Journal of Fruit Science

【Objective】The study aimed to explore the absorption and translocation patterns of exogenous selenium in different organs of apple trees. After applying selenium-enriched organic fertilizer and an equal amount of non-selenium-enriched organic fertilizer to Ruixue apple trees, we measured the total selenium, organic selenium, and inorganic selenium contents in various organs of the apple trees in order to provide a theoretical basis for the scientific production of selenium-enriched apples.【Methods】Taking Ruixue apple trees (with T337 as the rootstock) as experimental materials, a controlled pot experiment was conducted. During the fruit enlargement period, apply 0.05 kg per plant of selenium-enriched organic fertilizer evenly in the ring-shaped groove. An equal amount of non-selenium-enriched organic fertilizer was used as the control (CK) . At the fruit maturity stage, the whole fruits, leaves, later al branches, main trunk, underground stem segments of the rootstock, and underground fibrous roots of the trees were collected via destructive sampling. Each organ was excised, brought back to the laboratory, rinsed with deionized water, dried in an oven at 105℃ for 30 minutes, and then baked at 80℃for 8 hours. After that, the dry mass of each organ was weighed using a balance. Each organ was crushed using a grinder and sealed in a bag for the determination of total selenium and inorganic selenium content using fluorescence spectrophotometry. After the soil samples were naturally air-dried, they were crushed using a grinder, passed through a 100-mesh sieve, and then placed in sealed bags for the determination of total selenium and available selenium content by fluorescence spectrophotometry. By comparing indicators such as total selenium, organic selenium, and inorganic selenium content in various organs, the absorption, translocation, and distribution patterns of exogenous selenium in different tree organs were determined.【Results】After the application of exogenous selenium, the total selenium and organic selenium contents in all organs of Ruixue apples gradually decreased from the underground fibrous roots to the fruits (i.e., from the bottom to the top of the plant) . Specifically, the order of total selenium content from high to low was: underground fibrous roots ＞ the underground stem segment of the rootstock ＞ main trunk ＞ lateral branches ＞ leaves ＞ fruits. The order of organic selenium content from high to low followed the same pattern: underground fibrous roots ＞ the underground stem segment of the rootstock ＞ main trunk ＞ lateral branches ＞ leaves ＞ fruits. By contrast, the order of inorganic selenium content from highest to lowest was: leaves ＞ underground fibrous roots ＞ lateral branches ＞ main trunk ＞ the underground stem segment of the rootstock ＞ fruits. The percentage of organic selenium in each organ reached over 60%. The total selenium accumulation, ranked from highest to lowest, was as follows: main trunk ＞ underground fibrous roots ＞ the underground stem segment of the rootstock ＞ fruits ＞ leaves ＞ lateral branches. Sorted by enrichment coefficient from largest to smallest, the order was as follows: underground fibrous roots ＞ the underground stem segment of the rootstock ＞ main trunk ＞ lateral branches ＞ leaves ＞ fruits. Sorted by distribution rate from largest to smallest, the order was as follows: main trunk ＞ underground fibrous roots ＞ the underground stem segment of the rootstock ＞ fruits ＞ leaves ＞ lateral branches. The transport coefficients sorted from largest to smallest were as follows: TF Soil-Underground fibrous roots ＞ TF Main trunk-Lateral branches ＞ TF Lateral branches-Leaves ＞ TF Underground fibrous roots-Main trunk ＞ TF Leaves-Fruits ＞ TF Underground fibrous roots-The underground stem segment of the rootstock. Among all organs of Ruixue apples in the CK treatment, total selenium content was the highest in underground fibrous roots. The total selenium content from high to low was as follows: Underground fibrous roots ＞ lateral branches ＞ main trunk ＞ the underground stem segment of the rootstock ＞ leaves ＞ fruits, and the organic selenium content, from highest to lowest, was as follows: underground fibrous roots ＞ main trunk ＞ lateral branches ＞ fruits ＞ leaves ＞ the underground stem segment of the rootstock. The inorganic selenium content, ranked from highest to lowest, was as follows: underground fibrous roots ＞ the underground stem segments of the rootstock ＞ lateral branches ＞ leaves ＞ main trunk ＞ fruits. The percentage of organic selenium in each organ was significantly lower than that of CK. The total selenium accumulation, ranked from highest to lowest, was as follows: underground fibrous roots ＞ main trunk ＞ fruits ＞ leaves ＞ the underground stem segment of the rootstock ＞ lateral branches. The enrichment coefficients, sorted from largest to smallest, were as follows: underground fibrous roots ＞ lateral branches ＞ main trunk ＞ the underground stem segment of the rootstock ＞ leaves ＞ fruits, and the distribution rate from largest to smallest was as follows: underground fibrous roots ＞ fruits ＞ leaves ＞ the underground stem segment of the rootstock ＞ lateral branches. The transport coefficients sorted from largest to smallest were as follows: TF Soil-Underground fibrous roots ＞ TF The underground stem segment of the rootstock-Main trunk ＞ TF Main trunk-Lateral branches ＞ TF Leaves-Fruits ＞ TF Lateral branches-Leaves ＞ TF Underground fibrous roots-The underground stem segment of the rootstock. Except that the inorganic selenium content in the underground stem segment of the rootstock under exogenous selenium treatment was lower than that of CK, exogenous selenium treatment significantly increased the total selenium content, organic selenium content, inorganic selenium content, and the percentage of organic selenium in each organ of Ruixue apples compared with CK. Under selenium treatments, total selenium accumulation, enrichment coefficient, distribution rate and translocation coefficient were all higher in fibrous roots, reaching 19.31 µg, 236.44%, 35.99% and 236.46%, respectively for the CK group, fibrous roots also exhibited the highest total selenium accumulation, enrichment coefficient, and translocation coefficient, which were 6.78 µg, 172.75%, and 172.74%, respectively. Exogenous selenium application significantly increased both total soil selenium content and available soil selenium content.【Conclusion】Compared with the application of selenium-organic fertilizer, exogenous selenium application increased the selenium content in different organs of the tree. The selenium content in fruits reached 60.67 µg · kg-1, meeting the standard for selenium-enriched apples (30 µg · kg-1) . Therefore, selenium-enriched apples could be produced by properly applying exogenous selenium.

