916 CUELLO
Figure 1 Daily profiles for conventional lighting (A) as a rectangular wave, whose height is the magnitude
of the photosynthetic photon flux (PPF) in mol m^2 sec^1 , whose length is the daily photoperiod in hr, and
whose area is the daily integrated PPF in mol m^2 day^1 , and for composite lighting (B) with a bell-shaped so-
lar component and a rectangular-wave artificial-lighting component.
Figure 2 Lighting profiles over two consecutive days: (A) for simultaneous composite lighting consisting of
a component with low PPF (PPF 1 ) and long photoperiod (P 1 ) and a second component with high PPF (PPF 2 )
and short photoperiod (P 2 ) and (B) for alternating composite lighting with each component alternating between
days.