Life Sciences Commons^™

The Effect Of Temperature And Humidity On The Bionomics Of Six African Egg Parasitoids (Hymenoptera: Trichogrammatidae), A. Kalyebi, W. A. Overholt, F. Schulthess, J. M. Mueke, S. Sithanantham

All Peer-Reviewed Publications

The life table statistics of six native Kenyan species/strains of Trichogramma and Trichogrammatoidea were established using a factitious host Corcyra cephalonica, Stainton (Lepidoptera: Pyralidae), at eight different temperatures (10, 15, 20, 25, 28, 30, 32 and 35°C) and two humidity levels (40-50 and 70-80%). The objective was to select insects with superior attributes for augmentative release against lepidopteran pests in horticultural crops. Both temperature and humidity affected developmental time and life table parameters of the parasitoids but temperature played a more critical role. Developmental time was inversely related to temperature. The intrinsic and finite rates of increase increased with temperature …

Contribution Of Natural Food Sources To Reproductive Behaviour, Fecundity And Longevity Of Ceratitis Cosyra, C. Fasciventris And C. Capitata (Diptera: Tephritidae), A. Manrakhan, S. A. Lux

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The influence of food sources comprising the natural diet on the reproductive behaviour, fecundity and longevity of three African fruit flies Ceratitis cosyra (Walker), C. fasciventris (Bezzi) and C. capitata (Wiedemann) was investigated. Three natural food sources, varying in protein and sugar content, were evaluated. These included bird droppings (farm chicken), aphid honeydew and guava (Psidium guajava L.) juice. For C. fasciventris and C. capitata, flies fed on a protein-rich diet displayed higher frequency of calling, mating and oviposition than flies fed on a protein-poor diet, whilst for C. cosyra, quality of diet significantly influenced the mating behaviour of the …

Spatially Targeting Culex Quinquefasciatus Aquatic Habitats On Modified Land Cover For Implementing An Integrated Vector Management (Ivm) Program In Three Villages Within The Mwea Rice Scheme, Kenya, Benjamin G. Jacob, Josephat Shililu, Ephantus J. Muturi, Joseph M. Mwangangi, Simon M. Muriu, Jose Funes, John Githure, James L. Regens, Robert J. Novak

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Background: Continuous land cover modification is an important part of spatial epidemiology because it can help identify environmental factors and Culex mosquitoes associated with arbovirus transmission and thus guide control intervention. The aim of this study was to determine whether remotely sensed data could be used to identify rice-related Culex quinquefasciatus breeding habitats in three rice-villages within the Mwea Rice Scheme, Kenya. We examined whether a land use land cover (LULC) classification based on two scenes, IKONOS at 4 m and Landsat Thematic Mapper at 30 m could be used to map different land uses and rice planted at different …

Phylogenetic Study Of Diadegma Species (Hymenoptera: Ichneumonidae) Inferred From Analysis Of Mitochondrial And Nuclear Dna Sequences, Barbara Wagener, Annette Reineke, Bernhard Löhr, Claus P.W. Zebitz

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The genus Diadegma consists of a large group of parasitoid wasps with a confusing taxonomy based on morphological characters. No phylogenetic studies on this genus or any of its species have been published so far. We examined DNA variations in a 498 bp segment of the cytochrome oxidase I gene (COI) of mitochondrial DNA (mtDNA) and in the internal transcribed spacer 2 (ITS2) of ribosomal DNA (rDNA) and compared nine different Diadegma species (i.e., D. semiclausum, D. insulare, D. fenestrale, D. mollipla, D. rapi., D. leontiniae, D. chrysostictos, D. armillata, D. blackburni) from various geographical origins. Interspecific variation ranged from …

Mate Location Mechanism And Phase-Related Mate Preferences In Solitarius Desert Locust, Schistocerca Gregaria, Sidi Ould Ely, Hassan Mahamat, Peter G.N. Njagi, Magzoub Omer Bashir, Salah El-Tom El-Amin, Ahmed Hassanali

