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 691 - 720 of 1129

Full-Text Articles in Entomology

Comparative Diagnostic And Analytical Performance Of Pcr And Lamp-Based Trypanosome Detection Methods Estimated Using Pooled Whole Tsetse Flies And Midguts, Imna I. Malele, Johnson O. Ouma, John C.K. Enyaru, Enock Matovu, Vincent Alibu, Joanna E. Auma, Samuel G. Onyoyo, Rosemary Bateta, Robert E. Changasi, Phoebe W. Mukiria, Kariuki Ndung'u, Purity K. Gitonga, Lilian M. Mwaniki, Hamisi S. Nyingilili, Eugene A. Lyaruu, Lupakisyo A. Kapange, Peter Kuria Kamau, Daniel K. Masiga Oct 2013

Comparative Diagnostic And Analytical Performance Of Pcr And Lamp-Based Trypanosome Detection Methods Estimated Using Pooled Whole Tsetse Flies And Midguts, Imna I. Malele, Johnson O. Ouma, John C.K. Enyaru, Enock Matovu, Vincent Alibu, Joanna E. Auma, Samuel G. Onyoyo, Rosemary Bateta, Robert E. Changasi, Phoebe W. Mukiria, Kariuki Ndung'u, Purity K. Gitonga, Lilian M. Mwaniki, Hamisi S. Nyingilili, Eugene A. Lyaruu, Lupakisyo A. Kapange, Peter Kuria Kamau, Daniel K. Masiga

All Peer-Reviewed Publications

Detection of trypanosomes that cause disease in human beings and livestock within their tsetse fly hosts is an essential component of vector and disease control programmes. Several molecular-based diagnostic tests have been developed for this purpose. Many of these tests, while sensitive, require analysis of trypanosome DNA extracted from single flies, or from pooled tsetse fly heads and amplified trypanosome DNA. In this study, we evaluated the relative analytical and diagnostic sensitivities of two PCR-based tests (ITS and TBR) and a Trypanozoon specific LAMP assay using pooled whole tsetse flies and midguts spiked with serially diluted procyclics of a laboratory …

Go to article

Differential Attractiveness Of Human Foot Odours To Anopheles Gambiae Giles Sensu Stricto (Diptera: Culicidae) And Variation In Their Chemical Composition, M. O. Omolo, B. Njiru, I. O. Ndiege, R. M. Musau, A. Hassanali Oct 2013

Differential Attractiveness Of Human Foot Odours To Anopheles Gambiae Giles Sensu Stricto (Diptera: Culicidae) And Variation In Their Chemical Composition, M. O. Omolo, B. Njiru, I. O. Ndiege, R. M. Musau, A. Hassanali

All Peer-Reviewed Publications

Counter flow geometry (CFG) traps (American Biophysics) baited with foot odours (adsorbed overnight on a combination of a nylon and a cotton socks) from 4 groups of 4 male volunteers were initially used in a screen-house to compare and grade the attractiveness of Anopheles gambiae Giles sensu stricto to these odours. Ten individuals were then selected from the 4 groups for further grading in which mosquito attractiveness to odours adsorbed on socks worn by each of the individuals was compared against a control (clean, un-worn cotton and nylon socks). A gradation of attractiveness was found, with the most attractive foot …

Go to article

Coffee Berry Borer Joins Bark Beetles In Coffee Klatch, Juliana Jaramillo, Baldwyn Torto, Dickson Mwenda, Armin Troeger, Christian Borgemeister, Hans Michael Poehling, Wittko Francke Sep 2013

Coffee Berry Borer Joins Bark Beetles In Coffee Klatch, Juliana Jaramillo, Baldwyn Torto, Dickson Mwenda, Armin Troeger, Christian Borgemeister, Hans Michael Poehling, Wittko Francke

All Peer-Reviewed Publications

Unanswered key questions in bark beetle-plant interactions concern host finding in species attacking angiosperms in tropical zones and whether management strategies based on chemical signaling used for their conifer-attacking temperate relatives may also be applied in the tropics. We hypothesized that there should be a common link in chemical signaling mediating host location by these Scolytids. Using laboratory behavioral assays and chemical analysis we demonstrate that the yellow-orange exocarp stage of coffee berries, which attracts the coffee berry borer, releases relatively high amounts of volatiles including conophthorin, chalcogran, frontalin and sulcatone that are typically associated with Scolytinae chemical ecology. The …

Go to article

Seasonal Abundance Of Western Flower Thrips And Its Natural Enemies In Different French Bean Agroecosystems In Kenya, J. O. Nyasani, R. Meyhöfer, S. Subramanian, H. M. Poehling Sep 2013

