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In common nutrient management in peach orchards in China, a large amount of nitrogen fertilizer is used. However, low nitrogen absorption and utilization rate results in nitrogen loss and greenhouse gas emissions, which is not favorable for cleaner production in peach orchards. In this experiment, nitrogen leaching, ammonia volatilization, greenhouse gas emissions under bag-controlled release fertilizer (BCRF) were evaluated. In addition, the impact of BCRF on soil nutrient status in peach orchards, peach root system growth, nitrogen absorption and utilization rate, fruit quality, and the potential for using BCRF in major peach-producing areas in China to reduce the amount of nitrogen fertilizer application were also investigated. Results showed that BCRF maintained a stable supply of nutrients to soil, decreased nitrogen leaching, ammonia volatilization and greenhouse gas emissions while nitrogen loss was significantly reduced from peach orchard soil. Also, BCRF reduced the combined global warming potential at 20-, 100-, and 500-years. A 5-year study revealed that application of BCRF promoted the formation of a dense root system in peach trees by the development of fine roots and a more concentrated root distribution. This extended the lifespan of the root system and improved fruit quality. 15N tracer experiments showed that BCRF significantly increased the absorption and utilization rate of nitrogen by peach trees. BCRF reduced the amount of nitrogen fertilizers applied by 65–82% compared to common fertilizer application methods without decreasing peach yield, so it has huge potential for reducing the amount of nitrogen fertilizer used as well as fertilizer input costs in peach production. The results showed that BCRF has huge application potential as a new, environmentally friendly, low-cost, and efficient fertilizer for cleaner production in peach orchards. Image 1048 • Bag-controlled release fertilizer can maintain stable supply of nutrients to soil. • HighlightsHighlightBag-controlled release fertilizer decreases nitrogen leaching, ammonia volatilization from peach orchard soil. • Bag-controlled release fertilizer would reduce greenhouse gas emissions and the combined global warming potential. • Bag-controlled release fertilizer promotes the formation of a dense root system of peach trees. • Bag-controlled release fertilizer has a huge potential for reducing the nitrogen applied amount in peach production. [ABSTRACT FROM AUTHOR]

Trehalose-6-phosphate synthase (TPS) is essential for plant growth and development, linking trehalose-6-phosphate (T6P) to carbon metabolism. However, little is known about the TPS gene family in peaches and their potential roles in regulating carbohydrates in peach fruit. In this study, nine TPS genes were identified in the peach genome and named according to the homologous genes in Arabidopsis. Phylogenetic analysis showed that three subfamilies were identified, including TPSI, TPSII-1, and TPSII-2, which were also consistent with gene structure analysis. Considerable cis-elements were enriched in the promoters, including plant hormone-related elements. Tissue-specific analysis showed that these TPS genes were mainly expressed in leaves, stems, and fruit, showing different expression patterns for each gene. In addition, during fruit development, the content of trehalose-6-phosphate (T6P) was positively correlated with the expression of PpTPS7a and negatively with sucrose non-fermenting-1-related kinase 1 (SnRK1) activity. Transient overexpression and silencing of PpTPS7a in peach fruit validated its function in regulating T6P content and SnRK1 activity. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Waterlogging resistance and evaluation of physiological mechanism of three peach (Prunus persica) rootstocks" published in the journal Protoplasma. The correction addresses the incorrect numbering of Figures 5, 6, and 7 in the published proof. The corrected figures depict the effects of waterlogging on cell death and ROS accumulation in the leaves of peach rootstocks and grafted seedlings. The original article has been corrected. The publisher, Springer Nature, remains neutral regarding jurisdictional claims and institutional affiliations. [Extracted from the article]

