NE1020: Multi-state Evaluation of Winegrape Cultivars and Clones
(Multistate Research Project)
NE1020: Multi-state Evaluation of Winegrape Cultivars and Clones
Duration: 10/01/2004 to 09/30/2017
Statement of Issues and Justification
Grapes are the leading fruit crop in the United States (U.S.). The U.S. is the fourth leading producer of grapes in the world. Latest USDA statistics (2000) show 946,450 acres of grapes (31.6% of all fruit acreage), compared to 830,000 acres of oranges (26 % U.S. total fruit acreage) and 444,700 acres of apples (14.8 % of total). Grapes are grown for many uses, but wine is the most important use. Percent utilization of U.S. produced grapes in 2001 in order of increasing use was: canning (0.4%), non-fermented juice (5.8%), fresh table grapes (13.1%), dried for raisins (25.3%) and wine (55.2%). The farm gate value of grapes in 2000 was over 3 billion dollars (36.3% of total non-citrus fruit value). As a processed use wine production adds considerable value.
The market for wine grapes is increasingly global. A large share of the global wine market is based upon a few specific cultivars that consumers associate with high quality including, Cabernet Sauvignon, Chardonnay, Merlot, Pinot noir, Sauvignon blanc, and Syrah (Shiraz). Probably another 10 - 20 cultivars are recognized as being capable of producing superior quality table wine. There is considerable resistance in the world market to non-traditional cultivars. No wine cultivars developed through traditional breeding programs in the 20th or 21st century has become recognized in the international market place. Instead focus has been on improving the quality of a small set of cultivars that have been grown for hundreds of years.
Clonal selection programs have improved quality parameters of traditional wine grape cultivars. These programs identified differences in performance within a cultivar that is caused by genetic mutations and changes in gene expression. This clonal variation is most often found in cultivars that have a long history of cultivation. Parameters that can vary between clones include yield, vigor, disease resistance, morphology, fruit quality, and wine making potential. For the most part, these clonal development programs have been European.
USDA provided funds to establish a grape quarantine center at the University of California, Davis, to enable grower access to this pool of improved germplasm. As a result, U.S. wine grape growers now may select from a great diversity of clones of the major grape growing cultivars. However, there is little research information available about the performance of these wine grape clones in the many wine grape-growing regions of the U.S. Research is particularly needed on the performance of existing clones of wine grapes under U.S. growing conditions that differ from European conditions due to both environmental and economic factors.
In addition to these "Global" cultivars, there are other winegrape cultivars whose quality greatly respected on a regional basis. There are two reasons that these lesser known cultivars need to be evaluated in the U.S. First, the greatly expanded world supply of the primary global cultivars has, in some cases, produced an oversupply. The market saturation of the major cultivars causes even regions with established reputations to be interested in developing new products (varietal wines) to expand or maintain sales. Second, there is great potential for minor traditional cultivars from the old world to produce superior wines in the U.S. In some cases these cultivars may be best adapted to newly emerging grape production areas.
In addition, the major global cultivars are all Vitis vinifera cultivars. Because of climatic or disease restrictions there are wine grape growing regions of the U.S. that rely on non-Vinifera grapes or on inter-specific hybrids. These regions will improve their economic viability of their wine industries with information about the performance of new varietal material suitable to their growing conditions. The value of each successful introduction brings long-term benefits to the grower and winery community. For instance, the 1999 New York farm-gate value of the Geneva-bred inter-specific wine grape cultivar, Cayuga White (Einset and Robinson, 1972) was $344,860 (860 tons harvested at $401/ton). On the retail market, Cayuga White wine accounted for annual sales in the range of $4 to $5 million dollars between 1995 and 1999.
This research project will test the performance of clones of the major global cultivars and of new or previously neglected wine grape cultivars in the different wine grape growing regions within the U.S. This work will improve the competitiveness of U.S. grape growers and wineries by providing performance and quality information that is much needed for planting decisions.
