients without reducing overall efficacy of pest control strategy. In year 2001-2002 we concentrated on four specific objectives: 1. Improving rain-fastness of monosodium glutamate. 2. Large-scale field trial with pesticide formulations enhanced with MSG. 3. Initiation of studies on universal potential of MSG as feeding stimulator and enhancer of pesticides that have stomach activity. 4. Investigation of neonate's behavior on leaves treated with MSG. We have initiated our research toward incorporating the use of insect growth regulators in hybrid poplar plantings, by acquiring a Section 18 for the use of Dimilin, an IGR that prevents chitin deposition.
Impacts
We secured a Section 18 for the use of the Insect Growth Regulator (Dimilin) for use in poplar plantings against grasshoppers in both Washington and Oregon. This prevented the use of the much more toxic Lorsban (Chlorpyrifos) over 16,000 acres.
Publications
- Pszczolkowski M.A. and Brown J.J. 2001. Prospects of monosodium glutamate use for enhancement of pesticides toxicity against the codling moth. Phytoparasitca. 30: 243-252. 2001. (This publication was reported as being in press in our last CRIS report).
- Pszczolkowski, M., Matos, L., Zahand, A. and Brown, J. J. 2002. Effect of monosodium glutamate on apple leaf consumption by codling moth larvae. Entomologia Experimentalis et Applicata 103:91-98.
- Pszczolkowski, M.A., Matos, L.F., Brown, R., and Brown, J.J. 2002. Feeding and development of codling moth larvae on apple leaves. Ann. Entomol. Soc. Am. 95:603-607.
- Pszczolkowski, M., Zahand, A., Bushman, S.M., and Brown, J.J. 2002. Effects of calcium and glutamate receptor antagonists onleaf consumption by lepidopteran neonates. Pharmacology Biochemistry and Behavior DOI:10.1016/S0091-3057(02)01005-5.
- Chen, Y. Hansen, L., and Brown, J. J. 2002. Nesting sites of carpenter ant, Camponotus vicinus (Myar)(Hymenoptera: Formicidae) Environmental Entomol. 36 (6):1037-1042.
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Progress 01/01/01 to 12/31/01
Outputs
We have shown that neonates of the codling moth Cydia pomonella (L.) are capable of feeding and development on apple leaves, and identified a granulated sugar substitute, Sweet'n Low (1%, w/v), and monosodium glutamate (0.0025%, w/v) as substances that increase leaf feeding in codling moth neonates. In laboratory trials, addition of Sweet'n Low or monosodium glutamate to Success, a pesticide formulation containing Spinosad, increased its efficacy (by factor of 5.97x, and 2.94x, respectively) without increasing the amounts of toxic component. However, our semi-field experiments indicate that a more stable formulation of feeding stimulant/pesticide combination is needed to protect both from being washed from leaves by a rain. We also have preliminary data that characterize glutamate-dependent pharmacology of feeding in codling moth neonates, and improve field persistence of identified feeding stimulators. Our data suggest new strategy for rational pesticide reduction in
control of lepidopteran pests. Our formulation increased the amounts of pesticide ingested by stimulation of feeding, thereby showing prospects of decreasing the amounts of toxic ingredients needed in pesticide formulation without affecting its efficacy.
Impacts
Field trials using MSG in California on walnuts and in Washington State on apples are scheduled for 2002.
Publications
- No publications reported this period
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Progress 01/01/00 to 12/31/00
Outputs
Analyses of pitfall traps in Washington and Oregon apple orchards revealed that highly mobile invertebrates were strongly susceptible to applications of broad-spectrum, neural-active insecticides. When compared with orchard blocks managed without broad-spectrum insecticides, orchard blocks under conventionally managed regimes had significantly lower populations of ground beetles (Coleoptera: Carabidae), centipedes (Chilopoda), earwigs (Dermaptera: Forficulidae), harvestmen (Opiliones) and spiders (Aranae). The carabid species Pterostichus adstrictus and P. melanarius constituted 89% of all ground beetles collected over two growing seasons. Three times as many free hunting spiders were found in the no broad-spectrum blocks than in the conventional blocks. Less mobile invertebrates such as mites, slugs, and snails appeared to be less affected by the different management strategies. Ground beetles, spiders, harvestmen, earwigs, and centipedes are all probable predators
of lepidopteran and homopteran pests of apple.
