One of the approaches to intensify horticulture is to introduce cultivars with an unusual canopy into commercial production. Such plants can be columnar Apple trees. In modern breeding, there is a trend to create cultivars with a compact canopy. In such orchards, it is reduced to a minimum the cost for pruning, harvesting, and protection against pest and disease, which are the main expenses in apple orchards with a traditional canopy. The use of molecular markers linked to columnar growth habit allows us to identify a physiological sign at an early stage of growth: in the juvenile period. The assessment of apple cultivars and hybrids was carried out at the I. V. Michurin Federal Scientific Centre in 2015-2018. Four markers were used in the research: Mdo. chr 10.12, C18470-25831, 29f1, and jwlr to identify plants with the columnar growth habit gene (Co). The use of various DNA markers made it possible to establish that not all of them are well linked to the Co gene. In the research process, primers were identified for markers 29f1 and jwlr, which reliably allowed us to identify plants with columnar growth habit at the juvenile stage, which will significantly reduce the breeding process.
Fine genetic mapping of the Co locus controlling columnar growth habit in apple