Multistate funding for this project will constitute only a small fraction of the support required for this project. Funds will be leveraged through the Viticulture Consortium (East and West), a special program within USDA/CSREES administered by Cornell University and Penn State in the East and University of California in the West. Funds will also be generated from the American Vineyard Foundation as well as individual state grape and wine research programs. Finally, this project has been supported by WineAmerica, an advocacy organization for the grage and wine industry. WineAmerica will use this project as an example of strong multistate cooperation, which should allow enhancement of the Viticulture Consortium funding.
Related, Current and Previous Work
Improvements in the productivity and quality of wine have been achieved over the history of winemaking in the United States by both the introduction and creation of new plant materials. A review of work in this important field must include consideration of varietal diversity, virus disease status, and clonal evaluation. In addition, federal quarantine regulations and the availability of facilities for importation have played a major role in the history of this work in the United States.
In California, new and interesting selections of wine grapes, table grapes and rootstocks were collected by founding faculty members Hilgard and Bioletti, in collections that were maintained on the University of California (UC) campus, the Davis farm (which later became UC Davis and home of FPMS), and in experimental demonstration vineyards around the state (Amerine, 1982). As grape growing grew more technical and sophisticated in California, reports began to surface that the productivity and quality of some vineyards was being reduced by the presence of virus diseases; furthermore, many grapevine selections in commerce were mislabeled or incorrectly identified. Dr. Harold Olmo, a UC Davis faculty member in the Viticulture and Enology Department (VEN), lead efforts to establish collections of grapevines on the Davis campus that were selected for longevity, vigor, and fruitfulness. By 1952, the California Grape Certification Association was formed to develop, maintain, and distribute virus-tested and correctly-identified grape stock (Olmo, 1953). The collection was initially managed by C.J. Alley, a student of Dr. Olmos who went on to become part of the UCD Viticulture and Enology Department faculty. By 1958, this program was combined with the UC Davis disease-tested fruit and nut tree program to become Foundation Plant Materials Service (FPMS). This was the first source of virus tested, certified stock available to growers in the United States.
Outside of New Mexico and Arizona, where the first successful plantings of V. vinifera were established by Spanish missionaries, and California, repeated attempts to introduce European grapes failed because of hostile climates, phylloxera root aphids and serious diseases not found in Europe. In the 19th Century, efforts were begun in the U.S. and abroad to cross native grape species with European cultivars to combine resistance and quality factors. As a result, grape breeding programs and major grape collections were developed in states ranging from Texas to North Dakota and throughout the east.
Because there were no sources of resistance to Pierce's Disease in euvitis, southeastern efforts centered on domestication and improvement of V. rotundifolia, the muscadine grape. Important breeding programs were established in North Carolina, Georgia, and Florida. A federal program was established in Mississippi.
In the northern states, most success was obtained by combining V. labrusca, V. vinifera and lesser amounts of other species (Hedrick, 1908). These new cultivars were widely planted and offered for sale as both fresh and processed fruit throughout the eastern states. Fresh sales declined when more desirable V. vinifera fruit became available after the development of refrigerated shipping. The eastern industry became centered on the production of unfermented juice, dessert wine production and sparkling wine production. Public euvitis breeding continued in New York, North Carolina, Virginia and Arkansas (Pool, et al., 1976). Simultaneously parallel wine grape breeding efforts were being carried out in Europe. Because the Europeans did not appreciate the flavor contributed by V. labrusca, they used a different spectrum of species. Their primary aim was to produce cultivars that were suitable for dry, table wine production.
