The Chinese pear(Pyrus spp.)exhibits typical gametophytic self-incompatibility(GSI),which inhibits self-crossing and promotes out-crossing,similar to other fruit species in the Rosaceae family.Thus,S-compatible cultivars are required in pear orchards to ensure success-ful pollination and stable yields.In this study,84 native Chinese pear accessions were genotyped by allele-specific PCR using one pair allele consensus primers and 29 pairs of S-allele-specific primers that were designed in this study.After cloning and sequencing the PCR products,the S-genotypes of all 84 pear accessions,including wild and cultivated accessions,were determined.The reported 34 S-alleles and a novel S-allele were isolated from these pear accessions.These S-alleles were expressed specifically in the style.Sequence analysis identified that six pear cultivars originated in China shared the same S-RNases with P.communis(Pc).These findings supported the hypothesis that oriental and occidental Pyrus spp.may share the same pool of alleles at the S-locus.A novel S-RNase was isolated in'Putiandouli','Daguoshanli','Yunhongli 1',and'Dianli'and deposited as S67-RNase under accession number MT773568.Furthermore,the deduced amino acid sequences exhibited high similarity(99.56％)to S32-RNase in Malus.The high similarity between S-RNase in Pyrus and Malus indicated that the existence of S-RNase could have predated speciation between Pyrus and Malus.Furthermore,S-allele information was rearranged in Asian and European pears to pro-vide information for selecting the best pollinator for widely cultivated pear cultivars in China.This information is useful for pear production,cross-breeding,and understanding the mechanism of the self-incompatibility reaction.

Min He;Lufei Li;Ying Xu;Jianxin Mu;Zhihua Xie;Chao Gu;Shaoling Zhang

Pear Engineering and Technology Research Center,State Key Laboratory of Crop Genetics and Germplasm Enhancement,Nanjing Agricultural University,Nanjing 210095,China

园艺学报（英文版）

[1]Min He;Lufei Li;Ying Xu;Jianxin Mu;Zhihua Xie;Chao Gu;Shaoling Zhang-.Identification of S-genotypes and a novel S-RNase in 84 native Chinese pear accessions)[J].园艺学报（英文版）,2022(06):713-726

gametophytic,RNases,occidental,Putiandouli,Daguoshanli,Yunhongli,Dianli,S67,MT773568

Identification,genotypes,novel,native,Chinese,accessions,Pyrus,spp,exhibits,typical,self,incompatibility,GSI,which,inhibits,crossing,promotes,out,other,fruit,species,Rosaceae,family,Thus,compatible,cultivars,required,orchards,ensure,success,pollination,stable,yields,In,this,study,were,genotyped,by,using,one,consensus,primers,pairs,that,designed,After,cloning,sequencing,products,including,wild,cultivated,determined,reported,alleles,isolated,from,these,These,expressed,specifically,style,Sequence,analysis,identified,six,originated,China,shared,same,communis,Pc,findings,supported,hypothesis,oriental,may,pool,locus,was,deposited,number,Furthermore,deduced,amino,acid,sequences,exhibited,high,similarity,S32,Malus,between,indicated,existence,could,have,predated,speciation,information,rearranged,Asian,European,pears,vide,selecting,best,pollinator,widely,This,useful,production,breeding,understanding,mechanism,reaction

0.474331