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Precipitation in the plum rain period accounts for 40%-50% of annual precipitation in the monsoon region. To clarify the temporal variability of the isotopic composition of precipitation during the plum rain period from event to interannual time scale and identify the influencing factors, we analyzed the isotopic composition of precipitation and its influencing factors in Nanjing from 2015 to 2022. By using the Hybrid Single-particle Lagran-gian Integrated Trajectory (HYSPLIT) model with specific humidity analysis, we investigated the water vapor source and influencing factors. The results showed that 1) the isotopic abundance of atmospheric precipitation was depleted in the summer and enriched in winter. dx was lower in summer and higher in winter. The isotopic abundance of precipitation from the plum rain was depleted compared to mean value of the whole-year. 2) There was no significant correlation between δ2H and δ18O of the plum rain (precipitation) with local meteorological factors. However, dx was lower in light rain, reflecting the effect of sub-cloud evaporation. The average dx was higher during plum rain period in years with more total plum rain precipitation. 3) The low-latitude South China Sea and the western Pacific Ocean source area provided water vapor for the plum rain. The shift of moisture source region led to abrupt changes in precipitation isotopes. Our results could provide data support for studies on precipitation isotopes in the monsoon region, as well as a reference point for further understanding the precipitation mechanism of the plum rain and stu-dying the seasonal variability of atmospheric circulation in the East Asian monsoon region.

Developmental stages of peach, plum, and apple fruit influence development and fecundity of Grapholita molesta (Lepidoptera: Tortricidae).

Host plant attributes are essential factors determining the population dynamics of herbivorous insects. The developmental stage of host plants, in particular, may affect the biology of Grapholita molesta (Busck), a possibility that has rarely been examined. Here we assessed the effect of developmental stage of plum, peach, and apple fruits on the development and fecundity performance of G. molesta, along with an examination of the firmness and sugar content of the fruits. Among the fruits collected earliest (May 31), plum and apple were better food sources for G. molesta compared to peach in terms of development, reproduction, and life table parameters. However, despite the higher sugar content in peach, G. molesta larvae showed a lower rate of fruit penetration in peach, probably due to fruit firmness. In the later-collected fruit (June 25), both peach and apple were better than plum, as peach and apple were softer and had higher sugar content. Nevertheless, the penetration rate of larva was still low in peach probably due to pubescence on the fruit surface. Although the plum fruits in the later collection date were softer with higher sugar content, there was a negative impact on the development and reproduction because fruits started to liquefy earlier. In conclusion, the developmental stage of fruits with changes in fruit firmness or sugar content affected the development and reproduction of G. molesta, and apple would be the best food source.

Dynamic changes impact the plum pox virus population structure during leaf and bud development.

Plum pox virus (PPV) is a worldwide threat to stone fruit production. Its woody perennial hosts provide a dynamic environment for virus evolution over multiple growing seasons. To investigate the impact seasonal host development plays in PPV population structure, next generation sequencing of ribosome associated viral genomes, termed translatome, was used to assess PPV variants derived from phloem or whole leaf tissues over a range of plum leaf and bud developmental stages. Results show that translatome PPV variants occur at proportionately higher levels in bud and newly developing leaf tissues that have low infection levels while more mature tissues with high infection levels display proportionately lower numbers of viral variants. Additional variant analysis identified distinct groups based on population frequency as well as sets of phloem and whole tissue specific variants. Combined, these results indicate PPV population dynamics are impacted by the tissue type and developmental stage of their host.

Identification of early fruit development reference genes in plum.

An RNAseq study of early fruit development and stone development in plum, Prunus domestica, was mined to identify sets of genes that could be used to normalize expression studies in early fruit development. The expression values of genes previously identified from Prunus as reference genes were first extracted and found to vary considerably in endocarp tissue relative to whole fruit tissue. Nine other genes were chosen that varied less than 2-fold amongst the 20 RNAseq libraries of early fruit development and endocarp tissues. These gene were tested on a series of developmental plum fruit samples to determine if any could be used as a reference gene in the analyses of fruit-based tissues in plum. The three most stable genes as determined using RefFinder were IPGD (imidazole glycerol-phosphate dehydratase), HAM1 (histone acetyltransferase) and SNX1 (sorting nexin 1). These were further tested to analyze genes expressed differentially in endocarp tissue between normal and minimal endocarp cultivars. To determine the universality of those nine genes as fruit development reference genes, three other data sets of RNAseq from peach and apple were analyzed to determine the reference gene expression. Multiple genes exhibited tissue specific patterns of expression while one gene, the SNX1, emerged as possessing a universal pattern between the Rosaceae species, at all developmental stages, and tissue types tested. The results suggest that the use of existing RNAseq data to identify standard genes can provide stable reference genes for a specific tissues or experimental conditions under exploration.