Plants suffer from a variety of environmental stresses during their growth and development. The evolutionarily conserved sucrose nonfermenting kinase 1-related protein kinase 1 (SnRK1) plays a central role in the regulation of energy homeostasis in response to stresses. In plant cells, autophagy is a degradation process occurring during development or under stress, such as nutrient starvation. In recent years, SnRK1 signaling has been reported to be an upstream activator of autophagy. However, these studies all focused on the regulatory effect of SnRK1 on TOR signaling and the autophagy-related gene 1 (ATG1) complex. In this study, overexpression of the gene encoding the Prunus persica SnRK1 α subunit (PpSnRK1α) in tomato improved the photosynthetic rates and enhanced the resistance to low nutrient stress (LNS). Overexpression of PpSnRK1α increased autophagy activity and upregulated the expression of seven autophagy-related genes (ATGs). The transcriptional levels of SlSnRK2 family genes were altered significantly by PpSnRK1α, signifying that PpSnRK1α may be involved in the ABA signaling pathway. Further analysis showed that PpSnRK1α not only activated autophagy by inhibiting target of rapamycin (TOR) signaling but also enhanced ABA-induced autophagy. This indicates that PpSnRK1α regulates the photosynthetic rate and induces autophagy, and then responds to low nutrient stress. [ABSTRACT FROM AUTHOR]

Resistance genes (R genes) are a class of genes that are immune to a wide range of diseases and pests. In planta, NLR genes are essential components of the innate immune system. Currently, genes belonging to NLR family have been found in a number of plant species, but little is known in peach. Here, 286 NLR genes were identified on peach genome by using their homologous genes in Arabidopsis thaliana as queries. These 286 NLR genes contained at least one NBS domain and LRR domain. Phylogenetic and N-terminal domain analysis showed that these NLRs could be separated into four subfamilies (I-IV) and their promoters contained many cis-elements in response to defense and phytohormones. In addition, transcriptome analysis showed that 22 NLR genes were up-regulated after infected by Green Peach Aphid (GPA), and showed different expression patterns. This study clarified the NLR gene family and their potential functions in aphid resistance process. The candidate NLR genes might be useful in illustrating the mechanism of aphid resistance in peach. [ABSTRACT FROM AUTHOR]

Waterlogging occurs due to poor soil drainage or excessive rainfall. It is a serious abiotic stress factor that negatively affects crop growth. Waterlogging often causes plants to shed leaves, fruits, and, ultimately, to die. Peach (Prunus persica) trees are generally intolerant to waterlogging, and the primary peach rootstock used in Chinais "Maotao," which has very poor resistance to sensitivity. Therefore, waterlogging has become a restriction on the development of the peach industry in many regions. In this experiment, we tested the waterlogging resistance of "Maotao (Prunus persica (L.) Batsch)" (MT), "Shannong1 (GF677 × Cadaman)" (SN1), and "Mirabolano 29C (Prunus cerasifera)" (M29C) rootstocks. Using a simulated waterlogging method, the effects of waterlogging on the photosynthetic system, leaf pigments, osmotic adjustment, lipid membrane peroxidation, and antioxidant system of these three peach rootstocks were studied, and the changes of chlorophyll fluorescence parameters and fluorescence imaging were observed. The results showed that, with prolonged waterlogging, the photosynthetic pigment content and photosynthesis of the three peach rootstocks decreased rapidly, but the decomposition rate of SN1 and M29C chlorophyll was slower, and it still had high light energy absorption and energy transfer capabilities under waterlogging stress, which reduced the damage caused by waterlogging stress; under the stress of flooding, the osmoregulatory substances of the three rootstocks increased to varying degrees compared with normal conditions. At the same time, the enzyme activity of superoxide dismutase (SOD) activity, peroxidase (POD) activity, and catalase (CAT) activity in the leaves of the three rootstocks under flooding stress all increased and then decreased; during this period, malondialdehyde (MDA) continued to increase, and SN1 and M29C were significantly lower than MT; and chlorophyll fluorescence parameters, including the maximum photochemical efficiency (Fv/Fm), actual photochemical efficiency (ΦPSII), photochemical quenching coefficient (qP), non-photochemical quenching (NPQ), and electron transfer rate (ETR) decreased significantly. The tolerance of SN1 and M29C to waterlogging was significantly better than that of MT rootstocks. The rootstock and grafted seedlings of SN1 have good waterlogging tolerance. [ABSTRACT FROM AUTHOR]

