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Botany

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Full-Text Articles in Life Sciences

Investigating The Ecology Of A Rare Species On St. John, Usvi: Reintroducing Solanum Conocarpum In Light Of Climate Change, Cecilia Rogers Jan 2018

Investigating The Ecology Of A Rare Species On St. John, Usvi: Reintroducing Solanum Conocarpum In Light Of Climate Change, Cecilia Rogers

Senior Honors Projects, 2010-current

Approximately two thirds of St. John is National Park territory. However, the land has been threatened with tourism and development, greatly impacting island biodiversity. One species that may become extinct due to this degradation is Solanum conocarpum. S. conocarpum is a rare shrub, endemic to the dry tropical forests of St. John, USVI. This plant is a species of conservation concern and is one of very few native and endemic plants on this island. Very little is known about the ecology and reproduction of S. conocarpum. Most plants are found on the southern half of the island. Recent observations have ...


An Assessment Of How Plant And Mycorrhizal Communities Have Been Affected Along A Mine-Impacted Watershed In The Northwest Territories, Kevin Maccoll Jan 2017

An Assessment Of How Plant And Mycorrhizal Communities Have Been Affected Along A Mine-Impacted Watershed In The Northwest Territories, Kevin Maccoll

Theses and Dissertations (Comprehensive)

Giant Mine is an inactive gold mine located nine kilometers north of Yellowknife, Northwest Territories. Giant Mine has been the source of arsenic trioxide for the Baker Creek watershed since it opened over 60 years ago. Although arsenic levels in the creek are above the limits considered to be biologically relevant, there is no concrete evidence that plants and mycorrhizae have actually been affected. This study provides an initial assessment of the impacts mining activity at Giant Mine has had on plants and mycorrhizae in the Baker Creek watershed. Nine sites were sampled around Giant Mine: five sites downstream from ...


Using Morphometrics To Evaluate Taxonomic Relationships In Eleocharis Tenuis (Cyperaceae), Lane D. Gibbons May 2016

Using Morphometrics To Evaluate Taxonomic Relationships In Eleocharis Tenuis (Cyperaceae), Lane D. Gibbons

Masters Theses

North America is host to multiple complex taxa, and unresolved relationships in the genus Eleocharis (Cyperaceae). Of noteworthy significance, are lasting taxonomic uncertainties involving plants referable to E. tenuis (var. tenuis, var. verrucosa, and var. pseudoptera) of the E. tenuis species complex. Morphology of E. tenuis is traditionally recognized as being widely variable, and intermediate among taxa along a broad geographic gradient. Cytological and morphometric data however, indicate that the varieties of E. tenuis are unique in cytology, and are consistently delimited by five morphological characters. Furthermore, this study shows that cytological data correlates with unique morphological entities, and that ...


The Evolution And Influence Of Art In Scientific Illustration, Ahsiya Rebecca Zurita Jan 2016

The Evolution And Influence Of Art In Scientific Illustration, Ahsiya Rebecca Zurita

Senior Projects Spring 2016

Senior Project submitted to The Division of Arts of Bard College.


Mechanisms Of Native Shrub Encroachment On A Virginia Barrier Island, Joseph Thompson Jan 2016

Mechanisms Of Native Shrub Encroachment On A Virginia Barrier Island, Joseph Thompson

Theses and Dissertations

Species composition, temperature, soil nutrients, and leaf area index (LAI) were recorded across three encroaching Morella cerifera thicket edges and three free- standing shrubs on Hog Island, Virginia to characterize the effect of shrub thickets on the plant community and microclimate. Electron transport rate (ETR) was taken on shrub leaves to determine if microclimate benefits M. cerifera physiology. Species richness was lowest inside shrub thickets. Soil water content and LAI were higher in shrub thickets compared to grassland. Soil organic matter, N, and C were higher inside shrub thickets. Summer and fall maximum temperatures were more moderate in shrub thickets ...


Plant Community Development Of Isle Royale's Moose-Spruce Savannas, Michael C. Rotter May 2014

Plant Community Development Of Isle Royale's Moose-Spruce Savannas, Michael C. Rotter

All NMU Master's Theses

On Isle Royale National Park, heavy moose browsing over the past 100 years has suppressed the regeneration of many tree species, gradually resulting in a shift towards more open forests and savannas. By 1996, 16% of the forests at the southwest end of Isle Royale had become savanna and another 20% were starting to break-up. The changes in understory vegetation brought about by savanna formation have received little attention, even though the future of moose and wolf populations on Isle Royale are tied to these vegetation changes. This study examined the vegetation of savannas ranging in age (date since formation ...


