Open Access. Powered by Scholars. Published by Universities.®

Entomology Commons™

Open Access. Powered by Scholars. Published by Universities.®

All Peer-Reviewed Publications

Discipline
Keyword
Publication Year
File Type

Articles 751 - 780 of 1129

Full-Text Articles in Entomology

Wide-Scale Application Of Bti/Bs Biolarvicide In Different Aquatic Habitat Types In Urban And Peri-Urban Malindi, Kenya, Joseph M. Mwangangi, Samuel C. Kahindi, Lydiah W. Kibe, Joseph G. Nzovu, Peter Luethy, John I. Githure, Charles M. Mbogo Jun 2011

Wide-Scale Application Of Bti/Bs Biolarvicide In Different Aquatic Habitat Types In Urban And Peri-Urban Malindi, Kenya, Joseph M. Mwangangi, Samuel C. Kahindi, Lydiah W. Kibe, Joseph G. Nzovu, Peter Luethy, John I. Githure, Charles M. Mbogo

All Peer-Reviewed Publications

Larval control is a major component in mosquito control programs. This study evaluated the wide-scale application of Bti/Bs biolarvicide (Bacillus thuringiensis var. israelensis [Bti] and Bacillus sphaericus [Bs]) in different aquatic habitats in urban and peri-urban Malindi, Kenya. This study was done from June 2006 to December 2007. The urban and peri-urban area of Malindi town was mapped and categorized in grid cells of 1 km2. A total of 16 1-km2 cells were selected based on presence Community Based Organization dealing with malaria control within the cells. Each of the 16 1-km2 cells was thoroughly searched for the presence of …

Go to article

Study On Weight Loss And Moisture Regain Of Silk Cocoon Shells And Degummed Fibers From African Wild Silkmoths, Addis Teshome, S. K. Raina, F. Vollrath, J. M. Kabaru, J. Onyari, E. K. Nguku Jun 2011

Study On Weight Loss And Moisture Regain Of Silk Cocoon Shells And Degummed Fibers From African Wild Silkmoths, Addis Teshome, S. K. Raina, F. Vollrath, J. M. Kabaru, J. Onyari, E. K. Nguku

All Peer-Reviewed Publications

A study was conducted to determine weight loss and moisture regain properties of silk cocoon shells, shell layers and degummed fibers of the four African wild silkmoths Anaphe panda, Argema mimosae, Epiphora bauhiniae and Gonometa postica and compare with the industry standard mulberry silkmoth, Bombyx mori. No. significant difference was observed between the moisture regain of the wild silk fibers after degumming. However, there were significant differences in weight loss and moisture regain between cocoon shells as well as shell layers. E. bauhiniae had the lowest weight loss and moisture regain of 23.19 and 5.64%, respectively while G. postica had …

Go to article

Phylogenetics, Species Boundaries And Timing Of Resource Tracking In A Highly Specialized Group Of Seed Beetles (Coleoptera: Chrysomelidae: Bruchinae), Gael J. Kergoat, Bruno P. Le Ru, Gwenaelle Genson, Corinne Cruaud, Arnaud Couloux, Alex Delobel Jun 2011

Phylogenetics, Species Boundaries And Timing Of Resource Tracking In A Highly Specialized Group Of Seed Beetles (Coleoptera: Chrysomelidae: Bruchinae), Gael J. Kergoat, Bruno P. Le Ru, Gwenaelle Genson, Corinne Cruaud, Arnaud Couloux, Alex Delobel

All Peer-Reviewed Publications

Though for a long time it was hypothesized that the extraordinary diversity of phytophagous insects was better explained by a synchronous pattern of co-diversification with plants, the results of recent studies have led to question this theory, suggesting that the diversification of insects occurred well after that of their hosts. In this study we address this issue by investigating the timing of diversification of a highly specialized group of seed beetles, which mostly feeds on legume plants from the tribe Indigofereae. To that purpose, a total of 130 specimens were sequenced for six genes and analyzed under a Bayesian phylogenetic …

Go to article

Plasmodium Falciparum Transmission And Aridity: A Kenyan Experience From The Dry Lands Of Baringo And Its Implications For Anopheles Arabiensis Control, Albert O. Mala, Lucy W. Irungu, Josephat I. Shililu, Ephantus J. Muturi, Charles M. Mbogo, Joseph K. Njagi, Wolfgang R. Mukabana, John I. Githure May 2011

Plasmodium Falciparum Transmission And Aridity: A Kenyan Experience From The Dry Lands Of Baringo And Its Implications For Anopheles Arabiensis Control, Albert O. Mala, Lucy W. Irungu, Josephat I. Shililu, Ephantus J. Muturi, Charles M. Mbogo, Joseph K. Njagi, Wolfgang R. Mukabana, John I. Githure