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Mate location responses of male and female solitary-reared locusts that had either experienced no crowding or that had been crowded for varying periods were studied in a flatbed wind tunnel. Two hypotheses were explored: that both sexes of this phase of the locust participate in locating the other by using a combination of chemical and visual signals, and that individuals that experience some crowding (i.e., undergo varying levels of phase shift) can compete effectively with their solitary counterparts in mate location and mating. Our results confirm that both male and female solitarious locusts actively participate in mate location, although the …

Psd-Project Sequence Database, Matthew Kayala, Akhila Kambhampati, Stephanie Forschner, Bethany D. Jenkins

Bioinformatics Software Design Projects

1. Introduction

The sequencing of nucleic acids and the subsequent analysis of their encoded the genes and proteins has revolutionized biological sciences and allowed for the determination of evolutionary origins and biochemical potential of organisms. While the technology to determine molecular sequence data has become extremely powerful in terms of both automation and thoughput, sequence analysis technology has lagged behind, unable to efficiently keep up with the vast amount of sequence data being generated both in individual labs and by researchers worldwide. The foundation of robust sequence analysis is dependent on the building and maintaining of project sequence databases (PSD) …

A Probabilistic Approach To Model The Nonisothermal Nucleation Of Triacylglycerol Melts, Alejandro G. Marangoni, Thomas C. Aurand, Silvana Martini, Michel Ollivon

Nutrition, Dietetics, and Food Sciences Faculty Publications

Crystallization studies are usually performed under isothermal conditions. Kinetic parameters characterizing the isothermal nucleation and growth processes can be obtained using classical nucleation and growth models. However, crystallization regimes found in nature, as well as those used in food and pharmaceutical processing, are rarely isothermal. Focusing on the nucleation stage, the approach followed in this work was to define a new parameter to characterize the driving force of nucleation, the supercooling-time exposure (β), which not only depends on the difference between the melting temperature (Tm) and the onset temperature of nucleation (Tc) ΔTc but also on the induction time of …

Comparison Of The Ingestion And Digestion Rates Of Ochromonas Danica Grazing On Pseudomonas Fluorescens Of Varying Food Quality, Stephen Paul Shannon

Biology Dissertations - Archive

Flagellate prey selection appears to depend on morphological characteristics of prey such as cell size and motility, as well as on physiochemical characteristics such as digestibility and cell surface characteristics. Pseudomonas fluorescens was grown in chemostats at four dilution rates (0.03, 0.06, 0.10, 0.13 h-1) and three temperatures (14, 20, 28°C) to produce cells of varying morphological characteristics (cell size) and physiochemical characteristics or food quality (as determined by the C:N:P ratio). Heat-killed bacteria of a given food quality were prepared and used to grow the flagellate Ochromonas danica. Ingestion and digestion rates were determined using fluorescently labeled bacteria of …

The Water Vapor Permeability Of Polycrystalline Fat Barrier Films, Silvana Martini, D. A. Kim, M. Ollivon, A. G. Marangoni

Nutrition, Dietetics, and Food Sciences Faculty Publications

The water vapor permeability of fat barrier films has been associated with structural characteristics such as polymorphism, crystal size, and chemical composition, among others. However, no mechanistic models have been proposed to describe this relationship. In this study, we have determined the effects of processing conditions on the structure and physicochemical characteristics of four fats and their relationship to water vapor permeability. Results suggest that the solids' volume fraction and the domain size of the fat crystals seem to be the most important factors controlling water vapor migration. Moreover, materials with relatively large crystalline domains will yield malleable films with …

Diel Periodicity In The Production Of Green Leaf Volatiles By Wild And Cultivated Host Plants Of Stemborer Moths, Chilo Partellus And Busseola Fusca, K. Chamberlain, Z. R. Khan, J. A. Pickett, T. Toshova, L. J. Wadhams

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The volatile chemicals produced by four poaceous plant species, blue thatching grass, Hyparrhenia tamba, Napier grass, Pennisetum purpureum, sorghum, Sorghum bicolor, and maize, Zea mays, which are host plants for the lepidopterous stemborers, Chilo partellus and Busseola fusca, were collected by air entrainment and analyzed by gas chromatography. The total quantities of volatiles collected hourly, over a 9-hr period, from P. purpureum and H. tamba showed an approximately hundredfold increase in the first hour of the scotophase. Thereafter, the amount decreased rapidly to levels present during photophase. Although onset of scotophase also triggered an increase in quantities of volatiles collected …

