Duration: 10/01/2003 to 09/30/2009

Administrative Advisor(s):

NIFA Reps:

Non-Technical Summary

Statement of Issues and Justification

Mission statement: NRSP5 is a national program committed to minimize the adverse effects of viruses in orchards of the United States by providing virus-free propagation material of important temperate tree fruit varieties from domestic and foreign sources through traditional and innovative methods of virus testing and therapy, and by forging collaborative relationships with government agencies, universities and industry to help maintain U.S. agricultural productivity, market competitiveness, balance of trade, and a diverse, wholesome and affordable food supply.

Statement of Issue and Justification:
Virus and virus-like agents of stone and pome fruit crops induce substantial economic loss to American consumers and to all sectors of the tree fruit industry (Attachment I Section I). Virus diseases directly impact grower efficiencies and economic viability, and indirectly affect family and community stability, balance of trade, and the supply of nutritious and diverse food supplied for consumers. Viruses like Plum pox virus cause severe diseases and have enormous economic and social impacts. More than 40 million dollars (D. Albright, USDA National PPV office, Carlisle, PA) have been spent by state and federal agencies to combat this virus since its arrival in the USA in 1999 (enough to fund NRSP5 at its current level for 160 years). Other insidious viruses like Prunus necrotic ringspot virus induce mild but sustained and significant losses over the life of the orchard that reduce or eliminate the sustainability of many orchard operations. The deleterious effects of most fruit tree viruses throughout the country are averted by clean stock programs dependent on NRSP5 and based on a cooperative effort between NRSP5, Land Grant Universities, state governments, and industry (Attachment I-Section II). The key role of NRSP5 in these relationships is reflected in the review document emerging from the external review of NRSP5 held in December 2002 (Attachment V-Section II).

For the U.S. tree fruit industry to remain competitive, virus containment strategies must not only be effective, they must also be efficient. During the first 30 years in the operation of this program, the variety situation in the industry was stable. In response to consumer demands and global opportunities and competition, growers of tree fruit are now in need of many new and diverse varieties, and they need them available quickly. Fruit and tree production from a new variety is most profitable during the first few years of its introduction. Through applied and basic research conducted at NRSP5, improved pathogen detection methods have reduced the times to clear new varieties from 10 years at the inception of the program to a little over one year at the present time. Continued reduction in residency in the program is needed.

Globalization of the tree fruit industry is a reality. NRSP5 is the vehicle through which new varieties from throughout the world are acquired and shared. Because of virus testing and therapy expertise located with NRSP5, the program evolved into the premier center (worldwide) for the international movement of new varieties. This makes the new varieties from breeding programs throughout the world readily available to our growers and nurserymen. Importation must be done safely to prevent introduction of exotic pests, but it must be rapid so supplies from other countries do not erode the domestic market. The most successful of the new generation of apple varieties originated in Japan (Fuji), New Zealand (Gala and Braeburn), and Australia (Pink Lady(r) brand (Cripps Pink variety)) and were imported through NRSP5's quarantine testing program. As Mr. Wallace Heuser, International Plant Management, Lawrence, MI, commented to the NRSP5 advisory committee in August, 2002, "Without NRSP5 I don't know where we'd be. I guess we'd be on the outside looking in."

Facilities to eliminate viruses from pome and stone fruit clones are limited. Although there are few places that can effectively screen new fruit tree varieties for a broad range of virus and virus like diseases, there are even fewer that can render infected clones free of virus contamination. Without this efficient service of therapy, apple varieties such as 'Fuji', 'Pink Lady(r) brand (Cripps Pink variety)' and many others would only be available as virus-infected clones. Production by our growers would suffer as a result. NRSP5 is the only site that provides this service in the United States, and there are only two or three other centers in the world where this work is effectively accomplished on a large scale (Attachment II).

