Location: Horticultural Crops Research2012 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 areas where winter cold limits production and cultivation of well-known grape cultivars, like Merlot and Cabernet Sauvignon, cannot compete with established production regions. Lesser-known, Old World cultivars are commercially available in the United States, but their adaptation to non-traditional growing areas has not been evaluated. After four years of field evaluation, we have identified cold hardy, red and white cultivars from Portugal that produce ripe fruit at commercial levels of production and range in required days to maturity from 139 to 158. The survival rate of ten of the lesser-known cultivars was equal to or greater than the survival rate of 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 well-known cultivar standards. The estimated length of time for return on investment in a new vineyard planting is twelve years when vine establishment is successful, but can be much longer if the vines require replanting or additional labor for retraining after cold 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. This research was conducted in support of objective 305 1B Perennial Crops.