Queen Weights Of Polygyne Solenopsis Invicta And S. Xyloni Suggest Reduced Competitive Ability, Ricardo A. Ramirez, D C. Thompson

Biology Faculty Publications

Solenopsis invicta Buren populations were confirmed in southern New Mexico, resulting in a quarantine of Doña Ana County in 1998; however, Solenopsis xyloni McCook remains the dominant fire ant. This study compared the queen weights and egg production of polygyne colonies of both species. There was no difference in live weights of the major worker caste; however, queens were very different in weight. In this study, S. invicta queens weighed almost twice as much as S. xyloni (S. invicta = 11.32 ± 0.25mg vs. S. xyloni = 6.40 ± 0.30mg) and produced over 50% as many eggs as S. xyloni. …

Reproductive Isolation And Differentiation Between Five Populations Of Cotesia Plutellae (Hymenoptera: Braconidae), Parasitoid Of Plutella Xylostella (Lepidoptera: Plutellidae), Claudia Rincon, Dominique Bordat, Bernhard Löhr, Stéphane Dupas

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Many taxa used in biological control may be composed of several population units reproductively isolated to various degrees. Yet, the introductions of non-compatible populations may result in a depression of intended biological control. Cotesia plutellae has been widely used as a biological control agent of the diamondback moth, Plutella xylostella. However, not all introductions and augmentations were successful. With the aim to develop markers of compatibility for this species, we studied the reproductive compatibility between five populations (South Africa, Benin, Martinique, Reunion, and Taiwan) and analyzed its statistical relationship with three morphological characters (antennae and body length and antennae/body ratio), …

Interspecific Competition Between Xanthopimpla Stemmator Thunberg And Dentichasmias Busseolae Heinrich (Hymenoptera: Ichneumonidae), Pupal Parasitoids Attacking Chilo Partellus (Lepidoptera: Crambidae) In East Africa, Benjamin K. Muli, Fritz Schulthess, Rosebella O. Maranga, Helen L. Kutima, Nanqing Jiang

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Interspecific competition between Xanthopimpla stemmator and Dentichasmias busseolae was studied using pupae of the invasive crambid stemborer Chilo partellus as the host. While X. stemmator is an old association, D. busseolae formed a relatively new association with C. partellus in East Africa. Two different time intervals between parasitism (0 and 48 h) and two parasitoid sequences [i.e., X. stemmator before D. busseolae (Xs-Db) and D. busseolae before X. stemmator (Db-Xs)] were chosen. In addition, the parasitoids' performance on pupae in maize stems and ears was assessed. For both X. stemmator and D. busseolae, there was no difference in foraging time …

Endothelial Cell Cortactin Coordinates Icam-1 Clustering And Actin Cytoskeleton Remodeling During Polymorphonuclear Leukocyte Adhesion And Transmigration, Jennifer Kowalski

Scholarship and Professional Work - LAS

Endothelial cell ICAM-1 interacts with leukocyte beta2 integrins to mediate adhesion and transmit outside-in signals that facilitate leukocyte transmigration. ICAM-1 redistribution and clustering appear necessary for leukocyte transmigration, but the mechanisms controlling ICAM-1 redistribution and clustering have not been identified. We recently reported that Src kinase phosphorylation of endothelial cortactin regulates polymorphonuclear cell (PMN) transmigration. In this study, we tested the hypotheses that the Src family kinase-cortactin pathway mediates association of ICAM-1 with the actin cytoskeleton and that this association is required for ICAM-1 clustering and leukocyte transmigration. Cross-linking ICAM-1 induced cytoskeletal remodeling and a decrease in ICAM-1 lateral mobility, …

2006 Nhep Implementation Review, Prep

PREP Reports & Publications

No abstract provided.

