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Full-Text Articles in Life Sciences

Molecular Mapping Of Qtls For Domestication-Related Traits In Cowpea (V. Unguiculata (L.) Walp.), Mebeaselassie Andargie, Remy S. Pasquet, Bhavani S. Gowda, Geoffrey M. Muluvi, Michael P. Timko Dec 2014

Molecular Mapping Of Qtls For Domestication-Related Traits In Cowpea (V. Unguiculata (L.) Walp.), Mebeaselassie Andargie, Remy S. Pasquet, Bhavani S. Gowda, Geoffrey M. Muluvi, Michael P. Timko

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Understanding the genetic basis underlying domestication-related traits (DRTs) of cowpea (Vigna unguiculata (L.) Walp.) is important since the genome has experienced divergent domestication and in addition it is also useful to utilize the wild germplasm efficiently for improving different traits of the cultivated cowpea. Quantitative trait loci (QTLs) for DRTs were identified in a population of 159 F7 recombinant inbred lines derived from a cross between a domesticated cowpea (V. unguiculata (L.) Walp.) variety, 524B, and a wild accession, 219. Using the constructed linkage map, QTLs for 10 DRTs were analysed and mapped. QTLs for seed, pod and flower related …

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Spiroacetals In The Colonization Behaviour Of The Coffee Berry Borer: A 'Push-Pull' System, Teresiah Nyambura Njihia, Juliana Jaramillo, Lucy Murungi, Dickson Mwenda, Benedict Orindi, Hans Michael Poehling, Baldwyn Torto Nov 2014

Spiroacetals In The Colonization Behaviour Of The Coffee Berry Borer: A 'Push-Pull' System, Teresiah Nyambura Njihia, Juliana Jaramillo, Lucy Murungi, Dickson Mwenda, Benedict Orindi, Hans Michael Poehling, Baldwyn Torto

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Coffee berries are known to release several volatile organic compounds, among which is the spiroacetal, conophthorin, an attractant for the coffee berry borer Hypothenemus hampei. Elucidating the effects of other spiroacetals released by coffee berries is critical to understanding their chemo-ecological roles in the host discrimination and colonization process of the coffee berry borer, and also for their potential use in the management of this pest. Here, we show that the coffee berry spiroacetals frontalin and 1,6-dioxaspiro [4.5] decane (referred thereafter as brocain), are also used as semiochemicals by the coffee berry borer for host colonization. Bioassays and chemical analyses …

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Occurrence Of Rift Valley Fever In Cattle In Ijara District, Kenya, Nelson O. Owange, William O. Ogara, Hippolyte Affognon, Gathura B. Peter, Jacqueline Kasiiti, Sam Okuthe, W. Onyango-Ouma, Tobias Landmann, Rosemary Sang, Murithi Mbabu Nov 2014

Occurrence Of Rift Valley Fever In Cattle In Ijara District, Kenya, Nelson O. Owange, William O. Ogara, Hippolyte Affognon, Gathura B. Peter, Jacqueline Kasiiti, Sam Okuthe, W. Onyango-Ouma, Tobias Landmann, Rosemary Sang, Murithi Mbabu

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Ijara district in Kenya was one of the hotspots of rift valley fever (RVF) during the 2006/2007 outbreak which led to human and animal deaths causing huge economic and public health losses. The main constraint in the control and prevention of RVF is inadequate knowledge on its occurrence during the interepidemic period. This study was aimed at understanding the occurrence of RVF in cattle in Ijara to enable the development of improved community-based disease surveillance, prediction, control and prevention.Six herds each 700-1000 cattle were identified with participatory involvement of locals and project technical team of the project. One animal per …

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Effects Of Endophyte Colonization Of Vicia Faba (Fabaceae) Plants On The Life-History Of Leafminer Parasitoids Phaedrotoma Scabriventris (Hymenoptera: Braconidae) And Diglyphus Isaea (Hymenoptera: Eulophidae), Komivi S. Akutse, Komi K.M. Fiaboe, Johnnie Van Den Berg, Sunday Ekesi, Nguya K. Maniania Oct 2014

Effects Of Endophyte Colonization Of Vicia Faba (Fabaceae) Plants On The Life-History Of Leafminer Parasitoids Phaedrotoma Scabriventris (Hymenoptera: Braconidae) And Diglyphus Isaea (Hymenoptera: Eulophidae), Komivi S. Akutse, Komi K.M. Fiaboe, Johnnie Van Den Berg, Sunday Ekesi, Nguya K. Maniania

