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Related to photoperiodism: vernalization


An organism's response or ability to respond to changes in photoperiod.


(Botany) the response of plants and animals by behaviour, growth, etc, to photoperiods


(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.

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


The response of plants to changes in day length, e.g. flowering.
References in periodicals archive ?
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.
Interrelation of temperature and photoperiodism in the production of fruit-buds and runners in the strawberry.
Biology of mammalian photoperiodism and the critical role of the pineal gland and melatonin.
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.
Variability in diapause propensity within populations of a temperate insect species: interactions between insecticide resistance genes and photoperiodism.
Statistical research has documented seasonal patterns described in terms of sociological and biological factors such as the variations of the circadian biological clock and photoperiodism, variety in terms of neurotransmitters, a.
Cannabis sativa is an annual plant, growing vegetatively in the early part of its life cycle, and induced to flower by photoperiod, the timing of induction being one of many adaptive features of the plant, discussed in this review (in the "Evolution of Photoperiodism Under Domestication" section).
Specific topics covered include insect-insect and insect-plant interactions, insect biotechnology for pest control, insect photoperiodism and many more.
Study of photoperiodism on gonadal weight in a Readhead bunting under natural day length [Ndl].
Extraretinal photoreception in entrainment and photoperiodism in invertebrates.
Among the topics are lessons on circadian clocks from fish, an update of the morning and evening oscillator model in Drosophila, dynamic neuronal network organization of the circadian clock and possible deterioration in disease, circadian modulation of sleep in rodents, local aspects of sleep revealed by observations from intra-cerebral recordings in humans, feedback actions of locomotor activity to the circadian clock, managing neurobehavior capability when social expediency trumps biological imperatives, the evolutionary physiology of photoperiodism in vertebrates, and circannual rhythm in the varied carpet beetle Anthrenus verbasci.