Pathogenicity of Fungi Associated with the Wheat Crown Rot Complex in Oregon and Washington

Crown rot of wheat in the Pacific Northwest is caused by a complex including Bipolaris sorokiniana, Fusarium avenaceum, F. culmorum, F. pseudograminearum, and Microdochium nivale. Relative pathogenicity was examined under greenhouse conditions for 178 isolates of the five species, and under field conditions for 24 isolates of B. sorokiniana, F. culmorum, and F. pseudograminearum. In the greenhouse, all five species reduced (P < 0.05) plant height relative to noninoculated controls. Disease severity was inversely correlated with plant height for the three Fusarium spp. In one or more of four experiments with spring wheat in the field, all three species reduced stand establishment and density of mature heads and increased the incidence and severity of crown rot. F. culmorum and F. pseudograminearum caused the greatest disease severity and plant damage and were the only pathogens that reduced grain yield. Virulence ratings were variable among isolates for each species in all greenhouse and field experiments. Isolate variability was especially high for the location and year variables in field experiments. Mixtures of multiple isolates are required for future research.

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Optimum Timing of Preplant Applications of Glyphosate to Manage Rhizoctonia Root Rot in Barley

Plant Disease ◽

10.1094/pdis-05-10-0354 ◽

2011 ◽

Vol 95 (3) ◽

pp. 304-310 ◽

Cited By ~ 19

Author(s):

E. M. Babiker ◽

S. H. Hulbert ◽

K. L. Schroeder ◽

T. C. Paulitz

Keyword(s):

Disease Severity ◽

Pacific Northwest ◽

Root Rot ◽

Field Experiments ◽

Herbicide Application ◽

Rhizoctonia Root Rot ◽

The Pacific ◽

Seminal Roots ◽

Polymerase Chain ◽

High Level

Rhizoctonia root rot, caused by Rhizoctonia solani AG-8 and R. oryzae, is considered one of the main deterrents for farmers to adopt reduced-tillage systems in the Pacific Northwest. Because of the wide host range of Rhizoctonia spp., herbicide application before planting to control weeds and volunteer plants is the main management strategy for this disease. To determine the effect of timing of glyphosate applications on the severity of Rhizoctonia root rot of barley, field experiments were conducted in 2007, 2008, and 2009 in a field naturally infested with a high level of both R. solani and R. oryzae. Crop volunteer plants and weeds were allowed to grow over the winter and plots were sprayed with glyphosate at 42, 28, 14, 7, and 2 days prior to planting. As the herbicide application interval increased, there were significant increases in shoot length, length of the first true leaf, and number of healthy seminal roots and a decrease in disease severity. Yield and the number of seminal roots did not show a response to herbicide application interval in most years. The activity of R. solani, as measured by toothpick bioassay and real-time polymerase chain reaction, declined over time in all treatments after planting barley. The herbicide application interval required to meet 80 and 90% of the maximum response (asymptote) for all plant and disease measurements ranged from 11 to 27 days and 13 to 37 days, respectively. These times are the minimum herbicide application intervals required to reduce disease severity in the following crop.

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Crop Damage Estimates for Crown Rot of Wheat and Barley in the Pacific Northwest

Plant Disease ◽

10.1094/pd-89-0595 ◽

2005 ◽

Vol 89 (6) ◽

pp. 595-604 ◽

Cited By ~ 129

Author(s):

Richard W. Smiley ◽

Jennifer A. Gourlie ◽

Sandra A. Easley ◽

Lisa-Marie Patterson ◽

Ruth G. Whittaker

Keyword(s):

