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Full-Text Articles in Entomology

Semiochemicals From Herbivory Induced Cotton Plants Enhance The Foraging Behavior Of The Cotton Boll Weevil, Anthonomus Grandis, D. M. Magalhães, M. Borges, R. A. Laumann, E. R. Sujii, P. Mayon, J. C. Caulfield, C. A.O. Midega, Z. R. Khan, J. A. Pickett, M. A. Birkett, M. C. Blassioli-Moraes Dec 2012

Semiochemicals From Herbivory Induced Cotton Plants Enhance The Foraging Behavior Of The Cotton Boll Weevil, Anthonomus Grandis, D. M. Magalhães, M. Borges, R. A. Laumann, E. R. Sujii, P. Mayon, J. C. Caulfield, C. A.O. Midega, Z. R. Khan, J. A. Pickett, M. A. Birkett, M. C. Blassioli-Moraes

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The boll weevil, Anthonomus grandis, has been monitored through deployment of traps baited with aggregation pheromone components. However, field studies have shown that the number of insects caught in these traps is significantly reduced during cotton squaring, suggesting that volatiles produced by plants at this phenological stage may be involved in attraction. Here, we evaluated the chemical profile of volatile organic compounds (VOCs) emitted by undamaged or damaged cotton plants at different phenological stages, under different infestation conditions, and determined the attractiveness of these VOCs to adults of A. grandis. In addition, we investigated whether or not VOCs released by …

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Species Richness And Nest Dispersion Of Some Tropical Meliponine Bees (Apidae: Meliponinae) In Six Habitat Types In The Kakamega Forest, Western Kenya, Kiatoko Nkoba, Suresh Kumar Raina, Elluid Muli, Klaus Mithofer, Jones Mueke Dec 2012

Species Richness And Nest Dispersion Of Some Tropical Meliponine Bees (Apidae: Meliponinae) In Six Habitat Types In The Kakamega Forest, Western Kenya, Kiatoko Nkoba, Suresh Kumar Raina, Elluid Muli, Klaus Mithofer, Jones Mueke

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A study to determine the species richness and spatial distribution of five meliponine bee species in three different habitats in the Kakamega forest was undertaken for the first time. Two forest (indigenous and mixed indigenous) and two grassland (with Eucalyptus spp. trees and indigenous trees) types, along with homesteads (in the vicinity of mixed indigenous forest and indigenous forest, respectively), were surveyed. Line transect methods were used in the nest survey in each habitat. The highest number of species was recorded in the indigenous forest, while no nest was discovered in the grassland with Eucalyptus spp. trees. The mean number …

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Farmers' Perceptions Of Cotton Pests And Their Management In Western Kenya, Charles A.O. Midega, Isaac M. Nyang'au, Jimmy Pittchar, Michael A. Birkett, John A. Pickett, Miguel Borges, Zeyaur R. Khan Dec 2012

Farmers' Perceptions Of Cotton Pests And Their Management In Western Kenya, Charles A.O. Midega, Isaac M. Nyang'au, Jimmy Pittchar, Michael A. Birkett, John A. Pickett, Miguel Borges, Zeyaur R. Khan

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Cotton (Gossypium hirsutum L.) production in western Kenya is severely affected by insect pests, resulting in poor yields in spite of the growing demand for the commodity. One of the key constraints to establishing effective pest management approaches for smallholder farmers is the lack of adequate information about farmers' knowledge, perceptions and practices in pest management. This study was therefore conducted to (1) evaluate farmers' knowledge and perceptions of cotton pests; (2) examine farmers' current practices in managing cotton pests; (3) identify pest management challenges and intervention opportunities in order to develop efficient integrated pest management (IPM) approaches. A total …

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Secondary Contact And Admixture Between Independently Invading Populations Of The Western Corn Rootworm, Diabrotica Virgifera Virgifera In Europe, Gérald Bermond, Marc Ciosi, Eric Lombaert, Aurélie Blin, Marco Boriani, Lorenzo Furlan, Stefan Toepfer, Thomas Guillemaud Nov 2012

Secondary Contact And Admixture Between Independently Invading Populations Of The Western Corn Rootworm, Diabrotica Virgifera Virgifera In Europe, Gérald Bermond, Marc Ciosi, Eric Lombaert, Aurélie Blin, Marco Boriani, Lorenzo Furlan, Stefan Toepfer, Thomas Guillemaud

