Search Results (38)

The European plum (Prunus domestica L.) is a hexaploid species that is grown worldwide for its tasty fruits. Many pomological forms and varieties exist, and thus it is important for genebank curators, breeders, growers, and/or control authorities to distinguish them with certainty. The purpose of this study was to select and verify a set of simple sequence repeat (SSR) markers for reliable genotyping, and to optimize their use in a one-reaction format for easy routine practice. After testing 78 SSR markers from different diploid Prunus species, 8 SSR markers were selected, multiplexed, and successfully verified as being able to distinguish all 242 unique genotypes tested. The selected markers were relatively easily scored and highly heterogenic, giving more than 35 alleles/genotype on average. The allele atlas was created to become a valuable tool for allele calling that should lead to standardized and reliable genotyping results between laboratories. The population analysis confirmed high diversity of the Czech germplasm collection used. The kit was also successfully tested for diploid “plums” of various origins and interspecies hybrids, as these are sometimes phenotypically indistinguishable from hexaploid European plums. The one-tube approach substantially simplified the plum genotyping laboratory workflow, minimizes errors, and saves labor, time, and money. Full article

European plum (Prunus domestica) is among the most important stone fruits cultivated worldwide. However, its production is significantly affected by fungal brown rot disease, caused by Monilinia spp. pathogens, which threaten the crop throughout the entire vegetation period. This study aimed to visually assess brown rot resistance and susceptibility in European plum and to perform whole-genome sequencing (WGS) of selected cultivars and hybrids grown in Lithuania, with the goal of identifying candidate single-nucleotide polymorphisms (SNPs) associated with disease response. WGS was performed for 20 European plum cultivars and hybrids with known resistance or susceptibility profiles, generating over 1,4 million SNPs. These SNPs were filtered to identify genetic variants associated with brown rot disease. Three candidate SNPs were found to be significantly associated with disease response (located on chromosomes G5 and G8) and one linked to susceptibility (on chromosome G5). Identified SNPs were located in genes encoding alcohol dehydrogenase family enzymes (resistant cultivars, G5 chromosome) and beta-glucosidase family enzymes (variants found in both resistant and susceptible cultivars, G5 chromosome), which are important for plant biotic stress response. The findings of this study provide a valuable foundation for the development of molecular markers for identifying resistant and susceptible cultivars and may inform future European plum breeding programs. Full article

A novel primer (FaSt-R) targeting the Prunus-specific Falling Stone (FaSt) non-autonomous transposon was combined with start-codon-targeted (SCoT) primers to assess genetic diversity in 12 cultivars from six Prunus species and 28 cultivars of European plum. Compared to SCoT-only analyses, the SCoT–FaSt combination produced fewer total bands but a higher percentage of polymorphic bands, while maintaining comparable values for polymorphism information content, resolving power, gene diversity, and Shannon’s index. SCoT–FaSt markers generated bands across a broader size range, which made gel patterns less dense, enabling the more accurate detection of differentially amplified fragments. Neighbor-joining and principal component analyses confirmed that SCoT–FaSt markers provided sufficient phylogenetic resolution at both interspecific and intraspecific levels. The sequencing of 32 SCoT–FaSt amplicons revealed FaSt elements in 26 fragments, with SCoT primers preferentially annealing to GC-rich exonic and intergenic regions. Seventeen protein-coding and one RNA-coding gene were partially identified, with FaSt elements localized in UTRs and introns of genes with key physiological functions. Comparative analysis indicated a biased distribution of FaSt elements between the Cerasus and Prunus subgenera. In silico findings suggest that FaSt elements are more fragmented in cherry species, potentially contributing to subgeneric divergence. Overall, the SCoT–FaSt marker system is effective for evaluating Prunus genetic diversity, reconstructing phylogenetic relationships, and elucidating the genomic impact of an active Mutator-like transposon. Full article

The super high-density (SHD) production system has recently been introduced to the Chilean European plum (Prunus domestica L.) industry, but the potential of applying regulated deficit irrigation (RDI) in this system remains unexplored. As irrigation water availability in Chile has been strongly jeopardized by climate change, there is an urgent need to validate water-conserving practices in modern production systems. A field study was conducted in a commercial SHD European plum orchard (cv. French grafted on Rootpac-20 rootstock) for two consecutive seasons in Peralillo, O’Higgins Region, Chile. The objective of this study was to assess the impact of a late water deficit (LD) on water productivity, fruit quality, plant water relations, and soil microbiota. The results showed that implementing LD enhanced water productivity by 40% without compromising fresh and dry fruit quality. Moderate to severe water stress induced no changes in physiological parameters such as stomatal conductance and photochemical efficiency. Additionally, the LD treatment significantly reduced soil moisture but increased the abundance of certain groups of beneficial soil microbiota and fine roots. These results highlight the potential of LD as a viable water-conserving practice in modern SHD European plum orchards, particularly in regions facing water scarcity due to climate change. Full article

