Physiological responses of Pistacia vera L. versus Pistacia atlantica Desf. to water stress conditions under arid bioclimate in Tunisia

- P. atlantica showed fast recovery of physiological parameters, compared to P. vera.
- P. atlantica presented physiological changes enabling it to adapt to water stress.
- P. atlantica is higher adapted to water stress compared to P. vera.

Water stress represents the major factor that affects the growth and development of plants in the arid and semi-arid areas. To improve crop management, the selection of better yielding species under such condition is a principal strategy. In this study, the responses of two pistachio species were studied after water stress followed by re-watering. Indeed, the leaf water potential, relative water content, total chlorophyll content and leaf gas exchanges were assessed during water stress and re-watering. The results showed that, under water stress, Pistacia atlantica Desf. maintained water status, leaf gas exchanges and total chlorophyll content stable compared to Pistacia vera L., which experienced a great decrease. After rehydration, P. atlantica showed fast recovery of stomatal parameters, compared to P. vera, suggesting a good tolerance to water stress. The variation of P. vera and P. atlantica responses to water stress and re-watering suggested the higher adaptation of P. atlantica to water stress compared to P. vera.