Augé RM, Schekel, KA, Wample RL. 1987. Rose leaf elasticity changes in response to drought acclimation and mycorrhizal colonization. Physiologia Plantarum 70: 175-182. Tissue elasticity can affect plant response to drought, in terms of turgor maintenance and water uptake from drying soils. The purpose of this study was to determine the effect of mycorrhizal colonization and drought acclimation on rose (Rosa hybrida L. cv. Samantha) leaf elasticity. Bulk elasticity was characterized by the pressure-volume methods using plots of the elastic modulus as a function of leaf turgor pressure, total water potential and relative water content. The treatments, arranged in a 2x3 factorial design, included acclimated and unacclimated plants, and either Glomus intraradicesSchenck and Smith, Glomus deseticola Trappe, Bloss and Menge, or a non-mycorrhizal control. Plants with root mycorrhizal colonization showed reduced leaf elasticity (i.e. higher elastic moduli) over a broad range of leaf water potential and water content. Both mycorrhizal colonization and acclimation facilitated the maintenance of positive values of turgor and elasticity at lower leaf water potential and water content than in controls. Mycorrhizal infections may aid plants in acclimating to water deficits through effects on leaf tissue elasticity.