Fruit growing
and viticulture of South Russia
The results of rooting the perspective clonal rootstocks for sweet cherry (P. avium) and sour cherry (P. cerasus) as well as was explored their compability with scion in the nursery are presented. The work was carried out at the base of the Krymsk EBS, VIR Branch in the rows, mist-forming systems for growing clonal rootstocks and nursery. The objects were clone forms that tested for rooting by lignified and green cuttings as well as their use as rootstocks of sweet cherries and sour cherries. The results of the research show that the tested forms have a high percentage of rooting the lignified and green cuttings. It was determined that the forms of C 56-12×VSL 2, C 39-4, A-9×VSL 2 (2341-1) and the LORY series have tolerance to cuttings which are infected by a ringspot virus. All tested forms in the nursery are well compatible with the varieties of sweet cherry and sour cherry, however, the Vstrecha cherry variety with rootstocks of VSL 2 and RVL 9 displays the mechanical incompatibility. Saplings that have been grafted on the exploratary forms begin to branch in the nursery, laying the first side-shoot at height of 50-70 cm. The tests with the sweet cherry variety of Lapins have shown that applying of RVL 8 rootstocks, which had been obtained by Krymsk EBS in 2000, contributes the better branching of saplings in the nursery and the increasing of inclination of the branch from stem over 75 . It is shown that the rootstocks that were studied have different growth vigor: the characteristics of C 56-12 ×VSL 2, A-9 ×VSL 2 2341-1, RVL 8 and Grizela 6 are the semi-vigorous and semi-dwarfs rootstocks. The series LORY and RVL 9 are the vigorous rootstocks.
To increase the productivity and stability of fruiting of plants, the horticulture industry needs the adaptive varieties and rootstocks in the specific growing zones. Based on global and local changes in weather and climate conditions, the selection of genotypes resistant to the most often occurring stresses of various types is a permanent process. The paper shows that in recent years, the directions in breeding to create the rootstocks forms that can reproduce under the conditions of elevated temperatures in the spring-summer period and a significant lack of moisture are especially relevant. The most of interest are rootstocks, which easily rooted by hardwood cuttings in the first field of the nursery, because this is the least costly method does not required large capital investments. Such rootstocks had already identified in the nursery as heat-resistant and drought-resistant, significantly increase in the adaptive potential of scion-rootstock combinations with their participation. An equally important characteristics in the South of Russia is the resistance of rootstocks to the bacterial cancer (Agrobacterium tumefaciens). The pathogen of root cancer is positively affected by a neutral or slightly alkaline soil environment, therefore this disease is often observed in the North Caucasus and its harmfulness is significant, the control disease measures are costly and difficult. As a result of research, we carried out the rootstocks of PK SK 1, PK SK 2 with high rooting of hardwood cuttings in the first field of the nursery and resistance to root cancer were selected. They were allocated to the elite and patented and introduced in the State Register of Selection Achievements. The use of these rootstocks in horticulture and nursery farming will allow us to use the resource-saving technologies and to obtain the high-quality planting material for stone fruit crops and to increase in the yield of fruit orchards.
The rootstocks that are highly productive and resistant to adverse environmental factors are one of the basic elements for constructing the modern intensive technologies for fruit crops cultivation. The rootstocks that are maximally adapted to climatic conditions are required, which can provide a high reliability and productivity of the garden. Of greatest interest are genotypes with a wide range of cultivation, this indicates a high biopotential of plants. The main goal of the work was to study the economically valuable traits of a number of clonal rootstocks for plum-tree, including the rootstocks of joint breeding of the North Caucasian Federal Scientific Center of Horticulture, Viticulture, Wine-making and the Stavropol Experimental Station of Horticulture during their cultivation under different ecological and geographical conditions in the Minsk Region (Belarus) and in the Prikuban gardening zone of the Krasnodar Territory (Russia). As a result of the studies, the influence of the soil-climatic conditions of the cultivation zones on the economically valuable indicators of rootstocks was revealed. The shoot formation ability of uterine bushes, the level of branching, and the clasterosporium affection o f annual shoots of VPK-1, BBA-1, Spring Flame, Speaker, PK SK 1 (PKG 25/1), PK SK 2 (PKG13 / 1) rootstocks were assessed. Their degree of rooting with green cuttings is estimated. The PK SK 1 and PK SK 2 rootstocks were identified according to the productivity of uterine-orchards in two studied zones. These rootstocks can be used in breeding as origin of drought resistance and heat resistance. They have a high percentage of rooting by green and lignified cuttings. According to the set of positive characteristics the rootstocks of SK 1 and SK 2 were allocated to the elite in 2018 and 2020, they were patented and were entered into the State Register of selection achievements of Russia.
The quality of the produced planting material of fruit crops has a direct impact on the longevity, the beginning of fruiting and productivity of orchards. For the planting material production of a high quality category, the various agricultural ways are used in the practice of world and domestic nursery farming. The global use of chemicals in the plant growing leads to aggravation of ecology, and the physical and biological components of the soil. All this extremely negatively affects the immunity and productivity of plants. In this regard, at present, the domestic gardening and nursery farming urgently needs the techniques and methods that would combine the efficiency and resource saving when growing the seedlings and explants in vitro. To solve this problem, the use of modern resource-saving technologies is necessary. Today, more and more attention is paid to methods of obtaining the high-quality planting material using the microbiological preparations and bioagents based on strains of bacteria and fungi. The microorganisms used synthesize a number of substances, including indolylbutyric acid, which stimulate the growth and development of plants, and significantly effect the rhizogenesis and inhibit the development of soil phytopathogens. The paper presents a literature review of domestic and foreign studies on the increased global use of microbiological preparations, their positive effect the various substances in the system plant-host - microbiological preparations - environmental conditions in various ecological and geographical areas. Based on the results of the presented review, a table has been compiled of the most effective interaction between various plants and biological preparation according to domestic and foreign studies. According to the analyzed data, the greatest influence the plant growth and development was exerted by bacteria and fungi of the genera: Bacillus subtilis, Pseudomonas aureofacience, Glomus spp., Pseudomonas fluorescens.
The biological potential of plum-tree allows to cultivate it according to innovative technologies involving the use of clone rootstocks and compacted planting schemes. The paper presents the results of observations of Eureka-99 and VVA-1 clonal rootstocks growing in the garden under the dry conditions of Astrakhan Region. The control was the trees grafted on apricot seedlings. The purpose of research is to assess the economic and biological indicators of Renclod Altana plum variety (peculiarities of tree`s growth and development, fast maturity, productivity, fruit weight) when growing on clone rootstocks and to base their use for laying the intensive plum plantations under the arid conditions of the Astrakhan Region. It was found that the clonal rootstock accelerate the beginning of the main development phenological phases of scion-rootstock combinations. Compared with the control, the winter dormancy period of plants studied ends 12 ... 14 days earlier, the beginning of vegetation and flowering are ahead of the control by 8...10 and 5...6 days, respectively. It is shown that the Renclod Altana variety on clonal rootstocks has more compact trees, their height at the age of six years is about 2.5...2.7 m, the crown volume is 2.1...2.4, m3, the cross-section area of the stem is 8.5...18.1 cm. In the first stage of research it is revealed the influence of weakly rootstocks tested the early fruiting of plum trees: flowering was observed in the second year, fruiting in the third year, on the seed rootstock in the fifth year. In the initial period of fruiting, the clonal rootstocks provided higher productivity of Renclod Altana plum trees which was 8.4 kg / tree on VVA-1 and 13.6 kg / tree on the Eureka-99. The largest plum fruits are formed on the semi-dwarf rootstock of Eureka-99 (30.4 g).