Agriculture Reference
In-Depth Information
distinct varieties are identical. The risk is a
restructuring of the Italian (and not just Ital-
ian, of course) ampelographic platform that
rests on at times very sketchy data. In my opin-
ion, there is currently a real danger of what I
have defi ned as excessive revisionism of grape
history, an attitude that privileges concluding
that “this grape is not the grape you always
thought it was.”
of undergoing mutations, thereby developing a
slew of descendants that look and behave differ-
ently. In this sense, it's not that some varieties
are more prone to mutation than others, just
that they have been around longer. Pinot Nero
and Nebbiolo come to mind: it's not that these
two mutate more easily than others, as has
always been believed, but rather that they are
very old grape varieties.
Based on microsatellite analysis, Pinot Nero,
Pinot Grigio, and Pinot Bianco have the same
genetic profi le, but all look obviously different:
one has dark blue berries, another red-pink ber-
ries, and one white (actually yellow-green) ber-
ries. Yet microsatellite testing tells us they are.
It 's much more dif fi cult to distinguish between,
for example, Italy's many Verde-something
varieties or between Cataratto Bianco Lucido,
Cataratto Bianco Extralucido, and Cataratto
Bianco Comune, because the morphologic dif-
ferences present are a great deal more obscure,
and limited mainly to differences in berry
appearance. According to DNA microsatellite
studies, all three are genetically identical: but
in my experience, the
Cataratto
s not only look
and exhibit viticultural behaviors that are dif-
ferent enough, but the wines are different too.
The world of Italian grapes is fi lled with many
“different yet not so different-looking” grapes.
Diffi culties often arise because many completely
different grapes are given the same name, such
as the countless Montanaras, Montaneras, and
others still. Pigato, Favorita, and Vermentino are
another case in point. Pigato grows in Liguria,
Vermentino in both Liguria and Sardinia, and
Favorita in Piedmont. The three grapes have
been deemed genetically identical based on DNA
microsatellite results (as the three
Pinot
s have),
but the vast majority of Ligurian producers
(especially) refute this notion—and let me tell
you, quite vociferously at times. In fact, you can't
blame them, since there are obvious physical dif-
ferences between the three grapes, but appar-
ently their morphological differences are not
considered sufficient to separate the three
varieties as distinct. However, I am not so sure
there are only minor consequences for the
WHEN IS IDENTICAL REALLY IDENTICAL?
Besides excessive revisionism, excessive reduc-
tionism (“These two, or three, or four, etc.,
grape varieties are all the same”) is another
potential problem. It is why some modern
counts of Italy's native grapes list fewer than
four hundred varieties, and why many local
grape scientists believe that number to be
much too low. As we have seen, genetic profi l-
ing involves analysis of DNA sequence repeats
that scientist have always believed are not tran-
scripted (copied) and transcribed (translated),
or in other words, are not coded for anything.
In fact, scientists are becoming increasingly
aware that even the sequences of DNA that we
once thought did not code for anything are in
fact a lot more active than originally believed.
Hence, even those portions of DNA that micro-
satellite testing uses to determine identity
between varieties are not in fact quite as identi-
cal as we like to think they are.
One of the most interesting aspects in all of
wine is the existence of biotypes or subvarieties
(others use these two terms interchangeably
with
clones,
but this is incorrect), meaning
those varieties that are supposedly genetically
“identical” but have obvious morphologic and
physiological differences. Biotypes are mem-
bers of a grape variety that exhibit phenotypic
plasticity, by spreading out geographically and
adapting to different environments over the
centuries (see chapter 2). In so doing, they have
built up mutations. These mutations, depend-
ing on where they affect the genome, may or
may not have important consequences; clearly,
the older the variety is, the more chances it has