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Effects of the fungal endophytes Beauveria bassiana (isolates ICIPE 279, G1LU3, S4SU1) and Hypocrea lixii (isolate F3ST1) on the life-history of Phaedrotoma scabriventris and Diglyphus isaea, parasitoids of the pea leafminer Liriomyza huidobrensis, were studied in the laboratory. Parasitoids were allowed to parasitize 2nd and 3rd instar L. huidobrensis larvae reared on endophytically-inoculated faba bean, Vicia faba . In the control, parasitoids were reared on non-inoculated host plants. Parasitism, pupation, adult emergence and survival were recorded. No significant difference was observed between the bcontrol and the endophyte-inoculated plants in terms of parasitism rates of P. scabriventris (p = 0.68) and …

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Microclimate Modification And Insect Pest Exclusion Using Agronet Improve Pod Yield And Quality Of French Bean, Elisha Otieno Gogo, Mwanarusi Saidi, Jacob Mugwa Ochieng, Thibaud Martin, Vance Baird, Mathieu Ngouajio Oct 2014

Microclimate Modification And Insect Pest Exclusion Using Agronet Improve Pod Yield And Quality Of French Bean, Elisha Otieno Gogo, Mwanarusi Saidi, Jacob Mugwa Ochieng, Thibaud Martin, Vance Baird, Mathieu Ngouajio

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French bean [Phaseolus vulgaris (L.)] is among the leading export vegetable in Africa, mostly produced by small-scale farmers. Unfavorable environmental conditions and heavy infestations by insect pests are among the major constraints limiting production of the crop. Most French bean producers grow their crop in open fields outdoors subject to harsh environmental conditions and repeatedly spray insecticides in a bid to realize high yield. This has led to rejection of some of the produce at the export market as a result of stringent limits on maximum residue levels. Two trials were conducted at the Horticulture Research and Teaching Field, Egerton …

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Stability, Bifurcation And Chaos Analysis Of Vector-Borne Disease Model With Application To Rift Valley Fever, Sansao A. Pedro, Shirley Abelman, Frank T. Ndjomatchoua, Rosemary Sang, Henri E.Z. Tonnang Oct 2014

Stability, Bifurcation And Chaos Analysis Of Vector-Borne Disease Model With Application To Rift Valley Fever, Sansao A. Pedro, Shirley Abelman, Frank T. Ndjomatchoua, Rosemary Sang, Henri E.Z. Tonnang

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This paper investigates a RVF epidemic model by qualitative analysis and numerical simulations. Qualitative analysis have been used to explore the stability dynamics of the equilibrium points while visualization techniques such as bifurcation diagrams, Poincaré maps, maxima return maps and largest Lyapunov exponents are numerically computed to confirm further complexity of these dynamics induced by the seasonal forcing on the mosquitoes oviposition rates. The obtained results show that ordinary differential equation models with external forcing can have rich dynamic behaviour, ranging from bifurcation to strange attractors which may explain the observed fluctuations found in RVF empiric outbreak data, as well …

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Colonization Of Onions By Endophytic Fungi And Their Impacts On The Biology Of Thrips Tabaci, Alexander M. Muvea, Rainer Meyhöfer, Sevgan Subramanian, Hans Michael Poehling, Sunday Ekesi, Nguya K. Maniania Sep 2014

Colonization Of Onions By Endophytic Fungi And Their Impacts On The Biology Of Thrips Tabaci, Alexander M. Muvea, Rainer Meyhöfer, Sevgan Subramanian, Hans Michael Poehling, Sunday Ekesi, Nguya K. Maniania

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Endophytic fungi, which live within host plant tissues without causing any visible symptom of infection, are important mutualists that mediate plant-herbivore interactions. Thrips tabaci (Lindeman) is one of the key pests of onion, Allium cepa L., an economically important agricultural crop cultivated worldwide. However, information on endophyte colonization of onions, and their impacts on the biology of thrips feeding on them, is lacking. We tested the colonization of onion plants by selected fungal endophyte isolates using two inoculation methods. The effects of inoculated endophytes on T. tabaci infesting onion were also examined. Seven fungal endophytes used in our study were …

