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Dispersion And Physiological Ecology Of Mosquito Adults In Louisiana Ricelands., Alan Richard Holck Jan 1989

Dispersion And Physiological Ecology Of Mosquito Adults In Louisiana Ricelands., Alan Richard Holck

LSU Historical Dissertations and Theses

A sampling technique for estimating the size of adult mosquito populations in vegetation was developed. Regression analysis was used to obtain absolute density estimates from sweep net. Diurnal population size estimates of Louisiana riceland mosquitoes were made on a 35.6-square km site 5 km south of Kaplan, LA. Four mosquito species were present: Psorophora columbiae, Anopheles quadrimaculatus, An. crucians and Culex salinarius. Mosquito species were highly stratified in their distribution. Psorophora columbiae was primarily observed in pastures with livestock and in rice fields. Both Anophelines were found only in structures. Culex salinarius did not exhibit habitat preference. Anopheles quadrimaculatus exhibited …

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Molecular Biological Studies On The Degradation Of Diphenyl Ethers By Bacteria., Hung-Ming James Liaw Jan 1989

Molecular Biological Studies On The Degradation Of Diphenyl Ethers By Bacteria., Hung-Ming James Liaw

LSU Historical Dissertations and Theses

Microbial degradation of diphenyl ethers was studied utilizing several different approaches. The first approach was to isolate mutants from a ligninolytic Erwinia sp. by conventional mutagenesis and selection. A copper-resistant mutant, designated as Erwinia sp. CU3614, was isolated and characterized to be capable of degrading diphenyl ethers as well as one dibenzo-p-dioxin in the presence of copper ions. Isolation of Tn5 transposon-induced mutants of Erwinia sp. CU3614, which lost degradation ability, demonstrated that in all probability a copper-associated activity in the biotransformation of aromatic ethers was involved. In order to study the degradation at the molecular biological level, a 2.1 …

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Ecological Consequences Of Variation In Pollinator Availability: Ocotillo, Carpenter Bees, And Hummingbirds In Two Deserts., Peter Evans Scott Jan 1989

Ecological Consequences Of Variation In Pollinator Availability: Ocotillo, Carpenter Bees, And Hummingbirds In Two Deserts., Peter Evans Scott

LSU Historical Dissertations and Theses

I studied the pollination ecology of a widespread desert shrub, ocotillo (Fouquieria splendens), and some of the consequences of geographic variation in availability of pollinators. I studied ocotillo in the Chihuahuan Desert of western Texas (Big Bend National Park) for three flowering seasons, and in the Sonoran Desert of southern California (Anza-Borrego Desert State Park) for parts of two flowering seasons. In both areas, ocotillo flowers profusely for one month each year, and requires outcross pollination to mature more than 5% of its potential seed crop. In Texas, carpenter bees (Xylocopa californica arizonensis) and their nest plants (species of Agave, …

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Avian Influenza Viruses In Coastal Louisiana Waterfowl: Host And Environmental Factors Affecting Prevalence And Viral Persistence., David Edward Stallknecht Jan 1989

Avian Influenza Viruses In Coastal Louisiana Waterfowl: Host And Environmental Factors Affecting Prevalence And Viral Persistence., David Edward Stallknecht

LSU Historical Dissertations and Theses

Cloacal and tracheal swabs were collected from 1,389 hunter-killed ducks in Cameron Parish, Louisiana during the 1986 and 1987 waterfowl seasons. These included 605 blue-winged teal (Anas discors), 75 mottled ducks (A. fulvigula), 375 gadwalls (A. strepera) and 334 green-winged teal (A. crecca). Twenty-eight avian influenza viruses (AIVs) were isolated. Prevalence estimates of AIV in ducks during September, November and December/January were 3.1%, 2.1%, and 0.4%, respectively. Differences in prevalence were detected by season ($P$ =.044) and age class ($P$ =.036). Two isolations from resident mottled ducks indicate local transmission of AIV on these wintering areas. Much subtype diversity was …