Impacts
The potential of insect growth regulators is being realized in orchard ecosystems in the Pacific Northwest, however, some of these will benefit from adding feeding enhancing additives to form baits. This is especially true when targeting neonate larvae. We are investing some of these feeding enhancing materials this year.
Publications
- Epstein, D. L., R. S. Zack, J. F. Brunner, L. Gut, and J. J. Brown. 2000. Effects of Broad-Spectrum Insecticides on Epigeal Arthropod Biodiversity in Pacific Northwest Apple Orchards. Environmental Entomology, 29: 340-348.
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Progress 01/01/99 to 12/31/99
Outputs
Porapak Q volatile extracts of female Ascogaster quadridentata, an egg-larval endoparasitoid of codling moth, Cydia pomonella, bioassayed in Y-tube olfactometers attracted male, but not female, A. quadridentata. Coupled gas chromatographic-electroantennographic detection (GC-EAD) analysis of bioactive extracts revealed three compounds that elicit responses by male A. quadridentata antennae. GC-mass spectra (MS) indicated, and comparative analyses of authentic standards confirmed, that these compounds were (Z,Z)-9,12-octadecadienal, (Z)-9-hexadecenal, and 3,7,11-trimethyl-6E,10-dodecadienal. (Z,Z)-9,12-Octadecadienal alone attracted laboratory-reared male A. quadridentata in Y-tube olfactometer and field-cage bioassays, and attracted feral A. quadridnetata in a field experiment. This sex pheromone could be used to help detect populations of A. quadridentata, delineate their distributions, and determine potential sources of parasitoids for capture and release in
integrated programs for control of C. pomonella.
Impacts
(N/A)
Publications
- Delury, N.C., Gries, G., Gries, R., Judd, G. and Brown, J.J. 1999. Sex Pheromone of Ascogaster Quadridentata, a Parasitoid of Cydia Pomonella. J. of Chemical Ecology 25: (10) 2229-2245.
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Progress 01/01/98 to 12/31/98
Outputs
We confirmed the ability of genetically altered bacterium to survive within a leafroller midgut in the midst of competing microorganisms, thus it could serve as a suitable vehicle for biological control elements (McKillup et. al. 1997). Polyclonal antibodies demonstrated that a 27kD protein was released from chelonine parasitoid larva just prior to it's host molt. Production and release of ecdysteroids, as measured by RIA, was found to precede the peak occurrence of the 27 kD polypeptide (Reed and Brown, 1998). Aedes taeniorhynchus and Artemia sp. were exposed to four insecticides under isomotic and hyperosmotic conditions. Increased salinity causes greater mortality in euryhaline species exposed to pesticides, than was observed in isosmotic conditions (Song and Brown, 1998).
Impacts
(N/A)
Publications
- McKillip, J. L., C. L. Small, J. Brown, J. Brunner, and K. Spence. 1997. Sporogenous midgut bacteria of the leafroller, Pandemis pyrusana (Lepidoptera: Tortricidae). Environmental Entomology 26: 1475-1481.
- Reed, D. and J. J. Brown. 1998. Host/Parasitoid interactions: Critical timing of parasitoid-derived products. J. of Insect Physiology 44/9: 721-732.
- Song, M.Y. and J.J. Brown. 1998. Osmotic effects as a factor modifying insecticide toxicity on Aedes and Artemia. Ecotoxicology and Environmental Safety 41: 195-202.
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Progress 01/01/97 to 12/31/97
Outputs
The tolerance of four aquatic organisms to four chemicals (aldicarb, dimethoate, imidacloprid, and tebufenozide) was determined using 48-h acute toxicity tests at 27C. Our results suggest that both tebufenozide and imidacloprid would be selective insecticides that can be used with reasonable environmental safety toward nontarget aquatic crustaceans. There was a greater correlation of susceptibility to test chemicals within taxonomically close organisms than between organisms that share habitats.
Impacts
(N/A)
Publications
- Song, M. Y., J. D. Stark and J.J. Brown. 1997. Comparative toxicity of four insecticides, including imidacloprid and tebufenozide, to four aquatic arthropods. Environmental Toxicology and Chemistry. 16:
- Brown, J. J. and D. A. Reed. 1997. Host embryonic and larval castration as a strategy for the individual castrator and the species. Chapter 8 pp. 156-178; In: Parasites and Pathogens: .. Ed.
