Martin Vojík1,2, Martina Kadlecová1, Josef Kutlvašr1,2, Kateřina Berchová-Bímová1 and Jan Pergl2
1Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Praha – Suchdol, 165 00, Czech Republic
2Institute of Botany, Department of Invasion Ecology, The Czech Academy of Sciences, CZ-252 43, Průhonice, Czech Republic
Public parks and private gardens are sources of new potentially invasive plants, escaping from ornamental garden beds, lawns and hedges. The majority of studies are focused on invasions from plantings in mesic habitats via traditional spreading vectors (transport, watercourses, railways, etc.). Invasions in dry semi-natural and natural habitats are largely overlooked, even though semi-natural dry grasslands are often directly connected with gardens and plantings in warmer areas of Central Europe. The identification of potentially invasive xerophytes and description of their ecology can help prevent their further spread.
The objective of our project is a comprehensive study of the potentially invasive alien species, Stachys byzantina and Lychnis coronaria. Both species are escaping from cultivations and form stands that reduce the diversity in the herb layer of ornamental plantations and, after escaping, also in their close surroundings. It is therefore possible that these species with a high invasive potential (i.e. escape from cultivation was recorded throughout the Czech Republic) can continually reach natural biotopes and create viable naturalised populations with high impacts on the environment.
The study is aimed at the identification of (i) reproductive traits rate and mode of spread, germination of seeds, generative reproduction, vegetative regeneration and growth rate, and (ii) cytological variability of the plants using flow cytometry (ploidy levels and genome size).
Based on the obtained information, we want to consider the ability to invade dry semi-natural and natural habitats for the model species. Our preliminary results based on diploid populations show that seed germination of L. coronaria is very high (98%) and germination of S. byzantina is about 40%. Seeds of both study species are resistant to low temperature (up to -16°C) and both species have fast growth speeds with vegetative spread via forming daughter shoots.