Biology Commons^™

Historical Notes On Collections And Taxonomy Of Penstemon Haydenii S. Wats. (Blowout Penstemon), Nebraska's Only Endemic Plant Species, David M. Sutherland

Biology Faculty Publications

Penstemon haydenii was originally described in 1891 by Sereno Watson and was named for its first collector, the geologist and explorer Ferdinand V. Hayden, who probably collected it in the late summer of 1857 in the" Sand Hills of Loup Fork," Nebraska. The Hayden specimen which Watson saw in the Gray Herbarium at Harvard University had evidently been labeled with an incorrect location. Watson did not base his description on that early specimen but upon a more complete specimen, also in the Gray Herbarium, taken by Herbert J. Webber in Thomas County in 1891; so the Webber specimen, not the …

The Isolation And Identification Of Filamentous Fungi From Distribution Systems, Ground Water, Cisterns And Hemodialysis Water, Tammy J. Liles

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Arts and Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Tammy J. Liles on August 18, 1987.

The Role Of Iron Nutrition In Regulating Patterns Of Photosynthesis And Nitrogen Metabolism In The Green Alga Scenedesmus Quadricauda, Dennis Raymond Ades

Dissertations and Theses

The influence of iron nutrition on patterns of photosynthetic behavior, nitrogen metabolism, and fixed-carbon allocation is reported for a common freshwater green alga. Cultures of Scenedesmus quadricauda were grown in Fraquil medium in which iron concentrations ranged from 1.0 μM to 0.01 μM (log 10-6 to 10-8 M, respectively). Carbon 14 and nitrogen uptake experiments were conducted at photosynthetically saturating and subsaturating photon flux densities.

Physiological Changes In Portulacaria Afra (L.) Jacq. During A Summer Drought And Rewatering, Lonnie J. Guralnick, Irwin P. Ting

Arts & Sciences Faculty Publications

The changes of titratable acidity, enzyme activity, water status, and pigment composition were studied in Portulacaria afra (L.) Jacq. during a normal summer drought and rewatering. Two groups of plants were grown outside under a clear plastic canopy with water stress initiated at 2-week intervals in May 1986. Drought resulted in a linear decrease of fresh weight for 80 days and there was no further fresh weight change for the next 65 days. Nocturnal CO(2) uptake remained measurable for 83 days. Cessation of exogenous CO(2) uptake corresponded to the point where the pressure potential (Psi(p)) became zero. Ribulose-1, 5-bisphosphate (RuBP) …

New And Corrected Records Of The Flora Of Nebraska, Steven B. Rolfsmeier, Robert B. Kaul, David M. Sutherland

Biology Faculty Publications

New distributional data are provided for 27 species of vascular plants in Nebraska, eight newly recorded as growing wild in the State. The record of one species previously attributed to the State is shown to be based upon misidentified specimens, the range of another is shown to be much more restricted in Nebraska than previously reported, and nomenclature is corrected for two species.

Reproductive Structure Of Lithocarpus Sensu Lato (Fagaceae): Cymules And Fruits, Robert B. Kaul

School of Biological Sciences: Faculty Publications

Seventy-three species were examined for structural and developmental details of the cymules and fruits. The cymules bear one to seven or more flowers and are subtended by one to nine or more bracteoles. Generally, the number of flowers and bracteoles in the pistillate cymules is the same or less than in the staminate ones. Some of the latter have an inner set of bracteoles that could be homologous to the pistillate cupule. Scales are present at anthesis on the cupules of all species examined, but in some species they fail to enlarge, are torn or disintegrate, or fall away as …

Early Successional Plant Communities On An Abandoned Strip Mine In Butler County, Kentucky, Ralph Reiss

Masters Theses & Specialist Projects

Plant growth and development during the growing season of 1985 were examined on a strip mine located in Butler County, Kentucky, abandoned in 1963. Analysis included field plot measures of the frequency, density, and percent cover of the established plant species and determination of biomass accumulation during the 1985 year. Experimental subplots were established in both field and laboratory settings and the growth of the herbaceous colonizers compared under natural and programmed growth chamber conditions. Microclimatic measures of temperature and solar insolation were conducted in the field along with soil texture and pH measures. Results indicate that in the early …

Hormonal Control Of Phloem Loading In Celery (Apium Graveolens L.), Mark Watts

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Previous research has indicated that phloem loading may be regulated by plant growth regulators. This conclusion, however, is based on circumstantial evidence in that previous experiments implemented complex tissue such as leaf discs or petioles to simulate phloem loading. Celery is a favorable system to measure phloem loading because it utilizes pure vascular tissue and/or isolated phloem tissue. Pure phloem tissue has not been used to date in phloem loading research.