Land grant Universities and State Certification Programs require external assistance. NRSP5 performs virus-sensitivity testing for new rootstocks being developed by breeding programs to reduce potentially harmful virus interactions after new rootstocks are released. NRSP5 provides economical virus-tested material for research projects. At one time, this was provided directly to university programs, but now those programs access most of this material indirectly through certified nurseries. NRSP5 provides diagnostic assistance to scientists and extension agents in response to disease symptoms in research plots and orchards. Several state regulatory agencies rely on NRSP5 to conduct virus assays and to retain varieties for their programs. It would be extremely expensive for each state to maintain similar expertise and services (Attachment II).

Stable funding is necessary to maintain collections of virus-free perennial clones and program integrity. Multistate research funds that are "off-the-top-funds" contributed by regional associations of State Agricultural Experiment Stations Directors and administered under guidance from USDA-CSREES provide approximately one-half of the almost $500,000 operating budget of NRSP5. One-quarter of necessary funding is in-kind contributions by Washington State University, and the remainder is service fees and grower commission grants. Even this four-pronged approach to funding is failing to keep pace with the costs of personnel retention, new technologies, and maintenance. New funding is needed to offset these costs and to replace or supplement current CSREES support. Industry is one possible source of additional funding. However, as costs for virus testing increase, the likelihood of certain members of industry by-passing such testing increases. That, in turn, increases the risk of virus outbreaks that will destabilize our fruit production areas. Funding considerations for NRSP5 must incorporate three important factors: 1) Expertise, facilities and equipment must be adequate. 2) The testing program must be construed as being non-biased with no direct vested interest in the testing results. Government funding provides this separation and helps maintain credibility with international and state government partners. 3) Program activities should be centralized for reasons of efficiency; no one state could afford to operate this program alone.

Prerequisite Criteria

How is the NRSP consistent with the mission?

How does the NRSP pertain to a national issue?

Rationale

Priority Established by ESCOP/ESS

Relevance to Stakeholders

Implementation

Objectives

1. Minimize the economic impact of viruses in the tree fruit and nursery industries by distributing virus-tested, commercially important clones of deciduous fruit trees from domestic and foreign sources.
   
2. Characterize causal agents associated with graft-transmissible diseases of unknown etiology to facilitate the development of rapid diagnostics and appropriate control measures.
   
3. In cooperation with state scientists, facilitate the development of virus control programs by identifying the pathogens associated with the disease, determining epidemiological properties, developing control strategies and assisting in their implementation.
   
4. Explore with other groups the merits of a coherent national certification program.
   
5. Develop alternate funding over the next 5 years with the help of agriculture research directors, industry and government agencies.
   
6. 
   

Projected Outcomes

Management, Budget and Business Plan

See Attachment IV.

Integration

Outreach, Communications and Assessment

1.NRSP5 research results are communicated by publication in scientific and trade journals and by presentations at industry meetings.
2.NRSP5 activities are explained and promoted by association with regional committees (WCC-020, NE-1006, ISHS Working Group, NAPPO tree fruit panel).

3.Activities of NRSP5 are communicated to regional industry leaders and Land-Grant University scientists and directors at NRSP5 annual meetings.

4.Activities of NRSP5 and related issues are available on the NRSP5 web page.

5.NRSP5 will add a half-time Information Specialist to assist in keeping the web site current and to assist in the preparation of project documentation.

6.NRSP5 participates in National Plant Board discussions on the merits and feasibility of a National Certification Program.

Projected Participation

Literature Cited

PUBLICATIONS (1997-2002)

Peer reviewed publications:
Theilmann J, Mozafari J, Reade JR, Wu Z, Xie W, Jesperson G, Bernardy M, Eastwell K, Rochon, D. 2002. Partial nucleotide sequence and genome organization of a Canadian isolate of little cherry virus and development of an ELISA-based diagnostic test. Phytopathology 92: 87-98.

Eastwell KC, Bernardy MG. 2001. Partial characterization of a closterovirus associated with apple mealybug-transmitted little cherry disease in North America. Phytopathology 91: 268-273.

