Biological potential of the Carmen apple variety in the South of Dagestan

Abstract

The article provides a pomological estimation of the Carmen apple variety cultivated in the southeastern foothill sub-province of Dagestan. The purpose of the research is to study the biological potential of the variety and to reveal the best in productivity apple scion/stock combinations that combine high adaptive capabilities for constructing intensive-type orchards in the commercial horticultural zone. The establishment of such orchards is associated with high material costs; therefore, improving the technology plays a crucial role. Especially important is the selection of scion/stock combinations in the production of apple planting material, which in the intensive horticulture should be characterized by precocity, stable productivity, high fruit quality and environmental sustainability. In Dagestan, fruit zones are sharply heterogeneous in terms of soil and climate conditions, which prevents the unification of the technology of intensive apple plantations. The most promising for the development of commercial horticulture is the South-Eastern foothill sub-province. Among the unfavorable environmental factors that negatively affect the vital activity of fruit crops in Dagestan, the first place is occupied by recurrent cold in spring and early frosts in autumn. In accordance with the Program of scientific research of the Federal Agrarian Scientific Center of the Republic of Dagestan, it is planned to study the influence of different stocks – dwarf M9, SK7 and medium-tall SK2, MM106 on the productivity of the Carmen variety. Based on the research results, biometric parameters of tree growth in a young orchard were studied depending on the design of the plantings. It is noted that at the three-year-old, the condition of the trees estimated on a 5-point scale is good. The height of the trees, depending on the stock, reached an average of 1.9 to 2.6 m. On dwarf rootstocks M9 and SK7, the diameter of the tree stem in the Carmen variety was 3.0-3.3 cm; on stocks SK2 and MM106, respectively 3.6-4.0 cm. The most prominent growth activity of trees of various scion/stock combinations reflects the total length of shoots. The smallest shoot length was observed in stands with dwarf rootstocks M-9 and SK-7, the largest – on medium-sized rootstocks MM-106. The largest number of fruit formations was on the dwarf rootstock SK7 (24.7 PCs.), with a planting scheme of 3.0×1.5 m; per square meter of food area, the number of fruit formations was 4.3-5.4 PCs./m2, and on stocks SK-2 and MM-106 with a planting scheme of 5.0×2.0 m their number was 2.1-2.2 PCs./m2.