Life Sciences Commons^™

Molecular Cloning And Characterization Of The Porcine Fto Promoter And Coding Regions.Pdf, Jinming Huang, Yunzhou Yang, Gang Liu, Jibin Zhang, Xinxing Dong, Ying Bai, Meiying Fang

Jibin Zhang

Invasive Predators Deplete Genetic Diversity Of Island Lizards, Amandine Gasc, M. C. Duryea, Robert M. Cox, Andrew Kern, Ryan Calsbeek

Dartmouth Scholarship

Invasive species can dramatically impact natural populations, especially those living on islands. Though numerous examples illustrate the ecological impact of invasive predators, no study has examined the genetic consequences for native populations subject to invasion. Here we capitalize on a natural experiment in which a long-term study of the brown anole lizard (Anolis sagrei) was interrupted by rat invasion. An island population that was devastated by rats recovered numerically following rat extermination. However, population genetic analyses at six microsatellite loci suggested a possible loss of genetic diversity due to invasion when compared to an uninvaded island studied over …

Natural Genetic Variation In Selected Populations Of Arabidopsis Thaliana Is Associated With Ionomic Differences, Elizabeth Buescher, Tilman Achberger, Idris Amusan, Anthony Giannini, Cherie Ochsenfeld, Ana Rus, Brett Lahner, Owen Hoekenga, Elena Yakubova, Jeffrey F. Harper, Mary Lou Guerinot, Min Zhang, David E. Salt, Ivan R. Baxter

Dartmouth Scholarship

Controlling elemental composition is critical for plant growth and development as well as the nutrition of humans who utilize plants for food. Uncovering the genetic architecture underlying mineral ion homeostasis in plants is a critical first step towards understanding the biochemical networks that regulate a plant's elemental composition (ionome). Natural accessions of Arabidopsis thaliana provide a rich source of genetic diversity that leads to phenotypic differences. We analyzed the concentrations of 17 different elements in 12 A. thaliana accessions and three recombinant inbred line (RIL) populations grown in several different environments using high-throughput inductively coupled plasma- mass spectroscopy (ICP-MS). Significant …

Plant Genotype And Environment Interact To Influence Soil Carbon And Nitrogen Dynamics, Clara Christina Pregitzer

Masters Theses

Abiotic and biotic variation has been shown to be important in regulating nutrient cycling and belowground communities in natural systems. However, genetic variation in dominant plants as a driver of rates of nutrient cycling is still poorly understood and few studies have looked at genotype interactions across multiple environments. Using Populus angustifolia and a common garden approach, we hypothesized that all three factors: tree genetic variation, environmental conditions and genetic by environment (G x E) interactions would affect soil carbon (C) storage and nitrogen (N) cycling. Replicated copies of five different reciprocally planted Populus genotypes were studied in three separate …

Capturing Genetic Variation During Ecological Restorations: An Example From Kankakee Sands In Indiana, Rebecca W. Dolan, Deborah L. Marr, Andrew Schnabel

Rebecca W. Dolan

Genetic variation in populations, both natural and restored, is usually considered crucial for response to short term environmental stresses and for long term evolutionary change. To have the best chance of successful long-term survival, restored populations should reflect the extant variation found in remnants, but restored sites may suffer from genetic bottlenecks as a result of founder effects. Kankakee Sands is a large-scale restoration being conducted by The Nature Conservancy (TNC) in northwestern Indiana. Our goal was to test for loss of genetic variation in restored plant populations by comparing them with TNC’s seed source nursery and with local remnant …

Capturing Genetic Variation During Ecological Restorations: An Example From Kankakee Sands In Indiana, Rebecca W. Dolan, Deborah L. Marr, Andrew Schnabel

Rebecca W. Dolan

Genetic variation in populations, both natural and restored, is usually considered crucial for response to short term environmental stresses and for long term evolutionary change. To have the best chance of successful long-term survival, restored populations should reflect the extant variation found in remnants, but restored sites may suffer from genetic bottlenecks as a result of founder effects. Kankakee Sands is a large-scale restoration being conducted by The Nature Conservancy (TNC) in northwestern Indiana. Our goal was to test for loss of genetic variation in restored plant populations by comparing them with TNC’s seed source nursery and with local remnant …

Genetic Variation In Past And Current Landscapes: Conservation Implications Based On Six Endemic Florida Scrub Plants, Eric S. Menges, Rebecca W. Dolan, Robert Pickert, Rebecca Yahr, Doria R. Gordon

Rebecca W. Dolan

If genetic variation is often positively correlated with population sizes and the presence of nearby populations and suitable habitats, landscape proxies could inform conservation decisions without genetic analyses. For six Florida scrub endemic plants (Dicerandra frutescens, Eryngium cuneifolium, Hypericum cumulicola, Liatris ohlingerae, Nolina brittoniana, and Warea carteri), we relate two measures of genetic variation, expected heterozygosity and alleles per polymorphic locus (APL), to population size and landscape variables. Presettlement areas were estimated based on soil preferences and GIS soils maps. Four species showed no genetic patterns related to population or landscape factors. The other two species showed significant but inconsistent …

Patterns Of Isozyme Variation In Relation To Population Size, Isolation, And Phytogeographic History In Royal Catchfly, Rebecca W. Dolan

