Page 409 - e-Book

Genetic resistance to synthetic insecticides is a well observed phenomenon but now

resistance to biopesticides in some species like Bacillus sphaericus has also been seen (Lacy,
2007; Tabashnik, 1994). As the increase in resistance to several synthetic insecticides

generated an economic and operational difficulty worldwide due to which alternative
methods are concerned and gaining more attention (Tripathi et. al., 2002). Various species of

mosquitoes impose a serious health problem and increasing mortality both in human and live
stocks leads to the devastation of both health and economic problems in developing and

underdeveloped countries which is of great concern. The search for a new control method

mainly consists of plant-based products mostly which are non-toxic to humans, animals, have
least detrimental effect on the environment and economically sustainable. Plant-based

insecticides consist of mainly plant extracts and their active secondary metabolite products

which is also a part of integrated vector management programs (IVMP) (Elimam et. al.,
2009; Rahuman et. al., 2009).

Cinnamomum tamala has been commonly used as spices for flavours. Its leaves are used for
the isolation of essential oil called “tejpat oil”. The oil has anti-diuretic, carminative

antiflatulent activity and is also used in the treatment of cardiac disorder (Chowdhury et. al.,
2013). Leaves of Cinnamomum tamala are also used for the treatment of anorexia, dryness of

mouth, bladder disorder, diarrhea, nausea, coryza and spermatorrhea according to

“Ayurveda” (Scartezzini and Speroni, 2000). Other uses include: in the food industry for
natural food preservative and its natural aroma (Chang and Cheng, 2002). The origination of

bay leaf or tejpatti is likely from South Asia to across the globe. The leaf consists of different
secondary compounds. Due to the presence of these properties, it is widely used in medicine

and drug discovery studies (Sumono et. al., 2008).
Azadirachta indica, mostly used traditional medicinal plant. Each part of the tree (leaf, seed,

and bark) contains its own abundance of components that are accountable for different

medicinal activities. In “Ayurveda”, “Unani” and “Homeopathic” medicine Azadirachta
indica finds a prominent position due to its promisingly medicinal property. In India

Azadirachta indica is regarded as a “village dispensary” (Biswas et. al., 2002). The major

insecticidal property of the plant is due to the presence of a bioactive compound Azadirachtin
(0.1–0.3 %) which was extracted and characterized by by Morgan et al. at Keele University,

England (Schmutterer, 1985), from A. indica seeds. Azadirachtin B, salannin and nimbin are
some other bioactive ingredient which play a major role in the insecticidal activity and serve

as biopesticides. The mode of action depends upon growth disruption or dissuade feeding.
From ancient times in Ayurveda and tribal medicine, it plays a major role (Biswas et. al.,

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