【Objective】The collection, evaluation, and rational utilization of sea buckthorn germplasm resources form the foundation for breeding superior varieties and developing effective production practices. Qinghai Province possesses an abundance of sea buckthorn germplasm resources. This study aimed to investigate the genetic diversity of fruit and seed phenotypic traits among local and introduced sea buckthorn varieties in alpine region of Qinghai, with the objective of identifying germplasm exhibiting exceptional seed and fruit characteristics.【Methods】This study systematically evaluated the phenotypic traits of fruits and seeds from 36 sea buckthorn germplasm samples collected in alpine region of Qinghai. The aim was to establish a reference for assessing fruit quality, improving germplasm breeding, and supporting the sustainable development of the sea buckthorn industry in Qinghai Province. Evaluated quality traits included fruit shape, seed shape, seed coat color, and grooves, while quantitative traits encompassed berry stalk length, berry longitudinal and transverse diameters, berry shape index, berry volume, single berry weight, seed length and width, seed shape index, seed volume, 1000grain weight, exocarp and endocarp mass, as well as exocarp and endocarp thickness. Subsequent analyses included diversity, correlation, and cluster analyses of these phenotypic traits, culminating in a comprehensive evaluation through principal component analysis.【Results】The fruits and seeds of 36 sea buckthorn germplasms exhibited significant genetic diversity, with quality traits showing a diversity in dex ranging from 0 to 1.14. Fruit shapes displayed the highest variation types and the largest diversity index, while seed grooves exhibited the smallest diversity index, present in all germplasm seeds. It indicated that the distribution of this trait was relatively stable among different description types. Among the 36 sea buckthorn germplasms, oblate ones were the most common, accounting for 40.74%, followed by round ones, accounting for 38.43%, and cylinder ones had the lowest proportion, only 2.78%. The coefficient of variation for the 15 quantitative traits varied from 11.46% to 68.42%. Notably, exocarp thickness and endocarp mass demonstrated substantial variation, with coefficients of variation exceeding 60%, and berry stalk length, berry volume, single berry weight, seed volume, exocarp mass, and endocarp thickness, were all above 30%, indicating considerable dispersion of phenotypic traits among different sea buckthorn germplasms. The diversity index for quantitative traits ranged from 1.25 to 2.08. Berry stalk length, berry transverse diameter, single fruit weight, seed length and width, seed shape index, seed volume, 1000-grain weight, and endocarp thickness all exhibited diversity indices exceeding 2.00, classifying them as highly variable traits. The genetic diversity index for the remaining traits fell between 1.00 and 2.00. The correlation analysis revealed intricate and strong correlations among diverse phenotypic traits in different sea buckthorn germplasms. Subsequent cluster analysis categorized 36 sea buckthorn germplasm resources into three distinct groups: the first group featured medium-sized fruits with thin and light fruit skins; the second group exhibited small fruits with thick fruit skins; the third group showcased large fruits with elongated fruit stalks. The principal component analysis demonstrated that the cumulative contribution rate of the three principal components identified was 80.011%. Specifically, the first principal component primarily reflected the quality and shape of fruits and seeds, the second principal component predominantly characterized the exocarp thickness, and the third principal component was mainly associated with the endocarp thickness. The comprehensive assessment indicated that the highest overall score was recorded in 2013-05 (5.510) .【Conclusion】The variation in fruit and seed quality traits among sea buckthorn germplasms in alpine region of Qinghai is relatively extensive, and the diversity index for quantitative traits is notably high. Through a combination of correlation analysis and principal component analysis, five key indicators for assessing sea buckthorn plant traits are identified: berry longitudinal diameter, seed length, single fruit weight, 1000-grain weight, and berry peel thickness. These indicators can serve as crucial reference points for subsequent quality analysis, evaluation of sea buckthorn germplasm resources, and variety breeding efforts. The comprehensive scores of fruit and seed phenotypic traits of six sea buckthorn germplasms namely 2013-05, Zayou No. 2, Fuza, LJ-10-03, LJ-10-56, and Zayou No.1, rank among the highest as a result of integrating various evaluation methods, and are suitable for breeding sea buckthorn varieties and for the rational development and utilization in alpine region of Qinghai.

【Objective】TCP transcription factors (TFs) are a class of plant-specific TFs that play a crucial regulatory role in processes such as seed germination, vegetative growth, flowering, fruit development, senescence, and stress response in plants. To date, although the TCP family has been extensively studied in model plants such as Arabidopsis thaliana and rice, there have been no systematic reports on this gene family in Prunus avium L., a globally important economic fruit crop. This study aims to conduct a comprehensive genome-wide identification and systematic expression analysis of the TCP family in sweet cherries, with a focus on exploring its stress (drought, salt and iron deficiency) resistance functions.【Methods】The latest genome sequences, protein sequences, and GFF3 annotation files of the sweet cherry cultivar Tieton v2.0 were retrieved from the Rosaceae Genome Database (https://www.ro saceae.org/) , a widely recognized repository for genomic resources of species in Rosaceae. A series of bioinformatics tools and pipelines were employed to characterize the TCP family members. Then, Ex-PASy ProtParam was used to analyze physicochemical properties (such as molecular weight, isoelectric point, instability index) ; MEGA 11 was utilized to construct a neighbor-joining phylogenetic tree with 1000 bootstrap replicates; Gene Structure Display Server (GSDS 2.0) was used to visualize gene structures (exons, introns, and UTRs) ; MEME Suite (v5.5.3) was conducted to identify conserved motifs. In addition, TBtools was used to map genes to chromosomes and analyze syntenic relationships; and Plant-CARE was used to predict cis-acting elements in the 2000 bp upstream promoter regions. For expression analysis, in vitro rooted plantlets of Gisela 17, a commonly used rootstock with good adaptability, were subjected to three abiotic stress treatments: drought, salt, and iron deficiency. Total RNA was extracted from leaves using TRIzol reagent at 0, 12, 24, 48 and 72 hours after treatment, and the first strand cDNA was synthesized by reverse transcription using PrimeScript RT kit. Quantitative real-time PCR (qRT-PCR) was performed to analyze the gene expression levels.