European plum production is affected by mostly harm Monilinia spp., causing full pathogen brown-rot infections. The plums are the susceptible to the Monilinia fructigena pathogen, which is the most common in Europe. This study aims to analyze the gene expression profiles and signaling pathways of the European plum, cv. Victoria, inoculated with the M. fructigena pathogen at 24, 48, and 72 h post inoculation. By transcriptome sequencing, the number of differentially expressed genes (DEGs) increased over time, with the highest number at 72 hpi, showing the tendency to involve more genes in the response to prolonged exposure to the pathogen. Pathogenesis-related (PR) family and mildew resistance locus O (MLO-like) proteins were expressed the most during plum response to the pathogen. The plum initiates complex defense responses by significantly activating 23 pathways according to Kyoto Encyclopedia of Genes and Genomes (KEGG). In this study, expressed genes over the infection were in response to stress, defense, cell death, and disease resistance. The findings of this study could be used as the basis for further research of markers linked to resistance or susceptibility to disease in plum hybrids at an early age, which will improve the plum breeding process. Full article

Monilinia spp., which causes brown rot, is one of the most damaging pathogens in stone fruits. Researchers are exploring epiphytic and endophytic microorganisms with the potential to suppress pathogens, control pathogenic microorganisms, and/or promote plant growth. In this study, microorganisms with antagonistic activity against three Monilinia species were isolated from plum orchard soil and plum fruits. Antagonism tests in vitro showed strong antagonistic properties of six strains of bacteria and two yeast-like fungi against M. fructigena, M. fructicola, and M. laxa, with growth inhibition from 45.5 to 84.6%. The antagonists were identified and characterized at the genetic level using whole genome sequencing (WGS). Genes involved in antibiotic resistance, virulence, secondary metabolite synthesis, and plant growth promotion were identified and characterized through genome mapping, gene prediction, and annotation. None of the microorganisms studied were predicted to be pathogenic to humans. The results of this study indicate that the bacteria Bacillus pumilus, B. velezensis, two strains of Lysinibacillus agricola, Pseudomonas chlororaphis isolated from stone fruit orchard soil, and the yeast-like fungus Aureobasidium pullulans, isolated from plums, are promising candidates for the biological control of Monilinia spp. Full article

This study investigated the impact of different ageing containers on the volatile composition and quality of Negroamaro wine, a key variety from Apulia, Italy. Seven vessel types were evaluated: traditional Apulian amphorae (ozza), five types of oak barrels (American oak, French oak, European oak, a French + European oak and a multi-wood mix) and glass bottles as the control. The impact of the vessels was evaluated after 6 months of ageing through the characterization of phenolic, volatile and sensory profiles. Amphorae allowed a specific evolution of the wine’s primary aromas, such as fruity and floral notes, while enhancing volatile compounds like furaneol, which contributed to caramel and red fruit nuances, and also 3-methyl-2,4-nonanedione, a key compound related to anise, plum and premature ageing, depending on its concentration. This container also demonstrated effectiveness in stabilizing anthocyanin–tannin complexes, supporting color stabilization. Oak barrels allowed different outcomes to be obtained in terms of color stabilization, volatile profile, aroma and astringency. French oak exhibited the highest phenolic and tannin levels, enhancing anthocyanin stabilization and color intensity. European oak followed closely, while American oak excelled in color stabilization, with tannins less reactive to polymers. Mixed wood barrels showed lower phenolic extraction and the best astringency evolution. Full article

