Abstract: The relationship between Pseudotheraptus wayi (cashew pest), Anacardium occidentale (cashew plant), and Oecophylla longinoda (natural enemy) is a trophic interaction that is very important in cashew nut production. However, the chemical ecology of the interaction, specifically between the cashew plant and natural enemy as well as the pest and natural enemy was little investigated. Based on the hypothesis that both interactions were mediated by chemical signals, the objective of thi...
Abstract: This work demonstrates how an integrated approach can be used for controlling Larger Grain Borer (Prostephanus truncatus) in maize (Zea mays L.) using solar disinfestation followed by hermetic storage in Purdue Improved Crop Storage (PICS) bags. PICS bags work by sealing grains in an airtight environment for long-term pest-free storage. In order to provide safe food with no inputs of chemical pesticides, the combination of solar disinfestation and the PICS bagging is likely to be a...
Table of Content List of Tables List of Schemes List of Figures Abstract Chapter One 1.1 General introduction 1.2 Malaria parasite 1.3 Malaria disease 1.4 Malaria vectors 1.5 Malaria control strategies 1.6 Significance of study 1.7 Hypothesis 1.8 Justification 1.9 Objectives of the Study Chapter Two: Literature Review 2.1 Uses of natural products in mosquito control 2.2 The Family Meliaceae 2.3 The Genius Turraea 2.4 Limonoids 2.5 Biosynthesis of limonoids Chapter Three: Experimental 3.1 G...
Abstract: Chilo partellus Swinhoe (Lepidoptera: Crambidae) is an exotic cereal stem borer that was accidentally introduced into Africa from South Eastern Asia early 20th century. It is now widespread in most of the lowland areas of the Eeastern and Southern parts of the African continent. The invasive stem borer C. partellus, has proved to be a highly competitive colonizer in many of the areas it has invaded in eastern and southern Africa, often becoming the most serious stem borer.
Abstract: In a previous study using three plant species (maize, sorghum and Napier grass), naïve gravid B fusca females significantly preferred sorghum and maize over Napier grass for oviposition a phenomenon, which was partly related to plant physical characteristics such as leaf surface texture and sheath toughness. The purpose of this study was therefore to determine the importance of plant chemical characteristics (volatiles as well as surface compounds) in host selection for ovipositio...
Abstract: The efficacy of Limburger cheese as an odour bait for sampling African malaria vectors was evaluated. Studies were done in Suba district, Western Kenya at Lwanda Nyamasare village and in a screen house set up at the Thomas Odhiambo campus of the International Center of Insect Physiology and Ecology (ICIPE). Preliminary investigations compared mosquitoes caught by a Counter Flow Geometry (CFG) trap baited with Limburger cheese, a standard centres for disease control (COC) light trap...
Abstract: Ticks are haematophagous ectoparasites capable of transmitting diseases to vertebrates and, therefore, constitute a threat to human, livestock and wildlife health. Though synthetic chemical acaricides have made a tremendous impact over the years in the control and management of the vector on livestock, ticks have developed resistance to most of them. In addition, the chemicals are toxic to non-target organisms. In some parts of Kenya, powdered parts of some plants, including those ...
Abstract: Maize lethal necrosis (MLN) disease caused by a dual infection of maize with Maize chlorotic mottle virus (MCMV) and any cereal potyvirus such as Sugarcane mosaic virus (SCMV), Maize dwarf mosaic virus (MDMV) or Wheat streak mosaic virus (WSMV) was first reported in Kenya in 2011 in Bomet County. This study was aimed at determining the presence and genetic variability of MCMV and SCMV in cereal crops,wild and domesticated grasses and the spatial distribution of alternative hosts in...
Abstract: Avocado is a horticultural crop of increasing economic importance in Kenya and around the world. Avocado production has been declining partly due to inadequate pollination. This decline in avocado pollination is currently linked to habitat fragmentation and climate change that negatively affects insect pollinators, especially in high altitude areas such as Taita Hills in coastal Kenya. However, there is scarcity of information on avocado flower visiting insects in Taita Hills. The ...
Abstract: Frankliniella schultzei Trybom is an important pest of ornamental and vegetable crops worldwide and a vector of Tospoviruses, which are plant viruses belonging to the family Bunyaviridae. It occurs as two color forms (dark and pale) which are morphologically very similar hence has been considered as one species. However, differences in vector competency and geographic spread has led to debate on whether they are one or separate species. Moreover, evidence is lacking on whether thes...
Abstract: The braconid larval parasitoid Cotesia flavipes Cameron (Hymenoptera: Braconidae) was introduced into Kenya from Pakistan and India for the control of the exotic crambid stem borer Chilo partellus Swinhoe (Lepidoptera: Crambidae). In Africa, maize fields are usually islands surrounded by land occupied by wild gramineous plants. Many of the wild plants harbour borer species not found on crops. It is not known if the exotic parasitoid C. flavipes follows these borers into the wild ha...
Abstract: Xenorhabdus is a bacteria genus of the family Enterobacteriaceae. Bacteria of this genus form a mutualistic relationship with Steinernema entomopathogenic nematodes. More so, their antimicrobial production serves as a potential source of novel antibiotics in the wake of growing antimicrobial resistance. This study aimed to establish the phylogenetic relationship of three Xenorhabdus isolates to the 24 described species of the genus based on the 16s rRNA gene. Secondly, it aimed to ...
Abstract: Anopheles gambiae mosquito, the principle Afro-tropical vector of malaria, has been documented in habitats with heavy metals in excess of natural loads. The mosquito has also displayed resistance to most conventional insecticides, and potential to resist challenges by heavy metals. Investigations were conducted in strains of An. gambiae ss, in which tolerance to cadmium and lead heavy metals were established. This study was undertaken to determine any putative relationship between ...
Abstract: Tsetse flies are important agricultural and medical vectors of African trypanosomes, the causative agents of trypanosomosis in humans and animals. The life cycle of the protozoan parasite Trypanosoma, in its invertebrate vector begins when the tsetse fly feeds on an infected mammalian host. An important step in the establishment of tsetse midgut infection involves transformation of bloodstream-form trypanosomes into procyclic forms. This process is mediated by a wide variety of fac...
Abstract: One of the greatest challenges facing the people of sub-Saharan Africa is the production of sufficient food to feed a rapidly increasing population in the face of dwindling finances. As the population grows at 3% and food production at 2% per annum, an annual shortage of 250 million tons of food is expected by year 2020. The greatest obstacle to increasing the production of maize and sorghum, the staple food in many African communities south of the Sahara, is damage by phytophagous...