ELEVATION OF PHEROMONE RESPONSE THRESHOLD IN ALMOND MOTH MALES PREEXPOSED TO PHEROMONE SPRAY

Citation
A. Mafraneto et Tc. Baker, ELEVATION OF PHEROMONE RESPONSE THRESHOLD IN ALMOND MOTH MALES PREEXPOSED TO PHEROMONE SPRAY, Physiological entomology, 21(3), 1996, pp. 217-222
Citations number
28
Categorie Soggetti
Entomology
Journal title
ISSN journal
03076962
Volume
21
Issue
3
Year of publication
1996
Pages
217 - 222
Database
ISI
SICI code
0307-6962(1996)21:3<217:EOPRTI>2.0.ZU;2-6
Abstract
High percentages of naive Cadra cautella (Walker) (Lepidoptera: Pyrali dae) males not pre-exposed to pheromone flew upwind to sources contain ing 50 ng (83%) and 500 ng (97%) of pheromone, but not to sources cont aining 5 mu g (23%) and 50 mu g (4%). Of the naive males that flew upw ind in response to 50 ng sources, 67% located and landed on the source , whereas fewer than 19% of the naive males that flew upwind in respon se to higher doses located and landed on the sources. A 2-minute pre-e xposure of C.cautella males to a spray cloud containing 50 ng, 500 ng, 5 mu g or 50 mu g of pheromone, induced shifts in response levels suc h that in wind-tunnel bioassays performed 1 h later, there was an incr ease in the doses that optimally elicited upwind flight and landing on the source that was proportional to the pre-exposure dose. Few of the pre-exposed males flew upwind to (10-43%) and landed on (0-33%) 50 ng sources, whereas they now perferentially flew upwind to (58-81% and 5 2-73%) and landed on (33-68% and 55-60%) pheromone sources of doses of 500 ng and 5 mu g, respectively. Therefore preexposure to pheromone p romoted a shift of threshold for response, and not an overall reductio n in responsiveness to pheromone.