Reciprocal transplantations reveal strong niche differentiation among ploidy-differentiated species of the Senecio carniolicus aggregate (Asteraceae) in the easternmost Alps

Phenotypic changes conferred by polyploidisation likely alter the ecological niche of polyploids, coming along with differences in performance compared to their diploid ancestors. However, it is largely unknown, whether these performance differences remain constant during the life history of plants. Diploid S. noricus, tetraploid S. disjunctus and hexaploid S. carniolicus s. str. of the autopolyploid species-complex of Senecio carniolicus (Asteraceae) from the easternmost Alps were reciprocally transplanted to address the following questions: Are there differences in species performances indicating niche differentiation? If so, does the resident or the higher-ploid species – which is taller-growing and possibly more tolerant against challenging abiotic and biotic conditions – show higher performance? Are performance differences consistent between early and late life history stages? Our data suggest that the hierarchy of species performance depends on the life-history stage. For early li...