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 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...
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...
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...
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...
Oregon Master Gardeners were surveyed to identify volunteer demographics, as well as familiarity with and frequency of use of current computer technology. The Oregon State University Master Gardener Program has evolved over the past 25 years, and as such so have the training needs. New demands are presently being made...
Temperate climates are particularly conducive to
growth of annual bluegrass which readily invades and
dominates most cool-season turfgrasses. Ethofumesate
(2-ethoxy-2,3-dihydro-3,3-dimethyl-5-benzofuranyl
methanesulfonate) is one herbicide available which will
selectively control annual bluegrass.
The primary objectives of this research were to
determine optimum application rates and timing of
ethofumesate for control of...
A study was conducted to characterize the vesicular-arbuscular
(VA) fungi of apples grown in Oregon. Using roots and soil from
apple orchards as inoculae, six different fungal species were found
in pot cultures: Gigaspora margarita Becker and Hall, Glomus fasciculatum
(Thaxter sensu Gerdemann) Gerd. and Trappe, Glomus mosseae
(Nicol. and...
Lime was applied at different rates to filbert trees grown in
containers in an acid soil. As lime application rate increased, the
leaf Mn and extractable soil Mn were significantly reduced. In
control trees leaf Mn was over 1300 ppm, but no growth reduction or
Mn toxicity symptoms were found....
Bacterial canker, caused by Pseudomonas syringae pv. syringae is
recognized as one of the greatest limiting factors in cherry production
in Oregon. Disease incidence may be decreased when susceptible
cultivars are high-grafted onto tolerant/resistant rootstocks. This
research was begun to develop a rapid screening method which could be
used to...
Farewell-to-spring (Clarkia amoena) is native to the Pacific Northwest and commonly found in gardens, due to its aesthetic value and purported benefits to pollinators. Oregon and Washington are home to five subspecies of C. amoena, yet commercially available seed is limited to C. amoena ssp. lindleyi and C. amoena cultivars....
School garden programs have become increasingly popular for their diverse, positive benefits. School gardens are often promoted as a relatively low cost means to offer hands-on learning opportunities that may foster academic achievement, particularly in the sciences, however only six studies have been published on the impact of garden education...
Grapevine red blotch disease (GRBD) is caused by Grapevine Red Blotch Virus, a virus in the Geminiviridae family. Observable symptoms can manifest in red cultivars, such as leaf blades that are partially to fully red, red veins, and different combinations of the two. Previous research has shown evidence of reduced...
Alcoholic off-flavor and accompanying volatile compounds produced by bananas (Cavendishii spp) held at 20°C and subjected to aerobic (air control treatment) or anaerobic conditions (nitrogen treatment) were compared by solid phase micro extraction (SPME), a newly developed method for volatile separation. In general, volatile production was suppressed under anaerobic conditions...
Crops were planted into tilled strips in an established perennial ryegrass
(Lolium perenne L. 'Manhattan II'), sod covering various portions (55%, 66%,
77%) of the row width. Italian beans (Phaseolus vulgaris L. 'Romano II')
biomass and yields showed a trend among sod strips with lower yields
produced in plots with...
The following taxonomic keys are adapted in part from the subgeneric and species descriptions and keys produced by McGinley (2003), Gibbs et al. (2013) and Gardner and Gibbs (2022). Additional identification information was provided by Jason Gibbs, Thilina Hettiarachchi (University of Manitoba), and Joel Gardner (Washington State University). While these...
Drosophila suzukii (Diptera: Drosophilidae), is a serious pest in soft and stone fruit industries worldwide. The unique serrated ovipositor of female Drosophila suzukii allowed the species to reproduce in intact, ripening fruit before the harvest. Current control methods rely heavily on insecticide application, only becoming less profitable due to the...
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....
Pacific flatheaded borer (PFB), Chrysobothris mali Horn (Coleoptera: Buprestidae), has recently become a serious pest in newly planted European hazelnut, Corylus avellana L. (Betulaceae) in Oregon. Larvae feeding on the inner bark can lead to girdling, loss of transpiration, and ultimately can cause dieback or death of the tree. Although...
Foliar B sprays have increased fruit set in 'Italian' prune
(Prunus domestica L.) by 2 fold in some trials and had no effect
in others. This work was conducted to identify reasons for this
inconsistent response. Since B levels in flowers are associated
with the amount of fruit set, factors...