All Peer-Reviewed Publications

Background: The ecology of malaria vectors particularly in semi-arid areas of Africa is poorly understood. Accurate knowledge on this subject will boost current efforts to reduce the burden of malaria in sub-Saharan Africa. The objective of this study was to describe the dynamics of malaria transmission in two model semi-arid sites (Kamarimar and Tirion) in Baringo in Kenya. Methods: Adult mosquitoes were collected indoors by pyrethrum spray collections (PSC) and outdoors by Centers for Disease Control (CDC) light traps and identified to species by morphological characteristics. Sibling species of Anopheles gambiae complex were further characterized by rDNA. PCR and enzyme-linked …

Go to article

A Longitudinal Study On Anopheles Mosquito Larval Abundance In Distinct Geographical And Environmental Settings In Western Kenya, Susan S. Imbahale, Krijn P. Paaijmans, Wolfgang R. Mukabana, Ron Van Lammeren, Andrew K. Githeko, Willem Takken Apr 2011

A Longitudinal Study On Anopheles Mosquito Larval Abundance In Distinct Geographical And Environmental Settings In Western Kenya, Susan S. Imbahale, Krijn P. Paaijmans, Wolfgang R. Mukabana, Ron Van Lammeren, Andrew K. Githeko, Willem Takken

All Peer-Reviewed Publications

Background: As the ecology of mosquito larvae can be complex there is need to develop a rational framework for undertaking larval ecological studies. Local environmental characteristics, such as altitude, climate and land use, can significantly impact on phenology and population dynamics of mosquito larvae, and indirectly affect the dynamics of mosquito-borne diseases. The aim of this study was to assess the feasibility of implementing an integrated approach to larval source management under the distinct ecological settings. Methods. The study was conducted in two highland villages and one village, at a lower altitude, in the Lake Victoria basin, where malaria is …

Go to article

Tracking The Feeding Patterns Of Tsetse Flies (Glossina Genus) By Analysis Of Bloodmeals Using Mitochondrial Cytochromes Genes, Catherine N. Muturi, Johnson O. Ouma, Imna I. Malele, Raphael M. Ngure, Jane J. Rutto, Klaus M. Mithöfer, John Enyaru, Daniel K. Masiga Mar 2011

Tracking The Feeding Patterns Of Tsetse Flies (Glossina Genus) By Analysis Of Bloodmeals Using Mitochondrial Cytochromes Genes, Catherine N. Muturi, Johnson O. Ouma, Imna I. Malele, Raphael M. Ngure, Jane J. Rutto, Klaus M. Mithöfer, John Enyaru, Daniel K. Masiga

All Peer-Reviewed Publications

Tsetse flies are notoriously difficult to observe in nature, particularly when populations densities are low. It is therefore difficult to observe them on their hosts in nature; hence their vertebrate species can very often only be determined indirectly by analysis of their gut contents. This knowledge is a critical component of the information on which control tactics can be developed. The objective of this study was to determine the sources of tsetse bloodmeals, hence investigate their feeding preferences. We used mitochondrial cytochrome c oxidase 1 (COI) and cytochrome b (cytb) gene sequences for identification of tsetse fly blood meals, in …

Go to article

Dry Season Ecology Of Anopheles Gambiae Complex Mosquitoes At Larval Habitats In Two Traditionally Semi-Arid Villages In Baringo, Kenya, Albert O. Mala, Lucy W. Irungu, Josephat I. Shililu, Ephantus J. Muturi, Charles C. Mbogo, Joseph K. Njagi, John I. Githure Mar 2011

Dry Season Ecology Of Anopheles Gambiae Complex Mosquitoes At Larval Habitats In Two Traditionally Semi-Arid Villages In Baringo, Kenya, Albert O. Mala, Lucy W. Irungu, Josephat I. Shililu, Ephantus J. Muturi, Charles C. Mbogo, Joseph K. Njagi, John I. Githure

All Peer-Reviewed Publications

Background: Pre-adult stages of malaria vectors in semi-arid areas are confronted with highly variable and challenging climatic conditions. The objective of this study was to determine which larval habitat types are most productive in terms of larval densities in the dry and wet seasons within semi-arid environments, and how vector species productivity is partitioned over time. Methods: Larval habitats were mapped and larvae sampled longitudinally using standard dipping techniques. Larvae were identified to species level morphologically using taxonomic keys and to sub-species by polymerase chain reaction (PCR) methods. Physical characteristics of larval habitats, including water depth, turbidity, and presence of …