These European hybrids were collected and tested in Maryland, Geneva, NY and Vineland, Ontario, Canada (Pool et al., 1976). Beginning in the late 1960s, U.S. wine markets changed rapidly. Overall wine sales increased dramatically, but sales of dessert wines slumped. This put great pressure on eastern wineries to begin dry, table wine production. A wide-scale testing and planting of the European hybrids was followed by renewed efforts of American breeders to produce resistant cultivars suitable for dry wine production. The first of these, Cayuga White, was released at Geneva, NY in 1972 (Einset and Robinson, 1972). Major wine interspecific wine grape breeding continues in Geneva, NY; Vineland, Ontario; Fayettville, AR; and Summerland, British Columbia. At the same time that these newly focused breeding efforts started, others began to re-explore the potential for V. vinifera production in the eastern states. Armed with phylloxera resistant rootstocks, improved understanding of pests, improved pest management tools and the availability of virus-tested planting material, researchers showed that commercial production was feasible and that the resultant wines were of commercial quality (Pool et. al., 1976). Major programs to evaluate V. vinifera cultivars and clones were established at Geneva, NY, Prosser, WA (Clore et al. 1976) and Corvalis, OR. Each of these states is now a major producer of European grape wines.
The availability of better adapted V. vinifera and the improved quality of the new interspecific hybrid grapes combined with greatly expanded interest in wine resulted in establishment of vineyards and wineries in many non-traditional wine growing areas. In many cases these ventures were started because operators of smaller farms needed a value-added option to attain profitability. There are now commercial wineries in all 50 United States. Continued growth and competitiveness of these enterprises requires understanding and availability of the available clone and cultivar options.
During the 1980s and 90s, important expansions of the wine industry began in earnest. Notable among these efforts were expansions in Washington, Oregon, Virginia, Michigan, Ohio, Idaho, Texas, Missouri, Arkansas and Pennsylvania. But other states have joined in this effort, too, such as Minnesota, Kentucky, Tennessee, North Carolina, Illinois, Iowa, and Nebraska, which is now boasting close to 15 wineries, and over 300 acres of primarily hybrid wine grapes.
Success in breeding efforts also depends upon the acquisition, testing and manipulation of new germplasm from domestic and overseas sources (Alleweldt et al., 1990; Eibach, 1989; Eibach et al., 1994; Reisch, 1993, 1994, 1995; Reisch and Pratt, 1996; Reisch et al., 1991; Fregoni, 1990; Bavaresco, 1990). Breeding programs have utilized native species, while access to foreign non-global cultivars has been very limited. New disease resistant materials have been developed overseas and should be tested for their potential in the Eastern US.
Continued success of the wine industry depends on access to well-adapted premium wine grape cultivars and suitable vineyard management and vinification techniques. Research programs must focus more heavily on selection and use the most promising V. vinifera and premium hybrid cultivars through extended testing. Enologists have introduced important modifications to vinification of established and experimental wine grape cultivars. These techniques can enhance desired wine flavors and color. Techniques such as temperature control during fermentation, heat processing of must and wine, selected wine yeast and malolactic bacteria, use of yeast nutrients, skin contact options for white and red cultivars, and blending of wines have been tested for experimental winemaking (Henick-Kling and Edinger, 1995; Pool et al., 1995).
In order to help protect domestic plant materials from contamination by foreign disease and pests, the USDA Plant Quarantine Law was enacted on September 17, 1912. It restricted the importation of foreign plant materials, and required a permit for anyone wishing to import them. During the ensuing years, import permits could be obtained fairly easily by anyone with legitimate reasons for wishing to import plant materials.
In 1948, the Foreign Quarantine Notices encoded as Part 319.37 of the USDA Plant Quarantine regulations "ended uncontrolled importation of clonal plant materials" and prohibited "importation or entry into the United States of any Vitis spp., excepting under special conditions or with a Departmental Permit issued by USDA". "Quarantine 37", as it came to be known, not only specifically mentioned Vitis spp, but also mandated a post-entry quarantine period for grapevines, conducted under the direction of a permit-holding plant pathologist.
