When and How They Flower

Krekule J., Macháčková I.

p. 57-60
In the second half of the 20th century the physiological study of flowering regulation focused on several plant species with photoperiodic reaction. The main aim was to discover a receptor of photoperiodical signals in leaves and also the endogen rhythm, i.e. a mechanism through which plants can perceive and measure the length of a day. Experiments were developed to determine the character of florigene as a substance initiating flower formation in apical meristems, as well as to describe corresponding anatomical and cytological changes.