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The western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), is one of the most destructive pests of corn in North America and is currently invading Europe. The two major invasive outbreaks of rootworm in Europe have occurred, in North-West Italy and in Central and South-Eastern Europe. These two outbreaks originated from independent introductions from North America. Secondary contact probably occurred in North Italy between these two outbreaks, in 2008. We used 13 microsatellite markers to conduct a population genetics study, to demonstrate that this geographic contact resulted in a zone of admixture in the Italian region of Veneto. We show …

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Sheep Skin Odor Improves Trap Captures Of Mosquito Vectors Of Rift Valley Fever, David P. Tchouassi, Rosemary Sang, Catherine L. Sole, Armanda D.S. Bastos, Klaus Mithoefer, Baldwyn Torto Nov 2012

Sheep Skin Odor Improves Trap Captures Of Mosquito Vectors Of Rift Valley Fever, David P. Tchouassi, Rosemary Sang, Catherine L. Sole, Armanda D.S. Bastos, Klaus Mithoefer, Baldwyn Torto

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In recent years, the East African region has seen an increase in arboviral diseases transmitted by blood-feeding arthropods. Effective surveillance to monitor and reduce incidence of these infections requires the use of appropriate vector sampling tools. Here, trapped skin volatiles on fur from sheep, a known preferred host of mosquito vectors of Rift Valley fever virus (RVFV), were used with a standard CDC light trap to improve catches of mosquito vectors. We tested the standard CDC light trap alone (L), and baited with (a) CO2 (LC), (b) animal volatiles (LF), and (c) CO2 plus animal volatiles (LCF) in two highly …

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Viral Metagenomics Demonstrates That Domestic Pigs Are A Potential Reservoir For Ndumu Virus, Charles Masembe, George Michuki, Maria Onyango, Cecilia Rumberia, Martin Norling, Richard P. Bishop, Appolinaire Djikeng, Stephen J. Kemp, Alan Orth, Robert A. Skilton, Karl Ståhl, Anne Fischer Sep 2012

Viral Metagenomics Demonstrates That Domestic Pigs Are A Potential Reservoir For Ndumu Virus, Charles Masembe, George Michuki, Maria Onyango, Cecilia Rumberia, Martin Norling, Richard P. Bishop, Appolinaire Djikeng, Stephen J. Kemp, Alan Orth, Robert A. Skilton, Karl Ståhl, Anne Fischer

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Background: The rising demand for pork has resulted in a massive expansion of pig production in Uganda. This has resulted in increased contact between humans and pigs. Pigs can act as reservoirs for emerging infectious diseases. Therefore identification of potential zoonotic pathogens is important for public health surveillance. In this study, during a routine general surveillance for African swine fever, domestic pigs from Uganda were screened for the presence of RNA and DNA viruses using a high-throughput pyrosequencing method. Findings. Serum samples from 16 domestic pigs were collected from five regions in Uganda and pooled accordingly. Genomic DNA and RNA …

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Evaluation Of Low Density Polyethylene And Nylon For Delivery Of Synthetic Mosquito Attractants, Wolfgang R. Mukabana, Collins K. Mweresa, Philemon Omusula, Benedict O. Orindi, Renate C. Smallegange, Joop Ja Van Loon, Willem Takken Sep 2012

Evaluation Of Low Density Polyethylene And Nylon For Delivery Of Synthetic Mosquito Attractants, Wolfgang R. Mukabana, Collins K. Mweresa, Philemon Omusula, Benedict O. Orindi, Renate C. Smallegange, Joop Ja Van Loon, Willem Takken

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Abstract. Background: Synthetic odour baits present an unexploited potential for sampling, surveillance and control of malaria and other mosquito vectors. However, application of such baits is impeded by the unavailability of robust odour delivery devices that perform reliably under field conditions. In the present study the suitability of low density polyethylene (LDPE) and nylon strips for dispensing synthetic attractants of host-seeking Anopheles gambiae mosquitoes was evaluated. Methods. Baseline experiments assessed the numbers of An. gambiae mosquitoes caught in response to low density polyethylene (LDPE) sachets filled with attractants, attractant-treated nylon strips, control LDPE sachets, and control nylon strips placed in …

