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Bean CAP Snap Bean Diversity Panel Passport Data
No full textThe accessions used to create the Snap Bean Diversity Panel were 150 snap bean (Phaseolus vulgaris) cultivars and breeding lines selected from North American and European germplasm to create a population that is representative of the snap bean market class from a historical and geographical viewpoint. This panel was developed with support from the Common Bean Coordinated Agriculture Project (USDA-NIFA grant no. 2009-85606-05964). The passport data provides information on when and where these cultivars were developed. This panel has been genotyped using the Illumina Infinium Genechip BARCBEAN6K_3 platform. This SNP data has also been deposited in OSU ScholarsArchive and can be accessed using the link https://ir.library.oregonstate.edu/concern/datasets/m900p1589
Evaluating economic policy responses to appease growing dissent in tourism
No full textTourism is a major driver of global and local economies, yet rapid and uneven destination growth has intensified resident opposition and contributed to rising anti-tourism sentiment. These reactions stem from externalities such as congestion, housing pressures, and declining quality of life. Although prior research has examined these issues conceptually, progress has been limited by methodological complexity and the scarcity of comparable datasets across destinations. Traditional destination lifecycle models and economic frameworks offer only partial explanations, often overlooking the political and social mechanisms through which residents influence tourism development. A carrying-capacity perspective suggests that residents do not merely respond to tourism growth but actively shape it through political participation and social influence.
Policymakers have increasingly adopted tourism taxation to balance economic benefits with community needs, yet persistent challenges, such as short-term political incentives, weak alignment between tax instruments and underlying externalities, and the absence of long-term stewardship frameworks, constrain policy effectiveness. This research advances the field by integrating resident sentiment data, tourism tax structures, and lifecycle dynamics into an applied analytical framework. By refining and extending traditional models with new novel data, the study demonstrates how tourism economic policy can serve not only as a fiscal tool but as a core element of governance aimed at sustaining resident well-being and supporting the long-term resilience of destinations
Why the biggest Testudinidaes (giant tortoises) persist only on remote islands : a comparative evolutionary and ecological review
No full textGiant tortoises once occupied extensive continental and insular ranges across Africa, Asia, South America, Madagascar, the Mascarene Islands, and Oceania. Today, however, the largest surviving species—Aldabrachelys gigantea and the Chelonoidis niger complex—persist only on remote oceanic islands such as Aldabra and the Galápagos. This thesis investigates why giant tortoises survive exclusively in these isolated systems by integrating evidence from paleontology, island biogeography, comparative physiology, genomics, and historical ecology. Three primary hypotheses are evaluated: (1) physiological constraints, including extremely slow metabolism, delayed reproduction, and exceptional longevity, which restrict giant tortoises to low-predation, ecologically stable environments; (2) ecological isolation, whereby predator-free island ecosystems with simplified food webs, reduced competition, and stable climates create strong ecological release that favors large body size; and (3) anthropogenic timing, in which rapid extinctions followed early human arrival, overharvesting, habitat degradation, and invasive species on continents and many islands, while uniquely delayed human colonization allowed Aldabra and the Galápagos to retain giant tortoises into the modern era.
Comparative genomic evidence reveals deep mitochondrial divergence and long-term persistence of Galápagos lineages, consistent with prolonged survival in stable island environments. Fossil data further demonstrate that giant body size was once widespread on continents, suggesting that modern island giants may represent the last surviving remnants of an ancient large-bodied Testudinidae radiation rather than newly evolved cases of island gigantism. This emerging hypothesis raises the possibility that Aldabrachelys and Chelonoidis are insular dwarfs derived from even larger continental ancestors such as Megalochelys atlas.
The synthesis presented here shows that giant tortoise persistence is best explained by the interaction of slow-life physiological strategies, predator-free ecological conditions, and uniquely delayed human arrival on remote islands. Beyond resolving a major biogeographic paradox, this framework highlights remote islands as critical refugia for slow-reproducing megafauna and emphasizes the conservation importance of protecting the final strongholds of giant tortoises. The thesis concludes with a key unresolved question for future research: what combination of biological traits, oceanographic dynamics, and island environmental conditions enabled giant tortoises to disperse across vast ocean distances and establish enduring populations only on select remote islands
Pruning hazelnut trees -- a basic guide
No full textWhy train and prune hazelnut trees?
Training is done from planting up to 4–5 years old. It encourages a strong tree structure that can support heavy crops and withstand ice and snow loads.
Pruning is done to manage tree growth beyond its establishment phase and to give vigor to older trees. In hazelnuts, it is also a way to remove diseased or dead wood to extend the life of an orchard
Foods that fight cancer
No full textPublished April 2022.
