Disruptive effects of pomegranate Punica granatum Linn. (Lythraceae) extracts on the reproductive potential of desert locust Schistocerca gregaria (Forskal) (Orthoptera: Acrididae)

The present study aims to investigate the disruptive effects of ethanol, petroleum ether and n-butanol extracts from the fruit peel of Punica granatum on the reproductive potential of Schistocerca gregaria. After treatment of penultimate or last instar nymphs, a predominant inhibitory effect of all extracts on the number of egg pods/♀ was exhibited. Remarkably decreased number of eggs/pod was caused by ethanol extract at the highest concentration level (40.0%) and n-butanol extract at the higher three concentration levels (40.0, 20.0 and 10.0%). The adult females had been enforced to lay eggs in a slow rate, regardless the extract, concentration level or the time of treatment. Treatment of penultimate instar nymphs with ethanol extract or petroleum ether extract led to slightly reduced fecundity while n-butanol extract caused a drastic reduction in fecundity, especially at the higher three concentration levels. After treatment of last instar nymphs, slightly reduced fecundity was generally recorded but remarkably reduced fecundity was caused at the highest concentration level. A prevalent suppressing effect on the fertility was explored after treatment of penultimate instar nymphs with all extracts. Detrimentally impaired fertility was observed after treatment with ethanol extract or petroleum ether extract. Moreover, unexceptionally deranged fertility was recorded after treatment of last instar nymphs, irrespective of the extract. The embryonic developmental rate had been generally subjected to an extended inhibitory effect since the incubation period was slightly or substantially prolonged, regardless the time of treatment. Keywords: ethanol, petroleum ether, n-butanol, oviposition fecundity, fertility, embryonic development.