ABSTRACT
The characteristics of the plant are under genetic control (see Chapter 9). However, the growth and development of the plant, from one stage of the life cycle to the next, take place in response to a number of stimuli, many of which are changes in the plant’s environment. The plant’s most reliable indicator of season, especially in temperate regions, is the daylength, which shortens and lengthens with the time of year. Annual temperature fl uctuations are a valuable, if less precise, indicator of seasonal occurrence.
