著者

Nishizuka Makoto Azuma Atsuki Masaki Sinzo

出版者

Entomological Society of Japan

雑誌

Entomological science (ISSN:13438786)

巻号頁・発行日

vol.1, no.1, pp.7-14, 1998-03-25

参考文献数

19

被引用文献数

2

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To elucidate the diapause pattern of Lepisma saccharina Linnaeus, strains collected in Hirosaki were kept under controlled conditions of photoperiod and temperature. The interval between moults was uniformly short in the first two instars, but tended to increase in the later instars and showed a very large variation owing to the occurrence of diapause in some individuals but not in others. When reared at 25℃, this insect started oviposition in the 9th or 10th instar but thereafter continued to grow and moult. Some individuals survived 2.5 years or more and moulted more than 30 times. The incidence of diapause as defined by the instar duration of longer than 50 days was affected by temperature, photoperiod and age. The duration of diapause was highly variable among individuals, lasting more than 180 days at 25℃ in extreme cases. Diapause may occur in any larval and adult instar but not in the first two instars, and may be repeated in separate or consecutive instars. Some individuals underwent 8-9 diapause instars in 600-800 days. At 20℃, diapause occurred in the younger (3rd and 4th) instars at a higher frequency, and a photoperiodic response of the long-day type was manifested more clearly, than at 25℃. A high temperature of 28℃ prevented diapause at least in the larval stage under both short (12h) and long (16h) photoperiods.