Deciphering serotonin's functional role in postharvest: Fruit-specific preservation of red fruit quality.

In order to establish a rapid and sensitive LAMP visual detection method for Cherry Virus A on-site, this study used the conserved fragment of the CVA coat protein (CP) sequence as a template for primer design. The rapid visual LAMP detection method for Cherry Virus A was successfully established by optimizing the reaction system components (concentration ratio of internal and external primers, and concentrations of loop primers, Bst DNA, Mg2+, dNTPs and betaine) and reaction conditions (temperature and time). This method enables specific detection of Cherry Virus A and facilitates visual inspection of crude nucleic acid extracts within 40 min, significantly reducing the diagnostic turnaround time. The limit of detection is 67.54 pg μL−1 (cDNA), which is 100 times more sensitive than PCR. Analysis of 70 field sweet cherry samples revealed an RT-LAMP positivity rate of 91.42%, significantly surpassing the 71.42% achieved by RT-PCR. This method is suitable for the rapid on-site detection of Cherry Virus, and can also provide a theoretical reference for the early diagnosis of cherry viral diseases.

The rising global threat of antimicrobial resistance has accelerated the search for effective natural antimicrobials. Fruit vinegars, traditionally valued for their potential therapeutic properties, are promising candidates; however, the specific phytochemical composition and antimicrobial efficacy of vinegars derived from Phoenix dactylifera (date) and Prunus avium (cherry) remain underexplored. This study aimed to characterize the phytochemical profiles and evaluate the antimicrobial potential of vinegars produced from these fruits. Yeast and acetic acid bacteria were isolated from spoiled fruit samples and characterized using standard microbiological techniques. Vinegar was produced via submerged fermentation of the extracted fruit musts. The physicochemical properties, nutrient content, and phytochemical constituents were analyzed using gravimetric and instrumental methods. In vitro antimicrobial activity was assessed against Staphylococcus aureus, Escherichia coli, Salmonella enterica serovar Typhi, and Candida albicans. Data were analyzed using Analysis of Variance (ANOVA) and post-hoc Tukey’s test at a 95% confidence level. Phytochemical screening confirmed the presence of alkaloids, saponins, flavonoids, tannins, and glycosides in both vinegar samples, fermented using Saccharomyces cerevisiae strain SR 128 and Acetobacter aceti strain WI. The vinegars demonstrated significant (p < 0.05) inhibitory activity against all tested pathogens, with the most potent effect observed against E. coli. In conclusion, vinegars from Prunus avium (cherry) and Phoenix dactylifera (date) possess considerable phytochemical and antimicrobial properties, with date vinegar exhibiting marginally superior efficacy. Therefore, the prepared vinegar samples from PA and PD possessed significant phytochemical and antimicrobial properties, and the sample produced from PD was slightly better than the sample produced from PA.

High summer temperatures increasingly constrain sweet cherry production, yet field-validated assessments of rootstock resilience remain scarce. To fill this gap, this study presents a pioneering multidimensional evaluation of five widely used sweet cherry rootstocks (Gisela 6, Gisela 12, Krymsk 5, Colt, and Lanting) under prolonged natural heat stress. Morphological traits, leaf anatomical characteristics, antioxidant enzyme activities (SOD, CAT, POD), lipid peroxidation (MDA), phytohormones (ABA and JA), and osmotic regulators were assessed. Traits with high coefficients of variation, including POD activity, ABA, JA, and soluble protein content, were identified as sensitive indicators of heat stress. Lanting exhibited the strongest heat tolerance, characterized by thicker leaves, fewer heat-induced lesions, and enhanced antioxidant capacity, whereas Gisela 6 showed severe leaf abscission, elevated MDA and ABA accumulation, and the weakest defense capacity. Correlation analysis indicated that root sucker number was positively associated with SOD activity and soluble sugar content, suggesting a potential role of whole-plant carbon allocation in mitigating oxidative stress. Using the Entropy Weight–TOPSIS model, we provided a robust ranking that identifies Lanting and Colt as superior heat-resilient genotypes. The results provide a field-validated framework that bridges the gap between controlled-environment theory and practical orchard management, offering critical guidance for expanding sweet cherry cultivation into high-temperature regions.

