A Biosystematic Study of Silphium Integrifolium Michaux (Compositae)

Author Institution: Biology Department, State University of New York, College at Oneonta, Oneonta, New York 13820, and Biology Department, Bowling Green State University, Bowling Green, Ohio 43403Cytological and chromatographic data indicate that Silphium integrifolium Michx. is a rather homogeneous group of plants. Cytological study shows good pairing during meiosis in interspecific and intraspecific hybrids. Two-dimensional paper chromatography indicates that the varieties of S. integrifolium are more similar to each other than they are to two related species, S. asperrimum and S. speciosum. The varieties of S. integrifolium are chromatographically homogeneous