Physiological studies on pea tendrils. V. Membrane changes and water movement associated with contact coiling.

The coiling of excised pea tendrils in response to mechanical stimulation is accompanied by an increased efflux from their cut bases of electrolytes and label from previously absorbed (14)C-acetate and (14)C-sucrose. The major excreted cation is H(+); H(+) loss is potentiated by pretreatment with benzoic acid, which also leaves the tendrils during coiling.Label from previously absorbed tritiated water is excreted during coiling, mainly from the ventral side of the tendril, which contracts in the initial phase of coiling. Such label does not pass from the ventral to the dorsal side. Similarities between this and other rapidly moving systems in plants are surveyed and a hypothesis to explain turgor movements is advanced.