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Genotypic And Phenotypic Adaptations Of The Southern Oyster Drills, Stramonita Canaliculata And S. Haemastoma Floridana To Salinity., Li-Lian Liu Jan 1990

Genotypic And Phenotypic Adaptations Of The Southern Oyster Drills, Stramonita Canaliculata And S. Haemastoma Floridana To Salinity., Li-Lian Liu

LSU Historical Dissertations and Theses

Environmental and genetic effects on salinity adaptation in the southern oyster drill were estimated by their salinity-related genotypic (i.e. determined by electrophoresis) and phenotypic (i.e. determined by salinity tolerance and microcalorimetry) variations. The systematics of Stramonita haemastoma were studied using allozyme, radular and shell characteristics to exclude taxonomic differences which might have obscured variations in salinity adaptation. Radular and shell features are not reliable as systematic characteristics. S. h. canaliculata and S. h. floridana are separable using allozyme characteristics. Nei's genetic distance (D = 0.28) and the fixed allelic differences in Fum, LeuAla, Mdh, and 6-Pgdh indicate that the differences …

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A Comparative Study Of The Effects Of Sesbania Drummondii On The Hepatic Cytochrome P-450 Monooxygenase Systems Of Chickens And Rats., Marcy Iva Banton Jan 1990

A Comparative Study Of The Effects Of Sesbania Drummondii On The Hepatic Cytochrome P-450 Monooxygenase Systems Of Chickens And Rats., Marcy Iva Banton

LSU Historical Dissertations and Theses

The effect of an extract of Sesbania drummondii on the hepatic cytochrome P-450 monooxygenase system was evaluated in two experimental models, the White Leghorn chicken and the Sprague-Dawley rat. The cytochrome P-450 monooxygenase systems were compared using studies of catalytic activities and two major enzyme components, cytochrome P-450 and NADPH-cytochrome P-450 reductase. Two "classical" cytochrome P-450 inducers, phenobarbital and $\beta$-naphthoflavone, were used to probe induction mechanisms. S. drummondii induced opposite effects on the hepatic cytochrome P-450 component of chickens versus rats. Cytochrome P-450 specific content was increased 2-fold in chickens but decreased 2-fold in rats. Qualitative differences in microsomal proteins …

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Isolation And Physical Mapping Of The Mitochondrial Chromosome From The Zygomycete Mucor Racemosus., Mary Louise Schramke Jan 1990

Isolation And Physical Mapping Of The Mitochondrial Chromosome From The Zygomycete Mucor Racemosus., Mary Louise Schramke

LSU Historical Dissertations and Theses

Mitochondria were isolated from Mucor racemosus and DNA was purified from these organelles by cesium chloride/ethidium bromide isopycnic centrifugation. Examination of mitochondrial DNA samples with a transmission electron microscope revealed a circular mitochondrial chromosome approximately 63.8 kbp in length. Summation of restriction fragments of mitochondrial DNA separated by agarose gel electrophoresis yielded a comparable value of 63.4 kbp for the size of the intact molecule. Electrophoretic mobility and stoichiometry were determined for restriction fragments generated using nine different restriction enzymes. A physical map was deduced from single and double digestions of mitochondrial DNA with several of the restriction enzymes. The …

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Plant Allelochemicals And Insect Pathogens: The Effects Of Alpha-Tomatine On The Susceptibility Of Pseudoplusia Includens (Walker) And Heliothis Zea (Boddie) To The Entomogenous Fungus Nomuraea Rileyi (Farlow) Samson., Fernando Covas Gallardo Jan 1990

Plant Allelochemicals And Insect Pathogens: The Effects Of Alpha-Tomatine On The Susceptibility Of Pseudoplusia Includens (Walker) And Heliothis Zea (Boddie) To The Entomogenous Fungus Nomuraea Rileyi (Farlow) Samson., Fernando Covas Gallardo