Several factors can cause or contribute to cancer. These include genetics, radiation from sunlight, tobacco, environmental toxins or chemicals, alcohol, infections, chronic inflammation and viruses, including the human papillomavirus. Age, obesity, an unhealthy diet and a sedentary lifestyle can also lead to cancer.
Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: https://extension.oregonstate.edu
Integrating behavioral, chemical, and biological controls of Drosophila suzukii : an investigation into sustainability, efficacy, and microclimate interactions
No full textSpotted-wing drosophila (Drosophila suzukii Matsumura) is an invasive pest of soft- and stone-fruits that causes substantial economic losses worldwide due to its ability to oviposit in ripening fruit. Conventional control relies heavily on insecticide sprays, which are often unsustainable due to cost, non-target impacts, and resistance development. This thesis examines two key dimensions of sustainable management. First, the influence of fine-scale microclimatic variation on the efficacy of classical biological control utilizing the larval endoparasitoid Ganaspis kimorum and the loss of non-consumptive effects due to geographic isolation. Second, the compatibility of attract-and-kill (A&K) technologies with the adventively established larval parasitoid Leptopilina japonica. Field experiments over two seasons revealed that internal fruit temperatures often exceeded ambient air temperatures, particularly in detached sun-exposed fruit. Elevated temperatures reduced parasitoid emergence more than host emergence, creating possible microhabitat-level “ecological traps” in which oviposition occurred but development failed. Field experiments were paired with laboratory agitation trials to examine behavioral responses to parasitoid presence. No impacts on D. suzukii behavior and fecundity from non-consumptive effects were seen in either environment. Lack of response to threat cues may have been due to constrained spatial avoidance, thermally inhibited parasitoid activity, or a relaxed evolutionary recognition of G. kimorum as a threat in North American populations. Interannual climate variation further modulated outcomes, underscoring the vulnerability of thermally sensitive parasitoids to heat events in a warming climate. Complementary laboratory assays using a Drosophila Activity Monitor assessed the behavioral attraction and lethal effects of A&K formulations combining either the commercial attractant Combi-protec or alternative attractant molasses with spinosad (Entrust SC) or the sugar alcohol erythritol. Spinosad-based A&K baits caused moderate mortality in D. suzukii but also high mortality in L. japonica, whereas erythritol-based systems spared parasitoids but failed to suppress D. suzukii. Attraction responses indicated that lure–toxicant combinations influence pest orientation, and that molasses can perform comparably to proprietary lures as a low-cost substitute. Together, these findings highlight that successful integration of biological control into D. suzukii management requires aligning agent thermal resilience with microclimatic realities, and ensuring chemical tools are selectively lethal to pests while sparing beneficials. Mitigating thermal stress via shaded release sites or canopy management may improve G. kimorum establishment, while refining erythritol formulations and spatially targeting spinosad applications could balance pest suppression with natural enemy conservation. This work expands the call for integrated pest management strategies that explicitly account for Oregon’s changing climate and the safety of beneficial insects to achieve stable and ecologically sound suppression of D. suzukii
Functional analysis of cryptic biosynthetic gene clusters in bacteria
No full textBacteria are prokaryotic microorganisms that lack a nucleus, mitochondria or any other organelles.1 Mankind has benefited from bacterial evolutionarily diversified metabolism that produces a wide variety of small molecules.2 Small molecules that are essentials for bacterial growth, maintenance of cellular function, and reproduction are classified as primary metabolites. On the other hand, molecules that are not essential for their growth, development, or reproduction, but may play a role in their survival or adaptability in nature, are called secondary metabolites.3 Secondary metabolites or natural products (NPs) are optimized during the course of evolution, fine-tuned to serve specific or specialized functions for the producing organisms. Secondary metabolites exhibit diverse biological activities, such as antifungal, antibiotic, anti-cancer, antidiabetic and many others.4 In bacteria, a natural product is biosynthesized by a set of enzymes whose genes are clustered in a continuous region of the genome known as the biosynthetic gene cluster (BGC).5 As DNA sequencing and genomic-related technologies have improved significantly in recent years, more and more genomic information of bacteria became available and being explored or investigated. The results imply a vast and limitless possibility of unknown NPs to be discovered.6 For example, analysis of the soil bacteria Streptomyces genome data showed that