Go to article

Improvement Of A Synthetic Lure For Anopheles Gambiae Using Compounds Produced By Human Skin Microbiota, Niels O. Verhulst, Phoebe A. Mbadi, Gabriella Bukovinszkiné Kiss, Wolfgang R. Mukabana, Joop J.A. Van Loon, Willem Takken, Renate C. Smallegange Feb 2011

Improvement Of A Synthetic Lure For Anopheles Gambiae Using Compounds Produced By Human Skin Microbiota, Niels O. Verhulst, Phoebe A. Mbadi, Gabriella Bukovinszkiné Kiss, Wolfgang R. Mukabana, Joop J.A. Van Loon, Willem Takken, Renate C. Smallegange

All Peer-Reviewed Publications

Background. Anopheles gambiae sensu stricto is considered to be highly anthropophilic and volatiles of human origin provide essential cues during its host-seeking behaviour. A synthetic blend of three human-derived volatiles, ammonia, lactic acid and tetradecanoic acid, attracts A. gambiae. In addition, volatiles produced by human skin bacteria are attractive to this mosquito species. The purpose of the current study was to test the effect of ten compounds present in the headspace of human bacteria on the host-seeking process of A. gambiae. The effect of each of the ten compounds on the attractiveness of a basic blend of ammonia, lactic and …

Go to article

Diversity Of Agromyzidae And Associated Hymenopteran Parasitoid Species In The Afrotropical Region: Implications For Biological Control, Robert Musundire, Adenirin Chabi-Olaye, Bernhard Löhr, Kerstin Krüger Feb 2011

Diversity Of Agromyzidae And Associated Hymenopteran Parasitoid Species In The Afrotropical Region: Implications For Biological Control, Robert Musundire, Adenirin Chabi-Olaye, Bernhard Löhr, Kerstin Krüger

All Peer-Reviewed Publications

Agromyzidae (Diptera) is a family with many species of economic importance on agricultural plants. However, many species are attacked by hymenopteran parasitoids which are known to be habitat rather than species specific. In the Afrotropical region, information about agromyzid and parasitoid diversity in different habitats is scattered in literature. Our aim was to assemble this dispersed information and discuss future needs of biological control efforts against invasive agromyzids in the Afrotropics. From published information, 581 agromyzid records comprising 302 species from 20 genera were recorded from 48 plant families. Parasitoids (90 records) were associated only with 20 agromyzid species belonging …

Go to article

Effect Of Infection By Metarhizium Anisopliae (Hypocreales: Clavicipitaceae) On The Feeding And Oviposition Of The Pea Leafminer Liriomyza Huidobrensis (Diptera: Agromyzidae) On Different Host Plants, L. N. Migiro, N. K. Maniania, A. Chabi-Olaye, A. Wanjoya, J. Vandenberg Feb 2011

Effect Of Infection By Metarhizium Anisopliae (Hypocreales: Clavicipitaceae) On The Feeding And Oviposition Of The Pea Leafminer Liriomyza Huidobrensis (Diptera: Agromyzidae) On Different Host Plants, L. N. Migiro, N. K. Maniania, A. Chabi-Olaye, A. Wanjoya, J. Vandenberg

All Peer-Reviewed Publications

The effect of fungal infection by Metarhizium anisopliae on feeding and oviposition of adult Liriomyza huidobrensis was examined on three host plants, faba bean (Vicia faba), French bean (Phaseolus vuklgaris) and snow pea (Pisum sativum) in the laboratory. Flies were contaminated with dry conidia and allowed to feed and oviposit on the different host plants. Mortality in L. huidobrensis varied between 14% and 20% in the controls and between 77% and 100% in fungal treatments 120h post-infection for the three host plants. L. huidobrensis made more punctures (47.3-52.6cm-2) in the control than in the fungal treatments (23.1-26.9cm-2) for the three …

Go to article

Detection Of Phytoplasma By Loop-Mediated Isothermal Amplification Of Dna (Lamp), E. Obura, D. Masiga, F. Wachira, B. Gurja, Z. R. Khan Feb 2011

Detection Of Phytoplasma By Loop-Mediated Isothermal Amplification Of Dna (Lamp), E. Obura, D. Masiga, F. Wachira, B. Gurja, Z. R. Khan

