Source: AGRICULTURAL RESEARCH SERVICE submitted to
BIOLOGICAL CONTROL OF EXOTIC AND INVASIVE PESTS
Sponsoring Institution
Agricultural Research Service/USDA
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0406896
Grant No.
(N/A)
Project No.
6204-22000-016-00D
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Apr 9, 2003
Project End Date
Jun 21, 2005
Grant Year
(N/A)
Project Director
GOOLSBY J
Recipient Organization
AGRICULTURAL RESEARCH SERVICE
(N/A)
WESLACO,TX 78596
Performing Department
(N/A)
Non Technical Summary
(N/A)
Animal Health Component
30%
Research Effort Categories
Basic
40%
Applied
30%
Developmental
30%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2150999113010%
2151131113010%
2151440113010%
2151451113010%
2151460113010%
2151461113010%
2151510113010%
2151710113010%
2151820113010%
2152300113010%
Goals / Objectives
1) Develop classical biological control approaches for arthropod pests food and fiber crops with emphasis on established pests. 2) Determine exotic arthropod crop pests that are potential threats to agriculture via entry through Mexico and Central America, and initiate onsite management programs in collaboration with foreign scientists. 3) Conduct and evaluate biological control-based management of aquatic and terrestrial weeds.
Project Methods
Exotic egg parasitoids will be collected from related sharpshooters that are pre-adapted to California's subclimate types and WILL successfully attack glassy-winged sharpshooter eggs. Imported parasitoids will be new species and indistinguishable from native parasitoids, but molecular-based diagnostics will be developed to distinguish them as well as identify possible species complexes among native parasitoids. Semiochemicals involved in communication between and among plants, sharpshooters and parasitoids, will be identified and manipulated to enhance biological control of the glassy-winged sharpshooter.

Progress 04/09/03 to 06/21/05

Outputs
1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter? Each year, new insect, mite, and weed pests enter the U.S. and add to the existing pest pressure on our food and fiber crops. Exotic and invasive insects and weeds cost the U.S. over $122 billion per year in crop losses and control costs. At a time when reduction in pesticide use is a national priority, the appearance of new pests challenges our ability to reduce pesticide use. The costs associated with trying to control these pests and the use of chemical pesticides makes agricultural products more costly and leaves behind potentially toxic residues. These issues are being resolved by this project through the development of new technologies that take advantage of the pests' own natural enemies to reduce damage in a sustainable manner. Naturally occurring predators, parasitoids, and diseases will be identified in their area of origin, then collected, imported, and evaluated for their ability to control the targeted pests. Recent techniques in molecular biology, biochemistry, and chemical ecology will be integrated with conventional classical biological control techniques to develop new technological advances in the field of biological control. Aquatic weeds have invaded natural and man-made waterways around the world, resulting in destruction of local aquatic ecosystems as well as causing serious social and economic consequences; costs associated with aquatic weed control and lost revenues run into the millions for single U.S. states each year. Chemical control of weeds in many areas is prohibited by regulatory agencies. Invasive terrestrial weeds in crops and adjacent areas threaten crop production and scarce natural resources. This project contributes to the Crop Protection and Quarantine National Program (NP 304), and specifically addresses the Biology of Pests and Natural Enemies; Plant, Pest, and Natural Enemy Interactions and Ecology; Pest Control Technologies; and Biological Control of Weeds research components by providing new information regarding ecological interactions between exotic and invasive plant pests and crop production systems, and new technologies for more effective and environmentally friendly pest control. Portions of the research contribute to the Agroengineering, Agrochemical, and Related Technology component of the Crop Production National Program (NP 305) by supporting the goals and research needs of the glassy-winged sharpshooter (GWSS) program through development of improved glassy-winged sharpshooter monitoring and control technology. This work also contributes to the Genetic Resource Management; Genomic Characterization and Genetic Improvement; and Genome Databases and Bioinformatics components of the ARS National Program on Plant, Microbial, and Insect Genetic Resources, Genomics, and Genetic Improvement (NP 301) by collecting and preserving geographic populations of the GWSS, its relatives and natural enemies, with the ultimate goal of developing more productive and adaptable natural enemies for GWSS control. Specific Cooperative Agreements are in place with Texas A&M University and the University of California, Riverside, to facilitate achievement of project objectives. Growers and consumers of crops affected by targeted pests will benefit from reduced pesticide use and the collateral problems associated with pollution. The nation's waterways will be cleaner and its water supply will be more available with aquatic weeds being effectively controlled by appropriate biological control organisms. 2. List the milestones (indicators of progress) from your Project Plan. Year 1 (FY 2003): 1. Collect exotic egg parasitoids of the glassy-winged sharpshooter in South America and ship to U.S. 2. Begin evaluation in quarantine. 3. Bioassay sharpshooter adults and parasitoids for behavior-modifying compounds. 4. Isolate and identify chemistry of bioactive compounds. 5. Develop molecular genetic markers for the GWSS by various PCR-based DNA fingerprinting methods. 6. Collect geographic populations of GWSS and extract DNA for genetic characterization studies (origin and geographic variation). 