Grapevine ‘Variety Focus' lectures are now available on Foundation Plant Service's website at
These lectures, from 2005-2011, were given by a talented group of guest speakers including UC Davis faculty, UC farm advisors, experienced California growers and winemakers as well as guest speakers from the focus variety country of origin.
- Wine quality is affected by a very common disease, leafroll disease, which reduces sugar content and color of grapes and increases acidity. Leafroll disease is caused by one or more viruses in the grapevine leafroll virus species.
- Archived leaf tissue in the UC Davis Herbarium from the 1940s was found to be infected with the newly discovered (2012) Grapevine red blotch virus indicating that it has been around at least since then.
- Every year, over 100 grapevine selections are treated for virus elimination in NCPN-associated labs.
- NCPN-Grapes has the largest Tier 2 Committee – 21 members from industry, extension/research and state regulatory agencies representing the eastern and western US.
- NCPN-Grapes centers distribute more than 700,000 clean grape cuttings, buds, and plants to industry.
“The National Clean Plant Network is a valuable resource for our wine industry of Washington and other areas of the PNW and the nation. Virus-clean grapevine material from the Clean Plant Center Northwest (CPCNW) has given the Washington wine industry a future and direction in battling the most significant disease (Grapevine leafroll) facing the industry. This is important to me and many others for the long-term sustainability of our farming operations. We farm over 1300 acres of wine grapes and 250 acres of Concords and we cannot afford to overlook the significance of clean, virus-free planting material.
It is without any reservation that I support the NCPN and CPCNW because I know firsthand that the long-term sustainability of the wine grape industry depends on the availability of clean, virus-free grape plants.
In 2009 our farm removed 13 acres of Chardonnay (purchased from a reputable nursery) that we thought were certified and virus free. The Chardonnay vines were planted in 2006 and the planting/training costs of the first 3 years were just beginning to be recovered when we determined the vines were not clean but diseased with 2 viruses. On top of this, we had just propagated 10,000 vines from this same block the previous year, not knowing the vines were infected. We lost two-fold: existing vineyard and future planting. Since 2009 we have replaced 115 acres (11 blocks) of grapevine leafroll-infected vines that were low yielding and poor quality. This firsthand experience makes me a firm believer in the CPCNW—it is paramount to the future of our industry.”
Chris Bowland, grape grower and vineyard manager, Sonoma County, California
"I've had to replant a number of young vineyards due to unclean plant material. It's heartbreaking. Starting with known, clean material, is fundamental in maintaining the longevity of a vineyard.”
Kevin C. Judkins, Owner/Operator, Inland Desert Nursery, Benton City Washington
“Inland Desert Nursery is the largest grapevine nursery in the Pacific Northwest, delivering annually 2 million plus field-grown and green-potted vines to customers across North America. The National Clean Plant Network is critical to the future of our business. Having the support of the Clean Plant Center Northwest in Prosser WA and Foundation Plant Services in Davis CA is essential to our mission of providing clean vines to our clients.”
Dennis Rak, Double A Vineyards, New York
“Double A Vineyards is one of the largest grapevine nurseries in the East, with sales of over 100 varieties. The National Clean Plant Network is important to Double A Vineyards' future business success. Double A Vineyards is currently doubling their increase vineyards from 40 acres to 80 to supply the growing demand for grapes for planting east of the Rockies. NCPN will provide us a clean source of plant material for future plantings and will benefit the entire grape industry. This is not something we could do ourselves and the program is a great example of the industry working together for the benefit of all.”
Dr. Maher Al-Rwahnih took over the reins as Diagnostic and Research Lab Director at Foundation Plant Services (FPS), UC Davis on July 1, 2016. He also serves as vice chair of the NCPN-Fruit Tree Tier 2, is on NCPN-Roses Tier 2 and is actively involved in the NCPN-Sweetpotato virology committee.
Maher (pronounced Ma - her) originally hails from Jordan and spent time in Italy at the University of Bari and came to FPS in 2004 as a post-doc. We are very fortunate to have him in his new position as Lab Director on the FPS Team! We have certainly benefited from his research skills, organizational skills and great negotiating skills with equipment salespeople.
Al-Rwahnih (pronounced al – ra – wa – hnee) was a pioneer in applying Next Generation Sequencing (NGS is now called High Throughput Sequencing (HTS)) technology to a plant (grapevines). This was the first time a plant of any kind was analyzed by HTS. His work will have major benefits for regulatory agencies, clean plant programs and grape growers. His biography is at http://www.apsnet.org/members/awards/Hutchins/Pages/MaherAlRwahnih.aspx
The National Clean Plant Network for Grapes (NCPN-G) was established to improve the health and productivity of wine, juice, and table grape vineyards in the United States. Clean grapevines are the key to higher yields, higher quality fruit, and cost-effective, sustainable grape production. The five centers in the network represent grape growing regions across the country.
In March 2016, a weekly webinar series entitled NCPN Webinar Series: Clean Plants for the Future of the Eastern Wine and Grape Industry was hosted by Dr. Tim Martinson, Senior Extension Associate for Cornell University's Viticulture and Enology program. The subject was how the efforts of the National Clean Plant Network, new testing protocols, and a revitalized New York certification program will reduce the risk of nursery-transmitted viral pathogens. The series featured different speakers each week and was attended by people from across the U.S. as well as internationally. Presentations are posted at