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Predicting The Impact Of Climate Change On Regional And Seasonal Abundance Of The Mealybug Phenacoccus Solenopsis Tinsley (Hemiptera: Pseudococcidae) Using Temperature-Driven Phenology Model Linked To Gis, Babasaheb B. Fand, Henri E.Z. Tonnang, Mahesh Kumar, Santanu K. Bal, Naveen P. Singh, D. V.K.N. Rao, Ankush L. Kamble, Dhananjay D. Nangare, Paramjit S. Minhas Sep 2014

Predicting The Impact Of Climate Change On Regional And Seasonal Abundance Of The Mealybug Phenacoccus Solenopsis Tinsley (Hemiptera: Pseudococcidae) Using Temperature-Driven Phenology Model Linked To Gis, Babasaheb B. Fand, Henri E.Z. Tonnang, Mahesh Kumar, Santanu K. Bal, Naveen P. Singh, D. V.K.N. Rao, Ankush L. Kamble, Dhananjay D. Nangare, Paramjit S. Minhas

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The mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) is a highly invasive and polyphagous pest of global incidence. The fundamental hypothesis of the present study was that the temperature variations due to global climate change may affect seriously the future distribution and abundance of P. solenopsis, which might further aggravate the crop yield losses. We employed a temperature-based phenology model of P. solenopsis in a geographic information system for mapping population growth potentials of P. solenopsis. The three risk indices viz., establishment risk index, generation index and activity index were computed using interpolated temperature data from worldclim database for current (2000) …

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Pesticide Risks From Fruit And Vegetable Pest Management By Small Farmers In Sub-Saharan Africa. A Review, Hubert De Bon, Joël Huat, Laurent Parrot, Antonio Sinzogan, Thibaud Martin, Eric Malézieux, Jean François Vayssières Sep 2014

Pesticide Risks From Fruit And Vegetable Pest Management By Small Farmers In Sub-Saharan Africa. A Review, Hubert De Bon, Joël Huat, Laurent Parrot, Antonio Sinzogan, Thibaud Martin, Eric Malézieux, Jean François Vayssières

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Chemical control has highly expanded over the last 30 years in sub-Saharan Africa to reduce bio-aggressors on all crops. Pest management of fruits and vegetables by small farmers in sub-Saharan Africa have developed anarchically in a fuzzy regulation framework. Pesticide toxicity and excessive application are often criticized both by farmers and consumers. Here, we review pesticide management in sub-Saharan Africa over the past 30 years. We then propose options to improve and reduce pesticide application, in order to decrease environmental and human hazards. The major points are as follows: (1) global changes in sub-Saharan Africa such as urbanization modify farmer …

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Field Evaluation Of Natural Human Odours And The Biogent-Synthetic Lure In Trapping Aedes Aegypti, Vector Of Dengue And Chikungunya Viruses In Kenya, Eunice A. Owino, Rosemary Sang, Catherine L. Sole, Christian Pirk, Charles Mbogo, Baldwyn Torto Sep 2014

Field Evaluation Of Natural Human Odours And The Biogent-Synthetic Lure In Trapping Aedes Aegypti, Vector Of Dengue And Chikungunya Viruses In Kenya, Eunice A. Owino, Rosemary Sang, Catherine L. Sole, Christian Pirk, Charles Mbogo, Baldwyn Torto

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Background: Methods currently used in sampling adult Aedes aegypti, the main vector of dengue and chikungunya viruses are limited for effective surveillance of the vector and accurate determination of the extent of virus transmission during outbreaks and inter - epidemic periods. Here, we document the use of natural human skin odours in baited traps to improve sampling of adult Ae. aegypti in two different endemic areas of chikungunya and dengue in Kenya - Kilifi and Busia Counties. The chemistry of the volatiles released from human odours and the Biogent (BG)-commercial lure were also compared.

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Vector Competence Of Aedes Aegypti Populations From Kilifi And Nairobi For Dengue 2 Virus And The Influence Of Temperature, Edith Chepkorir, Joel Lutomiah, James Mutisya, Francis Mulwa, Konongoi Limbaso, Benedict Orindi, Zipporah Ng'ang'a, Rosemary Sang Sep 2014

Vector Competence Of Aedes Aegypti Populations From Kilifi And Nairobi For Dengue 2 Virus And The Influence Of Temperature, Edith Chepkorir, Joel Lutomiah, James Mutisya, Francis Mulwa, Konongoi Limbaso, Benedict Orindi, Zipporah Ng'ang'a, Rosemary Sang