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The Impact Of Vertebrate Herbivores On Primary Production Of Sagittaria Marshes In The Wax Lake Delta, Atchafalaya Bay, Louisiana., Jenneke Maria Visser Jan 1989

The Impact Of Vertebrate Herbivores On Primary Production Of Sagittaria Marshes In The Wax Lake Delta, Atchafalaya Bay, Louisiana., Jenneke Maria Visser

LSU Historical Dissertations and Theses

Aboveground production of tidal freshwater marshes dominated by Sagittaria latifolia or Sagittaria platyphylla is best estimated with nondestructive techniques. A nondestructive method for estimation of Sagittaria aboveground biomass and production was developed using multiple regression. This technique yielded estimates of aboveground biomass of Sagittaria ranging from 0 to 1875 g/m$\sp2$; harvested aboveground biomass of Sagittaria ranged from 85 to 1356 g/m$\sp2$. Aboveground production was estimated nondestructively on the basis of permanent plots (465-3809 g/m$\sp2$/yr) and destructively on the basis of end-of-season biomass (775-4056 g/m$\sp2$/yr). Destructively estimated belowground production ranged from 233 to 1199 g/m$\sp2$/yr. Aboveground production was positively correlated with …

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Phosphatidylethanolamine Synthesis By A Base Exchange Reaction In Castor Bean Endosperm., Sungho Shin Jan 1989

Phosphatidylethanolamine Synthesis By A Base Exchange Reaction In Castor Bean Endosperm., Sungho Shin

LSU Historical Dissertations and Theses

An ethanolamine base exchange enzyme has been assayed in the endoplasmic reticulum (ER) of castor bean (Ricinus communis L. var. Hale) endosperm. The activity was maximal at ethanolamine concentrations of 30 uM in the presence of 2 mM CaCl$\sb2$. The optimum pH was 7.8 using HEPES buffer. Under these conditions, the enzyme had a maximum enzyme velocity of approximately 0.3 nmol h$\sp{-1}$ mg$\sp{-1}$ protein and an apparent Km of 5.0 uM for ethanolamine. A maximum velocity of approximately 1.7 nmol h$\sp{-1}$ mg$\sp{-1}$ protein was obtained under similar conditions with L-serine at about 400 uM in a serine base exchange reaction. …

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The Evolution Of Igg And Igm Antibodies To Antigens Of Mycobacterium Leprae In Experimentally Inoculated Armadillos., Abdul Reza Vadiee Jan 1989

The Evolution Of Igg And Igm Antibodies To Antigens Of Mycobacterium Leprae In Experimentally Inoculated Armadillos., Abdul Reza Vadiee

LSU Historical Dissertations and Theses

The nine-banded armadillo (Dasypus novencinctus linn.) is highly susceptible to infection with M. leprae and has become an important animal model in the study of leprosy. In an attempt to define the major immunogens of M. leprae and the isotypic antibody response to these molecules during infection, the IgG and IgM antibody responses of experimentally-infected armadillos to the sonicated M. leprae, supernatant fraction of sonicated M. leprae, lipoarabinomannan derived from M. tuberculosis, and phenolic glycoliopid-I was analyzed using immunoblot and ELISA. Antibodies to the specific epitope (defined by monoclonal antibody IIIE9) on the 65-kDa protein of M. leprae were analyzed …

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Ecological And Genetic Aspects Of The Population Biology Of The Littoral Rotifer Euchlanis Dilatata, Elizabeth Jensen Walsh Jan 1989

Ecological And Genetic Aspects Of The Population Biology Of The Littoral Rotifer Euchlanis Dilatata, Elizabeth Jensen Walsh

UNLV Retrospective Theses & Dissertations

Littoral rotifers are associated with vegetation and thus live in highly structured habitats. This structural complexity increases the possibilities of forming local subpopulations differing in (a) plant substrate used, (b) biotic interactions, and (c) genetic structure. I explore some of these topics in populations of the littoral rotifer Euchlanis dilatata; I investigated several aspects of egg-laying behavior in 3 clones of E. dilatata. Individuals lay their eggs randomly within culture dishes in the absence of substrate, while eggs laid in the presence of an artificial substrate are deposited in clumps by 2 of the 3 clones. When given a choice …