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Progress 01/01/96 to 12/30/96
Outputs
The ecdysone agonist, tebufenozide, appears to be a lepidopteran-specific insectgrowth regulator (IGR) that has no effect on ectoparasitic, Hymenoptera and only effects endoparasitic Hymenoptera indirectly through its affect on the host's physiology in laboratory tests. Hyssopus pallidus (Eulophidae) adults readily stung and oviposited on codling moth hosts that had slipped their head capsules forward after being fed an artificial diet containing up to 40 ppm (24 x LC50) tebufenozide, and their ectoparasitic progeny pupated. These eulophids were reared for 5 generations exclusively on hosts that were fed a high concentration of tebufenozide.
Impacts
(N/A)
Publications
- Brown, J. J. 1996. The compatibility of tebufenozide with a laboratory lepidopteran host/hymenopteran parasitoid population. Biological Control 6: 96-104.
- Gut, L. J., J. F. Brunner, Glenn Thayer and John Brown. 1996. SARE Project: production of apples without the input of broad-spectrum insecticides. Proc. Wash. State Hort. Assoc. 91: 239-241.
- Mee Young Song. 1996. Comparative toxicity of four insecticides, including imidacloprid and tebufenozide, to four aquatic arthropods and the influence of salinity on ..... Ph.D Dissertation under Dr. Brown supervision.
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Progress 01/01/95 to 12/30/95
Outputs
To elucidate the mode of action of ecdysteroids on the regulation of spermatogenesis, we treated isolated abdomens of diapausing codling moth larvae with the non-ecdysteroidal ecdysone-agonist Mimic (tebufenozide). Under similar conditions Mimic-treated abdomens renewed spermatogenesis, while corresponding untreated abdomens did not. Apparently, Mimic induces spermatogenesis reinitiation by attaching to, and saturating, a specific number of receptors causing an all or none type of response. Under laboratory conditions codling moth larvae parasitized late in their embryonic stage contained both testes and an endoparasitoid larva, this allowed synchronous observations of both parasitoid larval development and spermatogenesis. Other host eggs, after delayed exposure to parasitoid attack, were chilled which resulted in pseudoparasitized hosts containing testes. This condition allowed us to observe spermatogenesis in fourth stadium codling moth without the parasitoid larva
consuming the host. The timetable of spermatogenesis in pseudoparasitized individuals corresponded to that observed in late-parasitized larvae, but in addition to numerous eupyrene spermatids with elongating nuclei, apyrene metaphases and apyrene spermatids were observed.
Impacts
(N/A)
Publications
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Progress 01/01/94 to 12/30/94
Outputs
Host/Parasitoid Interactions: Dominant low molecular weight peptides (23-27 kD) were released by two chelonine parasitoids, Chelonus sp. near curvimaculatus and Ascogaster quadridentata in a stage-specific manner. The dominant peptide of Chelonus had a molecular weight of 27 kD and the native protein had an approximate molecular weight of 390 kD. The 27 kD peptide was synthesized de novo and occurred primarily during the late second stadium after the tracheae had matured and when exposed to air the larvae floated or molted during in vitro incubation. The synthesis and in vitro release of the 27 kD peptide appears to follow an increase in ecdysteroid release by the parasitoid. Application of exogenous 20-hydroxyecdysone stimulated overall protein release but its specific effect on the 27 kD peptide is undetermined. The site of synthesis and release of the 27 kD peptide appears to be the anal vesicle. Antibodies produced against the 27 kD peptide did not cross-react with
low molecular weight peptides present in larvae of Ascogaster nor peptides in host hemolymph or other host tissues. Also antibodies directed against the previously described 185 kD protein of Chelonus were not cross-reactive with the 27 kD peptide. Likewise the anti-27 kD peptide antibodies did not cross-react with the 185 kD protein.
Impacts
(N/A)
Publications
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Progress 01/01/93 to 12/30/93
Outputs
Ecdysone-agonist: The oral LC50 of tebufenozide in the diet for codling moth was0.02478 ppm. Ectoparasitoids can utilize host larvae exposed to tebufenozide without influencing their own development even though they do consume 14C-tebufenozide in its parent form from the host. The behavior of an endoparasitoid larva, within a host that has initiated apolysis in response to tebufenozide, remains unchanged. However if host apolysis occurs the endoparasitoid larva eventually dies as the results of host tissue decomposition. Ectoparasitic Hyssopus sp. (Eulophidae) can be reared for 5 successive generations on hosts that have apolysed in response to tebufenozide, however, Hyssopus population growth on tebufenozide fed hosts does not match the number that can be reared on control hosts. Oviposition Stimulants: Chelonus sp. near curvimaculatus females readily investigated and actively oviposited into artificial eggs constructed with various amino acids or insect culture media
sandwiched between Parafilm sheets. Among 11 amino acids tested, the positively charged arginine, histidine and lysine evoked intense ovipositional activity from Chelonus adults. Nonpolar methionine was slightly effective. More parasitoid eggs were oviposited into artificial eggs containing host (Trichoplusia ni) larval hemolymph than amino acids or artificial insect culture media tested. Dilution of host hemolymph with distilled water (1:15) significantly (P<0.05) reduced ovipositional activity. (Graduate Students = 2).