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Taxonomic Identity Of The Invasive Fruit Fly Pest, Bactrocera Invadens: Concordance In Morphometry And Dna Barcoding, Fathiya M. Khamis, Daniel K. Masiga, Samira A. Mohamed, Daisy Salifu, Marc De Meyer, Sunday Ekesi Sep 2012

Taxonomic Identity Of The Invasive Fruit Fly Pest, Bactrocera Invadens: Concordance In Morphometry And Dna Barcoding, Fathiya M. Khamis, Daniel K. Masiga, Samira A. Mohamed, Daisy Salifu, Marc De Meyer, Sunday Ekesi

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In 2003, a new fruit fly pest species was recorded for the first time in Kenya and has subsequently been found in 28 countries across tropical Africa. The insect was described as Bactrocera invadens, due to its rapid invasion of the African continent. In this study, the morphometry and DNA Barcoding of different populations of B. invadens distributed across the species range of tropical Africa and a sample from the pest's putative aboriginal home of Sri Lanka was investigated. Morphometry using wing veins and tibia length was used to separate B. invadens populations from other closely related Bactrocera species. The …

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Mediation Of A Plant-Spider Association By Specific Volatile Compounds, Ximena J. Nelson, Andrew J. Pratt, Xavier Cheseto, Baldwyn Torto, Robert R. Jackson Sep 2012

Mediation Of A Plant-Spider Association By Specific Volatile Compounds, Ximena J. Nelson, Andrew J. Pratt, Xavier Cheseto, Baldwyn Torto, Robert R. Jackson

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Evarcha culicivora, an East African jumping spider (Salticidae), is the only spider for which there is evidence of innate olfactory affinity for particular plant species. Evarcha culicivora also actively chooses as preferred prey the females of Anopheles mosquitoes, and both sexes of Anopheles are known to visit plants for nectar meals. Here, we identified compounds present in the headspace of one of these species in Kenya, Lantana camara, and then used 11 of these compounds in olfactometer experiments. Our findings show that three terpenes [(E)-β-caryophyllene, α-humulene and 1,8 cineole] can be discriminated by, and are salient to, E. culicivora. The …

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Mass Spectral Determination Of Phenylacetonitrile (Pan) Levels In Body Tissues Of Adult Desert Locust, Schistocerca Gregaria, Peris W. Amwayi, Daniel K. Masiga, Prem Govender, Peter E.A. Teal, Baldwyn Torto Aug 2012

Mass Spectral Determination Of Phenylacetonitrile (Pan) Levels In Body Tissues Of Adult Desert Locust, Schistocerca Gregaria, Peris W. Amwayi, Daniel K. Masiga, Prem Govender, Peter E.A. Teal, Baldwyn Torto

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Wings and legs of the gregarious desert locust, Schistocerca gregaria have been shown to be release sites of phenylacetonitrile (PAN), the major adult male-produced pheromone. However, there is limited information on the distribution of PAN within the locust. Here we show, using gas chromatography-mass spectrometry (GC-MS), that PAN occurs in nearly all body parts of both adult males and females of the locust in varying amounts. PAN was 20-fold more concentrated in males than in females. In females, PAN was concentrated more in the tarsal segments. The greatest amounts of PAN were in 2- and 3-week old female and male …

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Palaeoenvironmental Shifts Drove The Adaptive Radiation Of A Noctuid Stemborer Tribe (Lepidoptera, Noctuidae, Apameini) In The Miocene, Emmanuel F.A. Toussaint, Fabien L. Condamine, Gael J. Kergoat, Claire Capdevielle-Dulac, Jérôme Barbut, Jean François Silvain, Bruno P. Le Ru Jul 2012

Palaeoenvironmental Shifts Drove The Adaptive Radiation Of A Noctuid Stemborer Tribe (Lepidoptera, Noctuidae, Apameini) In The Miocene, Emmanuel F.A. Toussaint, Fabien L. Condamine, Gael J. Kergoat, Claire Capdevielle-Dulac, Jérôme Barbut, Jean François Silvain, Bruno P. Le Ru

