Fungal hyphae are among the most highly polarized cells. Hyphal polarized growth is supported by tip-directed transport of secretory vesicles, which accumulate temporarily in a stratified manner in an apical vesicle cluster, the Spitzenkörper. The exocyst complex is required for tethering of secretory vesicles to the apical plasma membrane. We...
For the past several decades, amphibian populations have been decreasing
around the globe at an unprecedented rate. Batrachochytrium dendrobatidis (Bd), the fungal
pathogen that causes chytridiomycosis in amphibians, is contributing to amphibian declines.
Natural and anthropogenic environmental factors are hypothesized to contribute to these
declines by reducing the immunocompetence of...
The use of high throughput molecular methods that allow for the study of bacterial communities in environmental samples is commonplace in microbial ecology. Until recently, fungal community ecology has
focused on isolation, collection of sporocarps, or collection of ectomycorrhizal roots. The techniques used to extract and amplify DNA from environmental...
Contributing to the worldwide biodiversity crisis are emerging infectious diseases, which can lead to extirpations and extinctions of hosts. For example, the infectious fungal pathogen Batrachochytrium dendrobatidis (Bd) is associated with worldwide amphibian population declines and extinctions. Sensitivity to Bd varies with species, season, and life stage. However, there is...
Coastal Douglas-fir (Pseudotsuga menziesii var. menziesii), a keystone species in the Pacific Northwest, relies on symbioses with microorganisms to obtain nutrients, potentially defend against pathogens, and perform a variety of other tasks. Two of the tree’s primary fungal symbionts are foliar epiphytes and endophytes, which reside on the exterior or...
The isoprenoid pathway is one of the major biosynthetic pathways of secondary metabolites. Isoprenoids with a C₂₀ skeleton are known as diterpenoids and are derived from the common precursor, geranylgeranyl diphosphate (GGPP). This dissertation describes approaches to discover the diterpene synthase enzymes which provide the backbone structures for pleuromutilin and...
This study was initiated to determine the tolerance to copper
of Aspergillus niger, Stemphylium sarcinaeforme, Monilinia
fructicola and Fusarium oxysporum f. sp. lycopersici. Included
were strains of the latter two fungi that were induced to tolerate
relatively high levels of copper by continual culture on sublethal
levels of the toxicant....
The fungi that cause mold and stain of freshly sawn lumber result in millions of dollars in losses to the forest products industry. Stain and mold are typically prevented by either kiln drying or by application of a topical fungicide. While these treatments are effective, kiln drying is costly and...
Oomycetes are an important group of organisms with a variety of ecological roles similar to fungi. Although many are well-studied plant pathogens known for their devastating effects on agricultural systems, most are little-studied saprobes and parasites of plants and animals in nearly every ecosystem on earth. The advent of affordable...
Fungi are the primary biological agents of wood deterioration and cause major economic losses of wood products globally. Wood in outdoor applications tends to remain wet for extended time periods, making it susceptible to fungal attack. Understanding the factors involved in fungal colonization of wood is important for developing improved...
Spalting fungi show strong potential as natural colorants on a variety of materials, specifically textiles and wood. Four species of spalting fungi are currently utilized in this manner: Scytalidium cuboideum, which produces a red pigment called draconin red, Scytalidium ganodermophthorum, that produces an unknown yellow pigment, and Chlorociboria aeruginosa and...
Fungal pathogens tend to accumulate within styroblock containers, which are reused to produce successive crops of container-grown seedlings. Most nurseries treat reused containers by immersing them in hot water for varying time periods. The efficacy of radio frequency waves (RFs) to reduce levels of selected groups of fungi within styroblock...
Metamorphosis is often characterized by profound changes in morphology and physiology that can affect the dynamics of species interactions. For example, the interaction between a pathogen and its host may differ depending on the life stage of the host or pathogen. One pathogen that infects hosts with complex life cycles...
Wildlife epidemiological outcomes can depend strongly on the composition of an ecological community, particularly when multiple host species are affected by the same pathogen. However, the relationship between host species richness and disease risk can vary with community context and with the degree of spillover transmission that occurs among co-occurring...
The purposes of this investigation were twofold:
1. To determine important criteria for making a selection of
course content in general biology.
2. To ascertain what should be the content emphasis in
biology for the purposes of general education at the freshman
college level.
The literature pertinent to the problem...
