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Postharvest peaches undergo rapid soft ripening and are susceptible to fungal diseases, which often result in severe losses during storage. The peach epidermis contains trichomes that form a specific structure on the peach surface. However, the relationship between trichomes and postharvest disease and involved mechanisms has not been well studied. In this study, the removal of trichomes reduced the disease incidence of peach brown rot caused by Monilinia fructicola. Cryo-scanning electron microscope observations showed that the fungal hyphae were found attached to the surface of trichomes. The fungal and bacterial communities on the peach surface at 0 d and 6 d were obtained by amplicon sequencing technology. Fungal communities on the peach surface contained a total of 1089 amplicon sequence variants (ASVs), which were demarcated into eight fungal phyla, 25 classes, 66 orders, 137 families, and 228 genera. The bacterial communities contained 10,821 ASVs assigned to 25 phyla, 50 classes, 114 orders, 220 families, and 507 genera. Higher bacterial diversity than fungal diversity was recorded on the peach epidermis. Trichome removal changed the microbial diversity and community on the peach surface. Compared with peach epidermis samples, the peach epidermis excluded trichomes samples contained similar fungal alpha diversity but significantly lower bacterial diversity. Seventeen different fungal genera and twenty-eight different bacterial genera were identified between peach trichome and peach epidermis excluded trichomes samples. The fungal and bacterial diversity on the peach epidermis showed a decreasing trend during storage. Beta diversity analysis revealed that the microbial communities of the peach epidermis and trichomes show different change trends between 0 d and 6 d. Trichome removal decreased relative abundance of Monilinia spp. and increased relative abundance of potential yeast and bacterial biocontrol agents. This study suggested that trichomes might modulate the microbial communities on fruit surfaces, and trichome removal technology after harvest might be developed to control peach postharvest decay., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

A severe outbreak of rust disease was observed on Prunus species, P. persica (peach), P . persica var. nectarina (nectarine), and P . salicina (Japanese plum) cultivated in northern Thailand in the rainy season. Previous reports have identified the causal agents as Tranzschelia discolor and T . pruni - spinosae based on only morphological characteristics. Thus, the aim of this study was to identify rust fungi of Prunus spp. based on morphology and molecular analyses. Between May and July in 2020 and 2022, 18 isolates were collected from five areas in Chiang Mai and Chiang Rai provinces. Symptoms of rust consisted of cinnamon brown pustules of uredinia that were hypophyllous and visible as pale greenish to chlorotic yellowish angular spots on the upper leaf surfaces. Urediniospore shape, size, and color were similar to T. discolor . Molecular analysis of internal transcribed spacer (ITS) and partial 28S large subunit (LSU) region rRNA genes confirmed the isolates to be T . discolor . This is the first report of P. salicina as a host of T. discolor in Thailand., Competing Interests: The author(s) declare no conflict of interest.

Two intergenic spacers cpDNA barcoding regions were used to assess the genetic diversity and phylogenetic structure of a collection of 25 Prunus accessions. The trnH-psbA and trnL-trnF intergenic spacers were able to distinguish and identify only four Prunus species. The average aligned length was 316-352 bp and 701-756 bp for trnH-psbA and trnL-trnF, respectively. The overall evolutionary divergence was higher in trnH-psbA than trnL-trnF. The transition/transversion bias (R) recorded as 0.59 in trnL-trnF and 0.89 in trnH-psbA. The number of invariable sites, nucleotide diversity (Pi), and the average number of nucleotide differences (k) was higher in the trnH-psbA region. The trnL-trnF records was above the other region in the number of variable sites, number of singleton variable sites, and the parsimony informative sites. Phylogenetic relationships among the 25 accessions of Prunus species were investigated. Most of the different Prunus species clustered in a homogenized distribution in both regions, except for the plum (P. domestica) accession (African Rose) was assigned with the peach (P. persica) accessions. The two intergenic cpDNA trnH-psbA and trnL-trnF were able to distinguish and identify the four Prunus species accessions., (© 2022. The Author(s).)

Successive plantings of Prunus species produce suboptimal growth and yield in many California soils due to a poorly understood soilborne disease complex, Prunus replant disease (PRD). We explored the hypothesis that PRD is mediated by microbial taxa in roots of Nemaguard peach, a rootstock for almond and other stone fruits. In a greenhouse bioassay, portions of 10 replant soils were treated with fumigation or pasteurization or left untreated as a control before being planted with peach seedlings. Ten weeks after planting, seedlings were considered PRD-affected if their top fresh weights in the control were significantly reduced, compared to the weights in pasteurization and fumigation treatments; plants with equivalent top weights in all treatments were considered to be non-affected. The roots were washed from the soil, frozen, extracted for total DNA, and used for metabarcoding of rRNA gene amplicons from bacteria, fungi, and oomycetes. High-throughput amplicon sequencing revealed that root microbial community shifts resulted from preplant treatments, and specific taxa were associated with PRD induction among controls. Random forest (RF) analysis discriminated effectively between PRD-affected and non-affected root communities. Among the 30 RF top-ranked amplicon sequence variant (ASV) predictors, 26 were bacteria, two were oomycetes, and two were fungi. Among them, only Streptomyces scabiei, Steroidobacter denitrificans, Streptomyces bobili, and Pythium mamillatum had root abundances ≥5% that were either associated positively (former two ASVs) or negatively (latter two) with PRD. Thus, our findings were consistent with microbial mediation of PRD in roots and suggested taxa that may be involved in the mediation., Competing Interests: The authors have declared that no competing interests exist.

Non-specific lipid transfer proteins (LTPs), present in multiple plant foods and pollens, are the predominant allergen in peach allergy in the Mediterranean region and may induce life-threatening allergic reactions. Although reasonably studied in adults, LTP allergy has been rarely described in children, and to the best of the author's knowledge, natural tolerance development during childhood to this allergen has not been reported to date. The authors reported the case of a 21 month-old boy who presented urticaria and facial edema 15 minutes after eating a peach. Sensitization to peach LTP was confirmed by skin prick tests and specific IgE. At the age of 32 months, skin prick tests and specific IgE to peach LTP were negative, so a food challenge was performed. The child tolerated one medium-sized peach. Peach and peach-related fruits were reintroduced in the child's diet. The authors discuss the relevance of regular allergy workup and dietary recommendations in children with LTP allergy.