Oviposition Behavior Of Female Anopheles Gambiae In Eestern Kenya Inferred From Microsatellite Markers, Hong Chen, Ulrike Fillinger, Guiyun Yan

All Peer-Reviewed Publications

Anopheles gambiae females in a relatively isolated hut and all larvae from larval habitats within 100 m of the hut were collected in August 2001 in western Kenya. Among 42 aquatic habitats, 16 had A. gambiae larvae. Two hundred fifty larvae and 58 adults were genotyped using nine microsatellite markers to infer sibling relationship between the larvae and maternity between the females and larvae. The pairwise genetic relatedness of A. gambiae larvae per habitat ranged from -0.4112 to 0.9375, indicating that full siblings, half siblings, and genetically unrelated individuals presented at those habitats with multiple larvae. From a likelihood analysis, …

Molecular Characterization Of A Tsetse Fly Midgut Proteolytic Lectin That Mediates Differentiation Of African Trypanosomes, Laila U. Abubakar, Wallace D. Bulimo, Francis J. Mulaa, Ellie O. Osir

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Differentiation of bloodstream-form trypanosomes into procyclic (midgut) forms is an important first step in the establishment of an infection within the tsetse fly. This complex process is mediated by a wide variety of factors, including those associated with the vector itself, the trypanosomes and the bloodmeal. As part of an on-going project in our laboratory, we recently isolated and characterized a bloodmeal-induced molecule with both lectin and trypsin activities from midguts of the tsetse fly, Glossina longipennis [Osir, E.O., Abubakar, L., Imbuga, M.O., 1995. Purification and characterization of a midgut lectin-trypsin complex from the tsetse fly, Glossina longipennis. Parasitol. Res. …

New Bioassay Method To Assess The Pathogenicity Of Colombian Strains Of Metarhizium Anisopliae (Metsch.) Sorokin And Paecilomyces Sp. (Deuteromycotina: Hyphomycetes) Against The Subterranean Burrower Bug Cyrtomenus Bergi Froeschner (Hemiptera: Cydnidae), Juliana Jaramillo, Christian Borgemeister

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Using a new sand bioassay method, the pathogenicity of three Colombian strains of Metarhizium anisopliae (i.e., CIAT 224, 245, and 230) and one strain of Paecilomyces sp. (CIAT 308) were tested against fourth instars of the subterranean burrower bug Cyrtomenus bergi Froeschner (Hem.: Cydnidae) in the laboratory. The proposed bioassay simulates the habitat of C. bergi and at the same time enables the evaluation of a large number of insects in a short period of time and under controlled conditions. All tested fungal species/strains were pathogenic against C. bergi. However, only low levels of mortality were obtained, and never exceeded …

The Eggshell Structures Of Ringed Turtle - Doves (Streptopelia Risoria), Natalie Ellen Hubbard

Biology Theses - Archive

The avian egg provides nutrients and protects the growing embryo from physical and microbial harm. Structures fundamental to the protection are the membrane layers, which are tightly meshed networks of collagen fibers, and the eggshell, which is composed of calcite crystals, (CaC03). The eggs of Ringed Turtle-Dove and commercially bred chickens were selected for the study. Eggs of commercially bred chickens are twice in length and width of the dove eggs. Features analyzed are components of quality and strength of eggshells included shell thickness, membrane thickness, and concentration and size of vesicles. A comparative study of the bird eggs was …

Reproductive Behaviors Of Two Congeneric, Sympatric Jumping Spiders: Gene Flow Barriers And Polyandry, Stacey Nicole Gingras

Biology Theses - Archive

This two part study compares aspects of jumping spider reproductive behavior and their implications 1) as gene flow barriers during the process of speciation and 2) in the occurrence of polyandry. Courtship behaviors of Phidippus audax and P. carolinensis were observed. P. carolinensis displays simple courtship behavior when compared to the visually complex behavior of P. audax. P. carolinensis males appear to be incorporating a vibratory element into their courtship display, and a possible stridulatory organ, located on the male pedipalp, is described. Large differences in courtship display, complexity of courtship badges, and phenologies between the species most likely prevent …

Study Of The Expression Pattern Of A Possible Pseudogene And A Functional Retrogene In Drosophila, Aditi Bhardwaj