Seasonal Abundance Of Western Flower Thrips And Its Natural Enemies In Different French Bean Agroecosystems In Kenya, J. O. Nyasani, R. Meyhöfer, S. Subramanian, H. M. Poehling

All Peer-Reviewed Publications

The seasonal abundance of western flower thrips (WFT) [Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)] and its natural enemies on French beans in two agro-ecological zones (AEZs) (high and mid altitude) in Kenya, was studied in three growing cycles from January to December 2009. French beans were sampled every 2 weeks for WFT and natural enemies. Results show that colonization of French beans with WFT in both farm scales studied in the two AEZs started at 2- to 3-leaf stage. There was an increase in the population density of WFT from budding stage to podding/flowering stage, and it declined at crop senescence. …

Go to article

Effect Of Leaf Type And Pesticide Exposure On Abundance Of Bacterial Taxa In Mosquito Larval Habitats, Ephantus J. Muturi, Benedict O. Orindi, Chang Hyun Kim Aug 2013

Effect Of Leaf Type And Pesticide Exposure On Abundance Of Bacterial Taxa In Mosquito Larval Habitats, Ephantus J. Muturi, Benedict O. Orindi, Chang Hyun Kim

All Peer-Reviewed Publications

Lentic freshwater systems including those inhabited by aquatic stages of mosquitoes derive most of their carbon inputs from terrestrial organic matter mainly leaf litter. The leaf litter is colonized by microbial communities that provide the resource base for mosquito larvae. While the microbial biomass associated with different leaf species in container aquatic habitats is well documented, the taxonomic composition of these microbes and their response to common environmental stressors is poorly understood. We used indoor aquatic microcosms to determine the abundances of major taxonomic groups of bacteria in leaf litters from seven plant species and their responses to low concentrations …

Go to article

Endophytic Colonization Of Vicia Faba And Phaseolus Vulgaris (Fabaceae) By Fungal Pathogens And Their Effects On The Life-History Parameters Of Liriomyza Huidobrensis (Diptera: Agromyzidae), K. S. Akutse, N. K. Maniania, K. K.M. Fiaboe, J. Van Den Berg, S. Ekesi Aug 2013

Endophytic Colonization Of Vicia Faba And Phaseolus Vulgaris (Fabaceae) By Fungal Pathogens And Their Effects On The Life-History Parameters Of Liriomyza Huidobrensis (Diptera: Agromyzidae), K. S. Akutse, N. K. Maniania, K. K.M. Fiaboe, J. Van Den Berg, S. Ekesi

All Peer-Reviewed Publications

Ten fungal isolates belonging to the genera Beauveria (3), Hypocrea (1), Gibberella (1), Metarhizium (2), Trichoderma (1) and Fusarium (2) were evaluated in the laboratory to determine whether they could become endophytic in two pea leafminer (Liriomyza huidobrensis) host plants (Vicia faba and Phaseolus vulgaris), and to assess their possible negative effects on leafminers. Beauveria (ICIPE279), Hypocrea, Gibberella, Fusarium and Trichoderma isolates colonized roots, stems and leaves of both host plant species. Beauveria isolates G1LU3 and S4SU1 colonized roots, stems, and leaves of P. vulgaris but only the root and stem of V. faba. Isolates of Metarhizium failed to colonize …

Go to article

Gene Expression-Based Biomarkers For Anopheles Gambiae Age Grading, Mei Hui Wang, Osvaldo Marinotti, Daibin Zhong, Anthony A. James, Edward Walker, Tom Guda, Eliningaya J. Kweka, John Githure, Guiyun Yan Jul 2013

Gene Expression-Based Biomarkers For Anopheles Gambiae Age Grading, Mei Hui Wang, Osvaldo Marinotti, Daibin Zhong, Anthony A. James, Edward Walker, Tom Guda, Eliningaya J. Kweka, John Githure, Guiyun Yan

All Peer-Reviewed Publications

Information on population age structure of mosquitoes under natural conditions is fundamental to the understanding of vectorial capacity and crucial for assessing the impact of vector control measures on malaria transmission. Transcriptional profiling has been proposed as a method for predicting mosquito age for Aedes and Anopheles mosquitoes, however, whether this new method is adequate for natural conditions is unknown. This study tests the applicability of transcriptional profiling for age-grading of Anopheles gambiae, the most important malaria vector in Africa. The transcript abundance of two An. gambiae genes, AGAP009551 and AGAP011615, was measured during aging under laboratory and field conditions …

Go to article

Dominant Inheritance Of Field-Evolved Resistance To Bt Corn In Busseola Fusca, Pascal Campagne, Marlene Kruger, Rémy Pasquet, Bruno Le Ru, Johnnie Van Den Berg Jul 2013

