Induced drought affects morphological and eco-physiological response of Mediterranean wild roses

Water scarcity for the irrigation of ornamental crops is a typical phenomenon of nursery activities in the south Mediterranean districts and has frequently detrimental effects on plant growth, yield and quality. Wild roses are generally hardy plants with high ornamental potentialities and possible tolerance to the main abiotic stresses typical of their native environments. Therefore, a greenhouse experiment was carried out with the aim to evaluate growing and qualitative response of two Sicilian rose species to increasing deficit irrigation. Rooted-cuttings plants of Rosa canina L. and R. sempervirens L. were grown in 4-L plastic containers under drought stress induced by progressively reducing the irrigation volumes (900, 600 and 300 mL plant^‑1) during each irrigation. Morphological and eco-physiological parameters were measured throughout the experiment. Increasing irrigation deficit resulted in a decrease of plant growth (at canopy and root level), ornamental effect, biomass yield and partitioning, stem water potential, leaf net photosynthesis and transpiration; this behavior was more evident in R. canina than in R. sempervirens potted plants. The identification of wild roses tolerant to moderate drought may allow to use them for ornamental nursery production and for landscaping in south Mediterranean areas often characterized by a low availability of the irrigation water.