Deciphering the Population Genetic Structure of Eastern Leatherwood (\u3ci\u3eDirca palustris\u3c/i\u3e) Using ISSR- Analysis

Using intersimple sequence repeat (ISSR) analysis, the goal of this study was to determine the relationship between geographic and genetic distance within a population of the shrub, Dirca palustris, located in Central Minnesota. We formulated hypotheses based on levels of observed geographic structure: (1) Dirca subpopulations separated by greater than four kilometers will exhibit greater genetic differentiation than is observed among closer subpopulations; (2) Dirca subpopulations separated by less than four kilometers will exhibit greater genetic differentiation than is observed among discrete plant clusters within subpopulations; and (3) discrete clusters within a subpopulation will produce genetic patterns enabling us to identify potential parent-offspring relationships. On spatial scales less than seven kilometers Dirca does not exhibit significant geographic structuring by genetics. Parent-offspring relationships within a plant cluster were not observed. The results suggest that factors such as population history, seed disperser and pollinator ranges, local adaptive pressures, or clonal regeneration may play a greater role in Dirca population structure