title: A pheromone analogue affects the evaporation rate of (+)-disparlure in Lymantria dispar.
abstract: BACKGROUND
  The gypsy moth Lymantria dispar L. is a widespread pest that causes economic damage to cork oak forests. Females produce the sex pheromone (+)-(7R,8S)-epoxy-2-methyloctadecane, known as (+)-disparlure [(+)D], for long-distance attraction of conspecific males. A (+)D analogue, 2-decyl-1-oxaspiro[2.2]pentane (OXP-01), neither stimulating nor attractive by itself, causes short-time inhibition of male response in a 1:1 blend with (+)D. The authors investigated whether and how the biological activity of the natural pheromone is affected by OXP-01 on a long-time basis (up to 16 days), also by looking at possible physicochemical reciprocal interactions.
  
  
  RESULTS
  Blending of (+)D with OXP-01 decreased, under low evaporation rate, the pheromone effectiveness, as assessed by electroantennogram recordings. In male trappings, within the first 24 h, OXP-01 decreased and later enhanced the blend attractiveness, but only under high evaporation rate. Gas chromatography-mass spectroscopy indicates that quantitative retrieval of (+)D from blend cartridges is higher than for pure pheromone, and nuclear magnetic resonance measurements show that OXP-01 produces, possibly by Van der Waals interactions, a bimolecular entity with pheromone causing retention and lengthening of its attractiveness over time.
  
  
  CONCLUSIONS
  The biological and physicochemical interactions between (+)D and OXP-01 may provide valuable information for the optimisation of pheromone-based control strategies for gypsy moths.
authors.affiliation: Department of Biomedical Sciences, Section of Physiology, University of Cagliari, Monserrato, Cagliari, Italy.
authors.forename: Giorgia
authors.initials: G
authors.lastname: Sollai
authors.forename: Sergio
authors.initials: S
authors.lastname: Murgia
authors.forename: Francesco
authors.initials: F
authors.lastname: Secci
authors.forename: Angelo
authors.initials: A
authors.lastname: Frongia
authors.forename: Anna
authors.initials: A
authors.lastname: Cerboneschi
authors.forename: Carla
authors.initials: C
authors.lastname: Masala
authors.forename: Anna
authors.initials: A
authors.lastname: Liscia
authors.forename: Roberto
authors.initials: R
authors.lastname: Crnjar
authors.forename: Paolo
authors.initials: P
authors.lastname: Solari
mesh_terms: D000473:Alkanes / Q000737:chemistry* / Q000494:pharmacology; D000818:Animals; D057506:Arthropod Antennae / Q000502:physiology; D001522:Behavior, Animal; D004594:Electrophysiology; D004852:Epoxy Compounds / Q000737:chemistry* / Q000494:pharmacology; D007558:Italy; D008297:Male; D009036:Moths / Q000502:physiology; D012724:Sex Attractants / Q000737:chemistry* / Q000494:pharmacology; D013141:Spiro Compounds / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D000473:Alkanes; D004852:Epoxy Compounds; D012724:Sex Attractants; D013141:Spiro Compounds; C001150:disparlure
keywords: behaviour; electrophysiology; insects; pheromone; self-diffusion nuclear magnetic resonance