With ever more inhibited programmes of excavation, new methods of site survey are always
welcome. Here a soil geomorphologist joins forces with archaeologists to read the history of
limestone blocks exposed on the surface at sites in southern Greece. Rillenkarren for example are
vertical grooves caused by rainfall on stones...
Reprinted March 1997. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
There has been keen interest in camelina (Camelina sativa L. Crantz) in recent years due to the unique fatty acid composition of the seed oil for human and animal consumption and, more importantly, the value of the seed oil to provide “green energy” to fuel commercial and military aircraft. The...
Background: The uneven distribution of recombination across the length of chromosomes results in inaccurate estimates of genetic to physical distances. In wheat (Triticum aestivum L.) chromosome 3B, it has been estimated that 90% of the cross over events occur in distal sub-telomeric regions representing 40% of the chromosome. Radiation hybrid...
The root-lesion nematode Pratylenchus (hornet is one of the most important pests restricting productivity of wheat in the Pacific Northwest (PNW). It is laborious and difficult to use microscopy to count and identify the nematodes in soils. A SYBR Green I-based real-time polymerase chain reaction (PCR) assay was developed to...
Foraging behaviors of bumble bee workers have been examined in natural habitats, whereas agricultural landscapes, which can provide insights on flight distances to fragmented patches of bloom, have received limited attention. In particular, information on worker flight distances to crops blooming several months after nests have been established is invaluable....
Horticultural nurseries are heterogeneous and spatially complex agricultural systems, which present formidable challenges to management of diseases and pests. Moreover, nursery plants shipped interstate and internationally can serve as important vectors for pathogens and pests that threaten both agriculture and forestry. Current regulatory strategies to prevent this movement of pathogens...
Experiments at the North Willamette Experiment Station have evaluated response of vegetables to lime and other fertilizers since 1970. The soils are moderately acid (pH 5.4 to 5.6), high in P, and better drained than most soils used for vegetable crop production in western Oregon. Typical soil acidity problems such...
Management of Italian ryegrass in cereal-based cropping systems continues to be a major production constraint in areas of the U.S.A., including the soft white winter wheat producing regions of the Pacific Northwest. Pyroxasulfone is a soil-applied herbicide with the potential to control broadleaf and grass weed species, including grass weed...
Palisade Russet is a medium-late maturing, lightly russeted potato cultivar notable for its resistance to late blight (Phytophthora infestans) infection of foliage and tuber. Palisade Russet is suitable for processing with low tuber glucose concentrations observed following long-term storage at a temperature as low as 5.6A degrees C with consistently...
Field studies were conducted in 2010 in Ontario, OR to evaluate the response of direct-seeded dry bulb onion, sugar beet, and pinto bean to imazosulfuron soil residues 12 months after application to control weeds in potato. The studies followed randomized complete block design with three replications each. Imazosulfuron was applied...
Field studies were conducted in 2011 at the Malheur Experiment Station, Ontario, OR and Prosser, WA to evaluate the effect of simulated glyphosate drift on direct-seeded dry bulb onion. Glyphosate was applied at 8.6, 25.8, 86, 290, 434, and 860 g ae ha⁻¹ when onion plants were at the flag-,...
Field trials were conducted in 2009 and 2010 near Paterson, WA and Ontario, OR to evaluate weed control and potato tolerance to PRE-applied pyroxasulfone, saflufenacil, and KSU12800 herbicides. Pyroxasulfone at 0.09 to 0.15 kg ai ha⁻¹ and saflufenacil at 0.05 to 0.07 kg ai ha⁻¹ applied PRE alone or in...
Yellow nutsedge is an important weed problem in the furrow irrigated fields in the Treasure Valley of eastern Oregon and southwestern Idaho. Field studies were conducted in 2008 and 2009 to evaluate the effect of PPI S-metolachlor or EPTC followed by POST halosulfuron and dicamba plus glyphosate or glyphosate alone...
Christmas tree needle sampling to evaluate nutrient need is an established practice. Data to support the recommended fall sampling time in Oregon and Washington was not found. In addition, the recommendation for needle sampling of Fraser fir in North Carolina was made without data from winter months. The goal for...
Kernel hardness or texture, used to classify wheat (Triticum aestivum L.) into soft and hard classes, is a major determinant of milling and baking quality. Wheat genotypes in the soft class that are termed 'extra-soft' (with kernel hardness in the lower end of the spectrum) have been associated with superior...