Under these quarantine regulations, prohibited materials including grapes could enter the United States for experimental or scientific purposes, but they could not be released until they were tested for viruses. In 1950, tests for grape viruses had not been developed and, as a result, the USDA-Animal and Plant Health Inspection Service (APHIS) quarantine greenhouses in Glenn Dale, Maryland, were filled to overflowing with rooted grape cuttings. (Goheen, 1986). During those years, many precious vines died while at the USDA facility due to the inadequate funds and staff available for this critical work (Olmo, 1951). These difficulties meant that a virtual embargo existed on the introduction of new grape selections.
As a result, a USDA post-entry grapevine quarantine facility was established on the Davis campus. Olmo's master plan called for "an isolation greenhouse near or on the Davis campus. All foreign and out-of-state introductions would be sent directly there for propagation and indexing for viruses"(Olmo, 1951).
Eventually, a USDA "Departmental" import permit (one of the classifications of permits which can be issued by USDA) was issued to Hewitt, as the supervising plant pathologist in charge of disease testing. The University's first grapevine quarantine greenhouse, built by Hewitt to USDA specifications, was established on the Davis campus in the early 1950's. From that time, until 1988, the majority of grape importation in the United States was conducted at UC Davis, although Oregon State University was able to import clonal material from Burgundy, France. This program ceased upon the retirement of the permit holder.
In June 1988, due to the loss of equipment, facilities, and manpower that came with Austin Goheen's retirement, FPMS stopped making commitments to import additional grape materials. From 1988 to 1993, no importation occurred at FPMS, which was forced to refer its potential clients to the two active North American quarantine facilities at that time, Geneva, New York, and Saanichton, British Columbia. As a result of the quarantine hiatus in California, illegal clonal importation activity hit an all-time high; much-needed screening and indexing processes were often bypassed in favor of quick, potentially dangerous illegal entry.
Industry, the University of California, and the USDA proposed that quarantine service work could best be provided by FPMS with an internally held importation permit. A proposal for the desired new facility was completed in 1990, to be jointly funded by USDA, the University, and private industry. The new facility was constructed in phases over the ensuing four years. In 1990, a quarantine screen house and clean stock greenhouse; in 1991, a primary quarantine greenhouse, indexing greenhouse, soil storage area and head house; in 1992, a lab/office and second screen house; and in 1993, a second indexing greenhouse, landscape irrigation, and all fixed equipment (Nelson-Kluk, 1992). Vine importation and quarantine activities resumed in 1993 at FPMS with the opening of the National Grapevine Importation and Clean Stock Facility.
Limited funding is available for importation and quarantine work for grapevines. In the case of FPMS, the University of California provides administrative guidance, a community of talented scientific cooperators, and infrastructure support. The federal government provided funding for the construction of current facilities. Neither California state funds nor federal funds are available for grape introduction. The grape program is supported entirely by industry through income from sale of plant material, from FPMS grape program user fees, and from grants made by industry groups benefiting from FPMS programs. Prices charged for propagating materials and custom services reflect the high cost of establishing, maintaining and documenting an elite collection of vines. This is in contrast to years past in which both the University of California and USDA were able to provide significant support to these programs (Golino, 1989).
One of the major efforts in grape importation of the 1990s in the United States has been the introduction of clones of the global grape cultivars. Although some clonal research has been conducted in the United States (Alley, 1977; Pool et al., 1995; Wolpert et al., 1995), little funding has been available. In addition, the focus of grape selection programs in the U.S. has been more focused on the elimination of virus than the discovery and evaluation of clones (Alley and Golino, 2002). This is in contrast to Europe where many regional clonal programs have received large inputs of national funding and decades of attention from researchers. Of special interest in the United States are clones developed in the programs of France (Anonymous, 1995; Bernard, 1995; Boidron, 1995; Leclair, 1995), Germany (Schmid et al, 1995) , and Italy (Mannini, 1995; Paoletti, 1995; Bandinelli et al, 1995) where most of the major international cultivars have been carefully researched.