The Vascular Flora Of Powhatan County, Virginia, Michael Austin Terry Jan 2005

The Vascular Flora Of Powhatan County, Virginia, Michael Austin Terry

Master's Theses

The project was undertaken with three main goals in mind: to provide as current and complete an account as possible of the flora of Powhatan County in the form of an annotated checklist; to integrate the information obtained from the inventory into phytogeographical and ecological generalizations currently being developed for the state of Virginia; and, to report any significant or anomalous discoveries. There is no previous county-wide inventory of plant diversity for Powhatan County. However, Corcoran (1981) published a list of plants from the Jones and Mill Creek watershed located in the Fine Creek Mills area of northeastern Powhatan.


Phylogeny And Morphological Evolution Of The Chenopodiaceae-Amaranthaceae Alliance , Donald B. Pratt Jan 2003

Phylogeny And Morphological Evolution Of The Chenopodiaceae-Amaranthaceae Alliance , Donald B. Pratt

Retrospective Theses and Dissertations

Phylogenetic analysis of plastid encoded ndhF coding sequences for the Chenopodiaceae-Amaranthaceae alliance reveals a monophyletic Chenopodiaceae-Amaranthaceae clade sister to Achatocarpaceae. The Chenopodiaceae-Amaranthaceae-Achatocarpaceae clade is in turn sister to the Caryophyllaceae, the Chenopodiaceae-Amaranthaceae-Achatocarpaceae-Caryophyllaceae clade forming a separate lineage within order Caryophyllales. The Chenopodiaceae as currently circumscribed is paraphyletic and the alliance breaks into a polytomy of four major clades: (i) Amaranthaceae-Polycnemoideae, (ii) Chenopodieae-Atripliceae, (iii) SalicornioideaeSalsoloideae, and (iv) Beteae. Character-state optimizations of morphological characters mapped onto ndhF sequence derived phylogenies reveal phylogenetically significant patterns of character-state distribution. Morphological investigations also revealed a previously undetected branching pattern in the Gomphrenoideae, which is here ...


Phylogenetic Studies Of Tribe Cacteae (Cactaceae) With Special Emphasis On The Genus Mammillaria , Charles A. Butterworth Jan 2003

Phylogenetic Studies Of Tribe Cacteae (Cactaceae) With Special Emphasis On The Genus Mammillaria , Charles A. Butterworth

Retrospective Theses and Dissertations

The genus Mammillaria is probably the most species-rich genus in the cactus family. To date, there have been a number of infrageneric classifications of the genus, based largely on morphological data. This study utilized molecular (DNA) sequence data from two chloroplast markers (rpl16 intron and the psbA- trnH intergenic spacer) as part of a cladistic study of the genus. However, in order to allow the choice of a suitable outgroup for Mammillaria an initial study used sequence data from the rpl16 intron to investigate phylogenetic relationships in Tribe Cacteae (to which Mammillaria belongs). The result of that study revealed numerous ...


Molecular Genetic Studies Of Acetyl-Coa Carboxylase And 3-Methylcrotonyl-Coa Carboxylase In Plants , Hui-Rong Qian Jan 2002

Molecular Genetic Studies Of Acetyl-Coa Carboxylase And 3-Methylcrotonyl-Coa Carboxylase In Plants , Hui-Rong Qian

Retrospective Theses and Dissertations

Similar reverse-genetics approach is applied to investigate the function of two biotin-containing enzymes at the interface between catabolism and anabolism: acetyl-CoA carboxylase (ACCase) and 3-methylcrotonyl-CoA carboxylase (MCCase).;Plastidic ACCase catalyzes the first committed step of de novo fatty acid biosynthesis. Antisense Arabidopsis expressing antisense RNA of CAC1-A, which encodes the biotin carboxyl carrier protein (BCCP) of plastidic ACCase under the direction of CaMV 35S promoter, have been obtained. CAC1-A antisense plants with reduced BCCP possess different degrees of similar morphological changes. These include slow growth, smaller plant size, and crinkly and variegated-yellow vegetative and cauline leaves eventually leading to premature ...