The present study was carried out during 2022–2023 and 2023–2024 on “Gisela‐6” cherry rootstock with the aim to find out the most suitable propagation media for multiplication through stool layering. The experiment was laid out in randomized block design, comprising five propagation media treatments, viz., sawdust, cocopeat, soil + farm yard manure, vermicompost + cocopeat, and sawdust + sand + vermicompost, replicated five times. Results revealed that stoolings mounded with cocopeat significantly increased number of rooted stoolings (47.81%), number of main roots (92.68%), total root length (65.99%), plant height (77.03%) and diameter (46.10%) of shoot, fresh (88.22% and 24.67%) and dry weight (111.00% and 137.80%) of roots and shoots, respectively, and total plant biomass (145.19%) over control (soil + farm yard manure). The correlation studies between characteristics of mounding media and morphological characteristics of layers revealed that water holding capacity of propagation media had a positive and significant relationship with rooting percentage, number of rooted stools, fresh and dry weight of stool shoots, pH, and bulk density. The percentage of rooting was found to be significantly and positively correlated with proportion of graftable rootstocks, leaf area, number of leaves, height of stool shoot, and diameter of stool shoot. Thus, cocopeat was proved to be the most appropriate mounding media for propagation of “Gisela‐6” sweet cherry rootstock through stool layering.

In this study, L‒asparaginase production in several endophytic fungi was evaluated along with their L‒glutaminase and urease co-activities. The effect of L‒asparagine and different culture media on L-asparaginase production were also evaluated. Among the 62 investigated isolates, 49 isolates exhibited L‒asparaginase activity, and the maximum zone index (6.58) was observed in Cladosporium perangustum EL1. Evaluation of L‒glutaminase and urease co-activities in L‒asparaginase-positive isolates screened 19 isolates with no L‒glutaminase activity and four isolates with minimum urease production. L‒asparaginase activity was quantified in 12 selected isolates using the Nesslerization method. Cladosporium cladosporioides Kr5−2 exhibited the maximum L‒asparaginase activity (10.78 U mL-1). Alternaria brassicae C showed high L‒asparaginase activity (7.07 U mL-1) free of L‒glutaminase, and low urease co-activity (1.97 U mL-1). Assessment of the effect of L‒asparagine on L‒asparaginase activity showed that the enzyme is inducible and substrate-regulated. Evaluation of ten different culture media showed that all isolates were able to produce L‒asparaginase on Mineral salts agar and Citrate agar culture media. Also, Cerelose ammonium nitrate agar, Kuehner basal culture medium, and Piefer, Humphrey, and Acree culture medium inhibited L‒asparaginase production in the majority of the isolates. This is the first report of L‒asparaginase production by endophytic fungi isolated from Taxus baccata, Pistacia vera, Prunus avium, Prunus cerasus, and Punica granatum, as well as the investigation of their L‒glutaminase and urease co-activities. Among the evaluated culture media, Mineral salts agar and Citrate agar culture media are suggested here as alternate for MCD. Moreover, Alternaria brassicae C is recommended as a promising isolate for future commercial L‒asparaginase production.