Impacts
(N/A)
Publications
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Progress 01/01/92 to 12/30/92
Outputs
Host Castration: Ascogaster reticulatus Watanabe castrates its host Adoxophyes sp. (Lepidoptera: Tortricidae). No gonads, male or female, develop in larvae that were stung as 0-day-old eggs. The parasitoid's effect on host development is time dependent. Delayed exposure of Adoxophyes sp. eggs to parasitoid attack increased the incidence of pseudoparasitism & abnormal gonads, & decreased the number of successfully eclosing A. reticulatus adults. Pseudoparasitized host/parasitoid interactions are made between A reticulatus and A quadridentata & their respective hosts, Adoxophyes sp. & Cydia pomonella L. Each parasitoid's development beyond the first stadium may depend on when its respective host commits to diapause. Parasitoid Production of Immunoreactive Ecdysteroids: Ascogaster reticulatus larvae removed from their host Adoxophyes sp. and held in vitro released immunoreactive ecdysteroids into Grace's medium. Initially 20-hydroxyecdysone & an unidentified polar
ecdysteroid were released, but ecdysone was also present after 24 h incubation. Regardless of age of host or size of parasitoid larva, maximum release of immunoreactive ecdysteroids occurred when a parasitoid larva developed opaque, fat body spots. We discuss the possibility of direct manipulation of host hemolymph ecdysteroid titer & subsequent apolysis of host integument, all initiated by release of ecdysteroids by parasitoid larva. Disclosure of Patents/Inventions DOMESTIC WATER TESTER, Patent #5,148,701, awarded 22 September 1992.
Impacts
(N/A)
Publications
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Progress 01/01/91 to 12/30/91
Outputs
Behavioral Cues: Emphasis was given to the influence that the host plant & surface lipids of the host plant have on insect herbivores & the predators & parasitoids of these herbivores. The cuticular lipids of species which interact on multiple trophic levels were compared. Similarities were found between hydrocarbons of herbivorous insects, their host plants, & their predators or parasitoids. JH III & Artemia: a) Ion transport enzyme (Na/K-ATPase) activity in stage III larvae of brine shrimp, Artemia, remained elevated throughout the stadium when populations were exposed to methoprene in artificial seawater. b) Infusion of methoprene, juvenile hormone, or methyl farnesoate caused increased Na/K-ATPase activity. Parasitoid in vitro production of ecdysteroids: Hemolymph concentrations of immunoreactive ecdysteroids were estimated by radioimmunoassay in healthy & parasitized larvae. There was a significantly (P < 0.001) higher concentration of ecdysteroids in hemolymph of
hosts with second stadium parasitoids than in hosts with first stadium parasitoids. Maximum host hemolymph titers of ecdysteroids occurred just prior to parasitoid eclosion, similar to the hormonal milieu found in healthy prepupae. Parasitized larvae exhibited prepupal behavior & morphology at the time of parasitoid egression from the host. Parasitoids excised from hosts & held in vitro released immunoreactive ecdysteroids into Grace's medium.
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Progress 01/01/90 to 12/30/90
Outputs
A. Embryonic Castration: Codling moth larvae parasitized by Ascogaster quadridentata are commonly devoid of any internal reproductive organs and exhibi precocious behavior. It was found that castration could be avoided if host exposure to the parasitoid was delayed until "late" in host embryogenesis. To be effective, the agent causing castration had to be introduced prior to 64 h of host embryonic development. If parasitized after 64 h, the diminutive host testes underwent a normal maturation sequence. Pseudoparasitized host pupae hav external sex characteristics, but no internal sex tissues, indicating a predilection of the castrating agent for mesodermal rather than ectodermal tissue. Host castration was not required for successful parasitoid emergence. The agent causing the castration and its mechanism are unknown. This is the first evidence of host castration occurring during embryogenesis. B. Calibration: A common laboratory color (ninhydrin) reaction to quantify
the amount of amino acids in solution can be used to calibrate research microsprayer to deposit a desired quantity of active ingredient onto a surface. Calibration can be achieved without visible residue on equipment, operators or targets. A modification of the technique can be used to measure canopy penetration.
