Flight behaviour of Cadra cautella males in rapidly pulsed pheromone plumes

摘要: Airborne pheromone plumes in wind comprise filaments of odour interspersed with gaps clean air. When flying moths intercept a filament, they have tendency to surge upwind momentarily, and then fly crosswind until another filament is intercepted. Thus, the moment-to-moment contact mediates shape flight track along plume. Within some range favourable interception rates, tracks become straighter are headed more due upwind. However, as rate increases, there comes point at which moth should not be able discern discreet but, rather, perceive 'fused signal'. At extreme, homogeneous clouds inhibit progress by representative tortricids. In tunnel, Cadra cautella (Walker) (Lepidoptera: Pyralidae) were presented 10 ms pulses repetition 5, 10, 17 25/s continuous, internally turbulent Pulse size concentrations verified miniature photoionization detector sampling surrogate odour, propylene, 100 Hz. Male maintain even 25 filaments/s. Furthermore, exhibited greater velocities headings Hz than lower frequencies or continuous It hypothesized that either C. possesses versatile sensory system allows resolution these rapidly pulsed plumes, this species does require 'flickering' signal