Development of plant based biopesticide for bee diseases and pests

Plant-based biopesticides are being developed for control of bee pests and diseases. Plant extracts are evaluated for effectiveness against selected honeybee pests and safety to non target organisms and the environment. The effective and non-toxic plant extracts are formulated, validated, protected by patent and registered with relevant bodies. Overall, 200,000 packaged pieces of bee pest and disease control products will be produced and provided to beekeepers/farmers in the 5 countries in Africa. Commercialization of the plant-derived bee pest and disease control products will be initiated in partnership with the private sector and rural communities will undertake commercial cultivation and processing of the pest control plants. This project activity is important because synthetic acaricides that have been used in the control of bee pests and diseases have had significant drawbacks that include high toxicity, contamination of honey, wax and pollen, and development of pest and disease resistant strains. It is important that beekeepers have access to new control tactics that do not harm bees or contaminate hive products. Plant-essential oils are now recognised as important alternatives. For instance, thymol, a constituent of the traditionally used plant, thyme (Thymus vulgaris), has increasingly been widely used in management and control of bee pests and diseases particularly in developed countries. Currently, it is the major constituent in a number of commercial products for bee pest and disease control such as Api Life VAR, Thymovar and Apiguard that have been registered in a number of developed countries. The objective of this study is to develop safer and affordable plant-derived biopesticides for control of bee pests and diseases from African biodiversity that have potential for use by rural farmers and beekeepers in Africa when the need arises. In the previous project period, 50 plants were selected for evaluation based on previous research work, literature information, indigenous knowledge and practices, observation and availability. Of particular interest were plants that showed visual signs of resistance to pest damage, attraction to bees and release of volatile compounds. Aerial parts from a total of 22 plants were collected and extracted, and 14 extracts were evaluated for efficacy against Varroa destructor. Two plants, icipe-BH-01 and icipe-BH-02 showed the highest potential for practical application in development of products for bee pest control. In preliminary evaluations, both icipe-BH-01 and icipe-BH-02 were toxic to varroa mites but non-toxic to bees at relatively higher doses. In the current project period, further work was undertaken to confirm the efficacy and safety of the two plant extracts and to formulate, and validate a final product.