To accelerate the breeding process, studies were conducted to identify morphological, biochemical, and microbiological markers of raspberry resistance to Botrytis cinerea Pers. The research objects were leaves of cultivars and forms diff ering in their resistance to gray mold. Using optical microscopy, we found that the abaxial surface of resistant cultivar leaves had multiple trichomes (hairs) not only along the veins, but also in the interveinal spaces. Moreover, closely spaced yellow glandules were discovered there as well. On the abaxial leaf surface of susceptible cultivars, rare trichomes were located along the primary leaf vein (midrib). No glandules were observed. Electron microscopy convincingly demonstrated that the adaxial side of resistant cultivars was so densely covered with intertwined hairs of diff erent lengths that the plant cuticle was not visible. In susceptible cultivars, the hairs were sparse, and the cuticle could be seen. The correlation analysis between the mineral content in the leaves and the extent of damage to raspberry cultivars by Botrytis cinerea revealed a medium and weak dependence between these indicators. Thus, they cannot be used as reliable markers of resistance to gray mold of fruits. As a result of metabolomic profi le analysis, resistant cultivars were found to contain an increased amount (1.5-23.6 times) of compounds with antimicrobial (fungicidal) action in the composition of the epicuticular layer of leaves. They are as follows: lignoceric, decanoic (capric), pelargonic acids, as well as ethyl gallate, arabinofuranose, 1-butanamine. These compounds can be considered biochemical markers of resistance to B. cinerea and used for early seedling disease diagnosis. Strains of cultivated endophytic bacteria forms with established antifungal activity against Botrýtis cinérea were isolated from the leaves of the resistant cultivar Zhar-Ptica and selected form No. 11-165-10.

The article presents the results of phenological observation of flowering onset dates for male and female inflorescences. In addition, the study provides the data obtained through assessing a complex of fruit quality characteristics of 26 promising breeding forms. The forms were previously selected for the adaptability and productivity characteristics from the gene pool of hybrid forms at the North Caucasian Federal Scientific Center of Horticulture, Viticulture, Wine-making. Phenological observations showed that the flowering time of female and male inflorescences in 2022-2024 occurred on different dates. Moreover, its duration also varied. The beginning of female inflorescence flowering (the average for a three-year period) was dated April 18; the average flowering duration equaled 11 days. The beginning of male inflorescence flowering (the average for a three-year period) was dated April 11. The average flowering duration was 8 days. When evaluating the flowering type, we found that 12 samples were protandrous, 8 samples were protogynous. 6 samples were characterized as homogamous with protogyny observed in particular years. The identified time and type of flowering enabled us to select the most promising pollenizer samples, as well as to establish forms with a late flowering date in female inflorescences, which is a valuable trait for breeding. The undertaken assessment of the qualitative fruit characteristics showed that forms 17-2-14, 17-2-16, 17-2-20, 17-3-8 had a set of valuable traits such as a high percentage of kernel yield, kernel extraction from the shell whole or in halves, light-colored kernels. Moreover, they have thin/medium-thick shells. Form 17-3-8 has late flowering dates of female inflorescences along with a complex of economically valuable characteristics of fruits, which is of great interest for its further consideration as a cultivar. In addition, the following combinations of parental forms are recommended for use in breeding: samples with homogamous flowering (17-1-14, 17-18, 17-2-25, Vodnik, Timur) and with late flowering of female inflorescences (Novinka, Kazachiy, G-1-37). They produce a low yield or have dark-colored kernels and can be crossed with forms 17-2-16, 17-2-20, 17-3-8 characterized by a large percentage of kernel yield and its extractability, light-colored kernels. This will make it possible to obtain breeding material for selecting forms with the specified characteristics.

The paper presents data characterizing the biochemical and sensory properties of juice obtained from cherry varieties ‘Grechanka’, ‘Konfityur’, ‘Kupina’, ‘Shpanka Bryanskaya’, ‘Uifehertoi Furtosh’, and ‘Turgenevka’ (control), included in the bioresource collection of the Russian Research Institute of Fruit Crop Breeding, located in Oryol Oblast, Russia. The study proposes a sensory panel for organoleptic evaluation of cherry juice based on previously developed descriptor dictionaries and analyzes a number of biochemical parameters characterizing its flavor properties. In order to facilitate the rapid assessment of the organoleptic properties of cherry juice, a grading system for color, flavor, and aroma indicators was presented for each sensory level based on selected descriptors rated on a 5-point scale. Sensory analysis revealed that the juice from all studied varieties exhibited a typical rich ruby-red color for cherries, with the exception of the juice from the ‘Shpanka Bryanskaya’ variety, which was characterized by a light red color with brownish tones. The analysis showed significant differences in flavor and aroma compared to appearance. The ‘Konfityur’ and ‘Kupina’ varieties displayed the most harmonious flavor (sweeter, without sharp sourness). The juice from the ‘Uifehertoi Furtosh’ variety had the most astringent and sour flavor, while the juice from the ‘Grechanka’ variety was considered to have a flat flavor. The juices from ‘Turgenevka’ and ‘Uifehertoi Furtosh’ varieties were found to be the most aromatic. The physical and chemical characteristics of juices from all varieties met the requirements of Technical Regulations on Fruit and Vegetable Juice Products (TR CU 023/2011). The highest content of soluble solids was noted in the juices from the ‘Konfityur’ and ‘Grechanka’ varieties, while the highest content of phenolic compounds was found in the juice from the ‘Konfityur’ variety. The ‘Konfityur’ and ‘Kupina’ varieties exhibited lower levels of titratable acids. Moreover, the juice from ‘Konfityur’ demonstrated the highest value of sugar-acid index and anthocyanin content among the studied varieties. The study shows a correlation between the sensory and biochemical parameters of the juice. Thus, the content of soluble solids, titratable acids and anthocyanins has the greatest influence on the flavor. The obtained results are instrumental in developing products with specified parameters and predicting their quality.

