Plant growth and fitness of Scabiosa columbaria under climate warming conditions

Abstract

Background: Plants occupying wide altitudinal gradients may be adapted to their altitude of origin. Upward expansion of lowland populations in response to climate change might therefore facilitate species persistence at higher elevations by introducing pre-adapted genes. Aim: We compared plant growth and fitness in Scabiosa columbaria originating from low and high elevations (ca. 600 m and ca. 1200 m above sea level (a.s.l.)) under current and warmer climatic conditions to evaluate evidence for adaptation to altitude and phenotypic plasticity. Methods: Two approaches were used: a climate chamber experiment with current and warmer temperatures; and a common garden experiment at 600 m and 1200 m a.s.l. (two gardens each). Results: Performance of plants grown in their local environment was similar to plants from the foreign environment and independent of altitude of origin. Plant growth was reduced at low temperature. Growth and fitness did not differ between altitudes of treatments but varied among gardens. Reproduction in plants from higher altitudes increased in the lower gardens in one of 2 years of study. Conclusion: We found high phenotypic plasticity and no evidence for adaptation to altitude. Our results indicate that S. columbaria might have the capacity to persist in a warming world at higher elevation without additional gene inflow from lower altitudes.