7. Complete studies of defense/stress via chemical changes in pigweed. 8. Bioassay beet armyworm on stressed/infected pigweed. 9. Initiate field study in cotton with pathogen-infected pigweed. 10.Develop molecular genetic markers for GWSS egg parasitoids (Gonatocerus species) for genetic studies. 11.Develop GWSS-specific molecular diagnostic markers to identify key predators. Year 2 (FY 2004): 1. Continue collection of exotic egg parasitoids of the glassy-winged sharpshooter in South America and ship to U.S. 2. Continue evaluations in quarantine. 3. Continue bioassays of sharpshooter adults and parasitoids for behavior- modifying compounds. 4. Continue to isolate and identify chemistry of bioactive compounds. 5. Seek commercial partners for development and practical use of behavior- modifying compounds. 6. Determine the best treatment that enhances biocontrol of waterhyacinth. 7. Complete first year of sampling waterhyacinth. 8. Apply for permits to import novel biocontrol agents for weeds. 9. Complete field studies on infected/noninfected pigweed in cotton. 10.Complete experiments with novel agents of waterhyacinth. 11.Complete development of molecular markers for the GWSS. 12.Compete geographic study of GWSS populations to determine origin and geographic/population structure/variation. 13.Start to genetically characterizing geographic populations of the GWSS predominant egg parasitoid, G. asheamdi to determine if cryptic species exists, geographic variation, and to identify geographic-specific markers. 14.Start genetically characterizing geographic populations of another GWSS egg parasitoid, G. morrilli to determine if cryptic species exist. 15.Start testing the various GWSS-specific diagnostic markers on various predators. Year 3 (FY 2005): 1. Continue evaluations of glassy-winged sharpshooter parasitoids from South America in quarantine. 2. Continue bioassays of sharpshooter adults and parasitoids for behavior- modifying compounds. 3. Continue to isolate and identify chemistry of bioactive compounds. 4. Complete field studies on infected/noninfected pigweed in cotton. 5. Complete experiments with novel agents of waterhyacinth. 6. Complete genetic studies of GWSS egg parasitoid, G. ashmeadi. 7. Complete genetic studies of GWSS egg parasitoid, G. morrilli. 8. Complete development of GWSS-specific diagnostic markers and testing on predators 3a List the milestones that were scheduled to be addressed in FY 2005. For each milestone, indicate the status: fully met, substantially met, or not met. If not met, why. 1. Continue evaluations of glassy-winged sharpshooter parasitoids from South America in quarantine. Milestone Substantially Met 2. Continue bioassays of sharpshooter adults and parasitoids for behavior- modifying compounds. Milestone Substantially Met 3. Continue to isolate and identify chemistry of bioactive compounds. Milestone Substantially Met 4. Complete field studies on infected/noninfected pigweed in cotton. Milestone Substantially Met 5. Complete experiments with novel agents of waterhyacinth. Milestone Not Met Progress slowed by resource limitation (human,fiscal,equipment, etc. 6. Complete genetic studies of GWSS egg parasitoid, G. ashmeadi. Milestone Substantially Met 7. Complete genetic studies of GWSS egg parasitoid, G. morrilli. Milestone Substantially Met 8. Complete development of GWSS-specific diagnostic markers and testing on predators. Milestone Substantially Met 3b List the milestones that you expect to address over the next 3 years (FY 2006, 2007, and 2008). What do you expect to accomplish, year by year, over the next 3 years under each milestone? This project expired in FY 2005 and has been replaced by a new project which has been approved through the OSQR process. Projected milestones are discussed in the annual report for the new project. 4a What was the single most significant accomplishment this past year? Molecular characterization of gut contents of GWSS predators. A new molecular technique to determine which predator insects feed on GWSS has been developed and implemented in field studies. Little is known about the predator insect complex that feed on eggs, nymphs, or adult GWSS, and direct visual field observations of predation are difficult to obtain and often inaccurate. A BIRU scientist in Weslaco, TX, in collaboration with ARS scientists in Phoenix, AZ, and the University of California in Berkeley, developed, for the first time, GWSS- specific molecular diagnostic markers to aid in identifying key predator species. The diagnostic markers [Sequence Characterized Amplified Region (SCAR) and mitochondrial COI and COI] are specific for GWSS and are able to identify GWSS remains at all life stages (eggs, nymphs, and adults) in predator gut contents. Preliminary field studies in the GWSS-impacted areas of California have successfully identified predators using the new markers, particularly the COI markers. These diagnostic markers for the GWSS will allow us to better understand the ecology of GWSS-predator interactions in the agroecosystem, and to develop integrated pest management programs that conserve the key predator species. 4b List other significant accomplishments, if any. Release of biological control agents of glassy-winged sharpshooter (GWSS) from Texas in California. Glassy-winged sharpshooter is a vector of Pierce's disease in California grapes. Four species of egg parasitoids from native range of GWSS in Texas (Gonatocerus morrilli, G. nr. morrilli, G. ashmeadi, and G. triguttatus) were collected; evaluated by the Beneficial Insects Research Unit, Weslaco, TX; and shipped to collaborators in California (CDFA) for mass rearing and release. One species G. triguttatus is now established and spreading beyond the release locations. Improving the impact of waterhyacinth weevils. Waterhyacinth is a serious aquatic weed in the southern U.S. from California to Florida, including the Rio Grande River Basin in Texas. Research conducted at Beneficial Insects Research Unit (Weslaco, TX) has demonstrated that the existing waterhyacinth weevils can