Distribution and genetic diversity of the rare plant veratrum woodii (Liliales: Melanthiaceae) in Georgia: A peliminary study with AFLP fingerprint data
Veratrum woodii, a long-lived herbaceous perennial species, has a fragmented distribution with populations scattered in the southeastern and lower midwestern USA. In Georgia, the species has a protection status of rare. This preliminary study focused on verifying historic and/or unvouchered populations in Georgia and characterizing variation and genetic structure within and among all populations in the state. We analyzed AFLP (amplified fragment length polymorphism) data as dominantly inherited markers for 16 populations sampled from Georgia, Florida, and Missouri. Our results suggest that this species overall has relatively low levels of genetic diversity and that differentiation among populations is comparable to species with similar life history traits. Measures of genetic diversity, such as mean He, indicate that variation of populations has some partitioning between disjunct northern and southern Georgia (and Florida) populations. However, our analyses imply that watershed assignment, rather than geographic distance, provides a better explanation for variation and population structure. We hypothesize that southern relict populations in Georgia may have served as refugia during Pleistocene glaciations. We conclude that life-history characteristics, low levels of genetic variation, and suppression of ecological disturbance collectively jeopardize populations of Veratrum woodii in Georgia.