effect of water (drought) stress on water relations of haloxylon aphyllum and h. persicum*

root and shoot osmotic and elastic properties of two species of haloxylon aphyllum and h.persicum in response to water stress were studied. the main goal of the study was to determine if the tissuesof two species utilize osmotic adjustment and/or enhance their elastic property during prolonged water stresscondition. the results showed that although tissue elasticity of both species of haloxylon was enhanced due toapplication of repeated water stress cycles, this condition also increased the tissue osmotic potential.therefore, this study concluded that haloxylon species utilize enhancement of elasticity rather than osmoticadjustment to maintain positive turgor and withstand drought