There are many factors to consider when selecting a rootstock for vine production. Danie van Schalkwyk has the following suggestions to aid your decision.
Soil is the main factor that influences rootstock selection because the anatomical and physiological attributes of rootstocks differ in their adaptability to and utilisation of different soil conditions.
Before any recommendation can be done, trenches of about 1.2 m should be dug to determine the soil type, soil layers and any restrictions, such as:
- Layers of clay and sand and the depth at which they occur
- Compaction and the depth at which it occurs
- Large rocks and the percentage of stones present
- Any free water that may be present at the bottom of the hole
Soil samples should also be taken to determine the salinity and nutrient content of the soil, as well as the percentage sand and clay that is present. Knowing these conditions will significantly help to narrow down the choice of rootstock.
But there are many other factors that should also be considered such as:
- Resistance to soil borne pests and diseases
- Lime and salt
- Water-retention capacity
- Rootstock vigour
- Adaptability of rootstock to the specific soil and climate conditions,
- Availability of rootstocks
- Cost of different scion to rootstock-graft combinations.
- Rootstocks will also influence the vigour of the vines and the time of ripening.
Table 1 lists some of the most popular rootstocks available in South Africa and their suitability to different conditions.
In South Africa (SA), there are many rootstock cultivars that may be legally grafted or planted in terms of legislation, but only a few of these are used commercially.
Richter 99 – Recommended on relatively deep soils (60 cm to 90 cm) with good drainage and moisture-holding capacity. Suitable for red and yellow soils without structure (Hutton, Clovelly), dark-coloured soil (Oakleaf), as well as scaly and granite soils (Glenrosa, Swartland, Sterkspruit) without drainage problems. It is sensitive to standing water and can be overly vigorous on deep fertile soils.
Richter 110 – The same as for Richter 99, but it is also suited to dry, medium-deep soils (40 cm to 60 cm). It is suitable for higher potential soils, which could induce overly vigorous growth.
101-14 Mgt – Performs well on a wider range of soils than Richter 99 and Richter 110. Can be planted on scaly and granite, structured soils (Glenrosa, Swartland, Sterkspruit) and shallow, wet soils (Cartef, Estcourt, Kroonstad and Westleigh). It induces earlier ripening.
Paulsen 1103 – Is recommended on relatively deep soil (60 cm to 90 cm) with good drainage and moisture-retention characteristics. It is adaptable to heavy clay-loam soils with a wet lower soil layer.
Ramsey (Salt creek) – This rootstock is mostly used for table grapes. It is recommended on relatively deep, sandy soils under irrigation (Fernwood, Lamotte, Longlands), especially where nematodes are a problem. Because of its excessive vigour it is not recommended on deep, fertile soils. It may induce poor berry set and fertility as well as later ripening.
143B Mgt – Is well adapted to heavy, wet, pot-clay soils with poor drainage (Sterkspruit, Estcort, Valsrivier). It is rarely used for wine grapes, but performs excellently with raisin grapes.
Ruggeri 140 – Because of its excellent drought resistance it is mainly used for dryland vineyards. It can be planted on a wide range of soil types, from deep soil (60 cm to 90 cm), soil with a good drainage (Hutton, Clovelly, Oakleaf), to shallow scaly and granite soils. Because of its vigour it is not recommended on deep fertile soils.
SO4 – This rootstock is suitable for limy soils. Because of its poor resistance to drought conditions it is not recommended for sandy soils under dryland conditions. It has the tendency to induce earlier ripening and ensures good berry set.
USVIT 8-7 – Is recommended for variable soils within close proximity of each other.
COMPATIBILITY & AFFINITY
When deciding on a graft combination, the compatibility and long-term affinity of the graft combination should be considered (see Table 2). Certain scion varieties don’t have good compatibility with rootstocks, such as, 101-14 Mgt, 143B Mgt and Ramsey.
- Grafted vines should be ordered a year in advance, before the end of March.
- Never buy second-grade vines, only purchase certified, grafted vines from a nursery that is registered with an industry body like the Vine Improvement Association in SA.
- The bunches of grafted vines should have a label issued by the relevant industry association.
- This indicates that the rootstock and scion material are the correct variety and clone, and originate from virus-free, tested foundation vineyards.
Did you know?
Up until 1886, grapevines in South Africa were planted on own roots (called ‘makstok’). Many of the vines started to die because of root lice, phylloxera (Daktulospharia vitivoliae). Many grape farmers went bankrupt in spite of government’s efforts to help them. Europe overcame the problem of phylloxera in wine grapes by grafting the scion cultivars onto wild American rootstock material.
South Africa tried without success to import plant shoots of resistant rootstocks from France. As an alternative, a great number of seeds from wild Vitis ssp. were imported from North America.
A number of South African rootstock cultivars originated from these seeds, such as Constantia Metallica, Schabort 1 and 2, De Waal Bostock, Donkie-Rupestris and Mooikelder.
Initially, promising results were achieved by grafting wine grapes on these rootstocks, but in 1920 the condition of many vineyards started to decline at an early stage once again due to poor affinity with some of the rootstocks.
Rootstocks with better affinity were imported to solve this problem. The best results were achieved with Jacquez and 101-14 Mgt. Richter 99 and 110; and 143B Mgt were imported during the 1930s.
Nematodes became a serious problem and Ramsey (Salt Creek), Dog Ridge and Fairy were imported from California, North America.
The Nietvoorbij Institute for Viticulture and Oenology also imported other rootstock cultivars with resistant attributes from France, Italy, Israel, Germany and Algeria (Paulsen, SO4, 140 Ruggeri, 44-53 Malegue, Castels, Vivet and Grezot.).
In 1949 Professor Chris Orffer from the University of Stellenbosch began to breed hybrids and selected a few promising hybrids, of which USVIT 8-7 is the most popular.
Never plant vines on own roots. Only use certified grafted vines.
- This article was written by Danie van Schalkwyk from the SA Agricultural Research Council Infruitec-Nietvoorbij and first appeared in Farming SA.