In this study, L‒asparaginase production in several endophytic fungi was evaluated along with their L‒glutaminase and urease co-activities. The effect of L‒asparagine and different culture media on L-asparaginase production were also evaluated. Among the 62 investigated isolates, 49 isolates exhibited L‒asparaginase activity, and the maximum zone index (6.58) was observed in Cladosporium perangustum EL1. Evaluation of L‒glutaminase and urease co-activities in L‒asparaginase-positive isolates screened 19 isolates with no L‒glutaminase activity and four isolates with minimum urease production. L‒asparaginase activity was quantified in 12 selected isolates using the Nesslerization method. Cladosporium cladosporioides Kr5-2 exhibited the maximum L‒asparaginase activity (10.78 U mL-1). Alternaria brassicae C showed high L‒asparaginase activity (7.07 U mL-1) free of L‒glutaminase, and low urease co-activity (1.97 U mL-1). Assessment of the effect of L‒asparagine on L‒asparaginase activity showed that the enzyme is inducible and substrate-regulated. Evaluation of ten different culture media showed that all isolates were able to produce L‒asparaginase on Mineral salts agar and Citrate agar culture media. Also, Cerelose ammonium nitrate agar, Kuehner basal culture medium, and Piefer, Humphrey, and Acree culture medium inhibited L‒asparaginase production in the majority of the isolates. This is the first report of L‒asparaginase production by endophytic fungi isolated from Taxus baccata, Pistacia vera, Prunus avium, Prunus cerasus, and Punica granatum, as well as the investigation of their L‒glutaminase and urease co-activities. Among the evaluated culture media, Mineral salts agar and Citrate agar culture media are suggested here as alternate for MCD. Moreover, Alternaria brassicae C is recommended as a promising isolate for future commercial L‒asparaginase production.

Pseudomonas syringae pv. syringae (Pss) is an economically significant bacterial pathogen that causes canker in sweet cherry trees. In Chile, sweet cherry (Prunus avium L.) is a key crop whose exponential production growth has increased phytosanitary pressure. However, the genetic diversity and adaptive mechanisms of local Pss populations have remained poorly understood. This study characterized 41 Pss isolates from major Chilean production regions. Their genomes were sequenced and compared with 152 public genomes from the PG2 phylogenetic group. The analysis revealed a predominance of the PG2d subgroup among the Chilean isolates, with a population structure defined by at least 18 genomic clusters, some of which are exclusive to Chile. A characteristic feature of this entire PG2d subgroup is the presence of indole-3-acetic acid (IAA) synthesis genes (iaaM and iaaH). Furthermore, this subgroup displayed a marked increase in ancestral gene gain and loss events, indicating extensive remodeling of the shell genome and supporting a model of lineage-specific adaptive evolution. We also identified lineage-specific orthogroups, structural variants of the T-PAI pathogenicity island, and a differential distribution of Hop-type effector proteins. Furthermore, an extended copper resistance operon (cop and cus systems) was detected in a subset of strains, and a dominant lineage was found to have a dual i1-type of T6SS system. These findings highlight the local diversification of Pss in Chile, likely driven by agro-environmental pressures. This study provides crucial insights into the evolution, adaptation, and pathogenic potential of this important pathogen in a crop of high strategic value.

Although the ripening process of climacteric fruits is well-characterized, the regulatory mechanisms underlying ripening in non-climacteric fruits, such as sweet cherry, remain poorly understood. In this study, we present an extensive physiological, biochemical and transcriptomic analysis of pedicel and fruit tissues across 8 developmental stages in the late-maturing sweet cherry cultivar "Regina," providing a comprehensive map of tissue-specific gene expression dynamics during fruit ripening. Our data reveal widespread transcriptomic and metabolomic reprogramming, particularly in sugar metabolism within the pedicel, suggesting that cherry ripening may be partially regulated by pedicel-derived signals. Through integrative analysis, we identified key transcription factors (TFs), most notably PaWRKY57 and PaNAC29, as putative regulators of fruit development. Silencing the genes encoding these TFs at the color breaking stage in both the "Regina" and early-maturing "Carmen" cultivars resulted in delayed pigmentation and reduced fruit size. Subsequent transcriptomic and proteomic analysis of silenced fruit revealed several candidate downstream targets and regulatory networks specifically linked to anthocyanin biosynthesis. Levels of central metabolic components and major anthocyanins, particularly cyanidin glucoside and cyanidin rutinoside, were reduced alongside altered abscisic acid (ABA) levels following PaWRKY57 and PaNAC29 silencing. Furthermore, we demonstrate that PaWRKY57 and PaNAC29 interact with the promoter regions of dihydroflavonol4-reductase (PaDFR) and leucoanthocyanidin dioxygenase (PaLDOX), regulating flavonoid biosynthesis. Notably, PaNAC29 also binds to the promoters of PACLOBUTRAZOL RESISTANCE 6 (PaPRE6) and linoleate 9S-lipoxygenase 5 (PaLOX5), influencing the biosynthesis of ABA and aroma-related volatile compounds. This work provides insights into tissue-specific regulatory dynamics in sweet cherry, establishes a framework for non-climacteric fruit ripening, and identifies promising targets for improving cherry yield and fruit quality.

