Reproductive biology and floral variation in the endangered Braya longii and threatened B. fernaldii (Brassicaceae): Implications for conservation management of rare plants

The closely related, endangered Braya longii and threatened Braya fernaldii (Brassicaceae) are endemic to the limestone barrens of the Great Northern Peninsula of Newfoundland. This project determines potential breeding systems, levels of population differentiation, potential hybridization between these species and implications for conservation management. Morphological species differences are also summarized to ensure proper identification of new populations. Results indicate field identification using only single morphological characters is insufficient to unambiguously identify species. Both species were found to be primarily autogamous but B. longii has a greater potential for outcrossing than B. fernaldii. Cleistogamy was found to occur within some populations of B. fernaldii, but not in B. longii. Evidence of population differentiation in floral morphology was found for both species and potential hybridization was indicated by floral morphology and hand-pollinations. The results of this study provide guidance for potential conservation management tools and must be addressed before reintroduction and population restoration are implemented.