Comparative anatomical and physiological characteristics of <i>Ranunculus glacialis</i> and estimation of its adaptive potential in natural habitats and the PABGI nursery (Murmansk region)

Abstract

Ranunculus glacialis (L.) A. Löve & D. Löve is a rare species that is included in the Red Data Book of the Murmansk region. It belongs to a group of northern species that, under climate change conditions, will be exposed to a reduction of range and loss of genetic diversity. The objective of this study was to estimate the adaptive potential of this species in the Khibiny Mountains, which is the edge of the eastern limit of its range. Plants growing in natural conditions of the Khibiny Mountains and in the nurseries of the  Polar-Alpine Botanical Garden-Institute (PABGI) were compared in terms of leaf mesostructure and pigment content. Under nursery conditions, at higher temperature than in the field, R. glacialis plants showed quantitative rearrangement of leaf mesostructure. Changes associated with increases in internal leaf volume and disturbance of ontogeny, changes in morphometric indicators of assimilating organs (mass and leaf area), reduced productivity and, consequently, reduced resistance to growing conditions were also found in the PABGI-cultivated plants. In this study, we show that this species has a low level of genetic diversity and a limited adaptive potential in the extreme eastern edge of its range in Russia (Kola Peninsula), as evidenced by numerous experiments on acclimatization of R. glacialis under nursery conditions in the Khibiny Mountains.