Key message: We confirmed the roles of auxin, CK, and strigolactones in apical dominance in peach and established a model of plant hormonal control of apical dominance in peach.Abstract: Auxin, cytokinin, and strigolactone play important roles in apical dominance. In this study, we analyzed the effect of auxin and strigolactone on the expression of ATP/ADP isopentenyltransferase (IPT) genes (key cytokinin biosynthesis genes) and the regulation of apical dominance in peach. After decapitation, the expression levels of PpIPT1, PpIPT3, and PpIPT5a in nodal stems sharply increased. This observation is consistent with the changes in tZ-type and iP-type cytokinin levels in nodal stems and axillary buds observed after treatment; these changes are required to promote the outgrowth of axillary buds in peach. These results suggest that ATP/ADP PpIPT genes in nodal stems are key genes for cytokinin biosynthesis, as they promote the outgrowth of axillary buds. We also found that auxin and strigolactone inhibited the outgrowth of axillary buds. After decapitation, IAA treatment inhibited the expression of ATP/ADP PpIPTs in nodal stems to impede the increase in cytokinin levels. By contrast, after GR24 (GR24 strigolactone) treatment, the expression of ATP/ADP IPT genes and cytokinin levels still increased markedly, but the rate of increase in gene expression was markedly lower than that observed after decapitation in the absence of IAA (indole-3-acetic acid) treatment. In addition, GR24 inhibited basipetal auxin transport at the nodes (by limiting the expression of PpPIN1a in nodal stems), thereby inhibiting ATP/ADP PpIPT expression in nodal stems. Therefore, strigolactone inhibits the outgrowth of axillary buds in peach only when terminal buds are present. [ABSTRACT FROM AUTHOR]

A reasonable main branch opening angle can improve the canopy light environment of a tree, change the direction of nutrient transport, and promote the formation of flower buds. In this experiment, 3-year-old 'Lu Hong 618' was used as the test material to study the effects of different main branch opening angles (three treatments: 45°, 65°, and 85°) on the canopy light distribution, canopy characteristics, fruit quality, and flower bud quality of 'Y'-shaped peach trees. The main findings were as follows: the solar energy utilization in the canopy varied greatly between different main branch opening angles, with the best relative light intensity of the canopy at 85°. In addition, the canopy light distribution on photosynthesis was more reasonable at 85°, and the daily variation range of CO2 concentration in the inner canopy was the greatest, which facilitated ventilation and light penetration in the inner canopy. With the increase in the main branch opening angle, the new growth of peach trees and the growth of the main branch trunk were inhibited. A reasonable branch opening angle results in good branch structure and leaf morphology. Leaf stomatal morphology and the soluble sugar and starch contents at different levels of the canopy are influenced by canopy light, and higher levels of canopy light can significantly increase the stomatal size and improve the leaf photosynthetic capacity, SPAD value, and soluble sugar and starch contents. With the increase in the main branch opening angle, C/N tended to increase. In addition, the distribution pattern of fruit quality in the canopy was similar to that of light distribution. In the same fruiting part, the fruit quality was higher at 85° and 45° than at 65° and slightly higher at 85° than at 45°, but the difference was not significant. The effects of different main branch opening angle treatments on the fruit weight, flesh firmness, soluble solids, and titratable acid were more significant. The 85° pulling angle effectively increased the light intensity of the different canopy layers of the peach trees and promoted the accumulation of nutrients. An 85° pulling angle can be used as a more suitable pulling angle for peach tree shaping cultivation. [ABSTRACT FROM AUTHOR]