It was demonstrated that the plant growth regulators gibberellic acid (GA₃) and indole acetic acid (IAA) caused an enhancement of sucrose-loading in vascular bundles and in isolated …

Morphological Aspects Of Seedling Establishment In Four Temperate Region Phorandendron Spp., Beverlee M. Ruhland

Dissertations and Theses

Four species of Phoradendron were examined for seedling morphology: P. bolleanum subsp. densum (on Juniperus), P. californicum (on Prosopis), P. juniperinum subsp. juniperinum (on Juniperus, P. villosum subsp. villosum (on Quercus). The main species used in the study was P. juniperinum, using the other species for comparison. The initial shoot(s) of P. juniperinum may develop from the epicotyl of the developing seedling, from adventitious buds which arise from a cushion of tissue, termed the haustorial cushion, formed beneath the holdfast, or from both positions. When shoots arise only from adventitious buds the original seedling remains attached in a lateral position, …

Nebraska Plant Distribution, David M. Sutherland, Robert B. Kaul

Biology Faculty Publications

Distribution notes based on recent collections and herbarium work are provided for 46 Nebraska plant taxa, including 43 flowering plants, two ferns, and one liverwort. The list includes several plants that are new to the State and provides range extensions within the State for many others. Several previously- published distribution records believed to be erroneous are also discussed.

Evolution And Reproductive Biology Of Inflorescences In Lithocarpus, Castanopsis, Castanea, And Quercus (Fagaceae), Robert B. Kaul

School of Biological Sciences: Faculty Publications

Of Lithocarpus, Castanopsis, Castanea, and Quercus, only Lithocarpus frequently bears branched spikes suggestive of the primitive condition in the Fagaceae; the other genera sometimes have them in some individuals. Simple and branched spikes can occur on the same tree. Evolution of the simple spike is interpreted as the loss of branching capacity in the branched spikes. The Fagaceae show various transitional stages from perfect, entomophilous to imperfect, anemophilous flowers and from mixed-sex to unisexual spikes. Complete separation of staminate from pistillate function into separate spikes and catkins occurs only in Quercus, which is also the only …

The Isolation, Property Analysis And Determination Of In Planta Growth Ability Of Extracellular Polysaccharide Mutants Of Corynebacterium Michiganense Pv Insidiosum, Mary C. Paschke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Corynebacterium michiganense pv insidiosum, the organism responsible for bacterial wilt of alfalfa, produces an extracellular polysaccharide (EPS) that has been linked to its virulence. The EPS is composed of three different-sized molecules (components I, II and III). It has been demonstrated that this EPS accumulates in the vascular system of infected plants and causes disruption of the flow of water.

The importance of EPS to the survival and pathogenicity of C.m. pv insidiosumis not known. In order to begin assessing the value of EPS, mutant strains that are EPS-deficient were isolated after UV mutagenisis. Analysis by gel filtration …

The Role Of Copper In The Apparent Aluminum Toxicity Of Aquatic Systems, Kirk Thomas O'Reilly

Dissertations and Theses

The effect of variations in aluminum and copper concentrations on the growth rate and enzyme activity of the green alga Scenedesmus quadricauda was investigated. The goal was to determine which chemical species control the biological parameters. The computer program MINEQL (Westal et al 1976) was used to estimate chemical speciation. In the prevalence of both metals, algal growth rate and alkaline phosphatase activity could be correlated to cupric ion activity. The activity of isolated bacterial alkaline phosphatase was found to be a function of both total copper concentration and cupric ion activity. A model was developed to predicted the effects …

Extrafloral Nectaries On Plants In Communities Without Ants: Hawaii, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Since the Hawaiian Islands lack native ants, it was hypothesized that extrafloral nectaries, an ant-related mutualistic trait, should be lacking on native species. Presence of extrafloral nectaries (EFNs) on plants was determined by direct observation and related to vegetation structure and floral composition. Frequency of plants with EFNs was low by all possible comparisons. However, several endemic species had functional EFNs. The hypotheses to explain these anomalies are (1) phylogenetic inertia or (2) mutualism with some other organism than ants.

