Plant growth regulators (PGRs), such as cytokinins (6-benzyladenine; BA) and gibberellins (GAs), are widely used in fruit production. This study focused on the plum cultivar “Čačanska rodna” (P. domestica L.) grafted on vegetative rootstock “WaVit” and generative rootstock Prunus cerasifera, with interstock Prunus spinosa. PGR treatments included 50 mg L⁻¹ and 100 mg L⁻¹ of BA and 200 mg L⁻¹ of gibberellin A3 (GA₃) and non-treated control. Pomological characteristics of plum fruits were examined at harvest, while physicochemical properties were analyzed at harvest and after 28 days of cold storage and 4 days of shelf life. GA₃ and BA application changed the fruit morphological traits, improved skin strength, and increased carotenoid, anthocyanin and sucrose content while decreasing the titratable acidity at harvest. The beneficial effects of higher sucrose, anthocyanin and carotenoid levels persisted in all PGR-treated fruits after cold storage and shelf life. GA₃-treated fruits had firmer flesh, stronger skin and higher total soluble solids (TSS) content, while in BA-treated plums, these effects were rootstock-dependent. The physical properties and chemical composition of plum fruit in the postharvest period suggest beneficial effects of the applied PGR treatments. Moreover, these chemical treatments might have prolonged the beneficial impact on fruit storability, nutritional profile and sensory properties. Based on our results, GA₃ preharvest treatment can be included in standard cultivation practices within contemporary production systems of European plums not only to improve fruit quality at harvest but also to improve the storage potential and nutritional value, regardless of the rootstock used.

Growing the sweet cherry on different vigor rootstocks, such as Colt and Gisela 5, in a high-density orchard, causes differences in growth and productivity and later imposes the need to change the growing system including pruning, flower and fruit thinning, irrigation and fertilization. In the present research, four sweet cherry cultivars (Summit, Kordia, Lapins and Regina) grafted on Colt and Gisela 5 rootstocks were assessed for morphological traits and productivity. The parameters investigated were: vegetative growth, bearing potential, fruit set, precocity, productivity, fruit growth habit and quality attributes. Compared to Colt, the trees on Gisela 5 had smaller TCSA and the length of two-year-old branches, in the fifth season after planting. Trees on Gisela 5 had a higher number of flower buds per may bouquet compared to Colt, which confirms that bearing potential is highly affected by the rootstock. Growing the sweet cherries on Gisela 5 induced a higher fruit setting in all cultivars except in Kordia. Fruit physical attributes were affected by the cultivar, growing system and experimental year. For all tested cultivars, the yield per tree was significantly lower on Colt compared to Gisela 5. Gisela 5 performed better than Colt, which suggests that Gisela 5 should be used as a rootstock in high density sweet cherry production systems.

DA‐meter enables quick and non‐invasive determination of fruit ripeness in different types of fruit, including apricots. In order to examine the postharvest physiology of apricots, fruits were divided into five I _AD categories (0.00; 0.01−0.40; 0.41−0.80; 0.81−1.20; and >1.20) and were analyzed in terms of the physicochemical and sensory properties at harvest, after 21 days of cold storage and after 3 days of shelf life. The specified I _AD categories differed in terms of ethylene production, flesh firmness, skin colour, composition and sensory properties at harvest. After cold storage and shelf life, ethylene production and respiration patterns, sensory properties, colour and fruit composition were affected by the I _AD value. Fruit assigned to the categories I _AD 0.81−1.20 and I _AD >1.20 categories maintained higher firmness compared with the remaining three groups. Carotenoid, phenol, fructose, sucrose, citric and succinic acid content were affected by the I _AD value during storage. Apricots attained optimal properties for consumption in different postharvest periods, depending on their maturity stage. These findings suggest that I _AD ‐based segregation can support apricot fruit management during storage and shelf life.

Sour cherry is one of the most important horticultural crops in the Hungarian market. Its flavour combination makes it ideal for fresh consumption as well as canned products. The Hungarian and European markets have requested for new varieties to be introduced, making the evaluation of breeding and prebreeding material a crucial point. A total of 30 sour cherry accessions from the genebank collection were investigated for their potential inclusion into the breeding program. The main aim of the study was to identify candidates for future breeding programs, selecting their colour profiling and total polyphenolic content (TPC). This study follows the antioxidant activity of cherry species by determining the total content in polyphenols. Polyphenols are found in higher concentration in cherries when compared to other plants and have been identified as free radical scavengers, which are useful to prevent the occurrence of several diseases. Furthermore, TPC has been observed as a contributor of bitterness, acidity, colour, flavour, odour, and oxidative stability. The accessions were evaluated for their colour, fruit weight, flavour profile, firmness, and TPC. Colorimetric data were compared among four methods to illustrate to the Hungarian breeders which of the available approaches is the most accurate for sour cherry breeding. Results suggested that several accessions appear relevant for the breeding program, such as ‘Pipacs 1′, ‘Bosnyák’, ‘Hortenzia Királynője’, and ‘Mogyoródi Kései’. The total polyphenolic content was highest in ‘Pipacs1′ and lowest in ‘Kántorjánosi 3′. ‘Pipacs 1′ and ‘Hortenzia Királynője’ had interestingly high acidity content and light to very light fruit colours. ‘Bosnyák’ had a deep and dark colour with high soluble sugar content. ‘Mogyoródi Kései’ appears to have the biggest fruit. All mentioned varieties will be included in future breeding programs.