Agriculture Reference
In-Depth Information
Maletic, Pejic, Rodriguez, and Antonacci
(2006a) also showed that Malvasia Istriana is
distinct from Malvasia di Sardegna (Malvasia di
Lipari) as the percentage of common alleles is
low (33.3 percent).
Malvasia Istriana looks strikingly different
from other
Malvasia
s grown in Italy, and the
wines made with it differ as well. Usually the
grape bunch is medium-sized, cylindrical, with
one very small wing, and sparse; its round ber-
ries have thin but resistant, yellow-green skin.
Of the clones available to producers (ISV 1, ISV
F6, VCR 4, VCR 113, VCR 114, VCR 115, ERSA
120, ERSA 121, ERSA 122, ERSA 123, and ISV-
VA 101) the most commonly used are VCR 4,
VCR 120, VCR 121, and VCR 115 (they offer the
best balance between vigor and aromatic per-
sonality), but many producers opt for massal
selections, the best known of which is called
“Mina.” That said, Malvasia Istriana grapes
have always looked quite different to me from
producer to producer. According to Gianfranco
Gallo, one of the best producers not just of
Friuli Venezia Giulia but of Italy, huge intrava-
rietal variability is characteristic of this specifi c
grape. “In Friuli Venezia Giulia we have differ-
ent biotypes of Malvasia Istriana, partly due to
genetic differences and partly as the result of
environmental and human selection pressures.
This is why some of these grapevines have
large, very compact bunches, with wings and
without, but there are some very loosely packed
biotypes too. What they all seem to have in
common is a very well-developed stalk and
rather large berries.” The existence of site-spe-
cifi c Malvasia Istriana biotypes alluded to by
Gallo has received scientifi c backing in a recent
study that evaluated the morphological and
genetic intra-varietal variability of Malvasia
Istriana (Meneghetti, Bavaresco, Calò, and Cos-
tacurta 2013). Thirty Malvasia Istriana geno-
types consisting of eight Italian clones and
twenty-two accessions grown in the Istrian
peninsula of Croatia were studied. Ampelo-
graphic characterizations of accessions were
performed using twenty Offi ce International
de la Vigne et du Vin (OIV) descriptors. These
and microsatellite analyses confi rmed that the
thirty genotypes were of Malvasia Istriana. The
morphological analyses performed using the
OIV ampelographic descriptors identifi ed the
Italian clones in accordance with their prove-
nance: the two clones of the ISV (Veneto), the
two clones of ERSA (FVG), and the four clones
of VCR (Veneto). Not surprisingly, the Italian
clones and Croatian accessions were easily dis-
tinguished by differing ampelographic charac-
teristics. In order to study the intravarietal
genetic variability of the thirty accessions,
AFLP, SAMPL, and M-AFLP molecular analy-
ses were also performed. Interestingly, results
showed that the Istrian accessions were geneti-
cally more similar to each other than the Italian
clones. However, the AFLP, SAMPL, and
M-AFLP analysis results did not show a com-
plete correlation with morphological observa-
tions. Furthermore, while the Croatian acces-
sions were easily separated into ten subgroups
in agreement with their geographic origins,
such differences were not observed for the
three Italian sub-groups. It appears these
molecular approaches allow the identifi cation
of different biotypes within the Istrian
Malva-
sia
cultivar group and the characterization of
accessions according to their geographic
origins.
Overall, Malvasia Istriana is hardy and very
resistant, though it's a little oidium sensitive. It
does remarkably well in the fl at, gravelly river-
bed plains of Friuli Venezia Giulia's Isonzo
River basin. Clay is a no-no, since the variety
does not appreciate excessively water-retentive
soils, a well-known property of clay. For this
reason, many also plant Malvasia Istriana in
the highest portions of hillside vineyards,
where water drainage is facilitated. Hardships
such as these help diminish the variety's natu-
ral vigor, an absolute necessity if high-quality
wines are the goal. Gallo also believes that the
best sites are those located on soils made of
strata of Dolomia alpine rock, formed during
the Wurm glaciation; these poor soils have
more than 30 percent bedrock and the soil is
never more than 150 centimeters deep. Giorgio