All Peer-Reviewed Publications

Napier stunt phytoplasma (16SrXI and 16SrIII) in eastern Africa is a serious threat to the expansion of Napier grass (Pennisetum purpureum) farming in the region, where it is widely cultivated as fodder in zero grazing livestock systems. The grass has high potential for bio-fuel production, and has been adopted by farmers as a countermeasure to cereal stem borer Lepidoptera, since it attracts and traps the insect. Diagnosis of stunt phytoplasma have been largely by nested polymerase chain reaction (nPCR) targeting the 16S rRNA gene. However, the method is laborious, costly and technically demanding. This investigation has developed a simpler but …

Go to article

Phylogeographic Structure Of Teretrius Nigrescens (Coleoptera: Histeridae) Predator Of The Invasive Post Harvest Pest Prostephanus Truncatus (Coleoptera: Bostrichidae)., B. A. Omondi, J. Van Den Berg, D. Masiga, F. Schulthess Jan 2011

Phylogeographic Structure Of Teretrius Nigrescens (Coleoptera: Histeridae) Predator Of The Invasive Post Harvest Pest Prostephanus Truncatus (Coleoptera: Bostrichidae)., B. A. Omondi, J. Van Den Berg, D. Masiga, F. Schulthess

All Peer-Reviewed Publications

The invasive larger grain borer Prostephanus truncatus (Horn) is the most important pest of farm-stored maize in Africa. It was introduced into the continent from Mesoamerica in the late 1970s and by 2008 had spread to at least 18 countries. Classical biological control using two populations of the predator Teretrius nigrescens Lewis achieved long-term and cost effective control in warm-humid areas, but not in cool and hot-dry zones. The present study investigated the phylogenetic relationships between geographical populations of the predator. Ten populations of T. nigrescens were studied using randomly amplified polymorphic DNA polymerase chain reaction (RAPD-PCR), sequence analysis of …

Go to article

Parasitism Of Lepidopterous Stem Borers In Cultivated And Natural Habitats, Duna Madu Mailafiya, Bruno Pierre Le Ru, Eunice Waitherero Kairu, Stéphane Dupas, Paul-André Calatayud Jan 2011

Parasitism Of Lepidopterous Stem Borers In Cultivated And Natural Habitats, Duna Madu Mailafiya, Bruno Pierre Le Ru, Eunice Waitherero Kairu, Stéphane Dupas, Paul-André Calatayud

All Peer-Reviewed Publications

Plant infestation, stem borer density, parasitism, and parasitoid abundance were assessed during two years in two host plants, Zea mays (L.) (Cyperales: Poaceae) and Sorghum bicolor (L.) (Cyperales: Poaceae), in cultivated habitats. The four major host plants (Cyperus spp., Panicum spp., Pennisetum spp., and Sorghum spp.) found in natural habitats were also assessed, and both the cultivated and natural habitat species occurred in four agroecological zones in Kenya. Across habitats, plant infestation (23.2%), stem borer density (2.2 per plant), and larval parasitism (15.0%) were highest in maize in cultivated habitats. Pupal parasitism was not higher than 4.7% in both habitats, …

Go to article

Dissemination Of Entomopathogenic Fungi Using Busseola Fusca Male As Vector, Nguya K. Maniania, Elizabeth Ouna, Peter Ahuya, Brigitte Frérot, Anne Emmanuelle Félix, Bruno Le Ru, Paul André Calatayud Jan 2011

Dissemination Of Entomopathogenic Fungi Using Busseola Fusca Male As Vector, Nguya K. Maniania, Elizabeth Ouna, Peter Ahuya, Brigitte Frérot, Anne Emmanuelle Félix, Bruno Le Ru, Paul André Calatayud

All Peer-Reviewed Publications

The stem borer, Busseola fusca (Fuller), is an important pest of maize Zea mays L. and sorghum Sorghum bicolor (L.) in eastern and southern Africa. To control this pest, biological control methods including the use of entomopathogenic fungi are being considered. The pathogenicity of one isolate of Metarhizium anisopliae (Metsch.) Sorok. and one isolate of Beauveria bassiana Bals. (Vuill.) were first tested on different developmental stages of B. fusca including eggs, neonate, 2nd and 3rd-instar larvae. Both fungal isolates were pathogenic to all the stages tested. However, differences in mortality were observed among larvae that hatched from treated egg masses. …

Go to article

Sex Pheromone Composition And Reproductive Isolation In Two Busseola Species (Lepidoptera: Noctuidae) In Kenya, A. E. Félix, P. A. Calatayud, B. Le Ru, J. F. Silvain, B. Frérot Jan 2011

Sex Pheromone Composition And Reproductive Isolation In Two Busseola Species (Lepidoptera: Noctuidae) In Kenya, A. E. Félix, P. A. Calatayud, B. Le Ru, J. F. Silvain, B. Frérot