carry a plant pathogenic fungus. Lab experiments showed that waterhyacinth weevils, which are important biological control agents of waterhyacinth, can be sprayed with spores of a plant pathogen fungus without any adverse effects and that the weevils can transmit the fungus to fungal culture medium. The technique could substantially improve the impact of the existing biological control agents of this noxious aquatic weed. Discovery of new glassy-winged sharpshooter (GWSS) parasitoid species using molecular methods. Glassy-winged sharpshooter is a vector of Pierce's disease in California grapes. Research conducted at Beneficial Insects Research Unit (Weslaco, TX) using molecular methods has shown that one of the primary GWSS egg parasitoids (Gonatocerus morrilli) is actually a complex of cryptic species. Diagnostic markers were developed and are being used to track the establishment of a unique pre-adapted population from the origin of GWSS in Texas. This technique was also used to distinguish and track geographic populations of G. ashmeadi from Texas and Louisiana that were recently released in California. This research will confirm whether parasitoids from the origin of the invasive pest are more effective biological control agents. 4c List any significant activities that support special target populations. The BIRU has close collaborative ties with the University of Texas Pan American (UTPA), Edinburg, TX, which has the largest enrollment of Hispanic students of any university in the U.S. The BIRU employs nine full-and part-time student technicians from UTPA, two of which are completing M.S. degrees based on research related to the objectives of this project. 4d Progress report. A new scientist with expertise in chemical ecology, Dr. Joe Patt, joined the unit in September 2004. Dr. Walker Jones, formerly the lead scientist on this CRIS, accepted a position as director of the ARS- European Biological Control Laboratory in December 2004. Dr. John Goolsby transferred to the BIRU from the Australian Biological Control Laboratory in January 2005 and is the Acting Research Leader. 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. A biological control program was initiated for the insect pest, glassy- winged sharpshooter (GWSS), which is native to Texas and invasive in California, where it vectors the lethal Pierce's disease of grapes. Molecular genetic tools were developed and used to determine the origin of GWSS in Texas, to detect cryptic species of the parasitoids, and determine the presence of GWSS in the gut contents of key predator insects. A suite of egg parasitoids were collected in Texas, reared, evaluated, and shipped to cooperators in California for mass rearing and release. Several of these species are now established and spreading from release sites in California. Exploration for additional natural enemies was conducted in Argentina using the 'new association' strategy and several new species from a related sharpshooter were discovered and are undergoing host range evaluation in U.S. quarantine facilities. Biological Control of GWSS: Four species of GWSS egg parasitoids from Texas (G. morrilli, G. nr. morrilli, G. ashmeadi, and G. triguttatus) were collected, evaluated, and shipped to collaborators in California (CDFA) for mass rearing and release. One species, G. triguttatus, is now established and spreading beyond the release locations. The Texas parasitoids come from the origin of the invasive California GWSS populations. These species have co-evolved with the target pest and therefore have highly specialized host-finding abilities which increases the potential for successful biological control. A second approach was taken to find additional natural enemies that attack proconine sharpshooters that are also climatically adapted to the Mediterranean climate where GWSS is a pest in California. This approach is called neoclassical biological control in which biological control agents come from host species that are closely related to the target pest. Following this strategy, exploration for biological control agents was conducted in the Mediterranean climatic regions of South America where proconine sharpshooters are common. Twelve species of egg parasitoids were collected, several of which were new to science. These species were imported to quarantine facilities in the U.S. for further evaluation. In summary, a suite of biological control agents were discovered from the native range of GWSS in Texas and from Mediterranean Argentina. Several of these agents have been released and/or established in California as part of a integrated pest management program to reduce population levels of GWSS and lower the incidence and spread of Pierce's disease in the agroecosystem. Molecular Genetics: The first goal of this project was the development of molecular genetic markers for the GWSS. Development of DNA markers with four DNA fingerprinting methods was the single most significant accomplishment during FY 2003. These markers were important because not only were they able to distinguish three Homalodisca X. fastidiosa vectoring sharpshooter species (H. coagulata, H. lacerta, and H. insolita) , but they were able to distinguish geographic populations of GWSS from Texas and California. In addition, certain markers were able to distinguish two populations of GWSS from California (Riverside and Bakersfield). This work showed that ISSR-PCR was the best DNA fingerprinting method to genetically characterize the GWSS. The development of molecular genetic markers for the GWSS set the stage for important genetic studies of the GWSS, such as identity of origin, genetic variation within and among populations, gene flow, and population/geographic structure. This work has been published in Annals of the Entomological Society of America. The experience gained with developing molecular genetic markers can now be used for other insect pests and plants. The second goal of the overall project was to develop molecular genetic markers for the egg parasitoids (Gonatocerus species) of GWSS. In FY2003, markers