Abstract:
The study of the biological activity of crude leaf extractsPergularia tomentosa Capparis spinosa L
and L harvested northern Sahara eastern Algeria on fifth instar of Schistocerca gregaria (Forskål, 1775),
highlighted the effect of the extract on food intake, the average consumption of 0.84 g / day and 0.90 g / day for
lots fed cabbage leaves treated with the alkaloid extract of P. tomentosaandC. spinosa, respectively, and 1.22 g
/ day for lots fed cabbage leaves treated with aqueous extract of P. tomentosa and 1.51 g / day for larvae fed
cabbage treated with alkaloid extract of C. spinosa. The same goes for the other extracts, consumption is much
lower compared to individuals in the control groups.
The values of the coefficient of apparent digestive utilization (CUDA) estimated for L5 larvae of locusts fed with
cabbage leaves treated with plant extracts of P. tomontosaandC. spinosaare relatively close to those observed
in individuals with control groups. The values of coefficient of apparent digestive CUDA use among individuals
of the acetone extract are 79.44% and 83.56%P. tomentosaandC. spinosarespectively. For alkaloid extracted
P. tomentosais 83.56% for C. spinosais 84.65 and the aqueous extract is 86.04 for P. tomentosaand 85.82%
andC. spinosa. A weight loss is noted that in L5 larvae and S. gregariatreated by foliar alkaloid extract of P.
tomontosa by larvae against L5, a weight gain was observed, but at lower percentages compared to controls.
In addition, no mortality was recorded in L5 larvae, batches fed cabbage leaves treated with extracts of
C. spinosa, whereas it is observed blocking and molting by a L5 larvae fed cabbage leaves treated with the
alkaloid extract ofP. tomontosawhere a percentage mortality of 33.33% was noted.