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Articles 1 - 30 of 51
Full-Text Articles in Botany
Factors Affecting Apothecia Production And Primary Infection By Monilinia Vaccinii-Corymbosi On Vaccinium Angustifolium, Ian Leonard
Electronic Theses and Dissertations
Mummy berry, caused by Monilinia vaccinii-corymbosi (MVC), is a prolific disease of Vaccinium angustifolium (wild blueberry) leading to decreased yield in wild blueberry fields throughout the Downeast (DE) and Midcoast (MC) regions of Maine (ME). This study aimed to identify factors affecting primary inoculum production and infection by MVC on wild blueberry, and what bud stages of wild blueberry are most susceptible to infection. Through common garden (CGE), field and incubation experiments conducted in 2021 and 2022, factors affecting carpogenic germination of MVC pseudosclerotia and relationships between susceptible wild blueberry buds and environmental factors were analyzed. The CGE conducted in …
A Sky Island Perspective: New England Alpine Plant Distributions Across The Region, Andrea Tirrell
A Sky Island Perspective: New England Alpine Plant Distributions Across The Region, Andrea Tirrell
Electronic Theses and Dissertations
Alpine ecosystems around the globe are at risk due to climate change, human disturbance, and habitat loss. New England alpine zones are small and fragmented, which could make them vulnerable to global change. However, the persistence of tundra relics throughout the Holocene suggests the persistence of these communities in microclimate refugia. Assessing the near-term vulnerability of alpine plant communities is challenged by a lack of standardized, repeat surveys and long-term monitoring data, which presents a challenge for the many agencies monitoring New England’s alpine zones. Island biogeography theory predicts that alpine species richness is a function of area, but this …
Distribution And Soil Characteristics Associated With The Neches River Rose-Mallow (Hibiscus Dasycalyx), Morgan E. Langlinais
Distribution And Soil Characteristics Associated With The Neches River Rose-Mallow (Hibiscus Dasycalyx), Morgan E. Langlinais
Electronic Theses and Dissertations
The Neches River rose-mallow, Hibiscus dasycalyx, is a rare herbaceous perennial endemic to East Texas. The threatened, obligate wetland species is currently at risk of being lost in the wild due to habitat loss, encroachment of nonnative and native plant species, and hybridization with two other Hibiscus congeners, Hibiscus laevis and Hibiscus moscheutos. Known locations of each of the three Hibiscus species were used to measure select soil characteristics and habitat variables associated with each of the rose-mallows. H. dasycalyx was concluded to be associated with more fertile soils and slightly more canopy coverage than H. laevis and …
Flora Of Doe Mountain Recreation Area, Johnson County, Tennessee, Benjamin Mccullough
Flora Of Doe Mountain Recreation Area, Johnson County, Tennessee, Benjamin Mccullough
Electronic Theses and Dissertations
A botanical inventory of Doe Mountain Recreation Area (DMRA) in northeastern Tennessee was conducted to help guide conservation-based management. A total of 484 species were found in DMRA, comprising 94 families, and 285 genera, 10 species listed in the state rare plant list, and 76 exotic species. Two species, Liatris virgata and Lycopodiella inundata, were new state records. Water in the Lycopodiella seep was an order of magnitude more acid than at other sites. An analysis of the wildland-urban interface showed that only 13% of the area was classified as uninhabited. The inventory-invasion index, introduced to quantify the relative …
Determining Effects Of Management Practices On Potato Early Dying And Soil Microbiome And Assessing Risk Of Fungicide Resistance In Verticillium Dahliae, Kedi Li
Electronic Theses and Dissertations
Potato early dying (PED) is a yield-constraining soilborne disease of potato, caused by Verticillium spp. with V. dahliae being the predominant causal agent. Since the pathogen inhabits soil for long periods, PED management aims to reduce the population of V. dahliae in soil. Benzovindiflupyr and azoxystrobin are effective chemicals and frequently used in the control of V. dahliae. In this study, field trials were conducted at Aroostook Farm, Presque Isle, ME in 2019 and 2020. Chemical and biological products have been studied for PED control, and fungicide resistance was also examined. To evaluate fungicide resistance, benzovindiflupyr was characterized on …
Assessing Plant And Lichen Diversity Using Reflectance Spectra, Lance Stasinski
Assessing Plant And Lichen Diversity Using Reflectance Spectra, Lance Stasinski
