The Canadian grape and wine industry is challenged with growing grapes under variable climates and climatic extremes
The grape and wine industry plays a large role for the economy of Canada with respect to agriculture and agritourism. Canada’s grape and wine industry contributes $11 Billion into the Canadian economy each year and sustains a workforce of about 45,000 full-time equivalent employees (Economic Forensics and Analytics Inc., 2019a).
Ontario, Canada’s largest wine-producing province, accounts for approximately $5.5 Billion of this economic impact and represents 22,000 full-time equivalent jobs (Economic Forensics and Analytics Inc., 2019b). The Niagara Peninsula located in the province of Ontario is the largest grape production area with roughly 13,500 acres (5,463 hectares) under vine.
Freeze injury can result in significant economic losses
Cold tolerance is the most limiting factor in grape production. Freeze injury is the greatest threat to wine grape production in Canada where significant crop loss can occur from a single cold weather event. Erratic climate conditions in winter can impair the cold acclimation of grapevines and result in substantial damage and economic loss.
Research indicates that even cold hardy varieties can lose cold tolerance significantly as winter progresses and particularly after the onset of warm temperatures above freezing. Increased cold tolerance, resistance to temperature fluctuations and loss of hardiness due to deacclimation and reducing early bud break would reduce the susceptibility of grapevines to freeze injury particularly in challenging seasons or erratic weather situations (i.e., abnormally warm weather followed by extreme cold).
Research to better understand grapevine hardiness acquisition and to develop practices for hardiness improvement, freeze protection and cold damage mitigation are critical to develop innovative strategies to combat crop and quality losses due to weather and the threat of climate change. Hardiness improvements even by a degree or two could be a significant improvement for cold tender or frost susceptible cultivars. Improvements in cold tolerance through cultural practices, a practical spray application of a plant growth regulator or the use more cold tolerant grapevines would be of tremendous benefit to the grape and wine sector.
Freeze injury mitigation
Currently there are few tools for improving winter survival for cold-tender varieties other than the use of wind machines during frost or freeze events. Regional cold hardiness research from across Canada’s viticulture regions provide critical information on grapevine responses from different genotypes within varying climate or terroirs. These data can be integrated into existing cold hardiness monitoring and warning programs such as VineAlert to alert growers when cold mitigation practices are required. Improved hardiness response modelling will also enhance real-time precision hardiness management in vineyards.
Optimising cold hardiness through vine material selection
Through a decade of hardiness testing of Vitis cultivars, we discovered relationships between hardiness and overwintering success of cultivars but also inter-cultivar differences. Over the past 8 years, we have discovered that grapevine clones, rootstocks and their interactions can differ with respect to their cold tolerance and that they can vary during acclimation, maximum hardiness and reacclimation.
Therefore, our lab has focused more attention to cultivar x clone x rootstocks as an adaptation strategy to mitigate climate change. We have established large cultivar x clone x rootstock evaluation trials in Ontario in partnership with industry and through a federally funded Agriculture and Agri-Food Canada Agri-Science cluster grant. This work is expanding with additional collaborations across Canada.
Through this research, Canada will have a domestic clean vine program with vine material that is optimal for Canadian and cool climate conditions. This program may also lead to clone and rootstock selection programs within Canada. The contributions from this research will significantly improve the sustainability of the Canadian grape and wine industry and other cool climate regions.
Plant growth regulators to improve cold hardiness
Plant hormones such as abscisic acid (ABA) applications to grapevines can improve cold hardiness, maintain dormancy and delay bud break. Our initial research shows that synthetic ABA analog application may be a novel and practical way to improve cold hardiness in grapevines without negatively impacting fruit composition or quality. ABA analogs may prove very beneficial in optimising cold hardiness in grapevines. Furthermore, ABA application may also delay deacclimation which could result in less freeze damage associated with sporadic warming and freezing events during dormancy.
Freeze mitigation strategies
As viticulture and plantings of cold tender V. vinifera have expanded in Canada, there has been a need to have adequate freeze protection strategies to avoid catastrophic losses. Therefore, our lab group has studied new ways to improve overwintering of tender grapevine material.
One area of plant protection in vineyards that previously was not reported in literature was the use of geotextile fabrics. These materials are used in many different applications including mining and construction industries however studies for overwintering woody plants in agriculture were not well known.
Through our research, we have determined that geotextile fabrics can successfully be used to overwinter V. vinifera cultivars in regions where temperatures fall well below their critical lethal temperatures during winter months. Adoption of this technology is starting in all growing regions across Ontario and Canada because of this research and technology transfer and now existing and new operations are starting to use geotextiles to overwinter tender grapevines.
About CCOVI
The Cool Climate Oenology and Viticulture Institute (CCOVI) was established in 1996 at Brock University located in the heart of the Niagara Peninsula in Ontario, Canada. It is a partnership between Brock University, the Grape Growers of Ontario, the Wine Council of Ontario and the Winery and Grower Alliance of Ontario. CCOVI is an internationally recognised research institute dedicated to the advancement of the Ontario and Canadian grape and wine industry.
Brock University is building a state-of-the-art research farm where scientists are coming together to help transform Canada’s agriculture ecosystem into a self-reliant, sustainable model for the world. Cutting-edge research and innovation will create solutions to help mitigate the effects of climate change and sustain production of world class wines as we move into a new world of weather.
A series of quarterly updates will provide readers research topics and initiatives that discuss innovation in the grape and wine sector.
References
Economic Forensics and Analytics Inc. (2019a). Canada’s Wine Economy—Growth and Innovation Through Global Challenges. Wine Growers Canada.
Economic Forensics and Analytics Inc. (2019b). Ontario’s Wine Economy—Growth and Innovation Through Global Challenges. Wine Growers Ontario.
