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Articles 2131 - 2160 of 2421

Full-Text Articles in Life Sciences

Genetic Diversity In Cowpea [Vigna Unguiculata (L.) Walp.] As Revealed By Rapd Markers, Fana Sylla Ba, Remy S. Pasquet, Paul Gepts Aug 2004

Genetic Diversity In Cowpea [Vigna Unguiculata (L.) Walp.] As Revealed By Rapd Markers, Fana Sylla Ba, Remy S. Pasquet, Paul Gepts

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The present study, using RAPD analysis, was undertaken to characterize genetic variation in domesticated cowpea and its wild progenitor, as well as their relationships. The materials used consisted of 26 domesticated accessions, including accessions from each of the five cultivar-group, and 30 wild/weedy accessions, including accessions from West, East and southern Africa. A total of 28 primers generated 202 RAPD bands. One hundred and eight bands were polymorphic among the domesticated compared to 181 among wild/weedy cowpea accessions. Wild accessions were more diverse in East Africa, which is the likely area of origin of V. unguiculata var. spontanea. Var. spontanea …

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Multi-Trophic Level Interactions In A Cassava-Maize Mixed Cropping System In The Humid Tropics Of West Africa, F. Schulthess, A. Chabi-Olaye, S. Gounou Jun 2004

Multi-Trophic Level Interactions In A Cassava-Maize Mixed Cropping System In The Humid Tropics Of West Africa, F. Schulthess, A. Chabi-Olaye, S. Gounou

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Multi-trophic level interactions in a mixed crop, involving cassava and maize, were studied in derived-savanna in Benin, West Africa. Two trials were planted, one during the short rainy season two months before onset of the dry season and one during the long rainy season in spring. Key pests under study on maize were the noctuid Sesamia calamistis Hampson and the pyralids Eldana saccharina Walker and Mussidia nigrivenella Ragonot, and on cassava, the exotic mealybug, Phenacoccus manihoti Matile-Ferrero and its encyrtid parasitoid Apoanagyrus lopezi De Santis. Both crops received insecticide treatments to assess the crop loss by a pest species. On …

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Diabetes Stepping Up To The Plate: An Education Curriculum Focused On Food Portioning Skills, D. Pauline Williams, Heidi Leblanc, Nedra K. Christensen Jun 2004

Diabetes Stepping Up To The Plate: An Education Curriculum Focused On Food Portioning Skills, D. Pauline Williams, Heidi Leblanc, Nedra K. Christensen

Nutrition, Dietetics, and Food Sciences Faculty Publications

The Diabetes Stepping up to the Plate program was developed to determine the effectiveness of food portion based diabetes education. One hundred fifty-one individuals enrolled in the diabetes series. Food portion knowledge and skills tests, height, weight, and waist-to-hip ratio (WHR) were measured pre- and post-program. Data was analyzed through paired t-tests and correlations. Evaluation showed a decrease in HbA1C, waist/hip circumference, WHR, and BMI, and an improvement in food portion knowledge and skills. Seventy-five participants completed pre- and post-data collection parameters, although more participants completed all classes in the series. Extension can play a role in successful diabetes education.

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Characterization Of Potential Larval Habitats For Anopheles Mosquitoes In Relation To Urban Land-Use In Melindi, Kenya, Joseph Keating, Kate Macintyre, Charles M. Mbogo, John I. Githure, John C. Beier May 2004

Characterization Of Potential Larval Habitats For Anopheles Mosquitoes In Relation To Urban Land-Use In Melindi, Kenya, Joseph Keating, Kate Macintyre, Charles M. Mbogo, John I. Githure, John C. Beier

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Background: This study characterized Anopheles mosquito larval habitats in relation to ecological attributes about the habitat and community-level drainage potential, and investigated whether agricultural activities within or around urban households increased the probability of water body occurrence. Malindi, a city on the coast of Kenya, was mapped using global positioning system (GPS) technology, and a geographic information system (GIS) was used to overlay a measured grid, which served as a sampling frame. Grid cells were stratified according to the level of drainage in the area, and 50 cells were randomly selected for the study. Cross-sectional household and entomological surveys were …

