Do memory processes occur also in plants

Plantlets of Bidens pilosus L. “remembered” a symmetry-breaking signal (the puncturing of one of the cotyledons), but expressed it only after being made permissive (by removing the apex). The mean value of the memorization index was 0.52. There was a labile short-term and a well-fixed long-term memory. The memorization process was dependent on the number of stimuli, and on the mineral status of the plant.