Photoperiodic induction of flowering in Chenopodium rubrum L. might be controlled by an oscillatory mechanism

Abstract

Summary Long-term recordings of bioelectric potential difference across intact Chenopodium rubrum L. plants have been performed by subjecting them to different conditions for flowering during 10 days. Switching the light-on/off caused transient changes of the potential difference and the photosynthetic process was the major generator of those transients. Besides these transients, with average amplitude of 32 mV and duration of 22 min, self-sustained oscillations of the potential difference were also observed predominantly in the light-on period. The form of the individual spontaneous transients was usually similar to the light-induced transients, lasting 10–15 min, with an average amplitude of 6–7 mV. As the age of the plant increases, the frequency of the oscillations increased to more than four spikes per hour for some induced plants. With induced plants the oscillations were more ordered and of higher frequency. The results obtained point to the possibility that a frequency-controlled oscillatory bioelectric mechanism might be one of the initial steps in flowering control.