Promising grape rootstocks
By Dr. Alireza Rahemi
By Dr. Alireza Rahemi
Ontario’s South Coast Wineries and Growers Association (OSCWGA), recently initiated a project to identify grape rootstocks resistant to Phylloxera and tolerant of severe winters, in an effort to improve the industry’s capacity in south central Ontario.
The project was undertaken at the University of Guelph’s Simcoe Research Station.
Phylloxera (Daktulosphaeria vitifoliae Fitch.), an endemic pest in eastern North America, is a small insect, similar to an aphid, that can feed on grapevine leaves and roots. Phylloxera feeding on roots can kill grapevines. A few Vitis riparia have been used as rootstock in Europe and North America. The rootstock is highly resistant to Phylloxera, and it has been used to improve winter survival. Also, it is native to southern Ontario and tolerates local weather and soil conditions. The development of rootstocks resistant to Phylloxera, while mitigating winter hardiness to scions, will help grape growers produce good quality grapes. The primary goal is to expand the industry in the sandy soils and severe winters in the south central region of Ontario.
The project has two goals: intermediate and long term. They include:
- testing known rootstocks, derived from V. riparia, with representative vinifera scion cultivars presently grown in the south central region of Ontario, and
- obtaining and selecting suitable V. riparia clones from southern Ontario that are able to balance plant vigor to sandy soils and be able to impart winter acclimation and adaptability in the scion cultivar.
Four scions – two for white wine (Chardonnay, Riesling) and two for red wine (Pinot Noir, Cabernet Franc) – were selected by Ontario’s South Coast Wineries and Growers Association. They were grafted onto four rootstocks, Gloire de’Montpellier (V. riparia), Couderc 161-49 (V. riparia × V. berlandier), Couderc 3309 (V. riparia Tomenteuse × V. rupestris Martin), and MGT 101-14 (V. riparia × V. rupestris). The selected potted vines were planted in six sites at intervals northwards in Ontario [Burning Kiln Winery (Turkey Point), Villa Nova Winery (Villa Nova), Bonnieheath Winery (Waterford), Golden Leaf Estate Winery (Langton), and Blueberry Hills Winery (St. Williams), and the sixth at the Simcoe Research Station of the University of Guelph] between June 6 and 18, 2013.
About 905 wild grape genotypes were collected from throughout southern Ontario (Norfolk, Brant, Oxford, Middlesex and Elgin, Kent, Haldimand, Prince Edward, Hastings, Frontenac and Grey counties). These were planted in three replicates at the Simcoe Research Station of the University of Guelph on May 17, 2013. We also planted 46 accessions from the Vineland collection and research vineyards (from France, Vermont, New York, New Jersey, Quebec, Minnesota, Manitoba, North Dakota, Montana, Illinois, Kansas, Colorado, Missouri, Wyoming, New Hampshire, Connecticut and Iowa). Most samples are V. riparia, but we also have some accessions from V. labrusca, V. aestivalis and V. rupestris.
The next step will be to evaluate the fruit quality and plant growth and survival rate of the clones and wild germplasm and to select the desired one for further investigation. The selected cultivars can be recommended to growers in this area. A grape cultivar needs to be grafted on the selected germplasm to study the behavior of the grafted plant and its fruit quality. The promising rootstocks will then be introduced to growers in this area.
Investment in this project has been provided by Agriculture and Agri-Food Canada through the Canadian Agricultural Adaptation Program (CAAP). In Ontario, the program is delivered by the Agricultural Adaptation Council.
Dr. Alireza Rahemi is a research associate with the department of plant agriculture at the University of Guelph.