Commercial methodologies for producing fungal pigments are of worldwide interest due to the desire to move away from synthetic dyes. Chlorociboria species and Scytalidium species have been reported to produce sufficient yields of pigments for commercial production and have attracted special attention because of their use in spalted wood applications....
Previous studies have indicated that roots from five tree species (Picea sitchensis, Tsuga heterophylla, Pseudotsuga menziesii, Pinus ponderosa, and Pinus contorta) decompose at different rates across an environmental gradient in Oregon. Measurements of wood chemistry from each tree species as well as moisture and
temperature from each location do not...
An evaluation of the efficacy of steam treatment on reducing levels of Fusarium, Cylindrocarpon, and
Trichoderma within styroblock containers was conducted at the Plum Creek Nursery in Pablo, Montana. Although levels, of both Fusarium and Cylindrocarpon were significantly reduced by cleaning, relatively high populations of both these fungi persisted after...
Distinct aggregations of fungal hyphae and rhizomorphs, or "mats", formed by some genera of ectomycorrhizal (EcM) fungi are common features of soils in coniferous forests of the Pacific Northwest. We measured in situ respiration rates of Piloderma mats and neighboring non-mat soils in an old-growth Douglas-fir forest in western Oregon...
This book is based on a project to completely annotate what is known about the function of the ~150 genes encoded by the genome of the most commonly investigated baculovirus, AcMNPV. Once the annotation was completed (summarized in Chapter 11), the material was organized into a series of chapters integrating...
Associations between the golden metallic beetle, Buprestis aurulenta L., and wood-destroying fungi were explored with adult beetles collected from log decks. A variety of fungi were isolated from the beetle bodies by four methods. A total of 863 isolations were made from 59 females and 21 males. There was no...
This book is based on a project to completely annotate what is known about the function of the ~150 genes encoded by the genome of the most commonly investigated baculovirus, AcMNPV. Once the annotation was completed (summarized in Chapter 12), the material was organized into a series of chapters integrating...
Impact bending and breaking radius were used to measure loss in toughness caused by basidiomycetes isolated from wood. Small test pieces were used to accelerate testing. Wide differences were found among, and sometimes within, the 26 species tested. Brown-rot fungi tended to cause greater losses than white-rot fungi, but no...
This is the 4th edition of a book that was initiated with the annotation of the function of all the genes in the most commonly studied baculovirus, AcMNPV. It has been almost six years since I reviewed this literature. As a measure of the research that has occurred over this...
This is the third edition of a book that was initiated with the annotation of the function of all the genes in the most commonly studied baculovirus, AcMNPV. The second and third editions involved the update of this information and its integration into chapters covering the major processes central to...
Batrachochytrium dendrobatidis (hereafter Batrachochytrium), a fungal pathogen of amphibians, causes the disease chytridiomycosis which is responsible for unprecedented population declines and extinctions globally. Host defenses against chytridiomycosis include cutaneous symbiotic bacteria and anti-microbial peptides, and proposed treatment measures include use of fungicides and bioaugmentation. Efforts to eradicate the fungus from...
Although chemical fungicides are commonly used to control fungal soil-borne
diseases of Easter lilies, Lilium longiflorum Thunb., in field production and
greenhouse forcing, cultural and biological controls may be alternatives or
complementary to chemicals for control of pathogens.
The influence of inoculations with beneficial, symbiotic, and biocontrol
microorganisms to enhance...
Species composition within ecological assemblages can drive disease dynamics including pathogen invasion, spread, and persistence. In multi-host pathogen systems, interspecific variation in responses to infection creates important context dependency when predicting the outcome of disease. Here, we examine the responses of three sympatric host species to a single fungal pathogen,...
Degradation of lignin to simpler compounds is desirable for removing residual lignin during paper manufacture and accessing biomass carbohydrates for biofuel production, among other purposes. Lignin transformation using enzymes found in white rot fungi, some of nature's most efficient lignin-degrading organisms, offers a more environmentally benign, selective, and possibly less...
The objective of this dissertation is to introduce low-cost processing methods for the fabrication of ZnO transparent thin-film transistors (TTFTs). A novel method for depositing ZnO body layers via spin-coating of a zinc nitrate-based spin solution is presented. The processing conditions of spin-coated ZnO are optimized to produce continuous and...
Analytical chemistry is an area of chemistry primarily focused on the study and use of instruments for separation, identification, and quantification of an analyte of interest. Specifically, separation science within analytical chemistry often refers to the process of dividing mixtures into their small component parts based on differences in their...
