Established in 2004, the NE1020 (and currently NE1720) projects have been critically important with the objective of evaluation of new and emerging grapevine cultivars (and advanced breeding selections) through a period of extensive growth in vineyards and wineries in the United States. The adoption of regionally adapted wine grape varieties has enabled the production of wine in most U.S. states in the 21^st century. Grape production was limited to most non-traditional regions due to climate constraints on Vitis vinifera, the European winegrape species that is not suitable to most areas in the U.S. The development of new interspecific hybrids and the testing of rootstocks, cultivars, and clones has expanded wine production.

Winegrape cultivar selection is among the most important components of vineyard and viticulture industry management. Selection of suitable cultivars with cold hardiness and disease resistance, in addition to response to edaphic and climate conditions, is necessary to inform best practices for industry stakeholders [1-4]. Grape breeding programs, clonal selection, and the identification of regionally appropriate materials from germplasm collections and similar global production regions are sources for new cultivars for evaluation. Many of the grape cultivars grown in the emerging regions are only decades old and may not reflect the consumer or market demand, thus creating an impetus for improved grape cultivars for economic success and sustainability. This is especially true in response to climate change, which includes the management of abiotic stress, new and invasive insect pests, and disease. As new winegrape industries experience continued growth, and subsequently the economic impact that comes with it, the winegrape industries are dependent on improving quality and quantity of grapes and wine produced. Continued discovery, development, and evaluation of grape cultivars and clones is critical for maintaining growth within this emerging agricultural sector.

The NE1020 project was structured for coordinated plantings and data collection. The current NE1720 project has focused on a flexible design, allowing researchers opportunities to evaluate materials locally alongside sentinel varieties for direct feedback to state and regional stakeholder audiences. We are writing to renew the NE1720 multistate project for an additional 5 years, with the goal of addressing present and anticipated needs of grape producers in the United States.

1. Needs Identified by Stakeholders

NE1720 (and prior NE1020) project members include research and extension faculty from institutions across the U.S. that regularly solicit stakeholder input for continued development of their programs. In this integrated industry, stakeholders include grape growers (farmers), winemakers, as well as tasting room and event managers. Consistent responses from stakeholders include support not only for continued cultivar development and evaluation, but also for developing best management practices to improve consistency, quantity, and quality of fruit from evaluated winegrape cultivars and clones. For sake of brevity, “cultivars” refers to newly released varieties from breeding programs, varieties introduced from other wine regions, advanced breeding selections (pre-commercial), and clones (bud sports, mutants, etc.) with improved characteristics. There is also a need to evaluate these cultivars across a wide range of environments. For example, in Colorado, intermittent extreme cold temperatures in the past ten years have repeatedly decimated V. vinifera cultivars and caused the industry to realize the need for better-adapted cultivars with improved cold hardiness. Recent major weather events such as polar vortices, rapid temperature swings, and early spring growing conditions with frost events have exacerbated the need to identify cold hardy cultivars in many regions. For cold-climate regions, there is a need for cultivars that mitigate high acidity to produce different wine styles, since the Vitis riparia-based cultivars presently grown in the region have very high titratable acidity that requires significant winemaking effort to reduce acidity [5-14]. In the Dakotas, Colorado, and northern Minnesota realizing survival under extreme low temperature conditions and sustained productivity is an issue.

A national industry survey conducted in 2017 by the National Grape Research Alliance identified stakeholder priorities for genetic improvement of grapevines. Key findings of this survey included the selection of quality, disease and insect resistant cultivars in order to improve vineyard practices for more sustainable production. In 2018, the American Vineyard Foundation, a national grape and wine industry-funded research organization, conducted a survey of the most important research needs for grape and wine producers. Plant material selection including clonal and cultivar selection was ranked third, with 25.1% of respondents ranking it within their top two goals [15]. However, the two higher-rated research areas, “production efficiency & profitability” and “disease & insect control”, were key objectives in NE1020/1720 as they address sustainability initiatives critical for stakeholder success.

Objectives

1. Comprehensive evaluation of grapevine cultivars and clones for viticultural, pest susceptibility and fruit and juice quality characteristics, including enological characteristics and local adaptation for sustainable production.


2. Conduct initial screening evaluations of promising emerging cultivars and advanced breeding lines (pre-commercial) to determine suitability for regional adaptation of viticulture and wine quality attributes.


3. Explore new germplasm resources including disease resistant cultivars being released in Europe, plant introductions including Asian accessions, and less-known cultivars that may have economic potential for the US grape industry.

