Inflorescence necrosis (IN) is a recently described disorder in grapes
characterized by partial or complete deterioration of the pedicel and rachis near
bloom. Elevated levels of ammonium in the rachis are associated with the
incidence of IN and hypothesized as the cause of the disorder. An incubation
system with single-node...
Dormancy of 'Pinot Noir' grapevines was characterized. Primary buds
required ca 300 cumulative chilling hours (CCH) to initiate the transition from
endodormancy to ecodormancy, which occurred in mid November. Additional
chilling, up to 1000 CCH, improved budbreak. Changes in bud water content
were estimated by gravimetric and spectroscopic methods. Total,...
The effect of canopy orientation on fruiting performance of 'Beurre
d'Anjou' pears (Pyrus communis L.) and postharvest urea spray on ovule
longevity and fruit set of 'Doyenne du Comice' pears were studied.
Hedgerows of 'Beurre d'Anjou' pear trees planted in 1969 in two
orientations north-south (N-S) and east-west (E-W) were...
Several effects of xylem discontinuity in Pinot noir and Merlot grape berries were studied. There was a reduction in the amount of apoplastic dye (Eosin Y or azosulfamide) uptake through cut pedicels into soft versus firm berries, suggesting a reduction in maximal xylem flow at that time. Both greenhouse and...
There are several grape disorders that reduce fruit
set. One, millerandage, is from poor fertilization to
produce "hen and chicken" or small seedless berries; while
another, Coulure, is the failure of grape flowers to
develop into berries. A third one, inflorescence necrosis
(INec), is a disorder that should be in...
The use of grass cover crops is a recommended practice in
nonirrigated vineyards in the Willamette Valley, Oregon. Two
studies were initiated to investigate the competitive and
noncompetitive effects of grass cover crops on the growth and
development of Pinot noir grapevines. Two greenhouse pot culture
experiments were performed to...
In the Northwest, two tree fruit production problems may be
related to the role of ethylene on plant growth and development:
flowers and developing fruits are subject to low temperature injury
during early spring, and to the low fruit set of 'Comice'. Ethylene
may be involved in influencing dormancy and...