were developed that were able to distinguish three G. species (G. triguttatus, G. ashmeadi, and G. morrilli). In FY2004, we used ISSR-PCR to perform a geographic study of the GWSS with 19 populations that were arbitrarily divided into three regions (Southeastern, Southwestern, and Western). A second objective of this study was to attempt to determine the origin of the GWSS that invaded California. This study has determined the population genetic structure of the GWSS along with other genetic parameters. Our results determined that the origin of the GWSS that invaded California is Texas, contrary to the popular belief that it came from Florida. Furthermore, our results suggest that more than one founder event occurred in California. This work has been published in Annals of the Entomological Society of America. In our second goal of developing DNA markers for the GWSS parasitoid wasps, in FY2004 we identified markers by ISSR-PCR DNA fingerprinting that were able to determine geographic variation in the predominant GWSS parasitoid wasp (G. ashmeadi). For this study, a total of six populations were analyzed and geographic-specific markers were identified in certain populations. This finding is significant because the CDFA released these wasps in California collected from Louisiana, and J. de Leon identified Louisiana-specific G. ashmeadi markers. The identification of these molecular markers now allows us to monitor the success of establishment of these wasps released in California. This work has been published in the Journal of Insect Science. G. morrilli is another important egg parasitoid of the GWSS. We developed molecular markers (ISSR-PCR DNA fingerprinting and ITS2 amplification) that distinguished geographic populations of G. morrilli from California and Texas. The ISSR-PCR fingerprinting patterns were totally different in the two populations; in addition, the ITS2 amplification product sizes were different. These results, along with crossing studies and sequencing of standard genes [mitochondrial COI and COI and internal transcribed spacer region 2 (ITS2)], strongly confirm that G. morrilli exist in nature as cryptic species. Determining the origin (Texas) of the GWSS was extremely important in order to know where to collect natural enemies. In addition, accurate identification of natural enemies is crucial to the success of biological control programs. Choosing the correct G. morrilli geographic population, or rather the correct cryptic species, is crucial to the biological control program in California. The development of molecular diagnostic markers that distinguish the California and Texas G. morrilli species now allows us to import and monitor the establishment of these wasps. Importation of this Texas G. morrilli species has begun in collaboration with the California Department of Food and Agriculture (CDFA). This work has been published in the Journal of Insect Science. Diagnostic or SCAR (Sequenced Characterized Amplified Region and mitochondrial COI, COII) markers have been developed towards the GWSS for predation studies to identify key predators as an alternative form of biological control. These diagnostic markers were shown to be successful in detecting GWSS remains (eggs, adults) in predator gut contents. In addition, preliminary studies using the COI marker have proved fruitful in detecting GWSS in field-collected predators. Identifying predators of the GWSS is key to a successful multi-tactic biological control approach. Chemical Ecology: Progress was made on developing bioassays to assess the response of GWSS and its parasitoids to volatile and visual cues, and to assess the suitability of Solid Phase Microextraction (SPME) to collect and isolate putative bioactive compounds. Biological Control of Waterhyacinth: In four years of field sampling of waterhyacinth, this project illustrated the importance of environmental stress factors, especially variation in water use, water nutrient content, and plant biochemical measures, in determining the extent of damage caused by waterhyacinth weevils and plant pathogens, and the strength of associations between plant damage and successful biological control. The project revealed a positive association between waterhyacinth weevil damage and fungal infection on leaves. This association was not dependent on soluble protein, peroxidase, and available carbohydrate biochemical measures, as weevils did not show a preference for infected versus control plants. In small field plots, damage caused by the fungus was enhanced by prior infestation with weevils, and both weevils and fungi were required to reduce shoot densities in plots. Under controlled conditions, weevils were able to transmit spores to fungal culture medium. The potential impact of these results is that they could be used to improve biological control outcomes. Waterhyacinth weevils could be pre- inoculated with fungal plant pathogens prior to release into weed infestations. This accomplishment is consistent with the milestones under this project to evaluate and improve biological control of waterhyacinth, and with the goals under the 'Field Evaluation' and 'Combining Biological Control Agents' sections of Component IX (Biological Control of Weeds) of the NP304 Action Plan. This research also contributes to Goal 5 of the ARS Strategic Plan (Protect and enhance the nation's natural resource base and environment), specifically Performance Measure 5.2.1 (Develop the tools and techniques required to maintain the physical, chemical, and biological integrity of the Nation's watersheds and its surface and groundwater resources). Biological Control of Pigweeds: This project determined, for the first time, that abiotic stress factors related to weed-crop competition (drought and shading) influenced the size and plant water, protein, peroxidase, carbohydrate and free amino acid contents of Amaranthus palmeri, one of several species of pigweeds, which are important row crop weeds. Related studies demonstrated that cotton shows similar, though not identical, biochemical