Grape phylloxera (Daktulosphaira vitifoliae), a root-feeding aphid-like insect, is the most important pest of European winegrape vineyards worldwide. They cannot be controlled on infested vines which eventually die. There are currently no satisfactory chemical or biological control methods for this pest; its management throughout the world has been by planting...
Xylona heveae has only been isolated as an endophyte of rubber trees. In an effort to understand the genetic basis of endophytism, we compared the genome contents of X. heveae and 36 other Ascomycota with diverse lifestyles and nutritional modes. We focused on genes that are known to be important...
The symbiosis between cnidarians (e.g., corals or sea anemones) and intracellular dinoflagellate algae of the genus Symbiodinium is of immense ecological importance. In particular, this symbiosis promotes the growth and survival of reef corals in nutrient-poor tropical waters; indeed, coral reefs could not exist without this symbiosis. However, our fundamental...
Adults and nymphs of a new genus and species of the family Macrochelidae are described from detritus cavities of the leafcutting ant, Atta texana. This new species is notable in having peritremes with no posterior loop, a series of small subterminal teeth on the fixed cheliceral digit rather than the...
The chlamydospore is a survival spore produced by 35 of the 75 described species of Phytophthora. Phytophthora ramorum Werres, de Cock & Man in't Veld, the causal agent of Sudden Oak Death (SOD), produces abundant chlamydospores in artificial culture and plant tissue. The chlamydospore is likely the most important survival...
The coniferous forests of the Pacific Northwest are
affected by a variety of endemic fungal root pathogens. Forest
disease surveys have noted the presence of two or more of
these root pathogens infecting the same stump or root, and it
has been suggested that these fungi may be interacting
synergistically....
The Pacific Northwest has become one of the nation’s premier sweet cherry,
Prunus avium, production areas. As production of sweet cherries has flourished in
Oregon and Washington, so has powdery mildew, caused by the fungus
Podosphaera clandestina, which infects both foliage and fruit causing severe
economic damage to growers. Sweet...
Natural dyes have been used to color textiles for centuries, but with the shift to mass production, the use of synthetic dyes has increased due to their lower cost and easy manufacturing volume. However, synthetic dyes (such as disperse blue dyes 106 and 124) have been reported to cause skin...
Nitula baltica sp. nov. and Cyathus dominicanus sp. nov. are described from Cenozoic Baltic and Dominican amber. These are the first fossil members of the Family Nidulariaceae and show that the basic characteristics of this group were already established some 40-50 million years ago.
A variety of soil properties have been proposed and tested as potential
indicators of soil quality. This study was conducted in an effort to produce a
standardized soil quality index for systems in Oregon. Soils in both forested and
agricultural systems were sampled in a wide variety of locations, climates,...
The Lecanoromycetes is the largest class of lichenized Fungi, and one of the most species-rich classes in the
kingdom. Here we provide a multigene phylogenetic synthesis (using three ribosomal RNA-coding and two
protein-coding genes) of the Lecanoromycetes based on 642 newly generated and 3329 publicly available
sequences representing 1139 taxa,...
Common ecological restoration treatments such as thinning trees and prescribed burning could result in changes to soil fungal communities and changes to the function of those communities. Ectomycorrhizal fungi are especially likely to be affected as they are symbionts on plant roots and exhibit host and niche preferences. Ectomycorrhizal fungi...
Fungi play critical roles in ecosystem processes and interact with plant communities in mutualistic, pathogenic, and commensal ways. Fungal communities are thought to be influenced by both associated tree communities and soil properties. However, the relative importance of the biotic and abiotic drivers of soil fungal community structure and diversity...
The vast majority of terrestrial plant species live in symbiosis with arbuscular mycorrhizal fungi (AMF). AMF and plants live in complex networks, with roots of individual plants hosting multiple AMF, and single AMF colonizing multiple plants concurrently. Through the exchange of resources, the two partners of this symbiosis can have...
Secondary metabolites (SMs) play an integral role in the life history of most fungal species. Fungal metabolomic studies provide insights into how fungi perform certain ecological functions, how they compete and interact with other organisms, and the breadth of fungal chemodiversity. Fungal SMs have also been utilized for a variety...
Total length and biomass of fungal mycelium in the soil of a young Douglas-fir stand in the central Oregon Coast Range were estimated over 27 months with the agar-film technique. In a second study, phenology and taxonomy of hypogeous (belowground) sporocarps were studied over 32 months in a nearby, young...
