Botany Commons^™

[Review Of The Book A Conspectus Of The North American Isoetaceae, By D. F. Brunton, J. T. Kartesz, M. Nishino, And P. C. Sokoloff]., Lytton John Musselman

Biological Sciences Faculty Publications

Isoetes (Isoetaceae; Lycopodiopsida; quillworts) constitutes a highly successful, cosmopolitan genus with over 200 species. Isoetes is derived from isos Greek for equal and eter for year, referring to the typically long persisting leaves of the sole genus in this ancient plant family. The leaves resemble a ‘quill-of-feather,’ hence the common name ‘Quillworts,’ wort, from old Germanic wurti, meaning plant. In large measure due to its simple form, inconspicuous appearance and negligible economic value, it represents one of the least studied and least collected of all North American genera. Isoetes constitutes a taxonomically enigmatic group with numerous polyploid species that arose …

Phytochemical And Nutritional Composition Of Vernonia Amygdalina: Antioxidant, Antidiabetic Efficacy, And Hematological Benefits, Hassan A. Adewuyi, Messiah Atapia, Emmanuel Ochonung, Sakariyau A. Waheed, Adebimpe H. Oluwatoyin, Chizoba V. Obunadike, Adeleye A. Edema, Samad Hussein, Usman A. Mohammed, Kevin L. Sebastine, Tolulope O. Jaiyeola

Chemistry & Biochemistry Faculty Publications

Vernonia amygdalina, a traditionally used medicinal plant, has been purported to possess health-promoting properties. The aim of this study is to investigate the phytochemical and nutritional composition of V. amygdalina, evaluate its antioxidant and antidiabetic efficacy, and assess its hematological benefits. Phytochemical screening, proximate analysis, antioxidant assays (DPPH, ABTS), antidiabetic evaluations in treptozotocin induced diabetic rats, and hematological assessments were conducted according to standard protocol. V. amygdalina exhibited a rich phytochemical profile, comprising flavonoids, phenolic acids, and terpenoids, alongside significant antioxidant activity (IC50 = 12.5 μg/mL) and complete source of protein. Proximate analysis revealed high protein (21.1%) and …

The Virginia Academy Of Science: A Scholarly Forum Over Decades For Students Of A Plant Ecologist, Stewart Ware

Virginia Journal of Science

As a newcomer to Virginia in 1968, I learned that annual meetings of the Virginia Academy of Science (VAS) were regarded as an excellent place for students to have their first experience giving a talk about their research to fellow scientists, and a place for faculty to get to know other Virginia scientists in their fields. Over the next four decades William and Mary students (undergraduate and graduate) and I were presenters or co-authors of 42 talks or posters at VAS annual meetings, 29 of them based on studies of plant ecology across Virginia. Two were talks by colleagues with …

A Taxonomic Revision Of The Genus Hydnora (Hydnoraceae), Sebastian A. Hatt, Chris J. Thorogood, J. F. Bolin, Lytton J. Musselman, Duncan D. Cameron, Olwen M. Grace

Biological Sciences Faculty Publications

A systematic monograph is presented for Hydnora (Hydnoraceae), a poorly known genus of holoparasitic plants distributed across Africa, Madagascar and southern Arabia. Species of Hydnora are characterised by their underground habit, unusual fleshy flowers and complete absence of leaves or photosynthetic tissue. This is the first detailed monograph of the genus Hydnora since 1935 and is informed by a comprehensive survey of herbarium specimens and literature. Detailed descriptions, full synonymy, distribution maps and discussion concerning confusable taxa are provided for each species, along with notes on ethnobotany, ecology and conservation. We place particular emphasis on the taxonomic value of osmophore …

Response Of Helenium Amarum To Environmental Stressors In The Presence Of Mycorrhizal Fungi And Its Role As A Pollinator Resource, Austin Jameson, Lisa Horth

Biological Sciences Faculty Publications

Globally, climate change is causing shifts in precipitation patterns. Shifting precipitation patterns can be a stressor for many species. One species that is experiencing such stress is Helenium amarum Raf (H. Rock). H. amarum, thrives in dry upland pastures and low-lying grassy and sandy habitat in the mid-Atlantic (USA), where it persists despite storm-driven standing water. Helenium amarum is a species that is toxic to livestock and has been found outside its native range. Temperature and light impacts on germination are already known, but the role of water availability and potential ameliorating effects of mycorrhizae during water stress have …

Taxonomic Status, Distribution And Conservation Of The Critically Endangered Plant Psychotria Angustata (Rubiaceae), Walter Simbaña, Alan Tye, Timothy J. Motley, Uno Eliasson

Biological Sciences Faculty Publications

Simbaña, W.; A. Tye, T. J. Motley & U. Eliasson. 2024. Taxonomic status, distribution and conservation of the Critically Endangered plant Psychotria angustata (Rubiaceae), endemic to Floreana Island, Galapagos. Darwiniana, nueva serie 12(2): 204-219.