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Progress 01/01/89 to 12/30/89
Outputs
Cuticular hydrocarbons: Cuticular hydrocarbon compositions were determined for: fruit and seed coat of apple; larvae and adults of codling moth; male and female adult Ascogaster quadridentata and Perilampus fulvicornis (Hymenoptera). The major cuticular hydrocarbons of codling moth larvae were identical to those extracted from the cuticle of the fruit and seed coat of its host, apple, although the larvae were reared on artificial diet shown to have a very different hydrocarbon content. The cuticular hydrocarbon composition of A. quadridentata was similar to that of the adult of its host, codling moth. Pentacosene, a major component of the cuticular hydrocarbons of female P. fulvicornis was the dominant component in the surface lipids of its host, A. quadridentata. Juvenile hormone effect on Artemia: Molting in stage III of the brine shrimp, Artemia, is interrupted, or even accelerated, when populations are exposed to various concentrations of juvenile hormone, methyl
farnesoate, or methoprene in artificial sea-water. The effects are believed to be salt-dependent, because exposure to these compounds in sea-water that is isotonic to hemolymph had no effect. This suggests that the juvenoids may target the ion transporting epithelia.
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Progress 01/01/88 to 12/30/88
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Data from my 1987 invited address in Poland has now been published. I presenteda second invited paper at the International Congress of Entomology in July 1988. Those data will be published early in 1989. These publications explain how the dormancy of both the host and parasitoid is due to a failure of the host's endocrine system. Data we presented in Louisville's National ESA meetings redefines the morphology of first stadium Braconid larvae. Researchers have for 50 years been defining the head capsule of first stadium, by the position of the mandibles, rather that where the brain is located. Our histological studies have found several such misconceptions about endoparasitoid morphology. We also investigated the possibility of using CO(2) to selectively kill chalcid parasitoids of the leafcutting bee, Megachile rotundata. Rather than being fatal to the parasitoids, the CO(2) delayed the initial development of the parasitoid's, so that their phenology was no longer
synchronized with that of their hosts. Seven times more bees emerged from populations of alfalfa leafcutting bee cells exposed to 100% CO(2), for 72 hr at 4C, than from control populations exposed to only air. We will terminate our studies of the effects of CO(2) on chalcid parasitoids in 1989.
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Progress 01/01/87 to 12/30/87
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Our laboratory has concentrated on the Ascogaster quadridentata/Cydia pomonella,parasitoid/host system. We're interested in the neuroendocrine communications between the host and its endoparasitoid in relationship to dormancy of both animals. We've used dormancy to accumulate large numbers of host/parasitoid units for experiments requiring synchronized parasitoid development. Dormancy of both host and parasitoid is due to a failure of the host's endocrine system. Upon transfer of the host from dormancy-maintining to dormancy-terminating conditions, a hemolymph borne host cephalic substance is released. Parasitoid larvae respond to the cephalic factor, and/or secondary host substances released in response to the cephalic factor, by increasing their body size and molting to their second stadium. Our current knknowledge of the Ascogaster/Cydia system should lend itself to an investigation of possible growth regulators involved in this parasitoid/host system.
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Progress 01/01/86 to 12/30/86
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We continue to investigate how the braconid parasitoid Ascogaster quadridentata prevents pupation of its codling moth host. The parasitoid overwinters as a neonate within its dormant host. This behavior allows us to stockpile a large number of parasitized codling moth larvae for subsequent research. Upon transfer of dormant hosts to dormancy terminating conditions (DTC), the parasitoids initiate rapid post neonate development (PND) and control the destiny of hosts. The parasitoid molts into the second stadium within 72 h and emerges as an ectoparasitic third instar after one week. Host dormancy synchronizes the development of both host and parasitoid so that as dormancy is terminated the endocrine interaction between the two can be studied. Upon transfer of the host to DTC a 'head factor' is released within 36 h. The 'head factor' is currently being characterized. An injection of 20-hydroxyecdysone initiates PND of the parasitoid in head ligated host but
sustained endoparasitoid development requires an unimpeded flow of hemolymph to the host's brain. Methoprene an analog of juvenile hormone (JH) effects the parasitoid's PND in dose dependent manner. A1 ng topical application of methoprene to the host causes a significant (P>0.05) increase in parasitoid PND over parasitoid development in acetone treated control hosts. Methoprene's influence on parasitoid PND only occurs in non-head ligated hosts.