Background: HD-Zips (Homeodomain-Leucine Zippers) are a class of plant-specific transcription factors that play multiple roles in plant growth and development. Although some functions of HD-Zip transcription factor have been reported in several plants, it has not been comprehensively studied in peach, especially during adventitious root formation of peach cuttings. Results: In this study, 23 HD-Zip genes distributed on 6 chromosomes were identified from the peach (Prunus persica) genome, and named PpHDZ01-23 according to their positions on the chromosomes. These 23 PpHDZ transcription factors all contained a homeomorphism box domain and a leucine zipper domain, were divided into 4 subfamilies(I-IV) according to the evolutionary analysis, and their promoters contained many different cis-acting elements. Spatio-temporal expression pattern showed that these genes were expressed in many tissues with different levels, and they had distinct expression pattern during adventitious root formation and development. Conclusion: Our results showed the roles of PpHDZs on root formation, which is helpful to better understand the classification and function of peach HD-Zip genes. [ABSTRACT FROM AUTHOR]

Nitrogen is an important nutrient element that limits plant growth and yield formation, but excessive nitrogen has negative effects on plants and the environment. It is important to reveal the molecular mechanism of high NUE (nitrogen use efficiency) for breeding peach rootstock and variety with high NUE. In this study, two peach rootstocks, Shannong–1 (S) and Maotao (M), with different NUE were used as materials and treated with 0.1 mM KNO3 for transcriptome sequencing together with the control group. From the results of comparison between groups, we found that the two rootstocks had different responses to KNO3, and 2151 (KCL_S vs. KCL_M), 327 (KNO3_S vs. KCL_S), 2200 (KNO3_S vs. KNO3_M) and 146 (KNO3_M vs. KCL_M) differentially expressed genes (DEGs) were identified, respectively, which included multiple transcription factor families. These DEGs were enriched in many biological processes and signal transduction pathways, including nitrogen metabolism and plant hormone signal transduction. The function of PpNRT2.1, which showed up-regulated expression under KNO3 treatment, was verified by heterologous expression in Arabidopsis. The plant height, SPAD (soil and plant analyzer development) of leaf and primary root length of the transgenic plants were increased compared with those of WT, indicating the roles of PpNRT2.1 in nitrogen metabolism. The study uncovered for the first time the different molecular regulatory pathways involved in nitrogen metabolism between two peach rootstocks and provided gene reserve for studying the molecular mechanism of nitrogen metabolism and theoretical basis for screening peach rootstock or variety with high NUE. [ABSTRACT FROM AUTHOR]

Background: Drought is one of the main concerns worldwide and restricts the development of agriculture. Silicon improves the drought resistance of plants, but the underlying mechanism remains unclear. Results: We sequenced the transcriptomes of both control and silicon-treated peach seedlings under drought stress to identify genes or gene networks that could be managed to increase the drought tolerance of peach seedlings. Peach (Prunus persica) seedlings were used to analyse the effects of silicon on plant growth and physiological indexes related to drought resistance under drought stress. The results showed that silicon addition improved the water use efficiency, antioxidant capacity, and net photosynthetic rate, inhibition of stomatal closure, promoted the development of roots, and further regulated the synthesis of hormones, amino acids and sugars in peach seedlings. A comparative transcriptome analysis identified a total of 2275 genes that respond to silicon under drought stress. These genes were mainly involved in ion transport, hormone and signal transduction, biosynthetic and metabolic processes, stress and defence responses and other processes. We analysed the effects of silicon on the modulation of stress-related hormonal crosstalk and amino acid and sugar metabolism. The results showed that silicon promotes zeatin, gibberellin, and auxin biosynthesis, inhibits the synthesis of abscisic acid, then promote lateral root development and inhibit stomatal closure, and regulates the signal transduction of auxin, cytokinin, gibberellin and salicylic acid. Silicon also regulates the metabolism of various amino acids and promotes the accumulation of sucrose and glucose to improve drought resistance of peach seedlings. Conclusions: Silicon enhanced the drought resistance of peach seedlings by regulating stress-related hormone synthesis and signal transduction, and regulating amino acid and sugar metabolism. [ABSTRACT FROM AUTHOR]