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Studies On Trypanosoma Cruzi Isolates From Louisiana Mammals With Particular Reference To Infectivity To Dogs., Stephen Charles Barr Jan 1989

Studies On Trypanosoma Cruzi Isolates From Louisiana Mammals With Particular Reference To Infectivity To Dogs., Stephen Charles Barr

LSU Historical Dissertations and Theses

This dissertation describes studies on three Trypanosoma cruzi isolates from Louisiana mammals with particular reference to infectivity to dogs. Isolates from an opossum (Tc-O) and armadillo (Tc-A) were obtained during a blood culture survey of these animal populations in Louisiana. Prevalence of T. cruzi were 37.5% and 1% in opossums and armadillos respectively. Further, 48% opossums had myocarditis suggestive of T. cruzi infection. Rural dogs with known contact with T. cruzi hosts, housed rural dogs, urban animal shelter dogs and household pets showed 4.7, 0, 2.3 and 0% serological prevalence to T. cruzi respectively. Tc-O and Tc-A (wild isolates) displayed …

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Isolation, Characterization, And Symbiotic Effectiveness In Soybeans Of Exopolysaccharide Mutants Of Rhizobium Fredii Usda191., Young Hwan Ko Jan 1989

Isolation, Characterization, And Symbiotic Effectiveness In Soybeans Of Exopolysaccharide Mutants Of Rhizobium Fredii Usda191., Young Hwan Ko

LSU Historical Dissertations and Theses

Chapter 1. Production of exopolysaccharides by Rhizobium has been linked with efficient invasion and nodulation of leguminous plant roots by the bacteria. Exopolysaccharide-deficient (exo) mutants of Rhizobium fredii USDA191 were isolated by Tn5-insertion mutagenesis. Five phenotypically unique exo mutants were investigated for exopolysaccharide synthesis and their ability to nodulate soybeans. The exopolysaccharides produced by these mutants were analyzed for polysaccharide composition by column chromatography and thin layer chromatography. Two mutants designated exo3 and exo5 were deficient in both the neutral glucan and exopolysaccharide synthesis, but still made effective nodules on Glycine max cv. Peking, although with decreased efficiency. The remaining …

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Marsh:Water Column Interactions In Two Louisiana Estuaries. Flux Measurements And Conceptual Implications., Daniel Louis Childers Jan 1989

Marsh:Water Column Interactions In Two Louisiana Estuaries. Flux Measurements And Conceptual Implications., Daniel Louis Childers

LSU Historical Dissertations and Theses

Many important ecosystem-level processes are integrated in hydrologically-forced marsh:water column interactions in estuaries. In this work, I quantified nutrient and sediment fluxes in two Louisiana estuaries using throughflow marsh flumes. The Barataria Basin estuary is in an later, deteriorating stage of the deltaic cycle. Brackish and saline marshes here exported dissolved inorganic nitrogen (DIN), total nitrogen, and dissolved organics (DOM); phosphorus fluxes were low and variable. Fourleague Bay marshes, in a earlier developmental stage of the deltaic cycle, imported DIN in the spring and released DIN in summer and fall. In this way, marshes here buffer open-bay N concentrations from …

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Floral Ontogeny Of Mimosoid Legumes., Jose Israel Ramirez-Domenech Jan 1989

Floral Ontogeny Of Mimosoid Legumes., Jose Israel Ramirez-Domenech

LSU Historical Dissertations and Theses

Comparative floral ontogeny in mimosoid legumes was analyzed among representative genera in three major tribes Mimoseae, Acacieae and Ingeae. Details on floral and inflorescence ontogeny in one mimosoid species is described and illustrated for Mimosa strigillosa Torr. & Gray. Three features studied developmentally include: variation in number of parts, patterns of arrangement and inflorescence architecture. Suppression occurs along inflorescences that develop synchronously, when basal flowers are retarded. Tetramerous flowers are considered a reduction or suppression from basic pentamerous flower. Divergent patterns in order of sepal initiation and stamen initiation and proliferation are found during early ontogeny. Four patterns found in …

