GRAPEGROWING
(Table 1). This shows that the lateral crop
clusters did not inhibit primary clusters
from accumulating sugar post-véraison.
Some lateral crop clusters on vines
were retained for later sampling postharvest to observe the extent of ripening
within the season. There was not much
of an increase in ripening after harvest
of the primary crop, as total soluble solids reached only 17.2° Brix nearly three
weeks after harvest (Figure 2).
There may be several reasons that the
lateral crop may not be able to achieve
further ripeness, including reduced sink
strength, cooler weather, reduced sunlight and day length and leaf senescence,
which was already diverting resources to
storage organs (trunk and roots) rather
than to fruit.
opy development in western Oregon, the
vine expends the ample resources (water
or nutrients) on more shoot growth, lateral shoot development and lateral crop,
all of which require canopy management
and may divert resources away from the
primary clusters.
While lateral crop growth showed little effect on final ripening of the primary
clusters, it is often managed through
lateral removal and hedging to reduce
canopy density and increase sunlight
exposure for better vine photosynthetic
efficiency and fruit development.
Oregon vineyards currently require significant costs in canopy management, and
this research is helping define what cultural practices can help alter vigor, yield,
fruit quality and production costs. PWV
Summary
Data summarized herein was extracted
from several research studies funded by
the following agencies: Oregon Wine
Board, Northwest Center for Small Fruit
Research and the Oregon Agriculture
Research Foundation.
This research suggests that managing
vegetative growth and vigor, whether
it is through fertilization, irrigation or
vineyard floor management practices, is
important in altering the total fruitfulness of shoots and increasing or decreasing yield potential.
However, while high vegetative vigor
may result in adequate yield and can-
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