Journal of Mosquito Research 2015, Vol.5, No.10, 1-7
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Table 2 Mortality percent of 3
rd
instar larvae of
Culex quinquefasciatus
exposed to different concentrations of different solvent root
extracts of
Annona reticulata
(Mean mortality percent ±Standard error)
Solvent extracts
Instar
Concentrations (ppm)
Mortality % at different exposure Periods
24 h
48 h
72 h
Petroleum ether
3
rd
1
00.00±00.00
43.33±3.33
46.67±3.33
2
00.00±00.00
53.33±3.33
56.67±3.33
4
13.33±3.33
70.00±5.77
96.67±3.33
8
33.33±3.33
86.67±6.67
100.00±00.00
Hexane
3
rd
1
00.00±00.00
26.67±3.33
40.00±00.00
2
00.00±00.00
50.00±5.77
53.33±3.33
4
16.67±3.33
70.00±5.77
93.33±3.33
8
36.67±3.33
83.33±3.33
100.00±00.00
Ethyl acetate
3
rd
1
56.67±3.33
80.00±00.00
86.66±3.33
2
83.33±3.33
100.00±00.00
100.00±00.00
4
93.33±3.33
100.00±00.00
100.00±00.00
8
100.00±00.00
100.00±00.00
100.00±00.00
organisms after application of ethyl acetate root
extract at LC
50
values of 3
rd
instar larvae after 24 h of
exposure. Preliminary phytochemical analyses showed
the presence of alkaloids, steroids, terpenoids,
flavanoids, anthraquinones, tannins and phenols but
absence of saponins. The larvicidal activity was found
statistacally significance (p < 0.05) through completely
randomised ANOVA analysis (Table 7).
Table 3 LC
50
and LC
90
values (95% confidence level) of Petroleum
ether, Hexane, and Ethyl acetate solvent root extracts of
Annona
reticulata
through Log Probit analyses against 3
rd
larval instar
of
Culex quinquefasciatus
2 Discussion
Many researchers worked with different plant
extracts to unfold their larvicidal activities on different
mosquitoes species and to find out the active chemical
compound (s) involved in larvicidal activity present in
different extracts of different plants. Present study is
unique one as 100% mortality were observed with root
extracts of
A. reticulata
at very low concentrations.
Many authors reported the larvicidal activity of different
solvent root extracts of many plant parts. Some
authors also reported the larvicidal efficacy of ethyl
acetate extracts of many plant parts. Ilahi and Ullah,
2013 reported the larvicidal activity of different parts
of
Artemisia vulgaris
Linn. against 3
rd
and 4
th
instar
larvae of
Cx. quinquefasciatus
upto 24 h of exposure
period
and LC
50
values of methanol extracts of root,
stem, and leaf were 9141.0, 2224.2, and 803.2 ppm
respectively. Jayaraman et al., 2015 reported the
larvicidal activity of hexane, chloroform, ethyl
acetate, acetone, and methanol extracts of seven
aromatic plants against
Cx. quinquefasciatus, Aedes
aegypti, and Anophelis stephensi.
The ethyl acetate
extract of
Chloroxylon swetenia
showed remarkable
larvicidal activity against three mosquito species, of
which LC
50
and LC
90
values of
Cx. quinquefasciatus
were194.22 and 458.83 ppm after 12 h of exposure
period. Nganjiwa et al., 2015 worked with ethanolic
leaf and root extracts of
Balanites aegyptica,
Calotropis procera, and Eucalyptus globulus
against
4
th
instar larvae of mosquito species upto 24 h of
exposure period. At 10 ppm concentration ethanolic
root extracts of
Balanites aegyptica, Calotropis
procera, and Eucalyptus globulus
showed 64.67,
73.67, and 65.00% mortality having LC
50
values 7.24,
6.61, and 6.92 ppm respectively. Rawani et al., 2010
reported the larvicidal activity of leaf ethyl acetate
extract of
Solanum nigram
and showed 100%
mortality at 50 ppm concentration with LC
50
value17.04
ppm after 24 h of exposure. So comparing the result
Solvent extracts Period of
exposure (h)
LC
50
(ppm) LC
90
(ppm)
Petroleum ether 24
10.499
27.098
48
1.5052
12.6293
72
1.2712
3.5133
Hexane
24
9.7022
25.1332
48
2.1187
11.2455
72
1.5053
4.1251
Ethyl acetate
24
0.9191
2.8133
48
0.5397
1.3747
72
0.3656
1.1339
