Hybridization as a key to understanding the evolution of the genus Dactylorhiza

Orchids, comprising almost one tenth of plant species, are a complicated group in terms of botanical research due to their specific life cycle and frequent hybridization. One of the particularly biosystematically difficult representatives of orchids is the genus Dactylorhiza, which is characteristic for the occurrence of a whole range of poorly identifiable hybrids and hybridogenic species. Hybrid plants, arising mainly between the basic species D. incarnata and D. fuchsii/maculata agg., exist here at the level of primary hybrids, especially in hybrid zones, and hybridogenic species (most common D. majalis). Hybridization in the genus Dactylorhiza was studied in a thesis to determine the direction of hybridization, whether it can occur at the homoploid or heteroploid level, and whether backcrossing of hybridogenic species occurs. The plants were studied both in natural locations and in a hybridization experiment using in vitro cultivation and flow cytometry. Dactylorhiza maculata was identified as the species with the most variable offspring (relative genome size and occurrence of unreduced gametes). All studied species (including the difficult-to-cultivate D. maculata) except D. incarnata were successfully cultivated. I found that that hybridization can occur bidirectionally at the homoploid and...