Almost all the wine varieties described in Wine Grape Varieties in California are of pure Vitis vinifera parentage. This species is particularly prone to attack by two root pests: grape phylloxera and parasitic nematodes. Vitis vinifera vines can be protected from these pests by grafting them to rootstock varieties derived from other vine species and resistant hybrids. Many of the rootstocks used for this purpose are adapted to particular soil types, chemistry, and fertility. They may also be used to overcome vineyard problems such as drought, excess water, and salinity.
It is important that growers select rootstocks that are:
- resistant to present and potential soil pests
- suitable for the soil’s texture, depth, and fertility
- compatible with soil chemistry (pH, salinity, lime content)
- favored for the anticipated soil water availability, drainage, and irrigation practice
- appropriate for the vineyard design, and
- appropriate for the fruiting variety’s growth and fruiting characteristics
In this blog, each wine variety’s description includes information on rootstock suitability and experience. This information is based on written reports throughout Europe and the New World, including California. The ratings and comments provided here are based on prevalence in the literature and those reports most likely to fit California conditions.
Riparia Gloire
Riparia Gloire was selected in Montpellier, France and is also known as Riparia Gloire de Montpellier. This rootstock was one of the first used after the phylloxera crisis in Europe, but does provide enough iron to its scions in limestone-based soils. It roots and grafts well, has strong phylloxera resistance, but is susceptible to some strains of root-knot nematodes. Riparia Gloire has a reputation for low vigor even in fertile sites, but little is known about the performance of this rootstock under current viticultural practices. It is likely to do well in high density plantings with ample water, and is reported to hasten maturity of scions grafted on it. Riparia Gloire has very large leaves with three lobes and sharp teeth. 1616C appears similar, but it has sharper teeth, a wider petiolar sinus and sparsely scattered hairs on the shoot tips.
Common synonyms: Gloire de Montpellier
Species: V. riparia
Country of origin: France
Breeder: Viala
Year released:
Pedigree: Vitis riparia
Berry color: None
Phylloxera Resistance : Hight
Nematode Resistance
Root Knot : Low
Dagger (Xiphinema index) : Medium
Tolerance
Drough : Low
Wet Soil : Low
Salinity : Medium
Lime : Low
Sélection Oppenheim 4 (SO 4)
Breeder and year of obtention in Sigmund Teleki and Heinrich Fuhr, 1896. This variety is derived from the crossbreeding of Vitis berlandieri and Vitis riparia derived from Euryale Rességuier. Identification signs include:
- the tips of the young shoot are half opened with a anthocyanin pigmentation collar and a moderate coat of flat-lying hairs,
- young leaves are bronze color,
- the shoots are elongated with a ribbed contour, a slightly elliptical section, the nodes and the internodes are shiny red with reddish spots on the underside and an absence of upright and flat-lying hairs,
- trifid tendrils,
- adult leaves are large, wedge-shaped, upturned with an ondulated leaf blade between the veiins, a U-shaped or open Vshaped petiolar sinus, teeth with straight sides, slight anthocyaning pigmentation of veins and the underside with a sparse to moderate coat of uprights hairs,
- male flowers,
- vine shoots are dark brown.
SO 4 resists up to 35% total limestone, 17% of active limestone with an CPI of 30. Its resistance to ferric chlorosis can be considered as moderate. It is well suited to acidic soils and its tolerance for chlorides is fair but it is not very adapted to humidity (low to medium tolerance). This rootstock sometimes appears susceptible to Dutch elm disease. Its resistance to drought is medium to good but its adaptation to humidity is low to medium. SO 4 resists up to 35% total limestone, 17% of active limestone with a CPI of 30. Its resistance to ferric chlorosis can be considered as moderate. It is well suited to acidic soils and its tolerance for chlorides is fair but it is not very adapted to humidity (low to medium tolerance). This root stock sometimes appears susceptible to Dutch elm disease.
Its resistance to drought is medium to good but its adaptation to humidity is low to medium. SO 4 doesn’t absorb magnesium very well and promotes the onset of black stem. This root stock is well suited to sandy soils (provided that the magnesium deficiency is corrected), valley terroirs and clay limestone soils which are moderately or not fertile. It however appears to be not well adapted to very dry terroirs, prone to chlorosis in addition to too compact soils.