Sucrose nonfermentation 1 (SNF1) related kinase 1 (SnRK1) is a central energy sensor kinase in plants and a key switch regulating carbon and nitrogen metabolism. Fruit quality depends on leaf photosynthetic efficiency and carbohydrate accumulation, but the role of peach (Prunus persica) SnRK1 α subunit (PpSnRK1α) in regulating leaf carbon metabolism and the light signal response remains unclear. We studied the carbon metabolism of tomato leaves overexpressing PpSnRK1α and the responses of PpSnRK1α‐overexpressing tomato leaves to light signals. Transcriptome, metabolome, and real‐time quantitative polymerase chain reaction analyses revealed that uridine 5′‐diphosphoglucose, glutamate, and glucose‐6‐phosphate accumulated in tomato leaves overexpressing PpSnRK1α. The expression of genes (e.g., GDH2, SuSy) encoding enzymes related to carbon metabolism (e.g., glutamate dehydrogenase (GDH2; EC: 1.4.1.3), sucrose synthase (SS; EC: 2.4.1.13)) and chlorophyllase (CLH) encoding chlorophyllase (EC: 3.1.1.14), which regulates photosynthetic pigments and photosynthesis, was significantly increased in PpSnRK1α‐overexpressing plants. PpSnRK1α overexpression inhibited the growth of hypocotyls and primary roots in response to light. The chlorophyll content of the leaves was increased, the activity of SS and ADPG pyrophosphatase (AGPase; EC: 2.7.7.27) was increased, and photosynthesis was promoted in PpSnRK1α‐overexpressing plants relative to wild‐type plants. Under light stress, the net photosynthetic rate of plants was significantly higher in plants overexpressing PpSnRK1α than in wild‐type plants. This indicates that PpSnRK1α promotes the accumulation of carbohydrates by regulating genes related to carbon metabolism, regulating genes related to chlorophyll synthesis, and then responding to light signals to increase the net photosynthetic rate of leaves. [ABSTRACT FROM AUTHOR]

Fruit quality depends largely on the type and amount of sugar accumulated in the fruit. In peach [ Prunus persica (L.) Batsch], sorbitol is the main photosynthetic product and plays a crucial role in sugar metabolism. As a conserved energy sensor, SNF1-related kinase 1 (SnRK1) is involved in the regulation of carbon metabolism. In this study, SnRK1 was able to respond to induction by treatment with exogenous trehalose and sorbitol on 'Ruipan 17' peach fruit. After treatment with 100-mM trehalose for 3 h, the SnRK1 activity decreased by 18% and the activities of sorbitol dehydrogenase (SDH) and sucrose synthase (SS) also decreased significantly, but sucrose phosphate synthase (SPS) activity increased significantly; whereas sorbitol treatment under the same conditions resulted in a 12.6% increase in SnRK1 activity and the activities of SDH and SS synthase also increased significantly, compared with the control. The contents of glucose, fructose and sucrose in peach fruit increased significantly after 3 h of sorbitol treatment. In addition, the interactions between PpSnRK1α and enzymes PpSDH and PpSPS were confirmed by yeast two-hybrid method and the phosphorylation of PpSnRK1α and PpSDH was detected in vitro. Taken together, these results suggest that SnRK1 promotes sorbitol metabolism by activating SDH and it also regulates the activities of SS and SPS that enhance sucrose accumulation in peach fruit. SnRK1 protein kinase is involved in sugar metabolism and has the potential to be used for improving fruit quality. [ABSTRACT FROM AUTHOR]