Dominant Inheritance Of Field-Evolved Resistance To Bt Corn In Busseola Fusca, Pascal Campagne, Marlene Kruger, Rémy Pasquet, Bruno Le Ru, Johnnie Van Den Berg

All Peer-Reviewed Publications

Transgenic crops expressing Bacillus thuringiensis (Bt) toxins have been adopted worldwide, notably in developing countries. In spite of their success in controlling target pests while allowing a substantial reduction of insecticide use, the sustainable control of these pest populations is threatened by the evolution of resistance. The implementation of the "high dose/refuge" strategy for managing insect resistance in transgenic crops aims at delaying the evolution of resistance to Bt crops in pest populations by promoting survival of susceptible insects. However, a crucial condition for the "high dose/refuge" strategy to be efficient is that the inheritance of resistance should be functionally …

Go to article

Candidate Chemosensory Genes In The Stemborer Sesamia Nonagrioides, Nicolas Glaser, Aurore Gallot, Fabrice Legeai, Nicolas Montagné, Erwan Poivet, Myriam Harry, Paul André Calatayud, Emmanuelle Jacquin-Joly Jun 2013

Candidate Chemosensory Genes In The Stemborer Sesamia Nonagrioides, Nicolas Glaser, Aurore Gallot, Fabrice Legeai, Nicolas Montagné, Erwan Poivet, Myriam Harry, Paul André Calatayud, Emmanuelle Jacquin-Joly

All Peer-Reviewed Publications

The stemborer Sesamia nonagrioides is an important pest of maize in the Mediterranean Basin. Like other moths, this noctuid uses its chemosensory system to efficiently interact with its environment. However, very little is known on the molecular mechanisms that underlie chemosensation in this species. Here, we used next-generation sequencing (454 and Illumina) on different tissues from adult and larvae, including chemosensory organs and female ovipositors, to describe the chemosensory transcriptome of S. nonagrioides and identify key molecular components of the pheromone production and detection systems. We identified a total of 68 candidate chemosensory genes in this species, including 31 candidate …

Go to article

Horizontal Transmission Of Metarhizium Anisopliae In Fruit Flies And Effect Of Fungal Infection On Egg Laying And Fertility, Susan Dimbi, Nguya K. Maniania, Sunday Ekesi Jun 2013

Horizontal Transmission Of Metarhizium Anisopliae In Fruit Flies And Effect Of Fungal Infection On Egg Laying And Fertility, Susan Dimbi, Nguya K. Maniania, Sunday Ekesi

All Peer-Reviewed Publications

Fly-to-fly transmission of conidia of the entomopathogenic fungus Metarhizium anisopliae and the effect of fungal infection on the reproductive potential of females surviving infection were investigated in three fruit fly species, Ceratitis cosyra, C. fasciventris, and C. capitata. The number of conidia picked up by a single fruit fly was determined in C. cosyra. The initial uptake (Day 0) of conidia by a single fly was approx. 1.1 × 106 conidia after exposure to the treated substrate. However, the number of conidia dropped from 7.2 × 105 to 4.1 × 105 conidia after 2 and 8 h post-exposure, respectively. The …

Go to article

Composition Of Stem Borer Communities In Selected Vegetation Mosaics In Kenya, G. O. Ong'amo, B. P. Le Ru, P. A. Calatayud, J. F. Silvain Jun 2013

Composition Of Stem Borer Communities In Selected Vegetation Mosaics In Kenya, G. O. Ong'amo, B. P. Le Ru, P. A. Calatayud, J. F. Silvain

All Peer-Reviewed Publications

Busseola fusca (Fuller), Sesamia calamistis Hampson, Chilo partellus (Swinhoe) and Chilo orichalcociliellus (Strand) are important stem borer pests of maize and sorghum in East Africa. Persistence of these pests in crop fields is blamed on the influx of diaspore populations from the neighbouring natural habitats. In addition to pest species, natural habitats support numerous non-economic stem borer species, some not known to science. However, due to growing human populations and accompanying global change, some of the natural habitats are undergoing rapid changes, a process that may result in the evolution of "new" pest species. In this study, we investigated stem …

Go to article

Transfer Of Inoculum Of Metarhizium Anisopliae Between Adult Glossina Morsitans Morsitans And Effects Of Fungal Infection On Blood Feeding And Mating Behaviors, Nguya K. Maniania, Matilda A. Okech, James O. Adino, Jacob O. Opere, Sunday Ekesi Jun 2013

Transfer Of Inoculum Of Metarhizium Anisopliae Between Adult Glossina Morsitans Morsitans And Effects Of Fungal Infection On Blood Feeding And Mating Behaviors, Nguya K. Maniania, Matilda A. Okech, James O. Adino, Jacob O. Opere, Sunday Ekesi