【Results】Candidate genes were further verified by domain confirmation via the SMART and NCBI CDD databases to exclude sequences with incomplete or truncated domains, resulting in the final identification of 19 TCP family members, designated as PaTCP1-PaTCP19 based on their chromosomal locations. These genes were unevenly distributed across 8 of the 16 sweet cherry chromosomes. The coding sequences of PaTCP genes ranged from 268 to 601 amino acids (aa) , with corresponding molecular weights of 29.87-66.73 kDa. The isoelectric points (pI) varied from 6.14 to 9.51, including 10 alkaline proteins (pI＞7) and 9 acidic proteins (pI＜7) . The instability index ranged from 48.14 to 78.73, indicating all PaTCP proteins are unstable (instability index ＞ 40) , while the aliphatic index (52.28-87.44) and negative hydrophobicity values confirmed their hydrophilic nature, consistent with their predicted nuclear (PaTCP1-17) , mitochondrial (PaTCP18) , and cytoplasmic (PaTCP19) localization. Motif analysis revealed 10 conserved motifs, among which motif 1 (corresponding to the core TCP domain) was present in all 19 PaTCP proteins, highlighting its high conservation. Gene structure analysis indicated 8 PaTCP genes contained a single exon, 4 had two or more exons, and 7 lacked untranslated regions (UTRs) , with intron numbers ranging from 1 to 5. Phylogenetic analysis of 19 sweet cherry TCP proteins and 24 Arabidopsis TCP proteins classified PaTCP members into two major clades: ClassI (PCF subfamily, 10 genes) and ClassⅡ (9 genes total, including 7 in the CIN subfamily and 2 in the CYC/TB1 subfamily) . Synteny analysis identified 6 pairs of homologous PaTCPs (PaTCP1-PaTCP9, PaTCP2-PaTCP15, PaTCP4-PaTCP5, PaTCP5-PaTCP14, PaTCP4-PaTCP14) , all derived from segmental duplication (no tandem duplication events were detected) , indicating large-fragment duplication as the primary mechanism driving the expansion of PaTCP family. The Ka/Ks ratios of all homologous gene pairs ranged from 0.13 to 0.29 (all＜1) , suggesting strong purifying selection during evolution to maintain functional stability. The TCP genes in sweet cherries show significant selective conservation in evolution, which maintain a high degree of linearity with dicotyledonous model plants and closely related stone fruit trees. Among them, 32 pairs and 22 pairs of homologous genes were identified in Arabidopsis thaliana and tomato, respectively, while the collinear logarithms with peach, plum and apricot reached 38 to 40 pairs, confirming the closer evolutionary distance and more complete preservation of chromosomal segments within stone fruit trees. In contrast, the collinear relationship with the monocotyledonous plant rice is only 13 pairs, and the evolutionary distance between the two is relatively far. Promoter cis-acting element analysis identified 7 types of functional elements in the 2000 bp upstream regions of PaTCP genes, including abiotic stress-responsive elements (low temperature, drought, defense and stress) and hormone (gibberel lin, salicylic acid, methyl jasmonate, auxin, abscisic acid) -responsive elements, indicating potential involvement of PaTCP genes in multiple stress and hormone signaling pathways. qRT-PCR results showed PaTCP6 was the only gene with no significant expression changes under all the three stresses at all time points, while most other PaTCP genes exhibited similar response patterns across different stresses. Specifically, PaTCP1, PaTCP3, PaTCP4, PaTCP7, PaTCP9, PaTCP10, PaTCP15, PaTCP17, PaTCP18, and PaTCP19 were significantly upregulated under drought, salt, and iron deficiency, with the most dramatic upregulation observed at 24 h and 48 h post-treatment (fold changes ranging from 2.3 to 12.7) . In contrast, PaTCP2, PaTCP8, PaTCP11, PaTCP12, PaTCP13, and PaTCP16 were consistently downregulated under three stresses, while PaTCP14 showed no significant change under drought but exhibited significant upregulation under salt and iron deficiency stresses (fold changes of 3.1 and 4.5 at 48 h, respectively) , indicating its specific role in responding to salt and ionic stresses.【Conclusion】The research results indicate that the PaTCP genes play an"activation-inhibition"regulatory role under various abiotic stresses (such as drought, salt stress, and iron deficiency) , and different members exhibit either conserved or specific response patterns. The stress-responsive PaTCP genes identified in this study provide valuable candidate resources for genetic improvement of stress resistance in sweet cherry via molecular breeding approaches.

In the reproductive biology of fruit trees, male sterility, as an important agronomic trait, is directly related to pollination efficiency and breeding strategies. In the industry, this trait has been utilized for the selection of new varieties and the production of seedless fruits. According to different genetic modes, it is usually manifested as cytoplasmic male sterility (CMS) and nuclear male sterility (GMS) . GMS is controlled by a single or a few genes in the nuclear genome and follows Mendelian inheritance laws, while CMS is usually caused by the interaction between genes in the mitochondrial genome and nuclear genes, and exhibits non-Mendelian inheritance characteristics. Male sterility in peach and apricot is of the GMS type, controlled by the Ps and Ms genes, respectively, while citrus belongs to the CMS type. Male sterility affects the efficient and labor-saving cultivation of fruit trees and the progress of seedless breeding. The physiological and molecular mechanisms of male sterility in fruit trees remain unknown. Male sterility in fruit trees exhibits diverse morphological manifestations, primarily including pollen abortion, abnormal tapetum structure, anther degeneration, stamen degeneration or morphological abnormality, microsporangium degeneration, and microspore degeneration, etc. Male sterility in fruit trees can be identified through visual inspection, the staining method, the pollen in vitro culture method, and in vivo identification. As a specific tissue that directly contacts microspores, the tapetum undergoes programmed cell death (PCD) during its development. Abnormalities in the structure or function of the tapetum are one of the key factors leading to male sterility in fruit trees. Tapetal programmed cell death (PCD) provides necessary enzymes, sporopollenin precursors, and other nutrients for the normal maturation of microspores and the formation of the pollen exine. During pollen development, the ability of carbohydrates, other nutrients, plant hormones, and antioxidant systems to remove free radicals significantly affects fertility. In addition, abnormal mitosis and meiosis of microspores during pollen development can also cause male sterility in apricots and citrus. Environmental factors, such as extreme temperatures (either too high or too low) , insufficient light, drought or flooding stress, and pollutants in the air or soil, can also affect pollen fertility in fruit trees. During the process of microspore formation in peach, the genes regulating male sterility include the PpABCG26, PpCYP703A2, Pp4CL, and Prupe.6G025000 (CLSE6) . In grape, the VvMs1, Vvms2, VviINP1, and VviPPR are involved in the regulation of microspore development. The Pbr035883.1 regulates the microspore development in pear. The genes Barnase, CgAP3.2, and CrMER3 affect pollen development in citrus fruits. The CmTAR regulates pollen development in chestnut. The ATP1 regulates pollen development in jujube. PmGRF7 regulates the formation of male sterility in plum. Additionally, methylation affects the pollen fertility in citrus. This study not only summarizes the research progress on the manifestation forms, identification methods, genetic studies, physiological mechanisms, and gene mining of male sterility in deciduous fruit trees such as peach, pear, grape, cherry, jujube, and chestnut, but also reports the research progress on the physiological mechanisms and gene mining of cytoplasmic male sterility in citrus. However, there are few reports on the molecular mechanisms of male sterility in fruit trees. While extensive research on pollen development in many species has focused on the synthesis and transport of sporopollenin, a comprehensive mechanistic understanding of pollen abortion at the molecular level is perhaps best exemplified by studies in citrus. The miR159a-DUO1 module regulates citrus pollen development by modulating auxin biosynthesis and starch metabolism. In the process of peach pollen development, a possible transcriptional regulatory mechanism involving DYT1-TDF1-AMS-MS188-MS1 exists. The polymerization and establishment of sporopollenin involve two crucial steps: synthesis and transport. The synthesis of sporopollenin refers to the synthesis and secretion of its precursors, while its transport refers to the final delivery to the microspores and the formation of the fine exine structure on the microspores. Sporopollenin is produced and accumulated in the tapetum by Acyl-CoA synthetase 5 (ACOS5) , while typeⅢlipid transfer proteins (LTPs) function as components to transport it from the tapetum to the pollen exine. In the future, research on male sterility in fruit trees will focus on the exploration of male sterility genes and the analysis of their molecular mechanisms. Subsequently, it will involve the study of the mechanisms through which environmental factors influence the expression of these sterile genes. This study can offer significant theoretical support for the simplified cultivation of fruit trees and the breeding of new germplasm.

