Variations nycthémérales de l'intensité des corrélations entre les cotylédons et leur bourgeon axillaire induites par des traumatismes faits unilatéralement sur l'un des deux cotylédons de Bidens pilosus

Different methods (physiological, electrophysiological and biochemical) were used in order to show, during a 24 h period, a change in sensitivity of Bidens pilosus seedlings to the pricking of one of the cotyledons. The sensitivity is maximum in the morning and in the evening; it decreases during the light period (day) and the dark period (night). The minimum of the sensitivity occurs in the middle of the day and 3 to 4 h after the beginning of the night.