RESPONSE OF MALE CODLING MOTHS (CYDIA-POMONELLA) TO COMPONENTS OF CONSPECIFIC FEMALE SEX-PHEROMONE GLANDS IN-FLIGHT TUNNEL TESTS

In flight tunnel tests, the percentages of oriented upwind flights of male codling moths culminating in contacting a source of different compositions of female sex pheromone gland components were determined over a dosage range of 0.1-100,000 mug. The following compositions were tested: (1) (E,E)-8,10-dodecadien-1-ol of 99.7% isomeric purity; (2) 1 + dodecan-1-ol + tetradecan-1-ol; (3) 2 + decan-1-ol + (E)-9-dodecen-1-ol; and (4) an equilibrium mixture of 8,10-dodecadien-1-ol isomers (61% EE, 5% ZZ, 14% ZE, and 20% EZ). The ratios of the components in compositions 2 and 3 were chosen to produce vapor ratios equal to the natural ratios found in the female effluvium by Am and coworkers. As the dose of composition 1 was increased from 0.1 to 10 mug, response increased from 0 to about 80% and then was approximately constant from 10 to 300 gg. Over the range 0.1-300 mug, the percentage of males contacting the septum was virtually the same as the percentage flying upwind. From 300 to 100,000 mug, the percentage of males flying upwind and contacting the source steadily decreased from about 80 to 0%. The male responses to compositions 2 and 3 were virtually identical to the response to 1. These results indicate, contrary to published reports, that dodecan-1-ol and tetradecan-1-ol in combination with 1 do not increase the responses of the behavioral modes determining degree of attractancy and disruption of sexual communication over that of 1 alone. These results also show that decan-1-ol and (E)-9-dodecen-1-ol do not enhance response in the five-component mixture. The response to composition 4 increased from 0% at a dose of 0.3 mug to 26% at a dose of 30 mug and then decreased to 0% at a dose of 3000 mug. Thus, the inhibiting effect of the isomers on response was greater at the higher doses.