Table grape rootstocks in South Africa

RAMSEY

V. champini (a natural crossing) Synonym(s): Salt Creek

Origin: Discovered by T.V. Munson in USA, in 1900

GENERAL CHARACTERISTICS Tolerances relating to: Phylloxera: Very good according to local research. Nematodes: Excellent against root-knot nematodes; moderate against dagger nematodes. Phytophthora: Good. Crown gall: Poor. Wet soils: Good. Dry soils: Excellent (3) . Saline soils: Good Calcareous soils: Weak to good; depending on quantity of free lime present.

• Most planted rootstock for table grapes in South Africa. • Strong vigour and good to excellent quality grapes recorded with most scion cultivars on a variety of soils. CULTIVATION CHARACTERISTICS Compatibility: Moderate; results vary with omega bench grafting. Affinity: Problems especially with muscat flavoured cultivars, Crimson Seedless, Redglobe and various new cultivars. Rooting: May give poor results; the use of rooting hormones to overcome problems is recommended. Vigour if not grafted: Excellent (1) . Vigour if grafted: Excellent; scion can be developed fully during the season of planting. More canopy management is needed than with other rootstocks due to strong vigour. Petiole nutrient status tendencies: High N and P uptake; low Na and Ca uptake.

GENERAL: • Primarily used for its excellent tolerance against nematodes. • Induces strong vigour in scion cultivars.

• Results in good to excellent quality table grapes with most scion cultivars in a variety of soil types. • Sometimes results in fertility problems and poor colour development of red and black grapes when used in combination with inherently strong scion cultivars on fertile soils.

24 Table Grape Rootstocks in South Africa