Abstract:
Winegrape growing is extremely dependent upon site-specific variables.
To better understand the effect of rootstock-scion interaction in a cool climate
region, an experimental vineyard was planted in 1997 at the Oregon State
University Woodhall III property in the southern Willamette Valley.
The first experiment consists of Pinot noir (clone FPMS 2A) grafted to 19
rootstocks and an own-rooted control. Two years of growth responses and one
year's harvest data were analyzed. Rootstocks affected shoot length and shoot
diameter, leaf gas exchange rates, leaf chlorophyll contents, cluster size and
yield components, soluble solids, pH and titratable acidity. Treatments with long,
thick shoots and heavy pruning weights tended to have high chlorophyll contents,
with two exceptions. The Pinot noir own-rooted control and Riparia Gloire-Pinot
noir vines had elevated chlorophyll levels but shorter shoots and had smaller shoot diameters. Pinot noir grafted to 1103 Paulsen, 99 Richter, 110 Richter and
140 Ruggeri set fewer berries per cluster. 1103 Paulsen, 99 Richter, 110 Richter
rootstocks effected scion fruitfulness by lowering cluster weights. 125AA Kober
and 1103 Paulsen had the lowest levels of soluble solids but the highest pruning
weights, indicating a lack of fruit-to-canopy balance. Establishment rate was
highest for ungrafted Pinot noir vines and Pinot noir on 3309 Couderc, 4453
Malegue, 8B Teleki, Selection Oppenheim 4, 161-49 Couderc, and 420A
Millardet et de Grasset and the slowest for 110 Richter, 99 Richter, and 1103
Paulsen.
The second experiment consists of a 4 x 9 factorial trial. Four V. vinifera
scions on 9 rootstocks were planted and, as in the first experiment, physiological
responses and harvest data were analyzed. Responses of the interactions of
rootstock-scion were analyzed and affinity of scion to rootstock was observed.
Pinot noir grafted to 110 Richter showed low leaf chlorophyll contents.
Rootstock-scion interactions were observed in shoot length and diameter. V.
riparia x V. berlandieri crosses grew longer shoots of larger diameter. 3309
Couderc, Riparia Gloire and 4453 Malegue yielded smaller vines regardless of
scion choice. The counts of berries per cluster were different among treatments.
Affinity of scion to rootstock effected soluble solid content, pH and TA of musts,
although further study into vineyard maturation is needed.
