An extensive survey was conducted in Coimbatore and Dharmapuri districts of Tamil Nadu from June, 2017 to May, 2018 to determine the species diversity and relative abundance of fruit flies in gourds viz., snake gourd (Trichosanthes anguina L.), ridge gourd (Luffa acutangula L.) and bitter gourd (Momardica charantia L.). The maximum species diversity of fruit flies was 0.15, recorded in Coimbatore in snake gourd. Bactrocera cucurbitae (Coquillet) (Diptera: Tephritidae) being predominant species (>95%) in both Dharmapuri and Coimbatore followed by Dacus ciliatus (Loew) (5%). The relative abundance of B. cucurbitae was high in all the three gourds at both locations. The diversity index, richness and evenness index were computed for both locations and it has concluded that fruit fly diversity was high in Coimbatore (0.06, 0.15 and 0.21, respectively) compared to Dharmapuri. Results of the present investigation may be utilized in developing a sustainable fruit fly management strategy in cucurbitaceous vegetable ecosystem.
Key words : B. cucurbitae, D. ciliatus, Methyl eugenol, Cue lure, Diversity indices, Relative abundance