Alpine Botany

, Volume 121, Issue 1, pp 37–47

Differentiation in morphology and flowering phenology between two Campanulathyrsoides L. subspecies

Authors

    • Institute of BotanyUniversity of Basel
  • Patrick Kuss
    • Institute of Plant SciencesUniversity of Bern
  • Jürg Stöcklin
    • Institute of BotanyUniversity of Basel
Original Paper

DOI: 10.1007/s00035-011-0087-3

Cite this article as:
Scheepens, J.F., Kuss, P. & Stöcklin, J. Alp Botany (2011) 121: 37. doi:10.1007/s00035-011-0087-3

Abstract

Subspecies are usually characterised by sets of morphological discontinuities. By means of common garden experiments, we investigated genetic differentiation in morphological and phenological traits in two geographically disjunct subspecies of Campanula thyrsoides L., i.e. subsp. thyrsoides (=C.* thyrsoides) occurring in the European Alps and Jura Mountains, and subsp. carniolica (=C.* carniolica) occurring in the Southeastern Alps and the Dinaric Arc. Nine out of 16 investigated traits were significantly different between C.* thyrsoides and C.* carniolica. For C.* carniolica inflorescence length was 1.4×, and above-ground biomass 2.7× higher, while flower density was significantly lower. Campanula* carniolica also showed delayed flowering and flower development from bottom to top as compared to C.* thyrsoides which flowered from top to bottom. The inflorescence growth was indeterminate and flowering took several weeks in C.* carniolica, whereas C.* thyrsoides showed determinate flowering, rapidly opening all flowers within a few days. This differentiation in flowering phenology is likely to be adaptive. The submediterranean climate favours indeterminate flowering in C.* carniolica, allowing ongoing growth of the inflorescence throughout the long summer until environmental conditions worsen, whereas determinate and early flowering in C.* thyrsoides is favourable in the short growing season in the high Alps where seed production must be secured before temperature drops. Glacial survival in refugia with different climates (alpine vs. submediterranean) may have caused this regional differentiation.

Keywords

Campanula thyrsoides subsp. carniolicaCommon gardenDeterminate floweringEuropean AlpsGlacial history

Supplementary material

35_2011_87_MOESM1_ESM.doc (68 kb)
Supplementary material 1 (DOC 68 kb)

Copyright information

© Swiss Botanical Society 2011