Two species of Psychotria have been recognised in the Galapagos Islands, both understorey shrubs endemic to the archipelago: P. rufipes Hook.f. occurs on seven islands, including Floreana, while P. angustata Andersson is endemic to Floreana. Since their mid-19th century discovery, the taxonomic and ecological status of these species has been uncertain. To clarify this, we examined historical specimens and numerous recent collections of both species, and …

The Influences Of Disperser Behavior, Host Availability, And Environmental Conditions On The Distribution Of Oak Mistletoe [Phoradendron Leucarpum (Raf.) Reveal & M. C. Johnst.] In Eastern Virginia And North Carolina, Nicholas Pearce Flanders

Biological Sciences Theses & Dissertations

Mistletoes are shrubs that typically parasitize the branches of host trees and rely on avian frugivores for seed dispersal. Because mistletoes are restricted to a narrow range of suitable recruitment sites and avian frugivores are more visible than other guilds of seed dispersers, mistletoe-frugivore systems afford opportunities for assessing the roles of dispersal limitation and local environment in determining plant distribution. These mechanisms have been proposed as determinants of the observed association of oak mistletoe [Phoradendron leucarpum (Raf.) Reveal & M. C. Johnst.] with forested wetlands in eastern Virginia and North Carolina, USA. I tested the alternative hypothesis that …

Temporal Dynamics And Seed Dispersal In Plant-Frugivore Communities Of The Dominican Republic, Spencer Christian Schubert

Biological Sciences Theses & Dissertations

Plant-animal mutualisms are a foundational component of biodiversity in terrestrial ecosystems. Most tropical forest plants have adapted to produce fleshy fruits to attract frugivorous animals to disperse seeds. Interaction patterns among plant taxa and their seed dispersers are driven by a complex suite of factors involving their evolutionary history and environmental context, and the structure of these mutualistic networks are theoretically tied to their ecological function. I carried out a series of field studies to investigate the temporal dynamics of mutualistic interactions of plant and avian frugivore communities in the central Dominican Republic and how their characteristics affect seed dispersal …

Determinants Of Population Genetic Structure In Chamaecrista Fasciculata (Michx.) Greene (Fabaceae) In The Southeastern United States, Mahboubeh Hosseinalizadeh Nobarinezhad, Lisa E. Wallace

Biological Sciences Faculty Publications

Chamaecrista fasciculata is a widely distributed, phenotypically variable species in the eastern U.S. Whereas studies have demonstrated genetic structure and local adaptation in northern areas of its distribution, there has been no comparison of genetic variability among populations at the southern extent where phenotypic variation is more complex. We characterized genetic variation at 14 microsatellite loci for populations in Mississippi and Alabama and compared this to variation in a phenotypic trait, leaf pubescence. Geographic distance, climatic variables, and elevation were evaluated as factors to explain the observed patterns of genetic diversity. A significant amount of variation (19%) resided among populations, …

Influence Of Abiotic Drivers On 1-Year Seedling Survival Of Six Mangrove Species In Southeast Asia, Taylor M. Sloey, Kiah Eng Lim, Jared Moore, Jie Min Heng, Jia Min Heng, Michiel Van Breugel

Biological Sciences Faculty Publications

Establishment and survival of plant species in systems with dominant environmental drivers (i.e. factors that exert disproportionate control over species establishment and survival) is often thought to be dominated by one master variable. In forested wetlands such as mangroves, hydrology is typically considered the dominant limiting driver. At the same time, light is a major driver of plant community dynamics, with some of the best understood plant life-history tradeoffs related to fast growth under high-light conditions versus survival under low-light conditions. Yet light is given relatively limited consideration in mangrove research compared to other drivers. Understanding the relative importance of …

