Data from: New insights into floral morph variation in Passiflora incarnata L. (Passifloraceae) in Tennessee, U.S.A.
Cite this dataset
Krosnick, Shawn E. et al. (2018). Data from: New insights into floral morph variation in Passiflora incarnata L. (Passifloraceae) in Tennessee, U.S.A. [Dataset]. Dryad. https://doi.org/10.5061/dryad.8dm63
Passiflora incarnata is a functionally andromonoecious clonal wildflower, native to the southeastern United States, whose primary pollinator is the carpenter bee, Xylocopa virginica. While recent studies looking at reproductive ecology in P. incarnata have classified flowers as one of two morphs (male or hermaphroditic) based on stylar deflexion, preliminary field studies conducted in Tennessee indicated there were five distinct morphs present (three male, two hermaphroditic), supported by stylar deflexion, floral size, and pistil development. The present study sought to test the hypothesis that five distinct floral morphs are present in P. incarnata by sampling 13 floral characters, and to document variation in nectar constituents, volume, and concentration across the five morphs. Five well-established individual plants were examined at three sites in Cookeville, Tennessee. Two-factor permuted analysis of variance of 13 floral characteristics with floral morph and individual plants as factors suggested that morph:plant interactions explained 6%, individual plant explained 18%, and floral morph explained 36% of variation in floral characteristics. Nectar sampling indicated that all morphs produced nectar comprised exclusively of sucrose. Nectar volume generally increased with floral morph size, while nectar concentration decreased. NMDS analysis indicated that the five hypothesized morphs were supported as distinct, with substantial overlap between the two largest morphs (4a and 4b). The supported morphs are best distinguished by ovary width, ovary length, style length, and stigma width. These findings support a hypothesis that the morphs result from variation in developmental arrest during floral ontogeny. The ecological implications of the five morphs and nectar variation are considered for X. virginica with suggestions for additional studies.