Di Terlizzi B, Skrzeczkowski LJ, Mink GI, Scott SW, Zimmerman MT. 2001. The RNA 5 of Prunus necrotic ringspot virus is a biologically inactive copy of the 3' UTR of the genomic RNA 3. Archives of Virology 146: 825-833.

James D, Howell WE, Mink GI. 2001. Molecular evidence of the relationship between a virus associated with flat apple disease and cherry rasp leaf virus as determined by RT-PCR. Plant Disease 85: 47-52.

Pelchat M, Levesque D, Ouellet J, Laurendeau S, Levesque S, Lehoux J, Thompson DA, Eastwell KC, Skrzeczkowski LJ, Perreault JP. 2000. Sequencing of peach latent mosaic viroid variants from nine North American peach cultivars shows that this RNA folds into a complex secondary structure. Virology 271: 37-45.

Utkhede R, Nie J, Xu H, Eastwell K, Wiersma P. 2000. Transformation of biocontrol agent Enterobacter agglomerans with salicylate utilizing gene and its monitoring in orchard soil. Journal of Horticultural Science & Biotechnology 75:50-54.

Eastwell KC, Cossentine JE, Bernardy MG. 1999. Characterisation of Cydia pomonella granulovirus from codling moths in a laboratory colony and in orchards of British Columbia. Annals of Applied Biology 134:285-291.

Hammond RW, Crosslin JM, Pasini R, Howell W, Mink GI. 1999. Differentiation of closely related but biologically distinct isolates of Prunus necrotic ringspot virus by polymerase chain reaction. Journal of Virological Methods 80: 203-212

James D, Godkin SE, Rickson FR, Thompson DA, Eastwell KC, Hansen AJ. 1999. Electron microscopic detection of novel, coiled viruslike particles associated with graft-inoculation of Prunus species. Plant Disease 83: 949-953.

Bussiere F, Lehoux J, Thompson DA, Skrzeczkowski LJ, Perreault JP. 1999. Subcellular localization and rolling circle replication of peach latent mosaic viroid: Hallmarks of group A viroids. Journal of Virology 73:6353-6360.

Bechard J, Eastwell KC, Sholberg PL, Mazza G, Skura B. 1998. Isolation and partial chemical characterization of an antimicrobial peptide produced by a strain of Bacillus subtilis. Journal of Agricultural and Food Chemistry 46:5355-5361.

James D, Howell WE. 1998. Isolation and partial characterization of a filamentous virus associated with peach mosaic disease. Plant Disease 82: 909-913.

Rampitsch C, Eastwell KC. 1997. The complete nucleotide sequence of prune dwarf ilarvirus RNA?1. Archives of Virology 142:1911-1918.

Lowery DT, Eastwell KC, Smirle MJ. 1997. Neem seed oil inhibits aphid transmission of potato virus Y to pepper. Annals of Applied Biology 130:217-225.

Eastwell KC, Kalmar GB. 1997. Characterization of the interference between two comoviruses in cowpea. Journal of the American Society for Horticultural Science 122:163-168.

Eastwell KC, Jesperson GD. 1997. Little cherry disease control survey in British Columbia in 1996. Canadian Plant Disease Survey 77:91-92.

Damsteegt VD, Waterworth HE, Levy L, Mink GI, Howell WE. 1997. Prunus tomentosa as a diagnostic host for detection of plum pox virus and other Prunus viruses. Plant Disease 81: 329-332.

Published Conference Proceedings:
Lang GA, Howell W. 2001. Lethal sensitivity of some new cherry rootstocks to pollen-borne viruses. Acta Horticulturae 557: 151-154.

Howell WE, Eastwell KC, Li TSC. 2001. Heat treatment, chemo-therapy and hydroponic culture for obtaining virus-free trees of sweet cherry. Acta Horticulturae 550:455-458.

Skrzeczkowski LJ, Howell WE, Eastwell KC, Cavileer TD. 2001. Bacterial sequences interfering in detection of phytoplasma by PCR using primers derived from the ribosomal RNA operon. Acta Horticulturae 550:417-424.