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Habitat Differentiation Of Iris Fulva Ker Gawler, Iris Hexagona Walter, And Their Hybrids., Bobby Dale Bennett Jan 1989

Habitat Differentiation Of Iris Fulva Ker Gawler, Iris Hexagona Walter, And Their Hybrids., Bobby Dale Bennett

LSU Historical Dissertations and Theses

Iris fulva and Iris hexagona have overlapping geographic ranges in Louisiana; in areas of overlap hybrids are fairly common. Iris hexagona occupies the borders of freshwater marshes of southern Louisiana while I. fulva can be found farther north along edges of natural levees, canals and swamps. An area of hybridization (hybrid zone) can be found where bayous penetrate the freshwater marsh. The objective of this research was to investigate some of the factors affecting habitat differentiation of I. fulva, I. hexagona, and their natural hybrids ("Hybrid Purple" and "Hybrid Red"). A three year field study was conducted to determine the …

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Isolation And Characterization Of A Rhodobacter Capsulatus Biob Mutant Using A Novel Method To Screen For Strains Unable To Synthesize Heme., Rhonda Diane Cardin Jan 1989

Isolation And Characterization Of A Rhodobacter Capsulatus Biob Mutant Using A Novel Method To Screen For Strains Unable To Synthesize Heme., Rhonda Diane Cardin

LSU Historical Dissertations and Theses

The common tetrapyrrole pathway of the photosynthetic bacterium, Rhodobacter capsulatus, ultimately leads to the synthesis of bacteriochlorophyll, heme, vitamin B-12, and siroheme. Molecular analysis of tetrapyrrole biosynthesis has been limited due to a lack of mutants. This study describes the isolation and characterization of a biotin-requiring mutant of R. capsulatus unable to synthesize heme. Growth conditions were established to allow selection and characterization of heme-deficient strains of R. capsulatus. A screening method was developed to isolate strains of R. capsulatus unable to synthesize heme. Tn5 derivatives of a bchB strain that exhibited an altered ability to synthesize the fluorescent porphyrin …

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Characterization Of The Transcriptional Properties Of Equine Infectious Anemia Virus., Siyamak Rasty Jan 1989

Characterization Of The Transcriptional Properties Of Equine Infectious Anemia Virus., Siyamak Rasty

LSU Historical Dissertations and Theses

The transcriptional properties of equine infectious anemia virus were examined in two distinct equine cell lines in which the virus establishes either a persistent or a cytopathic infection. Northern hybridization analyses were performed to determine the number, sizes, and relative levels of the EIAV transcripts encoded during persistent or cytopathic infections. Three species of viral mRNA were detected in infected cells: an 8.2-kb full-length genomic mRNA, a 3.5-kb single-spliced mRNA, and a low abundance 1.5-kb mRNA, presumably formed by a double-splicing event of the full-length mRNA. Analysis of the levels of EIAV-specific RNA's present during persistent and cytopathic infections has …

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Genetics And Morphology Associated With The Flowering Pattern, Flowers, And Leaves Of Capsicum Annuum L. And Capsicum Chinense Jacq., Dai-Mei Shuh Jan 1989

Genetics And Morphology Associated With The Flowering Pattern, Flowers, And Leaves Of Capsicum Annuum L. And Capsicum Chinense Jacq., Dai-Mei Shuh

LSU Historical Dissertations and Theses

The leaves and the flowers of Capsicum annuum L. and Capsicum chinense Jacq. were morphologically and genetically studied. C. annuum sets one flower at each node; C. chinense sets multiple (two or three) flowers at each node. 'Serrano Chili' (C. annuum L.) has an unique pubescent leaf type. The study on the interspecific hybridization between 'Serrano Chili' and No. 178 (C. chinense Jacq.) showed a F2 segregation ratio 45:9:10 (multiple flowers: intermediate flowering type: single flower) for the inheritance of multiple flowers. The interspecific hybridization, together with the intraspecific hybridization of 'Serrano Chili' crossed with 'Keystone Resistant Giant No. 4', …