Productivity of fruit tree crops depends on the interaction between plant physiology, environmental conditions and agricultural practices. We develop a mechanistic model of fruit tree crops that reliable simulates the dynamics of variables of interest for growers and consequences of agricultural practices while relying on a minimal number of inputs and parameters. The temporal dynamics of carbon content in the different organs (i.e., shoots-S, roots-R and fruits-F) are the result of photosynthesis by S, nutrient supply by R, respiration by S, R and F, competition among different organs, photoperiod and initial system conditions partially controlled by cultural practices. We calibrate model parameters and evaluate model predictions using unpublished data from a peach (Prunus persica) experimental orchard with trees subjected to different levels of branch pruning and fruit thinning. Fiinally, we evaluate the consequences of different combinations of pruning and thinning intensities within a multi-criteria analysis. The predictions are in good agreement with the experimental measurements and for the different conditions (pruning and thinning). Our simulations indicate that thinning and pruning practices actually used by growers provide the best compromise between total shoot production, which impacts next year's abundance of shoots and fruits, and current year's fruit production in terms of quantity (yield) and quality (average fruit size). This suggests that growers are not only interested in maximizing current year's yield but also in its quality and its durability. The present work provides for modelers a system of equations based on acknowledged principles of plant science easily modifiable for different purposes. For horticulturists, it gives insights on the potentialities of pruning and thinning. For ecologists, it provides a transparent quantitative framework that can be coupled with biotic and abiotic stressors., (© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Extra-early nectarine cultivars such as 'VioWhite 5' could present a lack of organoleptic and nutritional quality. Heat treatments (HT) can be applied to improve their primary characteristics. In this experiment, control (non-treated), HT 1 (3 h; 45 °C) and HT 2 (2 h; 50 °C) were studied. Fruit were stored (10 days; 0 ± 0.5 °C; 90-95% RH) followed by a simulated retail sale period (3 days; 15 °C; 70-75% RH)., Results: HT fruit showed higher weight loss (2.76 ± 0.06% and 3.32 ± 0.01% for HT 1 and HT 2 , respectively; vs. 2.23 ± 0.14% for control) and lower firmness than control samples (28.88% and 21.67% less for HT 1 and HT 2 , respectively). HT treatments induced an increase in soluble solids content and a decrease in total acidity, which led to a better sensory quality. These changes were positively received by consumers. Total antioxidant capacity was enhanced by HT due to an increase in phenolic compound content. A higher enzymatic activity was found in pectin methylesterase and polygaracturonase in HT nectarines when compared to control., Conclusion: The application of HT on extra-early nectarine cv. demonstrated a strong potential to improve consumption quality in the industry. © 2017 Society of Chemical Industry., (© 2017 Society of Chemical Industry.)

Background: Sugars and antioxidants in peaches contribute to fresh fruit quality and nutrition; however, information on widely grown cultivars and changes induced after peach jam preparation is limited. In the present study, colour, sugars and antioxidant parameters were determined in fruit and jam from 45 peach and nectarine cultivars., Results: Pronounced varietal differences were found in sorbitol (42-fold range), total phenolics (TPs) and antioxidant capacities (10- to 19-fold range). Sorbitol levels were greater in non-melting peach, followed by nectarine, and lower values were found in melting peach cultivars. Late-harvested peach and nectarine cultivars tended to have a higher soluble solid content and antioxidant potential. Cultivars with relatively high antioxidant contents produced darker and redder jams, containing more antioxidants, than the jam or the fruit from the other cultivars. Jam-TPs were reduced by 48% compared to fruit-TPs, with greater reduction being noted in high antioxidant cultivars. The most favorable jam organoleptic characteristics were found in 'Morsiani 90', 'Amiga', 'Romea' and 'Alirosada', as well as in non-melting compared to melting peach cultivars., Conclusion: The best cultivars for each fruit flesh type and jam were identified. Peach jam could be an alternative substitute when fresh fruit is not available and when it is prepared with high antioxidant cultivars. © 2016 Society of Chemical Industry., (© 2016 Society of Chemical Industry.)

The purpose of this study was to determine the fine-scale genetic structure of populations of the brown rot pathogen Monilinia fructicola within individual peach tree canopies to better understand within-tree plant pathogen diversity and to complement previous work on spatiotemporal development of brown rot disease at the canopy level. Across 3 years in a total of six trees, we monitored disease development, collected isolates from every M. fructicola symptom during the course of the season, and created high-resolution three-dimensional maps of all symptom and isolate locations within individual canopies using an electromagnetic digitizer. Each canopy population (65 to 173 isolates per tree) was characterized using a set of 13 microsatellite markers and analyzed for evidence of spatial genetic autocorrelation among isolates during the epidemic phase of the disease. Results showed high genetic diversity (average uh=0.529) and high genotypic diversity (average D=0.928) within canopies. The percentage of unique multilocus genotypes within trees was greater for blossom blight isolates (78.2%) than for fruit rot isolates (51.3%), indicating a greater contribution of clonal reproduction during the preharvest epidemic. For fruit rot isolates, between 54.2 and 81.7% of isolates were contained in one to four dominant clonal genotypes per tree having at least 10 members. All six fruit rot populations showed positive and significant spatial genetic autocorrelation for distance classes between 0.37 and 1.48 m. Despite high levels of within-tree pathogen diversity, the contribution of locally available inoculum combined with short-distance dispersal is likely the main factor generating clonal population foci and associated spatial genetic clustering within trees.

Exclusion cages were used to compare the incidence and severity of feeding injury from brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), on 'Redhaven' peaches, 'Golden Delicious' apples, and 'Smoothee Golden' apples at harvest, following sequential periods of exposure to natural H. halys populations during the 2011 and 2012 growing seasons in Virginia. The fruit used in these experiments were in orchards or on trees that were not managed for H. halys. Treatments were sets of 50 fruit that were always caged, never caged, or exposed during one interval during the fruiting period of peaches and apples in the Mid-Atlantic region of the United States. The cages effectively prevented feeding injury from H. halys. Peaches and apples that were never caged showed the highest percentages of injured fruit at harvest. Exposure treatment had a significant effect on the percentage of fruit showing external injury at harvest in both years for apples and in 2012 for peaches, and a significant effect on the percentage of apples and peaches showing internal injury at harvest in both years. There was no consistent effect of each exposure period on peach injury, but apples exposed during the mid- to latter portion of the season tended to show most injury. Across all exposure periods, more internal than external injuries were recorded at harvest from peaches, while apples tended to have equal or very similar numbers of both kinds of injury. The implications of these results to H. halys management in eastern apple orchards are discussed., (© The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Polyphenolic extracts and fractions of selected peach and plum genotypes were evaluated for cell viability and antiproliferation activity in vitro against an estrogen independent MDA-MB-435 and estrogen dependent MCF-7 breast cancer cell lines and one non-cancerous breast line MCF-10A. All extracts showed a phenolic dose-dependent cytotoxic effect against MDA-MB-435, weak activity against MCF-7 and small or no activity against MCF-10A. Genotype phenolic profiles showed varying degrees of polyphenolic mixtures. Fractionation of peach BY00P6653 extracts gave 4 fractions, with fraction F-I (caffeic acid derivatives) showing a strong activity against MDA-MB-435 followed by fraction F-II (anthocyanins). Induced-apoptosis by F-I on MDA-MB-435 was confirmed by Tunnel nuclear staining of cells with apoptotic DNA fragmentation (0-100 μg/mL) with no effects in normal cells (0-200 μg/mL). Selected stone fruit genotypes can be added to the list of fruits with cytotoxic effects against breast cancer cells while not affecting normal cells., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

