photophil

photophil

1. The phase of a two-phase circadian rhythm associated with light and expenditure of energy.

   Coordinate term: skotophil

   • 1975, Science progress - Volume 62, page 120:

     It will be seen that light at one phase of the rhythm promoted flowering, and at the other phase inhibited it; thus there was a distinct manifestation of photophil and skotophil phases.

   • 2010, Randy J. Nelson, David L. Denlinger, David E. Somers, Photoperiodism: The Biological Calendar, →ISBN, page 12:

     Short-day effects were seen to result when light was restricted to the photophil, while long-day effects were produced when light encroached into scotophil (figure 1.2).

   • 2013, Beatrice M. Sweeney, Rhythmic Phenomena in Plants, →ISBN, page 118:

     He postulated that light falling on the plant in the scotophil phase would inhibit flowering, and in the photophil phase, enhance flower production.

• photophile