author(s)
Ruma Bose, Sahadat Hossain, M Khalequzzaman, Shakil A Khan and M Aftab Hossain

abstract
The experiment was conducted to study the population fluctuation of adult males of melon fly, Zeugodacus cucurbitae (Coq.) in different backyard vegetable gardens of Rajshahi University Campus from July 2014 to January 2015 and radiosensitivity of late age pupae to gamma radiation for determining the appropriate sterility dose. On average, the highest (77.19±19) fruit fly population per trap/month was recorded in August and the lowest was (12.29±0.70) in January. From the experimental results, it was observed that temperature, relative humidity and host availability influenced the melon fly population. It was noted that gamma radiation significantly prolonged the pupal duration (p<0.01). The longevity of irradiated flies was significantly decreased gradually at higher irradiation doses (p<0.01). The sterility percentage of the melon fly increased as the dose increased. Cent percent male sterility was achieved at 60 Gy. Therefore, sterile males should be released at optimum ratios at right time for getting the maximum output.