In the present study we have evaluated the antioxidant activities of different fractions (hexane, ethyl acetate, n-butanol and aqueous fractions) of Prunus persica fruit. For extraction simple warring blender method was employed and total phenolic and flavonoid contents were correlated with different antioxidant activities (total antioxidant, 2,2-diphenyl-1-picrylhydrazyl (DPPH), H2O2 scavenging, superoxide radical scavenging, iron chelating and their reducing power properties). Different in vitro antioxidant studies showed that ethyl acetate and n-butanol fractions had the maximum activities that were well correlated with total phenolic and flavonoid contents. Maximum yield (25.14±2.2%) was obtained in its aqueous fraction. Both ethyl acetate and n-butanol fractions showed significant inhibitory effects on different antioxidant activities. A significantly high correlation coefficient existed between total antioxidant activities and with total phenolic as well as total flavonoid contents. It appears that ethyl acetate and n-butanol fractions of P. persica may serve as new potential sources of natural antioxidants and could be of therapeutic use in treating several diseases., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The aldo-keto reductase (AKR) superfamily is a large enzyme group of NADP-dependent oxidoreductases with numerous roles in metabolism, but many members in this superfamily remain uncharacterized. Here, PpAKR1, which was cloned from the rosaceous peach tree (Prunus persica), was investigated as a member of the superfamily. While PpAKR1 had amino acids that are important in AKRs and which belonged to the AKR4 group, PpAKR1 did not seem to belong to any of the AKR4 subgroups. PpAKR1 mRNA abundance increased with abscisic acid, oxidative stress, and cold and salt stress treatments in peach. NADP-dependent polyol dehydrogenase activity was increased in Arabidopsis thaliana transformed with PpAKR1. Salt tolerance increased in Arabidopsis transformed with PpAKR1. PpAKR1, which was a previously uncharacterized member of the AKR superfamily, could be involved in the abiotic stress tolerance., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Glucitol (Gol) is a major photosynthetic product in plants from the Rosaceae family. Herein we report the molecular cloning, heterologous expression and characterization of Gol dehydrogenase (GolDHase, EC 1.1.1.14) from peach (Prunus persica) fruits. The recombinant enzyme showed kinetic parameters similar to those reported for orthologous enzymes purified from apple and pear fruits. The activity of recombinant GolDHase was strongly inhibited by Cu(2+) and Hg(2+), suggesting that it might have cysteine residues critical for functionality. Oxidizing compounds (such as diamide, hydrogen peroxide and oxidized glutathione) inactivated the enzyme, whereas its activity was restored after incubation with reduced glutathione and thioredoxin from Escherichia coli. Recombinant thioredoxin h from peach fruits also recovered the activity of oxidized GolDHase. Our results suggest that peach fruit GolDHase could be redox regulated in vivo and this would be of relevance to determine carbon assimilation and partitioning in plants accumulating sugar alcohols., (© The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Peaches are highly perishable and deteriorate quickly at ambient temperature. Cold storage is commonly used to prevent fruit decay; however, it affects fruit quality causing physiological disorders collectively termed 'chilling injury' (CI). To prevent or ameliorate CI, heat treatment is often applied prior to cold storage. In the present work, metabolic profiling was performed to determine the metabolic dynamics associated with the induction of acquired CI tolerance in response to heat shock. 'Dixiland' peach fruits exposed to 39 °C, cold stored, or after a combined treatment of heat and cold, were compared with fruits ripening at 20 °C. Dramatic changes in the levels of compatible solutes such as galactinol and raffinose were observed, while amino acid precursors of the phenylpropanoid pathway were also modified due to the stress treatments, as was the polyamine putrescine. The observed responses towards temperature stress in peaches are composed of both common and specific response mechanisms to heat and cold, but also of more general adaptive responses that confer strategic advantages in adverse conditions such as biotic stresses. The identification of such key metabolites, which prime the fruit to cope with different stress situations, will likely greatly accelerate the design and the improvement of plant breeding programs., (© 2013 John Wiley & Sons Ltd.)

Flowering peach Prunus persica cv. Genpei bears pink and variegated flowers on a single tree. The structural genes involved in anthocyanin biosynthesis were expressed strongly in pink petals but only very weakly or not at all in variegated petals. A cDNA clone encoding a MYB-like gene, isolated from pink petals was strongly expressed only in pink petals. Introduction of this gene, via biolistics gave magenta spots in the white areas of variegated petals, therefore this gene was named as Peace (peach anthocyanin colour enhancement). Differences in Peace expression determine the pattern of flower colouration in flowering peach. The R2R3 DNA-binding domain of Peace is similar to those of other plant MYBs regulating anthocyanin biosynthesis. Key amino acids for tertiary structure and the motif for interaction with bHLH proteins were conserved in Peace. Phylogenetic analysis indicates that Peace is closely related to AtMYB123 (TT2), which regulates proanthocyanidin biosynthesis in Arabidopsis, and to anthocyanin regulators in monocots rather than to regulators in dicots. This is the first report that a TT2-like R2R3 MYB has been shown to regulate anthocyanin biosynthesis.

A ripening specific bZIP gene of peach was studied by ectopically expressing it in tomato. Two lines, with either a mild or a strong phenotype, respectively, were analyzed in detail. Transgenic fruit morphology was normal, yet the time spent to proceed through the various ripening stages was longer compared to wild type. In agreement with this finding the transgenic berries produced less ethylene, and also had a modified expression of some ripening-related genes that was particularly evident in berries with a strong phenotype. In particular, in the latter fruits polygalacturonase and lipoxygenase genes, but also genes coding for transcription factors (TFs) important for tomato ripening (i.e. TAGL1, CNR, APETALA2a, NOR) did not show the expected decreased expression in the red berries. As regards the RIN gene, its expression continued to increase in both mild and strong lines, and this is in agreement with the dilated ripening times. Interestingly, a metabolomic analysis of berries at various stages of ripening showed that the longer time spent by the transgenic berries to proceed from a stage to another was not due to a slackened metabolism. In fact, the differences in amount of stage-specific marker metabolites indicated that the transgenic berries had a very active metabolism. Therefore, the dilated ripening and the enhanced metabolism of the berries over-expressing the bZIP gene suggest that such gene might regulate ripening by acting as a pacemaker for some of the ripening metabolic pathways., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Trees are capable of tremendous architectural plasticity, allowing them to maximize their light exposure under highly competitive environments. One key component of tree architecture is the branch angle, yet little is known about the molecular basis for the spatial patterning of branches in trees. Here, we report the identification of a candidate gene for the br mutation in Prunus persica (peach) associated with vertically oriented growth of branches, referred to as 'pillar' or 'broomy'. Ppa010082, annotated as hypothetical protein in the peach genome sequence, was identified as a candidate gene for br using a next generation sequence-based mapping approach. Sequence similarity searches identified rice TAC1 (tiller angle control 1) as a putative ortholog, and we thus named it PpeTAC1. In monocots, TAC1 is known to lead to less compact growth by increasing the tiller angle. In Arabidopsis, an attac1 mutant showed more vertical branch growth angles, suggesting that the gene functions universally to promote the horizontal growth of branches. TAC1 genes belong to a gene family (here named IGT for a shared conserved motif) found in all plant genomes, consisting of two clades: one containing TAC1-like genes; the other containing LAZY1, which contains an EAR motif, and promotes vertical shoot growth in Oryza sativa (rice) and Arabidopsis through influencing polar auxin transport. The data suggest that IGT genes are ancient, and play conserved roles in determining shoot growth angles in plants. Understanding how IGT genes modulate branch angles will provide insights into how different architectural growth habits evolved in terrestrial plants., (© 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.)

