AFLP Molecular Identification and Genetic Relationship of Chinese and Japanese Pear Cultivars Grown in Middle European Conditions

Abstract

In this study, 30 genotypes of genus Pyrus (five European cultivars, 16 Asian cultivars, three rootstocks, four interspecific hybrids, one landrace cultivar from Czech Republic (‘Krvavka’), Pyrus betulaefolia Bunge. and one intergeneric hybrid (Cydomalus)) were tested using AFLP markers. Twelve primer combinations generated a number of 1251 fragments of which 1064 were polymorphic with an average polymorphism of 85.3%. The dendrogram, created by using the UPGMA method, revealed a distinct genetic relationship between European and Asian pear groups. The intergeneric hybrid Cydomalus was separated in the cluster tree from both groups. The level of similarity coefficient between European and Asian pears was 0.75. Despite the fact that Pyrus betulaefolia Bunge was clustered in the European pear group, the average similarity coefficient between the European pear group and Pyrus betulaefolia Bunge (0.7704) was comparable to the similarity coefficient between the Asian pear group and Pyrus betulaefolia Bunge (0.768). Thus, the botanic species Pyrus betulaefolia Bunge can likely be considered as an intermediate genotype between European and Asian pears. The cultivar ‘Talgarskaja Krasavica’ (chance seedling of ‘Forest Beauty’), which pomologically belongs to the European pear group was clustered together with the interspecific hybrid ‘Wu Jiu Xinag’ (‘Ya Li’ × ‘Bartlett’) which on the other hand belongs to the Asian pear group. Thus, due to its position in the dendrogram the cultivar ‘Talgarskaja Krasavica’ could be considered as an interspecific hybrid.