Apples are among the most significant fruit crops in Russian horticulture. The wide variety, as well as the prominent economic potential of the crop, both enable its cultivation across many climate zones and bring orchard farming in general to the attention of investors in the agro-industrial sector. Breeders have met the rising challenges inherent in creating varieties that are superior in terms of productivity, abiotic- and biotic stress resistance, fruit quality and competitive fast-return capacity. In the present article, current research in apple breeding including methods for intensive selection is reviewed with a focus on breeding programmes for creating adaptive varieties having a high commercial and consumer value. Classical breeding can be complemented with modern techniques for an earlier selection of commercially valuable genotypes, identification of primary genotypes, as well as the creation of new donors and cultivars. The research achievements of leading national institutions in the development of apple varieties reflect additions to the Catalog of State-Permitted Cultivars of Agricultural Crops over the last decade. Most of the 422 permitted adapted apple cultivars are highly marketable due to having best-before-consumption dates in the winter. Despite current success in national orchard farming, further endeavours in crop breeding remain relevant today. Comprehensive research engaging genetics, physiology, phytopathology, virology, agrochemistry and nursery is essential for improving modern breeding programmes with the aim of supplying producers with high-quality planting material for a cost-effective, low pesticide, environmentallystable product.

Hydrangea macrophylla is a decorative blossoming shrub used in landscape gardening. Its mass regeneration is implemented through reproductive sterile in vitro culturing. The plant adaptation to ex vitro conditions is the most delicate final stage, when the shoots are frequently treated with biostimulators to improve growth, development and immunity. We aimed to study the adaptation of in vitro-cultivated Hydrangea macrophylla regenerants to non-sterile conditions. The following solutions were used in adaptation trials: 1) HB-101, containing silicon dioxide as the active component, extracted from pine wood and sap, plantain, cypress and cedar, that functions as a universal plant immunity and development vitaliser; 2) Zircon, containing a complex of hydroxycinnamic acids and their derivatives, stimulates rooting during adaptation and acts as a stress protector; 3) Epin, a natural brassinosteroid plant hormone, that displays anti-stress adaptogenic and strong growth-stimulating activity; 4) Plant, a natural organic fertiliser, which enhances plant nutrition and rooting. This article describes the in vitro — ex vitro adaptation in different Hydrangea macrophylla cultivars (Draps Wonder, Madame Hamard and Bichon) and the impact of different biopreparations (HB-101, 0.5 mL/L; zircon, 0.5 mL/L; epin, 1.0 mL/L; plant, 2.5 g/L) on the biometric indices (length and number of roots, number of leaves, height of shoots) and survival rate. With respect to the cultivar, the best adaptation rate attained 95.8-100 % in the substrate treatments that used zircon (0.5 mL/L) and epin (1.0 mL/L).

The impact of synthetic regulators on the growth and development of mandarin plants was investigated. It was shown that the exposure of plants to growth regulators had no effect on leaf chlorophyll content. Non-root application of nanoelicitor and siliplant synthetic regulators elevated the carotenoid content to 2.69-3.11 mg/g (control, water: 2.57 mg/g) and stimulated protective response. The total chlorophyll- carotenoid ratio in plants treated with nanoelicitor (4.29 mg/g) and siliplant (4.12 mg/g) was less than in the control, reflecting the degree of plant adaptation to adverse conditions in the growing season. Exposure to growth regulators improved photosynthetic activity and overall functionality. Chlorophyll fluorescence assays were used to evaluate photosynthetic activity coefficient as falling within a range of 0.54-0.57, which exceeded the control by 1.2-fold. Nanoelicitor was shown to induce active shooting and reduce fruit shedding. Compared to the control, growth regulators increased the retained fruit value by 1.5-1.9-fold and improved plantation productivity. Phytoregulators have shown promise in both improving the functional condition and reducing preharvest shedding in dwarf mandarin plants.

The article highlights current research that discusses the importance, role and application potential of endophytic bacteria in industrial horticulture. A review of national and foreign publications on the prevalence, taxonomic composition and function of endophytic bacteria in agricultural and horticultural plant objects is presented. Key endophytic bacterial phyla and genera associated with agricultural plants have been previously characterised. The authors consider the main plant organs and tissues that harbour endophytic bacteria, routes of bacterial colonisation and host-to-host transmission, endophyte relationships with the host species, as well as the genotype, seasonal period, environment, taxonomic and varietal composition of host plants. The host-microbiome relationship is intimate and mutually beneficial. Endophytic bacteria positively impact organogenesis and embryogenesis in agricultural plants, transforming phosphorus and atmospheric nitrogen into plant-absorbable forms and producing hormones that stimulate plant growth. Endophytic flora are able to produce vitamins, siderophores, phytohormones, antibiotic like-substances and phytopathogen-antagonistic exoenzymes, which play a role in enhancing a plant’s resistance to disease and stress, while simultaneously increasing its yield. Current evidence indicates the ability of endophytic bacteria isolated from garden crops to produce indolyl acetic acid, solubilise phosphates, potentially stimulate plant growth and suppress antagonistic phytopathogens. Endophytic bacteria are important regulators of growth, development and fruiting in garden crops, sustaining their reproduction and thus having a strong potential for use in biopreparations in industrial horticulture.

