INVESTIGATIONS INTO THE EVOLUTIONARY HISTORY OF THE POLYPLOID COMPLEXES IN ANTENNARIA (ASTERACEAE, INULEAE) .1. INVESTIGATIONS INTO THE EVOLUTIONARY HISTORY OF THE POLYPLOID COMPLEX ANTENNARIA-NEODIOICA (ASTERACEAE, INULEAE)

The Antennaria neodioica polyploid agamic complex is a polymorphic species occurring across North America mainly north of the terminal margin of the Wisconsin glacier. This taxonomically difficult group has recently been treated as consisting of the four subspecies A. neodioica subsp. canadensis, subsp. howellii, subsp. neodioica, and subsp. petaloidea. The A. neodioica agamic complex has been considered of hybrid origin with several sexual diploid species constituting its parentage. Crosses were made among five sexual diploid species of Antennaria morphologically similar to A. neodioica s.l., in an attempt to discover its origins. Representative specimens of the five diploid species, A. neodioica s.l., and the synthetic interspecific F1 hybrids were subjected to various analyses including principal component analysis, cluster (UPGMA), and discriminant analyses. Results suggest that the A. neodioica complex is of multiple hybrid origin involving the four diploid species A. neglecta, A. plantaginifolia; A. racemosa, and A. virginica. Because A. neodioica is the result of diverse origin it is more desirable to consider the agamic complex as a separate, distinct species from its sexual diploid relatives. Several morphological characters in the diploid species were determined to be polygenically inherited.