Application of Herbal Essential Oil Extract Mixture for Honey Bees (Apis mellifera L.) Against Nosema ceranae and Nosema apis

In recent years, interest in herbal essential oil extracts for the treatment of nosemosis has steadily increased. The great importance of this study is in evaluating and validating the synergistic effect caused by the mixture of different herbal extracts. The aim of the study was to investigate through cage experiments and field studies the effect of mixed herbal essential oil extracts and to determine the most suitable application methods and doses of the product in the treatment of nosemosis. The duration of the experiments was three weeks. Results show that the herbal essential oil extract mixture (HEOEM) is effective on both Nosema apis and Nosema ceranae, and on the two together (mixed infection). With respect to application methods, the results revealed that the most suitable method is spraying HEOEM with sterilized distilled water on adult bees and on both sides of frames; 500 µL per cage and 2,000 µL per frame were found to be effective doses of HEOEM in the experimental cages and hives. HEOEM can be a viable alternative to synthetic products in the immediate future as the contents are natural and have no toxic effect on honey bees.