Identification of S-genotypes of four cultivars and sequence analyses of S31-RNase in Eriobotrya Lindl.

【Objective】The objective of this study is to determine the S-genotypes of four Chinese loquat cultivars,including Eriobotrya japonica‘Guifei',E. japonica‘Huangmi',E. japonica‘Zaohong',E.japonica‘Ruantiaobaisha',to provide the scientific basis for pollinizer selection in cultivation and parents selection in breeding.【Method】Using two pairs of primers which designed from conserved sequences of known apple S-RNases,PCR amplification was carried out for genomic DNAs of four Chinese loquat cultivars. Then after cloning and sequencing of PCR products,and the homology blast and sequence analysis of these amplified fragments were carried out by Blast and Bioedit.【Result】In this study,four S alleles were separated from the four Chinese loquat cultivars,namely S2,S5,S6 and S31,and the S31 was a new S-gene cloned from E. japonica‘Ruantiaobaisha'cultivar and its accession number was KC131133 in Gene Bank. Same as the apple S-RNases,the alignment of these cloned S-RNases had one identified hypervariable region(HV) and four conserved regions(C2,C3,RC4 and C5).【Conclusion】The S-genotypes of the four tested cultivars were identified as follows: E. japonica‘Guifei'(S2- S6),E. japonica‘Huangmi'(S2-S5),E. japonica‘Zaohong'(S5-S6),E. japonica‘Ruantiaobaisha'(S6-S31).