Atp-Citrate Lyase Has An Essential Role In Cytosolic Acetyl-Coa Production In Arabidopsis , Beth Leann Fatland Jan 2002

Atp-Citrate Lyase Has An Essential Role In Cytosolic Acetyl-Coa Production In Arabidopsis , Beth Leann Fatland

Retrospective Theses and Dissertations

Acetyl-CoA is both an essential primary and secondary metabolite, however, the source of cytosolic acetyl-CoA has been unclear. We identified two non-overlapping groups of plant cDNAs that encode proteins similar to the amino and carboxy portions of human ATP-citrate lyase. In Arabidopsis, three genes encode the 45 kD ACLA subunit (ACLA-1, At1g10670; ACLA-2, At1g60810; ACLA-3, At1g09430) and two genes encode the 65 kD ACLB subunit (ACLB-1, At3g06650; ACLB-2, At5g49460). Co-expression of ACLA-1 and ACLB-2 cDNAs in Saccharomyces cerevisiae yields ATP-citrate lyase activity, indicating both polypeptides are required for activity. The Arabidopsis holoprotein has a molecular weight of 500 kDa, which ...


Insertional Mutagenesis Of The Signal Transduction Pathway For Low Co2 Acclimation In Chlamydomonas Reinhardtii , Kyujung Van Jan 2001

Insertional Mutagenesis Of The Signal Transduction Pathway For Low Co2 Acclimation In Chlamydomonas Reinhardtii , Kyujung Van

Retrospective Theses and Dissertations

Chlamydomonas reinhardtii shows adaptive changes in order to survive in limiting CO2 conditions because they live in quite variable conditions of CO2 availability. We are trying to identify mutants defective in the acclimation response to limiting CO 2. Nuclear transformation to complement an Arg- phenotype was used to generate insertional mutants, and Cah1 expression and having high CO2-requiring (HCR) phenotype were used as reporters for induction of genes involved in acclimation to limiting CO 2.;Among a collection of insertionally generated mutants, a mutant has been isolated that showed no pCA1 protein and no Cah1 mRNA. This mutant strain, designated ...


The Role Of Small-Scale Disturbances In Structuring The Plant Community Of Native And Reconstructed Prairies , Kelly S. Wolfe-Bellin Jan 2001

The Role Of Small-Scale Disturbances In Structuring The Plant Community Of Native And Reconstructed Prairies , Kelly S. Wolfe-Bellin

Retrospective Theses and Dissertations

Understanding the link between pattern and process is an important goal in ecology, and much research has focused on how small-scale disturbances act to produce spatial patterns in plant communities. In this research, I investigated the role of small-scale disturbances in structuring the plant communities of native and reconstructed prairies, with an explicit emphasis placed on understanding how spatial and temporal patterns in disturbance production affect seedling recruitment.;Two studies investigated the spatial and demographic effects of gopher mound production on four plant species in a native prairie. The spatial distributions of three species were positively related to the pattern ...


Floristic Analysis Of Central Iowa Woodlands, And Comparison Of Reproduction And Regeneration In Common And Restricted Herbaceous Species , Catherine Mary Mabry Jan 2000

Floristic Analysis Of Central Iowa Woodlands, And Comparison Of Reproduction And Regeneration In Common And Restricted Herbaceous Species , Catherine Mary Mabry

Retrospective Theses and Dissertations

I studied the distribution and abundance of the plant species of forests in central Iowa, emphasizing the effect of cattle grazing on the vegetation. I used traits to identify groups of species that may function as guilds, and to address whether species' frequency was related to traits. To understand the difference between species that were common compared to those relatively less common (restricted species), I examined whether the two groups differed in reproductive output and allocation, seed viability, and seedling emergence;Understory species and canopy trees were generally distributed along the same environmental gradients. These were landform, soil phosphorous and ...


Carbohydrate Regulation Of Leaf Development: Investigating The Role Of Source Strength, Carbon Partitioning And Hexokinase Signaling In Regulating Leaf Senescence , Adam Christopher Miller Jan 2000

Carbohydrate Regulation Of Leaf Development: Investigating The Role Of Source Strength, Carbon Partitioning And Hexokinase Signaling In Regulating Leaf Senescence , Adam Christopher Miller

Retrospective Theses and Dissertations

For many plants, growth in elevated CO2 leads to reduced rates of photosynthesis. To examine the role leaf ontogeny plays in acclimation; we monitored photosynthesis and some related parameters throughout the development of tobacco leaves under ambient and high CO2 conditions. The pattern of photosynthetic rate over time was consistent with the expected pattern for a typical dicot leaf for both. However, the photosynthesis pattern in high-CO2-grown tobacco was shifted temporally to an earlier maximum and subsequent senescent decline. Rubisco activity appeared to be the main factor regulating photosynthetic rates in both treatments. Therefore, we propose a new model for ...


