XVI International Botanical Congess

The population genetic literature reveals a correlation between growth form and breeding system in monoecious carices. Rhizomatous species outcross due to genet intermingling - poorly differentiated populations (Gst=.16) exhibit high genetic diversity (He=.17). Caespitose species have less diversity (He=.04), which is apportioned among populations (Gst=.46), this is indicative of inbreeding. The caespitose, dioecious Carex scirpoidea (Cyperaceae) is an obligate outcrosser. Allozyme analysis conducted on five populations revealed moderate levels of diversity (He=.10), this was apportioned among individuals within populations (Gst=.10). All populations were in Hardy-Weinberg Equilibrium. These data agree with expectations and contribute to our understanding of the complex relationship between growth form and breeding system in Carex.