Action d'une alimentation a base de feuilles d'olivier [olea europea] sur la biosynthesis in vitro de la JH III par les corpora allata chez shistocerca gregaria au cours de la vitellogense

Per os administration of olive leaves [Olea europea] to females of Schistocerca gregaria results in stopping vitellogenesis. These vitellogenins are not synthesized by the fat body in the heamolymph. The vitellogenin inhibition is induced by the stopping of juvenile hormone JH III by the corpora allata. These corpora allata [Medicago sp.] synthesise 10 times less JH III than those of alfalfa fed females

Similitudes immunologiques entre les substances cerebrales de schistocerca gregaria et deux neurohormones de locusta migratoria

Two neurohormones produced by two distinctive neurosecretory median cells [A [1], B] of the protocerebum have been characterized in Locusta migratoria; each with multiple functions one called neuroparsin and one stimuling the ovarian maturation called lom OMP. Using the specific immunoserum of these two neurohormones in Schistocerca gregaria, we could demonstrate the occuring of molecules related to the neuroparsin and lom OMP of Locusta. Through histology studies of the brain and corpora cardiaca complex, the immunserum revealed the presence of the two types of these neurosecretory cells suggesting the occuring in Locusta as well as Schistocerca of the same cells releasing molecules immunologically apparent to neuroparsin and lom OMP. The results were confirmed by electrophoretic separation of corpora cardiaca extract under unreduced conditions followed by a transfer on immobilon membrane

Distribution spatiale et fluctuation spatio-temporelle des principaux groupes d'insectes d'une plantation de cotonnier

The cotton entomofauna consists of various groups of Insects which schow a distribution in strata.Except the superfamily of Chalcidoidea which offers a relatively homogeneous distribution. each group of Insects studied prospect a preferential area with particular ecologic conditions. Among these conditions the trophic relation are of the first importance the Drosophilidae keep close to the organic matter in decomposition at the deep stratum. The phytophagous Insects live on the foliage at the medium strata. They could be hosts of parasites of some Chalcidoidea and Thecostomates or preys of some predators such as Empididae and Syrphidae. The interactions between these different Insects and vegetal are discussed

Characterisation des vitellogenines et des vitellines chez ceratitis capitata [diptera, trypetidae]: etude electrophoretique et immunoelectrophoretiqe

electrophoretic study of haemolymphatic proteins in Ceratitis capitata has allowed to establish a proteic sexual dimorphism in this insect. This consists in a proteic Fraction which is specific to the male and which appears at the imaginal ecdysis and stays during all the imaginal stage and in 3 other fractions which are characteristic to the female. Immuno electrophoretic study showed that these female proteins could be considered as vitellogenins the nature and the mode or incorporation of those proteins in the oocyte are discussed