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Between the late Oligocene and the early Miocene, climatic changes have shattered the faunal and floral communities and drove the apparition of new ecological niches. Grassland biomes began to supplant forestlands, thus favouring a large-scale ecosystem turnover. The independent adaptive radiations of several mammal lineages through the evolution of key innovations are classic examples of these changes. However, little is known concerning the evolutionary history of other herbivorous groups in relation with this modified environment. It is especially the case in phytophagous insect communities, which have been rarely studied in this context despite their ecological importance. Here, we investigate the …

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Trapping Of Rift Valley Fever (Rvf) Vectors Using Light Emitting Diode (Led) Cdc Traps In Two Arboviral Disease Hot Spots In Kenya, David P. Tchouassi, Rosemary Sang, Catherine L. Sole, Armanda D.S. Bastos, Lee W. Cohnstaedt, Baldwyn Torto May 2012

Trapping Of Rift Valley Fever (Rvf) Vectors Using Light Emitting Diode (Led) Cdc Traps In Two Arboviral Disease Hot Spots In Kenya, David P. Tchouassi, Rosemary Sang, Catherine L. Sole, Armanda D.S. Bastos, Lee W. Cohnstaedt, Baldwyn Torto

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Background: Mosquitoes response to artificial lights including color has been exploited in trap designs for improved sampling of mosquito vectors. Earlier studies suggest that mosquitoes are attracted to specific wavelengths of light and thus the need to refine techniques to increase mosquito captures following the development of super-bright light-emitting diodes (LEDs) which emit narrow wavelengths of light or very specific colors. Therefore, we investigated if LEDs can be effective substitutes for incandescent lamps used in CDC light traps for mosquito surveillance, and if so, determine the best color for attraction of important Rift Valley Fever (RFV) vectors. Methods. The efficiency …

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Integrated Mosquito Larval Source Management Reduces Larval Numbers In Two Highland Villages In Western Kenya, Susan S. Imbahale, Andrew Githeko, Wolfgang R. Mukabana, Willem Takken May 2012

Integrated Mosquito Larval Source Management Reduces Larval Numbers In Two Highland Villages In Western Kenya, Susan S. Imbahale, Andrew Githeko, Wolfgang R. Mukabana, Willem Takken

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Background: In western Kenya, malaria remains one of the major health problems and its control remains an important public health measure. Malaria control is by either use of drugs to treat patients infected with malaria parasites or by controlling the vectors. Vector control may target the free living adult or aquatic (larval) stages of mosquito. The most commonly applied control strategies target indoor resting mosquitoes. However, because mosquitoes spend a considerable time in water, targeting the aquatic stages can complement well with existing adult control measures. Methods: Larval source management (LSM) of malaria vectors was examined in two villages i.e. …

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A Novel Synthetic Odorant Blend For Trapping Of Malaria And Other African Mosquito Species, Wolfgang R. Mukabana, Collins K. Mweresa, Bruno Otieno, Philemon Omusula, Renate C. Smallegange, Joop J.A. Van Loon, Willem Takken Mar 2012

A Novel Synthetic Odorant Blend For Trapping Of Malaria And Other African Mosquito Species, Wolfgang R. Mukabana, Collins K. Mweresa, Bruno Otieno, Philemon Omusula, Renate C. Smallegange, Joop J.A. Van Loon, Willem Takken

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Estimating the biting fraction of mosquitoes is of critical importance for risk assessment of malaria transmission. Here, we present a novel odor-based tool that has been rigorously assessed in semi-field assays and traditional African villages for estimating the number of mosquitoes that enter houses in search of a blood meal. A standard synthetic blend (SB) consisting of ammonia, (S)-lactic acid, tetradecanoic acid, and carbon dioxide was complemented with isovaleric acid, 4,5 dimethylthiazole, 2-methyl-1-butanol, and 3-methyl-1-butanol in various combinations and concentrations, and tested for attractiveness to the malaria mosquito Anopheles gambiae. Compounds were released through low density polyethylene (LDPE) material or …

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Species Composition Of Fruit Flies (Diptera: Tephritidae) In The Citrus Museum At The Agricultural Research Centre (Arc), Kade, Ghana, Caroline Ngichop Foba, Kwame Afreh-Nuamah, Maxwell Kelvin Billah, Daniel Obeng-Ofori Mar 2012

Species Composition Of Fruit Flies (Diptera: Tephritidae) In The Citrus Museum At The Agricultural Research Centre (Arc), Kade, Ghana, Caroline Ngichop Foba, Kwame Afreh-Nuamah, Maxwell Kelvin Billah, Daniel Obeng-Ofori

