التأثيرات الفسيولوجية المثبطة للتغذية لبعض المنتجات الطبيعية على دودة اللوز الشوكية مقارنة بدودة اللوز القرنفلية

"PHYSOLOGICAL PHAGODETERRENCY EFFECTS OF CERTAIN NATURAL PRODUCTS ON THE SPINY BOLLWORM COMPARED WITH THE PINK BOLLWORM.

                                                "The effect of a new natural product, Abamectin (Vertimic), JHM Pyriproxyfen (Admiral) and extracts of two naturally rejected plants (Bestachia, Adahatoda vasica and Dumb-cane,  Definbachia picta ,on two cotton bollworms, Earias insulana(Boisd) and  Pectinophora gossypiella(Saund.) was determined.

         These compounds and extracts have a toxic action on larvae of both cotton bollworms when added to the larval artificial diet .A positive relationship between the larval mortality and the applied concentrations was found.

         The effect of treatment with the LC50 concentrations of both tested compounds and plant extracts on newly hatched larvae of both bollworms was extended to the following developmental stages, represented as morphological deformalities.

         The determined LC50of the two tested compounds and two plant extracts was tested in a field experiment on cotton plants.  

         Histopathological studies on larvae fed on diets treated with tested compounds and plant extracts showed histopathological changes in cuticle, mid-gut, muscles, fat bodies and malpighian tubules as compared with control larvae.

         Total larval protein content in treated larvae fluctuated between an increase and decrease than in control insects.

         The electrophoresis analysis using SDS-PAGE for β-esterase enzyme in the larval stage fed on diets treated with tested compounds showed clear varieties in the dense and number of bands.

  Key words:

                     Spiny bollworm, Earias insulana; pink bollworm,  

                     Pectinophora gossypiella, Abamectin (Vertimec), 

                     Pyriproxyfen (Admiral), Bestachia , Dumb-cane."