Responses of wild Piper species to drought and rehydration cycles considering stomatal closure as a marker of the alarm phase

Studies that simulate recurrent drought events with subsequent episodes of rehydration better reflect natural conditions and allow visualization differential acclimatization responses resulting from memory tolerance mechanisms. Piper aduncum tuberculatum were grown in a greenhouse subjected to three successive cycles rehydration. After suspending irrigation, gas exchanges measured daily IRGA. When stomatal conductances close zero obtained, the plants rehydrated kept irrigated. In P. tuberculatum, conductance was always higher after periods compared period before drought, while transpiration rate lower only during drought. The damage photosynthetic apparatus caused by influence interception flow electrons transport chain. We came conclusion dehydrated showed an alert signal, which triggered response mechanisms prevent or deal water stress situation.