The Challenges Of Growing Orchids From Seeds For Conservation: An Assessment Of Asymbiotic Techniques, Devani Jolman, Martín I. Batalla, Alexis Hungerford, Pryce Norwood, Noah Tait, Lisa E. Wallace

Biological Sciences Faculty Publications

Lewis Knudson first successfully germinated orchid seeds asymbiotically on artificial medium in 1922. While many orchid species have since been grown asymbiotically, the tremendous variation in how species respond to artificial medium and growth conditions ex situ has also become apparent in the past century. In this study, we reviewed published journal articles on asymbiotic orchid seed germination to provide a summary of techniques used and to evaluate if these differ between terrestrial and epiphytic species, to identify areas where additional research is needed, and to evaluate whether asymbiotic germination could be used more often in ex situ conservation. We …

Fine-Scale Patterns Of Genetic Structure In The Host Plant Chamaecrista Fasciculata (Fabaceae) And Its Nodulating Rhizobia Symbionts, Mahboubeh Hosseinalizadeh Nobarinezhad, Lisa A. Wallace

Biological Sciences Faculty Publications

In natural plant populations, a fine-scale spatial genetic structure (SGS) can result from limited gene flow, selection pressures or spatial autocorrelation. However, limited gene flow is considered the predominant determinant in the establishment of SGS. With limited dispersal ability of bacterial cells in soil and host influence on their variety and abundance, spatial autocorrelation of bacterial communities associated with plants is expected. For this study, we collected genetic data from legume host plants, Chamaecrista fasciculata, their Bradyrhizobium symbionts and rhizosphere free-living bacteria at a small spatial scale to evaluate the extent to which symbiotic partners will have similar SGS …

Phenotypic Variation Of Partridge Pea (Chamaecrista Fasciculata) From Mississippi Persists In A Common Garden, Lisa E. Wallace, Mahboubeh Hosseinalizadeh-Nobarinezhad, Robert Coltharp

Biological Sciences Faculty Publications

Intraspecific phenotypic variation occurs for many different reasons and understanding its basis has applications in taxonomy, ecology, and evolution. Chamaecrista fasciculata (partridge pea) is a widely distributed species with much phenotypic variation and varied interactions with other species in communities where it grows. Botanists have often noted that phenotypic variation in some traits of this species increases from north to south in the eastern United States. In this study, we grew seeds collected from five Mississippi populations in a common greenhouse environment to determine if the observed variation in leaf and stem traits is maintained in this environment. Interpopulation variation …

Molecular Systematics Of Isoëtes (Isoëtaceae) In Eastern North America, Peter William Schafran

Biological Sciences Theses & Dissertations

Isoëtes (Isoëtaceae, Isoetales, Lycopodiophyta) is a cosmopolitan genus of aquatic lycophytes, occurring on every continent except Antarctica. Of approximately 200 total taxa, about half are in a clade of species mostly occurring in North and South America. Eastern North America accounts for 22% of global taxonomic diversity, containing 32 fertile taxa and 16 named hybrids. This taxonomic diversity is built upon relatively little morphological difference, and even combined with phylogenetic analysis using several nuclear and chloroplast DNA markers, no well-resolved systematic treatment within this clade exists.

This study aims to clarify the relationships between all species and subspecies of Isoëtes …

Low- Copy Nuclear Markers In Isoëtes (Isoëtaceae) Identified With Transcriptomes, Peter W. Schafran, Gabriel Johnson, W. Carl Taylor, Elizabeth A. Zimmer, Lytton J. Musselman

Biological Sciences Faculty Publications

PREMISE OF THE STUDY: Few genetic markers provide phylogenetic information in closely related species of Isoëtes (Isoëtaceae). We describe the development of primers for several putative low- copy nuclear markers to resolve the phylogeny of Isoëtes, particularly in the southeastern United States.

