REPRODUCTIVE-BIOLOGY OF ASCLEPIAS-SYRIACA POPULATIONS IN ZAHORSKA NIZINA LOWLAND .2. NOTES ON VIABILITY SEEDS GERMINATION AND SEEDLING DEVELOPMENT

Asclepias syriaca reproduces by adventitious roots and by seeds. In Slovak populations a high viability as well seedling reqruitment was found. The effect of stratification on seed germination, and seedling emergence under natural conditions was studied. Attention was concentrated on strategy of the species in selected localities causes of high mortality of young plants, and ability for establishment of new clones.