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Monema flavescens Walker (Lepidoptera: Limacodidae) is a multivoltine, generalist moth whose larvae cause serious damage to many types of trees. Pheromone lures prepared according to a study of a Japanese population were found to be ineffective at attracting M. flavescens nettle caterpillars in China, and some studies have shown intraspecific geographical differences in the composition of sex pheromones. We therefore reexamined the sex pheromone composition of M. flavescens in a Chinese population. In this study, the electroantennographically (EAG) active compounds in an extract from Chinese virgin females of M. flavescens were identified as (E)-8-decen-1-ol (E8-10:OH), (Z)-7,9-decadien-1-ol (Z7,9-10:OH), (Z)-9,11-dodecadien-1-ol (Z9,11-12:OH), and (Z)-9,11-dodecadienal (Z9,11-12:Ald) via coupled gas chromatographic-electroantennographic detection (GC-EAD) and coupled GC-mass spectrometry (MS). Pheromone dimorphism might occur in this species, as this mixture of compounds in Chinese females was different from that of E8-10:OH and E7,9-10:OH extracted from Japanese females in previous research. In wind tunnel and field tests, the males were significantly attracted to a blend of the pheromone components E8-10:OH, Z7,9-10:OH, and Z9,11-12:OH in a 100:5:4 ratio. The addition of Z9,11-12:Ald did not change the male response. The optimized three-component lure blend may provide a useful tool for monitoring and controlling Chinese populations of M. flavescens.

Extracts of the female sex pheromone gland of the carpenterworm moth, Holcocerus vicarius (Walker) (Lepidoptera: Cossidae), a pest of Ulmus pumila L. (Ulmaceae), were found to contain Z7-tetradecenyl acetate (Z7-14Ac), E3-tetradecenyl acetate (E3-14Ac), (Z3,E5)-tetradecenyl acetate (Z3,E5-14Ac), and Z7-tetradecenyl alcohol (Z7-14OH) by coupled gas chromatographic-electroantennographic detection (GC-EAD) and coupled gas chromatography-mass spectrometry (GC-MS). Field trapping studies with impregnated rubber septa indicated that Z7-14Ac was essential for attraction of males of H. vicarius. However, the most attractive blend contained Z7-14Ac, E3-14Ac, Z3,E5-14Ac, and Z7-14OH in a 50:22:17:10 ratio. Our results demonstrated that a blend of Z7-14Ac, E3-14Ac, Z3,E5-14Ac, and Z7-14OH represented the sex pheromone of H. vicarius. The optimized four-component lure blend may be useful for monitoring H. vicarius infestations and mating disruption.

The adult behavior and sex pheromone titers of Isoceras sibirica Alpheraky (Lepidoptera, Cossidae) were investigated to determine the diel periodicity of pheromone production during one scotophase and the effect of age on pheromone production. The results showed that females began to call on the first night after eclosion and called mainly during the second half of scotophase. The percentage of females calling was highest in 1- to 3-day-old females and lowest in 4- to 5-day-old females. The onset of scotophase calling occurred earlier as females aged. The responses to the pheromone source of males aged 1-5 days were monitored in a wind tunnel. Peak activity was observed in 3-day-old males, 4 h after the onset of the scotophase. The mating of all 1- to 3-day-old moths began after 6 h in scotophase and some 4- to 5-day-old moths began during the fourth hour. The average duration of copulation was 34.2 ± 18.2 min (N = 45) and ranged from 17.0 to 56.3 min. Gas chromatography-mass spectrometry (GC-MS) analysis of hexane extracts of pheromone glands revealed that the titers of the three sex pheromone components, (Z)-9-tetradecenyl acetate (Z9-14:Ac), (Z)-7-tetradecenyl acetate, and (Z)-9-hexadecadecenyl acetate were very low on the first night after eclosion, increased and peaked on the second night, then decreased with age. During the first 4 h of the scotophase, titers remained invariant, whereas from 4 to 6 h, pheromone titers increased sharply and peaked, with the greatest peak observed in the primary component, Z9-14:Ac. After the peak, all recorded titers declined until they reached a minimum between the ninth and tenth hours of the dark cycle. In field tests, most of the males were captured in traps during 00:00-02:00 h (13 ± 0.48), and females aged 2 days attracted more males than females of other ages. We infer that the I. sibirica mating system is organized around circadian control of mate calling and mating.