Given the importance and different needs of grape production in the various states it is not surprising that there are two National Clonal Germplasm Repositories (NCGR), one in Geneva, NY and the other in Davis, CA, and two USDA grape breeders (Geneva, NY and Fresno, CA). Additional USDA scientists at both Geneva and Davis are also involved in studies of grapevine genetics. In addition to these national efforts there are public grape breeding and genetics programs at the University of California, Davis; Cornell University, Geneva; the University of Minnesota; the University of Arkansas, Fayetteville; and Florida Agricultural and Mechanical University, Tallahassee. Since the 1960s, other publicly supported grape breeding programs have been discontinued including those in: Florida, Illinois, Maryland, Missouri, North Carolina, and Virginia More than four private grape breeding programs emphasizing development of fresh market grapes operate in California. Several other private corporations are utilizing genetic engineering and other tissue culture approaches to develop improved grape cultivars. There are also numerous viticulture research programs across the country focused on germplasm evaluation, cultivation, and pest control.
In some states, a broad range of V. vinifera, inter-specific hybrids, and native grape cultivars are utilized (e.g. Virginia, New York, Arkansas, Michigan). In other states, most of the grapes utilized are inter-specific hybrids. In Minnesota and other areas of extreme cold, vineyard expansion is based on grape cultivars from the U. of Minnesota program and from cultivars bred by private breeder, Elmer Swenson of Wisconsin. These cultivars are planted in significant quantities in Nebraska, Iowa, Illinois, Quebec, Canada and the northern New England states. In Missouri, Chardonel (from the Geneva, NY program) is now planted to nearly 200 acres and ranks as the top cultivar in terms of acreage, accounting for 20% of the area planted to grapes. More than 95% of the acreage in Missouri is planted to hybrid and native cultivars. In the Puget Sound appellation of Washington, a mixture of global and obscure V. vinifera, and inter-specific hybrid cultivars are grown to meet the needs of that cool climate region.
Prominent among the new cultivars introduced in recent years, in addition to Chardonel with its acreage increasing in Missouri, Arkansas, and Michigan, are the following:
Frontenac - very winter hardy wine grape from Minnesota.
St. Croix - winter hardy red wine grape from Wisconsin
Traminette - cold hardy and disease resistant grape making wine similar to Gewurztraminer; being planted rapidly in New York and elsewhere
GR7 - productive, cold-hardy blending red wine grape released by Cornell University-Geneva for use in 2003
The expansion of wine grape growing in numerous states has led to increased demand on the few breeders in the eastern states for material to test broadly across the region. States such as Illinois, Indiana, Virginia, Missouri, Arkansas and Michigan cooperate strongly with the Cornell University-Geneva and other programs to acquire promising wine grape selections for trial purposes. Each of the cooperating viticulturists conduct trials designed to suit their own needs and fit their own budgets. Much more could be learned through coordinated and uniform testing procedures.
The high value of grape plant materials, the competitive nature of the grape nursery business, and rapid globalization of the grape and wine community have resulted in some fundamental changes in the availability of grape selections, cultivars, and clones. The last few years have seen an increase worldwide in patented grape cultivars and rootstock selections, the introduction of trademarked clones of traditional cultivars, and the development of proprietary programs in which valuable selections are marketed exclusively and cannot be obtained by all growers. Some sales contracts for grape nursery stock even limit the rights of growers to subsequently propagate selections. Few governments today are willing to fund public programs for importation, certification, and distribution of grape stock, making the few remaining programs increasingly international in influence (Wolf, 1998).
The technology involved in both grapevine identification and plant disease detection has changed radically in the last ten years; resulting in rapid changes in grapevine quarantine, clean stock, and certification programs. In addition to these technical developments, changes in international trade rules may have important long-term implications for U.S. grape growers.
A search of the CRIS database was done and the summary is attached. Forty-four projects related to the objectives of this proposed project were found. The work is being done in 18 states as well as one Canadian province (Nova Scotia). This shows the breadth and depth of interest in this subject are.