Histochemical Analysis of Anthocyanins, Carotenoids, and Flavan-3-ols/Proanthocyanidins in Prunus domestica L. Fruits during Ripening.

As a result of the high variability of fruit properties in the European plum Prunus domestica, a histochemical analysis of fruits at different stages of development was performed to understand the ripening process in cv. 'Colora' (yellow-red skinned) and cv. 'Topfive' (purple skinned). Histological analysis showed that carotenoids in the fruit had two different origins. In the fruit flesh, they derived from chloroplasts that turned into chromoplasts, whereas carotenoids in the fruit skin derived probably from proplastids. Flavan-3-ols and proanthocyanidins showed differential localization during ripening. They were visible in the vacuole in different fruit tissues or organized in tannosomes in the fruit flesh. Tanninoplasts were observed only in hypodermal cells of 'Colora'. Toward maturity, anthocyanins were detected in the epidermis and later in the hypodermis of both cultivars. The study forms a basis for the analysis of the biosynthesis of secondary metabolites in European plums and their biological effects.

Impact of year of harvest, genotype and cultivation method on bioactives and Pru d 1 allergen content in plums.

The present work studied the effect of the year of harvest, the genotype and the cultivation method on the nutritional quality and the allergen content of three plum cultivars. The common quality parameters and the phytochemical content strongly varied with the year and the cultivar, while the system of cultivation had a minor influence. In particular, ascorbic acid greatly decreased in 2016 compared to 2015, while polyphenols were higher in 2016. The health-promoting compounds, and particularly phenolics, were significantly correlated with the antioxidant capacity. Finally, the allergen content was strongly dependent on the content of flavan-3-ols, suggesting that this class of phenolics is determinant in influencing the allergen content in plums. Results showed that the major factor affecting the quality and the concentration of natural metabolites of plum, in addition to the diversity among genotypes, is the year-to-year variation, whereas the system of cultivation plays a marginal role.

Oxalic acid preharvest treatment increases antioxidant systems and improves plum quality at harvest and during postharvest storage.

BACKGROUND: Plums are much appreciated by consumers as fresh fruit but have a limited storage life. Since reactive oxygen species (ROS) are associated with fruit ripening, an increase in ROS scavenging antioxidant systems could lead to a delay in postharvest plum ripening and in maintaining fruit quality after long cold storage. RESULTS: Results showed that crop yield (kg per tree) and fruit weight were enhanced by preharvest oxalic acid (OA) treatment of plum cultivars ('Black Splendor' and 'Royal Rosa'), although the on-tree ripening process was delayed. In addition, the ripening process during cold storage was delayed in plums from OA-treated tress, manifested by lower firmness and acidity losses and reduced ethylene production, as compared with fruits from control trees. Antioxidant compounds (phenolics, anthocyanins and carotenoids) and the activity of antioxidant enzymes were higher in plums from OA-treated trees than in controls, at harvest and during 50 days of cold storage. CONCLUSION: OA preharvest treatment could be a useful tool to maintain plum quality properties during long-term storage, by delaying the postharvest ripening process through a delay in ethylene production, with an additional effect on increasing bioactive compounds with health beneficial effects. © 2018 Society of Chemical Industry.

Changes in secondary metabolites, organic acids and soluble sugars during the development of plum fruit cv. 'Furongli' (Prunus salicina Lindl).