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To determine species composition of fruit flies on six cultivated varieties of citrus (Late Valencia orange, Pineapple orange, Ovaleto, Mediterranean sweet lemon, Satsuma tangerine and Ortanique orange), a study was conducted at the Agricultural Research Centre, Kade, Ghana. Improvised Lynfield baited traps (methyl eugenol (ME) and citrus juice (CJ)) and McPhail baited traps (trimedlure (TML)) were used. Ripe infested fruits from the selected varieties were also collected and incubated. Tephritid fruit fly species from trapping were identified as Bactrocera invadens Drew, Tsuruta & White, Bactrocera cucurbitae (Coquillet), Ceratitis ditissima Munro, C. anonae Graham, C. capitata (Wiedemann), C. bremii Guerin-Meneville, Dacus …

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Oviposition Induced Volatile Emissions From African Smallholder Farmers' Maize Varieties, Amanuel Tamiru, Toby J.A. Bruce, Charles A.O. Midega, Christine M. Woodcock, Michael A. Birkett, John A. Pickett, Zeyaur R. Khan Mar 2012

Oviposition Induced Volatile Emissions From African Smallholder Farmers' Maize Varieties, Amanuel Tamiru, Toby J.A. Bruce, Charles A.O. Midega, Christine M. Woodcock, Michael A. Birkett, John A. Pickett, Zeyaur R. Khan

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Maize (corn), Zea mays, is a genetically diverse crop, and we have recently shown that certain open pollinated varieties (OPVs) of Latin American origin possess a trait not present in mainstream commercial varieties: they produce volatiles in response to stemborer oviposition that are attractive to stemborer parasitoids. Here, we tested whether a similar tritrophic effect occurs in the African OPVs 'Nyamula' and 'Jowi'. Herbivore induced plant volatiles (HIPVs) were collected from plants exposed to egg deposition by the stemborer Chilo partellus. In a four-arm olfactometer bioassay, the parasitic wasp Cotesia sesamiae preferred samples containing HIPVs from plants with eggs to …

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Life History Of Oplostomus Haroldi (Coleoptera: Scarabaeidae) Under Laboratory Conditions And A Description Of Its Third Instar Larva, Ayuka T. Fombong, Fabian Haas, Paul N. Ndegwa, Lucy W. Irungu Mar 2012

Life History Of Oplostomus Haroldi (Coleoptera: Scarabaeidae) Under Laboratory Conditions And A Description Of Its Third Instar Larva, Ayuka T. Fombong, Fabian Haas, Paul N. Ndegwa, Lucy W. Irungu

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The life history of Oplostomus haroldi (Witte), a recently reported pest of honeybee colonies in East Africa, was studied for the first time under laboratory conditions. Adult O. haroldi collected from beehives in the coastal part of Kenya were reared on a mixture of moist sterilized soil and cow dung. At 25-±-2-°C, 50-±-5% relative humidity and a 10-h light-14-h dark photoperiod, the laid eggs took 11.9-±-1.3 days to hatch into a curved pear-shaped scarabaeiform larva with a well-developed head and thoracic legs. The first, second and third larval instars lasted 14.6-±-2.6, 17.5-±-2.4 and 34.6-±-2.4 days, respectively. The pupal stage, which …

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Seasonal Abundance Of Maiestas Banda (Hemiptera: Cicadellidae), A Vector Of Phytoplasma, And Other Leafhoppers And Planthoppers (Hemiptera: Delphacidae) Associated With Napier Grass (Pennisetum Purpureum) In Kenya, Shinsaku Koji, Satoshi Fujinuma, Charles A.O. Midega, Hassan M. Mohamed, Tadashi Ishikawa, Michael R. Wilson, Manfred Asche, Simon Degelo, Tarô Adati, John A. Pickett, Zeyaur R. Khan Mar 2012

Seasonal Abundance Of Maiestas Banda (Hemiptera: Cicadellidae), A Vector Of Phytoplasma, And Other Leafhoppers And Planthoppers (Hemiptera: Delphacidae) Associated With Napier Grass (Pennisetum Purpureum) In Kenya, Shinsaku Koji, Satoshi Fujinuma, Charles A.O. Midega, Hassan M. Mohamed, Tadashi Ishikawa, Michael R. Wilson, Manfred Asche, Simon Degelo, Tarô Adati, John A. Pickett, Zeyaur R. Khan