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Age And Growth Of Red Drum, Sciaenops Ocellatus, And Black Drum, Pogonias Cromis, In The Northern Gulf Of Mexico., Daniel William Beckman Jan 1989

Age And Growth Of Red Drum, Sciaenops Ocellatus, And Black Drum, Pogonias Cromis, In The Northern Gulf Of Mexico., Daniel William Beckman

LSU Historical Dissertations and Theses

The objectives of this study were to obtain age estimates and describe growth for the two sciaenid fish species, red drum Sciaenops ocellatus and black drum Pogonias cromis, in the northern Gulf of Mexico. Age estimates were made using annulus counts in transverse sections of otoliths (inner ear bones). Aging techniques were validated for juvenile red drum by imparting oxytetracycline into otoliths as a time marker. Recaptures validated that annuli were deposited in otoliths yearly up to 2.5 years age, with the first annulus formed in the second winter at 1-1.5 years age. Age estimates for remaining age classes of …

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Ecological Studies Of Velvetbean Caterpillar, Anticarsia Gemmatalis Hubner, Pupae In Louisiana Soybean Fields., Joon-Ho Lee Jan 1989

Ecological Studies Of Velvetbean Caterpillar, Anticarsia Gemmatalis Hubner, Pupae In Louisiana Soybean Fields., Joon-Ho Lee

LSU Historical Dissertations and Theses

The microhabitat distribution of velvetbean caterpillar (VBC), Anticarsia gemmatalis Hubner (Lepidoptera: Noctuidae) was studied in soybean field cages and fields during 1985, 1986 and 1987. Larval density did not affect pupal horizontal distribution patterns related to direction and distance from the plant row. Pupae were found equally on both sides of soybean plant rows in a cage study. Pupae were found on and below the soil surface, but not on the plant. In 51 cm row spacing, both equal number and similar dispersion pattern of pupae were found on either side of the plant row. In 91 cm row spacing, …

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Molecular Genetic And Biochemical Analyses Of A Dna Repair Gene From Serratia Marcescens., Keith Eugene Murphy Jan 1989

Molecular Genetic And Biochemical Analyses Of A Dna Repair Gene From Serratia Marcescens., Keith Eugene Murphy

LSU Historical Dissertations and Theses

In Escherichia coli, the SOS response and two 3-methyladenine DNA glycosylases (TagI and TagII) are required for repair of DNA damaged by alkylating agents such as methyl methanesulfonate (MMS). Mutations of the recA gene eliminate the SOS response. TagI and TagII are encoded by the tag and alkA genes, respectively. A gene (rpr) encoding 3-methyladenine DNA glycosylase activity was isolated from the Gram-negative bacterium Serratia marcescens. The gene, localized to a 1.5-kilobase pair SmaI-HindIII restriction fragment, was cloned into plasmid pUC18. The clone complemented E. coli tag alkA and recA mutations for MMS resistance. The rpr gene did not, however, …

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Feeding And Foraging Behaviors Of Subterranean Termites (Isoptera:Rhinotermitidae)., Keith Scott Delaplane Jan 1989

Feeding And Foraging Behaviors Of Subterranean Termites (Isoptera:Rhinotermitidae)., Keith Scott Delaplane

LSU Historical Dissertations and Theses

Six studies were done on feeding and foraging behaviors of three species of subterranean termites, Coptotermes formosanus Shiraki, Reticulitermes flavipes (Kollar), and R. virginicus (Banks) (Isoptera: Rhinotermitidae). When presented with four equal wood blocks, C. formosanus did not forage randomly but concentrated on a few preferred blocks. When R. flavipes and C. formosanus were each placed in foraging arenas with linear, successive wood blocks, C. formosanus consumed a greater percentage dry mass of a wood block before moving to the next block (10.3%) than did R. flavipes (4.2%). Groups of C. formosanus were offered wood blocks that differed in initial …

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Molecular Characterization Of Fall Armyworm Mitochondrial-Dna (Spodoptera Frugiperda (J. E. Smith);)., Li Dao Ke Jan 1989