a single Streptomyces genome may encode 25–50 BGCs and roughly 90% of them are silent or cryptic under standard laboratory conditions.7 Cryptic BGCs are defined as BGCs whose functions and/or products are not yet known. The metabolites may be produced in very little amount under standard laboratory conditions. On the other hand, silent BGCs refers to BGCs that are not expressed at all, thus no metabolites are produced.8 Among many cryptic BGCs in bacteria, we focused our investigation on a bacterial operon known as the ebo (eustigmatophyte-bacterial-operon) cluster, that are found in many Gram-(–) bacteria, including cyanobacteria (blue green algae), and eustigmatophytes.9 This cluster has been associated with the ability of Pseudomonas fluorescens NZI7 to repel the predatory nematode C. elegans,12 and the biosynthesis of the sunscreen compound scytonemin in Nostoc punctiforme.14 However, neither the pathway nor the product of the ebo cluster is known. We seek to characterize the biochemical activity of the ebo pathway and its metabolic product that may have significant ecological functions for the organisms. Bioinformatic studies showed that the core of the ebo cluster mainly consists of six genes, eboA, eboB, eboC, eboD, eboE, and eboF.9 Inactivation of these genes individually in P. fluorescens NZI7 resulted in the diminished ability of the mutants to produce certain indole derivatives that are responsible for its ability to repel C. elegans.12-13 Therefore, we cloned the ebo genes individually, produced the recombinant proteins in Escherichia coli, and performed enzymatic reactions in vitro to reconstitute the biosynthetic pathway. We were able to characterize the first committed step in the pathway, which is catalyzed by EboD, a novel sugar phosphate cyclase (SPC) enzyme. EboD is highly similar to 3-dehydroquinate synthase (DHQS)10 and 2-epi-5-epi-valiolone synthase (EEVS)10 but uniquely has a different substrate preference (mannose 6-phosphate) to produce a novel cyclic compound, 2-deoxy-4-epi-scyllo-inosose (DEI). It requires NAD+ as an electron-transfer cofactor and uses Co2+ or Ni2+ as the most preferred metal cofactor. This finding marks a new addition to the SPC family of enzymes, hence, EboD was named 2-deoxy-4-epi-scyllo-inosose synthase (DEIS).11
While the first committed step to the ebo pathway has been identified, further downstream the pathway is still unknown. Our efforts to characterize the biochemical functions of the other Ebo enzymes and their reactions sequence have not been successful. However, we hypothesize that EboC, which is a homolog of the ubiquinone prenyltransferase UbiA,15 may act last in the pathway, as the common substrates for UbiA-like enzymes are polyhydroxyl benzenes. Therefore, we conducted feeding experiments with P. fluorescens NZI7 ΔeboD using three possible hydroxylated benzenes [hydroxyquinol (1,2,4-trihydroxyl benzene), pyrogallol (1,2,3-trihydroxyl benzene), and phloroglucinol (1,3,5-trihydroxyl benzene)], one of which may be used as a substrate by EboC to produce the ebo product. The phenotypic production of indole derivatives was used as an indicator for the formation of the ebo product. Out of the three possible hydroxylated benzenes tested, phloroglucinol was able to complement the EboD inactivated pathway, resulted in the recovery of the wildtype phenotype . This result ssuggesting s that phloroglucinol is prenylated by EboC to produce the ebo product.
Next, we also discovered a conserved BGC highly similar to the ebo cluster in many Gram-(+) bacteria, particularly in the prolific producers of bioactive natural products the actinomycetes. The core genes are homologous to those found in the ebo cluster, except that the SPC gene eboD is missing. Instead, we found a new gene that encodes an enzyme that is highly similar to myo-inositol-1-phosphate synthase (MIPS). Therefore, the cluster was named the “mibo” cluster. We cloned the MIPS-like gene (sco6573) from Streptomyces coelicolor A3(2) and characterized its biochemical properties. We found that the MIPS-like enzyme Sco6573 uses the same substrate and metal cofactors (glucose-6-phosphate and Mg2+ or Ca2+) as MIPS but produces a slightly different product. In addition, this new enzyme uses NADP+, instead of NAD+, as a co-factor, and in contrast to MIPS reaction, the reduced co-factor NADPH was not recycled back NADP+, resulted in a non-reduced product, which is proposed to be 2-keto-myo-inositol-1-phosphate.
Subsequently, we knocked out the MIPS-like gene sco6573 in the model strain S. coelicolor A3(2), and as expected a distinct phenotypical difference was observed between the mutant and the wild-type. We observed that the production of the blue-colored antibiotic actinorhodin16 in the mutant was reduced significantly compared to the wildtype. Other metabolic differences were also observed when the samples were analyzed by HPLC and LC-MS. In addition, our bioinformatic analysis revealed that the mibo cluster is not only found in Gram-(+) bacteria, but also in archaea. This suggests that the small molecule(s) produced by the ebo or mibo clusters are important for the organisms, as the gene clusters seem to be conserved through million years of evolution.
