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Cytological And Molecular Analyses Of The Ns Genome In Russian Wildrye, Psathyrostachys Juncea (Fisch.), Junzhi Wei

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Russian wildrye (Psathyrostachys juncea Fisch. 2n=2x=14, NsNs) is an important forage grass and a potentially useful germplasm in wheat improvement. A standard C-banding karyotype of Ps. juncea has been developed based on the C-bands of chromosomes in geographically diverse materials. Although there are C-banding polymorph isms, the seven pairs of chromosomes can be distinguished from each other according to their basic banding patterns. Based on C-banded karyotype, one deletion-translocation heterozygote, four primary trisomies, one double-deletion trisomic, and two tertiary trisomies were identified. These cytogenetic stocks will be useful in genetic studies of Russian wildrye.

Genetic variations in Russian wildrye were …

Winter Habitat Selection By American Marten (Martes Americana) In Newfoundland: Why Old Growth?, Gary S. Drew

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although the American marten (Martes americana) generally is recognized as an obligate late-seral species, the factors dictating this association are poorly understood. Martens were studied in Newfoundland, Yellowstone National Park, and in a captive setting. As expected, use of habitat types was not proportional to availability P < 0.001). Defoliated and late-seral conifer stands were used more than expected, while all other types indicated expected or less than expected use. Habitat selection by martens was detectable at spatial scales greater than 80 m (P < 0.001).

Newfoundland martens were radio-collared and monitored for diet activity during the winters of 1990 and 1991. A regression of the percent active fixes on temperature had a negative slope (b = -4.45, P = 0.084, n = 12), indicating that martens did not minimize their exposure to low temperatures. A log-linear model suggested …

Competitive Interactions Between Two Closely Related Rhizomatous And Caespitose Perennial Grasses Under Varying Conditions, L. David Humphrey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Biomass, tiller numbers, flowering, and genet survival were accessed for the rhizomatous Elymus lanceolatus ssp. lanceolatus and caespitose E. l. ssp. wawawaiensis growing in mixtures with a range of densities of each taxon. Models of aboveground biomass of each taxon as a function of mixed densities were used to calculate competition indices. Tiller numbers and biomass of ssp. lanceolatus were higher than those of the caespitose taxon in the first year, but declined in the second year, while biomass and tiller numbers of ssp. wawawaiensis changed little. All tillers of ssp. wawawaiensis emerged in autumn; tillers of ssp. …

Using Gis To Analyze The Precipitation Regime Of The Great Smoky Mountains National Park, Tn/Nc, Thomas Bryan Coffey

Masters Theses

Studies or research conducted in remote areas of the Great Smoky Mountains National Park (GSMNP) involving the use of precipitation data, have often resolved to utilizing the precipitation data from weather stations located in more easily accessible areas or from nearby towns and cities. This study was conducted to determine an accurate annual average precipitation value for the GSMNP and to develop an average annual precipitation database (coverage) for the park as a whole. Precipitation data from 51 weather stations in and around the GSMNP were placed into the geographic information system (GIS), ARC/INFO, and three methods were implemented to …

Identification Of Dna Markers In Triticum Aestivum-Aegilops Caudata Additions Lines By Randomly Amplified Polymorphic Dna (Rapd) Technology, Ling Wei

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this study was to identify DNA markers for each of six added C-genome chromosomes in Triticum aestivum L. cv. 'Alceso'-Aegilops caudata L. addition lines using the randomly amplified polymorphic DNA (RAPD) technique. DNA from Ae. caudata, T. aestivum, amphiploid of T. aestivum X Ae. caudata, and six disomic addition lines of wheat having a pair of Ae. caudata chromosomes was used as the template for the amplification of RAPD markers with a total of 58 random 10-mer oligonucleotide primers. Two primers, OPC-08 and OPJ-16, produced one intense band each from the amphiploid of …

Effect Of Light Intensity And Temperature On Light-Avoiding Leaf Movements In Two Phaseolus Species, Douglas Bielenberg

Presidential Scholars Theses (1990 – 2006)

It was the purpose of this experiment to determine the relationship between the factors of pulvinus temperature and light intensity in their role as factors that affect paraheliotropism. We also examined the differences in these relationships in two species adapted to different environments. The two species used were: Phaseolus vulgaris (common bean), a high yielding species which is grown in mesic climates, and P. acutifolius (tepary bean), an arid land bean which tolerates high temperatures and drought.