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Background: Susceptibility of Ae. aegypti mosquito to dengue virus (DENV) varies geographically and can be influenced by climatic factors such as temperature, which affect the incidence, seasonality and distribution of vector-borne diseases. The first outbreak of dengue fever (DF) in Kenya occured in 1982 in the coastal towns of Malindi and Kilifi. Unlike Nairobi where no active dengue transmission has been reported, DF is currently re-emerging at the Coast causing major outbreaks. This study investigated the vector competence of Ae. aegypti populations from two urban areas, Kilifi (Coast of Kenya) and Nairobi (Central Kenya), for DEN-2 virus and the influence …

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Similar Differentiation Patterns Between Pbp Expression Levels And Pheromone Component Ratios In Two Populations Of Sesamia Nonagrioides, Nicolas Glaser, Brigitte Frérot, Ene Leppik, Christelle Monsempes, Claire Capdevielle-Dulac, Bruno Le Ru, Thomas Lecocq, Myriam Harry, Emmanuelle Jacquin-Joly, Paul Andre Calatayud Aug 2014

Similar Differentiation Patterns Between Pbp Expression Levels And Pheromone Component Ratios In Two Populations Of Sesamia Nonagrioides, Nicolas Glaser, Brigitte Frérot, Ene Leppik, Christelle Monsempes, Claire Capdevielle-Dulac, Bruno Le Ru, Thomas Lecocq, Myriam Harry, Emmanuelle Jacquin-Joly, Paul Andre Calatayud

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Pheromone-binding proteins (PBPs) are thought to contribute to the specificity of the pheromone detection system through an initial selective binding with pheromone molecules. Here, we report different expression levels of PBP transcripts in the antennae of two populations of the stemborer Sesamia nonagrioides (Lepidoptera: Noctuidae), one collected in Europe and one in sub-Saharan Africa. The three PBP transcripts previously identified in this species were found to be expressed in both male and female antennae. Whereas PBP3 did not show any differential expression, PBP1 and PBP2 appeared to be expressed differently according to the population origin and sex. Simultaneously, we measured …

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Push-Pull: A Novel Ipm Strategy For The Green Revolution In Africa, Zeyaur R. Khan, Charles A.O. Midega, Jimmy O. Pittchar, John A. Pickett Aug 2014

Push-Pull: A Novel Ipm Strategy For The Green Revolution In Africa, Zeyaur R. Khan, Charles A.O. Midega, Jimmy O. Pittchar, John A. Pickett

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Africa faces serious challenges in feeding its population, mainly due to poor yields of cereals that serve as both staple and cash crops occasioned by insect pests, weeds, and poor soil fertility, and more recently effects of climate change. A novel IPM approach dubbed push-pull has been developed and implemented in eastern Africa, based on locally available companion plants, that effectively addresses these constraints resulting in substantial grain yield increases. The technology involves intercropping cereal crops with stemborer moth repellent crops (push), the forage legume desmodium or molasses grass, and planting the attractive Napier grass (pull) as a border crop. …

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Development And Optimization Of The Suna Trap As A Tool For Mosquito Monitoring And Control, Alexandra Hiscox, Bruno Otieno, Anthony Kibet, Collins K. Mweresa, Philemon Omusula, Martin Geier, Andreas Rose, Wolfgang R. Mukabana, Willem Takken Jul 2014

Development And Optimization Of The Suna Trap As A Tool For Mosquito Monitoring And Control, Alexandra Hiscox, Bruno Otieno, Anthony Kibet, Collins K. Mweresa, Philemon Omusula, Martin Geier, Andreas Rose, Wolfgang R. Mukabana, Willem Takken

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Background: Monitoring of malaria vector populations provides information about disease transmission risk, as well as measures of the effectiveness of vector control. The Suna trap is introduced and evaluated with regard to its potential as a new, standardized, odour-baited tool for mosquito monitoring and control. Methods. Dual-choice experiments with female Anopheles gambiae sensu lato in a laboratory room and semi-field enclosure, were used to compare catch rates of odour-baited Suna traps and MM-X traps. The relative performance of the Suna trap, CDC light trap and MM-X trap as monitoring tools was assessed inside a human-occupied experimental hut in a semi-field …

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Pyriproxyfen For Mosquito Control: Female Sterilization Or Horizontal Transfer To Oviposition Substrates By Anopheles Gambiae Sensu Stricto And Culex Quinquefasciatus, Oscar Mbare, Steven W. Lindsay, Ulrike Fillinger Jun 2014