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Napier grass (Pennisetum purpureum Schumach), the main fodder crop in eastern Africa, has recently been severely affected by Napier stunt disease, which is caused by phytoplasma. We have recently confirmed that a leafhopper, Maiestas banda (Kramer) transmits phytoplasma in Napier grass in Kenya. Several other species of leafhoppers (Cicadellidae) and planthoppers (Delphacidae) are also associated with Napier grass, and some could be potential vector(s) of phytoplasma, but little is known about phenology and movement activity of these insect groups. We monitored the populations of M. banda and other leafhoppers and planthoppers in Napier grass fields at two sites in western …

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Effect Of Temperature And Relative Humidity On The Development And Fecundity Of Chilo Partellus (Swinhoe) (Lepidoptera: Crambidae), A. Tamiru, E. Getu, B. Jembere, T. Bruce Feb 2012

Effect Of Temperature And Relative Humidity On The Development And Fecundity Of Chilo Partellus (Swinhoe) (Lepidoptera: Crambidae), A. Tamiru, E. Getu, B. Jembere, T. Bruce

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The spotted stemborer, Chilo partellus (Swinhoe) (Lepidoptera: Crambidae), is one of the most important insect pests attacking maize and sorghum in Ethiopia. Recent studies have indicated that the pest is spreading to new locations where it was not reported before. In the current study, laboratory investigations were carried out to determine the combined effect of different levels of relative humidity and temperature regimes on the development and fecundity of C. partellus, as these physical factors are known to play an important role in the life cycle of insects and adaptability to local climate. Developmental time, longevity, potential fecundity and realized …

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Mosquito Species Abundance And Diversity In Malindi, Kenya And Their Potential Implication In Pathogen Transmission, Joseph M. Mwangangi, Janet Midega, Samuel Kahindi, Laban Njoroge, Joseph Nzovu, John Githure, Charles M. Mbogo, John C. Beier Jan 2012

Mosquito Species Abundance And Diversity In Malindi, Kenya And Their Potential Implication In Pathogen Transmission, Joseph M. Mwangangi, Janet Midega, Samuel Kahindi, Laban Njoroge, Joseph Nzovu, John Githure, Charles M. Mbogo, John C. Beier

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Mosquitoes (Diptera: Culicidae) are important vectors of human disease-causing pathogens. Mosquitoes are found both in rural and urban areas. Deteriorating infrastructure, poor access to health, water and sanitation services, increasing population density, and widespread poverty contribute to conditions that modify the environment, which directly influences the risk of disease within the urban and peri-urban ecosystem. The objective of this study was to evaluate the mosquito vector abundance and diversity in urban, peri-urban, and rural strata inMalindi along the Kenya coast. The study was conducted in the coastal district of Malindi between January and December 2005. Three strata were selected which …

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Study On The Microstructure Of African Wild Silk Cocoon Shells And Fibers, Addis Teshome, Fritz Vollrath, Suresh K. Raina, J. M. Kabaru, J. Onyari Jan 2012

Study On The Microstructure Of African Wild Silk Cocoon Shells And Fibers, Addis Teshome, Fritz Vollrath, Suresh K. Raina, J. M. Kabaru, J. Onyari

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Silk fibers and cocoon shells from four African wild silkmoths Gonometa postica, Anaphe panda, Argema mimosae and Epiphora bauhiniae-were studied to gain insight into the structure-property-function relations and potential commercial application. The surface and cross-section of cocoon shells and fibers revealed the presence of prominent structural variations. Cocoon shells were multilayered and porous structures constructed from highly cross-linked fibers that are densely packed within the sericin/gum. Fibers had fibrillar sub-structures running along the fiber axis and with greater number and size of voids. The ecological significance and implication of these structures for further application are discussed. © 2011.