The nonreducing disaccharide trehalose is widespread in nature. It plays a very important role in plant growth and development. In plants, trehalose is present in trace amounts. High concentration of trehalose disrupts energy balance and inhibits normal growth and development. Studies have shown that high levels of trehalose and trehalose-6-phosphate (T6P), the metabolic precursor of trehalose, inhibit sucrose non-fermenting-1-related protein kinase1 (SnRK1) activity, which affect plant growth and development. However, the role of SnRK1, the energy balance center, in the regulation of trehalose metabolism in plants is unknown. In this study, exogenous trehalose at higher concentrations inhibited the expression of SnRK1 genes, especially PpSnRK1α in peach (Prunus persica) seedlings. This change in gene expression was dependent on trehalose concentration. Furthermore, overexpression of peach PpSnRK1α in Arabidopsis thaliana significantly promoted trehalase activity, reduced T6P content, and suppressed the trehalose synthesis related genes (TPSs , TPPB) expression, promoted the trehalose metabolism of gene expression (TRE1), in addition the transgenic plants alleviated photosynthetic product distribution imbalance (aboveground and underground parts), and enhanced root growth. Yeast two-hybrid and bimolecular fluorescence assays revealed the interaction between PpSnRK1α and peach basic domain leucine zipper transcription factor 11 (PpbZIP11), a key transcription factor of trehalose metabolism, in the nucleus. To summarize, PpSnRK1α overexpression improved bZIP11 transcriptional activity and regulated trehalose metabolism to protect the plants against trehalose-induced damage. This study preliminarily explained the mechanism of SnRK1 regulating trehalose metabolism balance in plants, which laid a foundation for further understanding of energy metabolism and function of SnRK1 in plants. • PpSnRK1α reduces trehalose sensitivity of plants. • Peach PpSnRK1α Interacts with bZIP11 and Maintains Trehalose Balance in Plants. • Overexpression of PpSnRK1α can regulate the distribution of photosynthate in plants and promote root growth. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H 2 S) has been shown to regulate many physiological processes of plants. In this study, we observed that 0.2 mM sodium hydrosulfide (NaHS), a donor of H 2 S, can regulate the root architecture of peach seedlings, increasing the number of lateral roots by 40.63%. To investigate the specific mechanisms by which H 2 S regulates root growth in peach, we used RNA sequencing and heterologous expression technology. Our results showed that exogenous H 2 S led to a 44.50% increase in the concentration of endogenous auxin. Analyses of differentially expressed genes (DEGs) revealed that 963 and 1113 genes responded to H 2 S on days one and five of treatment, respectively. Among the DEGs, 26 genes were involved in auxin biosynthesis, transport, and signal transduction. Using weighted correlation network analysis, we found that the auxin-related genes in the H 2 S-specific gene module were disproportionately involved in polar transport, which may play an important role in H 2 S-induced root growth. In addition, we observed that the expression of LATERAL ORGAN BOUNDARIES DOMAIN 16 (PpLBD16) was significantly up-regulated by exogenous application of H 2 S in peach. Overexpression of PpLBD16 in an Arabidopsis system yielded a 66.83% increase in the number of lateral roots. Under exposure to exogenous H 2 S, there was also increased expression of genes related to cell proliferation, indicating that H 2 S regulates the growth of peach roots. Our work represents the first comprehensive transcriptomic analysis of the effects of exogenous application of H 2 S on the roots of peach, and provides new insights into the mechanisms underlying H 2 S-induced root growth. • Exogenous hydrogen sulfide (H 2 S) can regulate root growth. • The mechanism of H 2 S is regulation of auxin pathways. • LBD, MYB, AP2/ERF transcription factors (TFs) respond to exogenous H 2 S. • Exogenous H 2 S affects genes controlling cell division in roots. • The TF, PpLBD16 , is involved in lateral root formation. [ABSTRACT FROM AUTHOR]