Pyriproxyfen For Mosquito Control: Female Sterilization Or Horizontal Transfer To Oviposition Substrates By Anopheles Gambiae Sensu Stricto And Culex Quinquefasciatus, Oscar Mbare, Steven W. Lindsay, Ulrike Fillinger

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Background: The use of gravid mosquitoes as vehicles to auto-disseminate larvicides was recently demonstrated for the transfer of pyriproxyfen (PPF) by container-breeding Aedes mosquitoes and presents an appealing idea to explore for other disease vectors. The success of this approach depends on the female's behaviour, the time of exposure and the amount of PPF that can be carried by an individual. We explore the effect of PPF exposure at seven time points around blood feeding on individual Anopheles gambiae sensu stricto and Culex quinquefasciatus fecundity and ability to transfer in laboratory assays. Method. Mosquitoes were exposed to 2.6 mg PPF …

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Evaluation Of The Influence Of Electric Nets On The Behaviour Of Oviposition Site Seeking Anopheles Gambiae S.S, Sisay Dugassa, Jenny M. Lindh, Steve J. Torr, Steven W. Lindsay, Ulrike Fillinger Jun 2014

Evaluation Of The Influence Of Electric Nets On The Behaviour Of Oviposition Site Seeking Anopheles Gambiae S.S, Sisay Dugassa, Jenny M. Lindh, Steve J. Torr, Steven W. Lindsay, Ulrike Fillinger

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Background: Electric nets (e-nets) are used to analyse the flight behaviour of insects and have been used extensively to study the host-oriented flight of tsetse flies. Recently we adapted this tool to analyse the oviposition behaviour of gravid malaria vectors, Anopheles gambiae s.s., orienting towards aquatic habitats and traps by surrounding an artificial pond with e-nets and collecting electrocuted mosquitoes on sticky boards on the ground next to the nets. Here we study whether e-nets themselves affect the responses of gravid An. gambiae s.s. Methods. Dual-choice experiments were carried out in 80 m2 screened semi-field systems where 200 gravid An. …

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Exploiting Phytochemicals For Developing Sustainable Crop Protection Strategies To Withstand Climate Change: Example From Africa, Zeyaur R. Khan, Charles A.O. Midega, Jimmy O. Pittchar, John A. Pickett Jun 2014

Exploiting Phytochemicals For Developing Sustainable Crop Protection Strategies To Withstand Climate Change: Example From Africa, Zeyaur R. Khan, Charles A.O. Midega, Jimmy O. Pittchar, John A. Pickett

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Africa suffers chronic food insecurity resulting from ravaging effects of insect pests, weeds and poor soil fertility, with rising poverty and increasingly dry and hot weather conditions associated with climate change further aggravating this situation. Scientists at the International Centre of Insect Physiology and Ecology (icipe) together with national and international partners have developed a platform technology, 'push-pull', based on locally available companion plants for integrated management of these constraints by exploiting innate plant defence systems including secondary metabolism. This involves intercropping cereal crops, the main staple and cash crops for millions of smallholder farmers in the continent, with forage …

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Folding Wings Like A Cockroach: A Review Of Transverse Wing Folding Ensign Wasps (Hymenoptera: Evaniidae: Afrevania And Trissevania), István Mikó, Robert S. Copeland, James P. Balhoff, Matthew J. Yoder, Andrew R. Deans May 2014

Folding Wings Like A Cockroach: A Review Of Transverse Wing Folding Ensign Wasps (Hymenoptera: Evaniidae: Afrevania And Trissevania), István Mikó, Robert S. Copeland, James P. Balhoff, Matthew J. Yoder, Andrew R. Deans

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We revise two relatively rare ensign wasp genera, whose species are restricted to Sub-Saharan Africa: Afrevania and Trissevania. Afrevania longipetiolata sp. nov., Trissevania heatherae sp. nov., T. hugoi sp. nov., T. mrimaensis sp. nov. and T. slideri sp. nov. are described, males and females of T. anemotis and Afrevania leroyi are redescribed, and an identification key for Trissevaniini is provided. We argue that Trissevania mrimaensis sp. nov. and T. heatherae sp. nov. populations are vulnerable, given their limited distributions and threats from mining activities in Kenya. We hypothesize that these taxa together comprise a monophyletic lineage, Trissevaniini, tr. nov., the …

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Effects Of The Invasive Tomato Red Spider Mite (Acari: Tetranychidae) On Growth And Leaf Yield Of African Nightshades, Lucy K. Murungi, Daisy Salifu, Peter Masinde, John Wesonga, Aggrey Nyende, Markus Knapp May 2014