Organic agriculture is an important and growing sector of U.S. and world food production. Consumers are increasingly aware of and interested in the production practices and impacts associated with agriculture and as such, are showing a preference for sustainably produced, raised, and harvested foods. In order to continue to meet...
Lilacs are a group of ornamental trees and shrubs in the Oleaceae family consisting of 22 to 30 species. There are six series within genus Syringa: Pubescentes, Villosae, Ligustrae, Ligustrina, Pinnatifoliae, and Syringa. Fertility and cross-compatibility among cultivars, species, and series have yet to be formally investigated. Over three years,...
Interspecific hybridization was initiated between wild P. acutifolius accession G40199 and P. vulgaris to introgress resistance to Acanthoscelides obtectus (bean seed weevil). F1 interspecific hybrids were recovered by embryo rescue and maintained until flowering. Mostly sterile hybrids were backcrossed twice to common bean cultivar ICA Pijao to recover sufficient fertility...
Although the concept of breeding crops for organic agricultural systems has been around for decades, few studies have been reported for vegetable crops to quantify and compare how conventional and organic systems differ in their selection pressures on genotypes advancing through the breeding cycle; especially research utilizing modern sequencing capabilities....
Improving crop cultivars for use on organic farms is pertinent, as current elite germplasm is less resilient within the more variable context of organic farm environments. Although a growing number of studies have focused on organic plant breeding in cereal crops, very few have focused on vegetable crops, especially those...
The purpose of this research was to develop tools and germplasm for the production of tomatoes (Solanum lycopersicum L.) with high fruit phenolics without the use of genetic engineering. A candidate gene analysis was undertaken to identify genes regulating anthocyanin biosynthesis in tomato fruit (Aft, Abg, atv, and Purple Smudge)....
Purple tomatoes (Lycopersicon esculemtum) were bred by incorporating
genes that result in anthocyanin production in the skin of fruits. These genes
originally came from related wild species as no naturally occurring genes encoding
fruit anthocyanin expression are known within the cultivated species. By
combining Aft or Abg with atv or...
The common cherrylaurel (Prunus laurocerasus) and Portuguese cherrylaurel (P. lusitanica) are economically important landscape shrubs across the United States. To gain a better understanding of physiology and morphology in these higher level polyploids (P. lusitanica, 2n = 8x; P. laurocerasus, 2n =22x), a variety of breeding experiments were performed. The...
Processors need broccoli with better quality traits than what is available in cultivars developed for California and Mexico fresh markets. Farmers need to reduce labor costs of broccoli production by mechanizing harvest. Most contemporary commercially available cultivars are not suitable for either mechanical harvest or processing. The objective of the...
Processors need broccoli with better quality traits than what is available in cultivars developed for California and Mexico fresh markets. Farmers need to reduce labor costs of broccoli production but mechanizing harvest. Most contemporary commercially available cultivars are not suitable for either mechanical harvest or processing. The objective of the...
Processors need broccoli with better quality traits than what is available in cultivars developed for California and Mexico fresh markets. Farmers need to reduce labor costs of broccoli production by mechanizing harvest. Most contemporary commercially available cultivars are not suitable for either mechanical harvest or processing. The objective of the...
Research efforts were focused on testing various inbred combinations for hybrid production and adaptation to Oregon growing conditions. Trials at the Vegetable Re-search Farm included a yield trial of OSU derived hybrids, and observation trials of OSU inbreds and hybrids. Breeding funds were used for a major portion of the...
Objectives:
1. Develop broccoli varieties adapted to western Oregon with suitable quality, high yields, and disease resistance. Specific traits include:
a. Early to midseason maturity
b. Concentrated yield potential
c. Head rot and downy mildew resistance
d. Large openly branched heads that are well exserted and have clean stems for...
With the hot summers of recent years causing significant heat damage to broccoli heads within the Willamette valley, varietal screenings for newer and more heat tolerant varieties became necessary. Most commercially available broccoli varieties are bred for production within milder and more climatically stable regions, such as the Salinas Valley...
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...
A series of four studies were conducted in Colombia, South America,
in the field and the greenhouse to determine the effect of plant
competition and mulching on carbohydrate and photosynthate distribution
and nitrogen fixation in beans (Phaseolus vulgaris L.).
Mulching beans (determinant growth habit) with rice hulls in the
lowland...
