Insecticidal activity of Peganum harmala seed extract against the diamondback moth, Plutella xylostella

摘要

The diamondback moth, Plutella xylostella (L.) (Lepidoptera Plutellidae) is a key pest in cruciferous plants. Ethanol extract of Peganum harmala L. (seed) have shown pronounced effect on larval mortality, larval and pupal weight, oviposition deterrence, percent pupation, egg hatching and adult emergence of the diamondback moth, P. xylostella. A mortality of 66 and 100% was found in the third instar larvae that had fed for two days on the cabbage leaves treated with the ethanol extract at concentrations of 30 and 40 mg/ml, respectively. Significant dose response was observed on larval and pupal weight; pupal and adult emergence rate. Significant differences were also observed on oviposition. Percentage of egg hatching was reduced significantly in 30 and 40 mg/ml but not in 10 and 20 mg/ml concentrations. Obtained results showed that ethanol extract of P. harmala had a good insecticidal activity on P. xylostella.