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Comparative Studies On The Infectivity Of Theileria Parva In Ticks Fed In Vitro And Those Fed On Cattle, Joseph M. Musyoki, Ellie O. Osir, Henry K. Kiara, Elizabeth D. Kokwaro Apr 2004

Comparative Studies On The Infectivity Of Theileria Parva In Ticks Fed In Vitro And Those Fed On Cattle, Joseph M. Musyoki, Ellie O. Osir, Henry K. Kiara, Elizabeth D. Kokwaro

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Nymphs of the brown ear tick, Rhipicephalus appendiculatus, were fed on heparinised bovine blood infected with Theileria parva parasites in an in vitro feeding system consisting of rabbit skin membranes. The main feeding and development parameters such as the mean attachment rate, feeding duration and engorgement weights of membrane-fed ticks were not significantly different from nymphs fed on cattle. The moulting rate was also comparable although a slight significant difference was observed. Assessment of infection prevalence and abundance with T. parva in adults indicated that the membrane-fed ticks acquired infection to the same level as those fed on cattle. Stabilates …

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Patterns Of Feline Immunodeficiency Virus Multiple Infection And Genome Divergence In A Free-Ranging Population Of African Lions, Jennifer L. Troyer, Jill Pecon-Slattery, Melody E. Roelke, Lori Black, Craig Packer, Stephen J. O'Brien Apr 2004

Patterns Of Feline Immunodeficiency Virus Multiple Infection And Genome Divergence In A Free-Ranging Population Of African Lions, Jennifer L. Troyer, Jill Pecon-Slattery, Melody E. Roelke, Lori Black, Craig Packer, Stephen J. O'Brien

Biology Faculty Articles

Feline immunodeficiency virus (FIV) is a lentivirus that causes AIDS-like immunodeficiency disease in domestic cats. Free-ranging lions, Panthera leo, carry a chronic species-specific strain of FIV, FIV-Ple, which so far has not been convincingly connected with immune pathology or mortality. FIV-Ple, harboring the three distinct strains A, B, and C defined by pol gene sequence divergences, is endemic in the large outbred population of lions in the Serengeti ecosystem in Tanzania. Here we describe the pattern of variation in the three FIV genes gag, pol-RT, and pol-RNase among lions within 13 prides to assess the occurrence of FIV infection and …

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Seroprevalence Of Bartonella Infection In American Free-Ranging And Captive Pumas (Felis Concolor) And Bobcats (Lynx Rufus), Bruno B. Chomel, Yoko Kikuchi, Janice S. Martenson, Melodie E. Roelke-Parker, Chao Chin Chang, Rickie W. Kasten, Janet E. Foley, John Laudre, Kerry Murphy, Pamela K. Swift, Vicki L. Kramer, Stephen J. O'Brien Mar 2004

Seroprevalence Of Bartonella Infection In American Free-Ranging And Captive Pumas (Felis Concolor) And Bobcats (Lynx Rufus), Bruno B. Chomel, Yoko Kikuchi, Janice S. Martenson, Melodie E. Roelke-Parker, Chao Chin Chang, Rickie W. Kasten, Janet E. Foley, John Laudre, Kerry Murphy, Pamela K. Swift, Vicki L. Kramer, Stephen J. O'Brien

Biology Faculty Articles

Bartonella henselae is the main agent of cat scratch disease in humans and domestic cats are the main reservoir of this bacterium. We conducted a serosurvey to investigate the role of American wild felids as a potential reservoir of Bartonella species. A total of 479 samples (439 serum samples and 40 Nobuto strips) collected between 1984 and 1999 from pumas (Felis concolor) and 91 samples (58 serum samples and 33 Nobuto strips) collected from bobcats (Lynx rufus) in North America, Central America and South America were screened for B. henselae antibodies. The overall prevalence of B. henselae antibodies was respectively …

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Effect Of Sucrose Esters On The Crystallization Behavior Of Bulk Oil Systems, Silvana Martini, M. Cerdeira, M. L. Herrera Feb 2004

Effect Of Sucrose Esters On The Crystallization Behavior Of Bulk Oil Systems, Silvana Martini, M. Cerdeira, M. L. Herrera