LSU Historical Dissertations and Theses

Research was conducted to determine the impact of the allelochemical, $\alpha$-tomatine, on the susceptibility of the lepidopterous pests, Heliothis zea (Boddie) and Pseudoplusia includens (Walker) to the entomogenous fungus, Nomuraea rileyi (Farlow) Samson. In one experiment, $\alpha$-tomatine inhibited colony formation and growth of N. rileyi, in vitro. In vivo, larval growth and developmental time of H. zea were affected by $\alpha$-tomatine and N. rileyi. The fungus was detected in the hemolymph and tissue of larvae treated with two concentrations (LC$\sb{50}$ and LC$\sb{90}$) of N. rileyi conidia, including those fed $\alpha$-tomatine. At the LC$\sb{50}$, $\alpha$-tomatine protected larvae against N. rileyi and …

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The Incidence Of Vibrio Species In Louisiana And Maryland Oysters (Crassostrea Virginica)., Mary Lynelle Ford Jan 1990

The Incidence Of Vibrio Species In Louisiana And Maryland Oysters (Crassostrea Virginica)., Mary Lynelle Ford

LSU Historical Dissertations and Theses

Vibrio species, normal inhabitants of the sea and of shellfish harvested from marine or brackish waters, have been established as the causative agents of serious human infections. An investigation to isolate and identity Vibrio species in oysters collected from eight Louisiana commercial oyster beds was conducted. A selection of 127 vibrio isolates and 46 reference strains, including all known Vibrio species, were subjected to a bacteriological identification scheme of 46 parameters. When the data from the wild strains and the reference strains were analyzed by the numerical taxonomy program, TAXAN Version 3.0, six major phena were evident. Four of the …

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Biochemical Characterization And Gene Mapping Of The Channel Catfish Herpesvirus (Ccv)-Encoded Thymidine Kinase, A Selectable Site For Homologous Recombination., Larry Allen Hanson Jan 1990

Biochemical Characterization And Gene Mapping Of The Channel Catfish Herpesvirus (Ccv)-Encoded Thymidine Kinase, A Selectable Site For Homologous Recombination., Larry Allen Hanson

LSU Historical Dissertations and Theses

The channel catfish herpesvirus (CCV) encodes a thymidine kinase (Tk) which is biochemically distinguishable from it's host, the channel catfish ovary (CCO), and other herpesvirus Tk's. Tk deficient CCO cells (CCOBr) were developed by propagating CCO cells in increasing concentrations of 5-bromo-2$\sp\prime$-deoxyuridine (BUdR). CCV infection produced high Tk activity in these Tk deficient cells. This activity was compared to CCO-Tk in ATP and CTP phosphate donor assays, nucleoside substrate-competition and dTTP feedback inhibition assays. The viral Tk was more competitively inhibited by deoxypurines than cellular Tk and showed less dTTP mediated feedback inhibition. CCO-Tk utilized lower concentrations of ATP more …

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The Use Of Cell Culture Systems To Improve Bovine Embryo Viability In Vitro., Stephen Harry Pool Jan 1990

The Use Of Cell Culture Systems To Improve Bovine Embryo Viability In Vitro., Stephen Harry Pool

LSU Historical Dissertations and Theses

Growth characteristics for fetal bovine uterine fibroblast cells (FBUFC) and frozen-thawed bovine (b) and caprine (g) trophoblastic vesicles (TV) were similar in (A) Ham's F-10 (HF-10), (B) MEM (with Earle's salts), (C) RPMI-1640 and (D) Menezo's B$\sb2$ (B$\sb2$), each supplemented with 10% FCS and Ab-Am (Experiment (Exp) I). Cell numbers declined initially but increased linearly thereafter for 5 days. The bTV and gTV that survived freezing had similar viability across time and Treatments (Trt). Exp II compared the (A) bTV, (B) FBUFC monolayer and (C) bTV-monolayer co-culture systems to (D) HF-10 alone for culture of 8- to 32-cell bovine embryos. …

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Louisiana Barrier Island Change Analysis Derived From A Geographic Information System (Gis) Based On Sequential Aerial Photography., Lionel Dorsey Worthy Jr Jan 1990

Louisiana Barrier Island Change Analysis Derived From A Geographic Information System (Gis) Based On Sequential Aerial Photography., Lionel Dorsey Worthy Jr