Pacific Northwest ◽

Wheat Yield ◽

Soil Surface ◽

Bipolaris Sorokiniana ◽

Grain Protein Content ◽

Kernel Weight ◽

Crown Rot ◽

Crop Damage ◽

Infested Soil ◽

The Pacific

Crown rot of wheat and barley in the Pacific Northwest is caused by a complex of Fusarium pseudograminearum, F. culmorum, F. avenaceum, Bipolaris sorokiniana, and Microdochium nivale. Yield-loss estimates were made by evaluating yield components on tillers collected from commercial fields and sorted by disease severity classes, and by comparing yields for field plots inoculated with F. pseudograminearum with yields in naturally infested soil. Increasing crown rot severity caused an increase in grain protein content and reduction in grain yield, kernels per head, kernel weight, test weight, tiller height, and straw weight. Crown rot reduced winter wheat yield as much as 1,550 kg/ha (35%, $219/ha) in commercial fields, with a 13-field mean of 9.5% ($51/ha). Inoculation reduced yields as much as 2,630 kg/ha (61%, $372/ha) over that caused by the native pathogen flora. Rain-induced crusting of the soil surface greatly amplified preemergence damping-off caused by F. pseudograminearum. Crown rot caused the greatest losses during seasons of lowest precipitation but also damaged crops under wet conditions. Aboveground symptoms were not always apparent under conditions of moderate infection and yield constraint. Damage from crown rot in the Pacific Northwest is more widespread and damaging than previously recognized.

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Effect of Climate on the Distribution of Fusarium spp. Causing Crown Rot of Wheat in the Pacific Northwest of the United States

Phytopathology ◽

10.1094/phyto-07-12-0181-r ◽

2013 ◽

Vol 103 (11) ◽

pp. 1130-1140 ◽

Cited By ~ 27

Author(s):

Grant J. Poole ◽

Richard W. Smiley ◽

Carl Walker ◽

David Huggins ◽

Richard Rupp ◽

...

Keyword(s):

United States ◽

Factor Analysis ◽

Pacific Northwest ◽

The United States ◽

Crown Rot ◽

Mean Annual Precipitation ◽

Mean Annual Temperature ◽

Fusarium Spp ◽

Mean Temperature ◽

The Pacific

Fusarium crown rot (FCR) is one of the most widespread root and crown diseases of wheat in the Pacific Northwest (PNW) of the United States. Our objectives were to characterize crown rot severity and distribution throughout the PNW by conducting a survey of 210 fields covering the diverse dryland wheat-producing areas of Washington and Oregon and to utilize a factor analysis statistical approach to determine the effects of climate and geography on species distribution and disease severity. Climatic variables were based on 30-year averages and 2008 and 2009 separately (the 2 years of the survey). Mean annual temperature, mean temperature in the coldest month, mean temperature in the warmest month, mean annual precipitation, snowfall, elevation, soil type, and cropping intensity were highly intercorrelated. The factor analysis of the climate variables resulted in the development of two latent factors that could be used as predictor variables in logistic regression models for the presence or absence of Fusarium spp. and of FCR disease scores. Isolates of Fusarium spp. were recovered from 99% of 105 fields sampled in 2008 and 97% of fields in 2009. There were differences between years for responses of FCR and nodes scores, and isolations of Fusarium pseudograminearum with more significant results in 2008, due to warmer drier weather. Results of the factor analysis showed that the distribution of F. pseudograminearum occurred in a greater frequency in areas of the PNW at lower elevations with lower moisture and higher temperatures in 2008, whereas F. culmorum occurred in greater frequency in areas at higher elevations with moderate to high moisture and cooler temperatures consistently across both years. Disease scores increased with increasing levels of factors 1 (primarily temperature) and 2 (primarily precipitation). Both the frequency of pathogen species and disease scores were influenced by the year, indicating that soilborne pathogens are responsive to short-term changes in environment. This factor analysis approach can be utilized in studies to determine the effects of climate and other environmental (soil, cropping system, and so on) factors on the distribution and severity of root diseases.