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Progress 01/01/85 to 12/30/85
Outputs
Several herbicides were examined for insect growth regulatory activity. Ingestion of thiobencarb and triallate quantitatively suppressed the biosynthesis and/or deposition of long chain cuticular hydrocarbons in Trichoplusia ni larvae. Oral LC(50's) of thiobencarb and triallate were 298 and 570 ppm respectively. Pupae developing from larvae fed a diet containing 700 ppm triallate had larval prolegs on the ventral surface of their abdomen, suggesting an imbalance of juvenile hormone concentration. Endothall was toxic to T. ni larvae (LC(50)476) but its mode of action did not include inhibition of C Leucine incorporation into protein. Glyphosate had no developmental effect on T. ni larval development. I determined Q(10) activity information on JH specific esterases in non-diapausing and diapausing codling moth larvae. This information will be used to develop a model for the influence of temperature on JH metabolism. My laboratory has established a population of
Ascogaster quadridentata and we have initiated an investigation into how this parasite prohibits the pupation of codling moth larvae.
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Progress 01/01/84 to 12/30/84
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We're continuing our research (1981 CRIS Report) into the relationship of juvenile hormone (JH) regulation of larval diapause in the codling moth. Our goal is to characterize the influence of temperature upon JH degradative enzymes and JH carrier proteins. During 1984, we re-established a diapausing colony of codling moths from a local population and acquired a JH photoaffinity analogy, (10,11 epoxyfarnesyl diazoacetate) EFDA. This researcher was on professional leave during much of this time period and had no base research support to carry on the project in his absence.
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Progress 01/01/83 to 12/30/83
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Feeding deterrency demonstrated by the use of plant extracts: Chloroform and methanol extracts from 25 plant species were presented in a bioassay to neonatal codling moth larvae. Chloroform extracts of tansy, Tanacetum vulgare (L.); rabbitbrush, Chrysothamnus nauseous (Pallas); and wormwood, Artemesia absinthium (L.) showed significant antifeedant activity. Terpenes present in these extracts very likely masked the attractancy of apple to the larvae or, repelled the insects. The plant extracts neriifolin, from false white teak, Trewia nudiflora (L.); and trewiasine, from Mexican yellow oleander, Thevetia thevetioides (HBK) K. Schumann resulted in high mortality of neonates contacting these materials, suggesting potential as insecticides.
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Progress 01/01/82 to 12/30/82
Outputs
Diapause physiology with special regard to juvenile hormone involvement: Hemolymph from diapausing codling moth larvae was shown to contain a dominant soluble protein, which was of minor significance in the hemolymph of nondiapausing larvae. This hemolymph protein was accumulated during the ultimate instar and its concentration remained constant throughout diapause development. The selective accumulation of this diapause protein is either under the control of photoperiod and/or juvenile hormone (JH), since treatment with a JH mimic can result in accumulation of the protein. The exact role of the diapause protein is unknown, but it disappears from the hemolymph during diapause termination, suggesting that it may be involved in pupal or adult development. Short-Day (SD) photoperiods are the primary stimulus for diapause induction. Starvation, JH mimic treatment, or exposure to cooler temperatures can extend the length of the ultimate instar, add SD exposures, and
result in reprogramming of larvae initially programmed to pupate. Juvenile hormone esterase (JHE) activity in the hemolymph of larvae destined to enter diapause exceeded levels found in blood of nondiapause larvae, suggesting that inactivated JHE is not responsible for higher levels of JH in the hemolymph of larvae destined to diapause.