Molecular Characterization Of Fall Armyworm Mitochondrial-Dna (Spodoptera Frugiperda (J. E. Smith);)., Li Dao Ke

LSU Historical Dissertations and Theses

Chapter I. Mitochondrial DNA (mtDNA) was isolated, purified from pooled samples of fall armyworm (FAW), Spodoptera frugiperda, and characterized. The yield of mtDNA from adults ranged from 45 to 114 ng per moth. Entire mtDNA from adult FAW showed 1 to 3 electrophoretic bands when electrophoresed on agarose gels. When digested with SalI or XhoI restriction endonucleases, all DNA forms co-migrated as single bands with the same mobility. XbaI cleaved the mtDNA into three fragments of 8083 $\pm$ 524, 6179 $\pm$ 430, and 1990 $\pm$ 140 base pairs (bp). The FAW mitochondrial genome size was calculated to be 16,253 $\pm$ …

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Effects Of Genetic Traits On Nonlint Trash And Nep Content Of Cotton, Gossypium Hirsutum L., Ricardo Gabriel Novick Jan 1989

Effects Of Genetic Traits On Nonlint Trash And Nep Content Of Cotton, Gossypium Hirsutum L., Ricardo Gabriel Novick

LSU Historical Dissertations and Theses

Gin induced lint quality problems (neps, short fiber content, seed-coat fragments and reductions in lint turnout) need the consideration of the entire cotton production system. Genetic traits could help reduce seed-cotton trash and/or improve cleanability at the gin. Twelve near-isolines involving four leaf shapes (okra, semi-okra, super-okra and normal), two bract types (frego and normal), two leaf-pubescence levels (semi-smoothness and hairy) and certain trait combinations were grown during 1985, 1986, and 1987 at three locations in Louisiana (Alexandria, Bossier City, and St. Joseph), and harvested with a spindle-picker. Seedcotton samples were ginned on a cut-down version of a commercial gin …

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Vegetation Of The Coniferous-Deciduous Forest Overlap Region Along The Niobrara River Valley Of North-Central Nebraska., Carol Sue Crosby Jul 1988

Vegetation Of The Coniferous-Deciduous Forest Overlap Region Along The Niobrara River Valley Of North-Central Nebraska., Carol Sue Crosby

Student Work

Introduction: The Niobrara River Valley of north central Nebraska is recognized as an area in which elements of the Rocky Mountain (coniferous), Boreal, and Eastern Deciduous forests meet. These elements occur primarily along river bluffs in an area surrounded by grasslands (Bessey 1887, Pound and Clements 1900, Tolstead 1947, Nixon 1967, Kaul 1975). In this region many species of plants and animals reach their distributional limits (Tolstead 1942). Diverse topography, north/south slope microclimates, soil, hydrology and geologic history have contributed to creating this biological crossroads amidst a chiefly grassland climate.

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Presettlement Savanna In Eastern Nebraska., Mary K. Rozmajzl May 1988

Presettlement Savanna In Eastern Nebraska., Mary K. Rozmajzl

Student Work

Introduction: Oak (Quercus)-dominated savannas once occurred throughout central North America (Nuzzo 1986) although few remain today. The decline of this ecosystem is largely due to the impact of European settlers who either cleared the savanna or altered the environment to the extent that savannas have succeeded to forests (Cottam 1949, Grimm 1981).

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Annual Report, Botanical Garden Report, Spring 1988, Frederick B. Essig Apr 1988

Annual Report, Botanical Garden Report, Spring 1988, Frederick B. Essig

USF University Archives and Documents

Annual report of accomplishments for the University of South Florida Botanical Gardens, submitted by Frederick B. Essig for Spring 1988. Includes educational mission of the gardens, overview of specimens, staffing plans, and programming description.

