Inter-simple sequence repeat (ISSR) variation in populations of the cutgrass Leersia hexandra

Genetic variability of a perennial clonal aquatic weed Leersia hexandra was estimated by the ISSR assay. A total of 225 L. hexandra individuals collected from 10 populations in China were analyzed. The 12 used ISSR primers generated 175 bands, with an average of 14.6 per primer. The average values of percentage of polymorphic bands (PPB), effective number of alleles (Ae), and gene diversity (He) in these populations were 49.7%, 1.258, and 0.154, respectively, indicating a considerable genetic diversity in this species. Significant genetic differentiation was found among populations with the major genetic variability within populations based on Nei's genetic diversity analysis (Gst = 0.417) and AMOVA (40.1%). Genetic variation is independent of geographical distance. This pattern of genetic variation may be associated with reproductive mode of its mixed breeding systems although mainly through vegetative propagation.