【Objective】Flower buds of Diospyros are mixed buds, and their differentiation involves complex morphogenetic and physio-biochemical changes that directly influence the success of subsequent flowering. Diospyros species feature diverse ploidy evolutionary trajectories, with marked developmental differences among germplasm of different ploidy levels. This study aimed to clarify the temporal formation dynamics and morphological differences of floral organ primordia among D. lotus L., D. deyangensis, and‘Xiaoguo Tianshi'through systematic observation and analysis of their floral differentiation processes. The primary objective was to reveal the morphological basis underlying early flowering in D. deyangensis, thereby providing an anatomical framework for understanding ploidy-dependent floral development in Diospyros.【Methods】Perennial female plants of D. lotus L., D. deyangensis, and‘Xiaoguo Tianshi'cultivated in the National Germplasm Repository for Diospyros of Northwest A&F University (Yangling, Shaanxi) were used as experimental materials. Sampling encompassed two critical phases of floral differentiation: the early differentiation stage of current-season flower buds (May to August 2025) and the late differentiation stage of previous-season flower buds (February to May 2025) . At the early stage, five vigorously growing new shoots from each germplasm were selected in the morning and sampled weekly to ensure consistent material quality and consistent growing environment. In the late stage, three current-year branches were collected every 4 days in the morning before flower buds emerged; after flower buds emerged, five branches were sampled every 2 days to track floral maturation. Three complementary observation techniques were employed to capture multidimensional developmental data. First, continuous external morphological observation was conducted covering three key developmental stages: early differentiation, dormancy, and flowering. Overall branch morphology was photographed using a digital camera; external phenotypic traits of mixed buds were imaged via a stereofluorescence microscope; buds were dissected under the microscope with fine forceps and dissecting needles to obtain high-resolution images of internal anatomic structures. Secondly, for scanning electron microscopy (SEM) analysis, samples collected from February to August 2025 were fixed in 2.5% FAA fixative, rinsed with phosphate buffer, and dehydrated sequentially in 30%, 40%, 50%, 70%, 90%, 100%, and 100% ethanol (15 min per gradient) . They were then subjected to solvent replacement with isoamyl acetate to preserve their structure, dried using a K850 critical point dryer, mounted on metal stubs with conductive adhesive, sputter-coated with gold for 90 s, and observed under a field emission SEM for fine-scale characterization of floral primordia. Thirdly, for paraffin sectioning, buds were incubated in a specialized fixative (85∶5∶5∶5, V/V of 70% tert-butanol, 35%-40% formaldehyde, propionic acid and glycerol) , subjected to vacuum infiltration until all gas bubbles were eliminated and the materials were fully submerged, then stored at 4℃ for ≥48 h to ensure thorough fixation. After fixation, the samples were dehydrated through an ethanol gradient, infiltrated with molten paraffin wax, embedded in paraffin blocks, and sectioned into 5-8 μm slices using a microtome. The sections were then stained with hematoxylin-eosin (HE) , mounted with neutral balsam, and observed under a light microscope to analyze internal bud development. These approaches collectively enabled systematic characterization of the dynamic development of external morphology and internal structure of mixed buds and female flowers.【Results】Comprehensive observations revealed that the three Diospyros germplasms shared a conserved centripetal sequence of floral organ differentiation and a consistent cross-annual developmental cycle: floral differentiation initiated in late May of the current year, followed by winter dormancy for low-temperature tolerance, and development resumed actively in the following spring until flowering. Inter-germplasm differences in external bud traits were observed: the bud scales of D. deyangensis and‘Xiaoguo Tianshi'were uniformly brown and densely pubescent, whereas those of D. lotus L. were dark brown to nearly black, with a thick, glossy waxy cuticle and rigid texture, suggesting enhanced abiotic resistance A distinct germplasm-specific marker was observed during the differentiation stage of stamen primordium: In D. deyangensis, the bases of stamen primordia and petal primordia displayed a stable pink hue, while those of D. lotus L. and‘Xiaoguo Tianshi'remained green. This color dimorphism persisted after flowering. The petals of D. lotus L. were creamy yellow, those of D. deyangensis were pink, and those of‘Xiaoguo Tianshi'were pale yellow. All three accessions produced solitary female flowers, but they exhibited significant differences in floral morphology. Correlation analysis showed a significant positive correlation between ploidy level and flower bud longitudinal diameter:‘Xiaoguo Tianshi'had the largest buds, followed by D. deyangensis, and D. lotus L. had the smallest. Floral differentiation initiated synchronously in late May across all three germplasms, with bract differentiation proceeding in parallel. D. deyangensis was the first to enter sepal differentiation, consistently advancing 3-5 days ahead of the other two accessions. Both bract differentiation and sepal differentiation were completed by June across all germplasms, with minimal temporal variation. However, a critical developmental divergence emerged at the petal differentiation stage: D. deyangensis and‘Xiaoguo Tianshi'completed petal primordium differentiation by late July (prior to dormancy initiation) , whereas D. lotus L. remained at the sepal primordium stage until the onset of dormancy, and did not initiate petal differentiation until March of the following year (after dormancy release) .Petal differentiation in D. deyangensis and‘Xiaoguo Tianshi'occurred 7 months earlier than in D. lotus L., which facilitated the accelerated differentiation of the subsequent stamen and carpel primordia. This temporal advantage ultimately led to an earlier initial flowering period for D. deyangensis and‘Xiaoguo Tianshi'compared with D. lotus L.【Conclusion】The early-flowering trait of D. deyangensis is linked to three pivotal developmental features: early initiation of floral differentiation, rapid differentiation progression during the pre-dormancy period, and significantly advanced petal differentiation. Among these factors, petal differentiation acts as the critical regulatory checkpoint underlying temporal differences in floral differentiation among Diospyros germplasm of varying ploidies. The 7-month advance in this stage allows D. deyangensis to complete the development of key floral organ primordia before dormancy, shortening its developmental cycle and contributing to its early-flowering phenotype.

