Short Communication

Alpine Botany

, Volume 121, Issue 2, pp 123-127

Open Access This content is freely available online to anyone, anywhere at any time.

No evidence for a role of competitive capabilities of adults in causing habitat segregation of diploid and hexaploid Senecio carniolicus (Asteracaeae)

  • Karl HülberAffiliated withVienna Institute for Nature Conservation & AnalysesDepartment of Conservation Biology Vegetation and Landscape Ecology, University of Vienna Email author 
  • , Andreas BergerAffiliated withDepartment of Systematic and Evolutionary Botany, University of Vienna
  • , Christian GilliAffiliated withDepartment of Systematic and Evolutionary Botany, University of Vienna
  • , Markus HofbauerAffiliated withDepartment of Systematic and Evolutionary Botany, University of Vienna
  • , Monika PatekAffiliated withDepartment of Conservation Biology Vegetation and Landscape Ecology, University of Vienna
  • , Gerald M. SchneeweissAffiliated withDepartment of Systematic and Evolutionary Botany, University of Vienna

Abstract

Hexaploid individuals of Senecio carniolicus (Asteraceae) predominantly occur in dense swards while diploids prevail in open vegetation. We test whether this habitat segregation is due to differential responses to competition. Linear regression models were used to relate biomass and maximum leaf length of adults to vegetation cover within radii of 20 cm around target individuals. Biomass differed between ploidy levels, but was independent from vegetation cover in both cytotypes. Maximum leaf length of diploids increased with vegetation cover, but remained constant in hexaploids. This suggests that at the adult stage diploids respond to increasing competition by changes in plant architecture rather than changes in resource utilization, while hexaploids are unaffected by competition. Consequently, other factors, such as competitive interactions at earlier life stages, likely are responsible for habitat segregation of diploid and hexaploid S. carniolicus.

Keywords

Polyploidy Competition Alpine plants Biomass Vegetation cover