BACKGROUND: Organic acids, sugars and pigments are key components that determine the taste and flavor of plum fruit. However, metabolism of organic acid and sugar is not fully understood during the development of plum fruit cv. 'Furongli'. RESULTS: Mature fruit of 'Furongli' has the highest content of anthocyanins and the lowest content of total phenol compounds and flavonoids. Malate is the predominant organic acid anion in 'Furongli' fruit, followed by citrate and isocitrate. Glucose was the predominant sugar form, followed by fructose and sucrose. Correlation analysis indicated that malate content increased with increasing phosphoenolpyruvate carboxylase (PEPC) activity and decreasing nicotinamide adenine dinucleotide-malate dehydrogenase (NAD-MDH) activity. Citrate and isocitrate content increased with increasing PEPC and aconitase (ACO) activities, respectively. Both acid invertase and neutral invertase had higher activities at the early stage than later stage of fruit development. Fructose content decreased with increasing phosphoglucoisomerase (PGI) activity, whereas glucose content increased with decreasing hexokinase (HK) activity. CONCLUSION: Dynamics in organic acid anions were not solely controlled by a single enzyme but regulated by the integrated activity of enzymes such as nicotinamide adenine dinucleotide phosphate-malic enzyme (NADP-ME), NAD-ME, PEPC, ACO and NADP-isocitrate dehydrogenase. Sugar metabolism enzymes such as PGI, invertase and HK may play vital roles in the regulation of individual sugar metabolic processes. © 2018 Society of Chemical Industry.

Current achievements and future directions in genetic engineering of European plum (Prunus domestica L.).

In most woody fruit species, transformation and regeneration are difficult. However, European plum (Prunus domestica) has been shown to be amenable to genetic improvement technologies from classical hybridization, to genetic engineering, to rapid cycle crop breeding ('FasTrack' breeding). Since the first report on European plum transformation with marker genes in the early 90 s, numerous manuscripts have been published reporting the generation of new clones with agronomically interesting traits, such as pests, diseases and/or abiotic stress resistance, shorter juvenile period, dwarfing, continuous flowering, etc. This review focuses on the main advances in genetic transformation of European plum achieved to date, and the lines of work that are converting genetic engineering into a contemporary breeding tool for this species.

Compositional modifications of bioactive compounds and changes in the edible quality and antioxidant activity of 'Friar' plum fruit during flesh reddening at intermediate temperatures.

Flesh reddening of 'Friar' plum (Prunus salicina Lindl.) fruit developed rapidly during storage at intermediate temperatures of 5 and 15 °C in comparison to flesh turning yellow at 25 °C and almost no colour change at 0 °C. Thus, modifications of phytochemicals and antioxidant activity during flesh reddening were investigated. Anthocyanins accumulated rapidly in reddening flesh tissue and cyanidin-3-O-glucoside was identified as the absolutely predominant individual anthocyanin. Anthocyanins contributed greatly to the antioxidant activity at 5 °C, and especially at 15 °C by combining with non-anthocyanin phenolics, including protocatechuic, syringic, trans-p-coumaric and caffeic acids. Storage at 15 °C impeded the hydrolysis of sucrose to glucose and fructose, while storage at 5 °C maintained sucrose and accumulated fructose. Intermediate temperatures altered organic acid compositions helping to produce reasonable SSC/TA ratios. These results would provide a postharvest approach for fruit to meet the consumer's demand for diverse tastes and health promoting effects.

Modifications of cell wall pectin in chilling-injured 'Friar' plum fruit subjected to intermediate storage temperatures.

'Friar' plum (Prunus salicina Lindl.) fruit were stored at low (0°C), intermediate (5 and 15°C) and ambient temperature (25°C). Flesh translucency was evidenced as the main chilling injury (CI) symptom and the CI developed rapidly at 5 and 15°C but suppressed at 0°C. Modifications of cell wall pectin in 'Friar' plums were investigated during storage. Sodium carbonate-soluble pectin (SSP) was found to be predominant in the fruit but it decreased more rapidly at 5 and 15°C than 0°C. Nevertheless, SSP possessed abundant galactose, arabinose and rhamnose at 5 and 15°C. Nanostructural observations indicated that the detachment and degradation of linear backbone chains in SSP molecules were enhanced at 5 and 15°C. Therefore, the development of CI of 'Friar' plums at intermediate temperatures was associated with the modifications of SSP in the cell wall pectin of the fruit subjected to chilling stress.

Effect of high-hydrostatic pressure and moderate-intensity pulsed electric field on plum.