【Objective】To clarify changes in the mineral composition of blackberry fruits, this study used organically grown blackberries at different maturity stages as raw materials. It compared wet digestion and microwave digestion methods, incorporated uncertainty analysis, and comprehensively evaluated the reliability of the experimental approach. This research would provide technical support for assessing dynamic changes in mineral elements during blackberry ripening.【Methods】Using inductively coupled plasma-mass spectrometry (ICP-MS) with dynamic collision cell mode, this study compared the sealed digestion (SD) and microwave digestion (MD) methods to investigate the dynamic changes in sodium, potassium, calcium, magnesium, copper, iron, zinc, and manganese during blackberry ripening. The following parameters were included: Spiked recovery u1 (Sm) , pipette u2 (std) , internal standard u2 (Sm) , mother liquor u1 (std) , sample repeatability u2 (Cp) , volumetric flask temperature u2 (V) , fitting u3 (std) , blank solution repeatability u1 (Cp) , volumetric flask calibration u1 (V) , volumetric flask repeatability u3 (V) , balance repeatability u2 (m) , balance calibration u1 (m) , and instrument u3 (Sm) .【Results】The correlation coefficients for the standard curves of all 8 elements exceeded 0.999, with spiked recovery rates ranging from 93.33% to 104.50%. This method demonstrated high sensitivity and precision During blackberry development, as the fruits expanded and ripened, the contents of the 8 minerals showed a significant overall downward trend: an initial decline followed by stabilization. From the green fruit stage to the color change stage, the concentrations of all 8 minerals decreased substantially, with the most pronounced changes observed in sodium, potassium, and zinc. During color change stage Ⅱ, the concentrations of sodium, iron, magnesium, calcium, zinc, and manganese increased, while those of potassium and copper decreased. During color change stageⅢ, potassium and manganese increased, while the remaining six elements decreased. At maturity, sodium, potassium and manganese decreased, while the other five elements increased to varying degrees. This indicates that all eight elements show a significant downward trend during blackberry fruit coloration, suggesting that substantial physiological changes accompany this process and significantly impact mineral absorption and metabolism. The contents of sodium, potassium, and manganese show the most pronounced decline during fruit ripening, which would provide theoretical support for water and fertilizer management in blackberry cultivation. The uncertainty values for each component during the testing process, sorted from largest to smallest, are as follows: Spiked recovery u1 (Sm) ＞ Pipette u2 (std) ＞ Internal standard u2 (Sm) ＞ Stock solution u1 (std) ＞ Sample repeatability u2 (Cp) ＞ Volumetric flask temperature u2 (V) ＞ Fitting u3 (std) ＞ Blank solution repeatability u1 (Cp) ＞ Volumetric flask calibration u1 (V) ＞ Instrument u3 (Sm) . Among the five uncertainty sources, volumetric flask repeatability u3 (Sm) has the highest uncertainty, (V) ＞ volumetric flask repeatability u3 (V) ＞ balance repeatability u2 (m) ＞ balance calibration u1 (m) ＞ instrument u3 (Sm) . For the other five uncertainty sources, the uncertainty contribution ranks as follows: sample matrix Urel (Sm) ＞ standard curve preparation Urel (std) ＞ sample preparation Urel (Cp) ＞ volume adjustment Urel (V) ＞ weighing Urel (m) . This indicates that standard curve preparation and the sample matrix are the dominant contributors to uncertainty in the determination of eight elements in blackberries by inductively coupled plasma mass spectrometry. Among these factors, spiked recovery, pipette usage, internal standards, and standard stock solutions exerted the greatest influence on the test results in this study. The expanded uncertainty coefficients for all 8 elements were below 5%, and in descending order, they are:Calcium＜magnesium＜potassium＜copper＜sodium＜iron＜manganese＜zinc. Component analysis revealed that the spiked recovery of manganese and zinc introduced relatively higher uncertainties. The combined uncertainty for the eight elements ranged from 0.011 271 to 0.022 888, with expanded uncertainty percentages as follows: sodium (2.76%) , potassium (2.54%) , calcium (2.25%) , magnesium (2.49%) , copper (2.66%) , iron (2.89%) , zinc (4.58%) , and manganese (3.12%) .【Conclusion】This study established a microwave digestion-inductively coupled plasma mass spectrometry (ICP-MS) method to determine the contents of eight minerals in blackberries. After validating the method′s linearity, detection capability, precision, accuracy, robustness, and measurement uncertainty, this research clarified the variation trends of these eight mineral contents during the fruit development of blackberries. The findings would provide data support and a theoretical basis for further relevant research.