Nutrition, Dietetics, and Food Sciences Faculty Publications

Sucrose esters (SE) of FA can be used in foods as emulsifiers because they are nontoxic, tasteless, odorless, and are digested to sucrose and FA in the stomach. They can also be used in pharmaceuticals and cosmetics and in other products where a nonionic, nontoxic, biodegradable emulsifier is required. In addition to their major function of producing and stabilizing emulsions, SE have numerous other functional roles as texturizers, film formers, and modifiers of bulk-phase crystallization behavior (with bulk phase meaning a homogeneous oil phase). A few reports have dealt with the effect of SE on the crystallization behavior of fats …

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Effect Of Constant Temperatures On Germination, Radial Growth And Virulence Of Metarhizium Anisopliae To Three Species Of African Tephritid Fruit Flies, Susan Dimbi, Nguya K. Maniania, Slawomir A. Lux, Jones M. Mueke Feb 2004

Effect Of Constant Temperatures On Germination, Radial Growth And Virulence Of Metarhizium Anisopliae To Three Species Of African Tephritid Fruit Flies, Susan Dimbi, Nguya K. Maniania, Slawomir A. Lux, Jones M. Mueke

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The effect of temperature on conidial germination, mycelial growth, and susceptibility of adults of three tephritid fruit flies, Ceratitis capitata (Wiedemann), C. fasciventris (Bezzi) and C. cosyra (Walker) to six isolates of Metarhizium anisopliae were studied in the laboratory. There were significant differences among the isolates in the effect of temperature on both germination and growth. Over 80% of conidia germinated at 20, 25 and 30°C, while between 26 and 67% conidia germinated at 35°C and less than 10% at 15°C within 24 hours. Radial growth was slow at 15°C and 35°C with all of the isolates. The optimum temperature …

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Host Suitability And Thermal Requirements Of Lathromeris Ovicida Risbec (Hymenoptera: Tricliogrammatidae), An Egg Parasitoid Of Cereal Stemborers In Africa, A. Chabi-Olaye, M. K. Fiaboe, F. Schulthess Jan 2004

Host Suitability And Thermal Requirements Of Lathromeris Ovicida Risbec (Hymenoptera: Tricliogrammatidae), An Egg Parasitoid Of Cereal Stemborers In Africa, A. Chabi-Olaye, M. K. Fiaboe, F. Schulthess

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Factors affecting the bionomics of the trichogrammatid egg parasitoid Lathromeris ovicida and its association with the two sympatric scelionid egg parasitoids Telenomus busseolae and Telenomus isis were studied in the laboratory. The potential host species employed were the noctuids Sesamia calamistis and Sesamia botanephaga, and the pyralids Eldana saccharina and Mussidia nigrivenella. Using eggs of S. calamistis Hampson as hosts, the lower and upper thresholds for development were estimated at 14.8 and 34°C, respectively. The percent parasitism, total progeny, and sex ratio decreased gradually from 42.0 to 10.2, from 56.4 to 10.8, and from 0.74 to 0.61, respectively, with host …

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Phylogeny And Biogeography Of Wajira (Leguminosae): A Monophyletic Segregate Of Vigna Centered In The Horn Of Africa Region, Mats Thulin, Matt Lavin, Remy Pasquet, Alfonso Delgado-Salinas Jan 2004

Phylogeny And Biogeography Of Wajira (Leguminosae): A Monophyletic Segregate Of Vigna Centered In The Horn Of Africa Region, Mats Thulin, Matt Lavin, Remy Pasquet, Alfonso Delgado-Salinas

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Evidence from chloroplast trnK and nuclear ribosomal ITS sequences and morphological data reveals that the monotypic legume genus Wajira is nested within a clade comprising the species of Vigna subgen. Macrorhynchus. This Wajira-containing clade is basally branching in a larger clade that contains many of the genera traditionally referred to as tribe Phaseoleae subtribe Phaseolinae. Wajira is thus recircumscribed to include Vigna subgen. Macrorhynchus. Given the heterogeneity of floral morphology of its constituent species, Wajira is apomorphically diagnosed by woody stems and a pollen brush that comprises an introrse linear array of unicellular hairs. This recircumscribed genus now comprises five …

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Effects Of Salts On Crystallization Kinetics And Rheological Behavior Of Concentrated , -Trehalose Solutions, Marina Cerdeira, M. C. Puppo, Silvana Martini, M. L. Herrera Nov 2003

