Biocidal Activity of Some Selected Phytoextracts and Fruits of Different Citrus Cultivars against Fruit Fly Bactrocera dorsalis (Hendel) (Diptera: Tephritidae).

Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) is one of the economic pests of horticultural crops. This invasive species causes substantial economic loss to citrus produce each year in Pakistan. Farmers rely on persistent synthetic insecticides for fruit fly control. Insecticidal phytoextracts are biorational alternates to hazardous synthetic insecticides. This study evaluated the efficacy of aqueous extracts of neem (Azadirachta indica A. Juss), garlic (Allium sativum L.), ginger (Zingiber officinale Roscoe) and lime citrus (Citrus aurantifolia (Christm.) Swingle) on the fruits of five citrus cultivars (i.e. bitter orange (Citrus aurantium L.), grapefruit (Citrus paradisi Macfad), lime (Citrus aurantifolia Christm), mandarin (Citrus reticulata Blanco) and sweet orange (Citrus sinensis (L.) Osbeck) against B. dorsalis using choice and no-choice fruit-dip bioassays. Results revealed a significant reduction of pupal weight and adult emergence of B. dorsalis by 4% extracts of A. indica, A. sativum and C. aurantifolia. Moreover, a significantly higher male to female adult sex ratio was observed in case of A. indica treatment. It is concluded from overall study results that the extracts of A. indica and C. aurantifolia exhibited significant anti-insect effects on the pupal recovery, pupal weight, adult emergence and male to female ratio of B. dorsalis on all five citrus host fruits under laboratory conditions, and hence are recommended to be further evaluated under field conditions and to consider their potential incorporation in IPM programs against fruit fly infestations on citrus crop. [ABSTRACT FROM AUTHOR]