Folia Geobotanica 40: 385–405, 2005 MORPHOMETRIC AND GENETIC DIVERGENCE AMONG POPULATIONS OF NEOTINEA USTULATA (ORCHIDACEAE) WITH DIFFERENT FLOWERING PHENOLOGIES Milena Haraštová-Sobotková1), Jana Jersáková1,2), Pavel Kindlmann1,2) & Ladislav Èurn3) 1) Faculty of Biological Sciences, University of South Bohemia, Branišovská 31, CZ-370 05 Èeské Budìjovice, Czech Republic; fax +420 385 310 366, e-mail
[email protected] 2) Institute of Landscape Ecology, Academy of Sciences of the Czech Republic, Na Sádkách 7, CZ-370 05 Èeské Budìjovice, Czech Republic 3) Faculty of Agriculture, University of South Bohemia, Studentská 13, CZ-370 05 Èeské Budìjovice, Czech Republic Abstract: The terrestrial orchid species Neotinea ustulata has recently been split into two subspecies, differing remarkably in their flowering time, but only slightly in morphological characteristics, which makes their taxonomic status uncertain. We have analyzed morphometric and genetic differences between the early- and late-flowering populations in Central Europe. Our results on morphology are ambiguous. Indirect gradient analysis has not shown a distinct separation of early- and late-flowering individuals in the ordination space. However, according to MANOVA, populations of early- and late-flowering plants can be distinguished by plant height, leaf length, numbers of basal (rosette) and stem leaves and even better by certain ratios of these numbers. All genetic analyses, on the other hand, are definite and consistently distinguish two groups. Random amplified polymorphic DNA (RAPD) markers have shown that the early- and late-flowering populations differ significantly from one another. Principal coordinate analysis (PCoA) based on presence/absence matrix of RAPD bands separated the two groups, implying that the difference in flowering phenology could form an effective barrier to gene exchange.