Plant adaptation to extreme environmental conditions: morphological, physiological and biomolecular elements of salt and drought tolerance.

Abiotic stresses, especially salinity and drought, are the primary causes of crop loss worldwide. Water quality and availability play a crucial role in the determination of agricultural yield, and this is tremendously true in extreme environments such as those found in the Algerian steppe, where most of the stresses that can affect plant growth are simultaneously occurring. Indeed, plants have evolved a series of mechanisms (ranging from morphological to physiological and bio-molecular adaptations), that allow their life to take place even in harsh conditions as such. Modern agricultural technologies address the reduction of the stress incidence by the creation of environments where the pressure imposed to the plants is reduced or avoided. However the access to these technologies is still limited to large scale market-oriented farming and no alternatives are offered to peasant farming. Besides, the market itself has compelled farmers toward a limited range of genotypes that better suit the consumer preference, careless to their natural attitudes. Indeed learning from the plant experience may represent a sustainable strategy to improve agricultural performances. This paper will offer an overview of the systems that plant have naturally evolved to overtake environmental stresses and their possible application in current agriculture.