Identification of S-genotypes of Pear Cultivars and Cloning of S₃₄-allele

Pear is a typical fruit tree of gametophytic self-incompatibility. Identifying the S-allele genotype of different pears is an important scientific foundation for arranging varieties for pollination and crossbreeding. It also establishes the foundation for inheriting and improving pear cultivars. On the basis of the reported primary structure of pear S₁-S₉, the primers PF and PR were designed. With the primers and leaf genomic DNA of cultivars Pyrus bretschneideri ‘Eli’ and Pyrus pyrifolia ‘Hakataao’, we used PCR-RFLP, cloning, sequencing and bioinformatic analysis to isolate and identify the two S-alleles of amplification segments with similar size. One of the S-alleles was newly identified and named S₃₄-allele. S-genotypes of the two cultivars were identified as Pyrus bretschneideri ‘Eli’ S₁₃S₃₄ and Pyrus pyrifolia ‘Hakataao’ S₂₂S₃₄.