【Objective】Soil salinization is a critical environmental factor limiting the sustainable development of agriculture and forestry worldwide. High salinity induces osmotic stress, ion toxicity, and oxidative damage in plants, leading to growth inhibition, metabolic disorders, and even mortality. Elaeagnus moorcroftii, a perennial tree species of the Elaeagnaceae family, exhibits strong tolerance to drought, salt, and wind erosion, making it a valuable species for vegetation restoration in arid and semiarid regions of Northwest China. While previous studies have explored its salt tolerance at the species level, systematic comparisons of salt tolerance among different varieties, integrating both physiological and anatomical responses, remain scarce. This study aims to evaluate the salt tolerance of six major cultivated varieties of E. moorcroftii by analyzing their physiological, biochemical, and anatomical responses under salt stress, thereby providing a theoretical basis for the selection and breeding of salt-tolerant genotypes and their application in saline-alkali land restoration.【Methods】One-year-old seedlings of six E. moorcroftii varieties (Jinsha, Bachu No.1, Baishatian, Maigaiti No.3, Celedahuang and Yafeng) were selected for the experiment. The seedlings were subjected to a gradual salt stress treatment using 500 mmol · L-1 NaCl solution, with the concentration incrementally increased every two days until a total of 2000 mL was applied. Soil electrical conductivity was monitored to maintain a target salinity level of 0.4% ± 0.1%. Control groups were irrigated with an equivalent volume of deionized water. Physiological and biochemical indicators, including malondialdehyde (MDA) , soluble sugar (SS) , soluble protein (SP) , proline (Pro) , superoxide dismutase (SOD) , peroxidase (POD) , and catalase (CAT) , were measured at 0, 5, 10, 15, 20, 25, and 30 days after stress initiation. Leaf and stem anatomical structures were examined after 25 days of stress using paraffin sectioning and microscopic imaging. Data were analyzed using SPSS 26.0 for ANOVA and Duncan's multiple range tests, and principal component analysis (PCA) was performed to comprehensively evaluate salt tolerance.【Results】Under salt stress, the contents of MDA and SS increased continuously across all varieties, indicating progressive membrane lipid peroxidation and osmotic adjustment. SP content and the activities of SOD and CAT showed an initial increase, followed by a decline, suggesting an early activation of defense mechanisms that weakened under prolonged stress. The proline (Pro) content showed a dynamic change of first increasing and then decreasing, with the most significant accumulation occurring at the 25th day. POD activity increased consistently throughout the stress period, highlighting its role in long-term oxidative stress mitigation. Anatomical observations revealed variety-specific structural adaptations. Yafeng exhibited well-developed palisade tissue, tightly arranged mesophyll cells, and robust xylem development. Baishatian showed a thickened lower epidermal cell wall and a wider vascular cambium. In contrast, Celedahuang had loose mesophyll tissue and underdeveloped vascular bundles. Leaf thickness and main vein thickness were significantly affected by salt stress, while upper and lower epidermal thickness remained largely unchanged. Stem anatomy also showed notable changes, with Yafeng displaying enhanced xylem and vascular bundle development, whereas Jinsha showed reductions in these traits. Principal component analysis identified SP, MDA, and SOD as the key indicators for salt tolerance evaluation. The first three principal components accounted for 84.98% of the total variance. Based on comprehensive scores derived from PCA, the salt tolerance of the six varieties was ranked as follows: Yafeng ＞ Baishatian ＞ Maigaiti No. 3 ＞ Bachu No. 1 ＞ Celedahuang ＞ Jinsha.【Conclusion】This study demonstrates that salt tolerance in E. moorcroftii is variety-specific and involves coordinated physiological, biochemical, and anatomical adaptations. The more salt-tolerant varieties, such as Yafeng and Baishatian, exhibited efficient osmotic regulation, strong antioxidant enzyme activity, and favorable anatomical traits such as dense mesophyll tissue, thickened epidermal layers, and well-developed vascular systems. In contrast, sensitive varieties like Jinsha showed weaker regulatory capacity and structural integrity under stress. The key indicators SP, MDA, and SOD effectively reflect the osmotic adjustment, membrane stability, and antioxidant capacity of the plants under salt stress. These findings provide a scientific basis for the selection and breeding of salt-tolerant E. moorcroftii varieties and support their use in the ecological restoration of saline-alkali lands.

【Objective】This study attempted develop a high-throughput kompetitive Allele-Specific PCR (KASP) marker targeting the sparse lateral branching in watermelon (Citrullus lanatus) , systematically validated its specificity, stability and applicability, and applied it to marker-assisted breeding (MAS) to create elite lines with reduced lateral branches and high quality, as well as to breed new varieties suitable for industrial cultivation. This study aims to reduce the high cost of manual pruning and improve the low efficiency of traditional breeding, both of which are caused by excessive lateral branching, and thereby accelerate the breeding of watermelon varieties with an ideal plant architecture.【Methods】Donor ZXG1361 (homozygous mutant AA, reduced lateral branches) and recipients FLW03Z01/FLW03Z02 (homozygous wild-type CC, normal lateral branches) were used to construct F1, F2, F3, and F4 populations, grown at two experimental stations (2023—2025) under uniform protected cultivation. Lateral branch number (≥2 cm) , plant height, and internode number were investigated at 30 and 45 days after transplanting; chi-square test verified F2 segregation ratio, and T-test (α=0.05) analyzed parental phenotypic differences. Genomic DNA was extracted from cotyledons via CTAB method. Based on the C/A SNP at position 1334 of the Clbl gene, KASP marker FLB-K1 was developed, comprising FAM-labeled primer for CC genotype, HEX-labeled primer for AA genotype, and a common reverse primer. PCR was performed in 384-well plates; fluorescence signals were detected with a Pherastar scanner, and genotype-phenotype concordance was analyzed via Fisher's exact test. A multi-generation al MAS system was established: F2 seedlings with AA genotype were selected by FLB-K1, followed by phenotypic (lateral branch number≤7 per plant) and quality (central soluble solids≥10%) screening; F3/F4 populations were further screened for stable traits (lateral branch number≤5 per plant, central soluble solids≥10.5%) . Two elite F4 lines (SC-3711-③and SC-5352-①) were crossed to breed hybrid Shaocha No.1, with Zhongmi No.1 as control for trait comparison.【Results】F1 plants exhibited normal branching, confirming dominant inheritance of the normal trait. The F2 populations of AF2 (693 plants) and BF2 (390 plants) showed segregation ratios of 3.03∶1 (χ2=0.012, P=0.913) and 3.11∶1 (χ2=0.085, P=0.770) for normal vs. reduced lateral branches plants, respectively, indicating control by a single recessive gene. FLB-K1 achieved clear and distinct genotyping in F2 populations, with blue clusters for CC genotype, red for AA genotype, green for CA genotype, and no cross-contamination with blank controls. Genotype-phenotype concordance rates reached 98.28% (681/693) in AF2 and 98.97% (386/390) in BF2, with un-typable samples accounting for only 0.8% and 0.5% respectively, demonstrating high specificity and stability. Compared with traditional dCAPS markers, FLB-K1 eliminated restriction enzyme digestion and electrophoresis steps, avoiding misjudgment caused by incomplete digestion, and shortened the screening cycle from over 30 days after transplanting to a few days within the 1-leaf stage, and improved detection throughput by 4 times via 384-well plates compared with 96-well plates for dCAPS markers. Multi-generational MAS maintained 100% AA genotype homozygosity across F2 to F4 generations. F4 lines showed stable traits of sparse lateral branching (2-5 per plant) and significantly improved quality, with central soluble solids of 10.5%-13%, which was 2.5%-4% higher than donor ZXG1361 (8%-9%) . Five elite homozygous lines were successfully created, among which SC-3711-③had 2-4 lateral branches per plant, a fruit weight of 5.4-6.5 kg, a peel thickness of 0.6-0.8 cm, and central soluble solids up to 13%; SC-5352-①had 2-5 lateral branches per plant, a fruit weight of 5.3-5.9 kg, and central soluble solids 11%-12%; Shaocha No.1 had 2-5 lateral branches per plant at 45 days after transplanting, which was significantly fewer than the control Zhongmi No.1 (19-25 branches per plant, P＜0.001) , completely eliminating the need for manual pruning. Its central soluble solids reached≥12%, fruit weight 4.0-6.5 kg. It had tender flesh with medium fiber content, and a peel thickness of 0.7-1.0 cm, with comprehensive agronomic traits comparable to the control, while showing obvious advantages in simplified cultivation.【Conclusion】The developed FLB-K1 marker enables accurate, high-throughput genotyping for the watermelon with sparse lateral branch trait at the seedling stage, displaying superior performance to traditional dCAPS markers in operation simplicity, detection efficiency and stability. Application of FLB-K1 in multi-generational MAS successfully yielded five elite homozygous lines integrating traits of sparse lateral branching and high quality, solving the problem of poor quality in existing reduced lateral branch materials. The bred hybrid Shaocha No.1 combines excellent quality traits and simplified cultivation advantages, meeting the demand for industrial watermelon production. This marker and the corresponding multi-generational MAS system effectively enhanced the breeding efficiency of watermelon ideal plant architecture, providing important variety support and technical guarantee for simplified cultivation of watermelon.