Genetic linkage maps have the potential to facilitate the genetic dissection of complex traits and comparative analyses of genome structure, as well as molecular breeding efforts in species of agronomic importance. Until recently, the majority of such maps was based on relatively low-throughput marker technologies, which limited marker density across...
Physical fractionation is a widely used methodology to study soil organic matter (SOM) dynamics, but concerns have been raised that the available fractionation methods do not well describe functional SOM pools. In this study we explore whether physical fractionation techniques isolate soil compartments in a meaningful and functionally relevant way...
The potato tuberworm, Phthorimaea operculella
(Zeller) (PTW), is one of the most important limitations to
potato, Solanum tuberosum L., productivity worldwide.
Leaves, stems, petioles and more importantly, potato tubers,
in the field and storage can be seriously affected. Due to the
relatively recent arrival of the PTWin the United States...
Camelina (Camelina sativa L. Crantz) has received worldwide attention in recent years as a biofuel crop and as a broadleaf option in cereal-based cropping systems. The objective of our 3-year study was to determine camelina seed yield and nitrogen use efficiency (NUE) as affected by six applied nitrogen (N) rates...
Suspected thifensulfuron resistant spiny annual sow-thistle was identified near Colfax, Washington, in two fields with a winter wheat and lentil rotation. Therefore, studies were conducted to examine resistance of spiny annual sow-thistle to thifensulfuron and cross-resistance to other acetolactate synthase inhibitors and to determine the physiological and molecular basis for...
Successful crop production depends initially on the availability of high-quality seed. By 2050 global climate change will have influenced crop yields, but will these changes affect seed quality? The present review examines the effects of elevated carbon dioxide (CO₂) and temperature during seed production on three seed quality components: seed...
A genetic map populated with RAD and SSR markers was created from F1 progeny of a stem rust-susceptible and stem rust-resistant parent of perennial ryegrass (Lolium perenne). The map supplements a previous map of this population by having markers in common with several other Lolium spp. maps including EST-SSR anchor...
In August of 2011, potato (Solanum tuberosum) tubers grown in the lower Columbia Basin of southern Washington State and northern Oregon were observed with internal discolorations suggestive of zebra chip disease (ZC). Symptoms included brown spots, streaks, and stripes in and near the vascular tissue, typical of ZC (1). Symptoms...
Woody encroachment has dramatically changed land cover patterns in arid and semiarid
systems (drylands) worldwide over the past 150 years. This change is known to influence bulk
soil carbon (C) pools, but the implications for dynamics and stability of these pools are not well
understood. Working in a Chihuahuan Desert...
Pratylenchus neglectus is one of the most widespread and economically important nematodes that invades plant roots and restricts wheat productivity in the Pacific Northwest. It is challenging to quantify P neglectus using microscopic methods for studies that require large-scale sampling, such as assessment of rotation crops, wheat cultivars, and other...
Ion exchange resin/soil cores are a common in situ approach to estimating soil nitrogen (N) mineralization rates. However, no studies compare the two common methods of core preparation (disturbed and undisturbed). The objective of our study was to compare N mineralized and soil temperature in disturbed versus undisturbed cores of...
Biochars have potential value for greenhouse nurseries as a potting amendment, reducing the need for environmentally costly products currently in use. The onsite manufacture of biochars by pyrolysis of woody waste offers additional greenhouse value as a source of clean heat. However, recent work observed that some biochars may evolve...
Cultivars of several cereal crops have been developed with acetohydroxyacid synthase (AHAS)
insensitivity to imidazolinone herbicides and are now an important tool for weed management.
Options for screening for imidazolinone resistant lines include direct herbicide application,
biochemical assays for AHAS activity and DNA-based methods. Herbicide and biochemical
assays for AHAS...
Since a NanoSIMS high-resolution secondary ion mass spectrometry instrument was first used for cosmochemistry investigations over a decade ago, both interest in NanoSIMS and the number of instruments available have significantly increased. However, SIMS comes with a set of challenges that are of both technical and conceptual nature, particularly for...
Hop powdery mildew [Podosphaera macularis (Wallr.) U. Braun & S. Takam.] is best controlled via the production of resistant varieties. Recent evidence supports selection against plant susceptibility genes to fungal pathogens as a more durable resistance mechanism than selection for resistance genes. The objective of this study was to identify...
Genetic information for male and female hop accessions is limited, hampering
parental selection to maximize offspring productivity. Our objective
was to determine whether amplified fragment length polymorphism (AFLP)-derived genetic distance (GD[subscript mm]) estimates and coancestry estimates from
pedigrees (GS[subscript ped]) between parental pairs could be used to predict offspring
performance....