Genome-wide analysis of AP2/ERF genes in sweet cherry and functional characteristic of PavERF45 in response to cold stress.

Climate change is intensifying the simultaneous occurrence of biotic and abiotic stresses in fruit crops, but yet the molecular mechanisms underlying plant responses remain poorly understood. The physiological and transcriptomic responses of two sweet cherry (Prunus avium L.) cultivars, Santina and Bing, grafted onto Gisela 12, were investigated under single and combined stresses imposed by Pseudomonas syringae pv. syringae and water deficit. Although biomass, gas exchange, and hormone accumulation showed only minor changes, combined stress triggered distinct cultivar-dependent transcriptional reprogramming. The cultivar Bing exhibited a pronounced response with 4261 differentially expressed genes (DEGs), characterized by strong repression of photosynthetic processes and activation of defense- and hormone-related pathways. In contrast, the cultivar Santina showed a moderate response with 674 DEGs, primarily reinforcing structural and secondary metabolism. Cultivar-specific modulation of abscisic acid sensitivity was associated with the contrasting regulation of WRKY40 and Sin3-like repressors, despite comparable ABA levels. Strikingly, both cultivars upregulated the GIGANTEA gene, underscoring its role as a central regulatory hub linking circadian rhythm, stomatal function, and hormonal crosstalk under dual stress. Collectively, these results reveal non-additive, genotype-specific transcriptional strategies in sweet cherry trees, providing insights into stress integration in fruit trees and identifying regulatory genes that may inform breeding and management strategies for resilience under climate change.

Putrescine and spermidine preharvest treatments improve crop yield, resistance to rain-induced cracking and fruit quality traits in sweet cherries

Eco-inspired synthesis of silver nanoparticles from Prunus avium stems: Mechanistic insights into multifunctional biomedical activities

PavbHLH102 functions as a positive regulator of anthocyanin biosynthesis in sweet cherry fruit by targeting multiple key genes

Preparation of linalool microcapsules and its application on preservation and antifungal protection in postharvest sweet cherry.

Functional traits mediate plant-environment interactions, yet their plasticity and genetic variability remain poorly quantified in long-lived tree species. We examined provenance trial (common garden) data from one growing season of Quercus robur L. and Prunus avium L. across six sites spanning a ~2°C climate gradient to evaluate phenotypic plasticity and genetic differentiation in specific leaf area (SLA) and spring leaf-out, and their effects on growth. We applied mixed-effects models to separate provenance, family, and site effects, and to test trait-growth relationships under contrasting water availability and temperature conditions. Growth performance from planting to between 16 and 8 years of age, respectively, was primarily determined by site conditions (modeled as a trial random effect, which includes climate, soil, and other local factors), with SLA emerging as the most significant functional trait across both species. As for the functional traits themselves, P. avium showed modest provenance-level variation in both traits (R 2 ~ 7%), while in Q. robur only leaf-out varied (R 2 ~ 19%) across provenances and families, indicating in both cases the presence of genetic differentiation. Plasticity in SLA and leaf-out was detectable in response to climate variables but was generally small relative to inter-individual variability (plasticity explained < 10% of trait variance). In P. avium, however, leaf-out timing was strongly climate-sensitive, consistent with its role as a short-lived, pioneer species, whereas Q. robur (a long-lived, dominant species) showed weaker plastic responses but slightly higher genetic structuring of traits. For all traits studied, a large proportion of the observed trait differences cannot be explained by climate or genetics, indicating high levels of individual variability (R 2 ~ 70%). This high inter-individual variability, together with the modest but significant plasticity observed, suggests that the studied species possess the genetic potential (aided by plasticity) needed for acclimation and adaptation to climate change.