Electronic Theses and Dissertations
Biodiversity is changing and it is imperative that we continually assess it in order to preserve ecological services that we rely on. Spectral platforms are increasingly being used to assess biodiversity due to the fact that light reflected from an organism’s surface carries much of information about that organism. Despite the promise spectroscopy shows, two gaps in our knowledge remain. First, we do not know how well reflectance spectra can be used to estimate fine-scale diversity – intraspecific genetic and phenotypic diversity – that is fundamental to ecological and evolutionary processes. Second, spectral libraries, used to construct models to estimate …
Not All Pollinator Gardens Are Created Equally: Determining Factors Pertinent To Improving Pollinator Garden Effectiveness, Travis Watson
Not All Pollinator Gardens Are Created Equally: Determining Factors Pertinent To Improving Pollinator Garden Effectiveness, Travis Watson
Electronic Theses and Dissertations
Increasing evidence documenting the decline of insect populations, resulting from increasing human disturbances has resulted in efforts to establish pollinator gardens to provide additional resources for insect populations. However, our understanding of biotic and abiotic garden characteristics important for attracting and sustaining pollinator diversity is limited. Here, we evaluated 17 pollinator gardens to evaluate the effect of five biotic and three abiotic garden characteristics on pollinator species richness, abundance, and proportional representation of four pollinator functional groups. Plant species richness positively influenced pollinator richness and negatively influenced flower visitation. Bombus proportional abundance responded to several variables (distance to vegetation, plant …
Evaluating The Current Weed Community In Wild Blueberry Fields And Ipm Strategies For Spreading Dogbane (Apocynum Androsaemifolium), Anthony G. Ayers
Evaluating The Current Weed Community In Wild Blueberry Fields And Ipm Strategies For Spreading Dogbane (Apocynum Androsaemifolium), Anthony G. Ayers
Electronic Theses and Dissertations
Lowbush blueberry (Vaccinium angustifolium) is Maine’s third largest crop (USDA 2020 a). From 2017 – 2019 the three seasons yield average was 27,200 tons were harvested from 19,500 acres for a value of $22,468,000 (USDA 2020 c). Lowbush blueberries are managed on a two-year cycle. Every other year, lowbush blueberry fields are pruned to the ground either through the use of a tractor mounted flail mower or a prescribed burn (Yarborough 2009). Pruning is a necessary part of managing lowbush blueberries as the second-year growth produces the highest yield but steadily declines in subsequent years (Drummond et al. …
Characterizing Patterns In Texas Gulf Coast Beach Dune Plant Species Composition, Cody Foster
Characterizing Patterns In Texas Gulf Coast Beach Dune Plant Species Composition, Cody Foster
Electronic Theses and Dissertations
Regional vegetation patterns of Texas beach plant communities were analyzed using cluster analysis, ANOSIM, SIMPER, NMDS, and ISA for fives zones representing the foredune complex of twenty Gulf Coast beaches. ANOVA revealed that zones differ in terms of percent bare sand, percent vegetative cover, and species richness. Cluster Analysis, ANOSIM, and SIMPER results indicate that Texas beaches can be divided into northern and southern regions based on differences in species composition of plant communities. Indicator Species Analysis (ISA) indicates that northern beaches are characterized by the presence of Rayjacksonia phyllocephala, Ambrosia Strophostyles, Ambrosia psilostachya, and Panicum amarum …
Population Structure And Reproductive Biology Of Monilinia Vaccinii-Corymbosi (Reade) Honey In Lowbush Blueberry In Maine, Katherine A. Ashley
Population Structure And Reproductive Biology Of Monilinia Vaccinii-Corymbosi (Reade) Honey In Lowbush Blueberry In Maine, Katherine A. Ashley
Electronic Theses and Dissertations
Lowbush blueberry, Vaccinium angustifolium Aiton, is both an economically and culturally important crop in Maine, being one of the few endemic crops to North America. The fungus Monilinia vaccinii-corymbosi (Mvc) causes mummy berry disease and is a significant pathogen of both highbush (Vaccinium corymbosum) and lowbush blueberries. While impacts of this disease are not regularly documented, it is estimated that 30-50% of the yield in an unmanaged field can be lost because of Mvc. This disease is typically managed with fungicides or burning of the field during years when the field is pruned, however, the impacts to the …