changes. The project showed that leaves on shade-stressed pigweed plants are preferred by beet armyworms for feeding and laying eggs. Larvae also preferred to feed on infected, symptom- bearing leaves vs. uninfected leaves on plants of pigweed species that are susceptible to two fungal plant pathogens that were investigated under this project as biocontrol agents. The potential impact of these results is that they could lead to modifications of protocols to monitor beet armyworms in crops to reflect the importance of abiotic stress and plant pathogens in modifying the quality of pigweeds as refuge hosts. This accomplishment is consistent with the milestones under this project to develop biological control options for pigweeds using plant pathogens within the context of crop production systems, and with the goals under the 'Integrated Weed Management in Cropland' section of Component X (Weed Management Systems) of the NP304 Action Plan. The research also contributes to Goal 3 of the ARS Strategic Plan (Enhance protection and safety of the Nation's agriculture and food supply), specifically Performance Measure 3.2.6 (Provide needed scientific information and technology to producers of agriculturally important plants in support of exclusion, detection, and early eradication; control and monitoring of invasive insects, weeds, and pathogens; and restoration of affected areas. Conduct biologically-based, integrated and areawide management of key invasive species). 6. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? Technologies developed by this project were transferred to appropriate users through conference presentations, journal publications, and other effective mechanisms. Technologies available for immediate utilization by other researchers include the sensitive DNA fingerprinting method, which will also work with any other insect and biological control program; much of the technology on DNA fingerprinting is already being used by other researchers both in the U.S. and abroad. We foresee no significant constraints to the continued acceptance by population genetics researchers in use of project-developed DNA fingerprinting technology to enhance progress in their own research programs. Semi-technical presentations to water and weed management groups in Texas provided up-to- date information on the status of waterhyacinth biological control and options for the future. A limitation on the transfer of technology involving plant pathogens as control agents is the need to mass-produce and properly formulate the pathogens to survive adverse environments. 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below). Moran, P.J. 2004. Biological control in South Texas: update on waterhyacinth, saltcedar, and Brazilian peppertree. Texas Noxious Weeds Working Group Meeting, October 21, 2004, Temple, Texas. Moran, P.J. 2005. Research on biological control of weeds at the USDA- ARS Beneficial Insects Research Unit, Weslaco, Texas. USDA-APHIS PPQ CPHST Lab Directors' Meeting, April 27, 2005, Mission, Texas. Moran, P.J. 2005. The use of weevils as vectors of fungal plant pathogens to improve biological control of waterhyacinth. Seminar to U.S. Army Corp of Engineers, Lewisville Aquatic Ecosystems Research Facility, May 2, 2005, Lewisville, Texas.

Impacts
(N/A)

Publications

  • De Leon, J.H., Jones, W.A., Morgan, D.J.W., Mizell, R.F., III. 2004. Sequence divergence in two mitochondrial genes (COI and COII) and in the ITS2 RDNA fragment in geographic populations of Gonatocerus morrilli, a primary egg parasitoid of the glassy-winged sharpshooter. In: Proceedings CDFA Pierce's Disease Control Program Research Symposium, December 7-10, 2004, San Diego, California. p. 322-325.
  • De Leon, J.H., Fournier, V., Hagler J., Daane K., Jones, W.A. 2004. Development of molecular diagnostic markers for Homalodisca sharpshooters present in California to aid in the identification of key predators. In: Proceedings CDFA Pierce's Disease Control Program Research Symposium, December 7-10, 2004, San Diego, California. p. 326-329.
  • Moran, P.J. 2005. Leaf scarring by waterhyacinth weevils (Neochetina eichhorniae and N.bruchi) enhances infection by the fungus Cercospora piaropi on waterhyacinth, Eichhornia crassipes. Biocontrol. 50(3):511-524.
  • Logarzo, G.A., Virla, E.G., Triapitsyn, S.V., Jones, W.A. 2004. Biology of zagella delicata de santis (hymenoptera:trichogrammatidae) egg parasitoid of tapajosa rubromarginata (signoret) (hemiptera:clypeorrhyncha:cicadellidae) in argentina. Florida Entomologist. 87(4):511-516
  • Fournier, V., Hagler, J.R., Daane, K., De Leon, J.H., Groves, R.L., Prabhaker, N., Costa, H. 2004. Identifying key predators of the various glassy-winged sharpshooter life stages. CDFA Pierce's Disease Control Program Research Symposium, 7-10 December 2004, San Diego, CA, pp. 97-99
  • De Leon, J.H., Jones, W.A., Morgan, D.J. 2004. Molecular distinction between populations of Gonatocerus morrilli, egg parasitoids of the glassy- winged sharpshooter Homalodisca coagulata, from Texas and California, Do cryptic species exist? Journal of Insect Science. 4:7.
  • De Leon, J.H., Jones, W.A. 2005. Genetic differentiation among geographic populations of Gonatocerus ashmeadi (Hymenoptera: Mymaridae), the predominant egg parasitoid of Homalodisca coagulata (Homoptera: Cicadellidae). Journal of Insect Science. 5:1-9.
  • De Leon, J.H., Jones W.A., Morgan, D.J.W., Mizell III, R.F. 2004. Genetic differentiation among geographic populations of Gonatocerus ashmeadi: A primary egg parasitoid of the glassy-winged sharpshooter. In: Proceedings CDFA Pierce's Disease Control Program Research Symposium, December 7-10, 2004, San Diego, California. p. 314-317.
  • De Leon, J.H., Jones, W.A., Morgan, D.J.W., Mizell, R.J. 2004. Extensive sequence divergence in the ITS2 RDNA fragment in a population of Gonatocerus ashmeadi from Florida: Phylogenetic relationships of Gonatocerus species. In: Proceedings of the CDFA Pierce's Disease Control Program Research Symposium, December 7-10, 2004, San Diego, California. p. 309-312.