Generally speaking, SO 4 is quite compatible with grafts but the trunk radial growth is very limited. It is said that this rootstock has a “thin leg” which may create substantial differences in diameter with grafts and the need for trellising. The growth speed for plants grafted SO 4 is substantial and the vigor transferred to the grafts by the root stock is high, particularly during the first part of the vine’s life cycle (the first 15 years). SO 4 produces high yields, starting from the first years after planting which sometimes requires thinning. Good sugar contents are produced but the wines obtained oftentimes lack body and sometimes have herbaceous notes due to its high yields. SO 4 likewise produces wines with high pH levels.
Phylloxera Resistance : Hight
Nematode Resistance
Root Knot : Medium to High
Dagger (Xiphinema index) : Low to Medium
Paulsen 1103
Paulsen 1103 was developed by Frederico Paulsen on the island of Sicily in 1895. Strangely enough it was only imported to South Africa in 1962. It is a cross of Vitis Berlandieri x Vitis rupestris and has similarly good grafting compatibility with most Vitis vinifera cultivars as is the case with Richter 99 and Richter 110. Only recently was it discovered that it completely fails when grafted to Red Globe (it was also found to be the case in Egypt).
Paulsen 1103 can be considered a rootstock somewhere between Richter 99 and Richter 110. It found very good application in the drier and warmer Mediterranean islands and countries like Spain, southern Italy, northern Africa and Greece. Paulsen 1103 has very good resistance to lime induced chlorosis, which is common in these regions, it has good drought resistance and adapts well to high summer temperatures. One can say it performs well in “harsher” Mediterranean climates which are very similar to that found in the Western Cape. One of the reasons why it did not find a foothold in South Africa, may be the fact that it did not offer many advantages over Richter 99 at the time of its introduction 30 years later.
aulsen 1103 is considered to have medium high to high vigour, somewhere in between Richter 99 and Richter 110. It performs well on similar soils as Richter 99, in other words shallow compacted and dry soils; it tolerates more sandy gravel topsoils than Richter 110 and has a deep, well-branched root system which gives it good drought tolerance. It does have one advantage over Richter 99 and that is that it can tolerate subsoil wetness, which Richter 99 cannot do. It has, however, one drawback in that it has low tolerance to Phytophthora cinnamomi. Its resistance to salinity is better than Richter 99, but less than Richter 110. The statement that Paulsen 1103 is somewhere between the two Richters makes a lot of sense. Paulsen 1103 is steadily increasing in popularity in both the table and wine industries. Paulsen 1103 gives much more balanced growth during the early season compared to Ramsey for naturally vigorous cultivars, aiding the process of bunch thinning during bloom. It also has a positive effect on colourat n for red and black cultivars. In some areas it replaced Richter 110 on the sites with higher soil potential due to the slightly better vigour it induces.
Paulsen 1103 has moderate to good resistance to root-knot nematodes, but offers only moderate resistance to dagger nematodes.
We do not have much experience of this rootstock in South Africa, but based on its characteristics and the little experience we do have, one can speculate as to its further potential for expansion. Paulsen 1103 will perform similar to Richter 110 for quality production on the red calcareous soils of Robertson/Ashton. It may even outperform it on the harder subsoil limestone layers overlain with sandier topsoils. It can also be used on the colluvium slopes of the coastal areas such as Durbanville and around Stellenbosch (higher slopes of sandstone gravel) where Richter 110 is not an option, as well as Elgin/Grabouw and the Hemel-en-Aarde Valley on the gravelly shales.
Paulsen 1103 definitely has a place in the South African grape industry, but it will not replace Richter 99 in the “drier” dry-land areas of the Agter-Paarl and Swartland with tougher Swartland and Klapmuts soil forms. In these areas Richter 99 does not have its equal in terms of drought tolerance. However, Paulsen 1103 can be an option on the deep red Hutton and Oakleaf soil forms as found on the hillside slopes around Malmesbury and Darling and under supplementary irrigation in the Coastal areas it can definitely replace Richter 99. Paulsen 1103 is a good alternative and growers do not have to be afraid of poor performance (drought tolerance) where supplementary irrigation is available, but under intensive irrigation sandy soils should be avoided due to a risk of nematodes. The continued introduction of new table grape varieties may see Paulsen 1103’s increased use, especially for coloured varieties.
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