• Confirmed the alleviation of exogenous phosphatidylcholine on peach tree under drought stress. • Prove that exogenous phosphatidylcholine reduces root cell damage under drought stress. • Prove the positive effect of phosphatidylcholine on signal transduction under abiotic stress. • The first one used exogenous phosphatidylcholine to study on deciduous fruit trees. Phosphatidylcholine is a primary class of membrane lipids in most eukaryotes. In plants, the primary phosphatidylcholine biosynthetic pathway and its role in plant growth and development remain elusive due to lack of a mutant model with substantially decreased phosphatidylcholine content. In this study, we investigated whether the exogenous application of phosphatidylcholine can improve drought tolerance and reduce drought-induced damage to one-year-old peach (Prunus persica (L.) Batsch.). In this experiment, phosphatidylcholine was applied directly to the soil at concentrations of 200 mg/L, 500 mg/L, and 1000 mg/L to drought-stressed peach trees and at a concentration of 500 mg/L to control trees not subjected to drought stress. After these treatments, we assessed the net photosynthetic rate and chlorophyll content (i.e. SPAD values) of drought-stressed and unstressed trees. We found that trees sprayed with phosphatidylcholine resembled well-watered trees, but drought-stressed trees not supplemented with phosphatidylcholine showed a lower photosynthetic rate. In trees given sufficient water, the length and width of leaf stomata did not significantly differ regardless of whether plants were treated with phosphatidylcholine or not. However, untreated drought-stressed trees showed incompletely filled guard cells and low stomatal density relative to control trees. In addition, we also found that in drought-stressed trees exogenous phosphatidylcholine treatment resulted in significant increases in proline content as well as decreases in electrolyte leakage and the degree of damage to the cell membrane. Moreover, transmission electron microscopic observation of root cells of treated and untreated peach seedlings showed that phosphatidylcholine treatment protected the integrity of root cells in response to drought stress. Taken together, our results suggest that phosphatidylcholine treatment can improve the drought tolerance of young peach trees and can reduce the damage to cell membranes caused by drought stress. [ABSTRACT FROM AUTHOR]

• Glycine:urea (7:3) treatments significantly promoted root development. • Glycine:urea (7:3) treatments significantly promoted the absorption of NO 3 −. • Denitrification activity was lower at Glycine:urea (7:3) treatments. • Glu and Asp are the main forms of nitrogen transport in peach trees. The mechanism of how glycine combined with urea affects the development of peach trees through nitrogen absorption and metabolism is still unclear. In this study, we investigated the transformation of nitrogen in soil, the nitrogen absorption in roots, and the transformation and transportation of nitrogen in the peach tree at different treatment (no nitrogen fertilizer (CK), urea (T1), glycine (T2), glycine:urea (1:1) (T3), glycine:urea (3:7) (T4), and glycine:urea (7:3) (T5)). Compared with CK, the total dry weight of T5 and T2 was significantly increased by 22.95% and 19.09%, while it was lower at T3. The root activity of T5 was significantly higher than CK by 169.27%. The residual NH 4 + in the soil was consistent with the application ratio of urea, while the conversion of NO 3 − was promoted at T5. Under T5, soil amo A and nif H abundance was higher, while the nir K abundance was higher under T1 and T3. In addition, urease activity was higher at T1, while phosphatase, catalase, and dehydrogenase activities were higher at T5. The NO 3 − content in the root was higher at T5. In roots, the activities of GDH, GOGAT and GS were significantly increased at T5 and T2, while the NR activities of T5 and T1 were significantly increased by 34.60% and 33.64% compared with CK. The aspartic acid and glutamic acid were the main forms of nitrogen transport in wild peaches. PLS-PM analysis showed that nitrogen use efficiency had a very significant direct positive effect on the biomass of peach trees. [ABSTRACT FROM AUTHOR]