CBF (C-repeat Binding Factor) transcription factors are part of the AP2/ERF (Apetala2-ethylene responsive factor) domain family of DNA-binding proteins that recognize a C-repeat response cis-acting element that regulates a number of cold-responsive genes (CBF regulon). Induction of CBF gene expression by low temperature in Arabidopsis has been shown to be gated by a circadian clock. In peach (Prunus persica L.), five CBF genes are arranged in tandem on scaffold (linkage group) 5 of the peach genome. Since CBF gene regulation has been shown to be more complex in woody plants than herbaceous plants, the present study was conducted to determine if temperature-modulated CBF gene expression in peach leaf and bark tissues was also influenced by a circadian clock. One-year-old 'Loring' peach trees grafted on 'Bailey' rootstocks were entrained to a 12-h day/12-h night photoperiod at 25 °C. After 2 weeks, trees were exposed to 4 °C under continuous light for up to 48 h beginning at either subjective dawn + 4 h (ZT4; where ZT is Zeitgeber time) or subjective dawn + 16 h (ZT16) with leaf and bark tissues harvested at various time points. Gene expression of the five peach CBF genes and a DREB2 gene was assessed by real-time quantitative polymerase chain reaction. Results revealed a distinct gating of CBF gene expression by a circadian clock for four CBF genes in both leaf and bark tissues. CBF genes were highly induced by 4 °C in ZT4 leaf samples with expression peaking at 6-24 h depending on the specific CBF gene. In contrast, CBF gene expression was highly attenuated in leaf, and to a lesser extent in bark, samples exposed to 4 °C at ZT16. These results are similar to reports for Arabidopsis. Further experiments were conducted to verify environmental influence on the induction of CBF and DREB2 genes. In contrast to DREB2 genes from other dicots, the peach DREB2 ortholog was induced by both low temperature and dehydration. Induction of the peach CBFs and DREB2 by either low temperature or dehydration corresponded with regulatory motifs present in their promoter sequences. Low temperature and dehydration induction data for three peach dehydrin genes indicated that the regulation of these genes in peach is complex, with individual dehydrin gene expression being correlated with the expression of one or more CBF genes.

WRKY transcription factors play key roles in plant resistance to various stresses, but their roles in fruit ripening remain largely unknown. Here, we report a WRKY gene PpWRKY14 involved in the regulation of fruit ripening in peach. The expression of PpWRKY14 showed an increasing trend throughout fruit development. PpWRKY14 was a target gene of PpNAC1, a master regulator of peach fruit ripening. PpWRKY14 could directly bind to the promoters of PpACS1 and PpACO1 to induce their expression, and this induction was greatly enhanced when PpWRKY14 formed a dimer with PpNAC1. However, the transcription of PpNAC1 could be directly suppressed by two EIN3/EIL1 genes, PpEIL2 and PpEIL3. The PpEIL2/3 genes were highly expressed at the early stages of fruit development, but their expression was programmed to decrease significantly during the ripening stage, thus derepressing the expression of PpNAC1. These results suggested a PpEIL2/3–PpNAC1–PpWRKY14 module that regulates fruit ripening by modulating ethylene production in peach. Our results provided an insight into the regulatory roles of EIN3/EIL1 and WRKY genes in fruit ripening. [ABSTRACT FROM AUTHOR]

As compared to conventional physical and chemical techniques, the biological method (green synthesis) is an economical, nontoxic, fast, eco-friendly and cost-effective technique that utilizes plant extract to generate highly stable and biocompatible nanoparticles. The existing study focuses on the synthesis of zinc sulphide nanoparticles (ZnS NPs) using P. persica leaf extract which is used as a reducing agent and their associated properties. The prepared samples were examined in terms of structural, optical, morphological and compositional properties. The SEM images showed the agglomerated spherical particles while XRD spectra confirmed the hexagonal (wurtzite) phase of synthesized ZnS samples with average crystallite sizes found to vary from 12.45 to 14.36 nm. The optical absorption spectra displayed the absorption peaks at 331 nm (4.26 eV) and 339 nm (4.10 eV). This blue shift in the absorption band suggests the formation of ZnS NPs compared with bulk ZnS (∼ 3. 6 8 eV) material. The FTIR peaks from 612– to 630 cm − 1 and 860– to 1022 cm − 1 are because of the symmetric bending vibrations of the Zn–S bands. Electrical measurements showed that the resistivity is found to be decreasing with increasing temperature, signifying the semiconducting behavior of the synthesized ZnS NPs. The findings of this study suggest the feasible use of P. persica leaves extract for the production of ZnS NPs which could be utilized as multifunctional material in medical applications, biosensors, photocatalytic and electrical applications. [ABSTRACT FROM AUTHOR]

The peach tree “Prunus persica” is widely cultivated in India, and its fruits which have been used for centuries in traditional Indian medicine, are also known as the Queen of the Fruits. Prunus persica has immense therapeutic potential, widespread use in folklore and ancient systems of medicine for its anti-urolithic and other medicinal properties, and is included in the Pashanbheda group of herbs mentioned in Ayurveda for the treatment of kidney stones. Moreover, with growing interest in phytopharmaceuticals in the present world, there always remains an urge for a comprehensive understanding of the phytochemicals responsible for the medicinal activity of herbal drugs, giving rise to the importance of conducting bioassay-guided fractionation. In this study, the anti-urolithiasis activity of different fractions of Prunus persica fruit extracts was evaluated via Nucleation, Aggregation, and Growth assays, and fraction III showed the highest effects in vitro. This study provides a pharmacological basis for using Prunus persica fruit extract in treating kidney stones. [ABSTRACT FROM AUTHOR]

The current study was performed on a 6-year-old "Florida" peach cultivar (Prunus persica) during 2022 and 2023 respectively. Twenty-four peach trees uniformly were selected and sprayed two times at the beginning of pit starts hardening and at the end of phase two of fruit growth with the following treatments: the control, glycine betaine at 400 mg l-1, potassium silicate at 200 mg l-1, potassium silicate at 400 mg l-1, potassium silicate at 200 mg l-1 + glycine betaine at 400 mg l-1, potassium silicate at 400 mg l-1 + glycine betaine at 400 mg l-1, proline at 400 mg l-1 and potassium silicate at 200 mg l-1 + proline at 400 mg l-1. The results indicated that both treatments of potassium silicate at 200 mg l-1 + proline at 400 mg l-1 and potassium silicate at 400 mg l-1 + glycine betaine at 400 mg l-1 resulted in a significant increase in concentrations of anthocyanin and total carotenoid contents in the skin. Moreover, total soluble solid, vitamin C and total soluble solid / acidity were shown with high concentrations as compared with the control. Overall, the use of potassium silicate at 200 mg l-1 + proline at 400 mg l-1 or potassium silicate at 400 mg l-1 + glycine betaine at 400 mg l-1 two times is recommended. [ABSTRACT FROM AUTHOR]

'BRS Sarau' is a highly productive peach cultivar widely adapted to the Southern and Southeast region of Brazil. It produces fruits of excellent flavor and shape, with attractive skin and flesh color, and its harvest starts near the Christmas holidays, when the demand for peaches is high. [ABSTRACT FROM AUTHOR]

Peaches are susceptible to various environmental stresses. Particularly in late spring, freezing temperatures can damage peaches and consequently, affect their productivity. Therefore, flowering delay is a prominent strategy for avoiding spring frost damage. Our previous study confirmed that treatment with 5% sodium alginate and 100 mM CaCl2 (5AG) to avoid frost damage during the blooming stage delays flowering. To reveal the flowering delay mechanism of peaches, this study systematically analyzed the modification of amino acid profiles in control and 5AG-treated peach plants at different day intervals. Our findings indicate that arginine (Arg), glutamate (Glu), and proline (Pro) levels differed between the control and 5AG-treated peach shoots throughout the phenological development of flower buds. Furthermore, two amino acids (Arg and Glu) are involved in the Pro pathway. Thus, using a computational metabolomics method, Pro biosynthesis and its characteristics, gene ontology, gene synteny, cis-regulatory elements, and gene organizations were examined to decipher the involvement of Pro metabolism in peach flowering delay. In addition, qRT-PCR analysis revealed the transcriptional regulation of Pro-related and flowering-responsive genes and their role in flowering delay. Overall, this pilot study provides new insights into the role of Pro in the flowering delay mechanisms in Prunus persica through 5AG treatment. [ABSTRACT FROM AUTHOR]