LSU Historical Dissertations and Theses

Surface feature maps were derived from color-infrared aerial photographs for Louisiana's Timbalier Island and Eastern Isles Dernieres. These provided a basis for the implementation of a barrier island Geographic Information System (GIS), a quantitative spatial framework through which specific proximal and temporal interactions could be examined. This system was utilized to observe relationships between changes in island shorelines and surface areas relative to location and extent of island cover categories. It was further employed to test the applicability of the rollover and deltaic barrier cycle models of island dynamics within the context of the Louisiana coastal environment. Both islands exhibited …

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Identification Of Vibrio Anguillarum And Vibrio Ordalii By A Monoclonal Antibody Coagglutination Assay., Zhongshi Wang Jan 1990

Identification Of Vibrio Anguillarum And Vibrio Ordalii By A Monoclonal Antibody Coagglutination Assay., Zhongshi Wang

LSU Historical Dissertations and Theses

Vibrio anguillarum exhibits species-specific antigens on the protein core of the polar flagellum (H) and H-determinants which are expressed by heterologous Vibrio species. Monoclonal antibody (MAb) which reacted with flagella core protein by ELISA were affinity purified from protein A-sepharose. Staphylococcus aureus Cowan 1 cells armed with anti-H MAb coagglutinated each of the 10 V. anguillarum O-antigen serovars within 1 to 2 minutes, as well as V. ordalii isolates. These findings suggest these two vibrios express similar if not identical species-specific H-determinants. The anti-H reagent did not coagglutinate 20 heterologous Vibrio species. MAb generated against LPS, extracted from V. anguillarum …

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Molecular Cloning And Characterization Of The Rhodobacter Capsulatushema Gene., Maureen Smith Wright Jan 1990

Molecular Cloning And Characterization Of The Rhodobacter Capsulatushema Gene., Maureen Smith Wright

LSU Historical Dissertations and Theses

The first step in the common tetrapyrrole pathway in Rhodobacter capsulatus is the condensation of glycine with succinyl CoA to form 5-aminolevulinate which is then used in the synthesis of bacteriochlorophyll, heme, vitamin B-12, and siroheme. To isolate mutants unable to form 5-aminolevulinate, as a first step in studying regulation of the tetrapyrrole pathway, R. capsulatus was mated with E. coli carrying plasmid pSUP2021. pSUP2021 carries transposon Tn5 and is incapable of replicating in R. capsulatus making it an ideal vector for transposon mutagenesis. One colony was found which requires 5-aminolevulinate for growth. This mutant strain, designated AJB529, has a …

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Brugia Pahangi: Effects Of Maternal Filariasis On The Responses Of Their Progeny To Homologous Infection., Stephen Carl Bosshardt Jan 1990

Brugia Pahangi: Effects Of Maternal Filariasis On The Responses Of Their Progeny To Homologous Infection., Stephen Carl Bosshardt

LSU Historical Dissertations and Theses

The effects of in utero and neonatal exposure to maternal Brugia pahangi infections on the development of homologous infections, immune responses, and pathologic lesions was studied in age-matched progeny of infected and uninfected female jirds. High IgG antibody titers to B. pahangi antigens were present in the sera of progeny from infected mothers. These neonatal titers to homologous antigens were shown to be of maternal origin, and did not alter the cellular responses of uninfected progeny as measured by in vitro antigen-stimulated blastogenesis and in vivo pulmonary granulomatous inflammatory responses to antigen-coated beads. Studies were conducted to measure age-related differences …

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Genetic Comparisons And Systematic Studies Of Termites (Isoptera)., Amy Kathryn Korman Jan 1990

Genetic Comparisons And Systematic Studies Of Termites (Isoptera)., Amy Kathryn Korman

LSU Historical Dissertations and Theses

Eusociality has evolved in only two insect orders: the Isoptera and Hymenoptera. While hymenopteran genetics has been the subject of intensive study, genetic information on termites is conspicuously lacking. The purpose of this dissertation was to utilize starch gel electrophoresis in genetic studies of termites. Chapter I consists of electrophoretic methods and a study of genetic variability among four families of termites. Although some representative species/colonies demonstrated low levels of variation, the ranges of polymorphic loci and gene diversity were within levels generally observed for the class Insecta. Levels of genetic variation exhibited by termites were higher than those values …

