Life cycle, thermal requirements and parasitism of Muscidifurax uniraptor on house fly pupae

Abstract

The pupal parasitoids are among the most important organisms responsible for house fly population reduction in poultry farms. Muscidifurax uniraptor Kogan & Legner (Hymenoptera: Pteromalidae) is one of the main parasitoids that occur in poultry farms at São Paulo State, Brazil. The objective of this study was to determine the life cycle duration, the thermal requirements and the parasitism of M. uniraptor on Musca domestica L. (Diptera: Muscidae) pupae under constant temperatures. The experiment was realized in climatized chambers at seven temperatures (18, 20, 22, 25, 28, 30 and 32 ± 1°C), 70 ± 10% R.H. and 14 h of photophase. In each chamber 200 house fly pupae (24 to 48 h old) were exposed to 40 partenogenetic female parasitoids (0 to 24 h old) for 24 h. The temperature influenced the development and reproduction of M. uniraptor. The lowest value of the egg-adult period was 17 days, and occurred for 30°C and the parasitism and progeny emergence were highest at 28°C (87 and 63.5%, respectively). The lowest temperature threshold for the parasitoid females was 9.43°C, with a thermal constant of 366.62 degree-days. The temperature elevation reduces the duration of the egg to adult period (between 18 and 30°C ) and increases the parasitism (between 18 and 28°C) of M. uniraptor. Temperatures between 28 and 30°C are the most adequated for rearing M. uniraptor on house fly pupae.