FRENCH EVALUATION OF THE CG ROOTSTOCKS: HISTORY AND RESULTS

The INRA-Cornell University collaboration started 20 years ago, with the introduction of 18 Cornell-Geneva rootstock selections to France.
They were first evaluated over 8 years for their ability to propagate.
Then they were planted at 2 locations (INRA Angers and Ctifl Bergerac) within the framework of the experiment Network called level 1 and selected for their level of dwarfing, yield and fruit size.
The CG selections showed a variability in the ability to root but numerous selections had rooting percentage higher than 70%. Liners generally developed much side-branching but some genotypes are promising, including CG.11, CG.13 and CG.7. The CG selections had a scale of vigor from M.27 to MM.106. At the extreme levels of vigor, there is CG.707 which looks like MM.106 and CG.9 which is quite similar to M.27. In the Cepiland-PAJAM^®2 to X2765 (an INRA selection which is 20% less vigorous than Cepiland-PAJAM^®2) range of vigor, there are some interesting numbers, including CG.30A, CG.13, and CG.202, and also CG.11 and CG.41, whose horticultural traits are very good and similar.
In 1998, layers were given to Davodeau-Ligonniere nursery in order to begin propagation for the European market.
In 2001, an international trial was planted in 6 countries to see whether the French horticultural performance of the CGs extended to south and north European countries.
In 2003, CG.7, CG.11, CG.13, CG.30A and CG.202 were planted in the main French production regions within the framework of the INRA-Ctifl-Regional Stations Network called level 2. Results of all the French experiments will be discussed.

IX International Symposium on Integrating Canopy, Rootstock and Environmental Physiology in Orchard Systems

M.H. Simard, C. Cattanéo, S. Codarin, L. Roche, H.S. Aldwinckle

Malus × domestica, apple, vigor, production, propagation

https://doi.org/10.17660/ActaHortic.2011.903.32