Does higher ploidy level increase the risk of invasion? A case study with two geo-cytotypes of Solidago gigantea Aiton (Asteraceae)

摘要: Understanding the role of genetics in biological invasions has become an important aspect for modern plant ecology. Many studies suggest that increased ploidy level benefits success invasive species, but basis this phenomenon is not fully understood. In its native, North American range, Solidago gigantea three geo-cytotypes comprising di-, tetra- and hexaploid populations, while Europe, where it highly invasive, S. stands are composed primarily tetraploid individuals. Our study investigates whether hexaploids can induce a greater risk invasion, due to their higher performance non-native as compared existing tetraploids range. We performed greenhouse common garden experiments along with microsatellite analyses test differences chromosome number origin species mean superior fitness introduced Genetic diversity was significantly native populations (AR = 6.04; Hₑ 0.7794), rather than 4.83; 0.6869). Furthermore, differentiation between moderate (ρST 0.1838), which also confirmed by clear segregation principal component analysis structure analyses, proving different genetic structure. contrast diversity, geo-cytotype better experiment, implying does always success. results do present risk, assessed when tetraploids, suggested previous studies. Nevertheless, introduction still undesirable structure, which, through hybridization, could give new drive invasion gigantea.