Howell W, Skrzeckowski L. 1999. Occurrence and effects of peach latent mosaic viroid. Proceedings of the Washington State Horticultural Society, 94th meeting:214.

Howell WE, Burgess J, Mink GI, Skrzeczkowski LJ, Zhang YP. 1998. Elimination of apple fruit and bark deforming agents by heat therapy. Acta Horticulturae 472(2):641-646

Howell WE, Skrzeczkowski LJ, Mink GI, Nunez A, Wessels T. 1998. Non-transmission of apple scar skin viroid and peach latent mosaic viroid through seed. Acta Horticulturae 472(2):635-640.

Eastwell KC, Bernardy MG. 1998. Relationship of cherry virus A to little cherry disease in British Columbia. Proceedings of the 17th Symposium on Fruit Tree Virus Diseases, Acta Horticulturae 472:305-313.

Hammond R, Howell WE, Mink GI, Crosslin JM. 1998. Strain-specific polymerase chain reaction assays for discrimination of Prunus necrotic ringspot virus isolates. Acta Horticulturae 472(1):235-242.

Damsteegt VD, Stone AL, Waterworth HE, Mink GI, Howell WE, Levy L. 1998. The versatility of Prunus tomentosa as a bioindicator of viruses. Acta Horticulturae 472(1):143-146.

Eastwell KC, Lambert S. 1998. Cherry leafroll virus and the decline of cherry trees: a first report in Washington State. Washington State Horticultural Association - Proceedings of the 94th Annual Meeting, 206.

James D, Howell WE. 1998. Identification of a flexuous virus associated with peach mosaic disease. Acta Horticulturae 472(1):285-290.

Lang G, Howell W, Ophardt D. 1998. Sweet cherry rootstock/ virus interactions. . Acta Horticulturae 468:307-311.

Lang G, Long L, Howell WE. 1998. Sweet cherry genotype research consortium ? an interdisciplinary evaluation project. Acta Horticulturae 468: 191-198.
Howell WE, Mink GI. 1997. NRSP5/IR2 Home Page. Proceedings of the Washington State Horticultural Society 85: 152.

Contributions to books and monographs:
Eastwell KC. 2000. Little cherry virus. In: Global Crop Protection Compendium, 2nd Edition. G. Meyers, ed. Oxon, UK: CAB International.

Howell WE, Mink GI. 1998. NRSP-5/IR-2 Program to develop and distribute virus-tested deciduous fruit tree clones. In: Containment Facilities and Safeguards for Exotic Plant Pathogens and Pests. American Phytopathological Society: St. Paul, Minn, p157-160.

Howell WE. 2000. Cull Piles. In: Encyclopedia of Plant Pathology. OC Maloy, TD Murray, eds. John Wiley & Sons, Inc. NY, Vol. 1, pages 173-274.

Howell WE. 2000. Roguing. In: Encyclopedia of Plant Pathology. OC Maloy, TD Murray, eds. John Wiley & Sons, Inc. NY, Vol. 2, pages 869-870.

Howell WE. 2000. Sanitation. In: Encyclopedia of Plant Pathology. OC Maloy, TD Murray, eds. John Wiley & Sons, Inc. NY, Vol. 3, page 881.

Mink GI, Wample R, Howell WE. 1998. Heat treatment of perennial plants to eliminate phytoplasmas, viruses, and viroids while maintaining plant survival. In: Plant Virus Disease Control. American Phytopathological Society: St.Paul, Minn, p. 332-345.

Mink GI. 1998. Virus certification of deciduous fruit trees in the United States and Canada. In: Plant Virus Disease Control. American Phytopathological Society: St.Paul, Minn, p. 294-300.

Eastwell KC. 1997. Little cherry disease - in perspective. IN: Filamentous viruses of woody plants. Monette P, ed. Research Signpost Press, pp. 143-151.

Other:
Eastwell KC, Bernardy MG. 2001. Little cherry closterovirus putative RNA-dependent RNA polymerase gene, partial CDS. Genbank Accession number AF295922.

