Abstract: In this study, adsorption of heavy metals (copper, lead, zinc and cadmium) from aqueous solutions was investigated using mangrove biomass from the Kenyan Coast. The efficacy of mangrove biomass on the removal of divalent metal ions from aqueous solutions was investigated in single state in batch mode. Batch experiments involved the study of the effects of initial pH, temperature, initial concentration of the metal ion, adsorbent dosage and contact time on metal ions adsorption. The...
Abstract: Control of disease vectors by use of synthetic chemical pesticides has been associated with a series of problems, including resistance development, environmental pollution, and safety risks for humans and domestic animals. Plant-based products have been used for generations in traditional practices to control different arthropods. These have been used in space or personal protection either to repel the arthropods from distance or to deter them from blood-feeding on contact. In the ...
Abstract: The maize weevil, Sitophilus zeamais (Motchulsky), the lesser grain borer, Rhyzopertha dominica (Fabricius), and the Angoumois grain moth, Sitotroga cerealella (Oliver), are serious pests of stored grain in Kenya. The control of these insect pests relies heavily on the use of synthetic insecticides by better off farmers; but there is an increasing cost of application and erratic supply in developing countries. In addition, small-scale farmers cannot afford these commercial products...
Abstract: Human African Trypanosomiasis (HAT) is present in 36 sub-Saharan African countries. The disease is easier to treat in early stage than late stage when treatment with melarsoprol is responsible for significant fatality. Therefore there is need to develop a diagnostic test for early detection before progression of the disease into the late stage. Currently available tests have poor sensitivity. Thus highly sensitive methods are needed for the detection of the parasite in human blood....
Abstract: The contamination of food is increasingly becoming a concern in developing countries due to the mounting amounts of heavy metals in urban environments. Juices are common beverages in the usual diet and contribute significantly to the nutritional intake of essential and harmful trace elements. Currently, there is inadequate information regarding the amounts of heavy metals in juice from sugarcane produced along rivers in Nairobi city. In the present study, the levels of heavy metals...
Abstract: Eleven species/subspecies belonging to the genus Trypanosoma, cause African Animal Trypanosomiasis (AAT) with Trypanosoma vivax and Trypanosoma congolense being the predominant pathogens. Annually, AAT leads to losses worth 4.5 billion dollars to livestock dependent economies in Sub-Saharan Africa. In order to manage the disease, trypanocidal drugs have been in use. However, parasites resistant to these trypanocides have emerged making the treatment of AAT difficult. Parasite resis...
Abstract: Odor-baited traps (OBTs) are increasingly being considered for use in sampling, surveillance and control of malaria mosquitoes. Most odor baits contain carbon dioxide, which apparently enhances trap catches given its role as a mosquito activator. Unfortunately, organic CO2, which is the most locally amenable source of the gas, must be replaced after each experimental night. This precludes the application of carbon dioxide-based odor baits for prolonged area-wide use. This study exp...
Abstract: Cowpea is a multipurpose legume crop that serves as human food, livestock fodder, and income source and is widely produced in sub-Saharan Africa. Soil fertility and attack by insect pests and diseases are significant limitations to its production. Although farm inputs such as phosphate-rich fertilizers and pesticides can solve the mentioned constraints, they are costly for resource-poor farmers. This study aimed at determining the effect of arbuscular mycorrhizal fungi inoculation ...
Abstract: Rodents are one of the major postharvest pests that affect food security by impacting on both food availability and safety. However, knowledge of the impact of rodents in on-farm maize storage systems in Kenya is limited. A survey was conducted in 2014 with a total of 630 farmers spread across the six maize growing agro-ecological zones (AEZs) to assess postharvest losses magnitudes in on-farm maize storage systems in Kenya, and the contribution of rodents to the losses. Experiment...
Abstract: Tsetse flies are the sole vectors of African trypanosomiasis in humans (sleeping sickness) and animals (nagana). The whole genome sequence of the tsetse fly Glossina morsitans morsitans revealed the presence of putative bracoviral sequences (n = 310) widely spread in the genome. These sequences are similar to those identified in parasitic braconid wasps. Bracoviruses (family Polydnaviridae) encode proteins that lower host immunity allowing for the development of parasitoid larvae i...
Abstract: Glossina brevipalpis is a vector of trypanosomes that cause Animal African Trypanosomiasis. Chemoreception in tsetse flies is critical for identifying larvipositioning sites, hosts and mates. Odorant binding proteins (OBPs) are thought to mediate insect chemoreception by shuttling odours to receptors on olfactory sensory neurons. Little is known about the roles of OBPs in tsetse fly chemoreception. The genome of G. brevipalpis has been sequenced and 28 OBPs identified. This study a...
Abstract: Phytopathogenic fungi and bacteria cause enormous crop yield losses worldwide. Over the years, management of plant pathogens has primarily relied on the use of synthetic chemical antimicrobials and development of disease resistant varieties. Exploration for biologically active compounds from plants with an aim of discovery and development of novel and eco-friendly biopesticides to combat current and emerging phytopathogens has received increased interest in the recent past. This st...
Abstract: Maize is a staple food crop in Kenya with about 90% of the rural households depending on it. However, the grain is vulnerable to degradation by mycotoxin producing fungi in the field and during storage. Mycotoxins produced by these fungi cause significant economic losses and deleterious health effects to humans and animals. Strategies such as storage of maize in hermetic bags have been developed to reduce post-harvest grain losses due to pest attack, fungal growth and mycotoxin con...
Abstract: In this study, carried out in Nguruman, southwestern Kenya, 10 bee species were identified as eggplant pollinators. Their foraging behaviour was shown to be affected by the prevailing ambient temperature and not time of the day or the number of flowers per square meter in the eggplant fields. Only 2 bee species, Xylocopa caffra and Narnia sp., visited the eggplant blossoms at a great frequency. Their pollinator effectiveness was determined in two eggplant cultivars (the Black Beaut...
Abstract: For centuries, maize producers in sub-Saharan Africa have been plagued by post-harvest losses from insect infestation and mould infections, with small-scale producers representing the most vulnerable populations. Participatory on-farm trials were conducted to assess the effectiveness of triple layer hermetic (PICS™) bags for storage of maize in small-scale farmers’ stores in rural villages in Makueni County,Kenya. PICS bags are three-layer hermetic bag-system that forms a barri...