Current developments in Ascosphaera apis (Maasen ex Claussen) L. S. Olive & Spiltoir: The causative agent of chalkbrood disease in honeybees (Hymenoptera: Apidae)

Chalkbrood is an invasive mycosis in honeybees caused by Ascosphaera apis (Maasen ex Claussen) L. S. Olive & Spiltoir, that exclusively affects honeybee brood. The disease causes about 5 - 37% reduction in honey production in the world and 80% brood death. The severity of the disease, these days, has increased pesticide use and frequent long-distance transportation of colonies which may have provided an additional opportunity for A. apis infection. Furthermore, the fact that A. apis is so widespread in the globe and its viable spores can be found in stored honey, pollen, pollen capsules/ tablets, used hive components, used beekeeping tools and equipments, and possibly in soil around infected apiaries for more than 15 years, makes the possibility of its eradication most unlikely. Even though management strategies, chemicals and the use of selected chalkbrood resistant bees have all been shown to have some benefits so far, safe control of the disease have been noticed to be difficult. Thus, genetic engineering works for better manipulation of the fungus, molecular investigation of pathogenesis pathways of A. apis, and possible identification of strategies to break the pathway through the identification of responsible genes for its pathogenesis shall take current issue of research for better understanding of chalkbrood.