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Nutrient Reserves Of Lesser Snow Geese During Winter And Spring Migration, Ray Tomas Alisauskas Jan 1988

Nutrient Reserves Of Lesser Snow Geese During Winter And Spring Migration, Ray Tomas Alisauskas

Digitized Theses

I studied body composition, diet, and behavior of midcontinent lesser snow geese (Chen caerulescens caerulescens) on their major winter areas and during spring migration from January to May 1983-84. Members of this population regularly overwinter in three habitats--marshes along the Gulf of Mexico, rice fields in Texas and Louisiana contiguous to coastal marshes, and corn fields in Iowa, Missouri, and Kansas. Lesser snow geese did not store nutrient reserves that could be considered to have been for the purpose of reproduction the following spring. Differences in accessibility of foods in different winter habitats and the feeding mode required to obtain …

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Ultrastructure And Atpase Nature Of Polar Membrane In Campylobacter Jejuni, Frances Marguerite Brock Jan 1988

Ultrastructure And Atpase Nature Of Polar Membrane In Campylobacter Jejuni, Frances Marguerite Brock

Digitized Theses

The ultrastructure of polar membrane in Campylobacter jejuni was examined and was shown to line the cytoplasmic membrane at the poles of the cell like an internal cylindrical cap. The component parts of polar membrane (stalks and knobs) were found to be consistent with previous reports of this structure, although their dimensions were smaller than those described for Ectothiorhodospira mobilis.;Polar membrane in C. jejuni was visualized on membrane vesicles. It was composed of dough-nut shaped particles 5-6 nm in diameter, arranged in an hexagonal array.;C. jejuni sheds its flagella and varying proportions of the poles of the cell, resulting in …

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Aspects Of The Dispersal Ecology Of Solanum Dulcamara L (Solanaceae) Near London, Ontario, Daniel Hugh Broderick Jan 1988

Aspects Of The Dispersal Ecology Of Solanum Dulcamara L (Solanaceae) Near London, Ontario, Daniel Hugh Broderick

Digitized Theses

Field and laboratory studies of aspects of the dispersal ecology of Solanum dulcamara, a perennial species bearing fleshy fruits, were conducted near London, Ontario. Although there were annual and inter-habitat variations, 51.9% of the dispersant fruits were not ripe. Each fruit type contained some viable seeds, but germination and seedling emergence were more rapid from ripe fruits. Seeds from which the flesh had been removed produced seedlings at a faster rate than seeds sown within intact fruits. Seeds sown within intact fruits were more likely to produce seedlings in later years. In one such study the bulk of seedlings emerged …

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Ultrastructural And Associated Biochemical Changes Related To The Endogenous Rhythm And Flowering Response In Chenopodium Rubrum, Isabel Joy Dickson-Clark Jan 1988

Ultrastructural And Associated Biochemical Changes Related To The Endogenous Rhythm And Flowering Response In Chenopodium Rubrum, Isabel Joy Dickson-Clark

Digitized Theses

Experimental work is carried out using seedlings of the early flowering Chenopodium rubrum system. Flowering can be controlled photoperiodically. Growth and development in terms of plastochron stage, ontogenetic state, at the apex within the differing experimental treatments are examined as are the effects of the light and dark treatments. The plastochron age differs among seedlings of the same chronological age under differing treatments. Effect of the dark is to produce a delay in normal growth and development; this is concommitant with flower induction; the ontogenetic stage of induced apices in the light following the dark is dependent only on the …

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Molecular Biological Studies On The Rep Gene Of Escherichia Coli, Carol Anne Gilchrist Jan 1988

Molecular Biological Studies On The Rep Gene Of Escherichia Coli, Carol Anne Gilchrist

Digitized Theses

My work has involved the sequencing of the Escherichia coli rep gene. This gene codes for the Rep helicase, a ssDNA-dependent ATPase required by some phages ({dollar}\Phi{dollar}X174, fd, P2) for their replication.;The section of E. coli chromosome known to contain the rep gene, which I have sequenced, has only one transcribed open reading frame of the correct size to encode the Rep protein. The predicted N-terminal amino acids and the predicted total amino acid composition are in agreement with those determined from purified Rep protein.;The proposed amino acid sequence of Rep contains in its N terminus a peptide common to …

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