2.  Importance of the Work and Consequences If It Is Not Done 

Testing of new cultivars is typically limited to a few areas. Coordinated, multi-state testing is needed to evaluate adaptation in a variety of environments. With changing climate and increased weather variability, cultivar adaptation, including physiological hardiness and robustness to changes in insect and disease pressure will be an increasing issue. This multi-state project will leverage substantial investments made in breeding programs and help evaluate genotype x environment interactions. Sustaining these efforts over several years is a requirement to fully evaluate fully grape cultivars over the life cycle of a typical vineyard and across multiple years of weather occurrences. This is especially important for inland ‘continental climate’ regions, which are more subject to extreme swings in temperature than more maritime-influenced climates. Interestingly, growers are often interested in new varieties due to the environmental plasticity of many modern hybrid grapes and potential economic benefits, despite a breeding program not being able to test multiple environments prior to variety release. This multi-state project aims to reduce this knowledge gap and reduce the risk of advancing varieties.  The NE1020/1720 projects facilitate the breeding timeline by providing descriptions of environmental response characteristics useful for the breeder and stakeholder. These experiments lead to the removal of underperforming selections from the advancement pipeline or help target specific growing regions.  Availability of grapes adapted to these continental climates has greatly increased interest in grape growing, as has growth of farm wineries in most of the U.S. However, planting a poorly-adapted cultivar in the wrong place is a costly mistake. Vineyard managers can face expensive replanting and retraining costs after cold injury. Cultivar selection in specialty crops, especially in grapes, focuses on vine health, yield, but also fruit quality and wine quality attributes.

Cold temperatures; short, cool growing seasons, and humidity that are conducive to disease development limits the production of traditional V. vinifera cultivars in most emerging winegrape regions, and novel cultivars may be more suitable even in regions where V. vinifera cultivars may thrive. Cultivar selection is the primary method for reducing losses from cold injury in vineyards, and the relatively new development of cold-hardy winegrape cultivars suitable for the eastern U.S. and other emerging regions is only beginning to be optimized. Members of the multi-state project routinely conduct cold hardiness, disease resistance and training studies providing the breeders feedback on advanced selections as well as moving our understanding of vine physiology.

Grape breeding programs in NY, MN, and AR, have successfully evaluated and released new cultivars [16-18]. A nascent, yet robust, breeding program in ND expands the northern range for winegrape production. Ongoing research on trait genetics is being adopted rapidly via marker-assisted selection to increase breeding precision in the New York, North Dakota, and Minnesota breeding programs (vitisgen2.org). Hatterman-Valenti, Reisch, and Clark are actively adopting genetic marker technology to facilitate the development of disease-resistant, cold hardy cultivars with high quality wine potential. Information generated through NE1020/1720 and this proposed product trials will feed back into those breeding programs to either field-validate genetic bases for cold hardiness, disease resistance, and other important traits. Private breeders have also been important in developing cold-climate grape cultivars which require evaluation across diverse regions and climates [19,20]. In addition, novel V. vinifera and other hybrid cultivars from Europe, in particular those developed for disease resistance, are candidates for evaluation in this program. The number of available selections for a vineyard manager to evaluate is daunting and could result in years of lost revenue unless public, long-term evaluation of cultivars is conducted to reduce evaluation time prior to commercial planting.

University and Agriculture Experiment Station (AES) researchers are uniquely and best suited to conduct this research. Among the participants in this project are numerous experienced researchers with land, staff, equipment, and facilities capable of conducting comprehensive and objective field research. The support of the AES received by each cooperator does not represent simply a plot of land on which to plant their vineyard. The support systems and expertise of University and AES researchers include statistical support, computing hardware and software, basic and field laboratories with modern equipment, field research stations with suitable land, equipment, technical staff, and faculty colleagues who may provide ad hoc support and review of projects. Research and intellectual properties protections in-place within the University and AES systems ensures that all parties including breeders, nurseries, growers, wineries, and researchers themselves will be adequately protected, and ensure that research is conducted in a thorough and objective manner.

3. Technical Feasibility

The NE1020/1720 project has developed a network of sustained collaboration of viticulture and enology specialists across multiple states since 2005. Presently, participants from 15 states have active plantings, and partners from several other states who do not have formal plantings contribute expertise to the project. The existing team has the expertise to plan new plantings, apply appropriate viticultural practices, and collect data to evaluate new cultivars and clones. Objectives from the initial phase of this project were intentionally limited so as to develop a trial with maximum applicability across multiple regions with robust statistical design. However, the limitations built into the original methodology, including establishment of a single NE1020 planting design implemented in 2008 on specific rootstocks, training systems, and management programs, was deemed too restrictive by several participants, who dropped out of the project as a result. In NE1720 researchers adopted a more flexible model, allowing for more rapid evaluation and testing and continued planting of new and reducing limitations on individual collaborators to conduct cultivar evaluations that do not fit into a single national model. Successful collaboration over past years provides the foundation for this new model and continued success. While the robust, multi-site evaluation of cultivars within specifically defined climatic regions has not been conducted to date due to unforeseen differences in data sets, loss of collaborators, and vine loss in certain regions due to weather or management-related events, several plantings have resulted in published cultivar comparisons that are establishing performance benchmarks in the literature. 

