Identification of Self- incompatibility Alleles in Some Almond Genotypes by Degenerate S-RNase Primers


1 Department of Horticultural Sciences, Faculty of Agriculture, Shahed University, Tehran, Iran

2 Department of Horticultural Sciences, Faculty of Agriculture, University of Mohaghegh Ardabili, Ardabil, Iran


The almond, Prunus dulcis Miller which belongs to Rosaceae family, is one of the most important commercial and oldest cultivated tree nut crops. Almonds are classified as a ‘nut’ in which the edible seed is the commercial product. Therefore, pollination and fertilization are necessary in almond. The characteristic of cultivated almond to express gametophytic self- incompatibility discourages self-fertilization and favors cross pollination. Genetic control of pollen-pistil self-incompatibility is through a single gene (S) which exists in a series of alleles S1 to Sx. Compatibility of pollen-pistil in almond is an important consideration in planning crosses in breeding program and in choosing pollinizers for orchard planting. Identification of self-(in) compatibility in almond carried out by molecular and controlled pollination methods. In this study, identification of S-alleles in 37 Iranian almond cultivars and genotypes was carried out by PCR method with using degenerate primers of EM-PC3consRDEMPC2cons FD, PaconsI-Fand EM-PC1consRD. In this way the size of S -alleles were estimated based on bands which amplified with second intron. The results confirmed self-incompatibility in cultivars and most genotypes. However, the Sf-like allele (in size) was observed in A9 and A36 genotypes. If these results are confirmed by sequencing the Sf allele, it will be first time to identify self-compatible genotype in Iranian almond genotypes.