Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: BIORATIONAL CONTROL METHODS FOR INSECT PESTS OF POTATO
2006 Annual Report


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? Why does it matter?
Economic losses to pest insects in northwest potato cropping systems are due substantially to green peach aphid and wireworms (larvae of click beetles) with additional impact caused by leafhoppers, mites, Colorado potato beetle, and moth caterpillars that defoliate potato. The potato tuber moth has recently become established in Oregon and Washington and is increasing in significance. Control of insects in potato is predominately by insecticide sprays. Many of these pesticides are under increasing regulatory pressure, and are of concern in relation to pesticide residues in food and water, environmental concerns for pesticides in air and water, and worker safety. Research is needed to develop non-insecticidal means for controlling these pests and to reduce the need for pesticides in potatoes. Focus at this laboratory has been with implementing biological control (parasites, predators, and pathogens), incorporating highly selective chemicals into control programs that augment or enhance biological control, developing and improving pest monitoring methods, and manipulating the natural chemical environment of the pests to disrupt life history processes.

The problem of economic loss due to green peach aphid may cause upward of $100 million in yield loss due to transmission of virus to potato each year. The most effective insecticides for controlling the aphid are on the priority list for review under the Food Quality Protection Act. Growers are concerned that loss of these products will lead to unacceptable levels of aphid and virus in commercial fields. Pesticide applications currently made regionally for control of aphids are credited with control of several secondary pests, such as defoliating caterpillars and Colorado potato beetle. Loss of products used against the aphid will undermine control efforts for these secondary pests. Wireworms are of increasing concern as a pest in Pacific Northwest potato cropping systems. Also, there are regulatory concerns for pesticides used against wireworms. These pests require an aggressive research program to provide farmers with safe, effective, and economical means of control. During the past 3 years, heavy losses to potato fields in the lower Columbia River Basin have been caused by the potato tuber moth, and this is expected to increase without additional pest control measures.

The research undertaken falls under National Program 304 Crop Protection and Quarantine.The project addresses four components of the National Program Action Plan:

Component II: Biology of Pests and Natural Enemies (Microbes) The development of effective IPM strategies depends upon an in-depth knowledge of the biology and ecology of pests and their natural enemies. For IPM to be successful, it is necessary to investigate the biology for each major arthropod pest and its natural enemies for each cropping system, including physiology, nutrition, mating, fecundity, life tables, and developmental processes that impact ecological interactions.

Component III: Plant, Pest, and Natural Enemy Interactions and Ecology It is critical for successful use of biologically-based control, as part of IPM, to increase our knowledge of insect and mite population dynamics and ecology, as well as multi-trophic interactions among the biotic components of agricultural production systems. Research is needed to define the ecology of pest complexes and to determine the impact of pest-plant-natural enemy interactions on the effectiveness of IPM systems, and to apply this knowledge to improve estimates of economic and action thresholds. In addition, this knowledge may be used to develop plant varieties that combine pest resistance while promoting natural enemy activity.

Component V: Pest Control Technologies Successful IPM depends upon the availability of an array of component technologies that can be effectively combined to achieve environmentally-safe pest management. Research areas that will be emphasized to achieve this goal include (1) sampling, monitoring, detection, and validation of pest populations, (2) efficient production, delivery and utilization of beneficial organisms used in biological control, (3) response measures to control emerging and invasive pests, (4) development of selective chemical control strategies including those for minor crops, and (5) alternative control tactics such as resistant varieties and cultural measures, and other biologically-based strategies.

Component VI: Integrated Pest Management Systems and Area wide Suppression Programs The implementation of IPM and Area wide pest management programs will provide producers with safe and economical food production systems, reduce environmental risk, conserve our natural resources, and increase the competitiveness of producers. Emphasis will be placed on the implementation of practical integrated crop protection and production systems that are suitable for widespread use by growers on multiple scales in traditional or specialized production systems.


2.List by year the currently approved milestones (indicators of research progress)
FY2005:

1. Develop methods to mark green peach aphid with antigenic proteins.

2. Evaluate effects of induced defenses on development of loopers on potato.

3. Isolate bacteria from wireworms, identify bacteria, identify bacterial species having plasmids, publish results.

4. Develop assay methods for screening carbon dioxide as an attractant for wireworms.

5. Demonstrate role of carbon dioxide as a wireworm attractant, publish results.

6. Describe leafhopper phenology, test leafhoppers and plants for phytoplasmas, conduct transmission studies.

7. Identify location of mating for wireworm females.

8. Complete spring baiting study for wireworms.

9. Survey naturally occurring pests on transgenic and unmodified potatoes in field assays conduct.

10. Refine bioassay methods to survey green peach aphid clones for insecticide resistance and test 75 clones from throughout Washington.