【Objective】The citrus industry, a vital component of global horticulture, faces persistent challenges in rootstock production. Poncirus trifoliata, the most widely utilized citrus rootstock, conventionally undergoes high-density sowing in autumn, with transplanting delayed until the following spring. This prolonged high-density growth phase often leads to suboptimal seedling development, particularly inadequate stem diameter, which reduces grafting success. This study aimed to evaluate an innovative cultivation protocol—transplanting at the seedling emergence stage—as a viable alternative. The primary objective was to conduct a holistic comparison against the conventional method, evaluate its effects on morphological development, physiological vitality, and economic viability, to establish an evidence-based protocol for producing high-quality rootstocks.【Methods】The control group (CK) followed standard nursery practices: seeds were sown in beds filled with a commercial nursery substrate. For the experimental treatment, seeds were sown in seedling trays filled with vermiculite. The key dif ference between treatments was the timing of transplanting seedlings into their final nursery pots. CK seedlings underwent this process 240 days after sowing, in late March to early April, which aligns with common commercial production practices. In contrast, the treated seedlings were transplanted immediately after emergence, once they reached approximately 3 cm in height, and this entire process was completed within a few weeks of sowing in August. Both groups were subsequently maintained under identical, optimal growth conditions, including following a standardized fertigation schedule. A comprehensive dataset was collected periodically until 390 days after sowing. This dataset included quantitative metrics for emergence, growth (height, stem diameter and branching) , leaf development (number, size and area) , and root system architecture, all of which were analyzed through digital scanning. We assessed plant vitality by measuring biomass partitioning (the fresh and dry weights of shoots and roots) , as well as key physiological indicators such as root activity and in situ chlorophyll fluorescence (ΦPSⅡ, Fv′/Fm′, NPQ) . A detailed activity-based cost analysis was performed, considering material inputs (substrate and vermiculite) and labor time for sowing and transplanting operations, with all data normalized to the cost of producing 10 000 viable seedlings.【Results】This treatment method demonstrated clear superiority across multiple dimensions, with significant improvements observed during the seedling emergence phase. The treatment group initiated emergence 1-2 days earlier and achieved a final stand establishment rate of 76.75%, which was substantially higher than the control′s 63.25%. This suggests that the vermiculite medium would provide a more favorable germination microenvironment. Morphologically, the advantages were profound and sustained. From the initial measurement at 90 days until the study concluded at 390 days, treatment seedlings consistently exhibited greater plant height, stem diameter (critical for grafting at both 1.5 cm and 10 cm heights) , and branch number. This consistent lead indicated a powerful early start that was maintained over time. Leaf development followed suit, with the treatment producing significantly more, larger leaves. This is evidenced by the significantly greater leaf width and area measured in mature functional leaves at 390 days. The treatment group showed an early advantage in terms of root growth, with significantly greater total root length, surface area, and number of root tips at 90 and 240 days. Although the CK seedlings exhibited compensatory root growth after delayed transplanting, which narrowed the gap by 390 days, the initial advantage of the treatment group in root architecture likely contributed to its sustained aboveground vigor. Biomass accumulation mirrored these trends, with the treatment producing significantly more total biomass (in terms of both fresh and dry weight) at the early and mid-growth stages. By the end of the trial, the treatment group maintained a significant advantage in aboveground fresh mass, while other biomass metrics showed a positive, though not statistically significant, trend. Physiological assessments provided further evidence of enhanced vitality. Root activity was higher in the treatment group. More importantly, chlorophyll fluorescence kinetics measured during the peak photoperiod (09:00—11:00 am) revealed that treated seedlings operated with higher photochemical efficiency (ΦPSⅡ, Fv′/Fm′) while dissipating less excess energy as heat (lower NPQ) . This indicates a more efficient, less stressed photosynthetic apparatus that is capable of utilizing light more effectively for growth, rather than for photoprotection. Our economic analysis provided a compelling case for adoption. Using vermiculite for sowing and transplanting tiny, easyto-handle seedlings dramatically simplified the process and resulted in substantial labor savings. The largest cost savings came from the transplanting operation itself: handling young seedlings reduced labor time by 37.85% (saving 26.8 seconds per plant) . Overall, it was calculated that producing 10 000 seedlings with the tested treatment cost 18 780 yuan, compared with 21 550 yuan for the CK, representing a direct cost saving of 2770 yuan.【Conclusion】This study provides conclusive evidence that trans planting Poncirus trifoliata at the seedling emergence stage is a far more effective cultivation strategy than the conventional delayed transplanting method. By circumventing the debilitating phase of highdensity competition early in the life cycle, the treatment protocol promotes the development of superior morphology, enhanced physiology and greater economic viability in the rootstocks. The resulting seedlings have thicker stems, a critical quality trait for grafting, and exhibit enhanced overall vitality. Combined with a significant reduction in production costs, this method makes a compelling case for transforming citrus nursery practices.

