Application of random amplified polymorphic DNA and inter-simple sequence repeat markers in the genus Crataegus

Hawthorn (Crataegus spp.) has a long history as an ornamental and a source of medicine. We report the use of random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers to determine genetic relationships in the genus Crataegus. Twenty-eight accessions, including eight species (Crataegus pinnatifida, Crataegus bretschneideri, Crataegus maximowiczii, Crataegus kansuensis, Crataegus altaica, Crataegus songarica, Crataegus dahurica and Crataegus sanguinea) and two botanical varieties (C. pinnatifida var. major and C. maximowiczii var. ninganensis) were analysed. Twelve RAPD primers reproducibly and strongly amplified 128 fragments of which 116 were polymorphic; similarly, 13 ISSR primers generated 127 products of which 119 were polymorphic. Dendrograms based On unweighted pair group method with arithmetic average analysis were constructed from both the RAPD and the ISSR data. Similarity coefficient based on RAPD and ISSR markers ranged from 0.22 to 0.98 and 0.23 to 0.98, respectively. The range in similarity coefficient indicated that the genus has a high level of genetic diversity. The Mantel test on the similarity matrices produced by RAM and ISSR markers gave r = 0.86, showing high correlation between RAPD and ISSR markers in their ability to detect genetic relationships between Crataegus accessions. RAPD and ISSR appear to be reliable methods for the analysis of genetic relationships among hawthorns.