Published abstracts:
Howell WE. 2001. NRSP5 and the international exchange of cherry clones. Program and Abstracts of 4th International Cherry Symposium. Hood River, Oregon.

Lang GA, Howell WE. February, 2001. Lethal sensitivity of some new cherry rootstocks to pollen-borne viruses. 7th International Symposium on Orchard and Plantation Systems, Nelson, New Zealand.

Howell WE, Eastwell KC, Li TSC. 2000. Alternate methods to deliver antiviral compounds for establishing virus-free trees. 18th International Symposium on Virus and Virus-like Diseases of Temperate Fruit Crops Program, page 51.

Eastwell KC, Lambert S. 1998. Cherry leafroll virus and the decline of cherry trees: a first report in Washington State. Washington State Horticultural Association - Proceedings of the 94th Annual Meeting, page 206.

Damsteegt VD, Waterworth HE, Levy L, Mink GI, Howell WE. 1997. The versatility of Prunus tomentosa as a bioindicator of stone fruit viruses. 17th International Symposium On Tree Fruit Virus Diseases, Bethesda, MD, page 122.

Eastwell KC, Bernardy MG. 1997. Relationship of Cherry virus A to little cherry disease in British Columbia. 17th International Symposium On Tree Fruit Virus Diseases, Bethesda, MD, page 118.

Hammond R, Crosslin JM, Mink GI, Howell WE. 1997. The design of strain-specific polymerase chain reactions for discrimination of Prunus necrotic ringspot virus isolates. 17th International Symposium On Tree Fruit Virus Diseases, Bethesda, MD, page 37.

Howell WE, Skrzeczkowski LJ, Yuan Z, Mink GI. 1997. Non-transmission of deciduous fruit tree viroids through seed or by knives during bud propagation. 17th International Symposium On Tree Fruit Virus Diseases, Bethesda, MD, page 92.

Howell WE, Zhang YP, Burgess J, Mink GI, Skrzeczkowski LJ. 1997. Heat therapy for elimination of apple fruit and bark deforming agents. 17th International Symposium On Tree Fruit Virus Diseases, Bethesda, MD, page 160.

James D, Howell WE. 1997. Identification of a flexuous virus associated with peach mosaic disease. 17th International Symposium On Tree Fruit Virus Diseases, Bethesda, MD, page 75.

Lang G, Howell WE, Ophardt D, Mink GI. 1996. Biotic and abiotic stress responses of interspecific hybrid cherry rootstocks. 6th International Symposium on Integrating Canopy, Rootstock and Environmental Physiology in Orchard Systems, Penticton, B.C. Canada.

Lang G, Howell W, Ophardt D. 1997. Sweet cherry rootstock tests for virus sensitivity. International cherry meetings, Oslo, Norway.

Lang G, Howell W, Ophardt D. 1997. Sweet cherry rootstock tests for virus sensitivity. Proceedings of the Washington State Horticultural Association, p173.

Nemchinov L, Hadidi A, Verderevskaya TD, Howell WE, Mink GI. 1997. Polymerase chain reaction detection of apple stem pitting virus from herbaceous and pome fruit hosts. 17th International Symposium On Tree Fruit Virus Diseases, Bethesda, MD, page 150.

Skrzeczkowski LJ, Howell WE, Herd-Wentz B, Mink GI. 1997. Field survey for peach latent mosaic viroid (PLMVd) in the USA. 17th International Symposium On Tree Fruit Virus Diseases, Bethesda, MD, page 73.

Skrzeczkowski LJ, Howell WE, Herd-Wentz B, Mink GI. 1997. Seasonal detection of peach latent mosaic viroid (PLMVd) by tissue print hybridization. 17th International Symposium On Tree Fruit Virus Diseases, Bethesda, MD, page 91.

Skrzeczkowski LJ, Howell WE, Eastwell KC. 2000. Bacterial sequences interfering in detection of phytoplasma by PCR using primers derived from the ribosomal RNA operon. 18th International Symposium on Virus and Virus-like Diseases of Temperate Fruit Crops Program, page 28.