The cycloundecapeptide cyclosporin A (CsA) was first isolated from the insect-pathogenic fungus Tolypocladium inflatum for its antifungal activity and later developed as an immunosuppressant drug. However, the full biosynthetic mechanism of CsA remains unknown and has puzzled researchers for decades. In this study, the biosynthetic gene cluster is suggested to...
Grapevine Trunk Diseases (GTDs) are caused by a group of fungal pathogens that attack the xylem tissue of mature grapevines worldwide. In the past 30 years, their incidence has increased, both in emerging grape-producing regions, as well as those with an extended history of viticulture. In the same time span,...
The effects of fire on above-ground forest systems have been extensively studied. However, research on fire effects on belowground processes is lacking. While the soil microbiome is understood to be vital to conifer growth and regeneration, the complexity of soils means that research on the topic has largely been accomplished...
Treating durable, second-growth or plantation-grown material with supplemental chemicals could improve durability while enhancing the uniformity of the products. To test this hypothesis, the effect of two candidate biocide treatments on the durability of teak, redwood, and western redcedar was assessed in a ground proximity field test established in Hawaii....
The enlargement of 21 canopy gaps associated with the root pathogen Heterobasidion annosum (Fr.:Fr.)
Bref. (; Fomes annosus (Fr.) Karst.) in the mixed-conifer forest of Yosemite Valley was monitored between 1971 and
1998. Mean expanded gap area was 232 m2 (range 38–802 m2) in 1971 and 1455 m2 (range 150–4216...
Fungi are a large group of eukaryotes found in nearly all ecosystems. More than 250 fungal genomes have already been sequenced, greatly improving our understanding of fungal evolution, physiology, and development. However, for the Pezizomycetes, an early-diverging lineage of filamentous ascomycetes, there is so far only one genome available, namely...
Pyrenophora tritici-repentis, causal agent of tan spot of wheat, produces multiple
host-selective toxins (HSTs), including Ptr ToxA, encoded for by ToxA, Ptr ToxB,
encoded for by ToxB, and Ptr ToxC. Variable distribution of these three HSTs among
different isolates of P. tritici-repentis, both singularly and in all possible combinations,
defines...
The purpose of this study was to estimate the portion of an ectomycorrhizal (ECM) fungi root
community with a hypogeous fruiting habit. We used molecular methods (DNA sequence analysis of the
internally transcribed spacer [ITS] region of rDNA) to compare three viewpoints: ECM fungi on the roots in a
southern...
It has been hypothesized that horizontal gene/chromosome transfer and parasexual recombination following hyphal fusion between different strains may contribute to the emergence of wide genetic variability in plant pathogenic and other fungi. However, the significance of vegetative (heterokaryon) incompatibility responses, which commonly result in cell death, in preventing these processes...
Moisture intrusion in residential structures can lead to substantial fungal decay and this damage costs billions in repair/replacement costs. The extent of damage and the rate at which it occurs are primarily dependent on the wood moisture content and temperature in the structure. Determining the risk of decay for various...
Overexpression of the bacterio-opsin (bO) gene in tobacco had previously been shown to induce hypersensitiveresponse- like lesions, increase viral and bacterial disease resistance, and stimulate pathogenesis-related gene expression. To see if this gene enhanced resistance to fungal pathogens of poplar, we generated a total of 35 transgenic lines in two...
With the resurgence in the interest of using natural textile dyes, a solution must be found that will overcome the limitations of traditional natural dyes. This solution must also be safer for both humankind and the environment than are synthetic dyes. This study compares the colorfastness of commercially available synthetic...
Five solvents were used to resolubilize the fungal pigments of Chlorociboria aeruginosa and Scytalidium cuboideum, two common fungi used in the spalting of wood pieces. These solvents were tested as a replacement for dichloromethane in the pigment application process, via analysis of their ability to increase internal color coverage inside...
Wood-staining fungal pigments have potential uses as colorants for wood and textiles. Traditionally, organic solvents have been used as carriers for these pigments. However, other environmentally-friendly and more readily available carriers must be found. Natural oils have the potential to carry these pigments but have demonstrated color loss over relatively...
Douglas-fir provides social, economic, and ecological benefits in the Pacific Northwest (PNW). In addition to timber, forests support abundant plant and animal biodiversity and provide socioeconomic viability for many rural communities. Products derived from Douglas-fir account for approximately 17% of the U.S. lumber output with an estimated value of $1.9...
