Grézot 1
Name of vine variety in France (and common name)
Grézot 1 (G 1)
Breeder and year of obtention
Victor Grézot, 1894
Genetic origin
Based on genetic analyses carried out in Montpellier, this variety results from a 1202 Couderc seedling (Vitis rupestris - Vitis vinifera cv. Mourvèdre).
Evolution of areas under rootstock nurseries
1945 1965 1975 1985 2015
Rank 33 18 20 22 31
ha 0.4 12 17 3 0
Estimated surface area of French vineyards grafted with this rootstock and the main areas of use
10 ha.
Ampelographic description
The identification is based on:
- the tip of the young shoot that is half open with no or a very low density of prostate hairs,
- the slightly bronzed young leaves are slightly bronze,
- the shoots with no erect and prostate hairs,
- the involute kidney-shaped adult leaves, with an open petiole sinus, teeth with one side slightly convex and one side slightly concave,
- the female flowers,
- the very small, round-shaped berries, with a blue black skin.
Genetic profile
Allel 1 135 250 239 236 188 256 236 241 237
Allel 2 149 265 249 262 191 262 262 243 237
Resistance to soil parasites
G 1 is moderately resistant to phylloxera. This root-stock must therefore be plated under unfavorable conditions for this pest.
Adapt to environment
G 1 is susceptible to chlorosis and only resists up to 6% of "active" limestone. It is also susceptible to drought. This rootstock absorbs easily magnesium and is not very sensitive to magnesium deficiency. However, it absorbs potassium with difficulty in the soil. G 1 is also susceptible to chlorides and its use must be avoided if there is a risk of salinity.
Interaction with grafts and production objectives
G 1 generally shows a good affinity to grafts and provides a moderate to high vigor. This rootstock works well with Chasselas.
Aptitudes for plant propagation
This rootstock wood production is low to moderate (25 000 to 40 000 m/ha) but it has a good cutting and grafting capacities.
Resistance to aerial parasites
G 1 is moderately tolerant to the gall form of phylloxera and shows a good resistance to downy mildew.
Clonal selection in France
In France, there is no certified clone for this variety yet.