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The Socioeconomic Aspects Of Beef Cattle Production In Louisiana., Emmanuel Kagaba Nzabanita Jan 1990

The Socioeconomic Aspects Of Beef Cattle Production In Louisiana., Emmanuel Kagaba Nzabanita

LSU Historical Dissertations and Theses

This study was divided into: (1) a descriptive study of the farm resources, management practices, veterinary services utilization, and socio-psychological characteristics of Louisiana ranchers in relation to beef cattle performance, (b) a classification of the ranchers according to their utilization of veterinary services with the objective of identifying producer characteristics that are associated with frequent, moderate, and non-use of veterinary services, and (c) identification of factors associated with continuing or ending beef cattle production. The intensity of management, herd health and veterinary services utilization was quantified by scoring and ranking indicator variables that defined these composite variables. Most ranchers had …

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Seasonal And Daily Variations In Plasma Hormone Concentrations Of The Gulf Killifish, Fundulus Grandis., Arnil Cabading Emata Jan 1990

Seasonal And Daily Variations In Plasma Hormone Concentrations Of The Gulf Killifish, Fundulus Grandis., Arnil Cabading Emata

LSU Historical Dissertations and Theses

Circadian rhythms of hormone secretion and responsiveness to hormones were examined in the gulf killifish. The findings provide additional information to support the hypothesis that reproductive, metabolic and behavioral activities are regulated in part by a temporal interaction of circadian rhythms. These findings include: (1) Daily injections of drugs that influence serotonergic (5-hydroxytryptophan, 5-HTP) and dopaminergic (dihydroxyphenylalanine, DOPA) activities induce conditions appropriate to either summer or winter, and can determine the manner in which a fish reacts reproductively and metabolically to water temperature, the main environmental determinant. (2) Tryptophan-enriched diets stimulated increases in plasma triiodothyronine and somatomedin-C levels, dramatically stimulated …

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Ribosomal Rna And The Early Evolution Of Flowering Plants., Robert Keith Hamby Jan 1990

Ribosomal Rna And The Early Evolution Of Flowering Plants., Robert Keith Hamby

LSU Historical Dissertations and Theses

Since the end of the last century, the predominant theories of the early radiation of the angiosperms have been that the earliest flowering plants were most similar to the present-day Magnoliidae (sensu Takhtajan, 1969). This position has been adopted by many, though there are some who suggest that the base of angiosperm radiation lies within the monocots (Burger, 1981) or a combination of monocots and dicots (Burger, 1977; Donoghue and Doyle, 1989a, 1989b). Many different ancestors to the angiosperms themselves have been proposed including, at one time or another, most of the extant gymnosperms, extinct gymnosperms and the extinct seed …

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Dead-Leaf Foraging Specialization In Tropical Forest Birds., Kenneth Victor Rosenberg Jan 1990

Dead-Leaf Foraging Specialization In Tropical Forest Birds., Kenneth Victor Rosenberg

LSU Historical Dissertations and Theses

This study investigates an example of extreme foraging specialization by tropical birds, namely foraging for arthropods in suspended aerial leaf-litter in lowland tropical rainforest. Up to 16 species at two southwestern Amazonian sites constitute a guild of specialized dead-leaf foragers that make up roughly 11% of the region's insectivorous bird species. Most dead-leaf specialists are ovenbirds (Furnariidae) or antbirds (Formicariidae) that are characteristic members of mixed-species foraging flocks. Individual dead leaves represent an abundant, seasonally stable resource that supports higher prey densities (number per leaf) and a greater proportion of preferred prey than adjacent live foliage. The arthropod fauna of …

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Biology Of The Twospotted Spider Mite, Tetranychus Urticae (Acari:Tetranychidae) On Several Genotypes Of Soybean And Effects On A Predator Mite, Phytoseiulus Persimilis (Acari:Phytoseiidae)., Jo Ann Canal Wheatley Jan 1990

Biology Of The Twospotted Spider Mite, Tetranychus Urticae (Acari:Tetranychidae) On Several Genotypes Of Soybean And Effects On A Predator Mite, Phytoseiulus Persimilis (Acari:Phytoseiidae)., Jo Ann Canal Wheatley