The internalization of some oomycete and fungal pathogen effectors into host plant cells has been reported to be blocked by proteins that bind to the effectors' cell entry receptor, phosphatidylinositol-3-phosphate (PI3P). This finding suggested a novel strategy for disease control by engineering plants to secrete PI3P-binding proteins. In this study,...
This thesis describes an investigation of the natural products chemistry of two fungal species of the genus Tolypocladium. Natural products are small organic molecules that are considered non-essential for cell growth and reproduction, and thus part of secondary metabolism. Chemical profiling of these secondary metabolites using a combination of high-performance...
Caenorhabditis elegans is arguably the best understood animal on the planet.
Used for over 50 years to study development, we have a vast amount of knowledge of
the inner workings of this worm. Our knowledge is incomplete, however, without
placing this organism in its evolutionary and ecological context. In this...
Tan spot of wheat is an economically significant disease caused by the fungal pathogen, Pyrenophora tritici-repentis. Certain races of the fungus secrete Ptr ToxA (ToxA), a 13.2 kDa proteinaceous host-selective toxin that is responsible and sufficient to cause disease in susceptible wheat varieties. Disease symptoms develop only when the ToxA...
Biodiversity losses are occurring worldwide due to a combination of stressors. For example, by one estimate, 40% of amphibian species are vulnerable to extinction, and disease is one threat to amphibian populations. The emerging infectious disease chytridiomycosis, caused by the aquatic fungus Batrachochytrium dendrobatidis (Bd), is a contributor to amphibian...
The effects of scald epidemics, induced by Rhynchosporium secalis
(Oud.) Davis, on the yield and quality of winter malting barley have not been
reported. The principal objective of this investigation was to assess yield and
quality losses in resistant and susceptible winter barley genotypes in diverse
environments of the Pacific...
Protocylindrocorpus brasiliensis n. sp. (Diplogastroidea: Cylindrocorporidae) associated with the ambrosia beetle, Euplatypus parallelus (F.)(Coleoptera: Curculionidae: Platypodinae) in Para rubber trees (Hevea brasiliensis). Nematropica 00-00.
Protocylindrocorpus brasiliensis n. sp. (Diplogastroidea: Cylindrocorporidae) is described from reproductive stages removed from galleries of the ambrosia beetle, Euplatypus parallelus (F.)(Coleoptera: Curculionidae: Platypodinae) in Para rubber...
A new nematode, Anomalomermis ephemerophagis n. g., n. sp. (Nematoda: Mermithidae) is described from the mayfly Ephemerella maculata Traver, 1934 (Ephermeroptera: Ephermerellidae) in California. The new species is characterized by 6 cephalic papillae and 4 additional disk papillae located on the head between the cephalic papillae and stoma. Additional diagnostic...
Disease dilution (reduced disease prevalence with increasing biodiversity) has been described for
many different pathogens. Although the mechanisms causing this phenomenon remain unclear,
the disassembly of communities to predictable subsets of species, which can be caused by
changing climate, land use, or invasive species, underlie one important hypothesis. In this...
Background: Corals are capable of launching diverse immune defenses at the site of direct contact with pathogens, but the molecular mechanisms of this activity and the colony-wide effects of such stressors remain poorly understood. Here we compared gene expression profiles in eight healthy Acropora hyacinthus colonies against eight colonies exhibiting...
Invasive species can alter the succession of ecological communities because they are
often adapted to the disturbed conditions that initiate succession. The extent to which this
occurs may depend on how widely they are distributed across environmental gradients and
how long they persist over the course of succession. We focus...
Phytophthora vignae, causal agent of stem and root
rot of cowpea (Vigna unguiculata), was reported for the
first time in Sri Lanka. The pathogen was found in cowpea
field soils from 3 of 5 geographic regions sampled. Only
one site however, had plants exhibiting disease symptoms.
Of the eight cowpea...
Grape phylloxera, Daktulosphaira vitifoliae (Fitch) (Homoptera: Phylloxeridae), is an aphidlike insect that feeds aggressively on grape roots. Phylloxera is native to the eastern and southeastern United States, where native American grape species coevolved with the insect.
The rapid expansion of western juniper into neighboring plant communities during the past 130 years has caused considerable concern because of increased soil erosion, reduced stream
flows; reduced forage production; altered wildlife habitat; changes in plant community composition, structure, and biodiversity; and the replacement of mesic and semi-arid plant communities...