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Genetic interactions Between Hatchery and Wild Salmonids: Lessons from the Pacific Northwest

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f91-311 ◽

1991 ◽

Vol 48 (S1) ◽

pp. 124-133 ◽

Cited By ~ 259

Author(s):

Robin S. Waples

Keyword(s):

Pacific Northwest ◽

Genetic Effects ◽

Wild Fish ◽

Genetic Interactions ◽

Future Research ◽

Management Options ◽

Genetic Changes ◽

The Pacific ◽

Genetic Risks ◽

Northwestern North America

The potential for genetic interactions between hatchery and wild populations of salmonids in northwestern North America has increased considerably in recent decades. Efforts to mitigate severe losses to many wild stocks caused by overfishing, destruction of habitat, and blockage of migratory routes have focussed on boosting artificial production in public hatcheries. Opportunities for genetic interactions between hatchery and wild fish will increase if efforts to supplement wild production with hatchery-reared fish continue. Concerns center on three issues: (1) direct genetic effects (caused by hybridization and introgression); (2) indirect genetic effects (principally due to altered selection regimes or reductions in population size caused by competition, predation, disease, or other factors); and (3) genetic changes to hatchery stocks (through selection, drift, or stock transfers), which magnify the consequences of hybridization with wild fish. Strategies for minimizing these genetic risks and monitoring the consequences of various management options are discussed, and some important areas for future research are identified.

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Changing wildfire, changing forests: the effects of climate change on fire regimes and vegetation in the Pacific Northwest, USA

Fire Ecology ◽

10.1186/s42408-019-0062-8 ◽

2020 ◽

Vol 16 (1) ◽

Cited By ~ 8

Author(s):

Jessica E. Halofsky ◽

David L. Peterson ◽

Brian J. Harvey

Keyword(s):

Pacific Northwest ◽

Fire Regimes ◽

Tree Regeneration ◽

Ecosystem Change ◽

Fire Intensity ◽

Future Research ◽

Fuel Treatments ◽

Warming Climate ◽

Resource Managers ◽

The Pacific

Abstract Background Wildfires in the Pacific Northwest (Washington, Oregon, Idaho, and western Montana, USA) have been immense in recent years, capturing the attention of resource managers, fire scientists, and the general public. This paper synthesizes understanding of the potential effects of changing climate and fire regimes on Pacific Northwest forests, including effects on disturbance and stress interactions, forest structure and composition, and post-fire ecological processes. We frame this information in a risk assessment context, and conclude with management implications and future research needs. Results Large and severe fires in the Pacific Northwest are associated with warm and dry conditions, and such conditions will likely occur with increasing frequency in a warming climate. According to projections based on historical records, current trends, and simulation modeling, protracted warmer and drier conditions will drive lower fuel moisture and longer fire seasons in the future, likely increasing the frequency and extent of fires compared to the twentieth century. Interactions between fire and other disturbances, such as drought and insect outbreaks, are likely to be the primary drivers of ecosystem change in a warming climate. Reburns are also likely to occur more frequently with warming and drought, with potential effects on tree regeneration and species composition. Hotter, drier sites may be particularly at risk for regeneration failures. Conclusion Resource managers will likely be unable to affect the total area burned by fire, as this trend is driven strongly by climate. However, fuel treatments, when implemented in a spatially strategic manner, can help to decrease fire intensity and severity and improve forest resilience to fire, insects, and drought. Where fuel treatments are less effective (wetter, high-elevation, and coastal forests), managers may consider implementing fuel breaks around high-value resources. When and where post-fire planting is an option, planting different genetic stock than has been used in the past may increase seedling survival. Planting seedlings on cooler, wetter microsites may also help to increase survival. In the driest topographic locations, managers may need to consider where they will try to forestall change and where they will allow conversions to vegetation other than what is currently dominant.