Biology Theses - Archive

Gene duplication occurs when a mutation leads to the copying of a region of DNA that contains a functional gene. After duplication, there will be two copies of the gene in the genome. Gene duplication can have deleterious effects but it can also be the source of novelty. It has been acknowledged for a long time that selection may be relaxed for one copy rendering that locus free to mutate and discover new functions. Another of the fates of duplication of special notice is the formation of a pseudogene. Pseudogenes have been defined as nonfunctional sequences of genomic DNA originally …

Incidence Of Larval And Pupal Parasitoids Of Lepidoptera In Uganda With Special Reference To New Associations, I. Rwomushana, S. Kyamanywa, A. J. Ngi-Song, C. O. Omwega

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Cotesia flavipes Cameron (Hymenoptera: Braconidae) was introduced in Uganda in 1998 for the biological control of the old association cereal stemborer Chilo partellus (Swinhoe) (Lepidoptera: Crambidae). However there is little information on whether this parasitoid will attack new association Lepidoptera, which in turn may have implications on its efficacy on Ch. partellus. This study investigated the incidence of introduced Co. flavipes on Ch. partellus, and new association lepidopteran species and associated effects on its efficacy. Parasitism levels for Co. flavipes in several locations varied between 13.7-34.8% and 1.5-18.8% on Ch. partellus and new association hosts, respectively. Implications for biological control …

Variations In Races Of The Honeybee Apis Mellifera (Hymenoptera: Apidae) In Kenya, S. K. Raina, D. M. Kimbu

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The three races of the honeybee Apis mellifera Linnaeus in Kenya (A. m. scutellata, A. m. monticola and A. m. litorea) differ from each other with respect to size, cubital index and abdominal colour banding pattern. These differences were used to assess the extent of interbreeding and hybridization between the races. This was verified on the basis of selected morphometric traits. Bee samples were collected from traditional log hives in seven geographical locations throughout Kenya ranging from lowland Mombasa in the coastal region to the highland Kinangop ranges. The length and width of the right forewing, length of proboscis, right …

The Effect Of Nitrogen Fertilizer Application To Maize And Sorghum On The Bionomics Of Chilo Partellus (Lepidoptera: Crambidae) And The Performance Of Its Larval Parasitoid Cotesia Flavipes (Hymenoptera: Braconidae), N. Jiang, F. Schulthess

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Laboratory and field trials were conducted to evaluate the effect of plant species (maize, sorghum), plant age (young, middle, old) and four different nitrogen fertilization levels (N0-N3) on the bionomics of the invasive crambid Chilo partellus and the performance of its braconid larval parasitoid Cotesia flavipes. Plant N varied significantly between N0 and N1-N3, but the differences among the latter were not significant. Intrinsic rates of increase and net-reproductive rates of C. partellus followed the same trends: they were lowest with N0 and similar among the other treatments. On maize only, mortality of C. partellus and parasitism by C. flavipes …

Relationships Of Intercropped Maize, Stem Borer Damage To Maize Yield And Land-Use Efficiency In The Humid Forest Of Cameroon, A. Chabi-Olaye, C. Nolte, F. Schulthess, C. Borgemeister

All Peer-Reviewed Publications

Stem borers are the most important maize pests in the humid forest zone of Cameroon. Field trials were conducted in the long and short rainy seasons of 2002 and 2003 to assess the level of damage and yield reductions caused by stem borers in monocropped maize and in maize intercropped with non-host plants such as cassava, cowpea and soybean. The intercrops were planted in two spatial arrangements, i.e. alternating hills or alternating rows. All intercrops and the maize monocrop were grown with and without insecticide treatment for assessment of maize yield loss due to borer attacks. The land-use efficiency of …

Fitness Consequences Of Anopheles Gambiae Population Hybridization, David M. Menge, Tom Guda, Daibin Zhong, Aditi Pai, Goufa Zhou, John C. Beier, Louis Gouagna, Guiyun Yan

