EFFECT OF SIX INDIGENOUS WEED EXTRACTS AGAINST CUCURBIT FRUIT FLY, BACTROCERA CUCURBITAE (COQUILETT) (DIPTERA: TEPHRITIDAE)

ABSTRACT: Effect of six different weed extracts on the repellency and oviposition deterrent were conducted against cucurbit fruit fly, B. cucurbitae (Coq.) in the laboratory of the Department of Entomology, HSTU, Dinajpur, during July to December 2021. The study was carried out primarily with 5.0 % concentration for six weed extracts followed by two weed extracts with four concentrations (0.5, 1.0, 2.0 and 4.0 %) on bitter gourd fruit. Results indicated that the tested weed extracts not only cause repellent and oviposition deterrent effects against B. cucurbitae but also inhibited the progeny development. The lowest number of larvae (0.67) and pupae (0.67) recovery and adult emergence (0.33) was recorded from water pepper weed extract at 5.0% concentration followed by croton weed extract. The order of toxicity of the weed extracts based on repellency and oviposition deterrent was water pepper > croton > black nightshade > goat weed > common lucas > mexican poppy. However, progeny recovery, percent repellency and oviposition deterrent were found dose dependent manner. The highest repellency (53.05%) and oviposition deterrent (95.40%) were found in water pepper as against the lowest repellency (28.73%) and oviposition deterrent (44.96%) was in common lucas. The highest percent reduction of pupae recovery was observed in water pepper (97.53%) whereas the lowest was in mexican poppy weed extract (63.86%). The water pepper weed extract also showed the highest inhibition of adult emergence (98.72%). It is evident from the results that all the weed extracts caused a remarkable decrease in adult emergence, larvae and pupae recovery, and adult settling compared to control.

Keywords: Bactrocera cucurbitae, weed extract, repellent, oviposition deterrent, progeny development.