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Related to photoperiodism: vernalization


An organism's response or ability to respond to changes in photoperiod.
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) the response of plants and animals by behaviour, growth, etc, to photoperiods
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌfoʊ təˈpɪər i əˌdɪz əm)

also pho•to•pe•ri•o•dic•i•ty (-ˌpɪər i əˈdɪs ɪ ti)

the effect of photoperiods on an organism's growth, fitness, and behavior.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

photoperiodism, photoperiodicity

the effect on the growth and reproduction of plants or animals of varying exposures to light and darkness. Cf. thermoperiodism. — photoperiod, n.photoperiodic, adj.
See also: Biology
the study of the relative amounts of light and darkness in a 24-hour period required to best effect the growth, reproduction, and flowering of plant species or the growth and reproduction of animals. Also photoperiodicity. Cf. thermoperiodism. — photoperiodic, photoperiodical, adj.
See also: Plants
-Ologies & -Isms. Copyright 2008 The Gale Group, Inc. All rights reserved.


The response of plants to changes in day length, e.g. flowering.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited
References in periodicals archive ?
Influences of photoperiodism and light treatments during fruits storage on the phytochrome and on the germination of Cucumis prophetarum L.
In Autumn the plant is ready to begin the process of photoperiodism, which is the physiological response poinsettias have leaves changing color to the variation in light as nights grow longer.
Whereas the evidence for seasonality driven by photoperiodism in many animals and plant species is widespread and compelling, such evidence is less developed for humans.
Interrelation of temperature and photoperiodism in the production of fruit-buds and runners in the strawberry.
In chronobiological terminology, Darwin's "mimic art" resembles modern understandings of how plants' internal or endogenous rhythms display photoperiodism, or responses to seasonal changes in day length, "by entraining, or locking on to, the driving oscillation of the environment in what is called photic entrainment or photoentrainment." (24) Physically sensing solar, external, or exogenous rhythms in their environment, these flowers "count the quick vibrations of [Time's] wing." In this way, Darwin presses the chronobiological importance of both internal and external rhythms in producing organisms' timekeeping capacities.
Photoperiodism: adaptation of day-length sensitive beans and corn in Tennessee.
Variability in diapause propensity within populations of a temperate insect species: interactions between insecticide resistance genes and photoperiodism. Biological Journal of the Linnean Society 83: 341-351.
Insect photoperiodism: effects of temperature on the induction of insect diapause and diverse roles for the circadian system in the photoperiodic response.