Termination of dormancy in seeds of many species
can be markedly triggered by light (Bewley and Black,
1982). A large body of information about phytochrome
stimuli of germination has accumulated since
the seminal work of Borthwick et al. (1952). Depending
on the dormancy state of the seeds, light treatment
(i.e., spectral composition, irradiance, duration), and
other environmental conditions, germination can be
promoted, inhibited or be indifferent to light (Bewley
and Black, 1982; Frankland and Taylorson, 1983;
Casal and SaÂnchez, 1998).