Comparisons of within-population genetic variation in sexual and agamospermousAmelanchier (Rosaceae) using RAPD markers

We compared genetic variation of sexualAmelanchier bartramiana and facultatively agamospermous (asexually seed-producing)A. laevis at one site where the two species are sympatric. We analyzed 77 random amplified polymorphic DNA (RAPD) markers in 29A. bartramiana individuals and 76 RAPD markers in 31A. laevis individuals. The two species do not differ significantly in mean genetic variation. However, 22.4% of genetic similarity values betweenA. laevis individuals exceed the highest value ofA. bartramiana and may represent the effect of agamospermy. Variation withinA. laevis may be the result of sexuality, hybridization, polyploidy, and other factors.