Basic HTML Version
Journal of Mosquito Research, 2013, Vol.3, No.11, 76-81
ISSN 1927-646X
http://jmr.sophiapublisher.com
79
Table 5 Result of qualitative phytochemical analysis of the crude
extract of the tested plant
Phytochemicals
Absent/ Present
Tannin
Absent
Saponin
Present
Flavonoid
Absent
Alkaloid
Present
Steroid
Absent
Cardiac glycosides
Present
Terpenoid
Absent
Free glycosides bound anthaquinones
Absent
2 Discussion
The transmission of mosquito-borne diseases can be
interrupted by the potential insecticides of herbal
origin at the individual as well as at the community
level (Campbell et al., 1993). Recently the natural
insecticides of plant origin have been given
importance due to their ecofriendly nature and
biodegradability as a substitute of synthetic
insecticides for the control of vectors of public health
importance. Different types of phytochemical of plant
either from the whole part or from the specific parts
come out with solvent during chemical extraction
depending on the polarity of the solvent (Rawani et al.,
2012; Chowdhury et al., 2007). These phytochemical
generally act as a toxicant for adult, pupa as well as
larval form of mosquitoes, while some interfere with
the growth (growth inhibitory) and reproduction
(ovicide deterrent). The present study evaluate
biocontrol efficacy of crude extract and ethyl acetate
extract of seed coat of
C. sophera
against
Cx.
quinquefasciatus
. Highest mortality was recorded in
1% concentration of crude extract against 1
st
instar
larvae. The ethyl acetate extract showed 100%
mortality at 520 ppm against 1
st
instar larvae after 24
h. The phytochemical analysis of crude extract of seed
coat of
C. sophera
indicates the presence of some
secondary metabolite which either in single form or in
combination with other responsible for larval death.
There is no any abnormal behaviour of non-target
organisms when they exposed to LC
50
value so it is
safe to use in natural condition. Some other authors
also reported the efficacy of ethyl acetate extract of
plant parts against mosquito larvae. Senthil Nathan et
al. (2008) reported the activity of ethyl acetate extract
of the leaves of
Dysoxylum malabaricum
against the
larvae of
Anopheles stephensi
. Highest mortality
occurred in 4
th
instar larvae. Matasyoh et al (2008)
reported the efficacy of the ethyl acetate extract of
leaves of
Aloe turkanensis
against
Anopheles gambiae
where 100% mortality occurred at a concentration of
0.2 mg/L with a LC
50
value of 0.11 mg/mL. The ethyl
acetate extract of leaves of
Ocimum sanctum
produced
significant mortality against
Aedes aegypti
and
Cx.
quinquefasciatus
, with LC
50
values of 425.94 ppm and
592.60 ppm, respectively (Anees, 2008). Rawani et al.
(2010) studied on the ethyl acetate solvent extract of
Solanum nigrum
showed its highest mortality (100%)
against
Culex quinquefaciatus
at 50 ppm dose having
LC
50
value 17.04 ppm after 24 h of exposure period.
In conclusion, crude and ethyl acetate extracts of
C.
sophera
can be effectively used as a potent mosquito
larvicide. Furthermore there is more investigation
necessitates to identify the active ingredient and their
mode of action and field application which become
establishes the
C. sophera
as a new insecticide in a
mosquitoes control program.
3 Material and Method
3.1 Plant material
Fresh and matured seeds of
C. sophera
were harvested
randomly during April~June, 2011, from plants
growing at the outskirts of Burdwan (2
3
°16'N,
87°54'E). Initially collected seeds were washed with
distilled water and soaked on paper towel.
3.2 Collection of larvae
Mosquito larvae of the species
Cx. quinquefasciatus
used during the present piece of work were taken from
an established mosquito colony of Mosquito Research
Unit, Department of Zoology, Burdwan University,
maintained at (27
±
1)
℃
temp and 85% RH.
3.3 Preparation of crude extracts
Seed coats were crushed with a mechanical blender
and the juice was filtered by Whatman no-1 filter
paper. The filtrate was used as stock solution (100%
concentration) for further bioassay experiment.
3.4. Preparation of solvent extracts
Dried seed coats (250 g) were put in a Soxhlet
apparatus and the plant extract was prepared using