Abstract: A comparison of the resistance/susceptibility levels of ten cowpea cultivars to the pod borer Maruca testulalis revealed that VITA l was the most susceptible. TVU 946 most resistant and VITA 5, chola local and kamboinse local rroderately resistant. In all the cultivars which were compared, flowers and pods suffered the heaviest damage compared to the stems. Colonizing responses of M. testulalis namely oviposition, larval orientation, feeding, utilization of ingested food, larval de...
Abstract: One of the most important and largely consumed African Indigenous Vegetables (AIV) is amaranth. It is known to have a high nutritional value, agronomical assets and economic attributes. Amaranth production is however constrained by numerous biotic factors such as insect pests, occurring as a complex of species among which lepidopteran defoliators are found to be the most destructive. Investigations on their bio-ecological and control options were conducted. Field experiments were c...
Abstract: The African mosquito species Anopheles gambiae and An. funestus are ranked high among the world's most efficient vectors of human malaria. Their juvenile stages develop in aquatic environments while adults are terrestrial. Chemical signals guide gravid females of these vectors to their egg-laying sites. Several attributes of a pond including presence of other organisms influence egg hatching success and larval survival. Gravid An. gambiae females strongly discriminate among potenti...
Abstract: This thesis describes the asymmetric phase-transfer catalysed (PTC) Darzens condensation of aldehydes and ketones with the chiral reagents 1-menthyl chloromethanesulphonate, (S)-(-)-N-chloromethylsulphony l-2 -thoxymethylpyrrolidine,(S)-(-)-tert-butyl N-(chloromethylsulphonyl)prolinate and (+)-0-methyl-N-(chloromethylsulphonyl)ephedrine using triethylbenzylammonium chloride (TEBA) as the phase-transfer catalyst.The chiral reagent 1-menthyl chloromethanesulphonate was obtained by th...
Abstract: Hexane, ethyl acetate and methanol extracts of Commiphora swynertonii Burtt., Turraea cormicopia (L), T abyssinica, T. floribunda and Melia volkensii Gurke were tested for anti-tick activity against the larvae and adult Rhipicephalus appendiculatus Neuman using the packet method bioassay. The hydrodistilled oil of the leaves of C. swynertonii was tested for acaricidal and repellency activities against ! adult R. appendiculatus using the packet and climbing bioassay method, respecti...
Abstract: Ticks of the genus Rhipicephalus are important parasites of livestock in the world. Rhipicephalus ticks cause huge economic losses to cattle and have a great capacity to develop resistance to chemical acaricides. There is the need therefore to develop alternative strategies that could complement the existing control methods of this ectoparasite. Entomopathogenic fungi are being considered as a promising option for the control of ticks on-host and off-host. The aim of this study was...
Description: A Thesis Presented to the Faculty of Science of the University of Neuchatel for the degree of Doctor of Philosophy
Abstract: Biometric studies coupled with physiological investigations have made it possible to propose a scheme of post-embryonic development and polymorphism in Macrotermes michaellseni. ...(continue from the attached PDF)
Abstract: The control of Amblyomma variegatum and other economically important ticks, like Rhipicephalus appendicu/atus, has relied mainly on the use of acaricides worldwide. However, due to the drawbacks of chemical control, future tick control will have to move more in the direction of integrated approaches emphasizing more regular use of environmentally-friendly non-chemical methods, such as tick parasitoids. lxodiphagus hookeri, one of the seven species of tick parasitoids known, occurs ...
Abstract: Tsetse flies use olfaction in search for food, mates and larviposition sites. Olfactory proteins [(odorant binding proteins (OBPs), pheromone binding proteins (PBPs), chemosensory protein (CSPs), odorant degrading enzymes (ODEs) and odorant receptors (Ors)], located within the antennae, play key role in this process. In this work, presence of olfactory proteins was investigated by constructing and sequencing cDNA libraries from Glossina pallidipes Austen, antennae; Glossina palpali...
Abstract: Midgut trypanolysin from Glossina morsitans morsitans was isolated by a combination of an anion-exchange and gel permeation chromatography. The trypanolysin activity was recovered in the bound fraction. The native molecular weight of trypanolysin was determined -669kDa. Analysis oftrypanolysin by SDS-PAGE recovered a single sub-unit ofMr-14kDa. The induction of trypanolysin activity by bloodmeal increased gradually reaching a peak at 72-120 h after the bloodmeal, and then decreased...
Abstract: Laboratory investigations were carried out to assess phytophagy and its effects on the biology of phlebotomine sandflies and their capacity to transmit Leishmania parasites. Preliminary trials to determine the optimum working standards in terms of anthrone concentration, exposure period and duration, effect of sandfly species and/or sex and effects of diets on the feeding rate, led to the choice of 1.25% as the concentration (w /v) of anthrone reagent to detect the presence of suga...
Abstract: We have chosen the urine innurioglobulin M (IgM) as system to study glycoprotein biosynthesis and carbohydrate processing. Secreted IgM heavy chain (m) has five glycoasylation sites which location and structures have been determined. chain variable region (VH) ia involved in antigen binding, while the constant region (CH) is responsible for the effect or functions in which the carbohydrate plays an important role.
Abstract: A comparative study of the ecology of mosquito vectors of malaria was carried out in the Parkerra irrigation scheme and the Loboi swamp in Baringo districy, Kenya. The swamp was found to be more productive than the irrigation scheme both in terms of species diversity and the relative abundance of individual mosquito species.
Abstract: The oviposition behaviour of Maruca testul ali s on host plant (cowpea), non-host plant s (cotton and sunhemp), and artificial substrates (filter , butter, crepe, and aluminium foil papers) was observed in laboratory and field. These studies were carried out with the aim of gathe ring data on oviposition behaviour patterns e s pecia l ly on how the ovipositing female inter acts with host pla nts, non- host plants as well as potential artificial oviposition substrates. It was also i...