Effects Of Salts On Crystallization Kinetics And Rheological Behavior Of Concentrated , -Trehalose Solutions, Marina Cerdeira, M. C. Puppo, Silvana Martini, M. L. Herrera

Nutrition, Dietetics, and Food Sciences Faculty Publications

The effect of addition of CaCl2 2H2O and MgCl2 6H2O on crystallization kinetics and the rheological behavior of a 70% trehalose solution was studied by polarized light microscopy and dynamic oscillatory rheometry. Salts caused a delay on nucleation with induction times for crystallization longer for Mg2+ than for Ca2+. Divalent cations were incorporated into crystals, changing the growth of certain faces preferentially, which resulted in changes in morphology. Addition of CaCl2 2H2O in a high salt/trehalose molar ratio dramatically increased complex modulus (G*), indicating a stronger viscoelastic behavior. A gel-like structure was formed when Ca2+ was added to trehalose solution. …

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Host Species, Age And Sex As Factors Affecting The Susceptibility Of The African Tephritid Fruit Fly Species, Ceratitis Capitata, C. Cosyra And C. Fasciventris To Infection By Metarhizium Anisopliae, S. Dimbi, N. K. Maniania, S. A. Lux, J. M. Mueke Oct 2003

Host Species, Age And Sex As Factors Affecting The Susceptibility Of The African Tephritid Fruit Fly Species, Ceratitis Capitata, C. Cosyra And C. Fasciventris To Infection By Metarhizium Anisopliae, S. Dimbi, N. K. Maniania, S. A. Lux, J. M. Mueke

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The effect of host age and sex on the susceptibility of 3 tephritid fruit fly species, Ceratitis capitata (Wiedemann), C. cosyra (Walker) and C. fasciventris (Bezzi) to the entomopathogenic fungus Metarhizium anisopliae (Metchnikoff) Sorokin was studied in the laboratory. Three adult host ages, 0 (<1 day-old), 7-day-old and 14-day-old, were used. All 3 species were susceptible to fungal infection, although there were differences in the levels of susceptibility among the hosts. Age accounted for the largest variability in mortality followed by species, while sex had the lowest variability. Of the 3 host ages tested, the 0- and 7-day-old flies were more susceptible to fungal infection than the 14-day-old flies. Male and female C. fasciventris flies generally succumbed earlier to fungal infection than the other two species. Female flies of C. cosyra and C. fasciventris were also generally more susceptible to fungal infection than the males, although differences were apparent at 3 and 4 days after treatment but not 5 days after treatment. Age accounted for the largest variability in lethal time mortality values (LTs). Mean LT-values generally indicated that the speed of kill was faster among younger flies than the older flies. LT95 ranged between 3.9-4.9 days in the 0-day-old flies, 4.3-6.1 days in the 7-day-old flies and 4.6-6.1 days in 14-day-old flies in the different species and sexes. The implication of this study for the management of fruit flies is discussed.

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Responses Of Glossina Morsitans Morsitans To Blends Of Electroantennographically Active Compounds In The Odors Of Its Preferred (Buffalo And Ox) And Nonpreferred (Waterbuck) Hosts, Nicholas K. Gikonyo, Ahmed Hassanali, Peter G.N. Njagi, Rajinder K. Saini Oct 2003

Responses Of Glossina Morsitans Morsitans To Blends Of Electroantennographically Active Compounds In The Odors Of Its Preferred (Buffalo And Ox) And Nonpreferred (Waterbuck) Hosts, Nicholas K. Gikonyo, Ahmed Hassanali, Peter G.N. Njagi, Rajinder K. Saini

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In a previous study, comparison of the behavior of teneral Glossina morsitans morsitans on waterbuck, Kobus defassa (a refractory host), and on two preferred hosts, buffalo, Syncerus caffer, and ox, Bos indicus, suggested the presence of allomones in the waterbuck odor. Examination of the volatile odors by coupled gas chromatography-electroantennographic detection showed that the antennal receptors of the flies detected constituents common to the three bovids (phenols and aldehydes), as well as a series of compounds specific to waterbuck, including C8 - C13 methyl ketones, δ-octalactone, and phenols. In this study, behavioral respones of teneral G. m. morsitans to different …

