Circadian rhythmicity is involved in photoperiodic time measurement in the aphidMegoura viciae
- Cite this article as:
- Vaz Nunes, M. & Hardie, J. Experientia (1993) 49: 711. doi:10.1007/BF01923957
The photoperiodic clock in the vetch aphidMegoura viciae is generally accepted to be based on a non-circadian mechanism or “hourglass”, as no evidence has been found for the involvement of the circadian system in the photoperiodic response. By using a recently-devised protocol which discriminates between single and repeated night length measurement, we demonstrate here that long-night measurement inMegoura is executed in a repetitive way, and thus that its photoperiodic clock is based on a circadian oscillator after all. However, it is also apparent that the determination of short nights is not repetitive.