photoperiod

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Related to photoperiods: sporophyte, gametophyte

photoperiod

 [fo´to-pēr″e-od]
the period of time per day that an organism is exposed to daylight (or to artificial light). adj., adj photoperiod´ic.

photoperiod

/pho·to·pe·ri·od/ (fo´to-pēr″e-od) the period of time per day that an organism is exposed to daylight (or to artificial light).photoperiod´ic

photoperiod

(fō′tō-pîr′ē-əd)
n.
The daily duration of light and dark to which an organism is exposed, considered especially with regard to its effect on growth and development.

pho′to·pe′ri·od′ic (-ŏd′ĭk) adj.

photoperiod

the length of daylight as compared with the length of darkness in each 24 hour cycle. see PHOTOPERIODISM.

photoperiod

the period of time per day that an organism is exposed to daylight (or to artificial light).
References in periodicals archive ?
Regarding 2), although inbred mice may be genetically identical, perinatal photoperiods may nevertheless--by imprinting the circadian clock--lead to a differential stability of circadian rhythms.
Effects of different photoperiods and wavelengths of light on the life-history traits of an aphidophagous ladybird, Coelophora saucia (Mulsant).
The physiological basis for tuberization under long photoperiods involves biochemical and molecular signals that link photoperiod perception in leaves to changes in cellular growth patterns in stolons (Rodriguez-Falcon et al.
All groups were held under artificial photoperiod of (18L: 6D) using electric horologe of an intensity of 72 watts.
Two trials of accelerated yearly variations of temperature and photoperiod were conducted to uncouple the specific role of these factors in the timing of gametogenesis and sex of gametes over several spawning cycles.
Researchers evaluated the ability of avian embryos to integrate cues of season from photoperiod and maternal environments present in eggs to produce season variation among phenotypes among Franklin's gull (Leucophaeus pipixcan) hatchlings.
Lien RJ, Hess JB, McKee SR, Bilgili SF and JC Townsend Effect of light intensity and photoperiod on live performance, heterophil-lymphocyte ratio and processing yields of broilers.
External cues, like temperature changes and changes to the food supply, become obvious when the photoperiod changes more drastically.
4], observed in trout and goldfish, indicate a correlation with feeding and photoperiod (REDDY; LEATHERLAND, 1994), and also with temperature (ROZIN; MAYER, 1961; CUENCA; GALLEGO, 1987; HIGUERA, 1987; SMITH, 1989).
Animals were taken directly from the field and tested under normal and reversed photoperiods, as well as in constant dark and light.
Poulsen, 1940; Maemets, 1961; Flossner, 1964; Green, 1966; Frey, 1982; Koksvik, 1995), probably triggered by declining temperatures and shortening photoperiods (Shan, 1974; Frey, 1982).