All Peer-Reviewed Publications

The transfer of conidia of Metarhizium anisopliae between tsetse flies Glossina morsitans and the effects of fungal inoculation on mating and blood meal feeding behaviors were investigated in the laboratory. Male or female flies were inoculated with fungal conidia ("donors") and allowed to pair with fungus-free mate of opposite sex ("recipients") at 1-day-interval up to three mates. Fungus-treated male or female "donor" flies as well as their mates "recipients" died from fungal infection. However, mortality in male "recipient" flies declined with successive mating, from 82.5 to 32.5 %. Fungus-treated males readily located female flies and mating was successful in most …

Go to article

Adaptive Selection On Bracovirus Genomes Drives The Specialization Of Cotesia Parasitoid Wasps, Séverine Jancek, Annie Bézier, Philippe Gayral, Corentin Paillusson, Laure Kaiser, Stéphane Dupas, Bruno Pierre Le Ru, Valérie Barbe, Georges Periquet, Jean Michel Drezen, Elisabeth A. Herniou May 2013

Adaptive Selection On Bracovirus Genomes Drives The Specialization Of Cotesia Parasitoid Wasps, Séverine Jancek, Annie Bézier, Philippe Gayral, Corentin Paillusson, Laure Kaiser, Stéphane Dupas, Bruno Pierre Le Ru, Valérie Barbe, Georges Periquet, Jean Michel Drezen, Elisabeth A. Herniou

All Peer-Reviewed Publications

The geographic mosaic of coevolution predicts parasite virulence should be locally adapted to the host community. Cotesia parasitoid wasps adapt to local lepidopteran species possibly through their symbiotic bracovirus. The virus, essential for the parasitism success, is at the heart of the complex coevolutionary relationship linking the wasps and their hosts. The large segmented genome contained in the virus particles encodes virulence genes involved in host immune and developmental suppression. Coevolutionary arms race should result in the positive selection of particular beneficial alleles. To understand the global role of bracoviruses in the local adaptation or specialization of parasitoid wasps to …

Go to article

Mosquito-Borne Arbovirus Surveillance At Selected Sites In Diverse Ecological Zones Of Kenya; 2007 - 2012, Caroline Ochieng, Joel Lutomiah, Albina Makio, Hellen Koka, Edith Chepkorir, Santos Yalwala, James Mutisya, Lillian Musila, Samoel Khamadi, Jason Richardson, Joshua Bast, David Schnabel, Eyako Wurapa, Rosemary Sang May 2013

Mosquito-Borne Arbovirus Surveillance At Selected Sites In Diverse Ecological Zones Of Kenya; 2007 - 2012, Caroline Ochieng, Joel Lutomiah, Albina Makio, Hellen Koka, Edith Chepkorir, Santos Yalwala, James Mutisya, Lillian Musila, Samoel Khamadi, Jason Richardson, Joshua Bast, David Schnabel, Eyako Wurapa, Rosemary Sang

All Peer-Reviewed Publications

Abstract. Background: Increased frequency of arbovirus outbreaks in East Africa necessitated the determination of distribution of risk by entomologic arbovirus surveillance. A systematic vector surveillance programme spanning 5 years and covering 11 sites representing seven of the eight provinces in Kenya and located in diverse ecological zones was carried out. Methods. Mosquitoes were sampled bi-annually during the wet seasons and screened for arboviruses. Mosquitoes were identified to species, pooled by species, collection date and site and screened for arboviruses by isolation in cell culture and/or RT-PCR screening and sequencing. Results: Over 450,000 mosquitoes in 15,890 pools were screened with 83 …

Go to article

Parasitological Prevalence Of Bovine Trypanosomosis In Kubo Division Of Kwale County Of Coastal: Baseline Survey, N. Mbahin, H. Affognon, J. Andoke, M. Tiberius, D. Mbuvi, J. Otieno, P. Muasa, R. K. Saini Apr 2013

Parasitological Prevalence Of Bovine Trypanosomosis In Kubo Division Of Kwale County Of Coastal: Baseline Survey, N. Mbahin, H. Affognon, J. Andoke, M. Tiberius, D. Mbuvi, J. Otieno, P. Muasa, R. K. Saini

All Peer-Reviewed Publications

Prior to field trials of large scale tsetse repellent technology validation in July 2011, a cross-sectional survey of bovine trypanosomosis and its vectors was carried out to know the disease level in Kwale County of Coastal Kenya. A total of 584 adult cattle were examined at ten different Locations. The trypanosome prevalence in cattle with regard to age, sex, location and apparent tsetse density was investigated. The overall trypanosome prevalence in cattle in Kubo Division of Kwale County was 33.9%. Two types of infections were recorded in various parts of the Division in the following proportions: T. congolense 61.1%, T. …