  • De Leon, J.H., Jones, W.A., Morgan, D.J.W. 2004. Molecular distinction between populations of Gonatocerus morrilli, egg parasitoids of the glassy- winged sharpshooter, from Texas and California: Do cryptic species exist? In: Proceedings of the CDFA Pierce's Disease Control Program Research Symposium, December 7-10, 2004, San Diego, California. p. 318-321.


Progress 10/01/03 to 09/30/04

Outputs
1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter? Each year, new insect, mite, and weed pests enter the U.S. and add to the existing pest pressure on our food and fiber crops. Exotic and invasive insects and weeds cost the U.S. over $122 billion per year in crop losses and control costs. At a time when reduction in pesticide use is a national priority, the appearance of new pests challenges our ability to reduce pesticide use. The costs associated with trying to control these pests and the use of chemical pesticides makes agricultural products more costly and leaves behind potentially toxic residues. These issues are being resolved by this project through the development of new technologies that take advantage of the pests' own natural enemies to reduce damage in a sustainable manner. Naturally occurring predators, parasitoids, and diseases will be identified in their area of origin, then collected, imported, and evaluated for their ability to control the targeted pests. Recent techniques in molecular biology, biochemistry, and genetics will be integrated with conventional classical biological control techniques to develop new technological advances in the field of biological control. Aquatic weeds have invaded natural and man-made waterways around the world, resulting in destruction of local aquatic ecosystems as well as causing serious social and economic consequences; costs associated with aquatic weed control and lost revenues run into the millions for single U.S. states each year. Chemical control of weeds in many areas is prohibited by regulatory agencies. Invasive terrestrial weeds in crops and adjacent areas threaten crop production and scarce natural resources. This project contributes to the Crop Protection and Quarantine National Program (NP 304), and specifically addresses the Biology of Pests and Natural Enemies; Plant, Pest, and Natural Enemy Interactions and Ecology; Pest Control Technologies; and Biological Control of Weeds research components by providing new information regarding ecological interactions between exotic and invasive plant pests and crop production systems, and new technologies for more effective and environmentally friendly pest control. Portions of the research contribute to the Agroengineering, Agrochemical, and Related Technology component of the Crop Production National Program (NP 305) by supporting the goals and research needs of the glassy-winged sharpshooter (GWSS) program through development of improved glassy-winged sharpshooter monitoring and control technology. This work also contributes to the Genetic Resource Management; Genomic Characterization and Genetic Improvement; and Genome Databases and Bioinformatics components of the ARS National Program on Plant, Microbial, and Insect Genetic Resources, Genomics, and Genetic Improvement (NP 301) by collecting and preserving geographic populations of the GWSS, its relatives and natural enemies, with the ultimate goal of developing more productive and adaptable natural enemies for GWSS control. To facilitate achievement of project objectives, Specific Cooperative Agreements are in place with Texas A&M University and the University of California, Riverside; these collaborative arrangements provide access to scientific expertise and facilities not available in-house. The project is supported, in part, by outside funds via USDA-APHIS; these funds are facilitating progress of the work at an accelerated pace. Growers and consumers of crops affected by targeted pests will benefit from reduced pesticide use and the collateral problems associated with pollution. The nation's waterways will be cleaner and its water supply will be more available with aquatic weeds being effectively controlled by appropriate biological control organisms. 2. List the milestones (indicators of progress) from your Project Plan. Year 1 (FY 2003): 1. Collect exotic egg parasitoids of the glassy-winged sharpshooter in South America and ship to U.S. 2. Begin evaluation in quarantine. 3. Bioassay sharpshooter adults and parasitoids for behavior-modifying compounds. 4. Isolate and identify chemistry of bioactive compounds. 5. Collect DNA from sharpshooters and their egg parasitoids. 6. Develop molecular marking methods for identifying species and populations. 7. Complete studies of defense/stress via chemical changes in pigweed. 8. Bioassay beet armyworm on stressed/infected pigweed. 9. Initiate field study in cotton with pathogen-infected pigweed. Year 2 (FY 2004): 1. Continue collection of exotic egg parasitoids of the glassy-winged sharpshooter in South America and ship to U.S. 2. Continue evaluations in quarantine. 3. Continue bioassays of sharpshooter adults and parasitoids for behavior- modifying compounds. 4. Continue to isolate and identify chemistry of bioactive compounds. 5. Seek commercial partners for development and practical use of behavior- modifying compounds. 6. Determine the best treatment that enhances biocontrol of water hyacinth. 7. Complete first year of sampling water hyacinth. 8. Apply for permits to import novel biocontrol agents for weeds. 9. Complete bioassays of beet armyworm on stressed/infected pigweed. 10. Complete field study in cotton with pathogen-infected pigweed. Year 3 (FY 2005): 1. Complete molecular marker studies and transfer technology. 2. Complete field studies on defense/stress chemical changes in infected pigweed. 3. Complete field studies on infected/noninfected pigweed in cotton. 