Fruit growing
and viticulture of South Russia

Annotation

Climate change on the planet is characterized by increased aridity in the regions where grapes are traditionally cultivated, the grapes is one of the most important crop in the world. Grapes vegetation takes a place at high temperatures, soil and atmospheric drought. Under such conditions, the plants are affected by a combination of abiotic and biotic stresses, causing the defensive reactions that are unique to each combination of stress factors. The aim of the research is to study the changes in the activity of antioxidant enzymes of various grape varieties under the influence of osmotic and high-temperature stresses. The objects of study were the leaves of different grape varieties, under the influence of simulated drought and high temperature. To simulate a drought, the leaves were dried for 2 hours at room temperature. To simulate the high-temperature stress, the grape leaves in the glasses with distilled water were kept n a thermostat for 2 hours at a temperature of +50 º�. Different enzyme isoforms have different activity when the environmental conditions change, so the formation of several isoenzymes with differtnt molecular weights may show the adaptive response of plants to stress. It is found that for the most of the studied grape varieties, short-term exposure to stress led to decrease in the number of peroxidase isoforms, and decrease in the activity of superoxide dismutase and a phenolic oxidizing peroxidase. The activity of ascorbate peroxidase changed less than the activity of the other two enzymes. The content of MDA, which indirectly characterizes the development of secondary oxidative stress, was markedly increased in all studied grape varieties. This reaction may be associated with the activation of signaling cascades in the grape plants, which requires an increase in the level of secondary oxidative stress, for the further formation of protective reaction. Our study have shown that different grape varieties are sensitive to different types of stress. These research will continue to study the reactions of grape plants at a longer exposure time of studied stress factors.

Annotation

The impact of cold stress is of great importance for scientific research in viticulture due to the relatively low cold resistance of grapes under the conditions of the viticulture zone of Russia, which leads to a significant decrease in yield. A better understanding of the physiological processes that influence the resistance of grapes to low temperatures is necessary for developing strategies to mitigate stress.The aim of this research was to study the changes in the antioxidant enzymes activity in grapes of different varietes with different cold- tolerance under the influence of the cold stress. Grape�s shoots and buds of resistant and non-resistant varieties were chosen as research material. As the result of this work the different reactions of grape buds and shoots tissues to the low temperature�s influence were observed. The resistant varieties were characterised by higher malonic dialdehyde content in vine tissues and buds than non-resistant varieties. For cold-resistant varieties the presence of high level oxidative processes are important for the activation of protective reactions. Influence of the cold stress resulted in elevation of antioxidant enzymes activity in the studied grape varieties. In the shoot`s tissues of resistant varieties the activity of these enzymes was higher than that of non-resistant varieties. Interestingly, that the relationships between cold-resistivity and antioxidant enzymes activity weren�t observed in studied buds, except for the peroxidase. n the studied varieties, there was no change in the number of peroxidase isoforms under conditions of low temperature stress, while its total activity significantly changed, which may be due to an increase in the expression of this enzyme. The activity of this enzyme changed drastically compared to the control. We suggest that the activity elevation of this enzyme is one of the defining protective reactions to the cold stress in grapes.

Annotation

Micropropagation is a promising direction for obtaining a healthy, genetically homogeneous grape planting material. The efficiency of reproduction is determined by many factors, including the acclimatization of plants to natural environmental conditions. The difficulty of transferring in vitro plants to non-sterile conditions is associated with a number of physiological and anatomical features of in vitro plants, among which the low level of photosynthetic processes is of particular importance. The influence of various concentrations of sucrose in the culture medium and additives, simulating environmental stresses on the rates of photosynthesis of grapes during acclimatization, was studied. The content of sucrose 10g/l in the culture medium was the most optimal for the formation of the photosynthetic apparatus. Both low and high sucrose content in the culture medium negatively affected the formation of pigments and the efficiency of photosynthetic processes. The introduction of PEG and NaCl into the nutrient medium led to a decrease in the total content of pigments, the quantum yield of photochemical reactions, but increased the expression of RUBISCO activase. The use of ABA as part of the culture medium had a positive effect on the formation of pigments in grape plants during acclimatization. The effects of weak stresses on the photosynthetic parameters of grapes in in vitro culture and during the acclimatization period are identical to the effects of drought and salinity under natural conditions. At the same time, these types of influence have a positive effect on adaptive �anti-stress� reactions that prevent plant damage under ex vitro conditions, which ultimately increases the level of growth processes and the yield of seedlings during micropropagation of grapes.

Annotation

The search for reliable methods for assessing the resistance of grape varieties to heat and drought is relevant in connection with the increasing climate instability in the Anapo-Taman viticulture zone. The purpose of the work is to conduct electrophoretic separation of peroxidases in polyacrylamide gel in the leaves of various grape varieties, to identify varieties with increased resistance to heat and drought. The objects of research are grape varieties of various ecological and geographical origin: Kristall (control) � Euro-Amur-American origin; Dostoynyi, Krasnostop AZOS � Euro-American origin; Vostorg � Amur-American origin; Zarif � Eastern origin; Aligote � Western European origin. It was established that the qualitative and quantitative composition of peroxidase isoforms changed during the summer and had a varietal feature. In June, 4-6 isoforms were isolated for each particular variety, in August � 2-4 isoforms. The Kristall variety stood out for its especially high resistance to heat and drought during the summer, both in the field and under the influence of artificial high-temperature and water stresses. This was achieved due to the multiple isoform composition of peroxidases and the constancy of their composition in response to stress. Varieties Dostoynyi, Vostorg, are highlighted as highly resistant to heat throughout the summer. The heat resistance of varieties Krasnostop, Aligote, Zarif changed during the summer period. In relation to drought, the varieties Kristall, Dostoynyi, Vostorg showed high resistance in early and mid-summer. According to the appearance and disappearance of peroxidase isoforms, the drought resistance of varieties Dostoynyi, Vostorg, Krasnostop AZOS changed during the summer. Aligote and Zarif varieties during the summer period stood out as not drought-resistant. The obtained data can be used as diagnostic criteria for assessing the degree of heat and drought resistance of grape varieties in different months of the summer period in the conditions of the Anapo-Taman zone of the Krasnodar region for breeding purposes.