METHODS AND RESULTS: We identified regions of interest in Isoëtes transcriptomes based on low- copy genes in other plants. Primers were designed for these regions and tested with 16 taxa of Isoëtes and one species of Lycopodium. Parts of the pgiC, gapC, and IBR3 gene regions show phylogenetic signal within the North American and …

Interesting, Provocative, And Enigmatic: Morphological Observations On Southeastern Quillworts (Isoetes Isoetaceae, Lycopodiophyta, Rebecca D. Bray, Peter W. Schafran, Lytton J. Musselman

Biological Sciences Faculty Publications

The unique morphology of quillworts has received limited attention, and such studies have been limited to only a few species. Our extensive field work during the past two decades has revealed variation in the structures of the plant, including the rhizomorph, scales, phyllopodia, and abscission caps. Polarity of the axes of southeastern quillwort rhizomorphs varies from discoid (most species), to elongate, to upright with axis branching in several species. In species of intermittent streams, these branched rhizomorphs produce plantlets that break off in running water. Scales are tiny brown or black structures in alternating whorls with sporophylls (leaves). They are …

Population-Level Coordination Of Pigment Response In Individual Cyanobacterial Cells Under Altered Nitrogen Levels, Jaclyn Murton, Aparna Nagarajan, Amelia Y. Nguyen, Michelle Liberton, Harmony A. Hancock, Himadri B. Pakrasi, Jerilyn A. Timlin

Biological Sciences Faculty Publications

Cyanobacterial phycobilisome (PBS) pigment-protein complexes harvest light and transfer the energy to reaction centers. Previous ensemble studies have shown that cyanobacteria respond to changes in nutrient availability by modifying the structure of PBS complexes, but this process has not been visualized for individual pigments at the single-cell level due to spectral overlap. We characterized the response of four key photosynthetic pigments to nitrogen depletion and repletion at the subcellular level in individual, live Synechocystis sp. PCC 6803 cells using hyperspectral confocal fluorescence microscopy and multivariate image analysis. Our results revealed that PBS degradation and re-synthesis comprise a rapid response to …

Foraging Behavior Of Spring Bees And Their Agricultural Implications, Michael D. Gregory

Biological Sciences Theses & Dissertations

Colony Collapse Disorder has greatly reduced honey bee populations in the last decade. Native bees have been largely neglected in research, and their floral preferences may have agricultural implications because native bees ameliorate the demand to rely solely on non-native bees. In this work, pollinator visitation to flowers with manipulated ultraviolet floral patterns was monitored. Populations of wild showy golden-eye in Colorado, plus cultivar populations of black-eyed Susan and lawn populations of buttercups in Virginia were monitored for pollinator landings to compare preference for unmanipulated ultraviolet-absorptive floral guide preferences. Another number, a proxy for pollen load, was manipulated on strawberry …

Section Abstracts: Botany

Virginia Journal of Science

Abstracts of the Botany Section for the 94th Annual Virginia Academy of Science Meeting, May 18-20, 2016, at University of Mary Washington, Fredericksburg, VA.

Isoetes Mississippiensis: A New Quillwort From Mississippi, Usa, Peter W. Schafran, Steven W. Leonard, Rebecca D. Bray, W. Carl Taylor, Lytton John Musselman

Biological Sciences Faculty Publications

Isoetes mississippiensis S.W. Leonard, W.C. Taylor, L.J. Musselman and R.D. Bray (Isoetaceae, Lycopodiophyta) is a new species known from two sites along tributaries of the Pearl River in southern Mississippi. This species is distinguished from other species in the southeastern United States by a combination of character states including a basic diploid (2n=22) chromosome count, laevigate megaspores, and a narrow velum covering less than one-third of the adaxial sporangium wall.

Groundwater Thresholds For Root Decomposition And The Relation To Barrier Island Ecological State Changes, Matthew Lee Smith

Biological Sciences Theses & Dissertations

Barrier islands off the eastern shore of Virginia exhibit distinct habitats that abruptly transition between periodically brackish/freshwater marshes, wooded swales, and sparsely vegetated dunes. There is strong evidence that the plant communities and ecosystem processes occurring in each habitat are primarily influenced by nutrient availability and the distance between two of the three free surfaces: land and freshwater. At the Virginia Coast Reserve-Long Term Ecological Research Site in Virginia, USA, thresholds to belowground decomposition rates were identified by measuring decay of native roots and rhizomes at 32 elevations in relation to mean annual groundwater levels (-0.356 – 1.937 m). Negative …

Molecular Phylogeny Of The Genus Houstonia And Allies In Rubiaceae, Hunter Lee Shanks

Biological Sciences Theses & Dissertations

Houstonia (Rubiaceae) is a strictly North American genus of 24 species distributed from Mexico, throughout the United States, up to Canada. Houstonia has proven to be a taxonomically difficult genus since the Linnaean description of Houstonia and the related genera: Hedyotis and Oldenlandia in 1753. For over 250 years botanists have lumped and separated Houstonia from Hedyotis and Oldenlandia based on various morphological characters. The most recent circumscription of Houstonia (Terrell 1996) separated the genus into two subgenera with each subgenus containing two sections. Nuclear (ITS) and plastid (trnL-F, rps16) DNA sequences were used to build a molecular phylogeny depicting …

