Abstract:
The study on the toxicity of leaf extracts of Capparis spinosa L. (Capparidaceae) harvested
in northern Sahara's Algerian against 3
rd
instar larvae of the mosquito Culex pipiens L (Diptera,
Culicidae). It is noted that larvae of Culex pipiens treated with the aqueous extract Capparis
spinosa, a mortality rate which varies with the concentration of extract. In fact, the percentage of
the maximum mortality is reported for larvae treated with the plant extract concentrated to 100%,
75% and 50% after 24 hours of exposure. While extracts 25% and 15%, they reach the maximum
mortality rate (100%) in the fourth and fifth day. This mortality manifest differently extracts 10%,
5% and 1% reaching the maximum rate of about 96.67%, 93.33% and 53.33% respectively at the
end of 10th day. The effective concentration 50 (EC
50
) and the EC90
, estimated value for the 3
rd
instar larvae (L
3
) of Culex pipiens showed that the extract revealed interesting in terms of toxicity, it
has an EC50 and EC90 of 0.00041 mg / ml and 0.0037 mg / ml respectively. Evaluation of lethal
time 50 (LT
50) and 90 lethal time (LT
90
), shows that the extract of C. spinosa 100, 75, 50% showed
a rapid onset particular against Culex pipiens. Although these results are preliminary, they show a
good larvicidal activity of aqueous extracts of leaves of Capparis spinosa.