Effects Of The Invasive Tomato Red Spider Mite (Acari: Tetranychidae) On Growth And Leaf Yield Of African Nightshades, Lucy K. Murungi, Daisy Salifu, Peter Masinde, John Wesonga, Aggrey Nyende, Markus Knapp

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The tomato red spider mite, Tetranychus evansi Baker and Pritchard, is one of the most serious pests of solanaceous crops in Africa. Field experiments were conducted to investigate its effects on the growth and leaf yield of five African nightshade species viz. Solanum americanum, S. sarrachoides, S. scabrum, S.tarderemotum and S. villosum during the 2008 and 2009 growing seasons. Plants were infested with 2-4 day-old female spider mites which were allowed to multiply. The number of mite motiles increased throughout the growing season in unsprayed plots and this number varied significantly between the African nightshade species. Except for S.sarrachoides, leaf …

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Timid Spider Uses Odor And Visual Cues To Actively Select Protected Nesting Sites Near Ants, Ximena J. Nelson, Robert R. Jackson May 2014

Timid Spider Uses Odor And Visual Cues To Actively Select Protected Nesting Sites Near Ants, Ximena J. Nelson, Robert R. Jackson

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Associations in which a more vulnerable species gains protection by seeking out the company of a pugnacious "protector" species capable of deterring predators are documented among mixed-species groups from various taxa, but experimental studies are rare. We consider an unusual arthropod-based example in which the associate species, Phintella piantensis, is a jumping spider (Salticidae) that associates with the territorial weaver ant Oecophylla smaragdina, which in turn is a potential predator of Phintella. However, the predator we consider in this mixed-species association is Scytodes sp., a spitting spider (Scytodae) that often targets salticids as prey. Scytodes adopts a strategy of building …

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Evaluation Of The Distribution And Impacts Of Parasites, Pathogens, And Pesticides On Honey Bee (Apis Mellifera) Populations In East Africa, Elliud Muli, Harland Patch, Maryann Frazier, James Frazier, Baldwyn Torto, Tracey Baumgarten, Joseph Kilonzo, James Ng Ang A. Kimani, Fiona Mumoki, Daniel Masiga, James Tumlinson, Christina Grozinger Apr 2014

Evaluation Of The Distribution And Impacts Of Parasites, Pathogens, And Pesticides On Honey Bee (Apis Mellifera) Populations In East Africa, Elliud Muli, Harland Patch, Maryann Frazier, James Frazier, Baldwyn Torto, Tracey Baumgarten, Joseph Kilonzo, James Ng Ang A. Kimani, Fiona Mumoki, Daniel Masiga, James Tumlinson, Christina Grozinger

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In East Africa, honey bees (Apis mellifera) provide critical pollination services and income for small-holder farmers and rural families. While honey bee populations in North America and Europe are in decline, little is known about the status of honey bee populations in Africa. We initiated a nationwide survey encompassing 24 locations across Kenya in 2010 to evaluate the numbers and sizes of honey bee colonies, assess the presence of parasites (Varroa mites and Nosema microsporidia) and viruses, identify and quantify pesticide contaminants in hives, and assay for levels of hygienic behavior. Varroa mites were present throughout Kenya, except in the …

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Effects Of Landscape Complexity And Habitat Management On Stemborer Colonization, Parasitism And Damage To Maize, Charles A.O. Midega, Mattias Jonsson, Zeyaur R. Khan, Barbara Ekbom Apr 2014

Effects Of Landscape Complexity And Habitat Management On Stemborer Colonization, Parasitism And Damage To Maize, Charles A.O. Midega, Mattias Jonsson, Zeyaur R. Khan, Barbara Ekbom

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Lepidopteran stemborers are a serious constraint to efficient production of maize in sub-Saharan Africa. One of the most effective ways of managing these pests is through a habitat management system called push-pull. Landscape complexity has been shown to enhance biological control of insect pests, and therefore may influence effectiveness of habitat management systems designed to control pests. We studied the relative importance of the push-pull cropping system as a local effect and proportional cover of grassland as a landscape effect on (i) stemborer population density and damage to maize, and (ii) parasitism and mortality of stemborer life stages in western …

