Anthemis maritima L. in different coastal habitats: A tool to explore plant plasticity

Anthemis maritima, a plant which has the ability to colonise different stressful coastal environments, sand dunes and rocky cliff ecosystems, exhibits a high degree of leaf trait plasticity. The key parameters are the regulation of stomatal density and size, the succulence index and the specific antioxidant response. With the aim to explore plant plasticity, we analysed various morphological and physiological traits of the leaves of A. maritima populations dwelling in three different coastal areas of Italy. The highest values of stomatal density, leaf thickness, and succulence index were found in plants living in a sub-arid climate, on rocky cliffs, with the highest soil pH and salinity. Although this population exhibited the highest content of oxygen reactive species (hydrogen peroxide), it also revealed to have the lowest value of lipid peroxidation, an indicator of oxidative stress. Ascorbate was the main protective molecule in this population, while phenols appeared to carry out this role in plants living on soils with the lowest salinity and highest annual rainfall.