Toxic effects of neem products (Azadirachta indica A. Juss) on Aedes aegypti Linnaeus 1762 larvae

Abstract

Treatment and comparative analysis of the properties of aqueous extracts of seed kernel of Azadirachta indica A. Juss (neem) was carried out on Aedes aegypti larvae. The aim of this work was to evaluate lethal effects of neem products (1% Suneem, formulated neem oil and neem powder) on A. aegypti larvae. Assays showed that A. indica was toxic to larvae of A. aegypti. For 1% Suneem, 1% formulated neem oil and neem powder, the lethal concentrations and lethal time at 50% (LC 50 and LT 50 ) for A. aegypti were 2 and 8 mg/l after 24 h and 3 mg/l after 120 h, respectively. Assays showed that Suneem and Formulated neem oil were more toxic to A. aegypti than Neem powder. Both products of the neem (A. indica, A. juss) have a remarkable influence on the development of A. aegypti larvae, causing an inhibition of nymphs and adults emergency. The Histopathological results revealed a serious damage on the epithelial columnar cells, a perturbation of alimentary flow, slightly hypertrophied cells, a beginning of vacuolisation on apical level, and a bursting of some cells in posterior part of the gut. However, nuclei, adipose tissue and muscles seem to keep normal appearance.

Effects of Achyranthes aspera Extracts on the Survival and Midgut Histo-architecture of Aedes aegypti L. Early IV Instars

“…These histopathological effects of the hexane extract of leaf and stem of A. aspera on the midgut architecture of Ae. aegypti were in agreement with the earlier reports of Gusmão et al [11], Pavananundt et al [32], Costa et al [10], Abed et al [34], Ndione et al [35] who also observed similar changes in mosquito larvae on exposure to different plant extracts. Hamouda et al [36] observed vacuolated epithelial layer, enflamed cells, the presence of cellular material masses in the lumen leading to loss of normal appearance of the midgut epithelium of Cx.…”

“…The histopathological effects of neem products on the larvae of Ae. aegypti showed serious damages of the columnar epithelial cells, perturbation of alimentary flow in the alimentary canal, slight hypertrophy of some cells, vacuolization degeneration and extensive lysis of some cells [35]. tested the impact of fixed oil and crude extract from sa-dao-thiam, Azadirachta excels (Jack) seed kernel against Ae.…”

Larvicidal Activity and Histopathological Effect of Averrhoa bilimbi Fruit Extract on Aedes aegypti from Surabaya, Indonesia

“…And this is in accordance with [12] who explained that acceleration of diffusion occurred based on difference of concentrations of dissolved materials during the process. The higher the difference of concentration, then the faster diffusion will occur, resulting in higher stress to the larvae.…”

Toxicity of aristolochic acids isolated from Aristolochia indica Linn (Aristolochiaceae) against the malarial vector Anopheles stephensi Liston (Diptera: Culicidae)

“…The Lethal concentration (LC 50 11 and LC 90 ) was calculated using probit analysis (Finney, 1979). The treated (Aristolochia acids I and II -1000ppm) and control larvae were fixed in 4% 15 formaldehyde for 2 h at 4  C according to the established method of (Raymond, 2007) with slight 16 modifications. The dehydration of tissue was made sequentially with alcohol viz., 50, 60, 70, 80, 90 17 and 100% for every two hours.…”