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Effect Of Sucrose Ester Addition On Nucleation And Growth Behavior Of Milk Fat-Sunflower Oil Blends, Marina Cerdeira, Silvana Martini, Richard W. Hartel, Maria Lidia Herrera Sep 2003

Effect Of Sucrose Ester Addition On Nucleation And Growth Behavior Of Milk Fat-Sunflower Oil Blends, Marina Cerdeira, Silvana Martini, Richard W. Hartel, Maria Lidia Herrera

Nutrition, Dietetics, and Food Sciences Faculty Publications

The effects of addition of the sucrose esters (SE) P-1670, P-170, and S-170 to a high-melting fraction of milk fat (HMF) and its blends with sunflower oil (SFO) on nucleation and growth were studied by laser polarized light turbidimetry and polarized light microscopy (PLM). The three SE delayed nucleation of HMF at the temperatures selected. P-1670 did not modify average crystal size after 3 h at crystallization temperature (Tc) or crystal size distribution and modified crystallization kinetics only slightly. P-170 and S-170, however, markedly diminished crystal size and narrowed crystal size distribution. Activation free energies of nucleation at equivalent supercooling, …

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Parameter Estimation For Distributed Delay Based Population Models From Laboratory Data: Egg Hatching Of Oulema Duftschmidi Redthenbacher (Coleoptera, Chrysomelidae) As An Example, Maurizio Severini, Johann Baumgärtner, Lidia Limonta Sep 2003

Parameter Estimation For Distributed Delay Based Population Models From Laboratory Data: Egg Hatching Of Oulema Duftschmidi Redthenbacher (Coleoptera, Chrysomelidae) As An Example, Maurizio Severini, Johann Baumgärtner, Lidia Limonta

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The cohort development of poikilotherms under favorable temperature conditions may be described by the time-invariant distributed delay models that require three parameters, i.e. the thermal threshold T0, the thermal constant W and the variability parameter H representing distributed maturation times, also known as time distributed or stochastic development. Here, a parsimonious method is developed that uses stage-frequency matrices obtained under controlled conditions. The analysis of these matrices permits the estimation of the three parameters, while the incorporation of both developmental threshold and thermal constant into the time-invariant distributed delay model permits the representation of stochastic cohort development under constant temperatures. …

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Crystallization Of Sunflower Oil Waxes, Silvana Martini, M. C. Anon Jun 2003

Crystallization Of Sunflower Oil Waxes, Silvana Martini, M. C. Anon

Nutrition, Dietetics, and Food Sciences Faculty Publications

Activation free energies of nucleation (ΔG c ) were calculated using induction times of crystallization measurements. Results showed that ΔG c decreased exponentially as wax concentration increased at a constant crystallization temperature (T c ). In contrast, for a constant supersaturation, ΔG c increased from 12 to 22°C but decreased between 22 and 35°C. Melting behavior of purified waxes and solutions of purified waxes in sunflower oil were studied by DSC after crystallization at fast and slow cooling rates (20 and 1°C/min, respectively). Low supercooling temperatures (T c >65°C) showed an increase in the onset temperature (T 0 ) as …

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Effect Of Soil Temperature And Moisture On Survival And Infectivity Of Metarhizium Anisopliae To Four Tephritid Fruit Fly Puparia, S. Ekesi, N. K. Maniania, S. A. Lux Jun 2003

Effect Of Soil Temperature And Moisture On Survival And Infectivity Of Metarhizium Anisopliae To Four Tephritid Fruit Fly Puparia, S. Ekesi, N. K. Maniania, S. A. Lux

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The infectivity of 4 isolates of Metarhizium anisopliae to puparia of Ceratitis capitata treated as late third-instar larvae in unsterilized soil was investigated in the laboratory under controlled temperature and moisture. At 20-30°C, mortality in puparia was highest at water potential of -0.1 and -0.01 mega Pascal (MPa) and lowest at water potential of -0.0055 and -0.0035 MPa in all the isolates. In wetter soil however, isolates ICIPE 20 and 60 caused significantly higher mortality than ICIPE 18 and 69. The survival of conidia in drier soil (-0.1 MPa) was not adversely affected at all temperatures. However, in wet soil …

