thermopériode

CONT: Un autre facteur fondamental c'est la thermopériode, c'est-à-dire le rythme diurne ou annuel des températures. L'adaptation à ces variations thermiques est appelée le thermopériodisme.
CONT: Thermopériode [c'est la] succession des périodes froides et chaudes en cours d'année.

CONT: Thermoperiod refers to daily temperature change. Plants grow best when daytime temperature is about 10 to 15 degrees higher than nighttime temperature. Under these conditions, plants photosynthesize (build up) and respire (break down) during optimum daytime temperatures and then curtail respiration at night. However, not all plants grow best under the same range between nighttime and daytime temperatures. For example, snapdragons grow best at nighttime temperatures of 55°F; poinsettias, at 62°F.