Reverse Genetic Analysis Of Ehd1 For An Association Between Flowering Time And Seed Dormancy In Rice (Oryza Sativa L.), Yeter Karakoc
Reverse Genetic Analysis Of Ehd1 For An Association Between Flowering Time And Seed Dormancy In Rice (Oryza Sativa L.), Yeter Karakoc
Electronic Theses and Dissertations
This research aimed to understand the evolutionary mechanism of seed dormancy and flowering time and to provide basic knowledge for the manipulation of germination features in crop breeding. Flowering time and seed dormancy are two adaptive traits for flowering plants. Seed dormancy (SD) helps regulate the timing of germination to promote the survival of seed-bearing plants in adverse environments. Cereal crops and weedy/wild relatives, such as Asian cultivated rice and weedy rice (Oryza sativa L.), have weak and strong seed dormancy, respectively. Thus, weedy and cultivated rice has been used as a model system to investigate mechanisms of seed dormancy …
The Dispersal Pattern Of Thekopsora Minima In Wild Blueberry Determined By A Molecular Detection Method, Nghi Nguyen
The Dispersal Pattern Of Thekopsora Minima In Wild Blueberry Determined By A Molecular Detection Method, Nghi Nguyen
Electronic Theses and Dissertations
Blueberry rust caused by Thekopsora minima is a common disease in wild blueberry (Vaccinium angustifolium) and other Vaccinium genera. Understanding the spore dispersal pattern and disease cycle of fungal pathogens in wild blueberry is crucial for the development of a more efficient disease management program. Molecular assays for rapid detection and quantification of Thekopsora minima were developed to be incorporated with a spore trap sampling method and weather data collection to examine spore dispersal pattern and production in three different fields: Blueberry Hill Farm in Jonesboro, East Machias, and Spring Pond in Deblois, Maine, in three years 2014, …
Landscape Pattern And Wild Bee Communities In Maine, Brianne Du Clos
Landscape Pattern And Wild Bee Communities In Maine, Brianne Du Clos
Electronic Theses and Dissertations
Commercial production of lowbush blueberry (Vaccinium angustifolium Aiton) in Maine relies primarily on managed honeybee hives; however, naturally occurring wild bees are more efficient pollinators of the crop. Wild bees have short foraging distances and must nest near crop fields to provide pollination services. After crop bloom, the surrounding landscape must provide sufficient forage to maintain wild bee populations for the remainder of the growing season. Lowbush blueberries in Maine are produced in a mixed-use landscape with two distinct landscape contexts. Here, we document bee communities and habitat resources (nesting and floral) in power line rights-of-way and eight land …
Sunflower Pollinators In South Dakota: An Evaluation Of Species Composition, Abundance And Influence On Yield, Mackenzie Mattern
Sunflower Pollinators In South Dakota: An Evaluation Of Species Composition, Abundance And Influence On Yield, Mackenzie Mattern
Electronic Theses and Dissertations
In 2017 and 2018, South Dakota was the largest producer of sunflowers, Helianthus annuus L. (Asterales: Asteraceae) in the US, grossing approximately $178 million per year. In South Dakota, both confection and oilseed sunflower cultivars are grown. Despite breeding efforts to increase sunflower's ability to self-pollinate there is evidence that pollinator visitation results in increased sunflower yields. In addition, there is evidence that sunflower pollen is beneficial for pathogen resistance in various bee species, suggesting the importance of a mutualistic relationship between pollinators and sunflowers. In some areas, observed increases in sunflower yield is attributed to the presence of Apis …
Stoichiometric Homeostasis In Two Native And Two Invasive South Dakotan Grasses, Joshua Thonas Harvey
Stoichiometric Homeostasis In Two Native And Two Invasive South Dakotan Grasses, Joshua Thonas Harvey
Electronic Theses and Dissertations
Increased nutrient availability has been widely linked to the success of invasive plants, however a general mechanism explaining these observations is lacking. Stoichiometric homeostasis (H), which is the regulation of internal nutrient concentrations, has been used to explain changes in plant community diversity under alterations in nutrient availability. One hypothesis holds that plants with high regulation (larger H) decrease in abundance in nutrient enriched conditions but are stable in nutrient deficient and drought conditions, likely due to extensive root systems. Additionally, plants with low regulation (lower H) increase in abundance under nutrient enriched conditions but are sensitive to drought …