All Peer-Reviewed Publications

Background: The use of transgenic mosquitoes with parasite inhibiting genes has been proposed as an integral strategy to control malaria transmission. However, release of exotic transgenic mosquitoes will bring in novel alleles along with parasite-inhibiting genes that may have unknown effects on native populations. Thus it is necessary to study the effects and dynamics of fitness traits in native mosquito populations in response to the introduction of novel genes. This study was designed to evaluate the dynamics of fitness traits in a simulation of introduction of novel alleles under laboratory conditions using two strains of Anopheles gambiae: Mbita strain from …

Termite (Isoptera) Diversity In Senegal And Their Damage On Reforestation Areas And Cultures, Makhfousse Sarr, Nguya K. Maniania, A. Russell-Smith, Abdoulaye Niassy

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Studies conducted from 1969 to 2000 on termite ecology and biology in Senegal revealed high termite diversity and an influence of climate and soil conditions on termite group distribution. Sixty-four termite species were recorded. Some were specific to ecologically similar zones while others were widely distributed. Some species, known to inhabit wet zones, were found in semi-arid zones where relic forest vegetation still exists. Nioro, in the central part of the country, seems to be the buffer zone between species to the north and south of Senegal. In Ferlo, an arid zone, Macrotermes species was in regression and the subsisting …

The Effect Of Host Larvae On Three Psyttalia Species (Hymenoptera: Braconidae), Parasitoids Of Fruit-Infesting Flies (Diptera: Tephritidae), M. K. Billah, S. Kimani-Njogu, W. A. Overholt, R. A. Wharton, D. D. Wilson, M. A. Cobblah

All Peer-Reviewed Publications

Three species of fruit fly parasitoids, Psyttalia concolor (Szépligeti), Psyttalia cosyrae (Wilkinson) and Psyttalia lounsburyi (Silvestri) (Hymenoptera: Braconidae) were reared on different host larvae to determine the effects of host species, size and colour on parasitoid development. Ovipositor, ovipositor sheath and hind tibia lengths were found to be different for progenies from preferred and non-preferred host larvae. Ratios of ovipositor-tibia and ovipositor sheath-tibia showed no difference when P. concolor was reared on a bigger host (Ceratitis cosyra (Walker) (Diptera: Tephritidae), whereas rearing P. cosyrae on a smaller host (C. capitata (Wiedemann) showed significant differences. Comparison of the linear measurements, ratios …

Repellency Of Essential Oils Of Some Plants From The Kenyan Coast Against Anopheles Gambiae, Josiah O. Odalo, Maurice O. Omolo, Hamisi Malebo, John Angira, Patrick M. Njeru, Isaiah O. Ndiege, Ahmed Hassanali

All Peer-Reviewed Publications

Volatile oils extracted by hydrodistillation from six plant species growing in the Kenyan coast, Croton pseudopulchellus Pax, Mkilua fragrans Verdc. (Annonaceae), Endostemon tereticaulis (poir.) Ashby, Ocimum forskolei Benth., Ocimum fischeri Guerke and Plectranthus longipes Baker (Labiateae), were evaluated for repellency on forearms of human volunteers against Anopheles gambiae sensu stricto. All oils were found to be more repellent (RC50 range = 0.67-9.21 × 10-5 mg cm-2) than DEET (RC50 = 33 × 10-5 mg cm-2). The individual components of the oils were identified by GC-MS and GC co-injections with authentic standards. The repellency of 15 of the main constituents of …

Feasibility For Utilization Of A Freshwater Pulmonate Snail, Physa Acuta, As A Model Organism For Environmental Toxicity Testing, With Special Reference To Cadmium Ion Toxicity, Valerie Woodard

Biology Dissertations - Archive

The benefits of developing the pond snail, Physa acuta, as a model species for testing acute and chronic toxicity of aquatic pollutants include its wide North American distribution, ease of field collection and laboratory maintenance, and efficacy in testing toxicity responses including mortality, crawling behavior, reproduction and metabolism under both field and laboratory conditions. Mortality, as 50 % sample lethal concentration (LC50) and 50 % sample lethal time (LT50) values with increased cadmium chloride (CdCl2) concentration in both acute 192 h and chronic 672 h tests. A new endpoint of 50 % sample crawl-out response (CO50) proved to be a …