Seasonal Incidence and Management of European Foulbrood Diseases in Apis mellifera L. Colonies of Kangra Valley of Himachal Pradesh, India

Abstract

The introduction of the European honey bee (Apis mellifera) into Asia has contributed to the spread of various pathogens, including Acarapis woodi, European foulbrood (EFB), and Sac brood. The study aims to seasonal incidence and management of European foulbrood diseases in Apis mellifera L. Colonies of Kangra Valley of Himachal Pradesh. The present study, conducted from July 2024 to June 2025 in both the stationary apiaries of Kangra Valley (Himachal Pradesh) and migratory regions of Anupgarh (Rajasthan), aimed to assess the seasonal incidence and management of European foul brood (EFB) in Apis mellifera colonies. Seasonal observations indicated significant fluctuations in colony strength, brood area, pollen stores, and honey reserves, with optimal colony performance occurring between April and August. The incidence of European foul brood ranged from 1.00% to 48.00% in stationary colonies and from 2.40% to 40.00% under migratory conditions. A positive, though statistically non-significant, correlation was observed between EFB incidence and environmental factors such as minimum temperature, rainfall, and relative humidity, as well as internal hive parameters like brood area. Field-level management trials were conducted to evaluate eco-friendly control strategies for EFB. Among the treatments tested, the fungal extract Agaricus bisporus at a concentration of 3 ml per 250 ml sugar solution proved most effective, achieving a reduction of up to 75.38% in EFB infestation. Other notable treatments included Agaricus bisporus (1.0 ml/250 ml sugar solution), Phyllanthus emblica, the shook swarm method, and Ficus religiosa, which recorded reductions of 57.88%, 46.78%, 35.07%, and 28.45% respectively. In contrast, Melia azedarach and Azadirachta indica were the least effective, with only 12.65% and 20.46% reduction in EFB incidence, respectively. Among various treatments tested, Agaricus bisporus extract at a concentration of 3 ml per 250 ml of 50% sugar solution was the most effective, reducing EFB infestation by up to 75.38%. Lower concentrations also showed considerable efficacy. Additionally, clove oil and Ocimum basilicum extracts were effective in reducing EFB infestation.