Bioactivities of seven chrysanthemum species flowers powder on Spodoptera littoralis (Boiduval) larvae.

We have screened seven Chrysanthemum species, collected from different biotope in Tunisia for the antifeeding and growth regulatory activity against S. littoralis (Lepidoptera: Noctuidae) an insect pest of tomato. The flowers powder was added to the Poitout and Bues (1974) artificial diet at three concentrations: 4, 8, and 16%. After ten days of treatment, the consumed quantity determination revelled that these species have an antifeeding activity proportional to the concentration, more considerable for the C. fuscatum and C. Myconis flowers powder. At the concentration of 16% the larvae weight was significantly delayed in the average time to the control, these results were compared to the effect of Cestrum parquii on S. littoralis and Pieris brassicae The moulting date determination showed an elongation of the third, fourth and fifth stages at the high concentration probably due to the presence of juvenile hormones Analogues.

A study on the potential role of Trichomonas vaginalis in transmission of Herpes simplex virus type II.

Some strains of Trichomonas vaginalis have been reported to contain virus-like particles (VLP). Whether they were natural inhabitants or acquired from the host, the emerging question will be about the potential role of this protozoan in viral transmission. The present model have been established for studying the ability of T. vaginalis to acquire Herpes simplex virus type II (HSV). Green monkey kidney cells (Vero cells) were infected with HCV and T. vaginalis was inoculated 3 days later. The progress of virus transmission was monitored by transmission electron microscopy (TEM). Fragments of virus containing Vero cells were engulfed by the trichomonads and internalised in vacuoles followed by resolution of the vacuole boundary and viral particles aggregates were retained. Viable HSV was recovered from the trichomonads for 5 days. A conducting study was done through cytopathological examination of 170 cervicovaginal smears revealed 25.8% having trichomoniasis, 2.9% HSV infection and 1.17% with combined infection, while HSV infections represent 4.5% in those having trichomoniasis. These results suggest the potential role of T. vaginalis in viral transmission to reduce this risk, further studies are recommended.

[Effect of olive leaves (Olea europea) feeding on the in vitro JH III biosynthesis by the corpora allata in Schistocerca gregaria during vitellogenesis]. / Action d'une alimentation à base de feuilles d'olivier (Olea europea) sur la biosynthèse in vitro de la JH III par les corpora allata chez Schistocerca gregaria au cours de la vitellogenèse.

Per os administration of olive leaves (Olea europea) to females of Schistocerca gregaria results in stopping vitellogenesis. These vitellogenins are not synthesised 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.