Hawthorns (Crataegus) are used for horticultural and medicinal purposes. They can be used as a rootstock for grafting. They are graft compatible with Mespilus L. (medlar), pear (Pyrus L.), and quince (Cydonia Mill.). Moreover, they are traditionally used for their cardio-protective benefits and antioxidative potential. The pharmacological importance of Crataegus is attributed mainly to components such as flavonoids, procyanidin, aromatic acid, and cardiotonic amines. In the present investigation, 70 accessions of Crataegus monogyna Jacq. originating from natural populations in the Kashan region, Iran, were characterized using a set of 49 morphological traits. An analysis of variance showed a high variability in the evaluated accessions and significant differences were found between them for most of traits measured. Results from simple correlation analysis showed significant positive and negative correlations among certain important characteristics. Leaf length was positively and significantly correlated with leaf width; fruit weight was positively and significantly correlated with fruit length and width. Fruit flesh weight showed high positive correlations with fruit width and weight and negative correlation with seed number. A principal component analysis showed high discrimination capabilities of variables measured. Cluster analysis revealed a grouping of accessions in three major clusters, where clusters with large number of accessions contained sub-clusters. The present findings indicated that the studied hawthorn germplasm must be conserved as valuable genetic resources.