LSU Historical Dissertations and Theses

In a laboratory experiment with five genotypes of soybean, Glycine max (L.) Merrill, developmental time and fecundity of Tetranychus urticae Koch was measured. Developmental time for virgin females on leaf disks was shortest on Plant Introduction (PI) 227687, 'DSR 352,' and 'Williams.' There were no differences in development time for male mites due to genotype. Females laid more eggs per day on PI 227687 and more total eggs on PI 227687 and 'DSR 352' than on 'Williams,' 'Clark,' and 'Davis.' Life tables were constructed for mite cohorts on each soybean genotype. Values for r, intrinsic rate of increase, ranged from …

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The Introduction Of A Gene Encoding A Novel Peptide Into Plants To Increase Plant Bacterial Resistance., Pablito Garcia Nagpala Jan 1990

The Introduction Of A Gene Encoding A Novel Peptide Into Plants To Increase Plant Bacterial Resistance., Pablito Garcia Nagpala

LSU Historical Dissertations and Theses

A 38 amino acid long peptide, Shiva-1, was designed and chemically synthesized in our laboratory. Shiva-1 has only 46% amino acid homology with the naturally occurring lytic peptide from Hyalophora cecropia, known as Cecropin B. However, hydrophobic properties and charge density of the natural molecule were conserved at 100% in the synthetic peptide. This novel peptide was shown to be capable of killing a number of different species of plant pathogenic bacteria at nanomolar concentrations. Comparative studies show that Shiva-1 is more effective in this bacteriolytic activity than Cecropin B. The gene for Shiva-1 was chemically synthesized and cloned into …

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Ecology Of Small Insectivorous Birds In A Bottomland Hardwood Forest., Wylie Clark Barrow Jr Jan 1990

Ecology Of Small Insectivorous Birds In A Bottomland Hardwood Forest., Wylie Clark Barrow Jr

LSU Historical Dissertations and Theses

Changes in species composition and abundance, habitat use patterns and foraging behavior of 19 bird species in a bottomland hardwood forest in Louisiana were studied during the 1984-1989 breeding seasons. Species that used only one macrohabitat included the Yellow-throated Warbler along oxbow lake margins and the American Redstart, Swainson's Warbler, and Hooded Warbler in non-flooded oak-gum-elm forest. The Northern Parula and Kentucky Warbler used 2 macrohabitats--non-flooded forest and oxbow lake margins. Thirteen species used 3 macrohabitats (non-flooded forest, seasonally flooded forest, and oxbow lake margins). I distinguished 6 groups of species that used similar microhabitat and foraging behavior. Ecological partitioning …

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Semilunar Spawning In Killifish, Fundulus Grandis., Shyh-Min Hsiao Jan 1990

Semilunar Spawning In Killifish, Fundulus Grandis., Shyh-Min Hsiao

LSU Historical Dissertations and Theses

Gulf killifish, Fundulus grandis, spawned daily in aquaria exposed to 12-hr daylengths and 21 to 28$\sp\circ$C temperatures. The number of eggs spawned varied daily producing a peak about every 13.7 days. Ovarian studies indicate that increased maturation of peripheral germinal-vesicle oocytes in preparation for spawning begins five days before the semilunar spawning peak. There is an increase in numbers of hydrated oocytes and ovulated eggs reaching a maximum on or a day before peak spawning. Semilunar spawning cycles of F. grandis are expressions of an endogenous rhythm. Although a specific phase of the semilunar cycle is maintained with respect to …

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The Design And Expression Of A Synthetic Gene Encoding A Novel Polypeptide To Enhance The Quality Of Plant Protein., Jaeho Kim Jan 1990

The Design And Expression Of A Synthetic Gene Encoding A Novel Polypeptide To Enhance The Quality Of Plant Protein., Jaeho Kim

LSU Historical Dissertations and Theses

A novel protein (HEAAE II, High Essential Amino Acid Encoding Protein), rich in essential amino acids (75% of total), was designed and constructed in our laboratory. The monomeric form of the protein consists of 20 amino acid residues with four additional amino acids comprising a potential $\beta$-turn. Circular dichroism and size exclusion analysis demonstrated, that the monomer exists in a stable $\alpha$-helical conformation that self-aggregates in aqueous solution to form higher ordered multimeric structures, which are very reminiscent of natural plant storage proteins. The DNA encoding this amino acid sequence was synthesized, and from this monomeric gene fragment, the tetrameric …