Rain cracking limits the production of sweet cherries wherever they are grown. Cracking occurs by the separation of neighboring cells along their cell walls (by cell:cell separation). The objectives were to identify the cell wall components involved in cell:cell adhesion using immunolabeling and monoclonal antibodies (mAbs) and digestion assays employing pectinases, hemicellulases, and a cellulase. The mAbs identified homogalacturonans (LM19 and LM20), arabinans (LM6), and (to a lesser extent) xyloglucans (LM25) in skin, parenchyma, xylem, and phloem. Galactan (LM5) occurred only in the phloem, and xylan/arabinoxylan (LM11) occurred only in the xylem. Digestion of parenchyma by polygalacturonase (PGase) increased with time and concentration. Throughout development, digestion was highest by galactanase (GALase), followed by PGase and pectate lyase (PLase). Digestion by the hemicellulases xylanase (XYLase), xyloglucanase (XGase), and mannanase (MANase) was lower. The lowest digestion was due to cellulase (CELase). Incubation in pectinases released more cells, protoplasts, and cell wall fragments than incubation in hemicellulases or CELase. Storage duration had no effect on the digestion of cell walls. Digestion of parenchyma by native enzymes from fruit juice was similar to that by purified enzymes. Boiling juice to destroy enzyme decreased digestion. Adding Ca reduced digestion by PGase. Extracting and complexing Ca by EGTA increased digestion. Across eight cultivars, GALase, PGase, and PLase digested more cell walls than hemicellulases or cellulase. Within pectinases, GALase, PGase, and PLase were equally effective in “Adriana”, whereas in “Kordia”, PGase was more effective than GALase and PLase. In “Flamengo Srim”, “Regina”, and “Staccato”, digestion by GALase, PGase, and PLase was low. We conclude that pectins are primarily responsible for cell:cell adhesion in sweet cherry fruit. Further studies should therefore explore the relationship between cell wall chemistry, Ca status, and cell:cell adhesion.

ABSTRACT Sweet cherry ( Prunus avium L.) is a highly perishable temperate fruit of significant commercial importance, particularly in the Himalayan belt of India, with Jammu and Kashmir contributing over 94% of national production. For canning and processing, grading is essential for uniform quality, consumer acceptance and market competitiveness. At present, cherry grading in India is being performed manually, which is labor intensive, inconsistent and inefficient. To address this limitation, a power‐operated cherry grader was designed and developed to evaluate its technical performance and economic feasibility. The grader was tested at nine combinations of feed rates (400–800 kg/h) and drum speeds (8–12 rpm), using “Double” cherry variety and the results were compared with the traditional manual method. The developed machine achieved the highest throughput capacity (660.22 kg/h), effective throughput capacity (651.31 kg/h) and grading efficiency (98.58%) at the operating combination of 800 kg/h feed rate and 12 rpm drum speed (F3R3). The grading error (1.42%), ungraded fruit percentage (0.82%) and fruit damage (0.31%) remained minimal, demonstrating high precision with negligible quality loss. In contrast, manual grading showed much lower efficiency (66.55%), higher grading error (33.45%) and excessive labor requirements (93.89 man‐hours/tonne). Economic evaluation revealed a benefit–cost ratio of 2.3, a break‐even point of 6897.7 kg and a payback period of 1165 operational hours, confirming its commercial viability. Overall, the developed cherry grader significantly reduced drudgery, improved grading uniformity and ensured economic profitability, making it a promising technology for large scale adoption in the cherry canning industry.

Spotted-wing Drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae), is a damaging insect pest of sweet cherry fruit worldwide including in the central valley of California where it was first reported as an economic pest in spring 2009. The aim of this field-based study was to assess the relationship of Brix level and skin firmness on D. suzukii oviposition and infestation in 4 commercially important sweet cherry cultivars: Bing, Black Tartarian, Brooks, and Rainier. Results of this field study found that both higher Brix values and lower skin firmness resulted in increased fruit infestation in all varieties, highlighting the importance of these factors in host susceptibility. Other potential factors are also discussed as they relate to D. suzukii fruit infestation. Implications of these findings are discussed as well as how they might be used in future D. suzukii management in sweet cherries.