Hop (Humulus lupulus L.) is cultivated for the female flowers, or “cones,” which traditionally have been used as a bittering and flavoring agent in beer. Hop breeding historically relied on relatively simple selection techniques within established breeding lines. Supplementing current breeding material with new genetic sources would enhance a hop...
’Teamaker’ hop (Humulus lupulus L.) (Reg. No. CV-28,
PI 558864) was developed by the USDA-ARS as a unique,
nonbittering, high beta-acids hop and was released on 26 June
2006. The defining characteristics of Teamaker are its near-zero
percent alpha acids levels—a distinctive condition in the Humulus
species (Haunold et al.,...
Hop (Humulus lupulus L.) is a perennial, dioecious species in which the female inflorescence (cones) are harvested and used in the beer-brewing process to impart bittering and/or flavoring to beer. Hop breeders have typically utilized clonal selection and hybridization to develop new cultivars. The use of genetically diverse parents for...
Hop (Humulus lupulus L. var. lupulus) is grown worldwide for the production of the dried female inflorescence (strobulus), or cones, used principally for the bittering and flavoring of beer. Information is scant on the inheritance of traits of economic importance in hop, and present knowledge is based on historical data...
Identification of heterotic groups and patterns among breeding populations provides fundamental information to help plant breeders more knowledgeably manipulate heterosis. A diallel analysis was conducted among nine alfalfa (Medicago sativa L.) germplasms, commonly referred to as African, Chilean, Flemish, Indian, Ladak, M. falcata, M. varia, Peruvian, and Turkistan, which represent...
Hop is a dioecious perennial with female plants grown commercially
for brewing purposes. Parent selection in hop breeding on the basis of
heterotic potential has not been reported in literature even though dominance
has been reported in hops for several economically important traits.
The objectives of this study were to...
NM-9D11A-AN3 alfalfa (Medicago sativa L.) germplasm
(Reg. no. GP-337, NSL 386506) was developed by the New
Mexico Agricultural Experiment Station and released 5 Oct.
1998. NM-9D11A-AN3 has demonstrated high yield potential
under deficit irrigated field conditions in southern New Mexico.
It is highly resistant to anthracnose (caused by Colletotrichum trifolii...
Solid and aqueous phase Al species are recognized to affect organic matter (OM) stabilization in forest soils. However, little is known about the dynamics of formation, composition and dissolution of organo-Al hydroxide complexes in microbially-active soil systems, where plant litter is subject to microbial decomposition in close proximity to mineral...
Climate change models predict that future precipitation patterns will entail lower-frequency but larger rainfall events, increasing the duration of dry soil conditions. Resulting shifts in microbial C cycling activity could affect soil C storage. Further, microbial response to rainfall events may be constrained by the physiological or nutrient limitation stress...
Microsclerotia (MS) production by two isolates of Lecanicillium lecanii on various culture media is described, and the efficacy of MS against western flower thrips is evaluated. High concentrations of MS (2.9-3.1×10⁵•mL⁻¹) were produced in media with C: N ratios of 7.4:1 and 10.3:1 by isolate SN21. Bioassays using soil-incorporated MS...
Ammonia (NH₃)-oxidizing bacteria (AOB) and thaumarchaea (AOA) co-occupy most soils, yet no short-term growth-independent method exists to determine their relative contributions to nitrification in situ. Microbial monooxygenases differ in their vulnerability to inactivation by aliphatic n-alkynes, and we found that NH₃ oxidation by the marine thaumarchaeon Nitrosopumilus maritimus was unaffected...
It is well known that the ratio of ammonia oxidizing archaea (AOA) and bacteria (AOB) ranges widely in soils, but no data exist on what might influence this ratio, its dynamism, or how changes in relative abundance influences the potential contributions of AOA and AOB to soil nitrification. By sampling...
Research in warm-climate biomes has shown that invasion by symbiotic dinitrogen (N₂)-fixing plants can transform ecosystems in ways analogous to the transformations observed as a consequence of anthropogenic, atmospheric nitrogen (N) deposition: declines in biodiversity, soil acidification, and alterations to carbon and nutrient cycling, including increased N losses through nitrate...
This paper examines the sources of uncertainty for the Forced Diffusion (FD) chamber soil respiration (Rs) measurement technique and demonstrates a protocol for uncertainty quantification that could be appropriate with any soil flux technique. Here we sought to quantify and compare the three primary sources of uncertainty in Rs: (1)...