Abstract: In this paper, a 32 channel, computer-monitored flight mill system fortesting the flight ability of small, weakly flying insects such as aphids was designed and presented. The flight mill construction, data collecting adapter and software design were described. The flight mill system is an optimal tool for studying small insects flight behavior. The flight ability of the bird cherry oat aphid (BCOA) Rhopalosiphum padi (Linnaeus) was tested with this flight-mill system. The results showed that the flight performance of the aphids varied with their ages. The. BCOA at 1 to 5-day old flew signifi- cantly longer than those at 7 to 9-day old. However, there was no significant difference in the average flight time among the BCOA with different ages, and the flight speed decreased with the increase of the aphid age.

Key words: aphid, flight mill, flight behavior, microcomputer