Benthic Diatom Community Dynamics In The Colorado River: Interactive Effects Of Periodic Dessication And Current Regime, Christopher Gerard Peterson

Publications (WR)

The response to periodic desiccation of periphyton communities developed in eddy environments or in areas exposed to variable, direct current was examined. Algal communities were incubated on clay tiles for between 2 and 12 weeks in the Colorado River, directly below Hoover Dam from October, 1983 - January, 1984. Mean daily discharge from the dam decreased over this period. To assess the influence of these discharge changes on community dynamics, samples collected over the first 12 weeks of the investigation were compared to samples of the same age collected over the final 8 weeks.

The small diatom taxon Achnahthes spp …

Ua66/6 Brigadoon Nature Preserve Survey Phase I, Wayne Mason, Jeff Jenkins, Kenneth Nicely, Herbert Shadowen

WKU Administration Documents

A preliminary report of an ongoing survey on the mammals, birds, vascular plants, and fungi that have been recorded at the Brigadoon Nature Preserve from November, 1983 - September, 1984.

An Evaluation Of Naturally Occurring Populations Of Magnolia Tripetala L. In Indiana, Kemuel S. Badger

All-Inclusive List of Electronic Theses and Dissertations

Magnolia tripetala L. occurs in Indiana as a disjunct from the Appalachian mountains populations. Currently, the known distribution of ~· tripetala in Indiana is confined to seven sites in Crawford County. The current status of ~· tripetala and the surrounding plant community was evaluated to aid in the future study, protection and management of this species, which is endangered in Indiana. Systematic random sampling of the tree stratum was done with belt transects. The sapling and seeding strata were sampled with subplots, placed along the belt transects. Permanent plots were established to enable future monitoring of what is currently prime …

Phenotypic Differences In Populations Of Euonymus Americanus L. From The Central United States & Autecological Studies Of This Species In A Deciduous Forest Of Kentucky, Paul Bayer

Masters Theses & Specialist Projects

The concentrations of sodium and potassium in the leaves of Euonymus americanus collected from a relict hardwood forest during a four month period showed a possible winter conditioning pattern. Seeds collected from this same relict stand would not germinate, even though they were subjected to a wide variety of germination experiments. Phenotypic differentiation in fully developed leaves was not found; however, differences related to the length of the growing season were noted. Autecological studies of Euonymus americanus should be continued to investigate the role of this plant in relict hardwood stands.

Source Of Inoculum, Yield And Quality Of Tomato As Affected By Leveillula Taurica, Wayne B. Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tomato transplant stock from southern Nevada served as a source of inoculum and developed disease symptoms of tomato powdery mildew approximately three weeks before Utah-grown transplants. Plants from Nevada and Utah were equally infected seven weeks after planting and no differences in severity or yield were detected at the end of the season due to rapid spread of the fungus. Tomato yields were reduced ca 40% in check plots when compared to plots treated with triadimefon, propiconazol or sulfur. The amount of sunburned fruit in check plots was three to four times greater than in plots where the disease was …

An Ultrastructural Study Of Transmitting Tissue Development In The Pistil Of Lilium Leucanthum, Stanley R. Gawlik

Biology Faculty/Staff Publications

A study of developing transmitting tissue of Lilium Leucanthum pistils was undertaken in order to correlate structure with function. Lining the stylar canal are stigmatoid cells which contain a secretory zone consisting of a labyrinth of wall ingrowths characteristic of transfer cells. The functional feature of the labyrinth is a high surface-to-volume ration that facilitates an intensive transmembrane flux of solutes. Stigmatoid cells in various stages of development and maturation have been investigated with the aid of electron and light optics in conjunction with cytochemical techniques. During the development of the secretory zone, vesicles, formed by hypersecretory dictyosomes, fuse with …

Vegetative Key To Grasses Of The Sand Hills Region Of Nebraska, David M. Sutherland

Biology Faculty Publications

All illustrated key is provided that will facilitate identification of grasses in the vegetative condition in the Sand Hills region of Nebraska. The key separates 97 species, varieties, and species groups and discusses or partially separates 14 additional taxa. It emphasizes characteristics that may be observed in the field with a hand lens and is illustrated with 109 camera lucida drawings.

