| Abstract Detail
Ecological Section Zaya, David N. [1], Leicht-Young, Stacey A. [2], Pavlovic, Noel B. [3], Ashley, MV [4]. Invasion and Hybridization as Potential Mechanisms for Cryptic Extinction: A Bittersweet (Celastrus spp.) Story. The threat that introduced species pose to native species through hybridization has only recently gained attention. Hybridization can be a serious threat to ‘pure’ lines of a native species, leading to rapid extirpation or extinction. The introduced oriental bittersweet (Celastrus orbiculatus, Celastraceae) is an aggressive and rapidly spreading vine that kills native vegetation by shading, girdling, or weighing down trees. Oriental bittersweet may also threaten native American bittersweet (C. scandens) through hybridization. Manipulative hand-crosses have shown the two Celastrus species can hybridize, but little is known about the prevalence and characteristics of hybrids in the wild. Uncertainty regarding the prevalence of hybrids is exacerbated by the fact that the two species are difficult to distinguish in the absence of reproductive structures. We have developed molecular markers (DNA microsatellites) that unambiguously distinguish the two species and their hybrids, regardless of season or plant reproductive stage. Leaf collections were taken from reproductive bittersweet individuals across the eastern United States. Analyses using principal components analysis and Bayesian clustering techniques show that established hybrids do exist in the wild, but are not prevalent. Genetic analysis of hybrids using a maternally inherited marker (chloroplast RFLP) and microsatellite genotypes of seedlings collected from pistillate individuals of both species provide strong evidence for asymmetric hybridization; oriental bittersweet almost always acts as the pollen donor in interspecific crosses. Asymmetric interspecific pollen flow is likely due to greater male fecundity in the invasive vine. As the invasion of oriental bittersweet progresses in the eastern United States, pure lines of American bittersweet will likely be threatened due to asymmetric hybridization. Broader Impacts:
Log in to add this item to your schedule
1 - University of Illinois Chicago, Department of Biological Sciences, M/C 066, 845 W Taylor St., Chicago, IL, 60607, USA 2 - U. S. Geological Survey, 1100 N. Mineral Springs Rd., Porter, IN, 46304 3 - U.S. Geological Survey, 1100 N. Mineral Springs Road, Porter, IN, 46304 4 - University of Illinois at Chicago, Biological Sciences, UIC Biological Sciences (M/C 066), 845 W. Taylor, Chicago, IL, 60607, USA
Keywords: hybridization biological invasion Celastrus orbiculatus Celastrus scandens Microsatellites (SSRs).
Presentation Type: Oral Paper:Papers for Sections Session: 24 Location: 555B/Convention Center Date: Tuesday, August 3rd, 2010 Time: 9:00 AM Number: 24005 Abstract ID:484 |