Thirty five vineyard blocks of Pinot noir were sampled at harvest by taking a two hundred cluster sample in 1993. Commercial wines from these blocks were analyzed by HPLC at two and nine months of age. Cluster weights ranged from 72 to 148 g, berry weights from 0.55 to 0.90...
Wines, specifically those in which lactic acid bacteria can grow can cause transient toxic effects due to the formation of biogenic amines such as histamine and tyramine. Some people specifically avoid red wines because they are more often associated with headaches and other discomforts. An understanding of the origin, occurrence...
Wines, specifically those in which lactic acid bacteria can grow can cause transient toxic effects due to the formation of biogenic amines such as histamine and tyramine. Some people specifically avoid red wines because they are more often associated with headaches and other discomforts. An understanding of the origin, occurrence...
Oregon grape growers are sometimes troubled with fruit set problems. There are many types of fruit set disorders, but a recently described one is inflorescence necrosis (IN). Though many studies related to the disorder have been done at OSU and elsewhere, investigation into IN is still in its infancy. Several...
The connection between the fruit-set disorder Inflorescence Necrosis (IN) and high ammonium (NI14+) in affected tissues has led to an investigation of NH4+ assimilation enzymes (principally glutamine synthetase (GS) and glutamate synthase) in grape tissues. Previous work in this department has suggested that toxic levels of NH4+ build up in...
Since phylloxera's discovery in a commercial vineyard in August of 1990, nine infestations have been verified in Oregon. With over 95% of Oregon's vineyards planted with ownrooted, Vitis vinifera, non-resistant vines, understanding the insect's biology under our conditions has become important for determining management strategies that minimize rate of spread....
A factorial design was used to vary leaf canopy structure of mature Pinot noir grapevines during two consecutive seasons: shoot tipping at full bloom (yes or no), lateral shoot length (no laterals, laterals cut back to 4 leaves at full bloom, laterals allowed to grow undisturbed) and cluster zone leaf...
RESEARCH OBJECTIVES:
1. Determine differences in microbial community structure and microbial biomass among Oregon vineyard soils using phospholipid fatty acid (PLFA) analysis.
2. Assess the relative importance of several environmental factors affecting microbial community structure in Oregon vineyard soils.
3. Test the ability of PLFA analysis to distinguish differences in...
The Chardonnay clonal trial was harvested on September 29th this year at the end of a week of unusually hot and dry weather. Most of the vines had been pruned to 20 nodes per vine but crop load was light due to small clusters. Yields ranged from less than 0.5...
Five replicated rootstock trials established in Oregon's three main viticultural. regions were evaluated for the effect of rootstock on Pinot noir performance. All the trials except Alpine included the following seven rootstocks: ungrafted Pinot noir, 3309 Couderc, 101-14 Millardet et De Grasset, 44-53 Mal6gue, 420 A Millardet et De Grasset,...