Phenotypic and molecular characterization of new interspecific Japanese plum × apricot hybrids (plumcots)

Abstract

Japanese plum is a very important temperate tree fruit, ranking in the second position among the stone fruits, after peaches. In this species, there are very few self-compatible varieties and a lack of resistance to sharka disease (plum pox virus, PPV). In this context, interspecific crosses between Japanese plums and self-compatible, sharka-resistant apricot (Prunus armeniaca L.) cultivars have been performed in recent years to obtain resistant and self-compatible plumcots. The plumcot provides a new fruit typology combining the horticultural and market characteristics of these two Prunus species. In this work, new interspecific plumcots have been obtained and characterized. An initial screening of more than 600 seedlings was carried out for interspecific hybrid verification using Simple Sequence Repeat (SSR) markers. In addition, floral compatibility by S-allele genotyping and phenotypic characterization and PPV resistance evaluations in controlled conditions were performed in the interspecific genotypes. The results show some interspecific hybrids with the desired characteristics of self-compatibility alleles and sharka tolerance together with new fruit typologies with an attractive skin and flesh color and different valued organoleptic characteristics.