Go to article

Sex-Specific Induction Of Cyp6 Cytochrome P450 Genes In Cadmium And Lead Tolerant Anopheles Gambiae, Fauzia K. Musasia, Alfred O. Isaac, Daniel K. Masiga, Irene A. Omedo, Ramadhan Mwakubambanya, Richard Ochieng, Paul O. Mireji Mar 2013

Sex-Specific Induction Of Cyp6 Cytochrome P450 Genes In Cadmium And Lead Tolerant Anopheles Gambiae, Fauzia K. Musasia, Alfred O. Isaac, Daniel K. Masiga, Irene A. Omedo, Ramadhan Mwakubambanya, Richard Ochieng, Paul O. Mireji

All Peer-Reviewed Publications

Background: Anopheles gambiae, one of the main Afro-tropical mosquito vector of malaria, has adapted to heavy metals in its natural habitat, and developed resistance to most conventional insecticides. Investigations were conducted to establish an association between tolerance to cadmium or lead-heavy metals, and expression of specific genes for cytochrome p450 enzymes associated with pyrethroid resistance in the mosquito. Methods. Juvenile aquatic stages of the mosquito were selected for tolerance to cadmiun or lead through chronic exposure of the stages to maximum acceptable toxicant concentrations (MATCs) of the metals. Using real-time quantitative polymerase chain reaction (qPCR), three replicates each of male …

Go to article

The Functioning Of Species-Specific Olfactory Pheromones In The Biology Of A Mosquito-Eating Jumping Spider From East Africa, Fiona R. Cross, Robert R. Jackson Mar 2013

The Functioning Of Species-Specific Olfactory Pheromones In The Biology Of A Mosquito-Eating Jumping Spider From East Africa, Fiona R. Cross, Robert R. Jackson

All Peer-Reviewed Publications

Having unique, complex eyes and vision based on exceptional spatial acuity, salticid spiders are known for their vision-based predatory and mating strategies. Yet Evarcha culicivora, the salticid we consider here, is known for predatory and mating strategies based strongly on the interplay of vision and olfaction. This unusual East African species feeds indirectly on vertebrate blood by choosing blood-carrying female mosquitoes as preferred prey, which it can identify by sight and by smell. Moreover, E. culicivora's mating strategy is unusual because, unlike the prevailing general pattern among spiders, where males are more active in courtship and females are more active …

Go to article

Improving Sterile Insect Technique (Sit) For Tsetse Flies Through Research On Their Symbionts And Pathogens, Adly M.M. Abd-Alla, Max Bergoin, Andrew G. Parker, Nguya K. Maniania, Just M. Vlak, Kostas Bourtzis, Drion G. Boucias, Serap Aksoy Mar 2013

Improving Sterile Insect Technique (Sit) For Tsetse Flies Through Research On Their Symbionts And Pathogens, Adly M.M. Abd-Alla, Max Bergoin, Andrew G. Parker, Nguya K. Maniania, Just M. Vlak, Kostas Bourtzis, Drion G. Boucias, Serap Aksoy

All Peer-Reviewed Publications

Tsetse flies (Diptera: Glossinidae) are the cyclical vectors of the trypanosomes, which cause human African trypanosomosis (HAT) or sleeping sickness in humans and African animal trypanosomosis (AAT) or nagana in animals. Due to the lack of effective vaccines and inexpensive drugs for HAT, and the development of resistance of the trypanosomes against the available trypanocidal drugs, vector control remains the most efficient strategy for sustainable management of these diseases. Among the control methods used for tsetse flies, Sterile Insect Technique (SIT), in the frame of area-wide integrated pest management (AW-IPM), represents an effective tactic to suppress and/or eradicate tsetse flies. …

Go to article

Repellent, Irritant And Toxic Effects Of 20 Plant Extracts On Adults Of The Malaria Vector Anopheles Gambiae Mosquito, Emilie Deletre, Thibaud Martin, Pascal Campagne, Denis Bourguet, Andy Cadin, Chantal Menut, Romain Bonafos, Fabrice Chandre Feb 2013

Repellent, Irritant And Toxic Effects Of 20 Plant Extracts On Adults Of The Malaria Vector Anopheles Gambiae Mosquito, Emilie Deletre, Thibaud Martin, Pascal Campagne, Denis Bourguet, Andy Cadin, Chantal Menut, Romain Bonafos, Fabrice Chandre

