Field trials of weed control research on several vegetable crops are reported in this summary. Unless otherwise indicated these trials were conducted at the Vegetable Crops Research Farm at Corvallis. Soil type at this location is a silty clay loam and all plots were sprinkler irrigated as needed to provide...
This year's late spring frost prompted a number of growers to call OSU with questions about the fruitfulness of secondary buds and about management alternatives for frost damaged vines. In response to this concern three experiments were established in Willamette Valley vineyards. At Chateau Benoit Vineyard ten vines of MollerThurgau...
Cannabis sativa L. is emerging as an economically important crop, particularly for its high levels of cannabinoid production. One of these cannabinoids, cannabigerolic acid (CBGA), is the precursor to many well-researched cannabinoids such as the psychotropic delta-9-trans-tetrahydrocannabinolic acid (Δ9-THCA i.e., THCA) and the medically relevant cannabidiolic acid (CBDA). CBGA has...
Thesis research focused on: 1) Water and fertilizer gradients
within the plant root zone, and effects of chemical and physical
gradients on Trichoderma harzianum populations. 2) Regulation of root
growth physically with permeable fabric containers and chemically with
copper compounds. 3) Effects of copper coatings for fabric containers
on Glomus...
Pollen development is an important process in male flower development, the timing of which may be correlated with time of pollen shed in hazelnut (Corylus avellana L.). Early to very late blooming cultivars were identified and the relationship of microsporogenesis and microgametogenesis, and time of pollen shed were studied in...
This study records the fifth consecutive year that winter losses of managed honey bee (Apis mellifera) colonies in the USA have been around 30%. In April 2011, a total of 5,441 US beekeepers (an estimated 11% of total US beekeepers) responded to a survey conducted by the Bee Informed Partnership....
Estimates of winter loss for managed honey bee (Apis mellifera) colonies are an important measure of honey bee health and productivity. We used data from 5,500 US beekeepers (5,244 backyard, 189 sideline and 67 commercial beekeepers) who responded to the April 2012 Bee Informed Partnership Winter Colony Loss Survey and...
This study was undertaken in a Red Delicious apple orchard in
Oregon's Hood River Valley to determine if low leaf P concentrations
were contributing to such observed, orchard disorders as poor shoot
growth, shoot dieback and. small fruit size at harvest.
Subsurface applications of lime and superphosphate had no
effect...
Eastern filbert blight (EFB) is a devastating disease of European hazelnut, Corylus avellana, which causes economic losses in Oregon, where 99% of the U.S. crop is produced. The causal fungus, Anisogramma anomala, is native to eastern North America, where it is found associated with the American hazelnut (C. americana). Although...
This investigation was undertaken to observe possible changes
in growth substances in Pyrus throughout the dormant period. The
primary objective was to determine if a correlation existed between
growth substance content and the inherent chilling requirement of
seeds and buds.
Samples of whole buds were taken at intervals from the...
Urban agriculture (UA) is defined as the production of food crops or livestock within urban areas. Despite its popularity in the United States, research into UA systems suffers from a general underrepresentation of commercial urban systems. As a result, urban growers often have unique technological needs that are unmet by...
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...
Background:
Abscisic acid (ABA) regulates various developmental processes and stress responses over both short (i.e. hours or days) and longer (i.e. months or seasons) time frames. To elucidate the transcriptional regulation of early responses of grapevine (Vitis vinifera) responding to ABA, different organs of grape (berries, shoot tips, leaves, roots...
Acclimatization of in vitro apples and plums was examined in
four studies: l) Leaf anatomy and water stress of aseptically cultured
'Pixy' plum grown under different environments, 2) Acclimatization
of aseptically cultured 'Mac 9' apples to low relative humidity,
3) Stomatal functioning of aseptically cultured 'Mac 9' apple
leaves in...
Contamination of newly planted bermudagrass (Cynodon spp.) varieties by undesirable off-type bermudagrass genotypes is an
ever increasing concern for turf managers because selective control options are limited. In 2009, a sethoxydim {2-[1-(ethoxyimino)butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one} tolerant bermudagrass genotype (93-175) was identified during
herbicide screening at the University of Georgia in Tifton. The objective...
The azalea lace bug (Stephanitis pyrioides Scott) is a global pest of rhododendrons and azaleas (Rhododendron spp.). It is originally from Asia, has been established in the eastern U.S. for the past century, and was recently detected in the Pacific Northwest in 2008-2009. Stephanitis pyrioides feeds on the underside of...
The closed insulated pallet system (CIPS) was evaluated for growth, yield, and
fruit quality of tomato genotypes with determinate growth habit. Plants were irrigated
with several levels of sodium chloride (NaCl) salinized water. Tomato growth and yield
were significantly greater in CIPS than in conventional surface-irrigated containers,
regardless of irrigation...
Orchard floor management (OFM) practices can improve soil function and alter
the soil biological community. Soil function is dependent on soil forming materials and
on management practices but little is known about how OFM affect orchard soil quality,
fertilizer N uptake, or tree growth and production.
Research plots were located...
Nonchemical weed control strategies are in short supply in snap beans, particularly strategies that target weeds within the seed row. Recent work demonstrated the limitations of propane flaming and organic herbicides for weed control in stale seedbeds. There was very little improvement in weed control with propane flame or organic...
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...
Three distinct stages of flower cluster abscission were identified
prior to fertilization: flowers which did not begin development (stage
1), flowers which had begun development (stage II) and clusters which
had begun to form distinct nuts (stage III). Abscission of stages I
and II coincided with a rapid increase in...
This study evaluates Beufil's Diagnosis and
Recommendation Integrated System (DRIS) on hazelnuts.
Although sufficiency ranges are currently the main
approach for fertilizer recommendations in Oregon, DRIS
enhanced nutritional interpretations, and might alter
recommendations. Reference values (DRIS norms) were
developed using 15 years of published and unpublished
field data. DRIS indices...