11. Evaluate predator attractants and habitat modification for control of potato pests.

12. Conduct trials on the use of mineral oils and Kaolin to control aphids.

13. Assess susceptibility of potatoes to BLTVA phytoplasma in the lab and greenhouse.

14. Isolate fungi from wireworms, formulate and test baits. Establish flea beetle colonies and develop bioassays.

FY2006:

1. Develop methods to mark green peach aphid with antigenic proteins.

2. Use antigenic markers to estimate average local movement distance of aphids.

3. Evaluate effects of induced defenses on development of loopers on potato.

4. Isolate bacteria from wireworms, identify bacteria, identify bacterial species having plasmids, publish results.

5. Genetically modify bacterial plasmids, determine stability of inserted genes, develop assays to determine effect of modified gut flora.

6. Develop assay methods for screening carbon dioxide as an attractant for wireworms.

7. Demonstrate role of carbon dioxide as a wireworm attractant, publish results.

8. Describe leafhopper phenology, test leafhoppers and plants for phytoplasmas, conduct transmission studies.

9. Identify location of mating for wireworm females.

10. Complete spring baiting study for wireworms.

11. Complete fall baiting study for wireworms.

12. Conduct field trials to determine wireworm seasonal phenology.

13. Survey naturally occurring pests on transgenic and unmodified potatoes in field assays conduct.

14. Field studies for wireworms.

15. Isolate fungi from wireworms, formulate and test baits. Establish flea beetle colonies and develop bioassays.

16. Evaluate predator attractants and habitat modification for control of potato pests.

17. Conduct trials on the use of mineral oils and Kaolin to control aphids.

18. Refine bioassay methods to survey green peach aphid clones for insecticide resistance and test 75 clones from throughout Washington.

19. Refine molecular markers of aphid resistance to pesticides, test their association with bioassay results, publish results.

20. Assess susceptibility of potatoes to BLTVA phytoplasma in the lab and greenhouse.

21. Develop purple top disease index for leafhopper action threshold.

FY2007:

1. Use antigenic markers to estimate average local movement distance of aphids.

2. Use antigenic markers to differentiate local movement from long distance movement by green peach aphid.

3. Evaluate effects of induced defenses on host finding behavior of loopers and aphid.

4. Genetically modify bacterial plasmids, determine stability of inserted genes, develop assays to determine effect of modified gut flora.

5. Demonstrate role of carbon dioxide as a wireworm attractant, publish results.

6. Determine concentrations of carbon dioxide necessary to attract wireworms.

7. Describe leafhopper phenology, test leafhoppers and plants for phytoplasmas, conduct transmission studies.

8. Identify location of mating for wireworm females.

9. Determine diel periodicity of wireworm mating.

10. Complete fall baiting study for wireworms.

11. Publish results for wireworm baiting.

12. Determine if spring or fall wireworm baiting provides more accurate predictor of tuber damage.

13. Conduct field trials to determine wireworm seasonal phenology.

14. Survey naturally occurring pests on transgenic and unmodified potatoes in field assays conduct.

15. Field studies for wireworms.

16. Isolate fungi from wireworms, formulate and test baits. Establish flea beetle colonies and develop bioassays.

17. Evaluate predator attractants and habitat modification for control of potato pests.

18. Conduct trials on the use of mineral oils and Kaolin to control aphids.

19. Develop purple top disease index for leafhopper action threshold.

20. Refine molecular markers of aphid resistance to pesticides, test their association with bioassay results, publish results.

21. Use suitable genetic markers to survey NW aphid populations for pesticide resistance.

22. Evaluate modes of action for aphid resistance patterns observed.

FY2008:

1. Use antigenic markers to differentiate local movement from long distance movement by green peach aphid.

2. Determine association between local aphid movement patterns and virus infections in potato fields.

3. Evaluate effects of induced defenses on host finding behavior of loopers and aphid.

4. Genetically modify bacterial plasmids, determine stability of inserted genes, develop assays to determine effect of modified gut flora.

