Identification of 20 S-genotypes and cloning novel S-RNases in Pyrus Molecular mechanism and Genetic Characterization of self-compatibility in pears ‘Osa-Nijisseiki’ Mutational Mechanism of Self-compatible Pear Cultivar‘Jinzhuili’(Pyrusbretschneideri) Mutational Mechanism of Self-compatible Pear Cultivar‘Jinzhuili’(Pyrusbretschneideri) Identification of 20 S-genotypes and cloning novel S-RNases in Pyrus Identification of S-Genotypes of Pear Cultivars and Analyses of NucleotideSequences of S28-RNase and S30-RNase Identification of S-Genotypes of Pear Cultivars and Analyses of NucleotideSequences of S28-RNase and S30-RNase Molecular mechanism and Genetic Characterization of self-compatibility in pears ‘Osa-Nijisseiki’