Climate change is affecting the production of temperate fruit crops. Freeze damage, particularly in spring, has resulted in significant economic losses in peach production in the southeastern United States. Research efforts in peach and other Prunus species have primarily focused on dormancy-related traits associated with bloom time, such as chill and heat requirement, with fruitlet freeze tolerance not equally represented. This study reports fruitlet freeze tolerance in 75 peach and nectarine accessions at six freezing temperatures (0 to −10 °C) using electrolyte leakage method over two seasons (2022–2023). Fruitlet freeze tolerance ranged from −3.9 to −10.2 °C with an estimated freeze damage ranging from 16–48% of fruitlet tissue with the majority of the accessions showing tolerance to cold temperatures in the −4 to −6 °C and 25–35% range. Variability in tolerance was noted across years, including some inconsistencies between tolerance group assignments. Grouping based on the estimated damage showed better stability and some accessions changed their grouping from the extremes to an intermediate tolerance group. Interestingly, nectarine accessions were among the most tolerant in both seasons. Broad-sense heritability of 0.52 and 0.85, estimated for freeze tolerance and % tissue damage, respectively, suggested genetic control of this trait with a potential for improvement via breeding. [ABSTRACT FROM AUTHOR]

Summer pruning is an important horticultural operation that is performed to manipulate tree response so as to make it better manageable without a reduction in yield and fruit quality. But the timing is also an important factor in performing this event. Keeping in view the above facts, the present investigation was carried out to elucidate the 'differential response of summer pruning timing on cropping behavior in low-chill peach cvs. Florida Prince and Shan-i-Punjab'. The experiment was carried out at the experimental orchard of the Department of Fruit Science, College of Horticulture and Forestry, Neri, Hamirpur (HP) during the years 2018–2019 and 2019–2020. There are six treatments in the experiment, each with four replications. T1: no pruning; T2: 25% summer pruning on July 10th + winter pruning (WP); T3: 25% summer pruning on July 20th +WP; T4: 25% summer pruning on July 30th +WP; T5: 25% summer pruning on August 10th +WP); and T6: standard winter pruning (SWP). According to the study's findings, combining 25% summer pruning on July 10th with winter pruning resulted in the greatest improvement in terms of vegetative, flowering or blooming, and qualitative parameters, namely fruit weight, fruit shape index, total soluble solid, and sugar content. However, Florida Prince showed positive enhancement of various characteristics and performed better than Shan-i-Punjab. [ABSTRACT FROM AUTHOR]

Class III peroxidases are plant-specific and play a key role in the response to biotic and abiotic stresses, as well as in plant growth and development. In this study, we investigated 60 POD genes from Prunus persica based on genomic and transcriptomic data available in NCBI and analysed the expression of individual genes with qPCR. Peroxidase genes were clustered into five subgroups using the phylogenetic analysis. Their exon–intron structure and conserved motifs were analysed. Analysis of the transcriptomic data showed that the expression of PpPOD genes varied significantly in different tissues, at different developmental stages and under different stress treatments. All genes were divided into low- and high-expressed genes, and the most highly expressed genes were identified for individual tissues (PpPOD12 and PpPOD42 in flower buds and PpPOD73, PpPOD12, PpPOD42, and PpPOD31 in fruits). The relationship between cold tolerance and the level of peroxidase expression was revealed. These studies were carried out for the first time in the peach and confirmed that chilling tolerance may be related to the specificity of antioxidant complex gene expression. [ABSTRACT FROM AUTHOR]

The research objective was to provide participatory actions by local actors for the production of Prunus persica L. (pêssego) in family orchards in the community of Surí, municipality of Guane. Three and six local stakeholders selected based on an intentional demonstration to discover their perception on the management and benefits of fruit trees. On the other hand, a pre-germination treatment (mechanical scarification) was carried out on 50 seeds, of which 42 seedlings were obtained in a micro nursery, subsequently transplanted to family orchards and their height was measured weekly for a month. The methods used for research are: Participatory Rapid Assessment, scientific and participatory measurement and observation. An in-depth interview and questionnaire form used to collect data from two actors. The most important results are: oil from local stakeholders to produce the species; strong points and bottles for your production; high percentage of seed germination; Plant the plants at the ideal height for transplanting after 33 days; The medium growth after transplanting for the first time was more than 4.5 cm per week. Foram elaborated actions for the production and handling of the species. Overall, it is concluded that local interested parties demonstrate great interest in producing the species, although they will not be familiar with its management; The pre-germinative method of mechanical scarification used was efficient. [ABSTRACT FROM AUTHOR]

Peach (Prunus persica) is an economically important crop in the southeastern United States. Prunus necrotic ringspot virus (PNRSV) is a pollen-borne pathogen that affects peaches and other stone fruits worldwide. Wild Prunus spp. in the proximity of peach orchards have the potential to serve as reservoirs of PNRSV. To better understand virus movement at the crop–wild flora interface, we tested peach trees for PNRSV via RT-PCR, sequenced the coat protein genes of PNRSV isolates, and compared them to PNRSV CP sequences from nearby wild black cherry (Prunus serotina) trees. Additionally, we collected bloom time data from P. persica and P. serotina over three seasons to determine if the bloom periods of these species overlap. PNRSV sequence analysis shows the separation between PNRSV isolates from peach, which were highly variable, and wild black cherry, which formed a distinct monophyletic clade with the exception of a single isolate. Bloom time data suggest a temporal separation of flowering periods between the two species, with peach trees going through that phenophase before wild black cherries. Taken together, these results suggest that if movement of PNRSV occurs between peach and wild black cherry at this location, we hypothesize based on our data that it would occur predominantly in one direction: from peach to wild black cherry. [ABSTRACT FROM AUTHOR]

Waterlogging is a major abiotic stress that plants encounter as a result of climate change impacts. Peach is very sensitive to hypoxia during waterlogging, which causes poor tree vigor and huge economic losses. The molecular mechanism underlying the peach response to waterlogging and reoxygenation remains unclear. Here, the physiological and molecular responses of 3-week-old peach seedlings under waterlogged and recovery conditions were comprehensively analyzed. As a result, waterlogging significantly reduced plant height and biomass with inhibition of root growth when compared with control and reoxygenation. Similar results were observed for photosynthetic activities and gaseous exchange parameters. Waterlogging increased lipid peroxidation, hydrogen peroxide, proline, glutamic acid and glutathione contents, while superoxide dismutase, peroxidases and catalase activities were decreased. The glucose and fructose contents were accumulated, contrary to sucrose which was reduced remarkably throughout the stress periods. The level of endogenous indole acetic acid (IAA) was increased in waterlogging but decreased after reoxygenation. However, the change trends of jasmonic acid (JA), cytokinins and abscisic acid (ABA) levels were opposite to IAA. In transcriptomic analysis, there were 13,343 differentially expressed genes (DEGs) with higher and 16,112 genes with lower expression. These DEGs were greatly enriched in carbohydrate metabolism, anaerobic fermentation, glutathione metabolism and IAA hormone biosynthesis under waterlogging, while they were significantly enriched in photosynthesis, reactive oxygen species scavenging, ABA and JA hormones biosynthesis in reoxygenation. Moreover, several genes related to stress response, carbohydrate metabolism and hormones biosynthesis were significantly changed in waterlogging and reoxygenation, which indicated unbalanced amino acid, carbon and fatty acid pools in peach roots. Taken together, these results suggest that glutathione, primary sugars and hormone biosynthesis and signaling might play key roles in plant response to waterlogging. Our work provides a comprehensive understanding of gene regulatory networks and metabolites in waterlogging stress and its recuperation, which will facilitate peach waterlogging control. [ABSTRACT FROM AUTHOR]