Climatic Range Filling Of North American Trees, Benjamin Seliger
Climatic Range Filling Of North American Trees, Benjamin Seliger
Electronic Theses and Dissertations
Understanding the degree to which species distributions are controlled by climate is crucial for forecasting biodiversity responses to climate change. Climatic equilibrium, when species are found in all places which are climatically suitable, is a fundamental assumption of species distribution models, but there is evidence in support of climate disequilibria in species ranges. Long-lived, sessile organisms such as trees may be especially vulnerable to being outpaced by climate change, and thus prone to disequilibrium. In this dissertation, I tested the degree to which North American trees are in equilibrium with their potential climatic ranges using the ‘range filling’ metric, which …
Flower Visitation In Relation To Pollen And Nectar Nutrition: Implications For Pollinator Habitat And Conservation, Megan E. Leach
Flower Visitation In Relation To Pollen And Nectar Nutrition: Implications For Pollinator Habitat And Conservation, Megan E. Leach
Electronic Theses and Dissertations
Pollination of both wild and crop plants is at a crossroads; honey bee populations are experiencing losses at a higher rate than ever before, and some native bee species are declining in abundance to the point of being listed as endangered species. A few examples of these threats include pesticide exposure, habitat loss, and climate change. In response to bee population declines, conservation efforts have been initiated to increase habitat quality for bees by planting pollinator reservoirs or gardens. Plants provide nutrition to bees in the form of pollen and nectar. Several studies have shown links between higher nutritional quality …
Soil Ecology Of The Exotic Dune Grass Leymus Arenarius., Matthew L. Reid
Soil Ecology Of The Exotic Dune Grass Leymus Arenarius., Matthew L. Reid
Electronic Theses and Dissertations
Exotic plants can alter the structure and function of native communities both above- and belowground, which is particularly important in primary successional sand dune ecosystems where plant-soil interactions are critical drivers of successional dynamics. In Great Lakes sand dunes, the native foundation grass Ammophila breviligulata dominates early in succession until an accumulation of detrimental soil organisms causes its die-back of the grasses. Die-back of this native foundation species can be slowed by mutualistic interactions between plants and mycorrhizal fungi. Changes to the plant community resulting from invasion, and subsequent effects on the soil community have the potential to disrupt the …
Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett
Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett
Electronic Theses and Dissertations
Lilium grayi (Gray’s Lily), a southern Appalachian endemic species, is threatened by a Lilium-specific fungal pathogen, Pseudocercosporella inconspicua. The disease is characterized by tan lesions that can cause early senescence, while also lowering seed production and viability. This project tested for P. inconspicua conidia and accessed health at nine locations. The disease was present and ubiquitous across the range of L. grayi. Through identification of P. inconspicua conidia in the field, L. superbum (Turk’s Cap Lily) was identified as an additional host, while L. michauxii (Michaux’s Lily) was disease-free. However, infection was inducible in both species. With …
Phenotypic Plasticity Of Native And Invasive Cool-Season Grasses In Response To Frequency Of Moisture Availability, Ming-Yu Stephens
Phenotypic Plasticity Of Native And Invasive Cool-Season Grasses In Response To Frequency Of Moisture Availability, Ming-Yu Stephens
Electronic Theses and Dissertations
Phenotypic plasticity, the ability of an individual to alter its growth in response to environmental conditions, is an attribute that is considered a likely invader attribute, as it provides the opportunity to expand its ecological niche breadth. Adaptive phenotypic plasticity can affect not only the ability to establish in a new environment, but also the ability to outperform the existing vegetation over time. Bromus inermis (smooth brome) and Poa pratensis (Kentucky bluegrass) are invasive species in tall- and mixed-grass prairie ecosystems. The objectives of this two-part study were to quantify the adaptive plasticity of biomass accumulation and tiller production in …
The Ecology And Evolution Of Rare, Soil Specialist Astragalus Plants In The Arid Western U.S., Joseph M. Statwick