Rebecca W. Dolan

The distribution of genetic variation within and among plant populations is influenced by both contemporary and historical factors. I used isozyme analysis of band phenotypes to examine genetic structure in the rare prairie forb Silene regia. Relationships between current-day population size, isolation, and phenotypic variation were assessed for 18 populations in two regions with differing postglacial history. Western populations from unglaciated southern Missouri and Arkansas were more genetically diverse based on the Shannon-Weaver index (H) and a polymorphic index than were more eastern populations. These differences may be due to loss of variation with repeated founding of new populations in …

Conservation Implications Of Genetic Variation In Three Rare Species Endemic To Florida Rosemary Scrub, Rebecca W. Dolan, Rebecca Yahr, Eric S. Menges, Matthew Halfhill

Rebecca W. Dolan

Habitat conversion and fire suppression during the last 50 yr have greatly reduced and altered Florida scrub vegetation, resulting in threats to the persistence of its unique flora. As part of a larger conservation project, we investigated patterns of isozyme variation in three rare perennial scrub plants with overlapping ranges endemic to Florida rosemary scrub on the Lake Wales Ridge. All three species have low levels of genetic variation, comparable to or lower than those generally reported for rare plants with restricted geographic ranges. Liatris ohlingerae has more than twice the expected heterozygosity of the other two species, with little …

Conservation Implications Of Genetic Variation In Three Rare Species Endemic To Florida Rosemary Scrub, Rebecca W. Dolan, Rebecca Yahr, Eric S. Menges, Matthew Halfhill

Rebecca W. Dolan

Habitat conversion and fire suppression during the last 50 yr have greatly reduced and altered Florida scrub vegetation, resulting in threats to the persistence of its unique flora. As part of a larger conservation project, we investigated patterns of isozyme variation in three rare perennial scrub plants with overlapping ranges endemic to Florida rosemary scrub on the Lake Wales Ridge. All three species have low levels of genetic variation, comparable to or lower than those generally reported for rare plants with restricted geographic ranges. Liatris ohlingerae has more than twice the expected heterozygosity of the other two species, with little …

Genetic Variation At Nuclear Loci Fails To Distinguish Two Morphologically Distinct Species Of Aquilegia, Elizabeth A. Cooper, Justen B. Whittall, Scott A. Hodges, Magnus Nordborg

Biology

Aquilegia formosa and pubescens are two closely related species belonging to the columbine genus. Despite their morphological and ecological differences, previous studies have revealed a large degree of intercompatibility, as well as little sequence divergence between these two taxa [1,2]. We compared the inter- and intraspecific patterns of variation for 9 nuclear loci, and found that the two species were practically indistinguishable at the level of DNA sequence polymorphism, indicating either very recent speciation or continued gene flow. As a comparison, we also analyzed variation at two loci across 30 other Aquilegia taxa; this revealed slightly more differentiation among taxa, …

Genetic Variation In Past And Current Landscapes: Conservation Implications Based On Six Endemic Florida Scrub Plants, Eric S. Menges, Rebecca W. Dolan, Robert Pickert, Rebecca Yahr, Doria R. Gordon

Scholarship and Professional Work - LAS

If genetic variation is often positively correlated with population sizes and the presence of nearby populations and suitable habitats, landscape proxies could inform conservation decisions without genetic analyses. For six Florida scrub endemic plants (Dicerandra frutescens, Eryngium cuneifolium, Hypericum cumulicola, Liatris ohlingerae, Nolina brittoniana, and Warea carteri), we relate two measures of genetic variation, expected heterozygosity and alleles per polymorphic locus (APL), to population size and landscape variables. Presettlement areas were estimated based on soil preferences and GIS soils maps. Four species showed no genetic patterns related to population or landscape factors. The …

Treefrog (Hyla Squirella) Responses To Rangeland And Management In Semi-Tropical Florida, Usa, Kathryn Windes

Electronic Theses and Dissertations

As urban areas expand, agricultural lands become increasingly important habitat for many species. Compared to some types of agricultural land-use, ranchlands provide vast expanses of minimally modified habitat that support many threatened and endangered species. Conservation biologists can promote ecologically sound management approaches by quantifying the effects of agricultural practices on resident species. I examined the effects of pasture management, cattle grazing, and landscape characteristics on both adult and larval treefrogs in a ranchland in south-central Florida. I experimentally determined optimal deployment of artificial treefrog shelters constructed of polyvinylchloride (PVC) pipe to efficiently sample adult treefrogs (Chapter 1). Seventy-two shelters …

Determining The Levels Of Genetic Variation Using Ssr Markers In Three Turkish Barley Materials Known As Tokak, Nejdet Kandemi̇r, Ahmet Yildirim, Rahi̇me Gündüz

Turkish Journal of Agriculture and Forestry

Genetic variations are the raw materials of plant breeding and have been increasingly narrowed due to various reasons. Landraces are good sources of genetic variation, but need to be characterized first. This study was conducted to determine the levels of genetic variation in 3 barley materials originated in Turkey, all known as Tokak. Of the 3 materials used, PI 470281 is a landrace and CIHO 10093 is a pure line. The third is Tokak 157/37, a major cultivar of Turkey considered to be a landrace. In order to detect the levels of polymorphism within and among these materials 30 SSR …