The Influence Of Vegetation And Landscape On The Forest Bird Community Of Northeast Iowa , William Russell Norris Jan 1999

The Influence Of Vegetation And Landscape On The Forest Bird Community Of Northeast Iowa , William Russell Norris

Retrospective Theses and Dissertations

I studied bird community dynamics and habitat associations of forest birds in northeast Iowa in 1995 and 1996. During this study, 107 different bird species were detected in northeast Iowa forests, including many neotropical migrant songbirds. However, a nest parasite, the brown-headed cowbird ( Molothrus ater), was the most frequently detected bird during this study. The abundance and species richness of birds (both expressed as mean numbers per bird census point at each site) were both higher in 1995 but the rank orders of bird species in 1995 and 1996 were highly correlated, suggesting stable bird community structure over time;Most ...


The Positional Cloning And Expression Studies Of The Immutans Variegation Locus Of Arabidopsis Thaliana , Dongying Wu Jan 1999

The Positional Cloning And Expression Studies Of The Immutans Variegation Locus Of Arabidopsis Thaliana , Dongying Wu

Retrospective Theses and Dissertations

immutans (im), a nuclear gene induced variegation mutation of Arabidopsis, causes green- and white-sectored leaves and is recessive. The green sectors contain cells with normal chloroplasts, whereas the white sectors are heteroplastidic and contain cells with abnormal, pigment-deficient plastids as well as some normal chloroplasts. The white sectors accumulate the carotenoid precursor phytoene. We have cloned IM by chromosome walking and found that the gene encodes a 40.5-kD chloroplast thylakoid membrane protein with sequence motifs characteristic of alternative oxidase, a mitochondrial protein that functions as a terminal oxidase in the respiratory chains of all plants. IM protein functions as ...


Biochemical Characterization And Positional Cloning Of The Var2 Variegation Mutant Of Arabidopsis Thaliana , Meng Chen Jan 1999

Biochemical Characterization And Positional Cloning Of The Var2 Variegation Mutant Of Arabidopsis Thaliana , Meng Chen

Retrospective Theses and Dissertations

Chloroplasts differentiation and development are highly coordinated with their host cells. To better elucidate the mechanisms involved in nuclear-chloroplast interactions, we characterized a nuclear encoded leaf variegation mutation called var2. While cotyledons appear normal, true leaves of var2 emerge as yellow, then turn into green-white sectors. The green sectors contain cells with normal chloroplasts, whereas the white sectors contain cells with abnormal plastid lacking of internal membrane structures. The phenotypes suggested that VAR2 might be involved in thylakoid biogenesis in early chloroplast differentiation. We cloned the VAR2 gene by a map-based method. Five original and two potential alleles were sequenced ...


Molecular Phylogeny Of The Portulacaceous Cohort , Wendy Linn Applequist Jan 1999

Molecular Phylogeny Of The Portulacaceous Cohort , Wendy Linn Applequist

Retrospective Theses and Dissertations

The central focus of this research is the use of chloroplast ndhF sequence data to produce a phylogeny of the Portulacaceae, including an evaluation of the relationships of this family to the Basellaceae, Cactaceae, and Didiereaceae. This cohort was divided into two major clades, both including genera of the Portulacaceae; the Cactaceae were derived from the first, and the Basellaceae and Didiereaceae from the second. Within the latter, a largely Western American assemblage of genera, some formerly identified as basal taxa, was found to be monophyletic. This phylogeny indicated that all recent infrafamilial classifications of the Portulacaceae were flawed by ...


Evolution Of The Alcohol Dehydrogenase Gene Family In Diploid And Tetraploid Gossypium L , Randall Lee Small Jan 1999

Evolution Of The Alcohol Dehydrogenase Gene Family In Diploid And Tetraploid Gossypium L , Randall Lee Small

Retrospective Theses and Dissertations

Molecular data have had a profound effect on the field of plant evolutionary biology, yet the potential wealth of data stored in low-copy nuclear-encoded genes has been virtually ignored, relative to studies of chloroplast and ribosomal DNA. In this dissertation I present an analysis of a model nuclear-encoded gene family (alcohol dehydrogenase, Adh) in a model organismal system, the cotton genus (Gossypium L., Malvaceae);A combination of PCR- and Southern hybridization-based approaches was employed to isolate, sequence, and map multiple Adh gene family members. Diploid Gossypium contain at least seven Adh loci. Sequence analysis reveals extensive intron variation between loci ...