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Large-Scale Use Of Mosquito Larval Source Management For Malaria Control In Africa: A Cost Analysis, Eve Worrall, Ulrike Fillinger Nov 2011

Large-Scale Use Of Mosquito Larval Source Management For Malaria Control In Africa: A Cost Analysis, Eve Worrall, Ulrike Fillinger

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Background: At present, large-scale use of two malaria vector control methods, long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) is being scaled up in Africa with substantial funding from donors. A third vector control method, larval source management (LSM), has been historically very successful and is today widely used for mosquito control globally, except in Africa. With increasing risk of insecticide resistance and a shift to more exophilic vectors, LSM is now under re-evaluation for use against afro-tropical vector species. Here the costs of this intervention were evaluated. Methods. The 'ingredients approach' was used to estimate the economic and …

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Screenhouse Transmission Of Beauveria Bassiana From Infected To Non-Infected Adults Of Banana Weevil, C. A. Omukoko, J. M. Wesonga, E. M. Kahangi, L. S. Wamocho, K. N. Maniania Oct 2011

Screenhouse Transmission Of Beauveria Bassiana From Infected To Non-Infected Adults Of Banana Weevil, C. A. Omukoko, J. M. Wesonga, E. M. Kahangi, L. S. Wamocho, K. N. Maniania

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Laboratory studies have revealed great potential of entomopathogenic fungus Beauveria bassiana for use against the banana weevil, Cosmopolites sordidus, in banana. Adult banana weevils exposed to wet conidia of Beauveria bassiana suffered high mortalities ranging from 50-70% by 40 days post exposure when a concentration of 1×109 was used in the laboratory with three isolates ICIPE 273, M313 and M207 which were selected on the basis of high virulence against C. sordidus and high sporulation. However, impractical field delivery methods and high costs associated with the application of B. bassiana against C. sordidus prevent its use and commercialisation in banana …

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Management Of Alien Invasive Insect Pest Species And Diseases Of Fruits And Vegetables: Experiences From East Africa, B. Nyambo, S. Sevgan, A. Chabi-Olaye, S. Ekesi Oct 2011

Management Of Alien Invasive Insect Pest Species And Diseases Of Fruits And Vegetables: Experiences From East Africa, B. Nyambo, S. Sevgan, A. Chabi-Olaye, S. Ekesi

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The East African region is currently struggling to cope with several alien invasive insect pest species (AIS): the diamondback moth (DBM), fruit flies, Liriomyza leafminers, thrips and spider mites to name just a few. These insect pests have wide host range, are difficult to control with synthetic pesticides, and most are of quarantine status. AIS are becoming frequent pests in horticulture production systems, threat to food security, market access and rural livelihoods. The impact of these pests is aggravated by variability in climatic conditions, few taxonomic expertise for accurate and timely identification of new species, inadequate knowledge on viable alternative …

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Horticultural Pest Management And The African Economy: Successes, Challenges And Opportunities In A Changing Global Environment, S. Ekesi, A. Chabi-Olaye, S. Subramanian, C. Borgemeister Oct 2011

Horticultural Pest Management And The African Economy: Successes, Challenges And Opportunities In A Changing Global Environment, S. Ekesi, A. Chabi-Olaye, S. Subramanian, C. Borgemeister

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In many African countries, horticulture is the fastest growing agricultural sub-sector contributing significantly to national incomes. Diverse vegetables, fruits and spices are grown for domestic and export markets. Horticultural exports in Africa has increased by more than 50% in recent years and currently contributes >20% of agricultural exports by volume and income generation. Despite the growth, production has not kept pace with increasing demand due largely to biotic constraints attributed to arthropod pests. Agricultural research aimed at reducing insect pest damage can lead to increased horticultural production and improved rural livelihoods. icipe in collaboration with National Agricultural Research and Extension …

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Some Like It Hot: The Influence And Implications Of Climate Change On Coffee Berry Borer (Hypothenemus Hampei) And Coffee Production In East Africa, Juliana Jaramillo, Eric Muchugu, Fernando E. Vega, Aaron Davis, Christian Borgemeister, Adenirin Chabi-Olaye Sep 2011

Some Like It Hot: The Influence And Implications Of Climate Change On Coffee Berry Borer (Hypothenemus Hampei) And Coffee Production In East Africa, Juliana Jaramillo, Eric Muchugu, Fernando E. Vega, Aaron Davis, Christian Borgemeister, Adenirin Chabi-Olaye