In summary, the ebo cluster is conserved in many Gram-(–) bacteria and eustigmatophytes, whereas the mibo cluster is found in Gram-(+) bacteria and several archaea. Both clusters are hypothesized to produce a regulatory compound with a chemical structure similar to ubiquinones (prenylated polyhydroxyl benzenes). The first step of the ebo pathway is catalyzed by a sugar phosphate cyclase (EboD) that converts mannose 6-phosphate to 2-deoxy-4-epi-scyllo-inosose, whereas the mibo pathway starts with the conversion of glucose 6-phosphate to 2-keto-myo-inositol-1-phosphate catalyzed by a MIPS-like enzyme. Feeding experiments with three possible hydroxylated benzenes in Pseudomonas fluorescens NZI7 suggest that the ebo/EDB cluster product is a prenylated phloroglucinol. In S. coelicolor A3(2), the mibo cluster is involved in the regulation of secondary metabolite production. Overall, the results suggest that the ebo and the mibo clusters play a significant role in the survival and/or the well-being of the producing organisms
Fire-adapted communities : the next step in wildfire preparedness. Klamath County, Oregon
No full textThis is a manual that helps homeowners and neighborhoods prepare their areas and their homes for wildfire. A fire-adapted community is a community located in a fire-prone area that requires little assistance from firefighters during a wildfire. Residents of these communities accept responsibility for living in a high fire-hazard area. They possess the knowledge and skills to prepare their homes and property to survive wildfire; evacuate early, safely and effectively; and survive, if trapped by wildfire.
Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: https://extension.oregonstate.edu
Roguish Robots: Enhancing Robot Relatability Through Social Norm-Breaking
No full textIn personal and service robotics contexts, robot personalities have traditionally been polite, well-mannered, and inoffensive. At the same time, social robots can benefit from displaying emotions, even if they may not always conform to conventional politeness. To better understand robot expression through less well-mannered means, we conducted several exploratory studies using robots that break verbal social norms. We conducted two major research efforts to see if these robots were perceived as positively as their polite counterparts—an exploratory, in-the-wild deployment of a robotic poker dealer and three empirical studies of a robot that curses. In the first research effort, we used a design thinking framework to design and build a crass, playfully antagonistic robotic poker companion for use in a skilled nursing facility. We found that older adult residents in the skilled nursing facility enjoyed the robot and found it funny, but the staff in the facility were wary despite initial excitement about the idea. In the second research effort, we conducted two online studies and an in-person deployment of a robot that curses upon failure of a mock service task. We found that many users do not mind if robots curse and may even find it relatable and humorous. In this work, I present methods and results from both of these studies. I also discuss broader implications of robots that break social norms. This work seeks to broaden knowledge of how personal and service robots communicate and behave as social agents
Spatiotemporal controls on organic matter sourcing to minerogenic salt marshes
No full textSalt marshes are important carbon sinks; however, identification of the drivers of carbon burial rates is challenging because estuaries sit at terrestrial and marine interfaces. Here, we address the questions: what are the sources of organic matter sequestered in minerogenic salt marshes, and how do sources change through time? We characterized down-core sediment biogeochemistry (C : N, δ13C, δ15N) for the last century in seven Oregon USA high marshes and used a mixing model to elucidate differences in organic matter sources across estuaries and through time. Autochthonous biomass production consistently accounted for only half of overall organic matter accumulation, and the remainder was allochthonous, originating from a combination of estuarine and terrestrial sources. Salt marshes with high sediment loads buried more terrestrial organic matter, whereas those with low loads and substantial subtidal habitat buried more estuarine-derived organic matter. When assessed through depth/time, stable isotope trends indicated that decomposition is not the primary control. Instead, organic matter became increasingly more terrestrial in recent decades, especially in salt marshes with low fluvial loads. We hypothesize that salt marshes with lower loads took longer to regain lost elevation following coseismic subsidence of the 1700 ce Cascadia earthquake. This result magnifies the role of river floods in sediment and carbon accumulation on the marsh surface. Ultimately, the highest carbon burial rates coincided with highest fractions of terrestrially sourced organic matter, though spatiotemporal complexities obscured any potentially significant trends. While the term “blue” typically excludes terrestrial carbon, minerogenic salt marshes still perform the important ecosystem function of burying organic matter