1. ROOTSTOCK CONSIDERATIONS... ...
Sanjun Gu
Kentucky State University

2. Phylloxera

3. Thomas Volney Munson
The French government : the French Legion of Honor Chevalier du Merite Agricole (1888)
Foundations of American Grape Culture (1909), the standard reference for grape culture in the United States.

4. Much of the world’s viticulture involves rootstocks (Robert 1976).
Scions are usually a Vitis vinifera cultivar.
Rootstocks are often North American species or their hybrids.
Harvesting grapes (1500BC)

5. Rootstocks, YES or NO? YES if do vinifera!
Phylloxera—soil-borne pest. Native to North America
And,
Immune: Muscadinia rotundifolia
Resistant: V. riparia, berlandieri, and rupestris
Susceptible: V. vinifera

6. SCION: The fruiting cultivar above.
ROOTSTOCK: The plant forming the root system of a grapevine to which a fruiting cultivar is grafted.
SCION: The fruiting cultivar above.
GRAFTING: The process to join the rootstock and scion together.
Grafting Union

7. The Genus Vitis Vitis (from vita=life)
About 60 species, mostly Northern Hemisphere, 70% North American
V. vinifera: European grape
V. aestivalis: Summer or Pigeon grape or bunch grape
V. labrusca: Fox grape
V. riparia: River bank grape
V. rotundifolia: Muscadine grape
V. amurensis: Amur grape (Manchuria)
V. rupestris

9. Still Rootstocks? If I do Hybrids or American……
You do NOT have to, but:
Other pest resistance: root nematodes.
Abiotic tolerance: lime, drought, salt, low temperatures, etc.
Vegetative growth.
Yield.
Fruit and Wine Quality.

10. Criteria for Choosing Rootstocks (Reynolds &Wardle, 2001)
Phylloxera resistance
Nematodes resistance
Adaptability to high pH soil
Adaptability to saline soil
Adaptability to low pH soil
Adaptability to wet/poor drainage soil
Adaptability to drought
***Pest and Soil***

11. Effects on pest and disease resistance
Phylloxera (Harmon and Elmer, 1952; Shaulis, 1969; Lider 1993; Mullins 1992.)
V. rotundifolia, V. riparia, berlandieri, and rupestris.
Riparia Glorie, Mgt, SO4, 5BB, St. George.
Nematodes (Harmoon, 1952; Cirami, 1984; Mullis 1992.)
V. champini, cinerea, longii.
Ramsey, Dog Ridge, Harmony, 1613 C, SO4. etc.
Pierce’s disease (Loomis, 1965.)
V. champini, V. rotundifolia x V. bourquiniana
Barnes, Dog Ridge, and B-45.

12. Effects on Abiotic Tolerance
Lime tolerance
Vitis berlandieri and vinifera. 41 B, 333 EM, Fercal.
Drought tolerance
Hybrids of Vitis berlandieri/rupesrtis. 110 R, 140 Ru, P and 99 R.
Salt tolerance
Vitis champini. Ramsey.

14. Rootstock Physiology: what do rootstocks do? Not so clear!
Direct effect
The root system: root anatomy and morphology, development and distribution—genetics x soil environment
Nutrition: mineral uptake
Hormones
Indirect effect

15. Effects on mineral nutrient and chloride accumulation
Use of rootstocks affects mineral ion uptake and distribution. Leaf K+ level was highest on stocks 53 M and SO4, and lowest on 140 R, 420 A. (Cook et al., 1964; Tanggolar et al., 1989; Fardossi et al., 1995, Brancadoro et al, 1995)
Cl- accumulation of grape ‘Cardinal’ and ‘Thompson Seedless’ scions varied with rootstocks significantly. Vines on and ‘Salt Creek’ roots accumulated extremely low chloride. (Bernstein et al. 1969)

16. Effect on cold hardiness: vinifera and hybrid cultivars
Canes of grafted ‘White Riesling’ and ‘Chardonnay’ are hardier than ungrafted vines. Rootstock 3309 (over 5BB and SO4) is most desirable in relation to winter survival. (Miller et al. 1988)
‘Cabernet Sauvignon’ and ‘Chardonnay’ showed less frost damage when grafted on 5BB and P1103 than on SO4 and 420A. (Palliotti et al., 1991)
Grafted ‘Seyval’ has better cold hardiness of buds than ungrafted proved to be the hardiest rootstock. (Striegler and Howell, 1991)

17. Effects on vigor
Pruning weight and growth rate have been used to express vine vigor.
Most selected, pest-resistant rootstocks increase vigor. (Elmer and Harmon, 1935, 1950, 1956; Vaile, Hedberg, 1980; Ferree, 1996; Wounderer, 1999; Lovicu, 1999)
In general, vigorous rootstocks produced more wood in the first growing season and increased circumference thereafter than those of weak rootstocks. (Elmer and Harmon, 1948)
The species V. champini, berlandieri, rupestris and their hybrids are most vigorous while V. riparia has the least vigor. St George, 99 R, 110 R, etc. are most vigorous. Riparia Gloire and are among the least. (Roriz, 1999)

18. Effects on bud break and dormancy
‘Riesling’ and ‘Chardonnay’ deacclimated earlier when grafted on 5BB than when on (Miller et al., 1988)
Buds of ‘Anab e Shahi’ broke later on their own roots and Dog Ridge. Rootstock Gulabi sharply shortened the bud dormancy (Prakash, 1990).
Tangolar (1989) found that grape buds burst early on rootstock 420 A and Reddy (1990) stated that rootstocks Gulabi and 1613 increased bud “fertility”.

