Tunisia is a country where agriculture is a top priority. Unfortunately, the annual rainfall is very irregular both in space and time. In this context, the present work has set as objective the valorization of cucurbits represented by four local accessions could help farmers to overcome the depressive effects of drought and water deficit. The germination kinetics and the final germination rate which were carried out on four seed lots of local squash accessions showed that the different concentrations of D-Mannitol clearly improve the final germination rate of the local accession Batati orange.The results showed that the different concentrations of D-Mannitol which generates a state of water stress causes numerous physiological disturbances at the level of the aerial parts of the plants of the local accessions Béjaoui and Galaoui. To alleviate this oxidative damage caused by water stress, plants set up defense barriers to lower the overproduction of reactive oxygen species (ROS).