||Ovicide and Larvicide Activities of the Essential Oils Extracted from Polyalthia longifolia and Clausena anisata on Sitotroga cerealella.
ADJALIAN Elvis ,
SESSOU PHILIPPE ,
ALITONOU GUY ALAIN ,
||OnLine Journal of Biological Sciences
||This work has objectives to study the chemical composition of
volatile extracts obtained from leaves of Polyalthia longifolia and Clausena
anisata and to evaluate their ovicide and larvicide effects by fumigation
against Sitotroga cerealella, as alternative to the pesticides of synthesis.
The analyses of the extracts by GC-MS showed that the essential oil of P.
longifolia contains 57 compounds representing 86.1% of oil and 26
compounds corresponding to 97.3% of the essential oil of C. anisata. The
main compounds identified for the extract of P. longifolia are the β-
Caryophyllene (24.5%), Allo-Aromadendrene (13.5%), the α-Zingiberene
(9.4%), the α-Humulene (8.5%) and the α-Selinene (2.6%). The extract of
C. anisata mainly composed of methyl chavicol (69.9%) is characterized by
the presence of oxygenated monoterpens (1.4%), hydrogenated
monoterpens (7.8%), hydrogenated sesquiterpens (16.2%), oxygenated
sesquiterpens (1.7%) and of aromatic compounds (69.9%). The biological
test results showed that the treatments by fumigation done with the
essential oils reduce meaningfully (p<0.001) the bursting of the ovums on
the paddy rice. The essential oil of C. anisata has completely inhibited the
viability of the larvas and the emergence of adult butterflies from the dose
0.5 μl mL−1 contrary to P. longifolia that recorded respectively
10.0±0.3% and 50.0±0.2% at the strong dose 3 μl mL−1. The study has,
otherwise, shown that the essential oils delayed the cycle of development
“ovums to adult” of S. cerealella (29.0±0.4 to 35.4±0.5 days) in relation
to the witness (25±0.1 days). The essential oil of C. anisata proved to be
more poisonous for the juvenile stages of S. cerealella. These results
provide the scientific basis for potential alternatives to the synthetic
fumigants in subsistence and commercial agriculture.
||Polyalthia longifolia, Clausena Anisata, Ovicide, Larvicide, S.
Cerealella, Fumigation, Essential Oil.
||193 - 200