Abstract: Soybean (Glycine max L.) is among the most economically important legumes that provide more than 1/4 of food (for man) and animal feed. However, its yield is comparatively low, most especially under drought stress. The aim of this study therefore was to assess the ability of Rhizobium spp. and mycorrhizal fungi to enhance the yield, seed size and fatty acid content of soybean grown under semi-arid environment. Rhizobium sp. strain R1 was found to possess nitrogen-fixing gene conife...
Abstract: Kairomones are chemical signals that mediate interspecificinteractions beneficial toorganisms that detect the cues. These attractants can be individual compounds ormixtures of herbivore-induced plant volatiles (HIPVs) or herbivore chemicals such aspheromones, i.e., chemicals mediating intraspecific communication between herbivores.Natural enemies eavesdrop on kairomones during their foraging behaviour, i.e., locationof oviposition sites and feeding resources in nature. Kairomone mi...
Abstract: Megathyrsus maximus is nonnative in the neotropics, with a tall form that is commonly used as a forage grass and a smaller-statured form that is considered invasive in south Texas, USA. Biological control researchers are challenged to find an agent that will attack the short form, but not the desirable tall form in other parts of the neotropics. We conducted molecular analyses on 155 Megathyrsus maximus samples from its native range in Africa and compared them with U.S. short-form ...
Abstract: RNA interference (RNAi) is a phenomenon through which double stranded RNA (dsRNA) induces potent sequence-specific degradation of homologous transcripts. Besides its function in cellular defense and developmental regulation, it has emerged as an invaluable tool for elucidation of gene function and drug target validation. This is particularly useful when substantial genome sequence data are available. Gene silencing using RNAi can aid translation of raw genomic sequence data into bi...
Abstract: The present study aimed at investigating the susceptibility of the microorganisms Pseudomonas aeruginosa, Salmonella typhi, Escherichia coli, Staphylococcus aureus, and Bacillus subtilis to ethanolic extracts of propolis (EEP) from three regions of Kenya (Taita, Tana and Samburu). Propolis was extracted using four different concentrations of ethanol: pure, 70%, 50%, and 30%. Ethanol (70%) and Streptomycin were used as controls. The agar diffusion method using filter paper disks was...
Abstract: Temperature critically affects the performance of entomopathogenic fungi (EPF). Mathematical models are critical tools used in predictive microbiology but are less adopted for EPF. We selected eight nonlinear models to describe thermal biology; minimum (Tmin), optimal (Topt) and maximum (Tmax) thresholds; and maximal growth (Pmax) of EPF. Conidial germination and mycelial growth of Metarhizium anisopliae (ICIPE 7, ICIPE 20, ICIPE 62, ICIPE 69, ICIPE 78) and Beauveria bassiana (ICIP...
Abstract: Many species of thrips (Thysanoptera) in the family Thripidae form mating aggregations, but the adaptive significance of these aggregations and the extent of male and female mate choice is poorly understood. We studied the mating behaviour of the bean flower thrips Megalurothrips sjostedti (Trybom) (Thysanoptera: Thripidae), which forms male aggregations and occurs across sub-Saharan Africa. We tested whether males choose mates by female age or mating status. No-choice mating bioas...
Abstract: The invasion of Africa by the South American leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) has caused a severe threat to the production of tomato, Solanum lycopersicum L. (Solanaceae) crops. The excessive use of pesticides for controlling this pest has increased, together with the associated environmental and human health risks. The parasitoid, Dolichogenedia gelechiidivoris Marsh. (Hymenoptera: Braconidae), has been imported into Africa for classical biological con...
Abstract: Selection of oviposition substrate is critical in holometabolous insects. Female stable fies, Stomoxys calcitrans, locate and select vertebrate herbivore dung in which they lay their eggs. However, the preference for vertebrate herbivore dung by S. calcitrans females, its ftness consequences for ofspring,and the semiochemicals used to locate and select oviposition substrates remain unclear. Using oviposition choice tests and life table bioassays we found that gravid female S. calci...
Abstract: Background: Major constraints to camel production include pests and diseases. In northern Kenya, little information is available about blood-borne pathogens circulating in one-humped camels ( Camelus dromedarius) or their possible transmission by the camel haematophagous ectoparasite, Hippobosca camelina, commonly known as camel ked or camel fly. This study aimed to: (i) identify the presence of potentially insect-vectored pathogens in camels and camel keds, and (ii) assess the pot...
Abstract: It is well established that genetic exchange occurs between Trypanosoma brucei parasites when two stocks are used to infect tsetse flies under laboratory conditions and a number of such crosses have been undertaken [1,2]. Both cross and self-fertilisation can take place [3,4], with the products of mating being the equivalent of F1 progeny in a Mendelian system [2,3]. Recently, analysis of a large collection of independent progeny using a series of polymorphic micro and minisatellit...
Abstract: Background: Pyronaridine–artesunate is a novel artemisinin-based combination therapy. The efficacy and safety of pyronaridine–artesunate were compared with artemether–lumefantrine for the treatment of uncomplicated Plasmodium falciparum malaria in children.Methods: This phase III open-label randomized controlled non-inferiority trial was conducted in Western Kenya.Children aged 6 months to ≤ 12 years with a bodyweight > 5 kg and microscopically confirmed P. falciparum malar...
Abstract: Susceptibility of tsetse flies (Glossina spp.) to trypanosomes of both humans and animals has been associated with the presence of the endosymbiont Sodalis glossinidius. However, intrinsic biological characteristics of the flies and environmental factors can influence the presence of both S. glossinidius and the parasites. It thus remains unclear whether it is the S. glossinidius or other attributes of the flies that explains the apparent association. The objective of this study wa...
Abstract: Background: Animal trypanosomosis is a major cause of economic loss in livestock production in Africa. A suggested control measure is to use breeds with traits of trypanotolerance. The study examines the effect of natural Trypanosoma vivax challenge on haematological parameters in two trypanotolerant cattle [N’Dama and West African Shorthorn (WASH)] herds. Methods: Trypanosoma vivax-specific primers were used to diagnose T. vivax infection in an N’Dama herd at Cape Coast in sou...
Abstract: Associations between the South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), and its native parasitoids need to be updated to increase the implementation of pest control strategies. In this study, T. absoluta-infested tomato plants were collected from three regions in Kenya. The emerged parasitoids were identified, and their abundance was correlated with agroecological parameters, viz. cropping systems, and the abundance of the predator Nesidiocoris t...