Molecular Characterization, Ecology and Pathogens of Honeybees in Newly Established Colonies in Kitui County, a Semi-Arid Ecosystem in Kenya

Abstract

Colony Collapse Disorder, CCD, has led to losses of up to 33% of adult worker bees in Europe and the USA. Its predictors include Nosema, honeybee viruses, Varroa, and overuse of pesticides. The goal of this project is to monitor the CCD predictors in a dry land ecosystem such as Kitui district, taking into account the apicultural practices unique to this continent. Sampling was done from three apiaries in Kitui located 2KM apart. Each apiary had seven of three types of hives; Kenyan Top Bar, Langstroth and log. Thirty bees were sampled from each colony, 10 each for sub- species, virus and Nosema analysis. tRNA ILE xiv -ND2 and intron of EF1α was analysed for sub-species analysis. A portion of the small sub-unit of Nosema rRNA was utilised for Nosema diagnosis. Primers specific for Deformed Wing Virus (DWV), Black Queen Cell Virus (BQCV) and Israeli Acute Paralysis virus (IAPV) were used in virus detection. Results showed that the predominant subspecies of honeybees in Kitui is Apis mellifera scutellata but there is presence of Scutellata-Monticola and Scutellata-Litorea hybrids. Pathogen diagnosis revealed absence of Nosema, BQCV and IAPV. Presence of DWV was confirmed in 39.5% of honeybee colonies but absent in Varroa. Colony growth was shown to be influenced by seasons, type of hive used and forage diversity. The pollen diet was identified as polyfloral, with family-level plant diversity potentially exerting great influence on colony growth. This work demonstrates the key role that the environment plays in honeybee health and growth.