Purpose: To investigate the chemical composition and toxicity of the essential oil of
Glycosmis parviflora
(Sims) Little aerial parts against root-knot nematode and two grain storage insects (maize
weevil and red flour beetle).
Methods: Steam distillation of
G. parviflora was carried out using Clavenger apparatus in order to
extract its volatile oil. Gas chromatography/mass spectrometric (GC/MS) analysis (HP-5MS column) of
the essential oil was performed and the toxicity of the oil determined by contact test.
Results: A total of 37 components comprising 98.7 % of the essential oil were identified, of which (Z)-
caryophyllene (20.6 %), methyl isoeugenol (11.1 %), (Z)-β-ocimene (8.9 %), α-cubebene (6.4 %),
nerolidol (5.4 %), aromandendrene (4.9 %) and γ-pyronene (4.7 %) were found to be the major
components. The essential oil possessed strong nematicidal activity against
M. incognita with an LC
50
value of 92.84 μg/ml. The essential oil of
G. parviflora exhibited strong contact toxicity against
S.
zeamais and
T. castaneum adults with LD
50 values of 41.7 and 22.6 μg/adult, respectively.
Conclusion: The study indicates that the essential oil of
G. parviflora aerial parts has a potential for
development into a natural insecticide/nematicide for control of nematodes and grain storage insects.