New Zealand’s sweet cherry (Prunus avium) industry covers approximately 1150 ha (Statistics New Zealand 2022) and reached a record export value of NZ$124 million in the 2024/25 season. Canker diseases are an emerging concern in New Zealand cherry production, with increasing reports of wood-infecting fungi associated with tree decline and mortality. In December 2024, dark circinate perithecia were observed under the bark of approximately 8-10 five-year-old ‘Sentennial’® (SPC103) cherry trees distributed across consecutive rows within a single orchard block in a commercial Upright Fruiting Offshoot (UFO) orchard in Central Otago, New Zealand (-45.0510, 169.1700). The fruiting bodies were associated with trunk and branch cankers on wilted or declining trees. Wood sections from active canker margins were surface sterilised in 1% sodium hypochlorite, rinsed in sterile water, cut into 3-5 mm segments, plated onto streptomycin-amended (100 mg/L) potato dextrose agar (PDA) and incubated at 20–22 o C. After 10 days, red-pigmented colonies were consistently observed, and hyphal-tip cultures were prepared; all isolates showed identical morphology. Colonies incubated at 21 o C under black light were slow growing, initially flat and white to pale-yellow, turning orange to pale pink with a white border and reached colony diameters of 11 mm, 14 mm and 72 mm after 7, 10 and 21 days respectively. Mycelium was septate, red- to pink-pigmented; conidiophores short, with hyaline unbranched phialides and monophialidic condiogenous cells (7.8 to 10.8 µm x 0.9 to 1.9 µm); conidia were hyaline, allantoid and aseptate (3.9 to 5.8 µm x 0.9 to 2 µm). These morphological characteristics are consistent with Calosphaeria pulchella (Réblová et al. 2004; Trouillas et al. 2012). Two isolates (ICMP 24078 and CP24/13) were selected for molecular confirmation and were identified by sequencing the internal transcribed spacer (ITS) and ß-tubulin gene (TUB2) regions. Sequences were deposited in GenBank (accession nos. PX022374, PX056650, PX532316, PX548828). BLASTn analysis in GenBank showed 100% identity between the ITS (593/593 nucleotides) and TUB2 (491/491 and 461/461 nucleotides) regions for isolates ICMP 24078 and CP24/13 with the corresponding reference sequences of C. pulchella type strain CBS 115999 (NR_145357, KT716476). Concatenated phylogenetic analysis grouped ICMP 24078 and CP24/13 with other C. pulchella isolates, forming a well-supported clade. Pathogenicity testing was conducted on living, potted two-year-old cherry (SPC103/Sentennial) plants. On 24 November 2024, a 5-mm wound was created in the bark of the trunk with a cork borer and isolates ICMP 24078 and CP24/13 were each used to inoculate five trees with 5-mm mycelial plugs from 14-day-old cultures; five additional trees received a PDA plug as a control. The inoculated area was sealed with Parafilm® and plants were incubated in a shadehouse in Lincoln (-43.641, 172.476), without temperature or humidity control. After 166 days, the length of the vascular necrosis extending from the inoculation site was measured. Isolates ICMP 24078 and CP24/13 produced mean lesion lengths of 62.5 mm and 50.0 mm, respectively, both significantly greater than the control mean of 12.2 mm (ANOVA, Tukey’s HSD, p &lt; 0.05). Calosphaeria pulchella was successfully re-isolated from all inoculated stems but not from the control plants, fulfilling Koch’s postulates. Calosphaeria canker, caused by C. pulchella, is increasingly recognised as a significant pathogen of sweet cherry and other Prunus species globally (Gramaje et al. 2014; Grinbergs et al. 2023; Trouillas et al. 2024; Mitrev et al. 2025), with an expanding host range and geographic distribution. To our knowledge, this is the first report of C. pulchella from New Zealand, consistent with Réblová et al. (2004) who reported the species only from Europe. Further research and ongoing surveillance are needed to understand its potential impact on the New Zealand cherry industry.