4. Advantages of a Multi-state Effort

 Multi-state efforts capitalize on university faculty expertise for cultivar and breeding line evaluation where infrastructure exists for grape management. Evaluating cultivars in multiple growing environments in a coordinated and collaborative fashion makes data collection, analysis, and reporting more efficient and useful. Coordinated effort shortens the time to evaluate cold-hardiness and environmental adaptations by having many locations experiencing diverse weather events. The shared professional comradery among NE1020/1720 participants has allowed programs in each state to optimize their effectiveness by identifying gaps in knowledge, infrastructure, and experience, and has facilitated collaborations that address those shortcomings within a particular institution or program. The current project has allowed sharing of winemaking expertise for processing grapes from several plantings (e.g., multiple states have contributed grapes to Cornell and MN winemaking projects conducted through related, leveraged SCRI projects; several states have “outsourced” differential thermal analysis for cold hardiness at other participating universities). This leverages the winemaking and other expertise in states that do not have University winemaking or other specialized facilities.

Project participants cover diverse disciplines and areas of expertise. Faculty associated with the project hold appointments across the land-grant spectrum including teaching, research, and extension, and most faculty hold split appointments among those foci. Expertise includes viticultural management, which is the most common thread among participants, but also: plant pathology and entomology; Integrated Pest Management systems; Clean Plant certification; enology; plant breeding; genetics; enology, plant physiology; biostatistics; and interdisciplinary plant science. A unique attribute to NE1720 was the addition of community college representation from KS.

Collaboration among participants in the NE1020/1720 project has provided an opportunity and tools for securing funding for four Multi-state SCRI projects, Hatch funds available from participating AESs, funds from private foundations, state block grant programs, etc. Other collaborations with team members include Specialty Crop Block Grant (Clark and Hatterman-Valenti), the Vitisgen projects (SCRI), among other pending or non-funded projects and collaborations.

5. Likely Impacts

Notable Impacts of the Current project:  

A key outcome of the current project (NE1720) has been local observation of plant response to extreme environments. The genotype x environment interactions that can be tested by a plant breeder are generally limited and the current project allows for multiple environments for testing. A “test winter” or other extreme weather event is increasingly uncommon (at any one site) but is much more likely to occur across the range of project participant plantings. Extreme weather events within the realm of “cold hardiness” include rapid and devastating temperature swings; extreme cold weather temperatures especially with polar vortex events in midwinter, and late spring frosts. Single weather events with major impacts at one site can inform varietal selection at multiple sites.  The NE region offers a range of USDA Hardiness zones (3-7) for testing grapevines and represents typical growing conditions for cool and cold climate grape growing in the eastern US.

Cold hardy cultivars now account for nearly 20 % of Colorado’s vineyard area compared to about 1 % ten years ago, and approximately one third of that area was planted with cultivars tested in NE1020/1720. Limited comprehensive production statistics are available for the current planting and economic impact of vineyards and wineries since 2017. However, anecdotal evidence supports continued growth of the industries with the addition of new wineries and expanded acreage throughout the participating states. A maturation of the market has become obvious with indicators such as transitions of business to new ownership, slower adaptation of new cultivars, and simultaneously demands for replacement cultivars for a 3^rd generation of varieties more suitable to consumer acceptance and production sustainability.

Expected Future Impacts:  

Under our new model, we expect to be able to screen and test more candidate cultivars over a shorter amount of time by conducting efficient evaluations, and by continual establishment of plantings over the course of the project. Continued release of new, 3^rd generation cultivars (e.g. Itasca, Verona, and Crimson Pearl released from cold-climate breeding programs in 2016 alone) and pre-release trialing of promising ones. Successful testing and education will result in more informed growers who make better planting decisions and suffer fewer losses from planting a poorly-adapted cultivar in the wrong site. Multi-state, interdisciplinary evaluation will allow for assessment of other attributes (e.g. insect, fungal disease, phytotoxicity of agrochemicals, unique juice characteristics) to maximize potential productivity and quality of this new germplasm. Under this project, we expect that wine industries in our regions will continue to grow, with an average increase in acreage in production and wine value during the project period.