Inflorescence Architecture And Evolution In The Fagaceae, Robert B. Kaul, Ernst C. Abbe

School of Biological Sciences: Faculty Publications

First paragraph:

Inflorescence architecture is receiving increasing attention with respect to its role in the life of plants, but much remains to be learned of its effects on pollination and dispersal biology (see Wyatt, 1982). Little is known of the biology of fagaceous inflorescences or of their relationships with the growth or the reproductive patterns of the trees. Most studies (Abbe, 1974; Macdonald, 1979; Fey & Endress, 1983) have concentrated on the nature of the flower clusters (often called dichasia or partial inflorescences) and cupules. Hjelmqvist (1948) and Soepadmo (1972) briefly reviewed the variety of inflorescences in the Fagaceae. Čelakovský …

Seasonal Shifts Of Photosynthesis In Portulacaria Afra (L.) Jacq., Lonnie J. Guralnick, Patricia A. Rorabaugh, Zac Hanscom

Arts & Sciences Faculty Publications

Portulacaria afra (L.) Jacq., a perennial facultative Crassulacean acid metabolism (CAM) species, was studied under natural photoperiods and temperatures in San Diego, California. The plants were irrigated every fourth day throughout the study period. Measurements of ¹⁴CO₂ uptake, stomatal resistance, and titratable acidity were made periodically from July 1981 through May 1982. P. afra maintained C₃ photosynthesis during the winter and the spring. Diurnal acid fluctuations were low and maximal ¹⁴CO₂ uptake occurred during the day. The day/night ratio of carbon uptake varied from 5 to 10 and indicated little nocturnal CO₂ uptake. CAM …

Radiological Monitoring Of Select Faunal Species Indigenous To Environs Of The Maxey Flats Shallow Land Burial Facility, Robert Bruce Burns

Morehead State Theses and Dissertations

A Thesis presented to the faculty of the School of Sciences and Mathematics at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Robert Bruce Burns on December 14, 1983.

The Effect Of Hurricane Allen On The Near-Shore Vegetation Of South Padre Island, Frank W. Judd, Sammie L. Sides

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

The effect of Hurricane Allen (Aug. 10, 1980) on the near-shore vegetation of South Padre Island was assessed by comparing data obtained in line transects before and after the hurricane. Eight species of plants were present in the Backshore Zone prior to the hurricane; after the hurricane, only three species were present and percent cover was only 11% of that before the hurricane. The foredunes of this zone were completely leveled and a belt of Sesuvium portulacastrum was obliterated. Conversely, plants of the taller Primary Dune Zone were not greatly disturbed by the hurricane. Numbers of species and percent cover …

The Combined Effect Of Cu And Zn On Selenastrum Capricornutum, Helmer Colonia-Roque

Dissertations and Theses

It has been demonstrated that the toxicity of heavy metals depends on their chemical speciation and can be related to their free ion activities, rather than the total metal concentrations. The objective of this study was to determine the effect of combined free ions of zinc and copper on the toxicity to the green alga Selenastrum capricornutum. This alga was grown in a defined medium, under controlled laboratory conditions, with a varying range of zinc and copper concentrations. The growth rate of the alga was inhibited at pZn = 5.93 or at pCu = 7.24. The results suggest that …

Plant Responses To Clinostating And Mechanical Stress: Growth And Flowering Responses, Chauncy Steed Harris

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plants rotated about a horizontal axis show certain growth responses. This research was designed to clarify which of the responses of clinostating are caused by gravity compensation and which are caused by mechanical stresses. Plants used were Xanthium strumarium L. (cocklebur) Chicago strain and Lycopersicon esculentum Mill. (tomato) cv. Rutgers. Six automated treatments that ran for five days were used to separate out the effects. Treatments were: 1) controls, 2) horizontal clinostat, 3) intermittent clinostat, 4) inversion (every 10 min), 5) invert and return, and 6) vertical rotation. Plant height and diameter changes were measured at ink dots with a …

The Effect Of Dwarf Mistletoe (Arceuthobium Americanum) Upon A Portion Of The Carbon Budget Of Lodgepole Pine (Pinus Contorta), Nancy Ellen Broshot

Dissertations and Theses

Arceuthobium americanum is a vascular plant which is parasitic upon Pinus contorta var. murrayana. Its documented effects include reductions in host growth, vigor and wood quality. The specific physiological changes that occur in the host are, for the most part, unknown.

In an attempt to understand the manner in which the mistletoe alters its host's carbon budget, a model is proposed which states that the host plant has priorities for carbon allocation. The model proposes that the parasite will access the host's carbon initially in terms of carbon intended for storage, next, in terms of carbon intended for growth, …

Occurrence Of Psilocybin/Psilocin In Pluteus Salicinus (Pluteaceae), Stephen G. Saupe

Biology Faculty Publications

No abstract provided.

Variation In Branch Growth Characteristics Of Pinus Contorta Infected With Arceuthobium Americanum, Lynn Anne Larsen

Dissertations and Theses

Arceuthobium americanum is a flowering plant which parasitizes Pinus contorta (Lodgepole pine). This study examined branch performance of P. contorta infected to varying degrees with A. americanum.