Rootstock 3309
French appellation
3309 COUDERC
Elements of ampelographic description
Identification involves:
at the end of the young branch which is closed, with a low to medium density of upright hairs and a zero density of downward lying hairs
young leaves that are reddish to tan
the branch has an erect and bushy habit, an elliptical to circular section, purplish in color, with a zero density of flat-lying and upright hairs
small to medium-sized adult leaves, orbicular, entire, involuted, with a U-shaped open petiolar sinus, sometimes limited by the vein near the petiolar point, or V-shaped on the leaves of the inter-hearts, a smooth, shiny blade, sometimes slightly waffled or hammered, with medium to strong anthocyanic pigmentation of the veins, and on the lower side, a zero density of flat-lying hairs and a low density of erect hairs
male flowers with anthocyanin pigmentation at the petal junction
with reddish-brown to purplish shoots, with no density of lying and standing hairs
Resistance to Soil Pests
3309 C has a very good degree of tolerance to root rot but is susceptible to the nematodes Meloidogyne arenaria and Meloidogyne incognita. It is said to have some degree of tolerance to Agrobacterium vitis.
Adaptation to the Environment
The degree of tolerance to chlorosis of 3309 C is low to medium and it resists only to 20% of total limestone, 11% of active limestone, and to an IPC of 10. On the other hand, it presents a good behavior in acid soils. 3309 C is sensitive to water stress, especially when it occurs suddenly during the vegetative cycle. On the other hand, its adaptation to humidity is good. 3309 C absorbs magnesium very easily and potassium more difficultly. This rootstock is extremely sensitive to chlorides and should be avoided when there is a risk of salinity. The 3309 C is well adapted to deep, sandy-clay, silty-clay soils, with little or no limestone.
Interactions with the graft and production objectives
The 3309 C has in general a very good affinity with the grafts. However, some blending problems have been reported with Cabernet-Sauvignon, Syrah and especially with Sauvignon Blanc. Clone 111 has been the most incriminated, without the causes being determined. More recently, compatibility problems with two Riesling clones have been observed. However, some of these varieties are grafted in significant quantities with 3309 C without any particular problem. The speed of development and fruiting conferred by 3309 C is a little slow. The vigor conferred is weak to average and the vegetative development obtained is balanced, in particular if the agronomic fertility of the soil is not too high. The 3309 C favors the setting of grape varieties sensitive to coulure. The products obtained with plants grafted on this rootstock are of recognized quality, and the blends made with Colombard, Gros Manseng, Petit Manseng and Tannat are particularly appreciated.
Ability to vegetatively propagate
The length of the internodes is weak to average and the diameter is average. The practice of green disbudding is recommended. The important growth of the prompts-buds and the lignification of the tendrils make the cuttings rather difficult. The wood production is low to average (20,000 to 50,000 m/ha), with sometimes a certain proportion of damaged wood. On the other hand, this rootstock presents excellent aptitudes as regards the recovery to the cutting and the grafting. Its wood is easily preserved. They require a good rehydration but hormoning is not essential and must be moderated if it is carried out.