Lichen Use By Larval Leucochrysa Pavida (Neuroptera:Chrysopidae), Penni Jo Wilson

Masters Theses

Leucochrysa pavida is a species of green lacewing (Neuroptera:Chrysopidae) that uses lichen fragments to build a larval debris "packet." The "packet" is eventually used to form a cocoon used during pupation. Only minute lichen fragments are harvested for formation of the packets which makes identification of the actual lichens utilized difficult using morphological characteristics. For this reason, thin-layer chromatography was employed. The thin-layer chromatographic process identifies acetone-soluble lichen chemicals that are formed in lichen thalli. By comparing the chemistry of lichen communities at Tower Rock Recreation Area in Hardin County, Illinois, with the chemicals identified during thin-layer chromatography of larval …

Studies On Processes Controlling The Input Of Agricultural Chemicals In Groundwater To Surface Waters, Edward Laurence Libelo

Dissertations, Theses, and Masters Projects

This dissertation describes several studies of groundwater quality, the fate and transport of nutrients and atrazine in groundwater systems and physical processes at the sediment-water interface which impact on groundwater discharge. Groundwater monitoring wells were installed at the Goodwins Island and Catlett Island NERRS sites in Virginia and agricultural, suburban and forest land use sites in the York and James River Basins. Groundwater was analyzed for nutrients, pH, salinity and trace organics. Shoreline land use, associated nutrient loading and an estimate of total groundwater flux suggest that groundwater contributes up to 30% of the total nitrogen input to the Chesapeake …

Proline Concentration As An Indicator Of The Level Of Salt Tolerance, Philomena Y. Rosalie

Theses : Honours

Each year approximately 20 million hectares of land become affected by increasing salinity. Salt tolerant plants are being used to rehabilitate salt affected areas. Plants use a variety of mechanisms to adapt to salt in their environments. Glycophytes tolerate low to moderate levels of salt while halophytes can tolerate very high salt levels. Many basic physiological attributes have been suggested as important components of a salt tolerant phenotype. These include, influx and/or efflux of ions across plasma membrane and the tonoplast, modification of membrane composition and synthesis of compatible solutes such as soluble carbohydrates, glycine betaines and proline. The project …

Effects Of Ozone During Soybean Seed Development On Seed Vigor, Karen A. Gerlach

Masters Theses

Soybean (Glycine max L. Merr. cv 'Essex', 'Forrest' and 'Clark') seed were obtained from Dr. Mulchi of the University of Maryland. Seed from 1989 and 1990 were from plants which were exposed to three regimes of ozone during seed development including charcoal-filtered (no ozone), non-filtered (ambient ozone), and non-filtered + 40 n11^-1 O₃. Seed from 1994 were developed with four pollutant regimes of ozone during seed development including charcoal-filtered (no ozone), non-filtered (ambient ozone), non-filtered + 40 n11^-1, and non-filtered + 500 u11^-1 CO₂. The objective of this study was to assess …

Comparison Of Sweet Corn Vigor With Ions And Sugars In Seed Leachate Of Five Isolene Pairs With Two Endosperm Types, Marla K. Faver

Masters Theses

Supersweet corn contains more sugar and less starch than traditional sweet corn which increases the sweetness of the kernel. Supersweet corn has increased in consumer popularity due to its sweeter flavor and ability to retain this sweeter flavor longer than traditional sweet corn. Two sweet corn (Zea mays L. var. rugosa) endosperm types (traditional and shrunken-2) are popular with consumers. The problem growers face with supersweet cultivars (shrunken-2) is poor seed vigor as shown by low field emergence and non-uniform stands.

Field emergence of plants was compared to laboratory germination for 5 sweet corn isoline pairs (genetically identical except for …

The Optimisation Of Nitrogen Content For Micropropagation Of Eucalyptus Marginata, Andrew James Woodward

Theses : Honours

The use of eucalypts for plantation timber and pulp is becoming increasingly important, as are eucalypts that are resistant to disease and insect herbivory. Where clones with desirable traits have been selected, it is important that these genotypes are preserved. Micropropagation of some eucalypts, and Eucalyptus marginata in particular, can be difficult possibly due to the currently used basal medium of Murashige and Skoog (M&S)(I 962). By examining the nitrogen utilisation and the effects of medium pH of this species, it may be possible to improve general micropropagation protocol. Six clones of the species E. marginata were obtained as shoot …

The Vascular Flora Of The Carrotoman River Watershed, Lancaster County, Virginia, Troy W. Weldy

Dissertations, Theses, and Masters Projects

No abstract provided.

An Ultra Structural Study Of Sporogenesis, Vegatative Morphology, And Host-Parasite Interactions In Choreonema Thuretii (Corallinales, Rhodophyta), Elizabeth Anne Lapointe

Dissertations, Theses, and Masters Projects

No abstract provided.

Phylogenetic Implications Of Sporogenesis Ultrastructure In The Genus Bossiella (Corallinales, Rhodophyta), Kimberly Joy Karnas

Dissertations, Theses, and Masters Projects

No abstract provided.