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THE PALEOBOTANY AND PALEOECOLOGY OF THE EOCENE HERREN BEDS OF NORTH-CENTRAL OREGON, USA

Palaios ◽

10.2110/palo.2019.014 ◽

2019 ◽

Vol 34 (9) ◽

pp. 424-436 ◽

Cited By ~ 1

Author(s):

ANTHONY P. JIJINA ◽

ELLEN D. CURRANO ◽

KURT CONSTENIUS

Keyword(s):

Pacific Northwest ◽

Middle Eocene ◽

Plant Macrofossils ◽

Mean Annual Precipitation ◽

Future Research ◽

Mean Annual Temperature ◽

Leaf Margin ◽

North Central ◽

The Pacific ◽

Margin Analysis

ABSTRACT New collections of plant macrofossils and radiometric dates from the Herren beds of north-central Oregon provide the opportunity to document floral communities and calculate foliar-derived climate estimates from the warm early Eocene and the cooler middle Eocene. Plant macrofossils were collected from one fluvial site at East Birch Creek approximately 2 m below a 51.9 ± 0.9 Ma tuff. Collections were also made at two co-occurring fluvial sites at Arbuckle Mountain, whose ages are constrained to ca. 44.5–43.8 Ma based on a dated tuff from Willow Creek (44.5 ± 0.8 Ma) and reported ages for the overlying Clarno Formation. Floral findings show an almost complete vegetation overturn, with only two genera (Glyptostrobus and Allantodiopsis) appearing in both floras. Both floras are species poor, but the older East Birch Creek flora has higher richness and evenness than the younger Arbuckle Mountain flora. The four named genera at East Birch Creek are taxa found throughout Eocene North America; named genera at Arbuckle Mountain also include taxa restricted to the Pacific Northwest. Leaf margin analysis and leaf area analysis of the East Birch Creek community suggest a warmer and possibly wetter (mean annual temperature 23.4 ± 4.3 °C; mean annual precipitation 206 +89, -63 cm) climate than the Arbuckle Mountain flora (16.4 ± 4.2 °C; 165 +50, -71.4 cm). This research provides a framework for future research on Eocene floristic, environmental, and climatic trends of the Pacific Northwest.

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Disentangling Post-Fire Logging and High-Severity Fire Effects for Spotted Owls

Birds ◽

10.3390/birds2020011 ◽

2021 ◽

Vol 2 (2) ◽

pp. 147-157

Author(s):

Chad T. Hanson ◽

Derek E. Lee ◽

Monica L. Bond

Keyword(s):

Pacific Northwest ◽

Forest Type ◽

Fire Effects ◽

Future Research ◽

Spotted Owl ◽

High Severity ◽

Adverse Impacts ◽

The Pacific ◽

Spotted Owls ◽

The Usa

The Spotted Owl is a rare and declining raptor inhabiting low/middle-elevation forests of the Pacific Northwest, California, and the Southwest in the USA. It is well established that Spotted Owls select dense, mature, or old forests for nesting and roosting. High-severity fire transforms such forests into a unique forest type known as “snag forest habitat”, which the owls select for foraging. This habitat is disproportionately targeted by post-fire logging projects. Numerous recent articles have explored the influence of high-severity fire and post-fire logging on this species. Studies have shown that post-fire logging significantly reduces Spotted Owl occupancy, but efforts have generally not been made to disentangle the effects of such logging from the influence of high-severity fire alone on Spotted Owls. We conducted an assessment of published, peer-reviewed articles reporting adverse impacts of high-severity fire on Spotted Owls, exploring the extent to which there may have been confounding factors, such as post-fire logging. We found that articles reporting adverse impacts of high-severity fire on Spotted Owls were pervasively confounded by post-fire logging, and in some cases by a methodological bias. Our results indicate a need to approach analyses of high-severity fire and Spotted Owls differently in future research.

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Walking the Path: A New Journey to Explore and Discover Through Visual Analytics

Information Visualization ◽

10.1057/palgrave.ivs.9500133 ◽

2006 ◽

Vol 5 (4) ◽

pp. 237-249 ◽

Cited By ~ 4

Author(s):

Pak Chung Wong ◽

Stuart J Rose ◽

George Chin ◽

Deborah A Frincke ◽

Richard May ◽

...

