Crataegus L. genus belongs to the Rosaceae family having beneficial effects on human health. In the present study, phenotypic diversity of Crataegus pentagyna and C. monogyna from northeastern parts of Iran was evaluated. The studied accessions of both species showed significant differences based on morphological and pomological characters measured. Leaf length ranged from 19.00 to 47.64mm in C. pentagyna and 19.77 to 53.11mm in C. monogyna. Ten-fruits weight varied from 2.75 to 7.80 g in C. pentagyna and 3.08 to 12.80 g in C. monogyna. The number of seeds was 3 to 5 in C. pentagyna, while only one seed was observed in the fruits of all the C. monogyna accessions. Fruit weight was positively correlated with leaf and fruit dimensions, while it was negatively correlated with fruit density. Principal component analysis (PCA) revealed that fruit traits contributed the most to accession diversity and followed by leaf traits. The accessions were grouped into two major clusters and separated based on their related species by unweighted pair group method with arithmetic mean (UPGMA) dendrogram. Regarding the important characters influencing fruit yield and quality, 13 accessions of C. monogyna and also five accessions of C. pentagyna were superior and could be used as a parent in breeding programs and also might be singled out directly for cultivation. The current study provided data that could be used to enhance the conservation and reasonable utilization of the remarkable wild Crataegus.
