Electrolyte leakage differences between poikilohydrous and homoiohydrous species of Gesneriaceae

Comparative analysis of the electrolyte efflux, as a screening test of the membrane tolerance to water stress, was carried out in poikilohydric plants Ramonda serbica and Ramonda nathaliae and homoiohydric plant Saintpaulia ionantha from the same family Gesneriaceae. Water stress was induced by PEG 600. The high degree of solute leakage in the East-African drought-intolerant Saintpaulia ionantha points to the loss of membrane integrity. In contrast, Balkan endemites Ramonda serbica and R. nathaliae show high resistance to water stress due to the specific constitutional drought tolerance mechanisms.