5. Determine concentrations of carbon dioxide necessary to attract wireworms.

6. Describe leafhopper phenology, test leafhoppers and plants for phytoplasmas, conduct transmission studies.

7. Identify location of mating for wireworm females.

8. Determine diel periodicity of wireworm mating.

9. Publish results for wireworm baiting.

10. Determine if spring or fall wireworm baiting provides more accurate predictor of tuber damage.

11. Conduct field trials to determine wireworm seasonal phenology.

12. Publish results of wireworm monitoring.

13. Survey naturally occurring pests on transgenic and unmodified potatoes in field assays conduct.

14. Field studies for wireworms.

15. Isolate fungi from wireworms, formulate and test baits. Establish flea beetle colonies and develop bioassays.

16. Publish results for wireworm and flea beetle baits.

17. Evaluate predator attractants and habitat modification for control of potato pests.

18. Conduct trials on the use of mineral oils and Kaolin to control aphids.

19. Summarize data and publish results on aphid control.

20. Develop purple top disease index for leafhopper action threshold.

21. Publish results on leafhopper action threshold.

22. Use suitable genetic markers to survey NW aphid populations for pesticide resistance.

23. Evaluate modes of action for aphid resistance patterns observed.

24. Publish results on aphid resistance.

FY2009:

1. Determine association between local aphid movement patterns and virus infections in potato fields.

2. Evaluate effects of induced defenses on host finding behavior of loopers and aphid.

3. Publish results of wireworm monitoring.

4. Field studies for wireworms.

5. Isolate fungi from wireworms, formulate and test baits. Establish flea beetle colonies and develop bioassays.

6. Publish results for wireworm and flea beetle baits.

7. Summarize data and publish results on aphid control.

8. Publish results on leafhopper action threshold.

9. Use suitable genetic markers to survey NW aphid populations for pesticide resistance.

10. Evaluate modes of action for aphid resistance patterns observed.

11. Publish results on aphid resistance.


4a.List the single most significant research accomplishment during FY 2006.
CONTROL OF POTATO TUBERWORM WITH TRANSGENIC BT POTATO. NP 304, CROP PROTECTION AND QUARANTINE. Component V: Pest Control Technologies and Component VI: Integrated Pest Management Systems and Area wide Suppression Programs.

Efficacy of Bt potato was demonstrated against potato tuberworm. Scientists at the USDA-ARS, Yakima Agricultural Research Laboratory, Wapato, WA in collaboration with the Department of Crop and Soil Sciences, Michigan State University, evaluated the larvicidal activity of three Bt-modified strains of the Spunta potato variety and observed complete protection of plants and tubers. Bt-modified potato has the potential to control not only PTW and but also other lepidopteran pests of potato. It has the potential to drastically reduce the amount of insecticide used by growers.


4b.List other significant research accomplishment(s), if any.
CONTROL OF POTATO TUBER MOTH IN STORED TUBERS USING A BIOFUMIGANT. NP 304, CROP PROTECTION AND QUARANTINE. Component V: Pest Control Technologies and Component VI: Integrated Pest Management Systems and Area wide Suppression Programs.

The toxicity of a fungus to potato tuberworm was demonstrated. Scientists at the USDA-ARS, Yakima Agricultural Research Laboratory in Wapato, WA in collaboration with Agraquest (Davis, CA) are evaluating the fungus Muscodor albus, which produces a mixture of antimicrobial volatile organic chemicals, as a biofumigant of PTW. Adult PTW that were exposed to the fungus in chambers died. Newly hatched larvae were also affected by exposure to volatiles produced by the fungus. Applications of this fungus may be practical for control of PTW on potato in storage but application methods need to be addressed.

GUT FLORA OF THE PACIFIC COAST WIREWORM. NP 304, CROP PROTECTION AND QUARANTINE. Component II: Biology of Pests and Natural Enemies (Microbes).

The bacterial flora of the gut of the wireworm was characterized. Scientists at the USDA-ARS, Yakima Agricultural Research Laboratory in Wapato, WA surveyed and identified enteric bacteria of wireworms in Eastern Oregon and Washington that may be suitable for transformation to deliver insect specific toxin to wireworms. Although a rich diversity of bacteria were found, of special interest is the frequent presence of Bacillus megaterium, which was found at both sites. This bacterial species is a well known industrial workhorse with recombinants being used for biological remediation and other purposes. It will be a good candidate to accept plasmids that produce insecticidal toxins derived from Bacillus thuringiensis or other sources, that could support the production of a novel biorational control for the wireworm.

