Journal of Mosquito Research 2015, Vol.5, No.15, 1-15
10
Table 5: Activity of Est-A, Est-B, G6PD, AcPH and APH in different populations of
Aedes aegypti
Populations
Est-A
(µM of a-napthol
produced/mg of
protein/min)
Est-B
(µM of b-napthol
produced/mg of
protein/min)
G6PD
(µM of NADP
reduced/mg of
protein/min)
AcPH
(µg/individual)
APH
(µg/individual)
Urban Area
Mean±SD
Mean±SD
Mean±SD
Mean±SD
Mean±SD
VHN
0.1497±0.0703
0.2523±0.0658
0.1204 ±0.1219
0.0593 ±0.0137
0.1583 ±0.0192
CPM
0.3572±0.0579
0.2744±0.0628
0.1702 ±0.0273
0.0365 ±0.0210
0.0307 ±0.0105
JPN
0.3426±0.1091
0.2277±0.0256
0.1907 ±0.0121
0.0229 ±0.0096
0.0287 ±0.0190
AGN
0.2431±0.1018
0.22150±08035
0.1452 ±0.0201
0.0225 ±0.0110
0.0295 ±0.0123
KPR
0.1322±0.0451
0.2100±0.0678
0.1556 ±0.0165
0.0332 ±0.0126
0.0236 ±0.0155
Rural Area
Mean±SD
Mean±SD
Mean±SD
Mean±SD
Mean±SD
NJD
0.5285±0.0598
0.3129±0.0425
0.1487 ±0.1092
0.0898 ±0.0155
0.1885 ±0.0157
HSR
0.4387±O.1017
0.2967±0.0725
0.2211 ±0.0224
0.0478 ±0.0199
0.0881 ±0.0206
CRP
0.5632±0.1041
0.3499±0.2582
0.3622 ±0.0119
0.0565 ±0.0106
0.0995 ±0.0119
MDA
0.4569±0.1304
0.2976±0.0803
0.3210 ±0.0221
0.0478 ±0.0119
0.1015 ±0.0229
Legend: VHN- Vishweshwara nagar, CPM- Chamundipuram, JPN- J.P. Nagar, AGN- Agrahara, KPR- Kuvempunagar, NJD-
Nanjangud, HSR- Hunsur, CRP- Channarayapatna, MDA- Mandya. n = 30
the implementation of a control program. Laboratory
bioassays are convenient for evaluating the efficacy of
chemicals on disease transmitting vectors.
Insecticide susceptibility test is one of the most
important aspects to be monitored in public health
programs related to vector control. The variation in
the susceptibility levels will depend on the breeding
habitat, genetic constitution of the mosquito species
and the general ecology of the area (Shililu et al.,
2003). Thus the larvicidal efficacy of insecticides will
vary from place to place and from species to species.
Such studies will give us an insight in to the
susceptibility status of the local vectors, which will be
of immense help in planning out an effective control
strategy. Bioassay on
Aedes
species gathers more
importance in the current situation as there has been
widespread epidemic of Dengue and Chikungunya in
Karnataka and many other states (Ravi, 2006).
Bioassay results on this species are available from
other places also especially in populations of
Ae.
aegypti
larvae form rural areas of Maharashtra state,
India and found that, Deltamethrin was more effective
than organochlorine and organophosphate tested
(Chakraborti et al., 1993). Difference in the LC
50
values between the populations of
Ae. aegypti
was
noticed for the insecticides; temephos, malathion and
permethrin in Thailand (Ponlawat
et al.
,
2005). And in
line with the present study, it was found that
Ae. aegypti
more resistant/tolerant in rural population. Similarly,
susceptibility tests were also carried out on
Ae.
aegypti
populations against temephos insecticide in
Federal District, Brazil (Carvalho, 2004) and found
differences in mortality between the populations tested.
Deltamethrin was found to be superior to
lambdacyhalothrin and cyfluthrin against
Ae. aegypti
,
Anopheles
stephensi
and
Culex
quinquefasciatus
at
Delhi (Ansari et al., 1998), which supports the present
investigation.
Perusal of the present result indicates that the rural
population was found to possess relatively more
tolerance against the pyrethroid - deltamethrin tested
(Table 1). There have been outbreaks of chikungunya
and dengue in Karnataka along with other states. Such
epidemics are eye-opener to intensify vector control
especially in the rural areas. As far as insecticide
resistance mechanisms are concerned in Malaysia, a
considerable amount of research indicated that
Malaysian mosquitoes have demonstrated variable
biochemical mechanisms in resistance to various
insecticide classes (Wan et al., 2013). It is in this
regard the present study in Karnataka, have gained
importance. The scrutiny of the overall results of the
bioassay reveals that, the populations of the species
may show much variation for which their ecology will
also play a major role. In order to classify the genetic
differences (responsible for insecticide tolerance) if
any, between the populations from urban and rural
