Abstract
Diapause (100% incidence) occurs in the moth Pectinophora gossypiella when it is exposed to 24-hour light/dark cycles involving 12 hours of red light (600 nm); only 2% occurs when the photoperiod is extended to 14 hours, again with 600-nm light. This wavelength fails to synchronize all the known circadian oscillations of the moth. These observations appear, therefore, to constitute positive evidence that the photoperiodic time measurement is not mediated by a circadian oscillation. However, it remains possible, even plausible, that the photoperiodic clock is a separate circadian oscillator coupled to light by a red-absorbing pigment. That possibility is testable. The nature of the clock—oscillator or not—remains open.
Full text
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Selected References
These references are in PubMed. This may not be the complete list of references from this article.
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