All Peer-Reviewed Publications

Closely related species provide an interesting and useful model to understand mate communication diversification. Pre-mating isolation is the result of selection processes and is achieved by utilization of different sex pheromones, but also by different ecological and life traits such as geographic distribution, host-plant specialization and allochrony of sexual behavior. Here, we report sex pheromone identifications and pre-mating isolation of two closely related species of stemborers: Busseola segeta and the yet undescribed Busseola nov. sp., developing on different host-plants and in different geographical locations in Kenya. GC-MS analyses showed that the two species produced the same pheromone components, but in …

Go to article

Oviposition Preferences Of The African Wild Silkmoth, Gonometa Postica Walker (Lepidoptera: Lasiocampidae) On Different Substrates, Ken O. Fening, Esther N. Kioko, Jones M. Mueke, Suresh K. Raina Jan 2011

Oviposition Preferences Of The African Wild Silkmoth, Gonometa Postica Walker (Lepidoptera: Lasiocampidae) On Different Substrates, Ken O. Fening, Esther N. Kioko, Jones M. Mueke, Suresh K. Raina

All Peer-Reviewed Publications

Gonometa postica Walker (Lepidoptera: Lasiocampidae) is currently being utilised for commercial wild silk production in Eastern Kenya. The oviposition preferences of female G. postica on four substrates in a net-sleeved cage was studied in the laboratory in the long and short rainy seasons in 2007 for two generations, i. e. early (late March to April) and late flights (late September to October) of the moth. The first generation moths laid the highest number of eggs on net sleeves followed by plastic pot, twigs and wooden plank, whereas the second generation moths preferred wooden plank and net sleeves over the plastic …

Go to article

The Flight Activity Of Prostephanus Truncatus (Horn) (Coleoptera: Bostrichidae) And Teretrius Nigrescens Lewis (Coleoptera: Histeridae) In Kenya, Bonaventure Aman Omondi, Nanqing Jiang, Johnnie Van Den Berg, Fritz Schulthess Jan 2011

The Flight Activity Of Prostephanus Truncatus (Horn) (Coleoptera: Bostrichidae) And Teretrius Nigrescens Lewis (Coleoptera: Histeridae) In Kenya, Bonaventure Aman Omondi, Nanqing Jiang, Johnnie Van Den Berg, Fritz Schulthess

All Peer-Reviewed Publications

The invasive storage pest, the larger grain borer (LGB) Prostephanus truncatus (Horn), was introduced into the maize-deficit, semi-arid areas of the eastern region in Kenya in the early 1980s. In spite of containment efforts and the introduction of the predator Teretrius nigrescens Lewis from Mexico, LGB has spread to the main maize production zone in western Kenya during the past five years. The present work presents results from a 28-month monitoring effort of LGB and its predator, using pheromone traps at five locations along an east-west transect across Kenya. LGB occurred in all regions with highest trap catches in the …

Go to article

Repellent Activity Of Catmint, Nepeta Cataria, And Iridoid Nepetalactone Isomers Against Afro-Tropical Mosquitoes, Ixodid Ticks And Red Poultry Mites, Michael A. Birkett, Ahmed Hassanali, Solveig Hoglund, Jan Pettersson, John A. Pickett Jan 2011

Repellent Activity Of Catmint, Nepeta Cataria, And Iridoid Nepetalactone Isomers Against Afro-Tropical Mosquitoes, Ixodid Ticks And Red Poultry Mites, Michael A. Birkett, Ahmed Hassanali, Solveig Hoglund, Jan Pettersson, John A. Pickett

All Peer-Reviewed Publications

The repellent activity of the essential oil of the catmint plant, Nepeta cataria (Lamiaceae), and the main iridoid compounds (4aS,7S,7aR) and (4aS,7S,7aS)-nepetalactone, was assessed against (i) major Afro-tropical pathogen vector mosquitoes, i.e. The malaria mosquito, Anopheles gambiae s.s. and the Southern house mosquito, Culex quinquefasciatus, using a World Health Organisation (WHO)-approved topical application bioassay (ii) the brown ear tick, Rhipicephalus appendiculatus, using a climbing repellency assay, and (iii) the red poultry mite, Dermanyssus gallinae, using field trapping experiments. Gas chromatography (GC) and coupled GC-mass spectrometry (GC-MS) analysis of two N. cataria chemotypes (A and B) used in the repellency assays …

Go to article

Systematics And Molecular Phylogeny Of Two African Stem Borer Genera, Sciomesa Tams & Bowden And Carelis Bowden (Lepidoptera: Noctuidae), P. Moyal, B. Le Ru, D. Conlong, D. Cugala, B. Defabachew, T. Matama-Kauma, B. Pallangyo, J. Van Den Berg Dec 2010