Keyword(s):

Pacific Northwest ◽

Homeland Security ◽

Visual Analytics ◽

National Laboratory ◽

Pacific Northwest National Laboratory ◽

Future Research ◽

Department Of Homeland Security ◽

Professional Activities ◽

Analytical Reasoning ◽

The Pacific

Under the leadership of the US Department of Homeland Security (DHS), researchers at the Pacific Northwest National Laboratory (PNNL) established a research center focusing on the discipline of visual analytics in 2004. A year later, the center led a multidisciplinary panel representing academia, industry, and government to formally define directions and priorities for future research and development (R&D) for visual analytics tools. The R&D agenda, Illuminating the Path, defines the term visual analytics as ‘the science of analytical reasoning facilitated by interactive visual interfaces’. This article describes our progress to date in walking that path. We briefly describe the background of the subject, present major professional activities and accomplishments of its community, and highlight some of the ongoing R&D efforts being carried out by researchers at PNNL to fulfill the requirements and missions of a new discipline that promises to change the way we deal with today's information.

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Experiences of Divine Grace Among Christian Friends

Journal of Psychology and Theology ◽

10.1177/0091647121992415 ◽

2021 ◽

pp. 009164712199241

Author(s):

Kyle T. Webster ◽

Mark R. McMinn ◽

Irene H. Dunlop ◽

Glena L. Andrews ◽

William Buhrow ◽

...

Keyword(s):

Grounded Theory ◽

Pacific Northwest ◽

Psychology Of Religion ◽

Structured Interview ◽

Future Research ◽

Present Moment ◽

Divine Grace ◽

The Pacific ◽

Conservative Christian ◽

Relational Experience

Although topics of prayer, forgiveness, and gratitude have received attention in the psychology of religion, there is sparse literature regarding the concept of grace. Thirty interviews were conducted with Friends (Quakers) in the Pacific Northwest, using a semi-structured interview developed for a larger study of how Christians from various denominations experience grace. Four organizing themes were derived from the interview questions and then grounded theory was used to uncover associated subthemes within each organizing theme. Participants emphasized the loving nature of God and how grace is a transforming relational experience with God that helps people move toward wholeness and completeness. Although participants sometimes linked grace with questions of eternal destiny, it was also associated with being fully accepted and loved by God in the present moment. Many expressed concerns about conservative Christian perspectives of grace that seem to overly focus on being saved from hell, instead preferring views of grace that are inclusive and available to all. Ongoing disciplines of grace included being in nature, community relationships, creative expressions, prayer, quiet, and reading sacred texts. These findings are consistent with historical and contemporary distinctives of Friends. Implications for future research are considered.

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Ectoparasitic nematodes: emerging challenges to wine grape production in the Pacific Northwest of North America.

10.1079/9781789247541.0027 ◽

2021 ◽

pp. 192-198

Author(s):

Inga Zasada ◽

Tom Forge

Keyword(s):

North America ◽

Pacific Northwest ◽

Integrated Management ◽

Future Research ◽

Parasitic Nematodes ◽

Wine Grape ◽

Plant Parasitic Nematodes ◽

The Pacific ◽

Ectoparasitic Nematodes ◽

Plant Parasitic

Abstract Plant parasitic nematodes are a constraint to the production of wine grapes worldwide. In the Pacific Northwest (PNW) of North America, including British Columbia (BC) in Canada and Oregon (OR) and Washington (WA) in the United States, the impact of plant parasitic nematodes, specifically ectoparasitic nematodes, on wine grape production has not been extensively studied or documented. This chapter discusses the economic importance, geographical distribution, host range, damage symptoms, biology and life cycle, interactions with other nematodes and pathogens, and recommended integrated management of Mesocriconema xenoplax and Xiphinema americanum infesting grapes in North America. Future research requirements and future developments are also mentioned.

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