The study aimed to identify scion-stock combinations of early-maturing high-yield plum varieties and determine their cost-effectiveness. Long-term research was conducted at the Department of Fruit and Grape Genetic Resources and Breeding of the Crimean Experimental Breeding Station between 2008 and 2018. Continuous trials of scion-stock garden plum combinations during vegetation and fruiting produced optimal varieties for intensive cultivation with low- (VVA 1, Best) and mid-vigour (Kuban 86, Eureka 99, Druzhba) clone stocks. The Kubanskiy Karlik cultivar was the earliest maturing out of the VVA 1 stock cultivars, with an average yield of 7 kg/tree. Experimentally selected mid-vigour clone stocks that were found to be suitable and promising for intensive farming were Kuban 86, Eureka 99 and Druzhba. In terms of productivity and fruit size of the studied industrial varieties, the Best cultivar was selected from the low-growth clonal rootstocks using drip irrigation. The garden plum cultivars selected to be grafted on VVA 1 for intensive irrigation-based farming were: Kubanskaya Legenda, Golubaya Mechta, Sinyaya Ptitsa, Ballada, Naslednitsa, Debut, Stanley, Osenniy Suvenir. In non-irrigated areas, combinations that resulted in the highest yield (over 14 t/ha) were: Ballada/Eureka 99, Stanley/Druzhba, Sinyaya Ptitsa/Druzhba, Ballada/Druzhba, Ballada/Zarevo, Stanley/Eureka 99 and Sinyaya Ptitsa/ Eureka 99 for planting in 5×3 m plots; Kubanskaya Legenda/Best, Sinyaya Ptitsa/VSV 1 and Stanley/Best for planting in 5×1.5 m plots.

Economic losses incurred during raspberry storage are primarily a result of fungal spoilage. This study aimed to characterise the micromycete phytopathogenic complex in stored raspberries. The fungal microbiome was assessed in six Russian raspberry cultivars (Cleopatra, Novost’ Kuzmina, Sulamiph, Fregat, Shakhrazada, Yarkaya) as well as three foreign varieties (Glen Lyon, Cascade Delight, Limonnaya). The economic and biological traits of the cultivars were studied within the “Programme and Protocol for Fruit, Berry and Nut Crops Varietal Testing”. Internal and surfacelevel contamination in infected fruit tissues was detected via the stimulation of microbial growth in a wet chamber. The micromycete species composition was assessed via commonly used methods. The following raspberry spoilage organisms were identified as being predominant. Rots: black (Alternaria alternata (Fr) Keissler), dry (Fusarium Link.), leather (Phytophthora cactorum (Leb. et Cohn) Schroet), grey (Botrytis cinerea Pers.); moulds: black (Cladosporium Link.), green-blue (Penicillium Link.), green-yellow (Aspergillus P. Micheliex Haller), grey capitate (Rhizopus nigricans Ehrenb.), capitate (Mucor spp.); drupe rot (Phragmidium rubi Wint.); bacterioses. Microbiotic profiles varied between cultivars in storage. The fungal genera Fusarium and Alternaria prevailed, with the former dominating in almost all samples. The phytopathogenic complex primarily consisted of the fungal genera Fusarium, Alternaria and Penicillium. Raspberry cultivars which had a weak (Sulamiph, Shakhrazada, Novost’ Kuzmina) or strong (Cleopatra) resistance to micromycetes in storage were identified.

The jellification capacity of 16 cultivars and 79 selected nurselings of redcurrant from the All-Russian Research Institute of Fruit Crop Breeding collection was studied in order to identify the parental forms that can effectively produce well jellifying hybrids. Material processing and jellification assessment were carried out in compliance with the “Programme and Protocol for Fruit, Berry and Nut Crops Varietal Testing” (Orel, 1999) and GOST R 55462-2013. The assignment of cultivars into well-, medium- and poorly-jellifying categories revealed a declining average gustatory score from the well-jellifying towards the medium- and poorly-jellifying groups, (4.4, 4.3, 4.2 points, respectively), which indicates the significance of the jellification value in gustatory score. The well-jellifying cultivars were: Valentinovka, Podarok Leta and selected nurselings 78-2-100, 80-4-11, 164-22-88, 164-22-97 (4.6 points); Orlovskaya Zvezda, Dar Orla, Orlovchanka and nurselings 618-32-16, 79-1-89, 168-18-73, 84-1-105, 77-1-56, 164-22-41 (4.5 points). The jelly from the fruits of these varieties was characterized by a visually attractive dense jelly without separation (syneresis), as a result of which they can be recommended for obtaining natural pectin-containing products with or without the minimal use of additional gelling agents. Most of the trial cultivars were obtained by breeding of the Rote Shpetleze and Tchulkovskaya cultivars as paternal forms. Among the 46 siblings of the Rote Shpetleze cultivar, 28, 8, and 10 demonstrated good, medium and poor jellification capacities, respectively. Among the 25 siblings of the Tchulkovskaya cultivar, only three demonstrated good jellification, with three having medium jellification and the rest demonstrating poor jellifying capability. The majority of well-jellifying strains were obtained with Rote Shpetleze, which therefore can be recommended as parental material for creating varieties having a high fruit jellification capacity.