AN ATTRACT-AND-KILL DEVICE FOR CONTROL OF LOOPERS ON POTATO. NP 304, CROP PROTECTION AND QUARANTINE. Component V: Pest Control Technologies.

Control of adult looper moths was demonstrated in the field and in a screenhouse using an attract-and-kill system. Loopers are intermittent pests of potato and other vegetable crops that defoliate plants and reduce yield and tuber quality. Researchers at the USDA-ARS Yakima Agricultural Research Laboratory, Wapato, WA, in collaboration with scientists with Washington State University, Pullman, WA conducted large scale experiments with an attract-and-kill station comprised of a lure releasing a floral odor and a flower-mimicking target that was coated with a pesticide formulation. In treated plots and screen houses, 75-80% knockdown of moths and 95% reduction in numbers of eggs laid were achieved. This technique may provide the means to control these and other defoliating caterpillars with greatly reduced use of pesticides.

MOVEMENT OF GREEN PEACH APHID INTO POTATO FIELDS. NP 304, CROP PROTECTION AND QUARANTINE. Component II: Biology of Pests and Natural Enemies (Microbes).

A method was developed to track movements of green peach aphid into and within potato crops. Scientists at the USDA-ARS, Yakima Agricultural Research Laboratory developed a new method to monitor local movement of green peach aphid to test the contribution of these aphids in vectoring diseases to potato. Aphids are contaminated with inexpensive proteins sprayed on plants which are then detected by tests for protein antibodies. Over 50% of aphids caught above a small plot of marked potatoes were marked in our pilot tests conducted in August and September 2005.


5.Describe the major accomplishments to date and their predicted or actual impact.
National Program 304, Crop Protection and Quarantine.

Results of our research are used by vegetable growers and processors, and by scientists at other research institutions. Specific examples of our stakeholders include members of the Washington State Potato Commission, USDA-ARS laboratories at Fairbanks and Gainesville. Problems solved over the past two years include identification of the insect vector of potato purple top disease, determination that crop oils can be used against green peach aphid on potato, demonstration of the predictive use of an oatmeal bait for assessing potential for damage to potato from wireworms, demonstration of effectiveness of a Bt potato, volatile chemicals from a fungus, and of a virus against potato tuberworm. This new information has not yet led to any commercially available products, but we expect these accomplishments to potentially lead to commercial applications following additional development. Information on beet leafhopper vectoring of purple top disease has been shared with growers at numerous meetings and through grower publications. Growers are now able to prevent the spread of the disease by monitoring and responding to the presence of beet leafhoppers, which then require pesticide applications for control. Work on fungus volatiles is conducted under a CRADA with a company that is interested in pest control applications.


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?
Details of research results on wireworm baiting, and on beet leafhopper vectoring of purple top disease of potato were provided to growers at the Annual Research Reviews of the Washington State Potato Commission, the Washington State Potato Conference, meetings of the Pacific Northwest Vegetable Association, Washington State University field days, and through the grower publication Potato Progress and articles in Potato Country, and Potato Grower. Research results on chemical lures and attract-and-kill technology for defoliating caterpillars, on wireworm baiting, on beet leafhopper, and potato tuberworm were presented to other scientists at regional, national, and international meetings.


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).
Camelo, L., P. J. Landolt, and R. S. Zack. “Populations reductions in alfalfa looper with killing stations based on floral lures”. 65th Annual Pacific Northwest Insect Management Conference, Portland, OR. January 2006.

Horton, D.R. “Pacific coast wireworm: sampling studies and depth in soil profile”. Annual Meeting of the Pacific Northwest Vegetable Association, Pasco, Washington (Nov. 2005)

Horton, D.R. 2005. How deep are wireworms in the spring?. Potato Progress. V(12):2-4.

Horton, D.R. 2006. “Too many may be hiding in the deep”. Potato Country (April 2006).

Horton, D.R. “Wireworms: Baiting to predict damage and movement in the soil profile”. 45th Washington State Potato Conference, Moses Lake, Washington (Feb. 2006).

