1.Effect of pheromone concentration on organization of preflight behaviors of the male gypsy moth,Lymantria dispar(L.).
Hagaman TE1, Cardé RT. J Chem Ecol. 1984 Jan;10(1):17-23. doi: 10.1007/BF00987639.
Male gypsy moths (Lymantria dispar L.) in a wind tunnel at 24° respond to decreasing dosages (1 μg to 0.1 pg) of (+)-cis-7,8-epoxy-2-methyloctadecane with a decrease in probability of wing-fanning, an increase in wing-fanning latency, and an increase in the number of behaviors (body jerks, antennal twitches, steps, and wing tremors) preceding fanning. Males initiating any behavior prior to wing-fanning had a 70% probability of wing-fanning and 97% of the males that wing-fanned eventually flew. The sequence of behaviors from quiescence to flight is not organized in a hierarchy, as this concept is used in ethology, nor is it dependent upon the concentration of pheromone. The time-average threshold concentration of pheromone for response of ca. 90% or more quiescent males is ca. 1.9 × 10(-17) g/cm(3) over < 0.3 min.
2.Diel periodicity and influence of age and mating on sex pheromone titer in gypsy moth,Lymantria dispar (L.).
Tang JD1, Charlton RE, Cardé RT, Yin CM. J Chem Ecol. 1992 May;18(5):749-60. doi: 10.1007/BF00994612.
The diel periodicity of sex pheromone titer from pheromone glands of femaleLymantria dispar is described. On the day of emergence (day 0), pheromone titer was generally low; means ranged from 1 to 4 ngcis- 7,8-epoxy-2-methyloctadecane during photophase and gradually increased to 8.4 ng over the course of scotophase. For day-1, -2, and -3 females, the diel fluctuations of titer were more pronounced. Lowest titers (5-9 ng) occurred 0-4 hr after lights-on, and peak titers (19-32 ng) were found 0-4 hr before lights-off. Comparison of the average daily titer among the different age groups (data pooled over six time points at 4-hr intervals) indicated that significantly less pheromone was extracted from glands of day-0 (4.5 ng) than day-1 (12.4 ng), day-2 (15.4 ng), or day-3 females (13.5 ng). No significant differences were found among the three older ages. Femalesin copula exhibited a rapid reduction in titer within the first 0.5 hr of mating initiation (7.
3.Reproductive character displacement in Lymantria monacha from northern Japan?
Gries G1, Schaefer PW, Gries R, Liska J, Gotoh T. J Chem Ecol. 2001 Jun;27(6):1163-76.
Our objective was to test the hypothesis that the pheromone blend and/or diel periodicity of pheromonal communication differ in populations of the nun moth, Lymantria monacha (Lepidoptera: Lymantriidae), from eastern Asia (northern Honshu, Japan) and Central Europe (Bohemia, Czech Republic). Coupled gas chromatographic-electroantennographic detection (GC-EAD) analyses of pheromone gland extract of female L. monacha from Japan confirmed the presence of compounds previously identified in pheromone extracts of L. monacha from Bohemia, as follows: (Z)-7-octadecene, 2-methyl-(Z)-7-octadecene (2me-Z7-18Hy), cis-7,8-epoxy-octadecane (monachalure), and cis-7,8-epoxy-2-methyloctadecane (disparlure). Field experiments in Honshu suggested that (+)-monachalure is the major pheromone component of L. monacha. 2me-Z7-18Hy significantly enhanced attractiveness of (+)-monachalure. Addition of (+)-disparlure to (+)-monachalure plus 2me-Z7-18Hy in Honshu and Bohemia increased attractiveness of lures by 1.
4.(7R,8S)-cis-7,8-epoxy-2-methyloctadec-17-ene: a novel trace component from the sex pheromone gland of gypsy moth, Lymantria dispar.
Gries R1, Khaskin G, Schaefer PW, Hahn R, Gotoh T, Gries G. J Chem Ecol. 2005 Jan;31(1):49-62.
Considering the vast Eurasian distribution of gypsy moth, Lymantria dispar (Lepidoptera: Lymantriidae), the many subspecies, and their presence in different lymantriid communities, we tested the hypothesis that L. dispar populations in eastern Asia employ one or more pheromone components in addition to the previously known single component pheromone (7R,8S)-cis-7,8-epoxy-2-methyloctadecane [= (+)-disparlure]. Coupled gas chromatographic-electroantennographic detection (GC-EAD) analyses of pheromone gland extracts of female L. dispar sensu lato (including both AGM and NAGM) on four GC columns (DB-5, DB-23, DB-210, and SP-1000) revealed a new trace component that eluted just before (DB-5; DB-210) or after (DB-23, SP-1000) disparlure, and elicited strong antennal responses. Isolation of this compound by high-performance liquid chromatography and hydrogenation produced disparlure, suggesting that the new component had the molecular skeleton of disparlure, with one or more double bonds.