STUDIES ON MORPHOLOGY OF FRUIT FLIES (DIPTERA: TEPHRITIDAE) AND INFLUENCE OF ABIOTIC FACTORS ON THE POPULATION OF FRUIT FLIES IN CUCURBIT ECOSYSTEM.

Fruit flies (Diptera: Tephritidae) are important quarantine pests that may cause even up to 100 per cent yield losses in cucurbits. Among them, Zeugodacus cucurbitae (Coquillett) and Dacus ciliatus Loew are the serious pests of cucurbits. Survey was conducted in Coimbatore (11°14'60.00"N; 77°18'60.00"E) and Dharmapuri (40°26.767'N; 79°58.933'W) districts of Tamil Nadu, India, during 2017-2018, in the fields of snake gourd, ridge gourd and bitter gourd. Approximately 10 infested fruits from each vegetable ecosystem were collected and placed in glass cages for 15-20 days. Emerged flies were identified by using the taxonomical keys and confirmed through molecular characterization. The overlapping abdominal tergites are the key character to distinguish the Bactrocera genus from Dacus. Further, the presence of median vittae, r-m cross vein on forewing pecten on the male's abdomen and black facets on the face are the identification characters for Z. cucurbitae. Whereas, D. ciliatus with two facial spots. The amplicon size of collected fruit flies was found to be 480 bp. The population of both Z. cucurbitae and D. ciliatus showed a significantly positive correlation with rainfall and relative humidity. Whereas, it was negative with respect to maximum temperature and sunshine hours in both the locations. [ABSTRACT FROM AUTHOR]