Lacey, L. A. “Microbial control of potato tuber moth”. Hermiston Farm Fair, Dec. 2, 2005.

Lacey, L. A. “Microbial control of the potato tuber moth (Lepidoptera: Gelechiidae)”. Washington State Potato Conference, Moses Lake WA, Feb. 7-9, 2006.

Landolt, P.J., Jensen, A. 2006. Potato tuberworm peromone trapping. Potato Progress. 6(1): 1-2

Munyaneza, J. “Beet leafhopper population dynamics and management of purple top disease in potatoes”. USDA-ARS Potato Field Day. Paterson, WA (July, 2005).

Munyaneza, J. “Beet leafhopper and purple top disease: 2005 Season Recap and New Research Directions”. 45th Annual Washington State Potato Conference and Trade Show, Moses Lake, WA (February, 2006).

Munyaneza, J. “Impact of the purple top disease on potato tuber processing quality”. Washington State University Potato Field Day, Othello, WA (June 2006).

Munyaneza, J. “Phenology of the beet leafhopper, major vector of the potato purple top phytoplasma in the Columbia Basin”. 89th Annual Meeting of Potato Association of America. Calgary, Canada (July, 2005).

Munyaneza, J. “Purple top disease and beet leafhopper-transmitted virescence agent (BLTVA) phytoplasma in potatoes of the Pacific Northwest of the United States”. Potato 2005 International Congress and Trade Show. Emmeloord, The Netherlands (September, 2005).

Munyaneza, J. 2006. “Research update: Potato purple top disease and beet leafhoppers in the Columbia Basin”. Potato Country 22: 28-29.

Munyaneza, J. “Susceptibility of different potato cultivars to the Columbia Basin purple top phytoplasma and its impact on potato tuber quality”. 90th Annual Meeting of Potato Association of America. Madison, WI (July, 2006).

Munyaneza, J. “Update on beet leafhoppers and the potato purple top disease in the Columbia Basin”. 32nd Oregon State University Farm Fair and Trade Show. Hermiston, OR (November, 2005).

Munyaneza, J. “Update on the Columbia Basin potato purple top phytoplasma and its insect vectors”. Annual Meeting of WERA-89 (Potato Virus Disease Control Western Coordinating Committee). Las Vegas, NV (March, 2006).

Wright, L. C., D. G. James, S. Castle, V. Reyna, P. J. Landolt, and C. Smithhisler. “Identification of cutworms on grape vines during the spring in south central Washington”. 65th Annual Pacific Northwest Insect Management Conference, Portland, OR. (January 2006).


Review Publications
Lacey, L.A., Neven, L.G. 2006. The potential of the fungus, Muscodor albus as a microbial control agent of potato tuber moth (Lepidoptera: Gelechiidae) in stored potatoes. J. Invertebr. Pathol. 91: 195-198.

Zack, R.S., Ruiter, D.E., Strenge, D.L., Landolt, P.J. 2006. Adult caddisfly (Trichoptera) phenology at the Hanford Reach National Monument, Washington State. Proceedings of the Entomological Society of Washington. 108(1): 131-138.

Munyaneza, J.E., Crosslin, J., Upton, J.E. 2006. The beet leafhopper (Hemiptera: Cicadellidae) transmits the columbia basin potato purple top phytoplasma to potatoes, beets, and weeds. Journal of Economic Entomology. 99(2): 268-272

Munyaneza, J.E. 2005. Purple top disease and beet leafhopper transmitted virescence agent (BLTVA) phytoplasma in potatoes of the Pacific Northwest of the United States. pp. 211-220. In: A. J. Haverkort and P. C. Struik [eds.], "Potato in progress: science meets practice". Wageningen Academic Publishers.

Munyaneza, J.E., Crosslin, J., Jensen, A.S., Hamm, P.B., Thomas, P.E., Pappu, H., Schreiber, A. 2005. Update on the potato purple top disease in the Columbia Basin. Proceedings of the 44th Annual Washington State Potato Conference. pp. 57-70.

Munyaneza, J.E., Upton, J.E. 2005. Beet leafhopper (Hemiptera: Cicadellidae) settling behavior, survival, and reproduction on selected host plants. J. Econ. Entomol. 98(6): 1824-1830.

Last Modified: 12/22/2014
Footer Content Back to Top of Page