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Assessing The Potential Impact Of Sugarcane Varieties And Predation On Diatraea Saccharalis (F.) Populations In Southern Louisiana., Ricardo Tomas Bessin Jan 1990

Assessing The Potential Impact Of Sugarcane Varieties And Predation On Diatraea Saccharalis (F.) Populations In Southern Louisiana., Ricardo Tomas Bessin

LSU Historical Dissertations and Theses

To facilitate a better understanding of how varietal resistance and predation affect area-wide sugarcane borer populations, several studies were undertaken before the development of a simulation model. The first study was a 3-year investigation into the compatibility and contributions of varietal resistance, arthropod predation and insecticide toward sugarcane borer control. Insecticides were shown to be the predominant management factor preventing plant injury, but varietal resistance appeared nearly as important in terms of sugarcane borer population regulation in sugarcane. The next study assessed a moth production index in addition to the percentage of bored internodes as a tool for quantifying varietal …

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Evaluation Of Aeromonas Hydrophila Virulence Factors: Role In Natural Epizootics And Their Use As Potential Immunogens., Larisa Ann Ford Jan 1990

Evaluation Of Aeromonas Hydrophila Virulence Factors: Role In Natural Epizootics And Their Use As Potential Immunogens., Larisa Ann Ford

LSU Historical Dissertations and Theses

Aeromonas hydrophila and A. sobria have been identified as major causes of mortalities among commercially raised channel catfish and are the cause of septicemic diseases in a wide variety of other animals. At present, antibiotic therapy is the only prescribed treatment for Motile Aeromonad Septicemia (HAS) in channel catfish. Antibiotic treatment, however, is expensive and often not effective due to the development of resistance in the bacterial strains. Development of immunoprophylatic methods for the prevention of HAS would be of value and use to the commercial catfish industry. Several studies have demonstrated that whole cell vaccine preparations do not confer …

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Management Of Tobacco Budworm, Heliothis Virescens (F.) And Bollworm, Helicoverpa Zea (Boddie) In Cotton: Host Plant Resistance And Ovicidal Approaches., Billy Rogers Leonard Jan 1990

Management Of Tobacco Budworm, Heliothis Virescens (F.) And Bollworm, Helicoverpa Zea (Boddie) In Cotton: Host Plant Resistance And Ovicidal Approaches., Billy Rogers Leonard

LSU Historical Dissertations and Theses

Growth, development and survival of pyrethroid-resistant (PY-R) and -susceptible (PY-S and FIELD-88) tobacco budworm, Heliothis virescens (F.), and bollworm (CORN-BW), Helicoverpa zea (Boddie), were compared on four cotton lines ('Deltapine 41', La. HG-660, La. HG-063 and PD-0804) and artificial diet. The FIELD-88 and CORN-BW strains had significantly higher 5 and 9 day larval weights compared to the PY-R and PY-S laboratory strains. Larvae fed squares of La. HG-660 and La. HG-063 had significantly lower larval and pupal weights, required significantly more days to pupate and had higher cumulative mortality compared to those reared on squares of a commercial cultivar, Deltapine …

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Environmental And Economic Influences On The Oyster Fishery Of Lower Barataria Bay, Louisiana., Earl Joseph Melancon Jr Jan 1990

Environmental And Economic Influences On The Oyster Fishery Of Lower Barataria Bay, Louisiana., Earl Joseph Melancon Jr

LSU Historical Dissertations and Theses

A three year study, 1982-85, of eight oystermen bedding on 19 leases in lower Barataria Bay was designed to determine lease production, fuel, labor and energy inputs and the expenses to operate. The data was then incorporated into a bioeconomic model of the lower Bay. Commercial yield ratios (sacks harvested:sacks bedded) per lease ranged from 0.03$-$1.68:1. The two lowest lease yields were the result of vandalism and poaching, respectively. A multiple linear equation developed from the data predicts that as salinity and water temperature increase, lease yields decrease. Utilization of the Bay's bedding leases are dependent on seed obtained from …

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Reproductive Biology Of Pinus Sylvestris L.: Seed Yield, Flower Phenology, The Response Of Young Seedlings To Ga 4/7, And Developmental Anatomy, Teresa K. Boes Dec 1989

Reproductive Biology Of Pinus Sylvestris L.: Seed Yield, Flower Phenology, The Response Of Young Seedlings To Ga 4/7, And Developmental Anatomy, Teresa K. Boes

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.