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Crop Damage By Nematodes In Improved-Fallow Fields In Western Kenya, Serigne T. Kandji, Callistus K.P.O. Ogol, Alain Albrecht May 2003

Crop Damage By Nematodes In Improved-Fallow Fields In Western Kenya, Serigne T. Kandji, Callistus K.P.O. Ogol, Alain Albrecht

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The rotation of leguminous shrubs and crops is being tested on farms and recommended as a means of improving soil fertility and increasing crop yield in eastern and southern Africa, including western Kenya. However, this improved fallow practice may also increase the nematode population in the soil. An experiment was conducted to monitor the effects of plant-parasitic nematodes on crops after improved fallow. Soil was collected from a maize (Zea mays L.)/bean (Phaseolus vulgaris L.) field, a natural fallow, a Crotalaria (Crotalaria grahamiana Wight & Am.) fallow, a Tephrosia (Tephrosia vogelii Hook. f.) fallow and a Crotalaria - Tephrosia mixed …

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Utilizing Non-Fat Dried Milk In Sheep, C. Kim Chapman May 2003

Utilizing Non-Fat Dried Milk In Sheep, C. Kim Chapman

All Current Publications

No abstract provided.

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Prevented Planting, Unknown Unknown Apr 2003

Prevented Planting, Unknown Unknown

All Current Publications

No abstract provided.

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Evidence Of The Establishment Of Cotesia Flavipes (Hymenoptera: Braconidae), A Parasitoid Of Cereal Stemborers, And Its Host Range Expansion In Ethiopia, E. Getu, W. A. Overholt, E. Kairu, C. O. Omwega Apr 2003

Evidence Of The Establishment Of Cotesia Flavipes (Hymenoptera: Braconidae), A Parasitoid Of Cereal Stemborers, And Its Host Range Expansion In Ethiopia, E. Getu, W. A. Overholt, E. Kairu, C. O. Omwega

All Peer-Reviewed Publications

Three lepidopteran cereal stemborers, Chilo partellus (Swinhoe) (Crambidae), Busseola fusca Fuller, and Sesamia calamistis Hampson (Noctuidae) were collected from maize and sorghum in Ethiopia. The noctuid stemborers are indigenous to Africa while C. partellus is an introduced species from Asia. In 1999, the Asian stemborer parasitoid, Cotesia flavipes Cameron (Braconidae) was found to be widespread in Ethiopia, even though it had never been released in the country. In addition to attacking Chilo partellus, Cotesia flavipes was reared from B. fusca and S. calamistis. The origin of C. flavipes in Ethiopia may have been Somalia where it was released in 1997 …

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Effects Of Molasses Grass, Melinis Minutiflora Volatiles On The Foraging Behavior Of The Cereal Stemborer Parasitoid, Cotesia Sesamiae, Linnet S. Gohole, William A. Overholt, Zeyaur R. Khan, John A. Pickett, Louise E.M. Vet Mar 2003

Effects Of Molasses Grass, Melinis Minutiflora Volatiles On The Foraging Behavior Of The Cereal Stemborer Parasitoid, Cotesia Sesamiae, Linnet S. Gohole, William A. Overholt, Zeyaur R. Khan, John A. Pickett, Louise E.M. Vet

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Olfactory responses of the cereal stemborer parasitoid Cotesia sesamiae to volatiles emitted by gramineous host and nonhost plants of the stemborers were studied in a Y-tube olfactometer. The host plants were maize (Zea mays) and sorghum (Sorghum bicolor), while the nonhost plant was molasses grass (Melinis minutiflora). In single-choice tests, females of C. sesamiae chose volatiles from infested and uninfested host plants and molasses grass over volatiles from the control (soil). In dual-choice tests, the wasp preferred volatiles from infested host plants to those from uninfested host plants. There was no discrimination between molasses grass volatiles and those of uninfested …

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Incomplete Sexual Isolation In Sympatry Between Subspecies Of The Butterfly Danaus Chrysippus (L.) And The Creation Of A Hybrid Zone, G. Lushai, D. A.S. Smith, I. J. Gordon, D. Goulson, J. A. Allen, N. Maclean Mar 2003

Incomplete Sexual Isolation In Sympatry Between Subspecies Of The Butterfly Danaus Chrysippus (L.) And The Creation Of A Hybrid Zone, G. Lushai, D. A.S. Smith, I. J. Gordon, D. Goulson, J. A. Allen, N. Maclean

