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Related to phytochrome: Cryptochrome


Any of several photoreceptive pigments in green plants that regulate processes such as flowering and seed germination.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Botany) botany a blue-green pigment existing in two interchangeable forms, present in most plants, that mediates many light-dependent processes, including photoperiodism and the greening of leaves
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈfaɪ təˌkroʊm)

a plant pigment that is associated with the absorption of light in the photoperiodic response and that may regulate various types of growth and development.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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Phytochrome B Negatively Affects Cold Tolerance by Regulating OsDREB1 Gene Expression through Phytochrome Interacting Factor-Like Protein OsPIL16 in Rice.
This result may be related to the state of physiological dormancy of these seeds, since wild species generally present mechanisms of dormancy and light is linked to the activation of the phytochrome system, in turn, related to the functioning of cell membranes.
Because phytochrome is not sensitive to light when seeds are dehydrated (Kendrick & Spruit, 1977; McCullough & Shropshire, 1970), T.
(2008) a red light is important in the development of the photosystem complex providing morphogenetic changes of phytochrome while blue has been identified as affecting chlorophyll concentrations, photomorphogenesis and stomatal openings, thus a combination of blue and red wavebands at intensities which vary according to the species, can result in higher photosynthetic activity and better photomorphogenetic characteristics than red or blue alone.
The Indian contributors describe the role of phytochrome and B vitamins in physiological plant processes, mechanisms of metalloid uptake, sucrose nonfermenting-1 related kinase-1 (SnRK1) signal transduction during stress conditions, sugarcane seed germination, the effect of wastewater irrigation on crop health, and morpho-physiological responses of wheat genotypes under high temperature stress.
Evidence for phytochrome regulation of gibberellin A 20 3b-hydroxylation in shoots of dwarf (lele) Pisum sativum L.
Phytogeny of Andropogoneae inferred from phytochrome B, GBSSI and NDHF.
Furthermore, genetic and molecular studies have advocated that DOF proteins are implicated in the regulation of biological processes exclusive to plants, for instance, light-responsiveness, photoperiodic flowering, tissue differentiation, dormancy, seed germination and maturation, metabolic regulation and nitrogen assimilation and phytochrome and phytohormone signalling (Gupta et al., 2015; Noguero et al., 2013; Yanagisawa et al., 2004).