All Peer-Reviewed Publications

Pyrethroid insecticides induce an excito-repellent effect that reduces contact between humans and mosquitoes. Insecticide use is expected to lower the risk of pathogen transmission, particularly when impregnated on long-lasting treated bednets. When applied at low doses, pyrethroids have a toxic effect, however the development of pyrethroid resistance in several mosquito species may jeopardize these beneficial effects. The need to find additional compounds, either to kill disease-carrying mosquitoes or to prevent mosquito contact with humans, therefore arises. In laboratory conditions, the effects (i.e., repellent, irritant and toxic) of 20 plant extracts, mainly essential oils, were assessed on adults of Anopheles gambiae, …

Go to article

Diversity Of Stem Borer Parasitoids And Their Associated Wild Host Plants In South Africa And Mozambique, H. J. Moolman, J. Van Den Berg, D. Conlong, D. Cugala, S. J. Siebert, B. P. Le Ru Feb 2013

Diversity Of Stem Borer Parasitoids And Their Associated Wild Host Plants In South Africa And Mozambique, H. J. Moolman, J. Van Den Berg, D. Conlong, D. Cugala, S. J. Siebert, B. P. Le Ru

All Peer-Reviewed Publications

The diversity of lepidopterous stem borers, their parasitoids and their associated wild host plants was studied in South Africa between 2006 and 2009 and in Mozambique between 2005 and 2010. In South Africa, 20 species of parasitoids were recovered from 17 stem borer species collected on 16 wild host plant species. From Mozambique, 14 parasitoid species were recorded from 16 stem borer species collected on 14 wild host plant species. The highest diversity of parasitoids was recorded on stem borers that attacked the host plants Phragmites australis (7 spp.) and Panicum maximum (6 spp.), in South Africa and Mozambique, respectively. …

Go to article

Two Sugar Isomers Influence Host Plant Acceptance By A Cereal Caterpillar Pest, G. Juma, M. Thiongo, L. Dutaur, K. Rharrabe, F. Marion-Poll, B. Le Ru, G. Magoma, J. F. Silvain, P. A. Calatayud Feb 2013

Two Sugar Isomers Influence Host Plant Acceptance By A Cereal Caterpillar Pest, G. Juma, M. Thiongo, L. Dutaur, K. Rharrabe, F. Marion-Poll, B. Le Ru, G. Magoma, J. F. Silvain, P. A. Calatayud

All Peer-Reviewed Publications

Abstract Plant sugars are often considered as primary feeding stimuli, conditioning host plant acceptance by herbivorous insects. Of the nine sugars identified from methanolic extracts of seven grass species, only turanose, a sucrose isomer, was negatively correlated with the survival and growth of the noctuid larva of cereal stemborer, Busseola fusca. Sucrose was the most abundant sugar, although it did not vary significantly in concentration among the plant species studied. Using Styrofoam™ cylinders impregnated with increasing concentrations of turanose or sucrose, the two sugars had opposing effects: turanose appeared phagodeterrent while sucrose was phagostimulatory. Electrophysiological studies indicated that B. fusca …

Go to article

Climate Change Or Urbanization? Impacts On A Traditional Coffee Production System In East Africa Over The Last 80 Years, Juliana Jaramillo, Mamoudou Setamou, Eric Muchugu, Adenirin Chabi-Olaye, Alvaro Jaramillo, Joseph Mukabana, Johnson Maina, Simon Gathara, Christian Borgemeister Jan 2013

Climate Change Or Urbanization? Impacts On A Traditional Coffee Production System In East Africa Over The Last 80 Years, Juliana Jaramillo, Mamoudou Setamou, Eric Muchugu, Adenirin Chabi-Olaye, Alvaro Jaramillo, Joseph Mukabana, Johnson Maina, Simon Gathara, Christian Borgemeister

All Peer-Reviewed Publications

Global environmental changes (GEC) such as climate change (CC) and climate variability have serious impacts in the tropics, particularly in Africa. These are compounded by changes in land use/land cover, which in turn are driven mainly by economic and population growth, and urbanization. These factors create a feedback loop, which affects ecosystems and particularly ecosystem services, for example plant-insect interactions, and by consequence agricultural productivity. We studied effects of GEC at a local level, using a traditional coffee production area in greater Nairobi, Kenya. We chose coffee, the most valuable agricultural commodity worldwide, as it generates income for 100 million …

Go to article

Comparison Of Volatile Blends And Nucleotide Sequences Of Two Beauveria Bassiana Isolates Of Different Virulence And Repellency Towards The Termite Macrotermes Michealseni, D. M. Mburu, N. K. Maniania, A. Hassanali Jan 2013

Comparison Of Volatile Blends And Nucleotide Sequences Of Two Beauveria Bassiana Isolates Of Different Virulence And Repellency Towards The Termite Macrotermes Michealseni, D. M. Mburu, N. K. Maniania, A. Hassanali

