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.
In this work Rosmarinus officinalis L. grown in Syria was studied. The
general characteristics of the whole plant, as well as the leaves and the flowers
were determined. It was shown that there are two varieties of Rosmarinus one
having violet flo
wers and the other having white flowers. The two varieties
were compared morphologically and they were in accord with what was
mentioned in the literature.
The two varieties were also compared chemically and it was possible to
explain the differences mentioned in the literature by differences in the
composition of the volatile oil.
The chemical study of the drug shows the quantity as well as the percentage
of its constituents. At last the main substitute of the drug used in Syria was
shown and compared with the main drug. It was shown that the composition of
the volatile oil of the substitute is different from the composition of the volatile
oil of Rosmarinus, thus it can not be used for the same purpose.