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Progress 01/01/81 to 12/30/81
Outputs
Codling moth larvae reared through the penultimate instar under long-day conditions are committed to pupate, but reprogramming can occur if larvae are exposed to 20 or more days of short-day photoperiods. The ultimate instar can be prolonged to allow reprogramming by: exposure to methoprene, low temperatures, or starvation. Mimics of juvenile hormone (JH) induced diapause by prolonging the ultimate instar which allowed reprogramming, rather than a direct result of their mimicry. We have isolated, identified and partially characterized: a JH specific esterase (JHE); a JH specific binding protein, and a non-specific lipoprotein carrier of JH. Hemolymph from diapause programmed codling moth larvae had more JHE activity than hemolymph of non-diapause larvae. Isotype experiments suggest that amino acids ingested late in the ultimate instar of the codling moth are preferentially incorporated into adult tissue, including reproductive organs and eggs. An investigation of
metabolic changes that occur during diapause termination in the codling moth suggested 3 stages: larvae loss up to 12% of their live body weight and the ratio of hemolymph volume/live body weight decreased significantly; fat body protein increased 2-fold and volume of testes increased 60% as larvae loss an additional 8% of their live body weight; and after larvae had loss 20% or more of their live body weight, larvae are within 24 hr of apolysis to pharate-pupae. The final-stage was a period of metabolic equilibrium.
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Progress 01/01/80 to 12/30/80
Outputs
The insect growth regulator methoprene reduced the fecundity and fertility of female codling moths after exposure to a sublethal dose (0.0l Mug) of the juvenile hormone mimic (JHM) during the last larval instar. Exposure to higher dosages (0.1 or 1.0 Mug methoprene) caused significant pupal mortality in the exposed generation. Vitellogenesis was investigated in the codling moth. Vitellogenesis was shown to be initiated concurrently with wing coloration and patterning in 7 to 8 day old pupae. Vitellogenin (VG) and vitellin (V) proteins were immunologically and electrophoretically identical. The V was characterized as a lipoglycoprotein (365,000 MW) high in aspartate/asparagine, glutamate/glutamine and serine. We are characterizing the changes in metabolic constituents associated with diapause termination in the codling moth. The effort has concentrated on changes in hemolymph, fat body and testicular proteins. Physiological effects of volcanic ash upon insects were
studied. Generally, death was a result of cuticular abrasion and subsequent dehydration. Direct absorption of body fluid through an undamaged integument was minimal. Inhalation and/or ingestion of ash did not cause death in insects studied.
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Progress 01/01/79 to 12/30/79
Outputs
Colorado potato beetle populations fed the foilage of solanum sarrachoides have been shown to undergo slower larval development and sexual maturation than beetles fed S. tuberosum. This study has revealed a new record fecundity for Leptinotarsa decemlineata exceeding all previous reports. Polyacrylamide gel electrophoresis was used to characterize the normal protein pattern of the fat body, hemolymph and ovaries of female codling moths during metamorphosis. Antibodies to the yolk proteins were made so that these compounds could be immulogically identified. Concurrently, a time and dosage study was used to determine the effect of juvenile hormone mimics (JHM) upon codling moth fecundity. Exposure to 0.1 Mug/larva of JHM, 48 hrs after the last larval-larval molt, brought about a 75% reduction in adult females, and none of the surviving adults produced greater than 50 eggs. Current research is linking the insect hormone mimic, protein metabolism, and reduced
fecundity. The ability of various JHM to induce a "diapause-like" condition in larvae reared in diapause-averting conditions has been studied. Methoprene and ZR-1662 are both effective, and lower temperatures increase the number of "diapause-like" responses to these JHM.
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Progress 02/01/78 to 12/30/78
Outputs
A codling moth culture was established on an artificial diet from pupae providedby the USDA Laboratory at Yakima, WA. The culture has been maintained in 3 separate incubators of various photoperiods to provide both diapausing and non-diapausing larvae for various experiments. Developmental information has been obtained for this codling moth population. Five juvenile hormone mimics (JHM) were tested for their ability to induce a diapause-like state of development in the codling moth. The concentration of hemolymph protein was determined for the last larval instar of the male codling moth throughout nondiapause and diapause development. The hemolymph and fat body soluble proteins of both diapausing and nondiapausing male larvae were compared using acrylamide disc-gel electrophoresis. A biochemical explanation was sought for unpublished observations suggesting that diapausing Colorado Potato beetles (CPB) and CPB reared on an alternate host plant, produced fewer
offspring than nondiapausing CPB reared on potato foliage. Further studies are planned to more carefully examine experiments that have indicated a reluctance of CPB to feed upon foliage dipped in an aqueous homogenate of other potato feeding insects. Investigating the fecundity of female codling moths subsequent to their exposure to an exogenous source of JHM. The objective is to characterize, subtle changes in a female specific protein, which results in the partial or complete sterilization of the exposed insects.
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