Rootstocks

The use of grape rootstocks in British Columbia has come about as a result of literature claims for influences that assist earlier fruit maturity; adaptability of some rootstocks to particular soil types; increased vine hardiness due to vigour control; and the introduction of grape phylloxera.

Selection of a rootstock for grape producers in British Columbia is not a simple matter. Grapes are not native to our province and we do not have a long history of traditional wine grape production. Our grape rootstalk research is limited but on going.

The first planting in the interior employed the use of 5BB, S04, 5C, and C-3309. There have not been any scientific studies in the valley showing comparisons of these rootstocks. However, there seem to be few, if any, reasons for complaints. Experience in the valley so far suggests that Riparia gloire, 3309, 101- 14, and S04 are suitable for the Interior. Each rootstock should be used with a full understanding of the soil it will be planted on and the irrigation management that will be used. Selection for the coastal areas requires some consideration of soil acidity and whether or not irrigation is used, as well as rootstock influence on fruit maturity.

Grape rootstocks were first developed in Europe to protect vineyards from grape phylloxera. Compatibility between rootstock and scion, plus ease of rooting, were also considerations. The North American species Vitis rupestris met these conditions. Plant breeders also needed a species that would adapt to the limestone soils found in many European vineyards. The North American species Vitis berlandieri was found to be the most useful, even though it is difficult to root. Today there are many rootstocks with various combinations of species. This range of rootstocks available presents possibilities to address many vineyard problems.

Climate and soils in British Columbia vary widely even within small parcels of land. There is no such thing as a single rootstock to serve all situations. Selection of more than one rootstock for a vineyard is therefore reasonable. Vigor control, for example, may best be achieved by selecting rootstocks which increase vigor on very sandy or gravelly areas, while rootstocks which reduce vigour are selected for areas with rich soils.

Understanding the parents for most rootstocks of concern to British Columbia grape growers is a basic requirement to understanding the characteristics of grape rootstocks. Fortunately, such understanding requires knowledge of only three species.

 

Vitis Rupestris

This is a species whose native soils are gravels and banks of mountain streams. It has a strong vertical root system. It is somewhat drought resistant. Rupestris, like Vitis berlandieri has a long vegetative cycle and matures late. It is tolerant to some lime conditions. Because of its long vegetative cycle, crosses of Vitis rupestris and Vitis berlandieri are best suited to warm climates with long growing seasons.

Vitis Riparia

Riparia is found in Eastern Canada and ranges as far as Mexico. It is found on river banks, islands or upland ravines. It is fond of water, but does not grow in swamps. It likes rich soils, but not lime. It is more tolerant of lime than Rupestris. Riparia has a short vegetative cycle and ripens early. It has excellent cold resistance. It has low vigour. Riparia X berlandieri crosses are quite vigourous, although they are less so than berlandieri X riparia crosses. Riparia Gloire de Montpellier is the only commercial pure riparia rootstock used today. It has low vigour and ripens its fruit and wood early. Crosses of Vitis riparia X Vitis rupestris include C-3309, C-3306, 101-14 mgt, Gravesac and Schwarzmann.

Vitis Berlandieri

V. berlandieri is native to the limestone hills of western Texas and neighbouring parts of Mexico. It is a cold and drought resistant species. It has hard, deep penetrating roots that branch little. V. berlandieri is long lived and phylloxera resistant. The vines of berlandieri bud out late and its fruit ripens late. There are no pure rootstock selections of V. berlandieri. It is very difficult to root from cuttings. Vitis berlandieri X Vitis riparia crosses include 5BB, S04, 5C, C-191-49, 420 A and 34 EM. Vitis berlandieri X Vitis rupestris crosses include 99 R, 110 R, 1103 P, 140 RU, and 1447 P

Some of the characteristics to look for in a grape rootstock:

 

Rootstock Characteristics

The listing in Table 3.2 of grape rootstocks and their characteristics is not intended to be all inclusive. However, Table 3.2 will point out what is known about the adaptive features of many rootstocks. Only a few of the rootstocks listed in Table 3.2 are actually used in British Columbia. Rootstocks used in BC include Riparia Gloire, SO4, 5BB, 5C, 101- 14Mgt. and 3309C. Producers should use care in selecting rootstocks so that specific concerns for their vineyard are addressed. In 1927, A.I. Perold said in a treatise on Viticulture that the highest fruit quality could be achieved only if the best cultivars scions were grafted to moderately vigorous rootstocks, then cultivated in a manner to limit crop size.

