The principle investigators will study the risk of local extinction for Illinois populations of American ginseng, Panax quinquefolium, a commercially valuable, heavily harvested plant species. American ginseng suffers severe reductions in population size due to destruction of its forest habitat and harvesting pressure. Population biology theory predicts decreased survival probability for small populations of organisms due to potential genetic problems (i.e., decreased genetic diversity) and demographic problems (i.e., low reproductive success). Consequently, the goals of this project are (1) to identify the location and size of remaining populations of American ginseng in Illinois, (2) to monitor demographic and fitness parameters, such as number of seedlings and seeds in a subset of eight populations, (3) to determine the genetic diversity within and between a subset of twenty populations, and (4) predict survival probabilities for populations of different sizes. Genetic diversity will be assessed for proteins and DNA.
Despite predictions that small populations suffer increased extinction risks, native species of economic value, such as ginseng and Echinacea are regulated without vital genetic and demographic information on natural populations. Life history characteristics of P. quinquefolium, such as self-pollination and limited seed dispersal, make it vulnerable to loss of genetic diversity and decreased fitness. Therefore, P. quinquefolium is an important species for which to combine basic genetic and demographic information to assess viability of natural populations.