• Premise of study: In the mixed evergreen forests in the western United States, Arbutus menziesii is able to quickly resprout following disturbance and, as such, act as a nurse tree during forest regeneration. The mechanism for this nurse tree effect has frequently been ascribed to mycorrhizal fungi, but no...
Emerging infectious diseases are increasing globally and are a threat to human, wildlife, and ecosystem health. The emerging fungal pathogen, Batrachochytrium dendrobatidis (Bd), or amphibian chytrid fungus, is associated with worldwide amphibian population declines and extinctions. Bd has been found on every continent where amphibians exist and has been documented...
Foliar fungi – pathogens, endophytes, epiphytes – form taxonomically diverse communities that affect plant health and productivity. The composition of foliar fungal communities is variable at spatial scales both small (e.g., individual plants) and large (e.g., continents). However, few studies have focused on how environmental factors and host plant traits...
Swiss needle cast (SNC) is a fungal disease of Douglas-fir
(Pseudotsuga menziesii) that has recently become prevalent
in coastal areas of the Pacific Northwest. We used growth
measurements and stable isotopes of carbon and oxygen in
tree-rings of Douglas-fir and a non-susceptible reference
species (western hemlock, Tsuga heterophylla) to evaluate...
Western Oregon is home to native Rhododendron species and is the center for cultivated
Rhododendron production in the United States. These Rhododendron spp. are known to
be infected with fungal endophytes. However, the community structure of these
endophytes in native and cultivated Rhododendron is poorly understood. Our study
targeted the...
The effects of natural preconditioning (source wood), wood species, and previous
exposure of wood to two types of fungi on the feeding rates and protozoa survival in the
Pacific dampwood termite Zootermopsis angusticollis (Isoptera: Termospidae) were
examined under laboratory conditions. Termites were exposed to four wood species that
had been...
Small-mammal community composition, microhabitat selection, and
dispersal of mycorrhizal fungal spores were studied in southwestern
Oregon. Sampled habitats exhibited structural variation resulting
from silvicultural practices.
In 1981, the effect of clearcut treatment on these phenomena was
evaluated. In 1982, the effect of forest structure was studied.
Discriminant function analysis (DFA)...
Rapid rates of biodiversity loss have supported the notion that Earth is experiencing a sixth major extinction event. The causes of worldwide biodiversity loss are multifaceted and context dependent. One of the most prominent groups experiencing population declines and extinctions are amphibians. Several pathogens and their associated diseases are especially...
Treating styroblock containers in hot water (68°C) with a very dilute bleach and detergent solution effectively reduced populations of Fusarium and Cylindrocarpon spp., two potential root pathogens of containerized conifer seedlings. However, the treatment did not significantly reduce levels of Phoma (another potential pathogen) nor saprophytic Penicillium and Alternaria spp....
Commercial filbert orchards throughout the Willamette Valley
were surveyed for natural enemies of the filbert aphid, Myzocallis
coryli (Goetze). A large number of predaceous insects were found to
prey upon M. coryli, particularly members of the families
Coccinellidae, Miridae, Chrysopidae, Hemerobiidae, and Syrphidae.
Also, a parasitic Hymenopteran (Mesidiopsis sp.) and...
Species declines and extinctions have been recorded across taxa as evidence of an ongoing global biodiversity crisis. Amphibians are at the forefront of these declines with nearly one third of amphibian species estimated to be at risk of extinction. While many factors contribute to population declines and extinctions, the role...
Mutation of repetitive DNA by repeat-induced point mutation (RIP) is a process that occurs in many filamentous fungi of the Ascomycota during the sexual cycle. Concurrently, direct DNA repeats are often deleted by homologous recombination at high frequency during the sexual cycle. Thus, the processes of RIP and deletion compete...
The root disease fungus Inonotus tomentosus, common in the old
growth boreal forests of British Columbia, poses a threat to the
health of second growth forests established on sites with a previous
history of root disease. Colonized stumps occur in groups of 1 to 6;
the groups are clumped within...
Earth is experiencing unprecedented biodiversity loss. Amphibians are at the forefront of this biodiversity loss, with species declines estimated to be more severe than those of birds and mammals. Amphibian population declines and extinctions are driven by a number of factors including climate change, habitat destruction, contaminants and disease but...
Food habits and biology of five species of Pleocoma larvae were
studied at a dozen forested sites in western Oregon between May 1960
and December 1961.
First instar Pleocoma hatch in late summer and moult to second
instars in early fall. Second and subsequent instars moult annually
between mid-summer and...