Section Abstracts: Botany

Virginia Journal of Science

Abstracts of the Botany Section for the 93rd Annual Meeting of the Virginia Academy of Science, May 21-23, 2015, James Madison University, Richmond, Virginia

Molecular Phylogenetics And Historical Biogeography Of The Tribe Chiococceae (Rubiaceae), Sushil Kumar Paudyal

Biological Sciences Theses & Dissertations

Chiococceae are a monophyletic assemblage of morphologically very diverse groups of plants ranging in habit from subshrubs to shrubs to tall trees exhibiting an astonishing variation in shapes and sizes of corolla, and kinds of fruits and seeds. They are primarily distributed in the Neotropics but also occur in the West Pacific islands; thus exhibiting amphi-Pacific tropical disjunction. This study addresses the phylogenetic relationships and biogeography of the Chiococceae using molecular DNA sequence data, and presents novel data on the tribal and generic delimitations, intergeneric relationships, and the origin and dispersal of this group.

In the most recent tribal delimitations …

Leonard O. Marrow

Virginia Journal of Science

Obituary for Leonard O. Marrow who died August 24, 2014

A Molecular Framework Phylogeny For Ptilotus (Amaranthaceae), Timothy A. Hammer

Biological Sciences Theses & Dissertations

Ptilotus (Amaranthaceae) is an Australian genus with over 100 species, most of which occur in arid Western Australia. Ptilotus has been a taxonomically difficult genus; despite rigorous morphological studies into the genus over many years, previous workers have found it difficult to delimit infrageneric groups due to inconsistent morphological variation. With the goal to establish a phylogenetic framework for the genus, 100 taxa were sampled, including 87 Ptilotus spp., and the ITS nrDNA and matK cpDNA were sequenced. The phylogeny was reconstructed using Bayesian, maximum likelihood and maximum parsimony analyses on separate and concatenated datasets. Morphological characters were assessed and …

Section Abstracts: Botany

Virginia Journal of Science

Abstracts of the Botany Section for the 92nd Annual Meeting of the Virginia Academy of Science, May 13-15, 2014, Virginia Commonwealth University, Richmond, Virginia

The Ethnobotany Of Pistacia Eurycarpa Yalt. In Iraqi-Kurdistan: Its Uses, Chemical Composition, And Anti-Biotic Activity Of Its Resin, Peter W. Schafran

Biological Sciences Theses & Dissertations

Pistacia eurycarpa Yalt. is a wild relative of pistachio (P. vera L.} that grows in the Zagros Mountains. For the Kurds who inhabit these mountains the tree has practical and cultural applications. All parts of this tree have a use, for structural materials, food, and medicine. While weII known in this region, the ethnobotany of P. eurycarpa is unknown in the outside world. I spent May and June of 2011 - 2013 in Sulaimani, Kurdistan, Iraq, collecting information on this tree. In this time period I was able to witness the harvest of unripe fruits. Information about the tree …

Section Abstracts: Botany

Virginia Journal of Science

Abstracts of the Botany Section for the 91st Annual Virginia Journal of Science Meeting, May 2013

The Effects Of 11 Yr Of Co2 Enrichment On Roots In A Florida Scrub-Oak Ecosystem, Frank Day, Rachel E. Schroeder, Daniel B. Stover, Alisha L. P. Brown, John R. Butnor, John Dilustro, Bruce A. Hungate, Paul Dijkstra, Benjamn D. Duval, Troy J. Seiler

Biological Sciences Faculty Publications

• Uncertainty surrounds belowground plant responses to rising atmospheric CO₂ because roots are difficult to measure, requiring frequent monitoring as a result of fine root dynamics and long-term monitoring as a result of sensitivity to resource availability.
• We report belowground plant responses of a scrub-oak ecosystem in Florida exposed to 11yr of elevated atmospheric CO₂ using open-top chambers. We measured fine root production, turnover and biomass using minirhizotrons, coarse root biomass using ground-penetrating radar and total root biomass using soil cores.
• Total root biomass was greater in elevated than in ambient plots, and the absolute difference was larger than …