Abstract: Tomato is one of the most important vegetable crops grown in Ethiopia. Its production is constrained by arthropod pests and diseases. Fruit borer (Helicoverpa armigera), Whiteflies (Bemisia tabaci), Aphids (Aphis spp), leafminer (Tuta absoluta), Serpentine leafminer (Liriomyza sp), Thrips sp and two spotted spidemites (Tetranchus urticae Koch) are the major economic pests recorded in the study area. The research was initiated to evaluate the potential of intercropping and plant ext...
Abstract: In sub-Saharan Africa, three fruit dlies: Ceratitis cosyra (Walker, C. fasciventris (Bezzi) and C. capitata (Wiedemann) (Diptera: Tephritidae) are important pests of commercial fruits. C. cosyra and C. fasciventris affect.....(continue from the attached PDF)
Abstract: The study was conducted in western Kenya, a prime banana growing area during the period of May 1996 to February 1999. The objectives were to control the banana weevil and parasitic nematodes with neem materials, thereby reducing yield losses and contributing to sustainable banana production. The repellent, antifeedant, ovipositional deterrent, and growth inhibitory effects of powdered neem seed (NSP), kernel (NKP), cake (NC) and neem oil (NO) on Cosmopolites sordidus and its popula...
Abstract: Infestation by insect pests and infection of disease causing pathogens are among the major biotic constraints hindering production, profitability and contribution of citrus to economic development. The African citrus triozid (ACT), Trioza erytreae (Del Guerico) (Hemiptera: Triozidae) and the Asian citrus psyllid (ACP) Diaphorina citri (Kuwayama) (Hemiptera: Liviidae), known vectors of Candidatus Liberibacter spp. pathogens, causal agents of the incurable and deadly citrus greening ...
Abstract: The research described in this thesis focused on the characterization of some of the factors that influence disease assessment, development and expression of resistance in wheat cultivars to septoria tritici blotch. Earliness appeared to have a strong effect and tallness a small effect on disease severity (DS). A regression equation derived was used to correct the DS in the entries. Another method that gave good disease assessment was to group the cultivars according to their earli...
Abstract: The Lepidopteran stemborer Chilo partellus is a key constraint to cereal production in most resource-poor farming systems as it causes damage to the crop, accruing up to 80%. When plants are damaged by herbivorous insects, they produce herbivore-induced plant volatiles (HIPVs) which can act as repellants for these insect pests and as attractants for organisms antagonistic to these pests (parasitic wasps and predators). Plants can also produce signals that warn other plants of impen...
Abstract: Lepidopteran stem borers are among field insect pests responsible for the low maize production in sub-Saharan Africa. In Kenya, Chilo partellus Swinhoe (Pyralidae), Busseola fusca Fuller (Noctuidae) and Sesamia calamistis Hampson (Noctuidae) constitute the major proportion of stemborer community. Concerted efforts to reduce stemborer populations in maize fields have been emphasized without a good understanding of potential losses associated with damage by respective stemborer speci...
Abstract: This study was undertaken to establish the effect of temperature on the development and survival of B. fusca, S. calamistis and C. partellus and their larval parasitoids The stem borers and the larval parasitoids were reared at 200C, 250C, 280C and 300C and their development time, survival, fecundity and longevity were recorded. These parameters were subjected to analysis of variance (ANOVA) in General Linear Model (GLM). Results showed that development of stem borer larvae varied ...
Abstract: The two initial objectives of this research project were (1) to obtain a detailed chemical description of secretions from the accessory reproductive glands CARGs) of the male desert locust, . Schistocerca gregaria Forskal, and (.2 ) to identify the chemical nature of the spermatophore and seminal fluids in order to obtain a better understanding of the roles of individ~al ARG secretions in their formation. The secretions of the 16 pairs of ARGs were subjected to disc gel electrophor...
Abstract: The ectoparasitic mite Varroa destructor is one of the parasiteglobally reported affecting honeybee healthand causing high colony losses.Of notable importance is the associationof the mite with viruses and their transmission to honeybees which causesgreatharm to bees. Kenyan beekeepers have reportedthat bee populationshave been ondecline in recent years and therefore the need for research to establish whether Varroa destructoris negativelyaffectinghoneybee survival and development....
Abstract: Liromyza trifolii Burgess (Diptera: Agromyzidae) belongs to a group of phytophagous insects whose larvae feed inside the leaf of a wide variety of horticultural crops like snow peas (Pisum sativum L.), french beans (Phaseolus vulgaris L.), potatoes (Solanum tuberosum L.) and a variety of flowers. Studies were carried out at seven constant temperatures of 10, 15, 18, 20, 25, 30 and 350C to determine the effect of temperature on life history traits to determine the intrinsic rate of ...
Abstract: Liriomyza leafminers species are exotic pests of horticultural crops in Africa. The most economically important species include Liriomyza sativae (Blanchard), L. trifolii (Burgess) and L. huidobrensis (Blanchard) (Diptera: Agromyzidae) which are major pests of many vegetables and ornamental crops worldwide. In Kenya, production of horticultural crops is severely constrained by infestation of Liriomyza leafminer flies (LMF). As a result, farmers increasingly use synthetic chemical i...
Abstract: Chilo partellus (Swinhoe) (Lepidoptera: Crambidae) is a major pest and a threat to cultivated poaceous plants in many pa1ts of Africa. The adverse ecological and environmental effects as well as the cost of chemical insecticides commonly used in its control, besides its limitations makes it necessary to explore environmentally friendly control methods. Classical biological control is one important approach in the control of exotic pests. A larval parasitoid Cotesia jlavipes Cameron...
Abstract: French bean is the most important export vegetable crop cultivated in Kenya. Pests and diseases are the major constrains to its production. The major pests of French beans are bean flies, thrips, and bean aphids. Amongst these pests, thrips are the most notorious and account for 63 – 68% yield loss of fresh marketable pods. Frankliniella occidentalis is the most widespread thrips species which has developed resistance to the commonly used synthetic pesticides. Farmers rely heavil...
Abstract: Sericulture (Silk farming) is the rearing of silk moths for the production of raw silk. Silk farming originated from China where it was secretly practiced for many years before spreading to other parts of the world. Silk moths are grouped into mulberry silk moths (domesticated) and wild silk moths. Silk moth cocoon has a double filament made of insoluble protein known as fibroin which is embedded in a water soluble protein called sericin. Prior to processing cocoons, are boiled in ...