Mosquitoes are most important group of insects, transmitting wide range of infectious agents. These are acting as vectors for numerous animal and human diseases like Bovine ephemeral fever, Filariasis, Dengue fever, Malaria, Yellow fever, Japanese encephalitis. The vector control strategies are the potent tool to minimize the risk of transmission of these infectious agents. In Pakistan, these vector control strategies mainly rely on chemical insecticides. The irrational use of these chemicals is the leading cause of emerging insecticide resistance in these mosquitoes. It has been also revealed that these conventional insecticides are not eco-friendly, has drastic effects on non-targeted biota and also having the potential of cross resistance among various compounds. To mitigate this issue, special attention is required to use natural products and plant origin as an alternate to these chemical insecticides. As these herbal plants are not eco-friendly but also having least drastic effects on non-targeted population. Cympbogon citratus (lemon grass) could have good adulticidal and larvicidal activity against mosquitoes of genus culex.
The mosquitoes of genus Culex were identified on the basis of distinguishing morphological features as described by standard published morphological key. After identification the adults of mosquitoes of genus Culex were further reared in the insectary of Department of Parasitology, UVAS, Lahore to take F1 and larval stages of mosquitoes of Culex spp. Briefly, female mosquitoes were feed on periodic blood for oviposition. These emerging L3 & L4 larvae and 2-3 days old adults were further used in protocol. The fresh green leaves of C. citratus were used in current study. After collection and identification the aqueous and methanol extract were taken by Soxhlet apparatus (Govindarajan et al., 2011). Afterwards different concentrations of these extracts were prepared to calculate the diagnostic dose of these extracts. Then the larvicidal and
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adulticidal efficacy of these extracts were evaluated by using CDC bottle bioassays as described by (WHO2005)
The LC50 and LC90 were calculated by using probit analysis. Staistical package of social sciences (SPSS), version 13.00 were used for this purpose. Duncans’s Post HOC Test were applied to compare the main mortalities among the group of different concentrations of plant extracts and control group. The results revealed that C. citratus is effective against Culex mosquitoes both as larvicidal and adulticidal.