| A. Our lab investigates plant species of economic importance and native species that perform important ecosystem services. Below are some examples of our current projects:
Developing the next generation of biofuels for the SE US
Energy security, oil prices and growing demands for fuel have catalyzed the search for alternative economically viable and environmentally sustainable energy sources. Using various ecological and molecular approaches, we investigate the potential of a natural triploid hybrid Miscanthus giganteus (grass native to Japan) to become the most suitable next generation energy crop in the southeastern North America while contributing to restoration of degraded soils and long-term carbon sequestration (thus mitigating greenhouse emissions and climate change).
Understanding relationships between evolutionary history of sea oats (Uniola paniculata) and adaptations to environmental conditions.
Coastal dunes, after beaches, are second in line of defense to protect the land from sea. The principal native dune-forming vegetation along the southeastern North American coast is sea oats, Uniola paniculata (Poaceae). The overarching objective is to provide new tools and science-based knowledge in designing restoration strategies, conservation and sustainable management of coastal habitats. So far, we used chloroplast DNA variation to describe phylogenetic relationships among intraspecific maternal lineages and their geographic distribution. Overall pattern is in concordance with previously reported animal studies (with Atlantic/Gulf split). We are now investigating whether distribution of adaptive traits in this species follow the same pattern, or whether adaptive traits follow their own evolution shaped by environmental conditions, regardless of its history.
Reconstruction of phylogeographic history and identification of wild populations of American ginseng, Panax quinquefolius, (Areliaceae).
American ginseng is one of the most heavily traded native medicinal plants in North America. We use phylogeographic approaches to describe its intraspecific history and in collaboration with the USGS lab in West Virginia, we will analyze genetic structure of this species using both, cpDNA and nuclear markers. This research will inform formulating conservation strategies and management of this species by the US Fish and Wildlife Service.
Liatris helleri vs. Liatris turgida: are they the same species?
Liatris helleri is a threatened perennial, endemic to only nine populations in Western North Carolina. The primary objective of this study is to investigate a hypothesis that L. helleri and L. turgida (its more common and widespread congener) are the same species. This hypothesis has been recently proposed based on morphological characters. We are using molecular markers to test the hypothesis.
B. Much of my post-doctoral research was focused on the genetic consequences of tropical forest fragmentation. Tropical forests are being destroyed at an alarming rate; one of the results of this landscape level destruction is the production of fragments of the original forest. These fragments vary considerably in their size and in their degree of physical isolation. The majority of this research occurred in the tropical dry forest of Guanacaste Province in Costa Rica. The chief study species is Enterolobium cyclocarpum, the Guanacaste tree. Enterolobium cyclocarpum is an insect-pollinated mimosoid legume, a dominant tree in the drier regions of Central America. Our research team investigated pollen-mediated gene movement in relatively undisturbed forests in natural settings versus heavily disturbed, human-modified landscapes, as well as the role that isolated individuals play in the breeding populations of this species. We also conducted analyses of spatial organization of genetic variation at the micro-geographic scale (within a single population).
C. The goal of my PhD thesis was to examine seed and pollen mediated gene flow in Trillium cuneatum populations over a large temporal and spatial scale. I used various molecular and analytical approaches to infer recent evolutionary and glacial history of this species. For instance, variation in chloroplast DNA sequences revealed that the geographic range of this species is subdivided into two maternal lineages (eastern and western), a pattern that has been previously reported in several animal studies. The data also suggest that at least some populations most likely survived the last glacial episode in small isolated pockets in the Southern Appalachian Mountains. I used combination of fine-scale genetic structure analysis, clonal reproduction and pollen movement analysis (using TwoGener) to understand consequences of habitat fragmentation on distribution of genetic diversity. We documented differences in vegetative reproduction between Piedmont and mountain habitats, and differences in gene dispersal between fragmented and disturbed vs. continuous habitats.
One of my PhD dissertation chapters focused on federally endangered endemic species, Trillium reliquum. I used comparisons with its partially sympatric congener, T. cuneatum, to address questions related to its recent (~ 200-300 years) history and the consequences of habitat fragmentation.
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