Location: Horticultural Crops Research2011 Annual Report
1a. Objectives (from AD-416)
The market for wine grapes is increasingly global. A large share of this global market is based upon a few specific cultivars that consumers know and associate with high quality, such as Cabernet Sauvignon, Merlot, Chardonnay, and Riesling. Production of these global cultivars has increased in pace with a recent increase in world production of grapes and, in some cases, has resulted in an oversupply. The recent market saturation of global cultivars has stimulated interest in exotic, new products (varietal wines) in order to expand or maintain markets. Global predominance of a few major cultivars is undesirable also for ecological reasons because it reduces the genetic diversity of wine grapes under commercial production and leaves the industry vulnerable to threat from a potentially lethal insect or pathogen. There is great potential for minor cultivars from old world production regions to produce wines in the U.S. that are superior to their place of origin and these cultivars may be well adapted to newly emerging grape production areas, such as the Snake River Valley in Idaho. Little information is currently available about the performance of lesser-known, exotic cultivars in wine grape growing regions of the U.S. Research is particularly needed on the performance of exotic cultivars under the limitations and advantages of growing conditions in the U.S. which are most likely unique from the conditions in their region of origin. Traditional methods of evaluating cultivar performance are costly because site-specific conditions influence results and limit their applicability to a narrow geographic range. The objectives of this project are to identify lesser-known wine grape cultivars from Portugal, Spain, Italy, Greece and France, that are well-adapted to the climatic features of the Snake River Valley American Viticultural Area; to integrate performance data from the Idaho field trial site; and to provide a graduate student with a training opportunity.
1b. Approach (from AD-416)
The adaptation of lesser-known cultivars to climatic conditions in the Snake River Valley will be accomplished by evaluating the viticultural performance of 18 lesser-known cultivars planted in a randomized, block design with six replications at a trial established in a commercial vineyard in Southwestern Idaho. A graduate student will be recruited through a cooperator at Boise State University who will collect, analyze and report viticultural performance data. The trial will be established and data will be collected following protocols established by the multi-state NE 1020 Coordinated Wine Grape Cultivar Evaluation project. Viticultural performance data will be interpreted relative to two “global” cultivars planted as reference standards in the Idaho site as well as trial locations in other states. The trial site in Idaho will estimate cultivar adaptation to high elevation desert. The proposed evaluation scheme enhances resource-efficiency because trial results will be applicable over a range of climatic conditions, providing useful information for existing as well as newly emerging wine grape production sites. Documents Trust with ID State Department of Agriculture. Log 41539.
3. Progress Report
Wine grape acreage in the United States has recently expanded into less traditional growing regions where well-known grape cultivars, like Merlot and Cabernet Sauvignon, may be less productive or of poor quality for competitive winemaking. There are many lesser-known cultivars from Europe that have recently become commercially available in the United States. These lesser-known cultivars may have great adaptation potential in the United States and could be particularly well-suited to newly emerging grape production areas in the United States. Evaluation of adaptation in wine grape requires multiple years because there is a three year delay from planting until the first commercial harvest and a five year delay until full production. Little is known about how these lesser-known wine grape cultivars survive cold or whether they can produce and ripen fruit under unique environmental growing conditions. Thirteen, lesser-known, red and white-skinned cultivars from Spain, Italy, France, Portugal, Greece and Germany were planted in 2007 alongside well-known cultivar standards Merlot and Cabernet Sauvignon in a replicated field trial located on a commercial vineyard. The vines in this study have completed three growing seasons. The survival rate of ten of the lesser-known cultivars was equal to or greater than the survival rate of the well-known cultivar standards. The poor vine establishment of three of the lesser-known cultivars was mainly due to cold injury during the winter. Seven lesser-known cultivars produced mature fruit of equal quantity and quality to the well-known cultivar standards. The estimated length of time for return on investment in new vineyard plantings is twelve years when vine establishment is successful, and longer if vines require replanting or additional labor for retraining after injury. The findings of this study are important because they identify novel planting material with high adaptation potential for climates considered marginal for wine grape production and therefore make an important contribution towards successful vineyard establishment.