Variation in tolerance to drought among Scandinavian populations of Arabidopsis lyrata
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The ability to cope with water limitation influences plant distributions, and several plant traits have been interpreted as adaptations to drought stress. In Scandinavia, the perennial herb Arabidopsis lyrata occurs in open habitats that differ widely in climate and water availability in summer, suggesting differential selection on drought-related traits. We conducted two greenhouse experiments to examine differentiation in drought response traits among six Scandinavian populations, and to determine whether leaf trichomes confer protection against drought. We quantified tolerance to drought as fitness (survival and biomass of survivors) when exposed to drought relative to fitness under non-drought conditions. Two Swedish populations from shores along the Bothnian Bay had higher tolerance to drought than four riverbed populations from Norway. Under conditions of drought, the shore populations experienced less leaf damage compared to the riverbed populations, and their survival and biomass were less reduced relative to non-drought conditions. Across populations, tolerance to drought was positively related to leaf mass per area and negatively related to flowering propensity and proportion roots, but not related to plant size at the initiation of the drought treatment. In populations polymorphic for trichome production, trichome-producing plants were more tolerant to drought than glabrous plants. The results suggest that both leaf morphology and life-history traits contribute to differential drought response in natural populations of A. lyrata, and that this system offers excellent opportunities for examining the adaptive value and genetic basis of drought-related traits.
KeywordsAdaptive population differentiation Arabidopsis Drought stress Life history traits Local adaptation Resistance polymorphism Tolerance to drought Trichome production
We thank J. McKay for discussion, M. van Kleunen, H. Maherali and three anonymous reviewers for helpful comments on the manuscript, and L. Lehndal, L. Brockerhoff and F. Ågren for technical assistance. Financial support from the Swedish Research Council to NS and JÅ is acknowledged.
- Chaves MM, Maroco JP, Pereira JS (2003) Understanding plant responses to drought - from genes to the whole plant. Funct Plant Biol 30:239–264Google Scholar
- Ehleringer J (1984) Ecology and ecophysiology of leaf pubescence in North American desert plants. In: Rodriguez E, Healey PL, Mehta I (eds) Biology and chemistry of plant trichomes. Plenum Press, New York, pp 113–132Google Scholar
- Hultén E (1971) Atlas of distribution of vascular plants in NW Europe. Generalstabens litografiska anstalt, Stockholm, SwedenGoogle Scholar
- Huttunen P, Kärkkäinen K, Løe G, Rautio P, Ågren J (2010) Leaf trichome production and responses to defoliation and drought in Arabidopsis lyrata (Brassicaceae). Ann Bot Fenn 47:199–207Google Scholar
- Jalas J, Suominen J (1994) Atlas Florae Europeae. Distribution of vascular plants in Europe. Helsinki University Printing House, HelsinkiGoogle Scholar
- Körner C (2003) Alpine plant life. Functional plant ecology of high mountain ecosystems. Springer, HeidelbergGoogle Scholar
- Lambers H, Chapin FS, Pons TL (1998) Plant physiological ecology. Springer, New YorkGoogle Scholar
- Littell RC, Milliken GA, Stroup WW, Wolfinger RD (1996) SAS system for mixed models. SAS Institute, CaryGoogle Scholar
- Ludlow MM (1989) Strategies of response to water stress. In: Kreeb KH, Richter H, Hinckley TM (eds) Structural and functional responses to environmental stresses. SPB Academic, The Hague, pp 269–281Google Scholar
- Vergeer P, Kunin WE (2011) Life history variation in Arabidopsis lyrata across its range: effects of climate, population size and herbivory. Oikos. doi: 10.1111/j.1600-0706.2010.18944.x (in press)