The Canadian Entomologist (2019) 151, 456-464

Sergey Y. Reznik and Natalia D. Voinovich (2019)
The photoperiodic response to single nights suggests a rapidly damping oscillator in Trichogramma telengai (Hymenoptera: Trichogrammatidae)
The Canadian Entomologist 151 (4), 456-464
Abstract: It is known that diapause-inducing effect of ultra-long (16–18 hours and longer) nights on insects with a facultative winter diapause is often weaker than that of "natural" long (usually 10–14 hours) nights. The weak diapause-inducing effect of ultra-long nights can be explained, in particular, in the frames of the external coincidence model of photoperiodic time measurement with a circadian oscillator, which damps under ultra-long nights. Based on this model, it can be expected that (1) the first ultra-long night would have the same diapause-inducing effect as natural long night because the damping of the oscillator will not manifest itself before the next light–dark cycle and (2) the diapause-inducing effect would decrease with the increase in the number of succeeding ultra-long nights. However, these hypotheses have never been tested with any insect species. We investigated progeny diapause-inducing effect of single and multiple nights of different lengths on Trichogramma telengai Sorokina (Hymenoptera: Trichogrammatidae) pupae and adult females. The results of the study support the external coincidence model with a damping circadian oscillator and suggest that in T. telengai the oscillator damps out after one or two cycles.
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Link to article at publishers website
Database assignments for author(s): Sergey Ya. Reznik

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
Trichogramma telengai (parasitoid)