MECANISES ADAPTATIFS DE L’HALOPHYTE SPONTANEE Sueada mollis SOUS DEUX REGIMES HYDRIQUES DIFFERENTS DE LA REGION DE OUARGLA

Abstract

Some aspects of spontaneous resistance of halophytes growing in the region of Ouargla were studied. The species selected are: Suaeda mollis, and for two periods (winter and summer) and two water regimes (continuous and discontinuous). The physico-chemical analyses of the rhizospheres indicates that the soil of Chott el Ain Beida is more salty than the farm which showed a variability of salinity as a result of irrigation. Testing of these species have yielded some information concerning the effect of salt on the mineral composition of different organs, their water, their content in soluble carbohydrates, proline and protein as a function of water regime. The Hydromineral status identifies the adaptive mechanisms of plants. This is the compartmentalization (inclusion) for Suaeda m. Proportionality between changes in the content of salt in rhizospheres with the evolution of the species content of toxic ions and compatible solutes such as total soluble sugars, proline and proteins is generally found. These elements are fragmented throughout the entire plant by the sequestration of toxic ions in older leaves, young leaves then benefit from increased protection. These in part accumulate against preferably compatible solutes contributing to osmotic adjustment.