Potential of biologically active plant oils to control mosquito larvae (Culex pipiens, Diptera: Culicidae) from an egyptian locality

Abstract

SUMMARYThe insecticidal effect of six commercially available plant oils was tested against 4 th larval instars of Culex pipiens. Larvae were originally collected from Meit El-Attar, Qalyubia Governorate, Egypt, and then reared in the laboratory until F 1 generation. The LC50 values were 32. 42, 47.17, 71.37, 83.36, 86.06, and 152.94 ppm for fenugreek (Trigonella foenum-grecum), earth almond (Cyperus esculentus), mustard (Brassica compestris), olibanum (Boswellia serrata), rocket (Eruca sativa), and parsley (Carum ptroselinum), respectively. The tested oils altered some biological aspects of C. pipiens, for instance, developmental periods, pupation rates, and adult emergences. The lowest concentrations of olibanum and fenugreek oils caused remarkable prolongation of larval and pupal durations. Data also showed that the increase of concentrations was directly proportional to reduction in pupation rates and adult emergences. Remarkable decrease in pupation rate was achieved by mustard oil at 1000 ppm. Adult emergence was suppressed by earth almond and fenugreek oils at 25 ppm. In addition, the tested plant oils exhibited various morphological abnormalities on larvae, pupae, and adult stages. Consequently, fenugreek was the most potent oil and the major cause of malformation of both larval and pupal stages. Potency of the applied plant oils provided an excellent potential for controlling C. pipiens.

The insecticidal activity of four medicinal plants against the blowfly Lucilia sericata (Diptera: Calliphoridae)

“…The abnormalities could be attributed to the metamorphosis‐inhibiting effect of plant oils, as a result of the disturbance of hormonal control, suggesting a type of insect growth‐regulating activity 20–24 …”

“…Botanical insecticides are relatively harmless to nontarget organisms, including humans, and are also biodegradable and harmless to the environment 19 . Medicinal and herbaceous plants have been used to control insects 19–25 . Some plant extracts have been shown to be effective in controlling L. sericata 20,26,27 .…”

“…Some plant extracts have been shown to be effective in controlling L. sericata 20,26,27 . In addition, the applied oils fenugreek, 24,28 mustard, 15,24,29 and celery 30,31 show an insecticidal effect on certain insects of medical and veterinary importance.…”

Larvicidal Efficacy of Different Plant Parts of Railway Creeper, Ipomoea cairica Extract Against Dengue Vector Mosquitoes, Aedes albopictus (Diptera: Culicidae) and Aedes aegypti (Diptera: Culicidae)

“…In present study, larvae exposed to I. cairica extract showed darkening or blackening of abdomen and twisted abdomen. Comparable abnormalities were reported by Khater and Shalaby (2008) when larvae of Culex pipiens showed abnormalities such as pigmented and twisted larvae after exposure to some commercially available plant oils. …”

Ecosmart Biorational Insecticides: Alternative Insect Control Strategies

“…Valuable appraisals about the mode of action are those of Price & Berry (2006), Isman (2006Isman ( , 2010; Tripathi et al (2009);and Dubey (2011). Some essential oils have larvicidal effect and the capacity to delayed development and suppress adults emergences and induce abnormalities during development of insects of medical and veterinary importance, Fig (1-5) (Khater, 2003;Shalaby & Khater, 2005;Khater & Shalaby, 2008;Khater et al, , 2011.…”