Wu Z, Eastwell KC, Rochon D. 1997. Molecular cloning and partial characterization of little cherry virus. Canadian Phytopathological Society British Columbia Regional Meeting, Summerland, British Columbia. Canadian Journal of Plant Pathology 20:345.

Xu H, Eastwell KC. 1997. Dot blot analysis and ELISA for detection of little cherry closterovirus isolates from infected cherry trees in British Columbia. American Society for Virology, 16th Annual Meeting, Bozeman, MT.

Miscellaneous:
Eastwell K. 2001. Keeping fruit trees virus-free: NRSP5's role in tree fruit production. Agrichemical and Environmental News 184:4-5.

Howell WE, Lang GA. 2001. Virus sensitivity of new sweet cherry rootstocks. Compact Fruit Tree 34(3):78-80.

Howell WE. 2001. Cull Piles. Encyclopedia of Plant Pathology, editors OC Maloy & TD Murray. John Wiley & Sons, Inc. NY, Vol.1, pages 273-274.

Howell WE. 2001. Roguing. Encyclopedia of Plant Pathology, editors OC Maloy & TD Murray. John Wiley & Sons, Inc. NY, Vol. 2, Pages 869 - 870.

Howell WE. 2001. Sanitation. Encyclopedia of Plant Pathology, editors OC Maloy & TD Murray. John Wiley & Sons, Inc. NY, Vol.2, page 881.

Aichele M, Howell WE. 2000. Plum pox virus. What's growing on? 12 (1): 5.
Howell, WE. 2000. National Research Support Project #5 and its relationship to the California Certification Program. IAB News 9: 5-6

Howell WE, Eastwell KC. 1998. Improved protocols for obtaining fruit tree varieties. Good Fruit Grower 49: 51-52.

Invited presentations:
Eastwell KC. 1998. Identifying and managing viral diseases in cherries. Yakima Fieldperson's Meeting, Yakima, WA.

Eastwell KC. 1999. NRSP-5: Your National Program. Southeastern Professional Fruit Worker Meeting. Columbiana, AL.

Eastwell KC. 1999. Peach Latent Mosaic Viroid - Where is it and how do we find it? Southeastern Professional Fruit Worker Meeting, Columbiana, AL

Eastwell KC. 2000. Cherry disorders caused by viruses and virus-like agents. Stadelman's Cherry Growers Annual Meeting, Sunnyside, WA.

Eastwell KC. 2000. Incidence of cherry leafroll virus in the Washington industry and its implications for cherry production. Northwest Nursery Improvement Institute, Yakima, WA.

Eastwell KC. 2000. Virus-induced decline of sweet cherry trees in Washington State. Cherry Institute, Yakima, WA.

Eastwell K. 2001. Cherry virus control: prescription for success. Washington Pest Consultants Association, Yakima, WA, Nov 15.

Eastwell K. 2001. Cherry virus problems in the PNW. 58th Annual Cherry Institute Grower's Meeting, Yakima, WA, Feb 5.

Eastwell KC. 2001. Virus diseases of cherry in the PNW and their control. L.E. Long, OSU Extension Service Short Course on Cherry Pathology, The Dalles, OR, Dec 6.

Eastwell KC. 2001. Viruses and their control in Washington State. Columbia Basin Crop Consultants Association, Moses Lake, WA, June 7.

Eastwell KC. 2002. Cherry viruses and their control. Stadelman's Cherry Growers Annual Meeting, Zillah, WA, Jan 9.

Eastwell KC. 2002. Cherry leafroll virus. Washington State Department of Agriculture, Mar 11.

Eastwell KC. 2002. Cherry virus update and their potential impact. Cherry Institute, Yakima, WA, Jan 11.

Eastwell KC. 2002. Cherry viruses in the PNW and their control. Big Bend Horticultural Society, Pasco, WA, Feb 12.

Eastwell KC, Howell WE. 2000. Plum Pox Virus. Stone Fruit Day, Buena, WA. Feb.

