Résumé:
The realization of this thesis allowed us to collect information on an ecological study of the
devastating species of crops in general and especially of the cereal crops. This is materialized by
the determination of two species belonging to the order Coleoptera and the family Scarabaeidae.
These are Pseudoapterogyna tusculus Buquet and Pseudoapterogyna dispar Buquet.However, a
systematic analysis of the larvae of Rhizotrogini allowed us to establish a recency of the forms of
the anal shield (Raster). This will allow agricultural systematicians and technicians to determine
the Rhizotrogini species based on the shape of the raster. The use of thin-layer chromatography
and mass spectrophotometry enabled us to carry out a phytochemical study in which five
flavonoid molecules (Quercitine Kaempherol Luteoline, Apigenin and Quercetin 3OR in Nerium
oleander Plant of the family Apocynaceae. The effects of phytocoants of this plant are expressed
by the hydrological extract of the Neruim balsam leaves which are toxic to the larvae of
Rhizotrogyni (Coleoptéra Scarabaeidae). This toxicity is expressed by the inhibition of the AchE
and the variation of the Protein level.
