Adverse effects of certain botanicals on some biological aspects of the peach fruit fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae)

The peach fruit fly (PFF), Bactrocera zonata (Saunders), is a serious, multivoltine and polyphagous insect pest that infests fruits directly, causing a serious damage. Increasing incidence of insecticide resistance has led to a renewed interest in developing insecticides with alternative modes of action, lower environmental impact and greater compatibility with integrated pest management (IPM) programmes. Accordingly, a selection of crude Extracts (CEs) and essential oils (EOs) of eucalyptus, jojoba, lavender, neem was screened against the PFF and their effects on some biological aspects were studied. Incubation periods of EOs at the used concentrations were lower than that of CEs. The egg hatchability in case of CEs was significantly affected compared to EOs. The average numbers of pupae collected differed significantly according to both CEs and EOs of the tested four plants. In respect of the CEs, the formed pupae of treated individuals were significantly lower than that of the untreated ones. EOs of lavender inhibit pupal formation of B. zonata more strongly than the EOs from the other tested botanicals. The average number of emerged adults of CEs- or EOs-treated larval artificial diets were highly significantly lower than that of the control. The differences between averages of emerged adults of CEs of the four tested botanicals were significant. Neem crude extract was the most potent, showing the lowest average of emerged adults of B. zonata. The differences between averages of malformed adults resulted in both CEs- and EOs-treated larval diets were statistically non-significant. Based on these results, EOs were more effective than CEs of the used plants against the PFF.