Phenotypic plasticity in two antarctic populations of Colobanthus quitensis (Caryophyllaceae) under a simulated global change scenario

作者:Molina Montenegro Marco A*; Torres Diaz Cristian; Carrasco Urra Fernando; Gonzalez Silvestre Leticia A; Gianoli Ernesto
来源:Gayana - Botanica, 2012, 69(1): 152-160.
DOI:10.4067/S0717-66432012000100015

摘要

Antarctica is characterized by extreme environmental conditions, which limit the establishment of vascular plants. These environmental conditions include low temperatures, short growing season and shortage of water and nutrients. Low water availability has been suggested as the main constraint to successful establishment, because it adversely affects the reproductive and physiological responses of plants. Colobanthus quitensis (Kunth) Bartl. (Caryophyllaceae) is one of the two native vascular plants that inhabit the Maritime Antarctic and its physiological performance and recruitment have been shown to be negatively affected by soil water stress in the Antarctica. Phenotypic plasticity and local adaptation would be two of the main strategies of C. quitensis to cope with adverse environmental conditions prevailing in the Antarctic continent. It has been suggested that, under a future climate change scenario, water availability will increase by 30-40%, improving the conditions for plant establishment. In this study we evaluated in a common garden experiment, conducted in growth chambers, the morpho-physiological plasticity and reproductive effort in C. quitensis individuals from two sites located in the Shetland Islands, under a simulated scenario of climate change (40% increase in water availability) and under the current situation (water availability recorded in the sites of origin). Overall, individuals of C. quitensis of both sites showed a plastic response, increasing the photochemical efficiency, leaf width and length and reproductive effort under increased water availability. Plasticity was greater in those individuals from the more arid site as compared to con-specifics from a mesic site. If current climate change patterns are maintained, abiotic conditions could become more favorable for C. quitensis, improving ecophysiological performance and allowing the spread of its range in the Antarctic.

  • 出版日期2012