Branch union as the main indicator of the apple variety processability

Abstract. The article presents the results of study of apple varieties and hybrid progeny based on the branch union sign from the central conductor in order to identify genotypes for intensive gardening. The processability of the variety mainly depends on the genetically embedded structure of the crown of a particular genotype, which, among other things, is determined by the branch union. The study was conducted at the I.V. Michurin Federal Scientific Center, Central Black Earth Region (Tambov Region, Michurinsk). The objects of the study were Orlovim, Vympel, Rouville, Berkutovskoye, Fuji, Bylina, Honey crisp, Blagovest, Ligol, Academic Kazakov varieties. Ligol variety, widely used in intensive plantings, was selected as a control. Since the most important element of apple cultivation using intensive technologies is the formation of the crown of young trees, including pruning of fruit-bearing plants in the garden, these studies are relevant. The optimal branch union is considered to be an angle of 40-60°. It ensures reliable bonding of the central conductor and the outgoing branches. This breeding feature has been studied in the progeny of various combinations of crossing with the involvement of promising domestic and foreign varieties. As a result of the assessment of the hybrid progeny a wide range of variation of the branch union sign was revealed not only between different combinations of crossing, but also within a single family. The largest number of plants (more than 80 %) with an optimal branch union were observed in the following crossing combinations: Bylina x Honey crisp, Vympel x Academic Kazakov, Bylina x Vympel. In the future breeding for this trait, the most promising varieties are Akademic Kazakov, Honey crisp, Fuji, Vympel, Bylina. Keywords: apple tree, variety, breeding, hybrid offspring, branch union, intensive gardening, processability