Silicon (Si) is abundant in nature, and it has been proved to be beneficial for the healthy growth and development of many plant species, improve plant stress resistance. Gummosis in peach is an invasive disease that causes widespread and serious damage. Mechanical damage and ethylene (ETH) can induce gummosis in peach shoots in the field. In this research, we found that Si as a chemical substance or signal to enhance plant resistance can reduce the synthesis of ETH, thereby inhibiting gummosis in peach. The results showed that Si can decrease the rate of gummosis, reduce the expression level of PpACS1 (1-aminocyclopropane −1-carboxylate synthase gene) and reduce the enzyme activity of polygalacturonase (PG). It was further discovered that Si can regulate the gene expression of PpERF21 and PpERF27. Yeast one-hybrid and dual-luciferase reporter assays showed that PpERF21 and PpERF27, through direct interaction with the promoter of PpPG1 , inhibited the transcriptional activation of PpPG1. Overexpression of PpERF21 and PpERF27 effectively reduced fruit colloid production when bacterial cells harbouring the expression vector were used to instantaneously infect peach fruit. These results show that Si can inhibit the synthesis of ETH and mediate PpERF21 and PpERF27 expression to inhibit the expression of PpPG1 , thereby inhibiting gummosis in peach. • Silicon inhibits peach gummosis by inhibiting ethylene synthesis. • Silicon-mediated ERF genes regulates PpPG expression and inhibits cell wall degradation. • Silicon accumulation in peach trees improves disease resistance. [ABSTRACT FROM AUTHOR]

Salt stress is a major adverse abiotic factor seriously affecting fruit tree growth and development. It ultimately lowers fruit quality and reduces yield. Phosphatidylcholine (PC) is an important cell membrane component that is critical for cell structure and membrane stability maintenance. In this study, we found that the addition of external PC sources significantly increased the tolerance of one-year-old peach trees, Prunus persica (L.) Batsch., to salt stress and attenuated their damage. The effect of exogenous application of 200 mg/L PC exerted the most significant positive effect. Its use caused seedling leaf stomatal opening, contributing to normal gas exchange. Moreover, beneficial effects were exerted also to the root system, which grew normally under salt stress. Meanwhile, phospholipase D activity in the cell was promoted. The production of phosphatidic acid (PA) was enhanced by increased decomposition of phospholipids; PA serves as a secondary messenger involved in plant biological process regulation and the reduction in the reactive oxygen species- and peroxide-induced damage caused by salt stress. The possible mechanism of action is via promoted plant osmotic regulation and tolerance to salt stress, reducing salt stress-induced injury to plants. [ABSTRACT FROM AUTHOR]

• Peach had a higher utilization rate of glycine compared with urea. • Glycine:urea (7:3) treatments significantly increased the biomass of peach. • Glycine and glycine:urea (7:3) treatments led to higher rubisco activity in leaves. • High-dose of glycine promoted the accumulation of sucrose in leaves and fruits. The unreasonable use of urea and its low nitrogen use efficiency limit peach fruit yield and quality. In this study, six different fertilization treatments—no nitrogen fertilizer, urea (T1), glycine (T2), glycine:urea (1:1) (T3), glycine:urea (3:7) (T4), and glycine:urea (7:3) (T5)—were used to explore the effects of glycine and urea on the growth, photosynthesis, sucrose metabolism, and fruit development of peach. Peach had a higher utilization rate of glycine compared with urea; combined application of glycine-urea improved the utilization rate of urea compared with T1. T5 significantly increased the biomass of peach. High-dose glycine (T2 and T5) promoted the opening of stomata and the efficiency of photosynthetic electron transfer, which increased the net photosynthetic rate (P n). In addition, the activity of Rubisco was higher in leaves on wild peach treated with T2 and T5, which increased the fixation of CO 2. Under high-dose glycine treatment, the lower cell wall invertase activity in leaves and the higher cell wall invertase activity in fruits promoted the transfer of sucrose from source to sink. In addition, high-dose glycine treatment led to higher sucrose phosphate synthase activity in leaves and fruits, which improved the accumulation of soluble sugar in the fruit. The higher sucrose transport efficiency increased the single fruit weight, soluble solid content and ratio of sugar to acid in peach fruits under high-dose glycine treatment. [ABSTRACT FROM AUTHOR]