Prunus arabica (Olivier) Meikle, an important genetic resource for breeding of almond: morphological and pomological characterizations

Phenotypic variation of 75 accessions of wild Prunus arabica (Olivier) Meikle species was assessed. There were significant variations among the accessions based on the characters recorded. The range of nut-related characters was as follows: nut length: 12.67-18.82 mm, nut width: 8.23-13.74 mm, nut thickness: 6.96-9.73 mm, and nut weight: 0.33-1.12 g. The range of kernel-related characters was as follows: kernel length: 9.74-15.31 mm, kernel width: 5.34-9.32 mm, kernel thickness: 3.51-5.98 mm, and kernel weight: 0.11-0.36 g. Flowering date ranged from late March to early April, and ripening date varied from late May to early July. Nut weight was positively correlated with dimensions of peduncle, petal, calyx, sepal, leaf, and nut. Principal component analysis (PCA) revealed 22 PCs which contributed 85.65% of total variance. The Ward dendrogram revealed the similarities and dissimilarities among the accessions in terms of the recorded characters and divided them into two main clusters. Considerable genetic diversity was observed among P. arabica accessions studied at morphological level, indicating rich and valuable plant materials for almond rootstock improvement. Wild P. arabica species is a potential source for transferring valuable resistances regarding its ability to withstand unfavorable environments.

Automated summary

Phenotypic variations were assessed among 75 accessions of wild Prunus arabica (Olivier) Meikle species. Significant differences were observed among the accessions based on recorded characters. The study revealed considerable genetic diversity at the morphological level, indicating the potential value of these wild P. arabica accessions for almond rootstock improvement.