Evaluate the viticulture characteristics and wine quality potential of clones of economically significant cultivars throughout the USA.
Characterize the viticultural and wine quality potential of emerging cultivars based on regional needs.
Conduct explorations within and outside of the USA for new or lesser known cultivars that may have economic potential for the US wine industry.
MethodsBecause of the range of climates, soils, and markets included in this project, specific protocols will require broad input from the cooperating experts and the statistician. This proposal only suggests the procedures which will be used to finalize vineyard and cellar protocols. The Guidance Committee will select cultivars for testing in this program. It will solicit suggestions from the wine industry and from technical experts. Examples of cultivars to be included are clones or cultivars with a documented history of production and value in wine production. Additional clones or cultivars may be included because they possess characteristics that may be of value to the industry. Cultivars and clones of potential economic value will be selected and grouped based on interest and need for various states and regions. Although not every item will be tested in every site, all items will be tested over a range of sites so that genotypic influences may be distinguished from environmental influence. All vines will be propagated from a single source. Vitis vinifera cultivars shall be grafted to a standard rootstock that is adapted to the site in question. In most cases 3309, 101-14, or Freedom rootstock will be suitable. Where phylloxera is not endemic, non-grafted vines will be included for comparison. Required number of vines and replicates will be based on committee expertise with advice of the project's statistician. Vineyard establishment and management will be based on Best Management Practices (BMP) for the production area where the trial is being conducted. The goal will be to produce disease free, ripe fruit for evaluation. A Work Team responsible for evaluating a particular cultivar will develop uniform protocols for planting and data collection. Weather and environmental data identified by the Guidance Committee will be collected at each site. Standard viticultural measurements will be collected each year at each site. Examples are: cane pruning weight, nodes retained at pruning, shoots per vine, shoot length, shoot weight, leaf area, yield per vine, clusters per vine, cluster morphology, berry weight, pest predation and disease status and cold hardiness. Vine phenology will be recorded. Berry sampling will be used to determine harvest date. After harvest, fruit sub-samples will be analyzed for juice soluble solids, pH, total acidity, color and organic acids (tartaric, malic, acetic). The guidance committee will specify the full compliment of components to be measured and the methods to be used. Wines will be produced with standard protocols developed by the guidance committee. Sufficient wine will be produced so that wines from different regions can be evaluated at several locations, and so that examples may be presented to stakeholders. Standard wine analyses, such as pH, TA, residual sugar, color, free/total SO2, malic, lactic, tartaric, and acetic acids, will be performed. The guidance committee will specify the exact components and methods to be used. Sensory analysis will be conducted regionally. Wines from each site will be evaluated at each testing center. Tasting methodology, wine descriptors, evaluator training and testing will be specified by the guidance committee. Sufficient wine will be produced so that presentations can be made to stakeholders in the various production regions. An expert in sensory analysis will be invited to join the technical committee.
Measurement of Progress and Results
- Wine grape growers would be provided with a greater diversity of grape cultivars suitable for a wide range of U.S. vineyard environments.
- Performance data would be available for clones of major and emerging wine grape cultivars indicating which produce quality wine and which are well adapted to various environments
- Information would be available through a database identifying cultivar and clonal characteristics and regional options.
- Standard evaluation protocols would be created appropriate for future evaluation in diverse regions and for multiple end products.
Outcomes or Projected Impacts
- Grapevine nurseries, grape growers, and vintners would be more competitive both within their region or production area and in the international market.
- The environmental impact of wine grape production would be reduced by identifying disease and pest resistant cultivars and cultivars.
- Alternative cultivar/product options would be created for areas where traditional cultivars and markets have declined.
- Our national grape importation program would be enhanced by evaluation data that would improve our ability to judge the potential impact of introducing individual accessions.
- Grape breeding and selection programs would be more efficient due to a better understanding of grape and wine genotype X environmental interactions and nature of clonal variation.