All Peer-Reviewed Publications

Isolates of the fungus Beauveria bassiana have different levels of virulence and repellency against the termite Macrotermes michaelseni. In the present study, we compared the volatile profiles and gene sequences of two isolates of the fungus with different levels of virulence and repellence to the termite. Gas chromatography-mass spectrometric analyses showed quantitative and qualitative differences in the composition of volatiles of the two isolates. The repellencies of synthetic blends of 10 prominent components that mimicked the volatiles of each of the two isolates were significantly different. Subtractive bioassays showed that the repellency of each isolate was due to synergistic effects …

Go to article

Development Of A Gravid Trap For Collecting Live Malaria Vectors Anopheles Gambiae S.L, Sisay Dugassa, Jenny M. Lindh, Florence Oyieke, Wolfgang R. Mukabana, Steven W. Lindsay, Ulrike Fillinger Jan 2013

Development Of A Gravid Trap For Collecting Live Malaria Vectors Anopheles Gambiae S.L, Sisay Dugassa, Jenny M. Lindh, Florence Oyieke, Wolfgang R. Mukabana, Steven W. Lindsay, Ulrike Fillinger

All Peer-Reviewed Publications

BACKGROUND: Effective malaria vector control targeting indoor host-seeking mosquitoes has resulted in fewer vectors entering houses in many areas of sub-Saharan Africa, with the proportion of vectors outdoors becoming more important in the transmission of this disease. This study aimed to develop a gravid trap for the outdoor collection of the malaria vector Anopheles gambiae s.l. based on evaluation and modification of commercially available gravid traps. METHODS: Experiments were implemented in an 80 m(2) semi-field system where 200 gravid Anopheles gambiae s.s. were released nightly. The efficacy of the Box, CDC and Frommer updraft gravid traps was compared. The Box …

Go to article

Comparison Of The Effects Of Extracts From Three Vitex Plant Species On Anopheles Gambiae S.S. (Diptera: Culicidae) Larvae, Mokua G. Nyamoita, Innocent Ester, Mbwambo H. Zakaria, Lwande Wilber, Ochola J. Bwire, Hassanali Ahmed Jan 2013

Comparison Of The Effects Of Extracts From Three Vitex Plant Species On Anopheles Gambiae S.S. (Diptera: Culicidae) Larvae, Mokua G. Nyamoita, Innocent Ester, Mbwambo H. Zakaria, Lwande Wilber, Ochola J. Bwire, Hassanali Ahmed

All Peer-Reviewed Publications

Acetone and methanol extracts of different parts of three Vitex species (leaves and stem bark of Vitex trifolia, leaves, stem bark and root bark of Vitex schiliebenii and stem and root bark of Vitex payos) were evaluated for their potential to control Anopheles gambiae Giles s.s. larvae (Diptera: Culicidae). The extracts gave different levels and rate of mortality of the larvae. Some (methanol extract of V. trifolia leaves, acetone extracts of stem bark and leaves of V. schiliebenii, acetone extract of root bark of V. payos) caused 100% mortality at 100ppm in 72h, with those of V. schiliebenii and V. …

Go to article

First Record Of Calophya Schini (Hemiptera: Calophyidae) In Ethiopia And Kenya, William A. Overholt, Robert S. Copeland, Susan E. Halbert Jan 2013

First Record Of Calophya Schini (Hemiptera: Calophyidae) In Ethiopia And Kenya, William A. Overholt, Robert S. Copeland, Susan E. Halbert

All Peer-Reviewed Publications

A South American leaf galling psyllid, Calophya schini Tuthill, has recently been discovered attacking the South American tree Schinus molle L. in Kenya and Ethiopia. This represents the first record of the psyllid in each country and the only record of C. schini in Africa outside of South Africa. In Kenya, the psyllid was parasitized by an unidentified tetrastichine (Eulophidae), probably of the genus Tamarixia, while in Ethiopia C. schini nymphs were heavily parasitized by an unidentified hymenopteran. Copyright © icipe 2013.

Go to article

Occurrence, Diversity And Pattern Of Damage Of Oplostomus Species (Coleoptera: Scarabaeidae), Honey Bee Pests In Kenya, Ayuka T. Fombong, Fiona N. Mumoki, Elliud Muli, Daniel K. Masiga, Richard T. Arbogast, Peter E.A. Teal, Baldwyn Torto Jan 2013

Occurrence, Diversity And Pattern Of Damage Of Oplostomus Species (Coleoptera: Scarabaeidae), Honey Bee Pests In Kenya, Ayuka T. Fombong, Fiona N. Mumoki, Elliud Muli, Daniel K. Masiga, Richard T. Arbogast, Peter E.A. Teal, Baldwyn Torto