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The negative effects of climate change are already evident for many of the 25 million coffee farmers across the tropics and the 90 billion dollar (US) coffee industry. The coffee berry borer (Hypothenemus hampei), the most important pest of coffee worldwide, has already benefited from the temperature rise in East Africa: increased damage to coffee crops and expansion in its distribution range have been reported. In order to anticipate threats and prioritize management actions for H. hampei we present here, maps on future distributions of H. hampei in coffee producing areas of East Africa. Using the CLIMEX model we relate …

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The 2007 Rift Valley Fever Outbreak In Sudan, Osama Ahmed Hassan, Clas Ahlm, Rosemary Sang, Magnus Evander Sep 2011

The 2007 Rift Valley Fever Outbreak In Sudan, Osama Ahmed Hassan, Clas Ahlm, Rosemary Sang, Magnus Evander

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Rift Valley fever (RVF) is a neglected, emerging, mosquito-borne disease with severe negative impact on human and animal health and economy. RVF is caused by RVF virus (RVFV) affecting humans and a wide range of animals. The virus is transmitted through bites from mosquitoes and exposure to viremic blood, body fluids, or tissues of infected animals. During 2007 a large RVF outbreak occurred in Sudan with a total of 747 confirmed human cases including 230 deaths (case fatality 30.8%); although it has been estimated 75,000 were infected. It was most severe in White Nile, El Gezira, and Sennar states near …

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Vegetation And The Importance Of Insecticide-Treated Target Siting For Control Of Glossina Fuscipes Fuscipes, Johan Esterhuizen, Basilio Njiru, Glyn A. Vale, Michael J. Lehane, Stephen J. Torr Sep 2011

Vegetation And The Importance Of Insecticide-Treated Target Siting For Control Of Glossina Fuscipes Fuscipes, Johan Esterhuizen, Basilio Njiru, Glyn A. Vale, Michael J. Lehane, Stephen J. Torr

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Control of tsetse flies using insecticide-treated targets is often hampered by vegetation re-growth and encroachment which obscures a target and renders it less effective. Potentially this is of particular concern for the newly developed small targets (0.25 high × 0.5 m wide) which show promise for cost-efficient control of Palpalis group tsetse flies. Consequently the performance of a small target was investigated for Glossina fuscipes fuscipes in Kenya, when the target was obscured following the placement of vegetation to simulate various degrees of natural bush encroachment. Catches decreased significantly only when the target was obscured by more than 80%. Even …

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Development Of Environmental Tools For Anopheline Larval Control, Susan S. Imbahale, Collins K. Mweresa, Willem Takken, Wolfgang R. Mukabana Jul 2011

Development Of Environmental Tools For Anopheline Larval Control, Susan S. Imbahale, Collins K. Mweresa, Willem Takken, Wolfgang R. Mukabana

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Background: Malaria mosquitoes spend a considerable part of their life in the aquatic stage, rendering them vulnerable to interventions directed to aquatic habitats. Recent successes of mosquito larval control have been reported using environmental and biological tools. Here, we report the effects of shading by plants and biological control agents on the development and survival of anopheline and culicine mosquito larvae in man-made natural habitats in western Kenya. Trials consisted of environmental manipulation using locally available plants, the introduction of predatory fish and/or the use of Bacillus thuringiensis var. israelensis (Bti) in various combinations. Results: Man-made habitats provided with shade …

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Ultra-Prolonged Activation Of Co2-Sensing Neurons Disorients Mosquitoes, Stephanie Lynn Turner, Nan Li, Tom Guda, John Githure, Ring T. Cardé, Anandasankar Ray Jun 2011

Ultra-Prolonged Activation Of Co2-Sensing Neurons Disorients Mosquitoes, Stephanie Lynn Turner, Nan Li, Tom Guda, John Githure, Ring T. Cardé, Anandasankar Ray

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Carbon dioxide (CO2) present in exhaled air is the most important sensory cue for female blood-feeding mosquitoes, causing activation of long-distance host-seeking flight, navigation towards the vertebrate host 1 and, in the case of Aedes aegypti, increased sensitivity to skin odours2. The CO2 detection machinery is therefore an ideal target to disrupt host seeking. Here we use electrophysiological assays to identify a volatile odorant that causes an unusual, ultra-prolonged activation of CO2-detecting neurons in three major disease-transmitting mosquitoes: Anopheles gambiae, Culex quinquefasciatus and A. aegypti. Importantly, ultra-prolonged activation of these neurons severely compromises their ability subsequently to detect CO2 for …

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