Systematics And Molecular Phylogeny Of Two African Stem Borer Genera, Sciomesa Tams & Bowden And Carelis Bowden (Lepidoptera: Noctuidae), P. Moyal, B. Le Ru, D. Conlong, D. Cugala, B. Defabachew, T. Matama-Kauma, B. Pallangyo, J. Van Den Berg

All Peer-Reviewed Publications

Currently, the systematics of the African noctuid stem borers of the subtribe Sesamiina, which include major pests of cereals, is confused. In addition, their ecology is poorly known, as are the factors influencing their evolution. In this paper, we address these shortcomings for two genera of the Sesamiina, Sciomesa Tams & Bowden and Carelis Bowden. Mixed Bayesian phylogenetic analysis, which included their host plants and two mitochondrial genes, showed the genus Sciomesa to be polyphyletic. Two new genera were created, Pirateolea and Feraxinia. The genus Carelis proved to be paraphyletic and was subdivided into two sub-genera. The genera Sciomesa, Carelis …

Go to article

Control Of Cuticle Sclerotization In Two Species Of Tsetse Fly Larvae (Diptera: Glossinidae), David L. Whitehead Dec 2010

Control Of Cuticle Sclerotization In Two Species Of Tsetse Fly Larvae (Diptera: Glossinidae), David L. Whitehead

All Peer-Reviewed Publications

The presence of ecdysteroids during the larval life cycle and in the abdomens and ovaries of pregnant tsetse flies was established using radioimmunoassay. The hormone titre rises on day 9 of the larval life cycle 2-3 days after the hardening of the polypneustic lobes, mouthparts, phragma and anus. How initiation of tanning of the cuticle of the polypneustic lobes and later the puparium of tsetse fly is regulated is discussed as these events are separated in time by several days. It would seem to be unlikely that the pyrokinin neuropeptide, which is responsible for initiating the events that lead up …

Go to article

Genome-Wide Patterns Of Gene Expression During Aging In The African Malaria Vector Anopheles Gambiae, Mei Hui Wang, Osvaldo Marinotti, Anthony A. James, Edward Walker, John Githure, Guiyun Yan Oct 2010

Genome-Wide Patterns Of Gene Expression During Aging In The African Malaria Vector Anopheles Gambiae, Mei Hui Wang, Osvaldo Marinotti, Anthony A. James, Edward Walker, John Githure, Guiyun Yan

All Peer-Reviewed Publications

The primary means of reducing malaria transmission is through reduction in longevity in days of the adult female stage of the Anopheles vector. However, assessing chronological age is limited to crude physiologic methods which categorize the females binomially as either very young (nulliparous) or not very young (parous). Yet the epidemiologically relevant reduction in life span falls within the latter category. Age-grading methods that delineate chronological age, using accurate molecular surrogates based upon gene expression profiles, will allow quantification of the longevity-reducing effects of vector control tools aimed at the adult, female mosquito. In this study, microarray analyses of gene …

Go to article

Ovaries And Germline Cysts And Their Evolution In Dermaptera (Insecta), Wacław Tworzydło, Szczepan M. Biliński, Petr Kočárek, Fabian Haas Sep 2010

Ovaries And Germline Cysts And Their Evolution In Dermaptera (Insecta), Wacław Tworzydło, Szczepan M. Biliński, Petr Kočárek, Fabian Haas

All Peer-Reviewed Publications

We studied the ovary structure and initial stages of oogenesis in 15 representatives of several dermapteran taxa, including the epizoic Arixeniina. In all examined species, the ovaries are meroistic-polytrophic. The ovaries of the basal taxa ('Pygidicranidae', 'Diplatyidae', and Labiduridae) are composed of elongated ovarioles, attached to short lateral oviducts. In these groups, ovarioles contain several (more than 30) ovarian follicles in a linear arrangement. In the Eudermaptera, the ovaries are composed of 1-6 (Spongiphoridae) or 20-40 (Forficulidae, Chelisochidae) short ovarioles (containing 2 ovarian follicles only) that open to strongly elongated lateral oviducts. In all investigated dermapterans, the ovarian follicles are …

Go to article

Arm-In-Cage Testing Of Natural Human-Derived Mosquito Repellents, James G. Logan, Nina M. Stanczyk, Ahmed Hassanali, Joshua Kemei, Antônio E.G. Santana, Karlos A.L. Ribeiro, John A. Pickett, A. Jennifer Mordue Aug 2010