All Peer-Reviewed Publications

Several arthropod pests including the hive beetles Aethina tumida and Oplostomus haroldi and the ectoparasite Varroa destructor have recently been identified as associated with honey bee colonies in Kenya. Here, we report the first documentation of Oplostomus fuligineus in Kenya, a related scarab of O. haroldi, and distribution, diversity and pattern of damage of the two scarab species on honey bee colonies. Sequence analyses of mitochondrial cytochrome oxidase I gene revealed that there was sufficient sequence divergence to separate both Oplostomus beetles. The same molecular marker separated O. haroldi according to place of origin in Kenya. We further show from …

Go to article

Common Host-Derived Chemicals Increase Catches Of Disease-Transmitting Mosquitoes And Can Improve Early Warning Systems For Rift Valley Fever Virus, David P. Tchouassi, Rosemary Sang, Catherine L. Sole, Armanda D.S. Bastos, Peter E.A. Teal, Christian Borgemeister, Baldwyn Torto Jan 2013

Common Host-Derived Chemicals Increase Catches Of Disease-Transmitting Mosquitoes And Can Improve Early Warning Systems For Rift Valley Fever Virus, David P. Tchouassi, Rosemary Sang, Catherine L. Sole, Armanda D.S. Bastos, Peter E.A. Teal, Christian Borgemeister, Baldwyn Torto

All Peer-Reviewed Publications

Rift Valley fever (RVF), a mosquito-borne zoonosis, is a major public health and veterinary problem in sub-Saharan Africa. Surveillance to monitor mosquito populations during the inter-epidemic period (IEP) and viral activity in these vectors is critical to informing public health decisions for early warning and control of the disease. Using a combination of field bioassays, electrophysiological and chemical analyses we demonstrated that skin-derived aldehydes (heptanal, octanal, nonanal, decanal) common to RVF virus (RVFV) hosts including sheep, cow, donkey, goat and human serve as potent attractants for RVFV mosquito vectors. Furthermore, a blend formulated from the four aldehydes and combined with …

Go to article

Chemical Communication In The Honey Bee Scarab Pest Oplostomus Haroldi: Role Of (Z)-9-Pentacosene, Ayuka T. Fombong, Peter E.A. Teal, Richard T. Arbogast, Paul N. Ndegwa, Lucy W. Irungu, Baldwyn Torto Dec 2012

Chemical Communication In The Honey Bee Scarab Pest Oplostomus Haroldi: Role Of (Z)-9-Pentacosene, Ayuka T. Fombong, Peter E.A. Teal, Richard T. Arbogast, Paul N. Ndegwa, Lucy W. Irungu, Baldwyn Torto

All Peer-Reviewed Publications

Oplostomus haroldi Witte belongs to a unique genus of afro-tropical scarabs that have associations with honey bee colonies, from which they derive vital nutrients. Although the attributes of the honey bee nest impose barriers to communication among nest invaders, this beetle still is able to detect conspecific mates for reproduction. Here, we show, through behavioral studies, that cuticular lipids serve as mate discrimination cues in this beetle. We observed five steps during mating: arrestment, alignment, mounting, and copulation, and a post-copulatory stage, lasting ~40-70 % of the total mating duration, that suggested mate guarding. Chemical analysis identified the same nine …

Go to article

Disentangling Dispersal, Vicariance And Adaptive Radiation Patterns: A Case Study Using Armyworms In The Pest Genus Spodoptera (Lepidoptera: Noctuidae), Gael J. Kergoat, Dorothy P. Prowell, Bruno P. Le Ru, Andrew Mitchell, Pascaline Dumas, Anne Laure Clamens, Fabien L. Condamine, Jean François Silvain Dec 2012

Disentangling Dispersal, Vicariance And Adaptive Radiation Patterns: A Case Study Using Armyworms In The Pest Genus Spodoptera (Lepidoptera: Noctuidae), Gael J. Kergoat, Dorothy P. Prowell, Bruno P. Le Ru, Andrew Mitchell, Pascaline Dumas, Anne Laure Clamens, Fabien L. Condamine, Jean François Silvain

All Peer-Reviewed Publications

Thanks to the recent development of integrative approaches that combine dated phylogenies with models of biogeographic evolution, it is becoming more feasible to assess the roles of dispersal and vicariance in creating complex patterns of geographical distribution. However, the historical biogeography of taxa with good dispersal abilities, like birds or flying insects, still remains largely unknown because of the lack of complete phylogenies accompanied by robust estimates of divergence times. In this study, we investigate the evolution and historical biogeography of the globally distributed pest genus Spodoptera (Lepidoptera: Noctuidae) using complete taxon sampling and an extensive set of analyses. Through …

Go to article

First Prev Next Last