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Linkage Analysis Of Reading Disability On Chromosome 6., Yin Yao Shugart Aug 1989

Linkage Analysis Of Reading Disability On Chromosome 6., Yin Yao Shugart

Student Work

Reading disability (RD) is defined as difficulty learning to read and spell despite adequate intelligence and educational opportunity and without demonstratable physical, neurological, or emotional handicap. Investigators have suggested a genetic influence and postulated an autosomal dominant mode of inheritance. The strongest support for this hypothesis came from the observation of linkage between RD and a heteromorphism of the short arm/centromere of chromosome 15. Further analysis indicated the possibility of genetic heterogeneity with some families showing RD due to a gene not on chromosome 15. This research is a report of the results of a linkage analysis of RD verses …

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Amino Acid Uptake And Metabolism By Larvae Of The Marine Worm Urechis Caupo (Echiura), A New Species In Axenic Culture, William Jaeckle, Donal T. Manahan Jun 1989

Amino Acid Uptake And Metabolism By Larvae Of The Marine Worm Urechis Caupo (Echiura), A New Species In Axenic Culture, William Jaeckle, Donal T. Manahan

Scholarship

Axenic (bacteria-free) larval cultures of the marine echiuran worm, Urechis caupo, were reliably obtained by aseptically removing gametes directly from the gamete storage organs. Trochophore larvae only removed neutral amino acids from seawater as measured by high-performance liquid chromatography (HPLC). There was no detectable uptake, as measured by HPLC, of acidic or basic amino acids. Kinetic analysis showed that the transport system for alanine in 4-day-old larvae had a Kt of 4-6 μM and a Jmax of 9-10 pmol larva-1 h-1. Following a 50-min exposure, the majority of the radio-activity (95%) from 14 …

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Response Of Big Bluestem (Andropogon Gerardii Vitman) To Specific Date Of Spring Burning., Tracy Lea Benning May 1989

Response Of Big Bluestem (Andropogon Gerardii Vitman) To Specific Date Of Spring Burning., Tracy Lea Benning

Student Work

The tallgrass prairie of central North America has been described as a fire-derived and fire-maintained ecosystem (Stuart 1951) in which fires occurred intermittently and throughout the year (Jackson 1965). Because of the importance of fire to this ecosystem, its effects have been widely studied and summarized in reviews by Ehrenreich (1959), Daubenmire (1968), Vogl (1974), and Hulbert (1986). The effect of burning during different seasons has been studied with varying results. Winter burns reduce herbage production of warm-season dominants and shift vegetational composition by differentially favoring cool-season species (e.g. Towne and Owensby 1984). Mid-to late-season fires also damaged the C4 …

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The Foraging Behavior, Habitat Use, And Diet Of Arctic Foxes (Alopex Lagopus) In A Goose Nesting Area Near Kokechik Bay, Alaska, Alice Allgood Stickney Apr 1989

The Foraging Behavior, Habitat Use, And Diet Of Arctic Foxes (Alopex Lagopus) In A Goose Nesting Area Near Kokechik Bay, Alaska, Alice Allgood Stickney

Biological Sciences

The foraging behavior, habitat use, and diet of arctic foxes were observed in a goose nesting area near Kokechik Bay, Alaska during the summers of 1985 and 1986. The foraging patterns of arctic foxes changed after birds started nesting in the study area, adding an abundant egg resource to a previously limited prey base. The duration of search bouts decreased and success rate increased, yielding an increased prey capture rate. Over 80% of the eggs taken by foxes during the nesting stage were cached, rather than eaten immediately. Differences in search patterns among foxes were probably related to the different …

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