Moderate intensity pulse electric fields were applied in plum with the aim to increase bioactive compounds content of the fruit, while high-hydrostatic pressure was applied to preserve the purées. High-hydrostatic pressure treatment was compared with an equivalent thermal treatment. The addition of ascorbic acid during purée manufacture was also evaluated. The main objective of this study was to assess the effects on microorganisms, polyphenoloxidase, color and bioactive compounds of high-hydrostatic pressure, or thermal-processed plum purées made of moderate intensity pulse electric field-treated or no-moderate intensity pulse electric field-treated plums, after processing during storage. The application of moderate intensity pulse electric field to plums slightly increased the levels of anthocyanins and the antioxidant activity of purées. The application of Hydrostatic-high pressure (HHP) increased the levels of bioactive compounds in purées, while the thermal treatment preserved better the color during storage. The addition of ascorbic acid during the manufacture of plum purée was an important factor for the final quality of purées. The color and the bioactive compounds content were better preserved in purées with ascorbic acid. The no inactivation of polyphenoloxidase enzyme with treatments applied in this study affected the stability purées. Probably more intense treatments conditions (high-hydrostatic pressure and thermal treatment) would be necessary to reach better quality and shelf life during storage.

Preharvest treatments with salicylates enhance nutrient and antioxidant compounds in plum at harvest and after storage.

BACKGROUND: Previous reports have addressed the effectiveness of salicylic acid (SA), acetylsalicylic acid (ASA) and methylsalicylate (MeSA) postharvest treatments on maintaining quality properties during storage in several commodities. However, there is no literature regarding the effect of preharvest treatments with salicylates on plum quality attributes (at harvest or after long-term cold storage), which was evaluated in this research. RESULTS: At harvest, weight, firmness, individual organic acids, sugars, phenolics, anthocyanins and total carotenoids were found at higher levels in plums from SA-, ASA- and MeSA-treated trees than in those from controls. During storage, softening, colour changes and acidity losses were delayed in treated fruits as compared to controls. In addition, organic acids and antioxidant compounds were still found at higher levels in treated than in control plums after 40 days of storage. Results show a delay in the postharvest ripening process due to salicylate treatments, which could be attributed to their effect in delaying and decreasing ethylene production. CONCLUSION: Preharvest treatment with salicylates could be a safety, eco-friendly and new tool to improve (at harvest) and maintain (during storage) plum quality and especially its content of bioactive compounds with antioxidant properties, increasing the health effects of plum consumption. © 2017 Society of Chemical Industry.

Sugar metabolism reprogramming in a non-climacteric bud mutant of a climacteric plum fruit during development on the tree.

We investigated sugar metabolism in leaves and fruits of two Japanese plum (Prunus salicina Lindl.) cultivars, the climacteric Santa Rosa and its bud sport mutant the non-climacteric Sweet Miriam, during development on the tree. We previously characterized differences between the two cultivars. Here, we identified key sugar metabolic pathways. Pearson coefficient correlations of metabolomics and transcriptomic data and weighted gene co-expression network analysis (WGCNA) of RNA sequencing (RNA-Seq) data allowed the identification of 11 key sugar metabolism-associated genes: sucrose synthase, sucrose phosphate synthase, cytosolic invertase, vacuolar invertase, invertase inhibitor, α-galactosidase, ß-galactosidase, galactokinase, trehalase, galactinol synthase, and raffinose synthase. These pathways were further assessed and validated through the biochemical characterization of the gene products and with metabolite analysis. Our results demonstrated the reprogramming of sugar metabolism in both leaves and fruits in the non-climacteric plum, which displayed a shift towards increased sorbitol synthesis. Climacteric and non-climacteric fruits showed differences in their UDP-galactose metabolism towards the production of galactose and raffinose, respectively. The higher content of galactinol, myo-inositol, raffinose, and trehalose in the non-climacteric fruits could improve the ability of the fruits to cope with the oxidative processes associated with fruit ripening. Overall, our results support a relationship between sugar metabolism, ethylene, and ripening behavior.

Evaluation of Food Lures for Capture and Monitoring of Anastrepha fraterculus (Diptera: Tephritidae) on Temperate Fruit Trees.

The Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) is the main pest of fruit trees grown in temperate climates in the southern region of Brazil. The objective of this work was to evaluate the efficiency of the major commercial food lures used in Brazil for trapping and monitoring of A. fraterculus in plum, pear, and feijoa orchards. The assessed lures were hydrolyzed proteins of animal origin (CeraTrap) and plant origin (BioAnastrepha), torula yeast + borax (Torula), and grape juice. Response variables included the rate of adult capture (flies per trap per day, FTD) and the percentage of females captured. We also evaluated the number of times the weekly capture rate exceeded the traditional threshold of 0.5 FTD for each lure. Traps baited with grape juice, currently used for monitoring A. fraterculus in Southern Brazil, captured fewer adults and a lower percentage of females compared with the other lures. CeraTrap trapped a greater number of A. fraterculus adults and, in some cases, a lower percentage of females compared with the other lures in pears. Traps baited with CeraTrap had greater capture rates (FTD), particularly during the stages of fruit maturation and harvest, and even in years with low population density of A. fraterculus, thus demonstrating greater sensitivity in the detection of this pest. These results show that, in order to detect and monitor the presence of A. fraterculus in plum, feijoa, and pear crops, protein-based lures are superior to grape juice, especially the animal protein CeraTrap.

Plum Fruit Development Occurs via Gibberellin-Sensitive and -Insensitive DELLA Repressors.

Fruit growth depends on highly coordinated hormonal activities. The phytohormone gibberellin (GA) promotes growth by triggering degradation of the growth-repressing DELLA proteins; however, the extent to which such proteins contribute to GA-mediated fruit development remains to be clarified. Three new plum genes encoding DELLA proteins, PslGAI, PslRGL and PslRGA were isolated and functionally characterized. Analysis of expression profile during fruit development suggested that PslDELLA are transcriptionally regulated during flower and fruit ontogeny with potential positive regulation by GA and ethylene, depending on organ and developmental stage. PslGAI and PslRGL deduced proteins contain all domains present in typical DELLA proteins. However, PslRGA exhibited a degenerated DELLA domain and subsequently lacks in GID1-DELLA interaction property. PslDELLA-overexpression in WT Arabidopsis caused dramatic disruption in overall growth including root length, stem elongation, plant architecture, flower structure, fertility, and considerable retardation in development due to dramatic distortion in GA-metabolic pathway. GA treatment enhanced PslGAI/PslRGL interaction with PslGID1 receptors, causing protein destabilization and relief of growth-restraining effect. By contrast, PslRGA protein was not degraded by GA due to its inability to interact with PslGID1. Relative to other PslDELLA-mutants, PslRGA-plants displayed stronger constitutive repressive growth that was irreversible by GA application. The present results describe additional complexities in GA-signalling during plum fruit development, which may be particularly important to optimize successful reproductive growth.

Analysis of anthocyanin biosynthesis genes expression profiles in contrasting cultivars of Japanese plum (Prunus salicina L.) during fruit development.

Flavonoids are responsible of different fruit sensorial properties. In Japanese plum (Prunus salicina L.) these compounds are variable in both type and quantity during the different stages of fruit growth and maturation. Here we present the first study which determines the expression profile of structural genes of the flavonoid pathway and accumulation profiles of total phenols, proanthocyanidins and anthocyanins during fruit development stages in contrasting cultivars in Japanese plum. The biosynthesis of these compounds is differentially regulated in different tissues and cultivars. Our result showed that all pigmented tissues increased the expression of the leucoanthocyanidin dioxygenase (LDOX) gene, while all tissues without anthocyanin accumulation presented a minimal expression of LDOX. In addition, the regulation of putative transcription factors PsMYB10 and PsMYB1 were correlated positively and negatively with the pigmented tissues respectively, suggesting a critical and coordinated mechanism involved in the change of the fruit color.

Transformation of plum plants with a cytosolic ascorbate peroxidase transgene leads to enhanced water stress tolerance.

