Vol. 4, Issue 4, Part A (2017)

Author(s): Mutaman AA Kehail, Nabil HH Bashir, ElNur E Abdelrahman and Awad M Abdelrahim

Abstract:
Anopheles and Culex (Diptera: Culicidae) mosquitoes are two of the major medically important pests in the Sudan. The present work objectives was to explore the larvicidal activity of local plants, viz. Nerium oleander L, Calotropis procera L. and Ricinus communis (khirwie) powders and aqueous-extracts of leaves and flowers of the first-two, and seeds of castor tested aganist 3^rd and 4^th instar larvae of A. arabiensis and C. quinquefasciatus, according to the standard methodes of WHO for rearing and assessment of mosquitoes susceptibility. Powder (3g) was suspended in 1L of tap water in a beaker (Replicate). Larvae (20/beaker) from both species were added separately to each replicate. Each treatment was replicated 3x, and the experiment was repeated twice. Mortality % was recoded after 24 hr. New set of 20 larvae was added to the same beaker every day after removing the previous group; the removal and addition was continued until 0% mortality was obtained. Regarding the aqueous-extracts, different concentrations were prepared from the tested morphological parts to determine the LD50 after 24 hr for both species. For A.arabiensis the effect of powders of Nerium leaves and flowers peresisted for 10 days with mean of 84% and 62%, respectively, while for C.quiqufasciatus the values were 10 days and 7 days, with means of 54% and 68%, respectively. Powders of Ricinus seeds peresisted for 8 days for A. arabiensis with mean 71% and for 8 days for C. quiquefasciatus, but with 58% mean.