Influence of the moisture content of the substrate on the emerging ability of adults of Muscidifurax zaraptor Kogan & Legner, Nasonia vitripennis (Walker) (Hymenoptera Pteromalidae) and Musca domestica L. (Diptera Muscidae)

Abstract

The ability to move up to the surface of Muscidifurax zaraptor Kogan & Legner, Nasonia vitripennis (Walker) and Musca domestica L. from puparia placed at different depths in substrates with different moisture content was verified. Tests were carried out at 27±1°C and 70±5% R.H.; as substrate was used bran with three different initial moisture contents (15, 60 and 75%). The number of adults of M. zaraptor and N. vitripennis able to move up to the surface is more influenced than M. domestica by depth at which puparia are placed. In the substrate with 15% m.c. M. zaraptor and N. vitripennis are able to emerge from puparia placed at 3 cm depth; the ability of the first species is limited to 2 cm with 60% m.c., while for the second species it remains the same. In the substrate with 75% m.c. adults of the two parasitoids are not able to reach the surface from puparia placed at 1 cm. In the substrate with 15% m.c. M. domestica emerging is not influenced till 6 cm depth; adults are not able to emerge from puparia placed at 20 cm depth. Only 5% of the adults is able to move up to the surface from puparia placed at 1 cm depth in the substrate with 75% m.c..