Arm-In-Cage Testing Of Natural Human-Derived Mosquito Repellents, James G. Logan, Nina M. Stanczyk, Ahmed Hassanali, Joshua Kemei, Antônio E.G. Santana, Karlos A.L. Ribeiro, John A. Pickett, A. Jennifer Mordue

All Peer-Reviewed Publications

Background. Individual human subjects are differentially attractive to mosquitoes and other biting insects. Previous investigations have demonstrated that this can be attributed partly to enhanced production of natural repellent chemicals by those individuals that attract few mosquitoes in the laboratory. The most important compounds in this respect include three aldehydes, octanal, nonanal and decanal, and two ketones, 6-methyl-5-hepten-2-one and geranylacetone [(E)-6,10-dimethylundeca-5,9-dien-2-one]. In olfactometer trials, these compounds interfered with attraction of mosquitoes to a host and consequently show promise as novel mosquito repellents. Methods. To test whether these chemicals could provide protection against mosquitoes, laboratory repellency trials were carried out to …

Go to article

Anopheles Larval Abundance And Diversity In Three Rice Agro-Village Complexes Mwea Irrigation Scheme, Central Kenya, Joseph M. Mwangangi, Josephat Shililu, Ephantus J. Muturi, Simon Muriu, Benjamin Jacob, Ephantus W. Kabiru, Charles M. Mbogo, John Githure, Robert J. Novak Aug 2010

Anopheles Larval Abundance And Diversity In Three Rice Agro-Village Complexes Mwea Irrigation Scheme, Central Kenya, Joseph M. Mwangangi, Josephat Shililu, Ephantus J. Muturi, Simon Muriu, Benjamin Jacob, Ephantus W. Kabiru, Charles M. Mbogo, John Githure, Robert J. Novak

All Peer-Reviewed Publications

Background. The diversity and abundance of Anopheles larvae has significant influence on the resulting adult mosquito population and hence the dynamics of malaria transmission. Studies were conducted to examine larval habitat dynamics and ecological factors affecting survivorship of aquatic stages of malaria vectors in three agro-ecological settings in Mwea, Kenya. Methods. Three villages were selected based on rice husbandry and water management practices. Aquatic habitats in the 3 villages representing planned rice cultivation (Mbui Njeru), unplanned rice cultivation (Kiamachiri) and non-irrigated (Murinduko) agro-ecosystems were sampled every 2 weeks to generate stage-specific estimates of mosquito larval densities, relative abundance and diversity. …

Go to article

Landmarks In The Evolution Of Technologies For Identifying Trypanosomes In Tsetse Flies, John C. Enyaru, Johnson O. Ouma, Imna I. Malele, Enock Matovu, Daniel K. Masiga Aug 2010

Landmarks In The Evolution Of Technologies For Identifying Trypanosomes In Tsetse Flies, John C. Enyaru, Johnson O. Ouma, Imna I. Malele, Enock Matovu, Daniel K. Masiga

All Peer-Reviewed Publications

Understanding what the trypanosome pathogens are, their vectors and mode of transmission underpin efforts to control the disease they cause in both humans and livestock. The risk of transmission is estimated by determining what proportion of the vector population is carrying the infectious pathogens. This risk also depends on the infectivity of the trypanosomes to humans and livestock. Most livestock pathogens are not infective to humans, whereas the two sub-species that infect humans also infect livestock. As with other infectious diseases, we can therefore trace the foundation of many continuing disease control programs for trypanosomiasis to the discovery of the …

Go to article

Geographic Distribution, Host Range And Perennation Of Cotesia Sesamiae And Cotesia Flavipes Cameron In Cultivated And Natural Habitats In Kenya, Duna Madu Mailafiya, Bruno Pierre Le Ru, Eunice Waitherero Kairu, Paul André Calatayud, Stéphane Dupas Jul 2010

Geographic Distribution, Host Range And Perennation Of Cotesia Sesamiae And Cotesia Flavipes Cameron In Cultivated And Natural Habitats In Kenya, Duna Madu Mailafiya, Bruno Pierre Le Ru, Eunice Waitherero Kairu, Paul André Calatayud, Stéphane Dupas

All Peer-Reviewed Publications

Field surveys were carried out in four agroecological zones to assess the geographic distribution, host range and perennation of Cotesia sesamiae and Cotesia flavipes in cultivated and natural habitats in Kenya. The distribution of the two Cotesia species in different ecological regions was most affected by the suitability of the local stem borer species for parasitoid development, and temperature, as both species were found in localities dominated by their suitable host(s) where temperature favoured their occurrence. Fourteen years after its release, C. flavipes has maintained a high level of specificity to its target host Chilo partellus on maize and sorghum …