Molecular Systematics In Gossypium And Its Relatives , Tosak Seelanan Jan 1998

Molecular Systematics In Gossypium And Its Relatives , Tosak Seelanan

Retrospective Theses and Dissertations

Gossypium L. is an economically important genus as it harbors four species that provide the cotton of commerce. Although many aspects of the evolution and taxonomy of Gossypium are well understood, there has been little work devoted to assessing relationships among Gossypium and its allied genera. In addition, newly discovered species, of Gossypium sect. Grandicalyx from Australia, have prompted a need for more research into the phylogeny of these new species and their relationships to other Gossypium taxa. Multiple data sets were used to address questions regarding (1) phylogenetic relationships among Gossypium and its relatives, and (2) the phylogeny and ...


Nodulation And Expression Of The Early Nodulation Gene, Enod2, In Temperate Woody Legumes Of The Papilionoideae , Carol Marie Foster Jan 1998

Nodulation And Expression Of The Early Nodulation Gene, Enod2, In Temperate Woody Legumes Of The Papilionoideae , Carol Marie Foster

Retrospective Theses and Dissertations

Understanding dinitrogen-fixing symbioses in economically important, temperate, woody legumes requires evaluating their nodulation status and studying molecular mechanisms of nodulation and dinitrogen fixation. Styphnolobium japonicum (L.) Schott and Cladrastis kentukea (Dum.-Cours.) Rudd were examined for the capacity to form root nodules. Inoculations with various broad-range rhizobia, soil and rhizobia from closely related species of Sophora, and soil from S. japonicum and C. kentukea in Japan, China, and the United States did not elicited nodulation. As an unexpected consequence of these experiments, rhizobia were isolated for the first time from nodules of Maackia floribunda Takeda, and most tested isolates also ...


Vegetation Dynamics In Prairie Wetlands , Eric William Seabloom Jan 1997

Vegetation Dynamics In Prairie Wetlands , Eric William Seabloom

Retrospective Theses and Dissertations

I designed and implemented three studies exploring the factors controlling the development of vegetative zonation in prairie wetlands. In the first study, I used growth chamber experiments to examine the effects of water depth and temperature on seedling recruitment from a wetland seed bank. Regression analysis indicated that both water depth and temperature affected the composition of the seedling community. Annual species richness declined in richness. Perennial species richness increased in richness with decreasing temperature. Species that were found in deep water as adults germinated at higher rates in the flooded treatments, while species that occurred at higher elevations as ...


Characterization Of The Expression Of Two Maize Root-Preferential Genes At The Protein Level , Lathika Pinto Moragoda Jan 1997

Characterization Of The Expression Of Two Maize Root-Preferential Genes At The Protein Level , Lathika Pinto Moragoda

Retrospective Theses and Dissertations

The zrp2 gene encodes an mRNA that accumulates preferentially in roots of maize. To study zrp2 gene expression at the protein level, an antibody was raised against an E. coli-produced ZRP2 protein. Western analyses using this antibody revealed an approximately 100 kDa protein in seedling roots that was not detected in seedling leaves. This size is about 30 kDa larger than the predicted molecular weight. Within seedling roots, low levels of ZRP2 protein were detected in the root tip and high levels were detected throughout the rest of the root. In mature maize plants, the ZRP2 protein was present at ...


Molecular Evolution At Homoeologous Loci In Allotetraploid Cotton (Malvaceae: Gossypium Hirsutum L) , Richard Clark Cronn Jan 1997

Molecular Evolution At Homoeologous Loci In Allotetraploid Cotton (Malvaceae: Gossypium Hirsutum L) , Richard Clark Cronn

Retrospective Theses and Dissertations

Duplicated genes created during polyploid formation ('homoeologues') may experience a variety of fates depending upon the evolutionary forces operating on these loci. Homoeologue divergence may be limited if selection operates to maintain duplicate gene function, or divergence may be permitted if selective pressure on a functionally redundant locus is relaxed. In an attempt to determine the fate of duplicate loci in a polyploid genome, I have isolated and described sequence evolution at 15 sets of homoeologous loci from allotetraploid cotton (Gossypium L.) and the corresponding orthologues from its progenitor diploid genomes. Homoeology and orthology relationships of these loci have been ...


