Fruit growing
and viticulture of South Russia

Annotation

Studying the rot of the seed chamber leads to the appearance of a micocomplex of 7 species fungi: 5 species of Fusarium Link and 2 species of Alternaria Nees. Presence of species on varieties in different gardens were heterogeneous. The set of plant species was unique for every variety and garden. The most number of species of pathogenic fungi was found on the Idared variety in the Timashevsky district. Two species of Fusarium was first discovered as rot causing agent of apple fruits in the Krasnodar Territory � F. solani (Mart.) Sacc and F. semitectum Berk. & Ravenel. Both species were found in the Dinsky district: one � at the Red Delicious variety, and the second � at the Starkrimson variety. Infection of flowers at the same time with two or three pathogens, which later co-developed in the seed chamber of the fruit, was established. The species of F. sporotrichiodes Sherb. was the most common in pathocomplexes. A study of the morphological and cultural characteristics of isolates of selected species in this study showed that cultural characteristics corresponded to those described earlier for these taxonomic units. For some species, the differences in growth rate, height, structure and color of aerial mycelium were noted. Most isolates of the species F. solani, F. semitectum, F. proliferatum (Matsushima), A. tenuissima ex Nees et T. Nees: Fries, and A. alternata (Fries: Fries) Keissler were characterized by rapid growth rates. According to the structure of the colonial aerial mycelium, homogeneous isolates � species F. solani, F. semitectum, F. avenaceum (Fr.) Sacc and heterogeneous isolates � species F. proliferatum, F. sporotrichiodes, were found. The color of aerial mycelium in most cases was homogeneous.

Annotation

Since 2013, in the Krasnodar Territory, fungi of the Fusarium Link genus have been the causative agents of rotting the apple fruits core, in 2019, 7 species of this genus have been identified as part of the pathocomplex. In order to effectively control the disease, in the pathogenesis of which a large number of species are involved, in vitro studies are required. It is necessary to achieve fast and guaranteed growth of each of the fungies. Significant variability of morphological and cultural characteristics of Fusaria is known during their cultivation under the influence of the composition of growing medium. In this regard, the selection for Fusarium fungi-pathogens of rot of the apple fruits core optimal for the cultivation of growing medium is actual. The studies were carried out by laboratorian and comparative analysis methods. We studied the growth of three pathogens of rotting the apple tree fruits core of the Fusarium Link genus in 10 growing medium. The radial colony growth rate and morphological and cultural characters were evaluated. As a result of studies in species F. semitectum (Mart.) Sacc., F. sporotrichioides Sherb. and F. solani (Mart.) Sacc. was found that not only the growth rate of the colonies was varied, but also their cultural characteristics depending on the growing medium. To cultivate the studied pathogenic fungi, carrot and tomato agar were isolated in the our experiments as universal medium on which the colony growth was most intense. Additionally, the growing medium were proposed for each species: for F. solani � Murashige and Skoog medium; for F. semitectum � medium Murashige and Skoog and wort agar; for F. sporotrichioides � Nirenberg medium, potatoes-glucosal agar and wort-agar.

Annotation

The production of Russian wine is based on the use of active dry yeast imported into the Russian Federation from European countries � France, Germany, Italy. Meanwhile, it is known that the high-quality wines of a geographical name must be produced using the local yeast races. The search for such races (strains) is an urgent task. Analysis of the genetic diversity of wild yeast populations and the creation of their collections is a necessary initial step in creating the new promising strains for industrial winemaking. Such studies are ongoing in Europe to create terroarspecific yeast strains. Grapes were sampled to isolate and study the new local strains of wine yeast in the vineyards of Temryuk and Anapa districts of the Krasnodar Territory. DNA isolation, conditions for PCR and fragment analysis were carried out according to current methods. To analyze the polymorphism length of amplified fragments during SSR genotyping, a fragment analysis was used on an ABIprism 3130 automated genetic analyzer. The data obtained were visualized in Gene Mapper v 4.1. A variety of species and genera of yeast on the surface of grape berries has been established. Moreover, the �yield� of saccharomycetes amounted to about 30 % of the total number of monospore cultures obtained for each of the selection points. The results of the analysis of genetic Relationships and a number of technological characteristics of strains of Saccharomyces sp. Isolated from natural population in ampelocenoses are presented. It was revealed that the geographical factor influenced the occurrence of genetic isolation. The genetically removed strains display the significant differences in a number of physiological and biochemical characteristics.

Annotation

To develop protective measures, it is necessary to identify the most dangerous and new harmful objects, as well as to select drugs with high efficiency. However, it is not always possible to assess the effectiveness of inhibition of a particular fungus species by chemical preparations; in addition, many phytopathogens can acquire a certain level of resistance to fungicides. For this reason, it becomes necessary to study the effectiveness of drugs against individual species using laboratory methods using pure cultures of fungi. The in vitro method makes it possible to evaluate the effectiveness of chemical preparations against pathogens in a fairly short time. However, there is the problem of the lack of a standardized method for assessing antifungal activity against economically important pathogens of agricultural crops. The studies were performed by two methods depending on the method of introducing the drug into the medium: by agar stab technique with a uniform introduction of the drug onto the surface of the nutrient medium and by inoculation the conidial suspension of the pathogen with a microbiological spatula when the drug is introduced on paper disks. The antifungal activity of chemicals against the fungus Alternaria alternata, the causative agent of apple fruit rot, varied in a wide range from no effect to strong, but in most variants of the experiment it was medium and the data obtained by the two methods of study were comparable. Comparison of these two methods showed a different degree of reproducibility of the results. So the most stable and repeatable results were given by the method with a uniform application of the working concentration of the drug to the surface of the nutrient medium and sowing by injection. In our study, the disk-diffusion method turned out to be more laborious, and the effects obtained by this method were not always characterized by an unambiguous interpretation and differed in repetitions, in comparison with the method in which the fungicide was applied directly to the agar plate, and the sowing was carried out by agar stab technique. Further optimization and standardization of this method is needed, including the amount of fungal inoculum applied and the thickness and evenness of the agar plate.

Annotation

The ability to effectively protect orchards against apple scab is threatened by Venturia inaequalis developing resistance to fungicides with a particular mode of action. Three pathogen populations from orchards in the Krasnodar region were used in dose-effect tests to examine the susceptibility of the apple scab pathogen population to cyprodinil. One of the populations was collected in an abandoned garden and was the baseline. The rest of the populations are collected in commercial gardens with the annual use of fungicides, including cyprodinil. The effect of 7 concentrations of cyprodinil was determined: 0.001, 0.01; 0.10; 0.50; 1.00; 10.00 and 50.00 mg/l for the growth of monospore pathogen isolates on Leroux synthetic medium. A total of 63 fungus isolates were analyzed. The growth of mycelium on the fungicide was expressed as a percentage relative to the control variant of the medium. The concentration of fungicide active ingredient that resulted in a two-fold inhibition of growth, called the effective 50 % concentration (EC50), was found using a probit regression transformation of the relative mycelial growth on the active ingredient. Analysis of dose-effect curves showed hormetic responses at low fungicide concentrations. The results of the study revealed that the sensitivity of the original population was significantly higher than that of the two fungicidal populations at a significance level of p