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MC version of 'Viking' showed changes for all the color parameters (L,
A and B) and had also less erect petioles and more blistered leaves than
the 'Viking' original version. 'Viking' differs from the others varieties by
the fact that it did not change for any phenological trait while all other
varieties showed changes for at least one of those traits. 'Viking Matador'
showed changes for two traits: MC version had longer leaves and was
earlier than original version for one bolting index.
Based on the ascending hierarchical classifi cation (AHC), we classi-
fi ed all the versions of all the varieties considering all the traits observed
(except bolting and fl owering indexes) (Figure 5). We can draw two obser-
vations from Figure 5. If we separate the tree into six groups, each group
comprises the different versions of a single variety except two groups that
contain one version of 'Alwaro' each (and thus there is no 'Alwaro' group).
If we separate the tree into two groups, the two versions of 'Alwaro' are
still in different groups, in contrast to the different versions of all the other
varieties, which are always in the same group. The varieties appear to
have changed but conserved their phenotypic identity, except 'Alwaro,'
which seems to have signifi cantly diverged from its original version. AHC
confi rms the fi eld observations and the results of individual trait analysis:
'Alwaro' is the variety that shows the most phenotypic changes. Accord-
ing to the AHC, the 'Alwaro' original version is close to 'Supergreen' and
'Alwaro' MC is close to 'Viking Matador'.
From these two fi rst analyses (Table 5 and Figure 5), we observed that
all the varieties tested showed changes for at least one trait, but they con-
served their variety identity (the different versions of each variety were al-
ways grouped in the AHC). 'Alwaro' is a particular case as it has changed
signifi cantly for morphological and development aspects and it may be
appropriate to consider it two different varieties at this point in time. For
such a short period of time (two years), we were not expecting many phe-
notypic changes, and expected phenological criteria to change more often
than morphological traits. However, the traits used as varietal descriptors
often showed signifi cant changes and this surprised us. We next discuss
different explanatory factors that could contribute to the observed changes.
The choice of the experimental method was based on the method of
DUS testing, but we also wanted to detect fi ne changes, for which the
DUS method is not adapted. This is why we chose to observe one rep-