3. Milestones: A. List the milestones that were scheduled to be addressed in FY 2004. How many milestones did you fully or substantially meet in FY2004, and indicate which ones were not fully or substantially met, briefly explain why not, and your plans to do so. 1. Continue collection of exotic egg parasitoids of the glassy-winged sharpshooter in South America and ship to U.S. 2. Continue evaluations in quarantine. 3. Continue bioassays of sharpshooter adults and parasitoids for behavior- modifying compounds. 4. Continue to isolate and identify chemistry of bioactive compounds. 5. Seek commercial partners for development and practical use of behavior- modifying compounds. 6. Determine the best treatment that enhances biocontrol of water hyacinth. 7. Complete first year of sampling water hyacinth. 8. Apply for permits to import novel biocontrol agents for weeds. 9. Complete bioassays of beet armyworm on stressed/infected pigweed. 10. Complete field study in cotton with pathogen-infected pigweed. All of the FY 2004 milestones were fully met with the exception of #4 and #5. Candidate bioactive compounds were not identified because the collaborating chemist withdrew from the project, thus not allowing commercial partners to further develop candidate compounds. A new chemist partner is being recruited. B. List the milestones that you expect to address over the next 3 years. What do you expect to accomplish, year by year, over the next 3 years under each milestone? FY 2005 (Year 3): 1. Complete molecular marker studies and transfer technology. 2. Complete field studies on defense/stress chemical changes in infected pigweed. 3. Complete field studies on infected/noninfected pigweed in cotton. This project will expire in FY 2005 and will be replaced by a project currently under development and which will be submitted for review and approval via the OSQR process. Projected milestones under the replacement project, and expected accomplishments under these milestones, include: FY 2006 (Year 4): 1. Complete colonization of the glassy-winged sharpshooter: Finalize the plant species and environmental conditions that are best for rearing the insects. 2. Complete bioassays of bioactive compounds of leafhoppers and parasitoids: Take headspace air samples of sharpshooters on and off plants and identify their chemistry using GC-MS. 3. Amplify and subclone sharpshooter mt-COII genes: Sequence sharpshooter mitochondrial genes to perform phylogenetic studies. 4. Complete developing and testing crude DNA extract procedures: Decide on best extraction procedure that is fast and simple, allowing mass field screening. 5. Amplify and subclone parasitoid species mt-COII from different populations: Sequence this gene to genetically identify populations and determine if cryptic species exist. 6. DNA fingerprint parasitoid species with ISSR-PCR: Determine genetic structure and geographic variation that may be useful in identifying precise strains of parasitoids. 7. Amplify and subclone ITS-2 region from parasitoids: Sequence this gene to genetically identify populations and determine if cryptic parasitoid species exist. 8. Complete study on vectoring of water hyacinth pathogens: Repeat tests releasing water hyacinth weevils with pathogen spores to see if beetles transmit pathogens to plants. 9. Assess pheromone and volatile lures on saltcedar beetles: Beetle pheromone traps will be set up near release sites to determine if beetles are still present following release. 10. Complete studies on effects of pathogens on pigweeds in greenhouse: Final trials will be conducted using different pathogen doses on different species of pigweeds. FY 2007 (Year 5): 1. Search South America for additional species of GWSS parasitoids for California and Hawaii: Collect additional genetic material for the S. American parasitoid Gonatocerus tuberculifemer, and search for parasitoids in a climate similar to that of Hawaii. 2. Colonize new parasitoids in U.S. quarantine and conduct host range studies: Conduct host range studies on any new parasitoids discovered during latest searches. 3. Complete sequencing of sharpshooter mt-COII genes: Sequence this gene to see if it best genetically identifies populations and determines if cryptic species exist. 4. Complete sequencing ITS-2 regions from different sharpshooter populations: Sequence this gene to see if it best genetically identifies populations and determines if cryptic species exist. 5. Complete SCAR markers to detect all sharpshooter life stages: Refine sharpshooter-specific Sequenced Characterized Amplified Region (SCAR) PCR to detect sharpshooter stages in gut contents of specific predators. 6. Complete sequencing of COII genes from different sharpshooter species: Sequencing these genes will determine or confirm whether sharpshooters exist in nature as cryptic species. 7. Complete sequencing of mt-COII genes from cryptic parasitoid species: Sequence these genes to determine if they genetically identify populations and determine if cryptic species exist. 8. DNA fingerprint parasitoids with ISSR-PCR primer (B): Use Inter-Simple Sequenced PCR DNA fingerprinting method to finalize ability to distinguish various parasitoid species. 9. Complete study of vectoring of fungi and impacts on water hyacinth in tanks: Repeat releases of weevils with pathogen spores attached, to confirm if the beetles can spread the pathogen to the weeds. 10. Assess non-target effects on athel in field: Cage saltcedar beetles on athel, an ornamental and close relative of saltcedar, to determine if beetles will successfully reproduce. 11. Complete studies of new strains on pigweeds and insect feeding: Finalize greenhouse studies on dosage rates and pathogen strains on pigweeds and the effects of infected pigweed on feeding by beet armyworms. 