RESUMO
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.
Assuntos
Chrysanthemum/química , Extratos Vegetais/farmacologia , Solanum lycopersicum/parasitologia , Spodoptera/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Flores/química , Hormônios Juvenis , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Metamorfose Biológica/efeitos dos fármacos , Metamorfose Biológica/fisiologia , Controle Biológico de Vetores , Spodoptera/crescimento & desenvolvimento , TunísiaRESUMO
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.
