Fruit growing
and viticulture of South Russia

Annotation

The paper presents an assessment of the effectiveness of clonal propagation of promising clonal rootstocks for cherry and sweet cherry. The demand in clonal rootstocks for small-stone crops is due to the intensification of their production. Clonal rootstocks of FSBSI NCFSCHVW breeding of the AI series meet the requirements for rootstocks: they provide restrained plant growth, a compact crown of trees, and are adapted to the edaphoclimatic conditions of the region. AI rootstock explants are best introduced during the period of active shoot growth from April 3rd to early June for propagation of rootstocks in in vitro culture. In this period, the regeneration of explants is the highest and, depending on the genotype, varies from 67.6 to 75.6 % in AI 1, from 7.2 to 83.4% in AI 11 and from 66.7 to 75, 85% in AI 70. At the stage of multiplication in the presence of 6-BAP at a concentration of 1 mg/l, all rootstocks develop well on Murashige-Skoog (MS) and DKW nutrient media. The largest number of shoots already after the first passage was noted on the DKW medium with the addition of Fe-EDDHA � 6.0-8.4 units/exp, with the addition of iron chelate Fe-EDTA, depending on the doubling, it is 4.6 up to 6.3 shoots per explant. In the control variant, 3.9 to 4.9 shoots are formed from one explant on MS medium with Fe-EDTA. In general, AI 11 and AI 70 rootstocks have a higher reproduction potential in all variants. Dispersion analysis showed a reliable influence of the factors �Nutrient medium� and �Form of iron chelate� on the reproduction coefficient for all studied rootstocks. The interaction both factors was observed only in AI 70 rootstocks. At the stage of micropropagation of AI series rootstocks, it is recommended to use DKW nutrient medium with iron chelate form Fe-EDDHA (100 mg/l) and 6-BAP 1.0 mg/l.

Annotation

The issue of obtaining planting material for fruit crops, free from pathogens, including viruses and phytoplasma, is of high relevance at the present time. The use of modern methods of biotechnology and molecular genetics is an important element in the production of improved planting material, since it allows not only to obtain plants in the culture of meristems in vitro and to produce their microclonal propagation, but also allows control the presence of viral and phytoplasmic pathogens, the identification of which by external symptoms can be difficult due to the presence of a latent form of disease. The article presents the results of the implementation of complex studies on microclonal reproduction of various crops of fruit crops, as well as an analysis of modern scientific literature on this topic. In addition, the results of molecular genetic studies in the part of the analysis of the genetic stability of plants obtained in vitro and the identification of viruses are presented. It was noted that at all stages of micropropagation, including the use of a culture of meristems, it is often necessary to develop variety-specific protocols. Optimal protocols for sterilization of explants of pome and stone fruit cultures using disinfecting tablets "OKA-TAB" and antimicrobial preparation �BIO-PAK� have been developed. The dependence of the intensity of the release of phenolic compounds by explants and their further necrotization upon introduction into culture in vitro on the phases of development and the age of donor plants was revealed. The optimal concentrations of nutrient media components, as well as phytohormones, have been established for a number of varieties and rootstocks of pome and stone fruit crops of domestic breeding. As part of the analysis of the genetic stability of plants obtained under in vitro conditions, ISSR and IRAP DNA markers have been identified that are promising for use for these purposes on apple stocks (ISSR: UBC 811, UBC 841 and UBC 843; IRAP: Cass 1 and �ass 2). When analyzing the genetic stability of the rootstocks of large-stone cultures using ISSR DNA markers, the identity of the DNA profiles was revealed, which testifies to the preservation of genetic stability for this rootstock using the developed micropropagation protocols. Based on the use of a complex of biotechnological and molecular genetic methods, genetically homogeneous rootstocks of stone fruit cultures, free from the virus pox disease of plum, were obtained. These plants, after testing for other viruses of stone crops and in the absence of such, will be transferred to the category of �candidates for initial� and, after retesting, can be transferred to the category of �initial plants� and serve as a basis for further mass production of virus-free rootstocks.

Annotation

Recently, the task of updating the walnut assortment with new adaptive and high-quality varieties of domestic breeding has been solved, since foreign varieties cannot fully realize their biological potential in the conditions of the North Caucasus. In order to solve the issue of import substitution, it is necessary to create competitive, highly productive varieties with lateral fruiting, adaptive to unfavorable factors. At the same time, an extremely important characteristic of the variety is the quality of the fruit. The article presents the results of research on the search for promising forms of walnut. During the route trips, a preliminary assessment of the studied samples was carried out for the presence of lateral fruiting and fruit load, as a result of which 11 promising forms were identified for assessing the morphometric characteristics and quality of the fruits. All 11 selected forms of walnut are valuable for breeding and can serve as sources of economically useful traits (lateral fruiting, large fruit, high percentage of kernel yield, light, well-filled kernel, thin shell). Forms � 1, � 3, � 4, � 5, � 6, � 7, �. 8, � 10 can be considered the most promising in terms of the complex of phenotypic characteristics of fruits. These samples have an average (� 1, � 5, � 7, � 8) and high (� 3, � 4, � 6, � 11) percentage of kernel yield, good kernel extractability, kernel completion and can be used in breeding work, such as sources of economically valuable traits.

Annotation

In connection with the intensification of horticulture, as well as the relevance of the issue of import substitution, the issue of creating potentially high-yielding varieties of walnuts that can realize their biological productivity potential in the conditions of the North Caucasus is becoming increasingly important, since not only high yield capacity and valuable characteristics of fruits, but also, the increased adaptability to the specific environmental conditions of the region. At the same time, the signs of fruit quality still have one of the key values for the competitiveness of the variety. The article presents the results of research on the search for promising forms of walnut. In the course of expedition trips in order to select promising forms of walnut, valuable samples were identified, in which the lateral type of fruiting and a complex of economically valuable characteristics of the fruit were noted. In general, all 16 selected walnut forms are valuable for breeding programs for various characteristics (type of fruiting, yield capacity, large-fruitedness, important economically valuable fruit traits). Sample Nj-4 has a level of fruit setting on lateral shoots up to 80 %, which suggests the prospect of its use for breeding purposes for this trait. Forms Krd-2, Krd-3, Ps-13, Din-5, Din-10 can be considered promising in terms of the complex of phenotypic characteristics of fruits. These sampleshave a percentage of kernel yield, with the exception of Krd-3 (43.0 %), more than 50 %, good kernel extraction, kernel completion and can be used in breeding work as sources of economically valuable traits.