The Ecology And Evolution Of Rare, Soil Specialist Astragalus Plants In The Arid Western U.S., Joseph M. Statwick
Electronic Theses and Dissertations
Organisms that specialize in uncommon habitats are, by their very nature, inherently uncommon. Specialization has its advantages, namely reduced competition and predation, but it also incurs costs. Specialists often have small population sizes, narrow ranges, and fragmented habitat, all of which engender negative consequences on an evolutionary timescale. Herein, I examine benefits and costs of specialization in selenium-hyperaccumulating plants in the genus Astragalus (Fabaceae). These plants are disproportionately likely to be rare and of conservation concern. Thus, I optimized germination pretreatments for Astragalus species such that seed loss can be minimized during ex situ cultivation, and found that physical scarification …
The Enhancement Of Wild Bees (Hymenoptera: Apoidea) For Pollination Security, Eric M. Venturini
The Enhancement Of Wild Bees (Hymenoptera: Apoidea) For Pollination Security, Eric M. Venturini
Electronic Theses and Dissertations
The acreage of pollinator-dependent crops continues to expand across the globe. Simultaneously, honey bee hives – an annually rented commodity that growers rely on – are more expensive every year and in some cases, scarce. In response, pollinator-dependent growers seek alternative pollinators. One approach is installing bee pasture on farms, a strategy that enables systems-based farmers to become in-situ farm-scale habitat managers. This thesis first presents a review of the literature on bee pasture plantings and provides a brief overview of some methods for assessing their impacts on the pollinator community. There are three major gaps in current bee pasture …
Classifying And Mapping Native Grasslands Of South Dakota's Northern Prairie Coteau And Characterizing Habitat For Dakota Skipper Conservation, Diane M. Narem
Classifying And Mapping Native Grasslands Of South Dakota's Northern Prairie Coteau And Characterizing Habitat For Dakota Skipper Conservation, Diane M. Narem
Electronic Theses and Dissertations
Native tallgrass prairie is becoming increasingly rare due to conversion and degradation, putting pressure on endemic prairie species such as the federally threatened Dakota skipper butterfly (Hesperia dacotae). To develop a conservation plan for the butterfly in South Dakota, accurate vegetation classification, mapping, and characterization are critical. The objectives of this study were to 1) rank prairie condition, 2) classify and map upland prairie, 3) characterize and compare vegetation at Dakota skipper inhabited and formerly inhabited sites, and 4) identify potential Dakota skipper habitat within a 225 mi2 (58,275 hectares) study area of the SD Prairie Coteau. Condition metrics were …
Cause And Impacts Of The Early Season Collapse Of Lilium Grayi (Gray’S Lily), On Roan Mountain, Tn/Nc, Russell J. Ingram
Cause And Impacts Of The Early Season Collapse Of Lilium Grayi (Gray’S Lily), On Roan Mountain, Tn/Nc, Russell J. Ingram
Electronic Theses and Dissertations
A population of the rare Southern Appalachian endemic species Lilium grayi, (Gray’s lily) Roan Mountain, TN/NC was monitored for 2 years to determine the cause and impact of an early season collapse. High concentrations of the Lilium spp. host-specific fungal phytopathogen, Pseudocercosporella inconspicua (G. Winter) U. Braun were associated with 19/20 symptomatic and 0/30 asymptomatic plants. Strength of the association between pathogen and disease and the replication of disease symptoms in 4/4 healthy hosts showed that P. inconspicua was the causal agent of the disease referred to as lily leaf spot. Disease had a severe impact on the population …
Survey Of The Native And Nonnative Vascular Plant Species Of Three Islands In Lake Winnipesaukee, New Hampshire, Mark Gardner Winkler
Survey Of The Native And Nonnative Vascular Plant Species Of Three Islands In Lake Winnipesaukee, New Hampshire, Mark Gardner Winkler
Electronic Theses and Dissertations
This study examined the long-term patterns in vascular plant composition on three islands in Lake Winnipesaukee, NH. It also tested the role of island biogeography in ecology as it analyzed the effectiveness of a land use plan implemented on the islands. Samplings were made on the islands in the summer of 2011 and were compared to earlier samplings in 1978, 1991, and 2001. The flora was observed and measured in 25 permanent plots that were established on the three islands in 1978. The understory flora was measured by presence and percent cover and the overstory was measured by frequency and …
