Fruit growing
and viticulture of South Russia
Summarizing the results of research in the field of regulatory mechanisms of drought resistance in grapes for substantiate approaches to eliminating the impact of stress factors and minimizing their detrimental effects is the aim of this analytical review. There are considered the overall conceptions about the responses of grape plants against drought stress, as well as issues of genetic control, distribution of dry matter and secondary metabolism under water deficit conditions, influence of complex stresses on plants, genotypic determination of drought tolerance and significance of grape rootstocks in plant adaptation to drought. The adaptation system of grapes to water deficit is a complex set of specific genes that regulate various pathways associated with protection against stress. Understanding the differences in drought tolerance between existing genotypes creates the background for the development of new drought-resistant varieties. A comprehensive characterization of a number of physiological and biochemical properties makes it possible to evaluate grape genotypes for drought resistance. The study of the principles of coordination between biotic and abiotic responses against stress is becoming increasingly important. The use of drought-resistant rootstocks is an important strategy for adapting to water deficit conditions. Coordination between scion and rootstock is carried out to regulate water use by plants. The application of biotechnological approaches is recommended in order to eliminate the main biotic and abiotic stress factors for grapes. In vitro experiments using polyethylene glycol to simulate drought appear promising. The conducted investigations of grapes in water deficit conditions provided valuable information for further scientific research. The identified regulation mechanisms of plant homeostasis are to be used in the development of modern breeding strategies to increase the resistance of grapes against drought.
Rationing the bush load with shoots and bunches allows to effectively manage the productivity of grapes. The research is to study the productive variability of grapes under the influence of differentiation of bush load with shoots and bunches, to optimize the regulations of agrotechnology of the table variety Livia (Flamingo × Arcadia) on the Oppenheim SO4 rootstock. The research was carried out in the Central Agroecological viticulture zone of the Krasnodar region, in vineyards with drip irrigation. Planting scheme is 3.8×2.0 m. The variety has a high responsiveness to the optimization of the structural elements of the bush. There is a change in the bunch size and the yield capacity of grapes when varying the number of vegetative and generative organs in plants. This makes it possible to optimize the regulations of bush management for obtaining high yields and large bunches of grapes. The largest bunch size, 567 g, is formed in the presence of 25 shoots and 28 bunches per bush; the highest yield capacity, 23.34 t/ha, including commodity yield capacity 20.59 t/ha, is formed with 25 shoots and 33-35 bunches per bush. Grape yield capacity against the background of increased and reduced bush load with bunches are in a strong and direct correlation with the shoot load. Against the background of an increased load of bushes with bunches, the correlation coefficient is r = 0.71; with a reduced load, r = 0.99. Against the background f a moderate load of bushes with bunches, the correlation dependence of grape yield capacity on the number of shoots is moderate and direct (r = 0.49). The bunch weight of grapes is in close and medium direct dependence on the load of bushes with shoots, close and average inverse dependence on their number.
The article presents the results of studying the effect of gibberellin on the formation of grape berries of seedless varieties of AZESV&W breeding in order to develop technological parameters of its application. The research was carried out on kishmish grape varieties Lotos, Zhemchug Anapa, Kishmish Rozovyi AZOS in agroecological conditions of the Black Sea zone of Southern Russia. The scheme of the experiment included options for using gibberellin twice and three times in the phases of grape vegetation: budding (5-7 days before flowering), pollination and fertilization (mass flowering), post-fertilization (10 days after flowering). The treatment was carried out manually with full immersion of inflorescences in a container with a solution of gibberellin 0.5-1 liter per bush, depending on the strength of the bush and the growth phase, dosages: 0.25 ml., 0.5 ml., 0.75 ml., 1 ml per liter of water. It was found that the double use of gibberellin leads to the desired quality of grapes, both according to consumer preferences an increase in the size of berries, a decrease in the average weight of rudiments of seeds in the berry, and according to technological requirements an increase in the average weight of the pulp and skin. The repeated use of GA, starting from the budding phase, increases the likelihood of undesirable effects, leads to shedding and different quality of the ovaries, pea berries up to 37 % in the Lotos variety, up to 25 % in the Kishmish Rozovyi AZOS variety, Zhemchug Anapa variety up to 12 %. It has been established that the optimal use of gibberellin on seedless grape varieties of the AZES breeding is a double treatment with a GA solution with a concentration of 0.75 ml per liter of water during the mass flowering phase with an interval of 10 days.
In 2016-2021, in the Krasnodar region, in the conditions of the Taman soil district (central region of the steppe zone, southern chernozems (chestnut), Temryuk district), the influence of biomineral fertilizers of special compositions on the main productivity indicators of table grape varieties Augustine and Moldova was studied. Fertilizers were applied by the nonroot method in the form of aqueous solutions, in accordance with the developed regulations. The research methodology was developed in accordance with the regulation on the relationship of abiotic factors and the effectiveness of fertilizers. In this regard, the research program assumed the analysis of edaphic factors, accounting and registration of the dynamics of temperature extremes, which revealed the uniformity of soil conditions of experimental sites and significant fluctuations of hydrothermal factors. The solution of research tasks was carried out with the help of one-factor field trial. As a result of the experiment, it was found that, depending on the amount of precipitation and fertilizers used, the number of fruiting shoots and inflorescences was formed, significantly exceeding the indicators in the control version (without fertilizers). Higher productivity of shoots per unit area of planting was revealed. Top dressing contributed to a significant increase in the bunch weight of grapes, mainly due to an increase in its density. The sugar content in grape juice increased by 7.3-17.3 %, depending on the variety. In 2016-2018, when using special complexes of nutrient salts of various brands with preparations containing Ascophyllum nodosum algae extract and amino acids, the economic yield capacity of grapes was higher in comparison with the control variant. In 2019-2021, against the background of the use of the adaptogen Normat L, the yield capacity of grapes exceeded the value of the indicator in the control variant by 38.4-38.6 % (Augustine variety) and 24.0-40.9 % (Moldova variety). The experimental data obtained characterize the application of biomineral fertilizers by the nonroot method as a sufficiently justified way to control the production process and the quality of the grape yield.
The materials of the study of agrochemical and microbiological indicators of leached chernozem in the orchard agrocenosis and field crop rotation are presented. The peculiarities of the distribution of the main elements of plant nutrition and organic matter by layers in the upper part of the soil profile, depending on the type of cultivated crop, are revealed. As a result of the evaluation of the main groups of microorganisms of leached chernozems, 830 strains of pathogenic and conditionally pathogenic micromycetes were identified, among which Aspergillus spp. and Penicilium spp. predominate. The number of micromycetes in the studied areas differs slightly, however, in the upper layer (0-10 cm) of soils under the garden cenosis there is a sharp increase in them. It has been established that in the soils of the orchard cenosis there is a fivefold decrease in the number of bacteria in comparison with soils in the conditions of field crop rotation. The number of bacteria gradually decreases with depth. Correlations of the total number of fungi strains and colony-forming units of bacteria on the content of organic matter, nutrition elements, the total amount of salts and the reaction of the soil environment have been established. A close correlation between micromycetes and bacteria (r = 0.99), humus (r = 0.95), mobile potassium (r = 0.93) and pH (r = 0.89) was revealed in the soils of orchard cenosis. There are no close correlations in the field crop rotation. Data on the ratio of bacteria and micromycetes indicate a higher suppressiveness of soils in the conditions of field crop rotation and the depletion of the microbial pool of soils of orchard cenoses. This indicates the development of the process of soil fatigue and a decrease in the resistance of leached chernozems to phytopathogens during prolonged cultivation of an apple orchard in a monoculture.