The Japanese plum tree (Prunus salicina Lindl.) is mainly cultivated in temperate areas of China and some European countries. Certain amounts of wood (from pruning works) are generated every year from this crop of worldwide commercial significance. The main objective of this work was to value this agricultural woody residue, for which the chemical composition of pruning wood extracts from six Japanese plum cultivars was investigated, and the antiproliferative activity of extracts and pure phenolics present in those extracts was measured. For the chemical characterization, total phenolic content and DPPH radical-scavenging assays and HPLC‒DAD/ESI‒MS analyses were performed, with the procyanidin (−)-ent-epicatechin-(2α→O→7,4α→8)-epicatechin (5) and the propelargonidin (+)-epiafzelechin-(2β→O→7,4β→8)-epicatechin (7) being the major components of the wood extracts. Some quantitative differences were found among plum cultivars, and the content of proanthocyanidins ranged from 1.50 (cv. ‘Fortune’) to 4.44 (cv. ‘Showtime’) mg/g of dry wood. Regarding the antitumoral activity, eight wood extracts and four phenolic compounds were evaluated in MCF-7 cells after 48 h of induction, showing the wood extract from cv. ‘Songold’ and (‒)-annphenone (3), the best antiproliferative activity (IC₅₀: 424 μg/mL and 405 μg/mL, respectively). Full article

In order to ensure the long-term sustainability of the conservation process of Norwegian plum germplasm, as well as to enhance the possibility of its utilization, a central plum heritage cultivar collection was established in 2020. In this study, 40 plum accessions maintained at the Ullensvang plum heritage cultivar collection were genetically characterized using a set of nine microsatellite markers recently approved by the ECPGR Prunus working group. The obtained molecular data were used to investigate the genetic identity, diversity, and structure among the analyzed accessions. No redundancies were detected among the plum accessions, which is in stark contrast to the previous molecular study on plum samples collected through an on-farm inventory of Southern Norway. Furthermore, the obtained data indicate that the Ullensvang collection contains a significant genetic diversity of Norwegian plum germplasm, previously held in decentralized sites. With that in mind, this collection can certainly be considered for the role of the National Clonal Plum Germplasm Repository. The nine microsatellite markers, recommended by ECPGR, revealed a genetic structure not entirely tied to previously proposed pomological groups, possibly indicating a history of hybridization among members of the various groups. Full article

In instances of severe infestations, Nepticulidae larvae can inflict damage on cultivated plants. Previously, it was assumed that the Prunus-feeding Nepticulidae have continuous distribution from Europe to the neighboring Caucasus. During recent fieldwork in the Caucasus, leaf mines were found on plum trees that initially resembled those of Stigmella plagicolella (Stainton) in Europe. However, upon rearing the adults, significant differences emerged, leading to the hypothesis that a different Prunus-feeding species exists in the Caucasus; this challenges previous records in Western Asia. This paper presents the outcomes of our morphological, molecular, and statistical investigations, unveiling S. colchica sp. nov., a previously unknown potential plum-tree pest. Distinguished by male genitalia characteristics, the new species differs from S. plagicolella. The inter- and intraspecific divergences between S. colchica sp. nov. and S. plagicolella range from 3.5% to 6.02%. Moreover, the utilized delimitation algorithms reliably clustered two species separately, as does our mitotype network. A statistical analysis also shows a discernible trend between the leaf mines of S. colchica sp. nov. and S. plagicolella. This unexpected discovery not only documents a new potential pest, enhancing our understanding of the Caucasian fauna, but also contributes to the broader biological inventory. Full article

Black knot (BK) is a deadly disease of European (Prunus domestica) and Japanese (Prunus salicina) plums caused by the hemibiotrophic fungus Apiosporina morbosa. Generally, phytopathogens hamper the balance of primary defense phytohormones, such as salicylic acid (SA)–jasmonic acid (JA) balance, for disease progression. Thus, we quantified the important phytohormone titers in tissues of susceptible and resistant genotypes belonging to European and Japanese plums at five different time points. Our previous results suggested that auxin-cytokinins interplay driven by A. morbosa appeared to be vital in disease progression by hampering the plant defense system. Here, we further show that such hampering of disease progression is likely mediated by perturbance in SA, JA, and, to some extent, gibberellic acid. The results further indicate that SA and JA in plant defense are not always necessarily antagonistic as most of the studies suggest but can be different, especially in woody perennials. Together, our results suggest that the changes in phytohormone levels, especially in terms of SA and JA content due to BK infection and progression in plums, could be used as phytohormonal markers in the identification of BK-resistant cultivars. Full article