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Subspecies chrysippus, dorippus and alcippus of the butterfly Danaus chrysippus differ at three biallelic colour gene loci. They have partially vicariant distributions, but their ranges overlap over a substantial part of central and East Africa, where hybridism is commonplace. We now report that the West African subspecies alcippus differs from other subspecies, not only in nuclear genotype but also in mitochondrial haplotype in both allopatry and sympatry. The maintenance of concordant nuclear and cytoplasmic genetic differences in sympatry, and in the face of hybridisation, is prima facie evidence for sexual isolation. Other evidence that suggests alcippus may be isolated from …

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Enrichment Of A Single Clone From A High Diversity Library Of Phage-Displayed Antibodies By Panning With Anopheles Gambiae (Diptera: Culicidae) Midgut Homogenate, G. F. Killeen, B. D. Foy, R. H. Frohn, D. Impoinvil, A. Williams, J. C. Beier Feb 2003

Enrichment Of A Single Clone From A High Diversity Library Of Phage-Displayed Antibodies By Panning With Anopheles Gambiae (Diptera: Culicidae) Midgut Homogenate, G. F. Killeen, B. D. Foy, R. H. Frohn, D. Impoinvil, A. Williams, J. C. Beier

All Peer-Reviewed Publications

A high diversity library of recombinant human antibodies was selected on complex antigen mixtures from midguts of female Anopheles gambiae Giles. The library of phage-displayed single chain variable region fragment constructs, derived from β-lymphocyte mRNA of naïve human donors, was repeatedly selected and reamplified on the insoluble fraction of midgut homogenates. Five rounds of panning yielded only one midgut-specific clone, which predominated the resulting antibody panel. In A. gambiae, the epitope was found throughout the tissues of females but was absent from the midgut of males. The cognate antigen proved to be detergent soluble but very sensitive to denaturation and …

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Comparative Analysis Of Microsatellite Loci In Four Fruit Fly Species Of The Genus Ceratitis (Diptera: Tephritidae), F. N. Baliraine, M. Bonizzoni, E. O. Osir, S. A. Lux, F. J. Mulaa, L. Zheng, L. M. Gomulski, G. Gasperi, A. R. Malacrida Feb 2003

Comparative Analysis Of Microsatellite Loci In Four Fruit Fly Species Of The Genus Ceratitis (Diptera: Tephritidae), F. N. Baliraine, M. Bonizzoni, E. O. Osir, S. A. Lux, F. J. Mulaa, L. Zheng, L. M. Gomulski, G. Gasperi, A. R. Malacrida

All Peer-Reviewed Publications

The possibility to cross-species amplify microsatellites in fruit flies of the genus Ceratitis was tested with the polymerase chain reaction (PCR) by analysing 23 Ceratitis capitata (Wiedemann) microsatellite markers on the genomic DNA of three other economically important, congeneric species: C. rosa (Karsch), C. fasciventris (Bezzi) and C. cosyra (Walker). Twenty-two primer pairs produced amplification products in at least one of the three species tested. The majority of the products were similar, if not identical in size to those expected in C. capitata. The structures of the repeat motifs and their flanking sequences were examined for a total of 79 …

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High Seasonal Variation In Entomologic Inoculation Rates In Eritrea, A Semi-Arid Region Of Unstable Malaria In Africa, Josephat Shililu, Tewolde Ghebremeskel, Solomon Mengistu, Helen Fekadu, Mehari Zerom, Charles Mbogo, John Githure, Robert Novak, Eugene Brantly, John C. Beier Jan 2003

High Seasonal Variation In Entomologic Inoculation Rates In Eritrea, A Semi-Arid Region Of Unstable Malaria In Africa, Josephat Shililu, Tewolde Ghebremeskel, Solomon Mengistu, Helen Fekadu, Mehari Zerom, Charles Mbogo, John Githure, Robert Novak, Eugene Brantly, John C. Beier

