Zoological Studies

Vol. 38 No. 3, 1999

A Potent Sex Attractant of the Male Tea Tussock Moth, Euproctis pseudoconspersa (Strand) (Lepidoptera: Lymantriidae) in Taiwan: Field and EAG Responses

Ru-Shiow Tsai1,2, En-Cheng Yang1, Chin-Yih Wu2, Hsin-Kuang Tseng3 and Yien-Shing Chow1,*

1Institute of Zoology, Academia Sinica, Taipei, Taiwan 115
2Department of Biology, National Taiwan Normal University, Taipei, Taiwan 116
3Taiwan Tea Experiment Station, Puhsin, Taoyuan, Taiwan 326

Ru-Shiow Tsai, En-Cheng Yang, Chin-Yih Wu, Hsin-Kuang Tseng and Yien-Shing Chow (1999) 10,14-Dimethylpentadecyl isobutyrate (10Me14Me-15:iBu) was identified from extracts of pheromone glands of the female tea tussock moth, Euproctis pseudoconspersa (Strand) by use of gas chromatography in Taiwan. EAG records showed that (R)- and (S)- enantiomers, and pheromone extract could elicit male antennal responses. Crude pheromone extract elicited a larger EAG response than did (R)-10Me14Me-15:iBu, but the EAG response to the (S)-enantiomer was smaller than that to crude extract or to the (R)-enantiomer. In field tests, the (R)-enantiomer showed greater attraction than did either the (S)-enantiomer or racemic mixtures in July 1998. However, later in the season, the (R)- enantiomer and racemic mixtures showed a similar attractancy, and both were better than the (S)-enantiomer. Traps baited with 20 g of racemic mixtures and those with 2 virgin females showed similar attractancies; however, more males were caught with 80-g baited traps.

Key words: Euproctis pseudoconspersa, 10,14-Dimethylpentadecyl isobutyrate, Enantiomers, Sex pheromone.

*Correspondence: E-mail: Chow@gate.sinica.edu.tw