Porfiry Afanasyevich Dibrova was one of the first scientists and breeders standing at the origins of scientific pomiculture in the Urals. He was the author of 23 cultivars of apple, six of pear, one of sour cherry, and one of black currant. In the 1940s, he was the leader of collecting missions exploring the local assortment of fruit and berry crops in 50 districts of Sverdlovsk and Molotov (Perm) Provinces, and the Udmurt Republic. P.A. Dibrova was one of the authors of the first standard set of fruit and berry cultivars for the abovementioned areas. He studied regularities in the inheritance of valuable agronomic and biological traits of fruit crops and identified promising sources for apple and pear breeding. He launched the main plant breeding trends in the Middle Urals, now followed by contemporary breeders: the development of highly winter-hardy cultivars of apple and pear with fruiting precocity, stable yields, excellent fruit quality, and improved biochemical composition in fruits.

One of the directions of apple breeding in the Middle Urals is the development of varieties with a long-term storability. The ability of apples to maintain their consumer qualities for a long period is one of the most important indicators of the variety. A significant role in the storage of apples is played by the amount of ethylene produced in them. The paper presents the results of identification of genes involved in the control of ethylene biosynthesis in apple varieties selected by the Sverdlovsk horticultural breeding station. A total of 21 apple varieties were analyzed. The main objective of the study was to detect Md-ACO1-1 and Md-ACS1-2 alleles in the homozygous state. The combination of these alleles in one genotype reduces the production of ethylene in fruits, which contributes to their long-term storability. The analysis showed the availability of polymorphism in the two studied genes. The Md-ACO1 gene is characterized by the availability of two alleles in most varieties. The homozygous Md-ACO1-1 allele was identified in the Isetskoe pozdnee variety. Analysis of the Md-ACS1 gene revealed the predominance of the Md-ACS1-1 allele form. The Md-ACS1-2 allelic form was observed only in heterozygous samples. No combination of Md-ACO1-1 and Md-ACS1-2 alleles was found in the homozygous state. However, heterozygous forms are also of interest for breeding. They can serve as a source of a character of reduced ethylene biosynthesis when creating varieties with a long-term storability. Such varieties are Sokol yasnyy, Aksena, Rozovatoe zimnee, Sverdlovchanin, Isetskoe pozdnee, Blagaya vest'. The comparison of fruit storage periods and the genotype of the variety has been made. Allelesassociated with a reduced level of ethylene biosynthesis are typical both for the varieties with low and high storability.

No abstract

No abstract

Background. Microsatellite (SSR) markers are now widely used both for studying genetic diversity in fruit crop collections, including apple (Malus × domestica Borkh.), and for genotyping individual accessions. The apple collection held by VIR, being the largest in Russia, contains cultivars bred at five experiment stations of VIR. These cultivars not only meet the requirements of horticulture in the region of their origin, but also are interesting as sources of valuable traits for breeding programs. However, these cultivars have not previously been studied using microsatellite markers. Materials and methods. A set of 10 SSR markers (CH02c02b, CH03d01, CH01f03b, CH02d08, CH02c02a, CH05e03, CH02c09, CHVf1, CH01h01, COL) was used for genotyping 35 apple cultivars developed at VIR and four parental forms. Fluorescently labeled PCR products were separated by capillary electrophoresis on ABI Prism 3130xl.Results. In 35 apple cultivars from VIR, 97 alleles were identified at ten studied loci. The number of alleles per locus varied from 5 (CH02c02b) to 17 (CH02c02a). The frequency of unique alleles was 26,8%, with 12,4% for rare alleles. Polymorphism information content (PIC) values varied from 0,49 (CH02c02b) to 0,91 (CH02c02a) and averaged 0,76. Expected and observed heterozygosity levels averaged 0,79 and 0,56, respectively. Cluster analysis did not reveal a clear division of cultivars according to the place of origin (experiment stations of VIR), but revealed clustering according to pedigrees.Conclusion. A high level of polymorphism was observed in 35 apple cultivars from VIR using ten SSR markers. The obtained data on the allelic composition of the studied cultivars can be used for their identification and contribute to more efficient collection  management. Further studying and SSR genotyping of VIR’s apple collection and comparison with the data obtained in the presented work can help to identify the origin of cultivars with unknown pedigrees.