light were used to compare the growth rates of plants ( Brown et al., 1995 ; Hogewoning et al., 2010 ). Most of these studies examined plant photomorphogenesis after exposure to different wavelengths of light and how it could be applied to shorten the
potentially optimize seedlings by stimulating plant photoreceptors that regulate growth and morphology (photomorphogenesis) ( Gómez and Mitchell, 2015 ). The emerging high-intensity LED lamps are an alternative for supplemented photoperiods due to their long
Description of the light environment used in photomorphogenic research varies greatly among research teams. The environment is often described as the ratio of red (R) to far-red (FR) light, particulary when involvement of the phytochrome system is suspected. There is disagreement in the appropriate center and range of values for each ratio component. Often the center for R is reported as 660 nm. However, in chlorophyll-containing tissue 645 nm may be more appropriate because of the absorption of chlorophyll at 660. Band widths around a selected peak also vary. The widths generally are 10 or 100 nm. Comparison of experiments that describe different peaks or ranges is difficult. Much of the variation in description results from the behavior of phytochrome. Phytochrome has absorption and action spectral peaks, however wavelengths that cause absorption and/or action to a lesser extent may extend more than 50 nm from the peak. Integration formulas such as Pfr/P consider the effects of all wavelengths. However, even the integration formulas do not explain all photomorphogenic responses. A description of the entire photomorphogenic spectrum may be the most appropriate means of communication.
) ( Gutschick and BassiriRad, 2003 ). Light-inducible sensing and signaling networks are present in plants and thus, plant acclimation responses can be engaged to promote and shape PSN and photomorphogenesis. The plant attributes modulated by either irradiance
Arabidopsis CULLIN4-damaged DNA binding protein 1 interacts with CONSTITUTIVELY PHOTOMORPHOGENIC1-SUPPRESSOR OF PHYA complexes to regulate photomorphogenesis and flowering time The Plant Cell Online 22 108 123 Chen, M. Chory, J. Fankhauser, C. 2004 Light
cryptochrome 2 contains flavin semiquinone J. Biol. Chem. 282 14916 14922 Brown, C.S. Schuerger, A.C. Sager, J.C. 1995 Growth and photomorphogenesis of pepper plants under red light-emitting-diodes with
.E. Kronenberg, G.H. 2012 Photomorphogenesis in plants. 2nd ed. Springer-Verlag, Berlin, Germany Latimer, J.G. Whipker, B. 2013 Selecting and using plant growth regulators on floricultural crops. 20 Mar. 2017. < https
systems HortScience 43 1957 1964 Goins, G.D. Yorio, N.C. Sanwo, M.M. Brown, C.S. 1997 Photomorphogenesis, photosynthesis, and seed yield of wheat plants grown under red light-emitting diodes (LEDs) with and without supplemental blue lighting J. Expt. Bot