Light Breaks and Fruit-Body Maturation in Coprinus congregatus: Dark Inhibitory and Dark Recovery Process

Abstract

Experiments were conducted to better understand the inhibitory effect of lightduring the dark-induced process of fruit-body sporulation of Coprinus congregatus Bull, ex Fr. Light-initiated fruit-body primordia were subjected to different dark periods interrupted by a short blue light break at different times. The sporulating response depended on the duration of the dark period following the light break. For any inductive dark period longer than 3.5 h, a period of darkness lasting half as long as the inductive night completely inhibited fruit-body maturation when given after the light break (dark inhibitory process). Longer dark periods after the light break causedrecovery of the maximal sporulating response (dark recovery process). The effects of the dark inhibitory and the dark recovery process were alternately reversible, the sporulating response depending on the duration of darkness after the last light break. Study of the time course of sporulation showed that a new dark-induced process of fruit-body sporulation was initiated by the beginning of the dark period after the light break.