Assessing The Biological Condition Of Maine Streams And Rivers Using Benthic Algal Communities, Thomas John Danielson
Assessing The Biological Condition Of Maine Streams And Rivers Using Benthic Algal Communities, Thomas John Danielson
Electronic Theses and Dissertations
The purpose of this study was to test and develop algal methods of evaluating the condition of Maine streams and rivers. The primary objective was to develop a statistical model to predict attainment of Maine's aquatic life criteria for water quality classes A, B, and C. I collected 298 samples of algae on rocks from 193 locations across the state. The major pattern in species composition related to conversion of forests to urban, residential, and agricultural land uses. I calculated preferred environmental conditions of 236 algal taxa for 1) concentrations of nitrogen, phosphorus, and dissolved ions in the water, 2) …
Reestablishing The Juneberry On The Fort Berthold Indian Reservation: Cultural, Horticultural, And Educational Connections, Kerry E. Hartman
Reestablishing The Juneberry On The Fort Berthold Indian Reservation: Cultural, Horticultural, And Educational Connections, Kerry E. Hartman
Electronic Theses and Dissertations
Tribal people of the Northern Great Plains have utilized plants for centuries. Amelanchier anifolia (Juneberries/Serviceberries) historically played an important part in the diet and culture of the Mandan, Hidatsa, and Arikara (MHA) Tribal Nations. Research conducted as part of this study into historical and contemporary uses of the Juneberry by MHA Tribal Members indicated extensive historical use and a high interest in Juneberry reestablishment for cultural, nutritional, and economic reasons. Previous research on Juneberries has investigated factors including state of dormancy, propagation method, transplant type, and mulch type. Another purpose of this study was to elucidate the impact of presence …
Evidence Of Ecological Speciation In Phacelia., Pamela Michele Glass
Evidence Of Ecological Speciation In Phacelia., Pamela Michele Glass
Electronic Theses and Dissertations
Phacelia purshii Buckley and P. fimbriata Micheaux are two species that are nearly morphologically indistinguishable. Seed germination experiments showed that the high elevation endemic, P. fimbriata requires lower temperatures to trigger germination. Following interspecific crosses, pollen tubes enter ovules and maternal tissue of the gynoecium matures but hybrid diploid and triploid organs fail to develop. DNA sequences from the ribosomal DNA internal transcribed region showed that P. fimbriata and P. purshii comprise a monophyletic clade but that P. fimbriata is more differentiated from related species. In contrast, P. purshii supported significantly higher levels of intraspecific polymorphism. Phacelia fimbriata and P. …
Myriophyllum Heterophyllum Michx. (Haloragaceae): Control And Vegetative Reproduction In Southwestern Maine, Jacolyn E. Bailey
Myriophyllum Heterophyllum Michx. (Haloragaceae): Control And Vegetative Reproduction In Southwestern Maine, Jacolyn E. Bailey
Electronic Theses and Dissertations
Native to the southeastern United States, variable-leaf watermilfoil (Myriophyllum heterophyllum) is an invasive species in the Northeast and has been documented in Maine lakes for twenty years. Variable-leaf watermilfoil is targeted by the Maine Department of Environmental Protection as a species of grave concern as it has aggressively colonized twenty-six water bodies in Maine. This aquatic invasive plant grows in dense mats and outcompetes native vegetation. It is causing both ecological and economic disruption to Maine's lakes and ponds. The plants clog boat motors and deter people from swimming and other water related activities. Allofragmentation and autofragmentation occur …
Systematics Of The Lobulomycetales, A New Order Within The Chytridiomycota, David Rabern Simmons
Systematics Of The Lobulomycetales, A New Order Within The Chytridiomycota, David Rabern Simmons
Electronic Theses and Dissertations
Based on molecular phylogenetic analyses, the polyphyletic order Chytridiales, one of the four orders in the Chytridiomycota, contains several well-supported clades. One species, Chytriomyces angularis, however, does not group within the robust clades of the Chytridiales or any other chytrid order. The light-level morphology and zoospore ultrastructure of this aquatic species also differ from those of the type species of the genus Chytriomyces. I amassed nine additional pure culture isolates of soil-inhabiting chytrids with morphologies or rDNA sequences similar to C. angularis, including two isolates of C. poculatus, and studied the molecular phylogeny of these ten …