Search

The I. V. Michurin Federal Scientific Center has concentrated a hazelnut genotypes collection of various ecological and geographical origin. Based on existing collection contemporary breeding work pointed at creating of new adapted to the soil and climate conditions of the Central Black Earth Region varieties of nuts. In this paper, we analyzed the indicators of frost resistance of hazelnut varieties of the species Corylus avellana L. and Corylus pontica C. (Koch.). Based on a comparative assessment valuable genotypes identification for producing and further breeding was the main purpose of the study. The paper shows the results of studying of 37 hazelnut varieties by the reaction to temperature decrease up to −40°C after standard quenching. We have identified the sources of high frost resistance, among which a special place is occupied by a new Schelkunchik variety. This genotype has no damage of the bark and cambium tissues, reversible damage of wood and vegetative buds, and a low level of male inflorescences lethality (2%). We have identified the frost resistance potential of the varieties Moskovskiy rubin, Ivanteevskiy krasniy, Pushkinskiy krasniy, Moscovskiy ranniy, Academik Yablokov. It is sufficient for cultivation of those varieties at the conditions of the Central Black Earth Region of Russia.

The gene pool of apple varieties of the Ural-Siberian and Far Eastern group has a valuable genetic potential especially in breeding for winter hardiness. Today, apple breeding research focused on winter hardiness using that varieties is limited. Using in hybridization gene pools created in harsh conditions of Siberia and the Far East will allow promoting the spread of apple culture to the north, which is mainly limited by frost resistance. Assessment of frost damage level of tissues and kidneys of apple shoots by -40°C temperature decrease was the principal goal of the work. According the national food and nutrition security policy, share of fruit production in the northern regions must be increased. In that case, ongoing scientific research has the defining value for these purposes. Different apple tree genotypes responses to low temperatures is highly individual and depends both of the degree or strength of frost and of the sensitivity of the plant itself. This complex interrelationship determinates the winter hardiness level under negative environmental conditions. 30 varieties of apple tree of the Ural-Siberian and Far Eastern groups were selected for study of frost resistance. Genotypes have a sufficient “margin of safety” for resistance to cause by frost damages.

The article presents an analysis of the biochemical composition of apple varieties (Malus domestica B.) with immunity to scab. Domestic and foreign apple varieties are used as research objects. Variability in fruits in the content of ascorbic acid (AA), soluble solids (SDS), P-active compounds, and titratable acids was noted. The high content of AA is noted in Uspenskoe, Skala, Bylina, Flagman, Yubilyar apple varieties. Long-term studies have revealed intervarietal differences in biochemical composition and variation of this trait over the years in apples. Varieties with valuable biochemical composition and immunity to scab can be used in organic food production, as well as in further breeding work to improve the quality of fruits.

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.