In higher plants, light-harvesting chlorophyll a/b binding (Lhc) proteins play a vital role in photosynthetic processes and are widely involved in the regulation of plant growth, development, and response to abiotic stress. However, the Lhc gene family has not been well identified in peaches (Prunus persica L.). In this study, 19 PpLhc genes were identified in the peach genome database, which were unevenly distributed on all chromosomes. Phylogenetic analysis demonstrated that PpLhc proteins could be divided into three major subfamilies, each of whose members had different exon–intron structures but shared similar conserved motifs. A total of 17 different kinds of cis-regulatory elements were identified in the promoter regions of all PpLhc genes, which could be classified into three categories: plant growth and development, stress response, and phytohormone response. In addition, transcriptomic data analysis and RT-qPCR results revealed that the expression profiles of some PpLhc genes changed under drought treatment, suggesting the crucial roles of Lhc genes in the regulation of plant tolerance to drought stress. Taken together, these findings will provide valuable information for future functional studies of PpLhc genes, especially in response to drought stress. [ABSTRACT FROM AUTHOR]

The effect of temperature on the ability of 2-chloroethylphosphonic acid (ethephon, ETH) and the 1-aminocyclopropane carboxylic acid (ACC) to induce ethylene production in fruitlets and abscission of fruitlets and leaves when applied at postbloom (~15 mm fruit diameter) was studied using 5-year-old 'Sweet Lady'/Rootpac-20 peach [Prunus persica (L.) Batsch] trees kept in pots in environment-controlled growth rooms. ETH at 150 mg L−1 and ACC at 500 mg L−1 effectively thinned peaches. Increasing the temperature from 10 to 20 °C pronounced the ETH-induced fruit and leaf abscission and the ACC-induced leaf abscission and decreased stomatal conductance in leaves. However, the ACC thinning effect was not affected by increasing temperature, as well as ETH- and ACC-induced ethylene production in fruitlets and in the quantum yield of PSII photochemistry. Changes in ethylene peak in fruitlets and stomatal conductance in leaves were related to the abscission response. [ABSTRACT FROM AUTHOR]

SUMMARY: Red coloration around the stone (Cs) is an important trait of canned peaches (Prunus persica). In this study, an elongated hypocotyl 5 gene in peach termed PpHY5 was identified to participate in the regulation of the Cs trait. The E3 ubiquitin ligase PpCOP1 was expressed in the flesh around the stone and could interact with PpHY5. Although HY5 is known to be degraded by COP1 in darkness, the PpHY5 gene was activated in the flesh tissue surrounding the stone at the ripening stages and its expression was consistent with anthocyanin accumulation. PpHY5 was able to promote the transcription of PpMYB10.1 through interacting with its partner PpBBX10. Silencing of PpHY5 in the flesh around the stone caused a reduction in anthocyanin pigmentation, while transient overexpression of PpHY5 and PpBBX10 resulted in anthocyanin accumulation in peach fruits. Moreover, transgenic Arabidopsis seedlings overexpressing PpHY5 showed increased anthocyanin accumulation in leaves. Our results improve our understanding of the mechanisms of anthocyanin coloration in plants. Significance Statement: Our results provide insight into the mechanisms underlying anthocyanin accumulation in darkness. [ABSTRACT FROM AUTHOR]

The ATP-binding cassette (ABC) transporter family is a large and diverse protein superfamily that plays various roles in plant growth and development. Although the ABC transporters are known to aid in the transport of a wide range of substrates across biological membranes, their role in anthocyanin transport remains elusive. In this study, we identified a total of 132 putative ABC genes in the peach genome, and they were phylogenetically classified into eight subfamilies. Variations in spatial and temporal gene expression levels resulted in differential expression patterns of PpABC family members in various tissues of peach. PpABCC1 was identified as the most likely candidate gene essential for anthocyanin accumulation in peach. Transient overexpression of PpABCC1 caused a significant increase in anthocyanin accumulation in tobacco leaves and peach fruit, whereas virus-induced gene silencing of PpABCC1 in the blood-fleshed peach resulted in a significant decrease in anthocyanin accumulation. The PpABCC1 promoter contained an MYB binding cis-element, and it could be activated by anthocyanin-activator PpMYB10.1 based on yeast one-hybrid and dual luciferase assays. Thus, it seems that PpABCC1 plays a crucial role in anthocyanin accumulation in peach. Our results provide a new insight into the vacuolar transport of anthocyanins in peach. [ABSTRACT FROM AUTHOR]

Summary: Hemicycliophora species are migratory root ectoparasites of higher plants, commonly known as sheath nematodes. The present study describes a new species, Hemicycliophora geraerti n. sp., recovered from the rhizosphere of peach tree (Prunus persica) in Zhejiang Province, China. This species is characterised by a cuticular sheath loosely fitting to the body, a lip region slightly set-off with body contour bearing 3-4 annuli, oral plate narrow, ovate, and non-protruding, amphidial apertures plugged, dorsoventrally flanked in the first lip annulus, stylet 110 (103-116) μ m long and flexible, excretory pore located 4-7 annuli posterior to the base of the pharyngeal bulb; vulval lips modified with a small vulval sleeve, anus located 16 (13-21) annuli posterior to vulva, tail elongated, having a narrowly rounded slightly offset spike. The molecular characterisation and phylogenetic analyses based on D2-D3 expansion segments of the 28S rRNA, ITS rRNA, and COI mtDNA gene indicated the unique status and support the novelty of this population of Hemicycliophora , therefore herein described as H. geraerti n. sp. [ABSTRACT FROM AUTHOR]

Winter pruning has been a common practice in peach. Twig topping has been associated with it, but this practice has been used at the same intensity, regardless of the cultivar. Therefore, this study aimed at evaluating productive behavior and quality of 'Maciel' peach grafted on 'Capdeboscq' and 'Okinawa' (P. persica) as rootstocks, when they were submitted to different twig topping intensities in winter pruning. The following three pruning intensities were evaluated: short pruning, when 2/3 of the productive twig was removed; long pruning, when 1/3 of the twig was removed; and pruning with no topping, when twigs were kept integral. Effective fructification is lower when 'Maciel' peach trees are submitted to short pruning, but it leads to fruit with higher weight and flesh firmness, besides larger diameters. Pruning with no twig topping and long pruning increased the fruit number and yield per tree. Not only fruit weight, diameter and soluble solid content, but also yield per tree of 'Maciel' peach are affected by 'Capdeboscq' and 'Okinawa', regardless of the intensity of twig topping throughout pruning. Higher concentration of soluble solids was found in peaches grafted in Okinawa. While the highest production was verified with the use of the 'Capdeboscq' rootstock. [ABSTRACT FROM AUTHOR]

This research studied the effect of the inducers acibenzolar-S-Methyl, potassium phosphite, and potassium silicate on the leaf mineral concentration of peach. The experiment was carried out in Tezontepec, Puebla, in the years 2017 and 2018. The treatments consisted of the foliar application of the resistance inducers acibenzolar-S-Methyl, potassium phosphite, and potassium silicate. Inducers were applied at commercially recommended dose. The experimental design was in randomized blocks with four replicates. Foliar quantification of nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, copper and silicon was carried out. The use of resistance inducers increases the leaf concentrations of calcium. The interaction of resistance inducers and years of application modified the foliar concentration of magnesium, phosphorus and sulfur in peaches. [ABSTRACT FROM AUTHOR]

