Parentage analysis in pear cultivars characterized by SSR markers

Abstract

Parentage of 14 pear cultivars, including 8 cultivars derived from intraspecific crosses and 6 from interspecific crosses, was analyzed using 20 SSR (simple sequence repeat) markers. In 10 out of 14 cultivars, the parent-offspring relationships were reconfirmed because the hybrids inherited SSR alleles from their parents without any discrepancy. There were 4 questionable parent-offspring relationships with respect to 7 or more SSR loci. 'Housui' (syn. 'Hosui') is not an offspring from a cross of 'Ri-14' X 'Yakumo' because of discrepancies at 7 loci. Likewise, 'Chojuro' and 'Nijisseiki' could not be confirmed as parents of 'Tanzawa' because of discrepancies at 9 loci. 'Max Red Bartlett' was reconfirmed as a parent of 'Oharabeni' because all SSR loci matched. 'Okusankichi' was not its parent because of discrepancies at 7 loci. Our analyses revealed that 'Le Conte' is not a parent of 'Ninomiya', whereas 'Chojuro' is. In this study, 20 SSR markers were effectively utilized to determine parentage of Japanese pear, and 15 SSR markers could be utilized for interspecific Pyrus hybrids.