EFFET DE L’INTENSITÉ DE LA CONTRAINTE HYDRIQUE SUR LA GERMINATION DE Ziziphus lotus (L.) LAM. DES RÉGIONS ARIDES DE LA TUNISIE

Abstract

Our study focuses on the germination of Ziziphus lotus (L) Lam., Under water stress by applying different concentrations of PEG6000 on seeds from arid regions of Tunisia. We recorded that germination is even lower then water stress increases. The maximum rate of germination obtained was (100%) for the control of the National Park from Bouhedma (Z1). while the lowest percentages were recorded for treatment (-10) bars. The lag phase increases with water stress, the most extended (7 days) is recorded with (-10) for the bars from Matmata (Z3). For all treatments, it appears that the germination capacity varies among locations and depending on the osmotic potential. There is a decrease in the rate and germination capacity in parallel with the increase in latency mainly in treatments (-6, -8) and -10 bars.