Azadirachtin-Induced Sterilization in Mature Females of Rhodnius prolixus
نویسندگان
چکیده
The effects of azadiraehtin A , given oral ly, on the reproduct ion of mature females of Rhodnius prolixus were studied. Azadiraeht in A caused a reduction in oocyte growth and consequently in the egg product ion in a dose-dependent manner. Eggs layed had no alteration in their viabil it ies. A significant correlat ion between these effects and the titers of both vi tel logenin in the haemolymph and vi tel l in in the ovaries was observed. Ecdysteroid titers in haemolymph and ovaries, as determined by radioimmunoassay, were decreased by this treatment. In vitro analysis suggested that azadiraehtin may directly interfere in ovarian ecdysteroid product ion. The significance of these findings in relat ion to the mode of action of azadiraehtin is discussed.
منابع مشابه
Chagas' disease and its insect vector. Effect of azadirachtin A on the interaction of a triatomine host (Rhodnius prolixus) and its parasite (Trypanosoma cruzi).
The ED50 for moulting inhibition by injected azadirachtin A is for fourth instar larvae of all the triatomines, Triatoma vitticepes, T. pseudomaculata, T. maculata, T. brasiliensis, T. lecticularis, T. matogrossensis, T. infestans, Rhodnius prolixus. R. neglectus, R. robustus, Panstrongylus megistus, and P. herrera in the range of 10-25 ng/larva. In Rhodnius prolixus, the survival of T. cruzi w...
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The antifeedant and antimolting effects of azadirachtins A and B, and of a synthetic derivative, 7-acetyl-azadirachtin A were examined. Given through a blood meal, the effective dose (ED50) for the antifeedant effect ranged from 25 to 30 ng/ml of blood for the three compounds. ATP, a phagostimulant, also given orally, reversed the antifeedant action of azadirachtin A. The ED50 values for molt i...
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The response to intra- and interspecific faecal assembling signals was tested in Rhodnius prolixus. Papers impregnated with excrement of R. prolixus induced the aggregation of larvae of this species, but also of those of Triatoma infestans. However, faeces belonging to T. infestans were not able to assemble larvae of R. prolixus. On the other hand, there was no response of R. prolixus to putati...
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