  1. Tolerance to phylloxera: All soils with 3% clay or more are potential sites for phylloxera. Soils with 7% or more clay will support the growth of phylloxera populations.
  2. Tolerance to nematodes:
    • Root-knot nematodes (Meloidogyne sp.) cause abnormal swellings on grape roots, which resemble swellings caused by phylloxera. On young roots phylloxera galls are hook-shaped, while nematode galls appear as an enlargement of the whole root. Root knot nematodes are more common in sandy soils.
    • Root-lesion nematodes (Pratylenchus sp.). These do not produce swellings. High numbers simply cause roots to deteriorate.
    • Dagger nematodes (Xiphanema sp.). Xiphanema bricolensis is the most common dagger nematode found in BC.
    A quarantine exists to prevent entry into BC of Xiphanema index, a virus transmitting nematode.
  3. Adaptation to calcarious soils: Most soils in the Okanagan have a pH of 6.0 to 7.5. Some have pH values well above 8.0. Most labrusca and hybrid vines will develop yellow leaves (chlorosis) and will have reduced berry set as a result of high pH soils. Vitis vinifera, in addition to being more drought resistant than the labrusca species, is also more lime tolerant. However, in areas where soil pH exceeds 7.9 (this is the point at which free lime begins to accumulate in soils), it is wise to consider rootstocks that are better adapted to soils high in lime content
  4. Adaptation to acid soils: Vitis riparia and Vitis labrusca are more tolerant of acid soil conditions (pH 5 to 6). Toxicities of aluminum and magnesium to grapes are common in soils with pH values of less than 5.5. The rootstocks Castel 196-17,101-14 Mgt., C-3309, 5C, 5BB and S04 are better adapted to well drained acid soils. A new rootstock, Gravesac, released from Dijon, France, is said to be suitable to cool climate areas and acid soils.
  5. Resistance to drought: Vitas vinifera on its own roots is quite drought tolerant. However when grafted onto another rootstock the drought tolerance changes. Tolerance to drought does not mean high production or high vigour if vines are placed under stress due to a lack of water. Rootstocks with a drought tolerant characteristic are usually able to “find” water in deeper soil regions or “store” water in its tissue due to a rapid thickening of root tissue. Crosses of V. berbandieri and V. rupestris are more drought tolerant than crosses of V. rupestrisX V. riparia or V. berbandieri X V. riparia.
  6. Vigour: Different rootstocks do not all absorb water and nutrients in the same quantity or the same proportions. Grafted vines therefore vary in vigour and production. Compatibility between vine and rootstocks also vary.

 

Table 3.2 Characteristics of Important Grape Rootstocks

Rootstock

Scion Vigour

Resistance to*: Phylloxera

Resistance to*: Drought

CrownGall

Phytophthora

Acid Soil

Water Logging

Riparia Gloire 2 5 1     2  
SO4 3 4 1 2 1 2 3
5BB 3 4 1 2      
5C 3 4 1 4      
101-14 mgt 2 4 3 5 2 1 4
420 A 4 4 2   1   2
1130 P 3 4 3 2 1 2 3
3309 C 2 4 2 4 1 2 3
*5-very resistant; 1-very susceptible, scion vigour - 1-low vigour, 5-high vigour

 

Characteristics of Important Grape Rootstocks

Rootstock

Tolerance for: Free Lime (%)

Tolerance for: Salt (g/litre)

Vigour*

Effect on maturityc

Dry, Shallow, Wet soil

Adaptability tob Deep Silt or dense clay

Adaptability toDeep, Dry loam

Sandy Soil

Riparia Gloire 6 0.7 2 + 3 1 2 2
SO4 17 0.6 3 + 3 1 2 1
5BB 20   3 + 3 2 2 1
5C 17   2 +   3 3 1
101-14 Mgt 9   2 + 3 2 2 1
420 A 20   2 + 2 3 2 2
1130 P 17 0.6 3 - 3 3 3 3
3309 C 11 0.4 2 + 3 2 2 2

 

a) 4-high; 1-low

b) 4-good; 1-poor

c) + advance; -delay

  1. Importing Grapevines

    Canada has specific grapevine import regulations that help to protect grape growers from the introduction and spread of virus diseases and other pests which are not yet established in British Columbia. Selected grapevine varieties/clones and rootstocks from Canadian-approved nurseries in France and Germany are currently approved for importation into Canada. Grapes may also be imported from approved sources in the United States. Note that the requirements for importation from France and Germany were changed in December 2005 due to the increased prevalence of flavescence dorée in France. Contact the Canadian Food Inspection Agency (CFIA) for more information on importing grapevines. Information on obtaining import permits may also be found at: http://www.inspection.gc.ca/ english/plaveg/importe.shtml.