Grapes can be classified as drought-resistant crops. However, water deficit, albeit required to produce a quality crop, negatively affects the growth, development, longevity, and resistance of grapes to diseases and low temperatures. High temperatures can also reduce crop quality. Therefore, the resistance of the particular grape variety determines the extent to which abiotic factors influence its productivity. In general, the plant responses to the effects of water deficit and temperature fluctuations are quite conservative; nevertheless, the genotype has a significant influence on the metabolic changes that ensure plant functioning under suboptimal conditions. A comprehensive understanding of the key factors that determine the response of grapes to external influences can identify an effective strategy for breeding, variety selection, or placement under suitable agroecological conditions. The paper aims to explore the leading factor in metabolic changes of grapes under the stress of drought and high temperature. The studies were carried out under controlled conditions. The influence of modeled drought, high temperature, as well as their combination on physiological reactions of the Cabernet-Sauvignon, Kutuzovsky, and Morozko varieties was analyzed. Variety and temperature effects were the leading factors of metabolic changes in grapes, while drought impacted the least number of physiological and biochemical parameters, probably due to a rather high drought resistance of grapes. The low level of cell damage (changes compared the control were about 5%), pigment apparatus (chlorophyll stability index more than 90 %), relatively low MDA content (31 and 33 μmol/g crude weight) can characterize the Kutuzovsky variety as more stable in comparison with Morozko and Cabernet-Sauvignon varieties. Adaptive processes were provided by adaptive degradation of starch, an increase in the content of soluble carbohydrates, high peroxidase activity, and an increase in the content of phenolic compounds. The combined effect of drought and high temperature caused inhibition of peroxidase activity, decrease in starch degradation, higher intensity of oxidative processes, and damage to grape tissues.

Highbush blueberry is one of the most common berry crops. The presence of polyphenolic compounds, especially anthocyanins and proanthocyanidins, determines the high nutritional value of blueberry fruits, as well as their potential health benefits for humans. A large number of studies have shown that regular highbush blueberry consumption can reduce the development and progression risk of several diseases caused by inflammation and oxidative stress. Moreover, it can positively affect the composition of the human intestinal microbiome. The work aims to study the content and composition of the main groups of polyphenolic compounds, organic acids, and sugars in fresh fruits of 7 blueberry cultivars (Coville, Elliott, Bluray, Bluegold, Goldtraube 71, Spartan, Rancocas). Fruits were collected from plants grown at the experimental cultivar testing site of the I.V. Michurin Federal Research Center. They were examined using modern analytical methods such as spectrophotometry, HPLC with photo-, refracto-, and mass-spectrometric detection. The content and profile of anthocyanins, proanthocyanidins, catechins, flavonols, hydroxycinnamic acids, organic acids, and sugars were examined in detail. In addition, the study determined the main specific chemotaxonomic features in the cultivar context. Drawing on the obtained results, cultivars with the highest anthocyanin and proanthocyanidin contents were identified. The article shows that the studied cultivars have potential for being used as raw materials to increase the nutritional value of human diets.

The paper presents the results of developing a convolutional neural network model for detecting and classifying diseases based on images of apple tree leaves and fruits. The study involves transfer learning for the YOLOv10-X model (You Only Look Once, version 10, Extra-large), pre-trained on the public COCO dataset (Common Objects in Context), which includes over 200,000 images and millions of annotated objects. The training dataset was compiled in the Research and Production Department of the Federal Horticultural Center for Breeding, Agrotechnology and Nursery (Russia). Artificial augmentation of the training dataset by rotating images, adding noise, and changing tints and shades increased the dataset to 2200 images. The Precision and Recall metrics, as well as the mean Average Precision (mAP) metric, were used to evaluate the performance of the model. The study demonstrated that the model effectively recognizes leaf lesions caused by scab, powdery mildew, rust, and various types of spots, achieving a mean Average Precision (mAP) of 0.6. The “spot” class appeared to be the most difficult to recognize (mAP50=0.411; Recall=0.324), while the “rust” class revealed the least difficulty (mAP=0.868; Recall=0.803). The study contributed to optimizing the model parameters, including the confidence threshold (0.48), the learning rate (0.01), the number of epochs (313) and the batchsize (8). Testing of a robotic platform equipped with RGB cameras indicated that automatic data collection at high frequency enables effective real-time monitoring of lesion dynamics.