Black Knot (BK) is a deadly disease of European (Prunus domestics) and Japanese (Prunus salicina) plums caused by the hemibiotrophic fungus Apiosporina morbosa. After infection, the appearance of warty black knots indicates a phytohormonal imbalance in infected tissues. Based on this hypothesis, we quantified phytohormones such as indole-3-acetic acid, tryptophan, indoleamines (N-acetylserotonin, serotonin, and melatonin), and cytokinins (zeatin, 6-benzyladenine, and 2-isopentenyladenine) in temporally collected tissues of susceptible and resistant genotypes belonging to European and Japanese plums during of BK progression. The results suggested auxin-cytokinins interplay driven by A. morbosa appears to be vital in disease progression by hampering the plant defense system. Taken together, our results indicate the possibility of using the phytohormone profile as a biomarker for BK resistance in plums. Full article

Ecological farming is increasing worldwide, as more and more consumers prefer chemical-free fruits. As a result, ecological farming is becoming increasingly appealing to European farmers, including those in Romania. However, implementing an effective ecological phytosanitary program remains a challenge for farmers due to limited options and a lack of information about their effectiveness. Romania is a major producer of plums and ranks second in the world after China. Aphids are common pests of plum, and some species are vectors of the damaging Plum pox virus, and therefore require special attention regarding their control. Eight ecological products were tested both in the field and laboratory for a duration of three vegetative periods to determine their efficiency in aphid control. The effects of ecological products were compared with five chemical insecticides known to be effective against aphids. Observations were made 24 and 48 h after spraying. Two of the eight ecological products tested were proven to be efficient in aphid control, Ovipron Top and Prev-Am, with a mortality rate over 90%. The results indicate that these two ecological products are comparable in effectiveness to chemical insecticides and could be suitable candidates for both ecological and conventional treatment programs. Full article

The aim of this study was to find the chemical parameters for the differentiation of plum cultivars grown along the fjord areas of Western Norway and Eastern Norway, having specific agroclimatic conditions. Chemical analysis of the fruits confirmed the contents of 13 quantified elements, 22 sugar compounds, 11 organic acids, 19 phenolic compounds, and antioxidant activity in 68 plum cultivars. Dominated contents were noted for nitrogen (with the maximum mean value of 3.11%), potassium (8055.80 mg/kg), and phosphorous (7878.88 mg/kg). Averagely, the highest level of sugars was determined for glucose (244.46 g/kg), fructose (197.92 g/kg), sucrose (208.25 g/kg), and sorbitol (98.02 g/kg), organic acids for malic acid (24.06 g/kg), and for polyphenol compounds were 5-O-caffeoylquinic acid (66.31 mg/kg), and rutin (58.06 mg/kg). Applied principal component analysis has been useful for distinguishing the plum cultivars from three areas in Norway where copper, iron, potassium, magnesium, manganese, and sodium; sucrose, ribose, maltose, and raffinose; p-hydroxybenzoic acid, rutin, ferulic acid, kaempferol 7-O-glucoside, p-coumaric acid, and 5-O-caffeoylquinic acid were the most influential. In regard to human health and future breeding work that will have the aim to produce functional food with high health-related compounds, the plum cultivar ‘Mallard’ should be underlined due to the high level of elements, ‘Valor’ due to high sugar content, ‘Helgøyplomme’ due to content of organic acids, and ‘Diamond’ due to the content of phenolic compounds. Full article

Plum pox virus (PPV) infects Prunus trees across the globe, causing the serious Sharka disease. Breeding programs in the past 20 years have been successful, generating plum varieties hypersensitive to PPV that show resistance in the field. Recently, a single tree displaying typical PPV symptoms was detected in an orchard of resistant plums. The tree was eradicated, and infected material was propagated under controlled conditions to study the new PPV isolate. Performing overlapping PCR analysis, the viral sequence was reconstructed, cloned and tested for infectivity in different ‘Jojo’-based resistant plums. The results confirmed that the isolate, named PPV-D ‘Herrenberg’ (PPVD-H), was able to infect all these varieties. Analyses of chimeras between PPVD-H and a PPV-D standard isolate (PPVD) revealed that the NIa region of PPD-H, carrying three amino acid changes, was enough to break the resistance of these plums. Experiments with single and double mutants showed that all changes were essential to preserve the escaping phenotype. Additionally, one of the changes at the VPg-NIapro junction suggested the involvement of controlled endopeptidase cleavage in the viral response. Transient expression experiments in Nicotiana benthamiana confirmed that NIa cleavage in PPVD-H was reduced, compared to PPVD, linking the observed behavior to an NIa cleavage modulation. Full article