| Summary: | The essential oils extracted from leaves of the Southern
Brazilian native species Drimys angustifolia Miers
(DA) and Drimys brasiliensis Miers (DB) by Clevenger
distillation were analyzed by gas chromatography/
mass spectrometry (GC/MS). The oils of DA and
DB consisted predominantly of monoterpenoids and
sesquiterpenoids. The largest components of DA oil
were bicyclogermacrene (19.6%), sabinene (9.7%)
and myrcene (5.2%), while DB oil was characterized
by cyclocolorenone (18.2%), followed by terpinen-4-
ol (8.7%) and alpha-gurjunene (6.9%). Laboratory
tests were carried out to determine the repellency of
the essential oils to the drywood termite Cryptotermes
brevis (Isoptera: Kalotermitidae). It was observed that
the oil showed repellency at the concentrations 25, 12.5,
and 6.25 μg/mL. The oils of both species exhibited a
negative repellency index, which represents repellent
activity, except for DA oil at the highest concentration,
which was attractive. Five deaths (11% of the termite
sample) were observed at 25 μg/mL DA, in the fourhour
repellency test, while four deaths occurred at 12.5
μg/mL (approximately 9%). The essential oil of DB did
not cause any termite deaths.
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