BACKGROUND AND AIMS: Water deficit is the most serious environmental factor limiting agricultural production. In this work, the tolerance to water stress (WS) of transgenic plum lines harbouring transgenes encoding cytosolic antioxidant enzymes was studied, with the aim of achieving the durable resistance of commercial plum trees. METHODS: The acclimatization process was successful for two transgenic lines: line C3-1, co-expressing superoxide dismutase (two copies) and ascorbate peroxidase (one copy) transgenes simultaneously; and line J8-1, harbouring four copies of the cytosolic ascorbate peroxidase gene (cytapx). Plant water relations, chlorophyll fluorescence and the levels of antioxidant enzymes were analysed in both lines submitted to moderate (7 d) and severe (15 d) WS conditions. Additionally, in line J8-1, showing the best response in terms of stress tolerance, a proteomic analysis and determination of the relative gene expression of two stress-responsive genes were carried out. KEY RESULTS: Line J8-1 exhibited an enhanced stress tolerance that correlated with better photosynthetic performance and a tighter control of water-use efficiency. Furthermore, this WS tolerance also correlated with a higher enzymatic antioxidant capacity than wild-type (WT) and line C3-1 plum plants. On the other hand, line C3-1 displayed an intermediate phenotype between WT plants and line J8-1 in terms of WS tolerance. Under severe WS, the tolerance displayed by J8-1 plants could be due to an enhanced capacity to cope with drought-induced oxidative stress. Moreover, proteomic analysis revealed differences between WT and J8-1 plants, mainly in terms of the abundance of proteins related to carbohydrate metabolism, photosynthesis, antioxidant defences and protein fate. CONCLUSIONS: The transformation of plum plants with cytapx has a profound effect at the physiological, biochemical, proteomic and genetic levels, enhancing WS tolerance. Although further experiments under field conditions will be required, it is proposed that J8-1 plants would be an interesting Prunus rootstock for coping with climate change.

Overexpression of plum auxin receptor PslTIR1 in tomato alters plant growth, fruit development and fruit shelf-life characteristics.

BACKGROUND: TIR1-like proteins are F-box auxin receptors. Auxin binding to the F-box receptor proteins promotes the formation of SCF(TIR1) ubiquitin ligase complex that targets the auxin repressors, Aux/IAAs, for degradation via the ubiquitin/26S proteasome pathway. The release of auxin response factors (ARFs) from their Aux/IAA partners allows ARFs to mediate auxin-responsive changes in downstream gene transcription. In an attempt to understand the potential role of auxin during fruit development, a plum auxin receptor, PslTIR1, has previously been characterized at the cellular, biochemical and molecular levels, but the biological significance of this protein is still lacking. In the present study, tomato (Solanum lycopersicum) was used as a model to investigate the phenotypic and molecular changes associated with the overexpression of PslTIR1. RESULTS: The findings of the present study highlighted the critical role of PslTIR1 as positive regulator of auxin-signalling in coordinating the development of leaves and fruits. This was manifested by the entire leaf morphology of transgenic tomato plants compared to the wild-type compound leaf patterning. Moreover, transgenic plants produced parthenocarpic fruits, a characteristic property of auxin hypersensitivity. The autocatalytic ethylene production associated with the ripening of climacteric fruits was not significantly altered in transgenic tomato fruits. Nevertheless, the fruit shelf-life characteristics were affected by transgene presence, mainly through enhancing fruit softening rate. The short shelf-life of transgenic tomatoes was associated with dramatic upregulation of several genes encoding proteins involved in cell-wall degradation, which determine fruit softening and subsequent fruit shelf-life. CONCLUSIONS: The present study sheds light into the involvement of PslTIR1 in regulating leaf morphology, fruit development and fruit softening-associated ripening, but not autocatalytic ethylene production. The results demonstrate that auxin accelerates fruit softening independently of ethylene action and this is probably mediated through the upregulation of many cell-wall metabolism genes.

Effect of Organic and Conventional Management on Bio-Functional Quality of Thirteen Plum Cultivars (Prunus salicina Lindl.).

In this study, thirteen Japanese plum cultivars (Prunus salicina Lindl.) grown under conventional and organic conditions were compared to evaluate the influence of the culture system on bioactive compounds. Their organic acids content (malic, citric, tartaric, succinic, shikimic, ascorbic and fumaric acid), total polyphenols, total anthocyanins, total carotenoids and antioxidant capacity (FRAP, ABTS) were evaluated. The study was performed during two consecutive seasons (2012 and 2013) in two experimental orchards located at the IFAPA centre Las Torres-Tomejil (Seville, SW Spain). The culture system affected all the studied parameters except for total carotenoid content. The organic plums had significantly higher polyphenol and anthocyanin concentrations and a greater antioxidant capacity. Additionally, significant differences between cultivars were also found. 'Showtime' and 'Friar' were the cultivars with the highest polyphenol concentration and antioxidant capacity. 'Black Amber' had the highest anthocyanin content and 'Larry Ann' and 'Songold' the highest carotenoid content. 'Sapphire' and 'Black amber' were the cultivars with the highest concentration of ascorbic acid. Our results showed a strong year effect. In conclusion, organic management had an impact on the production of phytochemical compounds in plums.