Analyses Of A Genic Male-Sterile Mutant In Soybean , Wei Jin Jan 1997

Analyses Of A Genic Male-Sterile Mutant In Soybean , Wei Jin

Retrospective Theses and Dissertations

A new genic male-sterile mutant in soybean was characterized genetically, developmentally, and molecularly. This mutant is controlled by a single recessive gene, which is not allelic to six previously identified soybean genic male-sterile mutants: ms1, ms2, ms3, ms4, ms5, or ms6. No linkage was detected between the male-sterile gene and flower color (W1 locus), or between the male-sterile gene and pubescence color (T1 locus). Developmental and enzymatic studies showed that sterility was caused by retention of the callose walls, which normally are degraded by callase ([beta]-1,3-glucanase) at the late tetrad stage. Molecular markers linked with the male-sterile gene ...


Genetic Characterization Of Northern Flints And Flours Maize (Zea Mays L. Spp. Mays) With Isozyme, Ssr, And Morphological Markers, William Gerardo González Ugalde Jan 1997

Genetic Characterization Of Northern Flints And Flours Maize (Zea Mays L. Spp. Mays) With Isozyme, Ssr, And Morphological Markers, William Gerardo González Ugalde

Retrospective Theses and Dissertations

The Northern Flints and Flours (NF), one of the more important races for maize breeders and scientists, is one of the progenitors of Corn Belt Dents (CB). Despite its importance this race is not well-characterized. Therefore, an assessment of the utility of different methods for genetic characterization of the NF was conducted. Genetic variation in 40 representative germplasm accessions of the racial groups NF, CB, and Southern Dents (SD), maize from the southwestern US and northern Mexico, and maize intermediate between the NF and the other groups, were evaluated with morphological, isozyme and SSR markers. SSR loci proved to be ...


A Phylogenetic Study Of Ferocactus Britton And Rose (Cactaceae: Cactoideae) , Jorge Hugo Cota-Sánchez Jan 1997

A Phylogenetic Study Of Ferocactus Britton And Rose (Cactaceae: Cactoideae) , Jorge Hugo Cota-Sánchez

Retrospective Theses and Dissertations

Ferocactus is the third largest genus in the tribe Cacteae of the Cactoideae, and the number of species is still matter of taxonomic discussion. The different interpretation of morphological characters has led to discrepancies in species boundaries. This dissertation includes four papers describing the taxonomic history of Ferocactus to elucidate its evolutionary history and phylogenetic relationships with related taxa of the tribe Cacteae. The first paper is a general review of Ferocactus and summarizes the knowledge of the genus and discusses the relevance of understanding its phylogenetic relationships at the specific, generic and tribal levels. The second paper is a ...


Expression Of Genes Encoding Acetyl-Coa Carboxylase, Biotin Synthase, And Acetyl-Coa Generating Enzymes In Arabidopsis Thaliana , Jinshan Ke Jan 1997

Expression Of Genes Encoding Acetyl-Coa Carboxylase, Biotin Synthase, And Acetyl-Coa Generating Enzymes In Arabidopsis Thaliana , Jinshan Ke

Retrospective Theses and Dissertations

Acetyl-CoA carboxylase catalyzes the formation of malonyl-CoA from acetyl-CoA. The four genes encoding heteromeric acetyl-CoA carboxylase are coordinately expressed in leaves, flowers, and developing siliques and embryos. The highest expression occurs in tissues undergoing rapid growth and high oil deposition. The gene encoding the E1 [beta] subunit of chloroplastidic pyruvate dehydrogenase has an identical pattern, indicating it may provide acetyl-CoA for seeds. In contrast, the gene encoding acetyl-CoA synthetase has a different expression pattern and is expressed at low levels in seeds;The ACC1 genes encoding homomeric acetyl-CoA shows transient expression in a variety of cell types. The homomeric acetyl-CoA ...


Nitrate Removal Capacity Of Constructed Wetlands , Richard Gregory Phipps Jan 1997

Nitrate Removal Capacity Of Constructed Wetlands , Richard Gregory Phipps

Retrospective Theses and Dissertations

Constructed wetlands at the Des Plaines Wetland Demonstration Project in Wadsworth, Illinois were examined for their capacity to remove nonpoint source loads of nitrate from an agricultural watershed. Three flow through wetlands received different loading rates of pumped river water with seasonably variable loads of nitrate and organic nitrogen. The nitrogen removal capacities of the wetlands were estimated using mass balance and sediment-water microcosms for the 1991 and 1992 field seasons. Concentrations of nitrogen and flow volumes were monitored at inlets and outlets and mass balances of nitrogen loads were calculated. The wetlands received two different loading rates in 1991 ...