20. Results|Cold hardiness
Rootstock
Winter
Number of buds from canes
Number of buds NOT from canes
Winter survival
(%)
110
1103
3309
420
St. George
Own-rooted
Gloire
2.2 ab
1.7 a
4.6 c
3.4 bc
1.1 a
2.3 ab
2.1 ab
4.5 b
3.6 ab
6.2 b
8.0 c
2.9 a
7.9 bc
2.8 a
64.6 abc
54.2 ab
37.5 a
72.9 bc
47.9 ab
87.5 c
Nemaha NE

21. Results|Vine Growth Budbreak (m/d) Pruning weight (g) Leaf area (cm2)
Rootstock
Budbreak (m/d)
Pruning weight (g)
Leaf area (cm2)
Shoot length (cm)
110
1103
3309
420
St. George
Own-rooted
Gloire
4/25 b
4/23 b
4/15 a
4/17 a
4/27 b
4/18 a
36.9
44.7
48.3
45.0
27.0
45.3
44.2
180.7
77.8
91.9
107. 7
81.0
89.3
93.4
42.4
35.9
43.6
59.2
40.5
38.3
45.1

22. Results|Budbreak ab bc a ab cd d ab

23. Effects on Endogenous ABA and GA4 (Dormant buds)

24. Effects on photosynthesis, carbohydrates and dry matter partitioning
Photosynthetic rate: ‘Muller Thurgau’ had high rate on K5BB and SO4 and low rate on R 140 (Candolfi et al. 1997; Koblet, 1997).
‘Riesling’ had higher rate when grafted on K5BB than on its own roots though the stomatal conductance were similar (During, 1994).
Cane Carbohydrate levels and the partitioning of dry matter were not affected by rootstocks (Tangolar, 1989; Williams and Smith, 1991).

25. Effects on Berries Maturity Berry size, growth rate, weight
Cluster size, berries/cluster
Sugar contents(glucose and frucose), organic acid (tartaric acid, malic acid, amino acids) and K+ content pH
Anthocyanin in skin

26. Effects on Yield
Yield was an important consideration in selection of rootstock (Harmon and Elmer, 1948, 1952; Shaulis, 1969.).
Most selected rootstocks increase the yield though the situation relies on scion/rootstock combinations. (Hedberg, 1980; Mullins 1992 ; Lider 1993; Kolbert, 1994; Ezzahouani, 1995; Ferree, 1996; Lovicu, )
Yields are not always positively correlated to vegetative growth (Cook and Lloyd ,1964 )

27. Effects on Wine Quality
Lower malic acid and higher tararic acid concentration if grafted; higher anthocyanin content if non-grafted. (Walker, 1998)
‘Chardonnay’ grafted on 5C had desirable wine characteristics– low pH, moderate acidity and good sugar level. (Ewart, 1993)
Rootstock SO4 performed better than 5BB, 5C, 41B, Fercal, EM333 and R 140. (Kaserer, 1997)

28. Other things to consider …
Cost for grafting: $ /ha, depends on do-it-yourself or purchasing;
Disease transmitted by grafting: virus;
Incompatibility;
The ungrafted vines last longer;
Special attention to the grafting union, esp. in cold regions;
Others you can name…

29. What should I do if my vines are un-grafted vinifera?
Removing them or replanting them on rootstocks. Phylloxera will get them sooner or later (in Kentucky!)
Plant rootstock rootlings adjacent to the vines; wait, graft the trunk
Inter-planting with 2-year old grafted vines; remove the own-rooted vines when the new planting starts fruiting.
If yield loss >10%, think replace the vines with grafted ones immediately.

30. How to indicate the vines are affected by phylloxera
How to indicate the vines are affected by phylloxera? Especially when you think your vineyard is “free” from phylloxera
Told by stunted growth, not so easy though
Do 2% of own-rooted vines: every 10th vine in every 5th row is own-rooted
Plant some un-grafted rootstocks or American species as indicators: watch for the galls (Vinifera, roots; rootstocks, leaves, for example, “Frantanac”)

31. Am I the one to graft? Yes, you can handle it! Bench grafting
Greenwood grafting
Cleft, notch grafting
Bark grafting
Side-whip, wedge grafting
Field budding…

32. Questions and Comments?
CONTACT:
Dr. Sanjun Gu
128 Atwood Research Facility
400 East Main Street
Kentucky State University
Frankfort, KY 40601
Phone:
Fax:
Coming soon! New KSU Viticulture Web……