4. What were the most significant accomplishments this past year? A. Single most significant accomplishment during FY 2004: Parasitic wasps that attack the eggs of the glassy-winged sharpshooter (GWSS), but not other leafhoppers, were discovered in Argentina. This is important because the parasitoids were collected from climate and habitat conditions that are identical to those found in grape-growing regions of California, indicating these wasps to be ideal candidates for GWSS control in the U.S. Scientists in the Beneficial Insects Research Unit at the Kika de la Garza Subtropical Agricultural Research Center, Weslaco, Texas, in collaboration with scientists at the South American Biological Control Laboratory, Buenos Aires, Argentina, used climate matching software to locate desired collecting areas to find parasitoids from closely related sharpshooters. If successfully established in California, one or more of these parasitoids could dramatically reduce sharpshooter populations, thus reducing its spread and, importantly, reducing the rate at which GWSS populations vector the deadly Pierce's disease that devastates grapes and other commodities. B. Other significant accomplishment(s): The genetic variation in the glassy-winged sharpshooter (GWSS) was defined, and was shown to vary significantly throughout its range. This accomplishment is important because it establishes that there are different GWSS biotypes, and because it will allow identification of the different geographic sources of sharpshooters. Scientists in the Beneficial Insects Research Unit at the Kika de la Garza Subtropical Agricultural Research Center, Weslaco, Texas, developed a new DNA fingerprinting method for application to the GWSS, applied the method to the characterization of 17 different GWSS populations, and established that the source of the California, Tahiti, and Hawaii infestations likely originated from insects in Texas. Knowing the origin of GWSS infestations is critical to ongoing work that will identify candidate biological control agents for control of the GWSS so as to minimize/prevent the destruction of California grapes by Pierce's disease. C. Significant activities that support special target populations: None. 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. Exotic egg parasitoids of the glassy-winged sharpshooter (GWSS) were discovered which offers great promise for reducing sharpshooter populations in California, and which in turn should reduce the rate of spread of Pierce's disease and also of the sharpshooter. Sensitive DNA markers were developed that can determine the geographic origin of species of egg parasitoids of sharpshooters; this accomplishment will revolutionize knowledge of how classical biological control works. With these tools, parasitoids collected from geographically different areas can be identified as to their source following release to allow determination of which source is most effective. All accomplishments made under this project are fully consistent with relevant milestones listed in the Project Plan, and with the relevant research components as defined in the National Program 304, 305, and 301 Action Plans. 6. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? Technologies developed by this project were transferred to appropriate users through conference presentations, journal publications, and other effective mechanisms. Technologies available for immediate utilization by other researchers include the sensitive DNA fingerprinting method, which will also work with any other insect and biological control program; much of the technology on DNA fingerprinting is already being used by other researchers both in the U.S. and abroad. We foresee no significant constraints to the continued acceptance by population genetics researchers in use of project-developed DNA fingerprinting technology to enhance progress in their own research programs. 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. Flores, A. 2003. South American biocontrols may tangle with glassy-winged sharpshooter. Agricultural Research. September, 2003. p. 18. Jones, W.A. 2003. The use of climate matching in a biocontrol program (oral presentation). Entomological Society of Brazil, June 22-26, 2003, Sao Pedro, Brazil. Jones, W.A. 2004. Importance of host range in classical biological control programs (oral presentation). University of Missouri, March 19, 2004. Columbia, Missouri. Jones W.A. 2004. The use of climate matching to locate natural enemies of a disease vector (oral presentation). International Plant Protection Congress, May 11-16, 2004. Beijing, China. de Leon, J.H., Jones, W.A., Morgan, D.J.W. 2003. Population genetic structure of the glassy-winged sharpshooter determined by ISSR-PCR DNA fingerprinting (oral presentation). Pierce's Disease Research Symposium, December 9-11, 2003. San Diego, California.

Impacts
(N/A)

Publications

  • Moran, P.J., Cheng, Y., Cassell, J.L., Thompson, G.A. 2003. Gene expression profiling of Arabidopsis thaliana in compatible plant-aphid interactions. Archives of Insect Biochemistry and Physiology. 51:182-203.
  • Moran, P.J. 2004. Feeding by waterhyacinth weevils (Neochetina spp.) (Coleoptera: Curculionidae) in relation to site characteristics, plant size and biochemical factors. Environmental Entomology. 33:346-355.
  • Showler, A., Moran, P.J. 2003. Effects of drought stressed cotton, Gossypium hirsutum L., on beet armyworm, Spodoptera exigua (Hubner), oviposition, and larval feeding preferences and growth. Journal of Chemical Ecology. 29(9):1997-2011.
  • De Leon, J.H., Jones, W.A., Morgan, D.J. 2004. Population genetic structure of Homalodisca coagulata (Homoptera: Cicadellidae) the vector of the bacterium Xylella fastidiosa causing Pierce's disease in grapevines. Annals of the Entomological Society of America. 97(4):1-10.
  • Kanga, L.H., Jones, W.A., Humber, R.A., Boyd, Jr., D.W. 2004. Fungal pathogens of the glassy-winged sharpshooter, Homalodisca coagulata (Say) (Homoptera: Cicadellidae). Florida Entomologist. 87:225-228.
  • Kanga, L.H., James, R.R., Jones, W.A. 2003. Field trials using the fungal pathogen, Metarhizium anisopliae (Deutermycetes: Hyphomycete) to control the ectoparasitic mite, Varroa destructor (Acari: Varroidae) in honey bee colonies. Journal of Economic Entomology. 96(4):1091-1099.