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Human African Trypanosomiasis Research Gets A Boost: Unraveling The Tsetse Genome, Serap Aksoy, Geoffrey Attardo, Matt Berriman, Alan Christoffels, Mike Lehane, Dan Masiga, Yeya Toure Apr 2014

Human African Trypanosomiasis Research Gets A Boost: Unraveling The Tsetse Genome, Serap Aksoy, Geoffrey Attardo, Matt Berriman, Alan Christoffels, Mike Lehane, Dan Masiga, Yeya Toure

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Human African trypanosomiasis (HAT), also known as sleeping sickness, is a neglected disease that impacts 70 million people distributed over 1.55 million km2 in sub-Saharan Africa [1]. Trypanosoma brucei gambiense accounts for almost 90% of the infections in central and western Africa, the remaining infections being from T. b. rhodesiense in eastern Africa [1]. Furthermore, the animal diseases caused by related parasites inflict major economic losses to countries already strained [2]. The parasites are transmitted to the mammalian hosts through the bite of an infected tsetse fly.

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Push-Pull Farming Systems, John A. Pickett, Christine M. Woodcock, Charles A.O. Midega, Zeyaur R. Khan Apr 2014

Push-Pull Farming Systems, John A. Pickett, Christine M. Woodcock, Charles A.O. Midega, Zeyaur R. Khan

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Farming systems for pest control, based on the stimulo-deterrent diversionary strategy or push-pull system, have become an important target for sustainable intensification of food production. A prominent example is push-pull developed in sub-Saharan Africa using a combination of companion plants delivering semiochemicals, as plant secondary metabolites, for smallholder farming cereal production, initially against lepidopterous stem borers. Opportunities are being developed for other regions and farming ecosystems. New semiochemical tools and delivery systems, including GM, are being incorporated to exploit further opportunities for mainstream arable farming systems. By delivering the push and pull effects as secondary metabolites, for example, (E)-4,8-dimethyl-1,3,7-nonatriene repelling …

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Proteins Associated With Sf3a60 In T. Brucei, Benson Nyambega, Claudia Helbig, Daniel K. Masiga, Christine Clayton, Mariano J. Levin Mar 2014

Proteins Associated With Sf3a60 In T. Brucei, Benson Nyambega, Claudia Helbig, Daniel K. Masiga, Christine Clayton, Mariano J. Levin

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Trypanosoma brucei relies on Spliced leader trans splicing to generate functional messenger RNAs. Trans splicing joins the specialized SL exon from the SL RNA to pre-mRNAs and is mediated by the trans-spliceosome, which is made up of small nuclear ribonucleoprotein particles and non-snRNP factors. Although the trans spliceosome is essential for trypanosomatid gene expression, not all spliceosomal protein factors are known and of these, only a few are completely characterized. In this study, we have characterized the trypanosome Splicing Factor, SF3a60, the only currently annotated SF3a component. As expected, epitope-tagged SF3a60 localizes in the trypanosome nucleus. SF3a60 is essential for …

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Specialised Use Of Working Memory By Portia Africana, A Spider-Eating Salticid, Fiona R. Cross, Robert R. Jackson Mar 2014

Specialised Use Of Working Memory By Portia Africana, A Spider-Eating Salticid, Fiona R. Cross, Robert R. Jackson

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Using expectancy-violation methods, we investigated the role of working memory in the predatory strategy of Portia africana, a salticid spider from Kenya that preys by preference on other spiders. One of this predator's tactics is to launch opportunistic leaping attacks on to other spiders in their webs. Focussing on this particular tactic, our experiments began with a test spider on a ramp facing a lure (dead prey spider mounted on a cork disc) that could be reached by leaping. After the test spider faced the lure for 30 s, we blocked the test spider's view of the lure by lowering …

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Development And Assessment Of Plant-Based Synthetic Odor Baits For Surveillance And Control Of Malaria Vectors, Vincent O. Nyasembe, David P. Tchouassi, Hillary K. Kirwa, Woodbridge A. Foster, Peter E.A. Teal, Christian Borgemeister, Baldwyn Torto Feb 2014

Development And Assessment Of Plant-Based Synthetic Odor Baits For Surveillance And Control Of Malaria Vectors, Vincent O. Nyasembe, David P. Tchouassi, Hillary K. Kirwa, Woodbridge A. Foster, Peter E.A. Teal, Christian Borgemeister, Baldwyn Torto

