关键词: 柚, 单核苷酸多态性, 等位基因特异性PCR, 高分辨率熔解曲线分析, 基因分型

Abstract: Allele-specific PCR（AS-PCR）and high resolution melting analysis（HRMA）are two widely used SNP genotyping methods but no research has been done to compare them in terms of genotyping efficiency. In this study，16 pummelo cultivars and 8 pummelo hybrids were genotyped using AS-PCR and HRMA respectively on two different sets of 7 SNP loci. It was shown that both methods generated the same genotyping results in which 24 accessions were assigned into 22 genotypes. It was noteworthy that Hassaku and Red Hassaku were identical at all SNP loci，indicating both accessions should  have originated asexually from the same mother cultivar，as was the same case for the two Japanese summer orange cultivars，Beni Amanatsu and Kawano Natsudaidai. Interestingly，the early- and middle-season‘Zhenlong’pummelo cultivars possessed different genotypes，indicating clearly that they unlikely had the same origin as bud mutations as was thought before，and further analysis of HRMA results showed there is no direct hereditary relationship between them. Our results showed that both AS-PCR and HRMA were suitable methods for the identification of pummelo-related accessions. AS-PCR is a reliable and low-cost SNP genotyping method and easily accessible to ordinary laboratories though the method was found to be sensitive to changes in PCR conditions. HRMA is proven to be a reliable，quick，simple and high throughput SNP genotyping method；However，it uses special equipment and expensive reagents.

Key words: pummelo, single nucleotide polymorphism, allele specific-PCR, high resolution melting analysis, genotyping