The effect of some essential oils taken from Cinnamomum zeylanicum, Citrus
limonum and Rosmarinus Officinalis was investigated in relation to the growth of bacteria
Paenibacillus larvae which causes American Foulbrood disease that affects world hon
ey
bees Apis mellifera L. The study was carried out in the laboratories of the Faculty of
Agriculture, Damascus University from 2012 till 2013. This is in order to contribute to
preparing an integrated pest management program for American Foulbrood disease. The
oils were extracted from the plants using steam distillation. The effects of the
concentrations of oils on the growth of P. larvae were tested between (3.90625 - 500
μg/ml) using agar disc diffusion in petri plates. Results showed that the essential oils used
stop the growth of P. larvae in some of their concentrations. The minimal inhibitory
concentrations which stop the growth of P. larvae of the oils of Cinnamomum zeylanicum,
Citrus limonum and Rosmarinus officinalis were recorded at 31.25 μg/ml, 62.5 μg/ml, 125
μg/ml respectively.