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Background: Recent malaria vector control measures have considerably reduced indoor biting mosquito populations. However, reducing the outdoor biting populations remains a challenge because of the unavailability of appropriate lures to achieve this. This study sought to test the efficacy of plant-based synthetic odor baits in trapping outdoor populations of malaria vectors. Methodology and Principal Finding: Three plant-based lures ((E)-linalool oxide [LO], (E)-linalool oxide and (E)-β-ocimene [LO + OC], and a six-component blend comprising ( E)-linalool oxide, (E)-β-ocimene, hexanal, β-pinene, limonene, and ( E)-β-farnesene [Blend C]), were tested alongside an animal/human-based synthetic lure (comprising heptanal, octanal, nonanal, and decanal [Blend F]) …

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Comparison Of Food-Based Attractants For Bactrocera Invadens (Diptera: Tephritidae) And Evaluation Of Mazoferm - Spinosad Bait Spray For Field Suppression In Mango, Sunday Ekesi, Samira Mohamed, Chrysantus M. Tanga Feb 2014

Comparison Of Food-Based Attractants For Bactrocera Invadens (Diptera: Tephritidae) And Evaluation Of Mazoferm - Spinosad Bait Spray For Field Suppression In Mango, Sunday Ekesi, Samira Mohamed, Chrysantus M. Tanga

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Catches of Bactrocera invadens Drew, Tsuruta, & White (Diptera: Tephritidae) in Multi-lure traps baited with six commercial food-based attractants, Mazoferm E802, Torula yeast, GF-120, Hymlure, Biolure, and Nulure were compared in mango orchards in Kenya. In 2007, Mazoferm E802 and Torula yeast were the most effective attractants and captured 2.4-2.6 times more females and 3.4-4.0 times more males than the standard Nulure. All attractants captured more females than males (ranging from 63 to 74%). In 2008, Mazoferm E802 was the most effective bait capturing 5.6 and 9.1 times more females and males, respectively, than the standard Nulure. Among all the …

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Plasmodium Falciparum Infection Increases Anopheles Gambiae Attraction To Nectar Sources And Sugar Uptake, Vincent O. Nyasembe, Peter E.A. Teal, Patrick Sawa, James H. Tumlinson, Christian Borgemeister, Baldwyn Torto Jan 2014

Plasmodium Falciparum Infection Increases Anopheles Gambiae Attraction To Nectar Sources And Sugar Uptake, Vincent O. Nyasembe, Peter E.A. Teal, Patrick Sawa, James H. Tumlinson, Christian Borgemeister, Baldwyn Torto

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Plasmodium parasites are known to manipulate the behavior of their vectors so as to enhance transmission [1-4]. From an evolutionary standpoint, behavior manipulation by the parasite should expose the vector to limited risk of early mortality while ensuring sufficient energy supply for both it and the vector [5, 6]. However, it is unknown whether this vector manipulation also affects vector-plant interaction and sugar uptake. Here, we show that the attraction of Anopheles gambiae s.s. to plant odors increased by 30% and 24% after infection with the oocyst and sporozoite stages of Plasmodium falciparum, respectively, while probing activity increased by 77% …

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Characterization Of The In Vitro Core Surface Proteome Of Mycoplasma Mycoides Subsp. Mycoides, The Causative Agent Of Contagious Bovine Pleuropneumonia, Ivanka Krasteva, Anne Liljander, Anne Fischer, David G.E. Smith, Neil F. Inglis, Massimo Scacchia, Attilio Pini, Joerg Jores, Flavio Sacchini Jan 2014

Characterization Of The In Vitro Core Surface Proteome Of Mycoplasma Mycoides Subsp. Mycoides, The Causative Agent Of Contagious Bovine Pleuropneumonia, Ivanka Krasteva, Anne Liljander, Anne Fischer, David G.E. Smith, Neil F. Inglis, Massimo Scacchia, Attilio Pini, Joerg Jores, Flavio Sacchini

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Contagious bovine pleuropneumonia (CBPP), caused by Mycoplasma mycoides subsp. mycoides (Mmm) is a severe cattle disease, present in many countries in sub-Saharan Africa. The development of improved diagnostic tests and vaccines for CBPP control remains a research priority. Polyacrylamide gel electrophoresis and mass spectrometry were used to characterize the Triton X-114 soluble proteome of nine Mmm strains isolated from Europe or Africa. Of a total of 250 proteins detected, 67 were present in all strains investigated. Of these, 44 were predicted to be lipoproteins or cytoplasmic membrane-associated proteins and are thus likely to be members of the core in vitro …

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