Bacterial diversity in the honey sac during bee foraging on winter-flowering flora and dominant Bacillus subtilis inhibits Hafnia alvei

<i>B. subtilis</i> was identified in all sample sources, indicating the potential importance of <i>B. subtilis</i> as a probiotic in the bee gut for honey production, and <i>B. subtilis</i> could promote the disease resistance and health of honeybees in winter.