DISRUPTION MECHANISMS OF PHEROMONE COMMUNICATION IN THE EUROPEAN GRAPE MOTH LOBESIA-BOTRANA DEN AND SCHIFF .3. SENSORY ADAPTATION AND HABITUATION

Disruption experiments were carried out under vineyard conditions and in the laboratory. Males from laboratory cultures were conditioned in an atmosphere permeated with pheromone (E7 Z9-12Ac), marked externally with fluorescent powder, and released in the middle of vine plots. Th ey were then trapped in a series of traps baited with virgin females o r dispensers loaded with various amounts of pheromone. Over 10,000 mal es were released in these experiments between 19 May and 22 July. Elec troantennography tests were used for studying olfactory sensitivity in pheromone-permeated air by measuring the EAG responses of male antenn ae in constant pheromone airflows. The conclusion is that both sensory adaptation and central nervous system habituation mechanisms acted si multaneously in air laden with pheromone, but they are probably not re levant when concentrations are of the same order of magnitude as those obtained under field conditions in which mating disruption methods ar e used for controlling the European grape moth.