In Pisum, the Np gene conditions two mitotic responses - to bruchid weevil oviposition on the pod and to reduced UV light. Oviposition by the weevil results in tumorous or neoplastic growth under the egg. Biochemically active compounds, called bruchins, were isolated from two bruchid insects (Doss et al, 2000)....
Cereal residues suppress the development of small seeded, summer annual weeds. The focus of this study was to determine whether cereal residues can be used to suppress weeds in cucumber production systems in the Pacific Northwest. In the first of three experiments, cereal residues of fall-planted, spring-killed cover crops suppressed...
This investigation was undertaken to determine, from a dietetic
standpoint, the amounts and proportions of dextrose, levulose and
sucrose present in Bosc pears, and to furnish information that might
be of value in the development of by-products from the off-grade
fruit of this variety.
The attempt was made to carry...
Size and color are important visual quantity attributes of the fruit of strawberry (Fmgaria x ananassa Duch.). Strawberry cultivars produce fruit of a characteristic size and color, the later being the result of accumulation of particular anthocyanins. This research sought to determine the basis for genotypic differences in fruit size...
The innate ability of potato leaf tissue to initiate freezing
was studied. Two potato species, the non-hardy cultivated potato
Solanum tuberosum L. cv. Russet Burbank, and Solanum acaule Bitt. a
hardy species from South America, were studied. Two treatments,
low (cold) and high (warm) temperatures were included to study the...
Bacterial blight (Xanthomonas arboricola pv. corylina) (Xac) of hazelnut (Corylus avellana L.) was described first in Oregon in 1915 and is now recognized as a damaging disease of young hazelnut trees worldwide. Stressed hazelnut trees in conditions such as planting on marginal sites, and trees between 1 and 4-years-old are...
Genetic and morphological characteristics of an architectural mutant in common beans were studied. The mutant had shiny, dark green leaves, overlapping leaflets, short petioles and a reproductive terminal bud even though the line did not carry the fin gene. Branching was nearly absent resulting in a single stem vine. This...
An enzyme catalyzing the formation of
O-glucosylzeatin in immature embryos of P. lunatus was
purified 2500 fold using ammonium sulfate precipitation
followed by affinity and anion exchange chromatography.
The enzyme uses trans-zeatin as substrate (Km 28 uM) but
not cis-zeatin. ribosylzeatin, or dihydrozeatin. Both
UDP-glucose and UDP-xylose can serve as...
Twenty-one pairs of simple sequence repeat (SSR) primers were used to
investigate genetic diversity in 270 accessions of European hazelnut (Corylus avellana)
representing a wide geographic range. A capillary electrophoresis system and ABI
Genescan® and Genotyper® software were used to determine the allele size generated
from each PCR reaction based...
Geohumus is a new, unique hybrid soil amendment made of polyacrylic acid, igneous rock flour, and quartz sand. It is biodegradable and is marketed to increase soil porosity, increase plant yield, and increase plant available water by up to 30%, all while using a low inclusion rate of only 1...
White mold, caused by Sclerotinia sclerotiorum (Lib.) de Bary, results in severe losses in the production of common bean, Phaseolus vulgaris, especially snap bean varieties. Advanced backcross QTL analysis was used to identify quantitative trait loci for resistance to white mold in an interspecific cross of P. vulgaris and P....
Vertically shoot positioned (VSP) training systems are common in Oregon's Willamette Valley, where deep fertile soils and high regional precipitation task growers with curbing vegetative vigor within this system. Management strategies, such as canopy hedging and cluster-zone leaf removal, are used to improve microclimate within the canopy and around the...
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...
Hazelnuts (Corylus avellana) produce a prolific growth in the base of the trunk and roots, known as suckers, which are often removed in order to promote the development of a single trunk tree. Sucker removal facilitates cultural practices and mechanized operations, such as weed management and harvest. Sucker presence can...
A portion of this study was initiated to provide the
basis for implementing a chill unit accumulation procedure
in Yemen. Most continuous or daily minimum, maximum
temperature models severely underestimated chilling units,
and slight modifications offered little improvement for the
complex models. Only the Crossa Raynaud formula approximated
generally accepted...
Chilling requirements of 43 apple and 38 pear cultivars
were estimated over a 2 year period by cutting shoots in the
field at weekly intervals and forcing them in a warm
greenhouse for 4 weeks. For apples, the mean values ranged
from 490 Chill Units (CU) +- 1 for 'Dorsett...