Fruit development period (FDP), defined as the time between full bloom and maturity, varies greatly in peaches (Prunus persica L. Batsch). It is necessary to develop molecular markers associated with maturity date to extend the harvest season in new peach cultivars. We designed the 260 SSR primer set covering the entire genome of approximately 300 kb to 1 Mb based on P. persica cultivar ‘Mihong’ genome sequence. The SSR markers were used to survey the relationship between the parentages ‘Yumeyong’ and ‘Chiyomaru’ and their offspring cultivars ‘Mihong’, ‘Yumi’, ‘Misshong’ and ‘Soomee’. Male cultivar ‘Chiyomaru and its offspring cultivars ‘Mihong’, Yumi’, and ‘Misshong’ are early and middle maturity cultivars with FDP of 77, 76, 82, and 108 days, respectively, whereas female cultivar ‘Yumyeong’ and its offspring cultivar ‘Soomee’ are late maturity cultivars with FDP of 128 days. Three regions of SSR markers could distinguish between early, middle, and late maturity cultivars. In the early stages of breeding, these markers will be used for marker-assisted selection (MAS) in the parentages ‘Yumyeong’ and ‘Chiyomaru’ and their offspring cultivars. [ABSTRACT FROM AUTHOR]

Cold storage is used to extend peach commercial life, but can affect quality. Quality changes are assessed through the content of nutritionally relevant compounds, aroma, physical characters and/or sensorially. Here, six peach and nectarine cultivars were sampled at commercial harvest and after 7 days of 1 °C storage. A trained panel was used to evaluate sensorial characters, while carotenoids, phenolics, vitamin C, total sugars, and qualitative traits including firmness, titrable acidity and soluble solid content were integrated with volatile organic compound (VOC) analysis previously reported. The different analyses reveal interesting patterns of correlation, and the six cultivars responded differently to cold storage. Sensory parameters were correlated with 64 VOCs and seven intrinsic characters. Acidity, firmness, and 10 VOCs were strongly negatively correlated with harmony and sweetness, but positively correlated with bitterness, astringency, and crunchiness. In contrast, Brix, b-carotene, and six VOCs were positively correlated with harmony and sweetness. [ABSTRACT FROM AUTHOR]

This study focuses on the preliminary phytochemical screening, nutritive value, and antimicrobial activity of Prunus persica leaves extracts. Proximate analysis of the P. persica leaves shows the moisture content (10.615%), crude fiber.534%), crude fat (4.443%), total protein (27.468%), total carbohydrate (41.566%), and nutritive value (316.123kcal/100g). The qualitative phytochemical studies show the presence of tannins, saponins, tannins, and flavonoids. The antimicrobial activity of P. persica leaves extracts was performed against three bacteria (Escherichia coli MTCC-40, Pseudomonas aeruginosa MTCC-2474, Staphylococcus aureus-MTCC-1144) and two fungal strains (Penicillium sp. and Aspergillus sp.) The ethyl acetate leaves extract of P. persica showed the highest antibacterial activity and the highest antifungal activity compared to other extracts (ethyl acetate > ethanol> chloroform). Overall, this study suggests that P. persica has good nutritive value, is an excellent source of phytochemicals, and shows good antimicrobial activity. [ABSTRACT FROM AUTHOR]

Peaches contain high amounts of polyphenol compounds. The consumption of peaches gives protection against various conditions such as obesity, diabetes, cardiovascular and bacterial diseases, and inflammation. The present study aimed to examine the phytochemical compounds and the antioxidant, antibacterial, anti-α-glucosidase, and anti-α-amylase activities of the different extracts (methanol, ethanol, and hexane) of fresh red peach collected from the Mersin province in Turkey. In this study, chemical compositions of methanol and ethanol extracts prepared from peach pulp were studied by using liquid chromatography-mass spectrometry (LC-MS/MS). Thirteen metabolites: quinic acid, fumaric acid, aconitic acid, protocatechuic acid, salicylic acid, chlorogenic acid, rutin, isoquercitrin, hesperidin, astragalin, nicotiflorin, quercetin, and amentoflavone, were identified in ethanol extracts and also these phenolic compounds, excluding salicylic acid, were identified in the methanol extract. The ethanol extract showed the most activity in all enzyme inhibition and in antibacterial and antioxidative activity assays, which is mainly due to its rich phenolic content. The most dominant compounds determined in ethanol extract were quinic acid, chlorogenic acid, fumaric acid, and isoquercitrin respectively. According to the results of this study, ethanol extract in particular is a potential ingredient to be used in food-derived antidiabetic and antibacterial formulations. [Display omitted] • The first report about bioactive properties of fresh red peach extracts. • Quinic, chlorogenic and fumaric acid and isoquercitrin were dominant in peach. • Phenolic rich ethanol extract demonstrated strong antidiabetic properties. • Total phenolic and antioxidant values were detected ethanol>methanol>hexane. • Ethanol and methanol extracts exhibited strong antibacterial activities. [ABSTRACT FROM AUTHOR]

The branch construction of trees is based on phytomers, repetitive subunits defined as node + leaf + axillary meristem + internode. The rate at which phytomers are added to a shoot is termed the phyllochron, which is determined by genetics, endogenous regulation and environmental conditions. The phyllochron is fundamental to understanding the growth of plants. Most phyllochron studies on woody species are of young plants under controlled conditions without consideration for different types of shoots that are present in mature trees. In this 2-year field study, we investigated seasonal patterns of phyllochron development on both proleptic and epicormic shoots of mature peach trees (Prunus persica) exposed to two irrigation treatments. One treatment was not irrigated until significant stress was detected via water potential by pressure bombing. In the second treatment trees were normally irrigated with ~5.84 cm of water each week to match evapotranspirational loss. Midday stem water potential readings were regularly collected to assess the level of water stress experienced by the trees. Measurements of individual leaves and their corresponding internodes were taken along tagged proleptic and epicormic shoots three times per week from the beginning to the end of two growing seasons. Leaf measurements were used to calculate the phyllochron. The phyllochron increased as the season progressed. This increase could not be explained by traditionally accepted effects of temperature or light. The more vigorous epicormic shoots added leaves significantly faster than proleptic shoots on trees in both water deficit and normally irrigated treatments. Additionally, epicormic shoots produced leaves with significantly greater leaf length and leaf area. Midday stem water potentials were more negative in trees in the water deficit treatments only after proleptic shoots stopped growing. The phyllochron did increase while leaf length and leaf area decreased on epicormic shoots of deficit irrigated trees in the 2010 growing season. The phyllochron of both shoot types gradually increased over the season, which was primarily due to an endogenous rank or shoot ageing effect. Differences between shoot types indicate that the phyllochron is variable among shoots on the same tree and is associated with shoot vigour. Water deficit increased the phyllochron and over all shoot growth rate.