Go to article

Novel Cross-Stage Solitarising Effect Of Gregarious-Phase Adult Desert Locust (Schistocerca Gregaria (Forskål)) Pheromone On Hoppers, Magzoub O. Bashir, Ahmed Hassanali Jun 2010

Novel Cross-Stage Solitarising Effect Of Gregarious-Phase Adult Desert Locust (Schistocerca Gregaria (Forskål)) Pheromone On Hoppers, Magzoub O. Bashir, Ahmed Hassanali

All Peer-Reviewed Publications

Previous studies had demonstrated stage differentiation in the cohesion (aggregation) pheromone systems of the desert locust, Schistocerca gregaria. In laboratory arena, the nymphal and adult stages responded aggregatively to their own pheromone, but dispersed evenly within the arena in the presence of the other. In the present study, we explored the effects of longer-term contact of field gregarious hopper bands and laboratory crowd-reared nymphs with the major constituent of the adult pheromone. During the first few days, hoppers in treated bands became relatively hyperactive. Over the next few days, their movements became random and they stopped marching as coherent groups, …

Go to article

Participatory Evaluation Of Integrated Pest And Soil Fertility Management Options Using Ordered Categorical Data Analysis, Hugo De Groote, Esther Rutto, George Odhiambo, Fred Kanampiu, Zeyaur Khan, Richard Coe, Bernard Vanlauwe Jun 2010

Participatory Evaluation Of Integrated Pest And Soil Fertility Management Options Using Ordered Categorical Data Analysis, Hugo De Groote, Esther Rutto, George Odhiambo, Fred Kanampiu, Zeyaur Khan, Richard Coe, Bernard Vanlauwe

All Peer-Reviewed Publications

Maize is becoming the major food crop around Lake Victoria. Major constraints to its production are Striga, stem borer, and declining soil fertility. Innovative integrated technologies have been developed: the 'push-pull' system (intercropping with Desmodium and surrounded by Napier grass), soybean and Crotalaria rotations, and imidazolinone-resistant (IR) maize seed. In 12 demonstration trials in four villages in Siaya and Vihiga districts (Kenya) and two villages in Busia (Uganda) in 2003 and 2004, 504 farmers evaluated all cropping systems and a mono-cropped continuous maize, each cropped with IR or local maize, and supplemented or not with fertilizer, totaling 16 treatments. Farmers …

Go to article

Population Structure Of Anopheles Gambiae Along The Kenyan Coast, Janet T. Midega, Ephantus J. Muturi, Frederick N. Baliraine, Charles M. Mbogo, John Githure, John C. Beier, Guiyun Yan May 2010

Population Structure Of Anopheles Gambiae Along The Kenyan Coast, Janet T. Midega, Ephantus J. Muturi, Frederick N. Baliraine, Charles M. Mbogo, John Githure, John C. Beier, Guiyun Yan

All Peer-Reviewed Publications

In the tropics, Anopheles mosquito abundance is greatest during the wet season and decline significantly during the dry season as larval habitats shrink. Population size fluctuations between wet and dry seasons may lead to variation in distribution of specific alleles within natural Anopheles populations, and a possible effect on the population genetic structure. We used 11 microsatellite markers to examine the effect of seasonality on population genetic structure of Anopheles gambiae s.s. at two sites along the Kenyan coast. All loci were highly polymorphic with the total number of alleles for pooled samples ranging from 7 (locus ND36) to 21 …

Go to article

Effect Of Seasons And Larval Food Plants On The Quality Of Gonometa Postica Cocoons, Ken O. Fening, Esther N. Kioko, Suresh K. Raina, Jones M. Mueke Apr 2010

Effect Of Seasons And Larval Food Plants On The Quality Of Gonometa Postica Cocoons, Ken O. Fening, Esther N. Kioko, Suresh K. Raina, Jones M. Mueke

All Peer-Reviewed Publications

The effect of food plants [Acacia elatior Brenan, A. tortilis (Forssk.) and A. nilotica (L.) Del.] on the development time of Gonometa postica Walker (Lepidoptera: Lasiocampidae) larvae and the quality of their cocoons was studied in the Imba and Mumoni forests of Mwingi, Eastern Kenya, during the long (March-May) and short (October-December) rainy seasons of 2006 and 2007. Larvae were reared in semi-captivity in net sleeves attached to branches of the plants. The period between hatching of eggs and spinning of cocoons, as well as their weight, as determinants of cocoon quality were recorded. In addition, collections of cocoons from …

Go to article

First Prev Next Last