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Entomologic studies were conducted in eight villages to investigate the patterns of malaria transmission in different ecologic zones in Eritrea. Mosquito collections were conducted for 24 months between September 1999 and January 2002. The biting rates of Anopheles arabiensis were highly seasonal, with activity concentrated in the wet season between June and October in the highlands and western lowlands, and between December and March in the coastal region. The biting rates in the western lowlands were twice as high as in the western escarpment and 20 times higher than in the coastal region. Sporozoite rates were not significantly different among …

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Integrated Arthropod Pest Management Systems For Human Health Improvement In Africa, Johann Baumgärtner, Fritz Schulthess, Yunlong Xia Jan 2003

Integrated Arthropod Pest Management Systems For Human Health Improvement In Africa, Johann Baumgärtner, Fritz Schulthess, Yunlong Xia

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In a sub-Saharan African context, limited natural resources, infectious diseases, including those transmitted by arthropod vectors, and chronic exposure to food contaminated with mycotoxin-producing fungi which, among others, are vectored by insects, are among the major constraints to human health. Thus, pest control should be an important component in human health improvement projects. It appears that the advantages of preventive over curative methods are rarely recognised in Africa, with more emphasis being given to the search for the 'silver bullet' than to integrated control approaches. Integrated pest management (IPM) systems can be assigned to different decision-making levels as well as …

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Isoflavanones From The Allelopathic Aqueous Root Exudate Of Desmodium Uncinatum, Muniru K. Tsanuo, Ahmed Hassanali, Antony M. Hooper, Zeyaur Khan, Festus Kaberia, John A. Pickett, Lester J. Wadhams Jan 2003

Isoflavanones From The Allelopathic Aqueous Root Exudate Of Desmodium Uncinatum, Muniru K. Tsanuo, Ahmed Hassanali, Antony M. Hooper, Zeyaur Khan, Festus Kaberia, John A. Pickett, Lester J. Wadhams

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Three isoflavanones, 5,7,2′,4′ -tetrahydroxy-6-(3-methylbut-2-enyl)isoflavanone (1), 4″,5″ -dihydro-5,2′,4′-trihydroxy-5″-isopropenylfurano-(2″, 3″;7,6)-isoflavanone (2) and 4″,5″-dihydro-2′ -methoxy-5,4′-dihydroxy-5″-isopropenylfurano-(2″,3″;7,6) -isoflavanone (3) and a previously known isoflavone 5,7,4′ -trihydroxyisoflavone [genistein (4)] were isolated and characterised spectroscopically from the root exudate of the legume Desmodium uncinatum (Jacq.) DC. We propose the names uncinanone A, B, and C for compounds 1, 2 and 3, respectively. Isolated fractions containing uncinanone B (2) induced germination of seeds from the parasitic weed Striga hermonthica (Del.) Benth. and fractions containing uncinanone C (3) moderately inhibited radical growth, the first example of a newly identified potential allelopathic mechanism to prevent S. hermonthica parasitism. © 2003 …

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Spatial And Temporal Heterogeneity Of Anopheles Mosquitoes And Plasmodium Falciparum Transmission Along The Kenyan Coast, Charles M. Mbogo, Joseph M. Mwangangi, Joseph G. Nzovu, Weidong Gu, Guiyan Yan, James T. Gunter, Chris Swalm, Joseph Keating, James L. Regens, Josephat I. Shililu, John I. Githure, John C. Beier Jan 2003

Spatial And Temporal Heterogeneity Of Anopheles Mosquitoes And Plasmodium Falciparum Transmission Along The Kenyan Coast, Charles M. Mbogo, Joseph M. Mwangangi, Joseph G. Nzovu, Weidong Gu, Guiyan Yan, James T. Gunter, Chris Swalm, Joseph Keating, James L. Regens, Josephat I. Shililu, John I. Githure, John C. Beier

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The seasonal dynamics and spatial distributions of Anopheles mosquitoes and Plasmodium falciparum parasites were studied for one year at 30 villages in Malindi, Kilifi, and Kwale Districts along the coast of Kenya. Anopheline mosquitoes were sampled inside houses at each site once every two months and malaria parasite prevalence in local school children was determined at the end of the entomologic survey. A total of 5,476 Anopheles gambiae s.l. and 3,461 An. funestus were collected. Species in the An. gambiae complex, identified by a polymerase chain reaction, included 81.9% An. gambiae s.s., 12.8% An. arabiensis, and 5.3% An. merus. Anopheles …

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