Seasonal changes in photosynthetic rate and pigment content in two populations of the monotypic Balkan serpentine endemic Halacsya sendtneri

Abstract

Halacsya sendtneri (Boiss.) Dorfl. is an obligate serpentine palaeoendemic of the Balkan Peninsula. It is able to maintain a favourable magnesium:calcium (Mg:Ca) ratio throughout its root and shoot, and grow in serpentine habitats with different microclimate conditions. Seasonal variation of leaf chlorophyll and carotenoid contents showed a steep decline right after the spring period, which was most probably caused by the drought imposed on the plants on the shallow serpentine soil. However, the in situ photosynthetic rate remained stable throughout the spring and summer period. Prolonged photosynthetic activity enables this species an investment into root development and sustainable survival in the harsh soils of the habitats it occupies.