Abstract

Large numbers of native plant cultivars are regularly imported for re-vegetation and restoration into the seminatural habitat of their wild cousins. It is hypothesized that cultivars and the wild cultivar hybrids are competitively superior to their wild relatives because cultivars are frequently selected for increased biomass output and may transfer these qualities into wild relatives through hybridization. Therefore, the introduction of such types could cause unexpected modifications to local plants. In this study, we investigated whether cultivars and artificially created intraspecific wild cultivar hybrids could produce a higher vegetative and generative biomass than their wild counterparts for two species that are frequently used in re-vegetation (Plantago lanceolata and Lotus corniculatus). A competitive experiment was carried out for that goal over the course of two growing seasons in a communal garden. Each plant type was either growing by itself, in pairwise combination with another plant type of a similar type, or in pairwise contact with another plant type [1]. When compared to the wild, hybrids produced more biomass than the wild in both of the research years, while cultivars of both species produced more biomass than the wild only in the first year. We come to the conclusion that cultivars and hybrids are competitively superior to their wild cousins because biomass production plays a significant role in determining fitness and competitive ability. Due to regional climatic circumstances, cultivars of both species, however, suffered significant fitness losses (almost full mortality in L. corniculatus). We come to the conclusion that cultivars are only effective competitors when they are not exposed to adverse environmental conditions. We consider hybrids to be strong competitors and believe they can outperform their wild counterparts, at least temporarily, because they appear to have inherited both the capacity to adapt to the local climatic conditions from their wild parents as well as the enhanced competitive strength from their cultivars.