Chalkbrood causative agent?

• A. Nosema apis
• B. Acarapis woodi
• C. Varroa destructor
• D. Ascosphaera apis

Answer: (D)

Chalkbrood is caused by a fungus, Ascosphaera apis. It specifically targets developing bee larvae in brood cells; when a larva ingests the fungal spores, the fungus grows in the gut and kills the larva, leaving behind white, chalk-like mummies inside the cell. This chalky appearance is the hallmark of the disease and is most common in cool, humid spring conditions when colonies are stressed or crowded. Management centers on reducing moisture and humidity in the hive, removing and discarding infected brood, improving ventilation, and sometimes replacing comb or requeening to lower stress.

Other common honey bee threats work differently: Nosema apis is a microsporidian that infects adult bee guts, causing dysentery and reduced performance rather than chalky brood mummies; Acarapis woodi is a tracheal mite that affects the bees’ breathing tubes, not brood cells; Varroa destructor is a parasitic mite that weakens bees and spreads viruses, also not the cause of chalk-like brood infections.