Medical Entomology and Zoology (2001) 52, 255-257

Kazuyoshi Fujimoto (2001)
Morphogenetic diapause of engorged Amblyomma testudinarium Koch nymphs (Acari: Ixodidae) induced by short-day photoperiods
Medical Entomology and Zoology 52 (3), 255-257
Abstract: In order to clarify whether or not engorged Amblyomma testudinarium Koch nymphs exhibit morphogenetic diapause, their development was observed at 25°C under four photoperiodic conditions (10L-14D, 11L-13D, 12L-12D, and 16L-8D). The molting of the engorged nymphs was little affected by the exposure to 12L-12D and 16L-8D photoperiods. However, the molting was retarded or arrested by the exposure to 10L-14D and 11L-13D photoperiods. These results suggest that engorged A. testudinarium nymphs enter morphogenetic diapause under short-day photoperiods. Judging from the percentage of molting, their critical photoperiod for the induction of diapause appeared to be close to 11 hr. Thus, a part of the A. testudinarium nymphs that are active in autumn enter morphogenetic diapause and hibernate in the engorged state.
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Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Amblyomma testudinarium		Japan