Eastwell KC, Howell WE, Gritsenko M. 2001. Protecting Pacific Northwest cherry orchards from serious virus threats. Washington/Oregon Tree Fruit Research Commission Research Review, Wenatchee, WA, Nov 8.

Eastwell KC, Howell WE, Bush, M. 2002. Cherry leafroll virus. Washington State University Cooperative Extension Field Day, July 18.

Eastwell KC, Howell WE. 2002. Cherry leafroll virus and its impact. Northwest Nursery Improvement Institute, June 6.

Howell WE, Mink GI. 1997. NRSP5/IR2 and virus research. Chilean growers, nurserymen and INIA officials, Santiago, Chile, Jan.

Howell WE, Mink GI. 1997. Testing for virus using Biological indicators. Shaanxi Research Institute, Xian, China, Apr.

Howell WE, Mink GI. 1997. Virus testing at NRSP5. National Meeting for Fruit Tree Pathologists, Xian, China, May 2.

Howell WE. 1997. NRSP5 & importation regulation progress. Prunus Clonal Germplasm Committee, Fayetteville, AR, June.

Howell, WE. 1998. New importation procedures. Northwest Nursery Improvement Institute/International Dwarf Fruit Tree Association Meetings, Pasco, WA, Feb.

Howell, WE. 1998. WSU and NRSP5 fruit tree virus research. IDFTA, Prosser, WA, Feb.

Howell, WE. 1998. NRSP5 funding. NNII, Dec.

Howell, WE. 1998. New importation protocol. Apple Clonal Germplasm Committee, Corvallis, OR, Nov.

Howell, WE. 1999. NRSP5 functions and needs. Washington Tree Fruit Task Force, Wenatchee, WA, Feb. 23.

Howell WE. 1999. Techniques of virus diagnosis for certification of pome fruit trees in the USA. International Congress on Fruit Tree Certification for South America. Santiago, Chile, Dec 13.

Howell WE. 1999. Status and financing of certification programs for deciduous fruit trees in the USA. International Congress on Fruit Tree Certification for South American. Santiago, Chile, Dec 14.

Howell WE. 1999. Production of certified pome fruit trees in the USA. International Congress on Fruit Tree Certification for South American. Santiago, Chile, Dec 14.

Howell WE. 1999. Diagnosis of virus and virus-like diseases of fruit trees in the USA for certification. South American Regulatory Official?s Workshop, SAG, Santiago, Chile, Dec 15.

Howell WE. 1999. Plum pox virus. Northwest Nursery Improvement Institute, Wenatchee, WA, Dec 6.

Howell WE. 1999. NRSP5. WSU-Prosser, June 29.

Howell WE. 1999. NAPPO as it affects NNII nurseries. Northwest Nursery Improvement Institute. McMinville, OR, Sept 1.

Howell, WE. 2000. New apple cultivar for high altitude growing areas in arid climate. Cowiche Hort Day, Cowiche, WA, Feb.

Howell, WE. 2001. Implications of decisions by the North American Plant Protection Organization. Northwest Nursery Improvement Institute, Grand Rapids, MI, Feb.

Howell WE. 2001. NRSP5 and the international exchange of cherry clones. International Cherry Research Symposium. Hood River, Oregon, June.

Howell, WE. 2001. Certification as a standard practice in the production of pome and stone fruit trees. Northwest Nursery Improvement Institute, Wenatchee, WA, Oct.

Howell, WE. 2001. Certification as an official control mechanism to limit pest importations and spread of PPV. NE 1006 Meeting, St. Catharines, Ont., Canada, Nov.

Howell, WE. 2001. Certification as a tool for use by pome and stone fruit tree nurseries. Northwest Nursery Improvement Institute, Wenatchee, WA, Dec.

Howell WE, Lewis, K, Bush, M. 2002. Cherry leaf roll virus. Washington State University Cooperative Extension Field Day, Aug 5.

Attachments

Land Grant Participating States/Institutions

Non Land Grant Participating States/Institutions