Wild peach is an important resource for improving existing peach varieties. However, the extant populations of wild peach show fragmented distribution due to human disturbance and geographic isolation. In this study, we used natural populations (or wild populations) of Prunus persica (Rosaceae) to assess the genetic effects of habitat fragmentation. A total of 368 individuals sampled from 16 natural populations were analyzed using 23 polymorphic simple sequence repeat (SSR) markers. Prunus persica maintained low within-population genetic variation and high level of genetic differentiation. Two genetic clusters were revealed based on three different methods (UPGMA, PCoA, and STRUCTURE). All populations showed a significant heterozygosity deficiency and most extant populations experienced recent reduction in population size. A significant isolation by distance (IBD) was observed with Mantel's test. Compared to historical gene flow, contemporary gene flow was restricted among the studied populations, suggesting a decrease in gene flow due to habitat fragmentation. Habitat fragmentation has impacted population genetic variation and genetic structure of P. persica. For breeding and conservation purpose, collecting as many individuals as possible from multiple populations to maximize genetic diversity was recommended during the process of germplasm collection. In addition, populations from central China had higher genetic diversity, suggesting these populations should be given priority for conservation and germplasm collection. [ABSTRACT FROM AUTHOR]

The demand for skin-whitening agents is high across the world, including Asian countries. An extensive screening using a tyrosinase inhibition assay was performed in order to discover novel plant materials. In our research program investigating a safe and effective agent, 50% ethanolic extracts prepared from discarded parts of Prunus persica were screened for in vitro tyrosinase inhibitory activity. Among the extracts tested, twig extract showed the most potent inhibitory activity: 38% inhibition at 500 µg/mL. The investigation of active compounds in twig extract found four flavanones that acted as moderate inhibitors, including (−)-prunin, persiconin, (+)-dihydrokaempferol, and (−)-naringenin. These compounds were only observed in the twig extract following preliminary quantification by HPLC, with the following concentrations: (−)-prunin, 1.8 mg/g sample; persiconin, 0.8 mg/g sample; (+)-dihydrokaempferol, 0.8 mg/g sample; (−)-naringenin, 1.7 mg/g sample. These results suggest that twig extracts can be more useful for skin-whitening compared with other parts of the plant. In addition, a new constituent of twig extract was identified, namely isoquercitrin, which suggests that twig extract can be a potent source of flavones and flavanones. Further studies on the identification of novel compounds from twig extract are now underway in our laboratory. [ABSTRACT FROM AUTHOR]

The seasonal variations of the phenolic content in the stem bark of Prunus persica var. nucipersica were analyzed by using high pressure liquid chromatography/electrospray ionization mass spectrometry. Great differences were observed for flavanone 5‐O‐glycosides, rutin and acetylated p‐coumaroylsucrose conjugates containing 0–4 acetyl groups. It is a matter of discussion in which period of the year, May‐August or September‐April, the bark of Prunus persica is the most valuable source of bioactive constituent. If the presence of rutin is desirable, May‐August is the appropriate harvest period, whereas September‐April is appropriate if the presence of flavanone 5‐O‐glycosides is of interest. [ABSTRACT FROM AUTHOR]

Summary: The fruit surface has an enormous impact on the external appearance and postharvest shelf‐life of fruit. Here, we report two functionally redundant genes, PpMYB25 and PpMYB26, involved in regulation of fruit skin texture in peach.PpMYB25 can activate transcription of PpMYB26 and they both induce trichome development and cuticular wax accumulation, resulting in peach fruit with a fuzzy and dull appearance. By contrast, nonfunctional mutation of PpMYB25 caused by an insertional retrotransposon in the last exon in nectarine fails to activate transcription of PpMYB26, resulting in nectarine fruit with a smooth and shiny appearance due to loss of trichome initiation and decreased cuticular wax accumulation.Secondary cell wall biosynthesis in peach fruit pubescence is controlled by a transcriptional regulatory network, including the master regulator PpNAC43 and its downstream MYB transcription factors such as PpMYB42, PpMYB46 and PpMYB83.Our results show that PpMYB25 and PpMYB26 coordinately regulate fruit pubescence and cuticular wax accumulation and their simultaneous perturbation results in the origin of nectarine, which is botanically classified as a subspecies of peach. [ABSTRACT FROM AUTHOR]

Two trials were conducted under Mediterranean conditions to monitor several physiological indicators before harvest (leaf chlorophyll concentration, quantum yield of photosystem II electron transport, stem water potential, and stomatal conductance) and some agronomic performance parameters before and at harvest (vigor, fruit growth, fruit size, fruit weight, and yield), of 'Vairo' almond and 'Big Top' nectarine cultivars grafted onto eight Prunus rootstocks, six of which are common in both cultivars. For both 'Vairo' almond and 'Big Top' nectarine cultivars, factors including rootstock, date, and the interaction between rootstock and date, from fruit set to harvest were evaluated. Significantly affected were certain physiological and agronomical traits which were evaluated before harvest, with stem water potential being the parameter affected by interaction in both cultivars. In fact, the stem water potential presented low levels in Rootpac-20 and high levels in Rootpac-40 for both cultivars. With regard to the other physiological traits evaluated during the growing period, changes in stomatal conductance were observed in 'Vairo', but not in 'Big Top'. Comparing rootstocks throughout the season, Rootpac-40 and IRTA-1 exhibited the highest stomatal conductance values, whereas the lowest was observed in Rootpac-R; Rootpac-20 and Ishtara also presented low values. Regarding agronomical traits at harvest, GF-677 and IRTA-1 produced high yields for 'Vairo' almond cultivar, whereas Rootpac-40 and Ishtara performed better with 'Big Top' nectarine cultivar. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate the cold shock, before cold storage, influence on quality of cold stored 'Douradão' peaches, with the objective to reduce the chilling injuries. For this, the fruits were exposed at -2 or -4 °C for 1, 2, or 3 hours. After treatments the fruits were stored at 0.5 ± 1 °C and 85-90% RH for 30 days. The variables evaluated suggests that the treatment with cold shock does not influence the physical and chemical fruit characteristics but intensifies and accelerates the onset of symptoms characteristic of chilling injuries. This may be associated with changes in enzymes of endo-PG, PME, PL and β-Gal amount and activity that affect the dynamics of cell wall degradation, in the case of woolliness and changes in enzymes PAL, POD and PPO activity and the increased membrane permeability in the case of internal browning. The anticipation of the chilling injuries and decay in fruits subjected to cold shock suggests that this practice should not be used in order to maintain the fruit quality. [ABSTRACT FROM AUTHOR]

The TIFY family is a plant-specific gene family involved in regulating many plant processes, such as development and growth, defense and stress responses, fertility and reproduction, and the biosynthesis of secondary metabolites. The v2.0 peach (Prunus persica) genome, which has an improved chromosome-scale assembly and contiguity, has recently been released, but a genome-wide investigation of the peach TIFY family is lacking. In this study, 16 TIFY family genes from the peach genome were identified according to the peach reference genome sequence information and further validated by cloning sequencing. The synteny, phylogenetics, location, structure, and conserved domains and motifs of these genes were analyzed, and finally, the peach TIFY family was characterized into 9 JAZ , 1 TIFY , 1 PPD and 5 ZML subfamily members. Expression profiles of peach JAZ , PPD , and ZML genes in various organs and fruit developmental stages were analyzed, and they showed limited effects with fruit ripening cues. Four TIFY members were significantly affected at the mRNA level by exogenous treatment with MeJA in the peach epicarp, and among them, PpJAZ1 , PpJAZ4 and PpJAZ5 were significantly correlated with fruit epicarp pigmentation. In addition, the TIFY family member protein interaction networks established by the yeast two-hybrid (Y2H) assay not only showed similar JAZ-MYC2 and JAZ homo- and heterodimer patterns as those found in Arabidopsis but also extended the JAZ dimer network to ZML-ZML and JAZ-ZML interactions. The PpJAZ3-PpZML4 interaction found in this study suggests the potential formation of the ZML-JAZ-MYC complex in the JA-signaling pathway, which may extend our knowledge of this gene family's functions in diverse biological processes. [ABSTRACT FROM AUTHOR]