Determination of the extent of hybridization between the threatened Hibiscus dasycalyx, Hibiscus laevis, and Hibiscus moscheutos using ISSR genetic markers

East Texas is home to several native Hibiscus species, including Hibiscus dasycalyx , Hibiscus laevis, and Hibiscus moscheutos . These species are herbaceous perennials that live in wetland conditions. Of the three morphologically distinct species, H. dasycalyx has been listed as threatened by the US Fish and Wildlife Service. Before restoration can occur, the gene flow and level of hybridization with the other two species must be determined in its native habitat. Previous investigations in our laboratory of these species have suggested that the Hibiscus dasycalyx is an individual species with little to no hybridization, however, a more comprehensive analysis is needed using a larger sampling set. The objective of this study is to identify species specific Intersimple Sequence Repeat (ISSR) markers for Hibiscus dasycalyx, H. laevis and H. moscheutos so that these markers could be used for tracking the extent of hybridization that occurs between the three species as well as the gene flow of H. dasycalyx . Genomic DNA was extracted and PCR amplified using ISSR primers (Wolfe,1998). PCR products were separated on an ALF sequencer to detect polymorphisms between the three Hibiscus species. Population analysis software was used to determine the gene flow and extent of hybridization between H. dasycalyx , H. laevis and H. moscheutos .