【Objective】By developing species-specific molecular markers for mulberry, we systematically dissected the genetic diversity of mulberry germplasm resources. This approach would provide a solid foundation for accurate germplasm identification, analysis of genetic relationships, and selection of core germplasm collections. Ultimately, it facilitates the efficient utilization of breeding materials, supports germplasm innovation, and thus accelerates the development of elite mulberry varieties.【Methods】In this study, 46 mulberry germplasm resources were used as test materials, and Indel primers were designed and screened based on mulberry genome resequencing data. The InDel-PCR reaction system was optimized via single-factor and orthogonal experiments to ensure the accuracy of PCR results. Subsequently, genetic diversity analysis was conducted on the test materials using the optimized system and the selected primers. The experimental procedure involved collecting 46 representative mulberry germplasm resources, extracting genomic DNA, and performing genome resequencing. Indel primers were designed from resequencing data. Single-factor experiments were conducted to explore the optimal concentration ranges of PCR components: (Buffer with Mg2+, dNTPs, primers, Ta q DNA polymerase, template, and ddH2O. Orthogonal experiments were then performed to determine the optimal combination of these components. Finally, the optimized reaction system and polymorphic primers were used to amplify the genomic DNA of 46 mulberry germplasm resources, which enabled genetic diversity analysis based on the amplification results.【Results】The final optimal InDel-PCR reaction system was determined to consist of 2.0 μL of Buffer (containing Mg2+) , 0.4 μL of dNTPs, 0.8 μL each of upstream and downstream primers (10 μmol · μL-1) , 0.25 μL of Ta q DNA polymerase, 1 μL of DNA (50 ng · μL-1) , and 14.75 μL of ddH2O. The amplification program was set as follows: initial pre-denaturation at 95℃ for 3 min, followed by 30 cycles of denaturation at 94℃for 30 s, annealing at 58℃for 60 s, and extension at 72℃for 60 s, with a final extension at 72℃for 10 min, and the reaction product was stored at 4℃. This reaction system and amplification protocol demonstrated good stability and repeatability, ensuring the smooth conduct of subsequent experiments. From the 42 pairs of designed primers, 17 pairs with polymorphism and clear bands were screened out. These screened primers could effectively distinguish different mulberry germplasm resources and provide reliable tools for genetic diversity analysis. Using these 17 pairs of primers, a total of 37 polymorphic loci were detected. For each locus, the observed number of alleles (Na) was 2.0, the effective number of alleles (Ne) averaged 1.524, and Shannon′s information index (I) ranged from 0.112 5 to 0.692 0, with an average of 0.470 1. Nei′s genetic diversity (h) ranged between 0.023 7 and 0.499 7, with an average of 0.374 1, and the average observed heterozygosity (Ho) and expected heterozygosity (He) were 0 and 0.308 8, respectively. These data indicated that the tested mulberry germplasm resources exhibited rich genetic diversity, providing a solid genetic foundation for germplasm innovation and variety improvement.【Conclusion】Using the optimized InDel-PCR reaction system for Morus (mulberry trees) and the UPGMA (Unweighted Pair Group Method with Arithmetic Mean) cluster analysis, the tested mulberry materials were classified into six major groups. The results revealed the complex geographic genetic relationships among different mulberry germplasm resources. These research findings can provide a scientific basis for improving the mulberry molecular marker database, identifying mulberry germplasm resources, and conducting molecular-assisted breeding for mulberry.

【Objective】Plum (Prunus salicina Lindl.) , a woody plant of the Rosaceae family, is rich in organic acids, vitamins, carotenoids, proteins, and mineral elements such as iron and calcium. The Zhenzhu Li plum cultivated in Tian′e County, Guangxi, is an important local economic crop. However, leaf blight severely affects its yield and fruit quality, posing a major challenge to the sustainable development of the plum industry. Field observations revealed that the Mihuang Li cultivar exhibits strong resistance to leaf blight, whereas Zhenzhu Li is susceptible. This study aims to compare the rhizosphere microbial community compositions as well as the functional differences between the resistant (Mihuang Li, TA) and susceptible (Zhenzhu Li, TB) cultivars under the same environmental conditions, aiming to elucidate the mechanisms underlying the high disease resistance of Mihuang Li and to identify potential antagonistic microorganisms, thus providing theoretical and technical support for developing an ecological control system against plum leaf blight.【Methods】The experiment was conducted in a Zhenzhu Li plum orchard in Tian′e County, Hechi City, Guangxi. Rhizosphere soil samples were collected from three healthy trees per cultivar (TA and TB) around the canopy drip line in four directions. Samples were processed for DNA extraction, and high-throughput sequencing of bacterial 16S rRNA (V3-V4 region) and fungal ITS regions was performed on the Illumina MiSeq PE300 platform (Majorbio BioPharm Technology Co., Ltd., Shanghai, China) . PCR amplicons were purified, quantified, and sequenced (2 × 300 bp) . Data were analyzed using QIIME for diversity metrics, PICRUSt2 for COGbased bacterial functions, FUNGuild for fungal guilds, and IBM SPSS Statistics 21 for statistical comparisons (Duncan′s multiple range test, P＜0.05) .【Results】At the bacterial phylum level, the dominant phyla in the TA rhizosphere were Proteobacteria, Actinobacteriota, Acidobacteriota, and Chloroflexi, with Verrucomicrobiota and WPS-2 uniquely detected in TA. In contrast, TB was dominated by Actinobacteriota, Proteobacteria, Acidobacteriota, and Chloroflexi, with Bacteroidota and Methylomirabilota uniquely detected. At the genus level, TA showed higher relative abundances of Bradyrhizobium and Acidothermus, whereas TB was enriched in Arthrobacter. For fungi, TA was dominated by Ascomycota, Basidiomycota, and Mortierellomycota, while Rozellomycota was uniquely detected in TB. At the genus level, Trichoderma, Apiotrichum, and Solicoccozyma were detected only in TA, whereas TB showed higher relative abundances of Fusarium, Neocosmospora, and Chordomyces. COG-based functional prediction showed that TA had higher relative abundances of functional categories related to cell motility, secondary metabolite biosynthesis, lipid metabolism, and energy production and conversion, whereas TB exhibited higher abundances of categories associated with cytoskeleton formation, RNA processing, carbohydrate metabolism, and defense mechanisms. FUNGuild analysis revealed that TA rhizosphere fungi were mainly classified as saprotrophic guilds, while TB harbored a higher proportion of plantpathogenic guilds.【Conclusion】The rhizosphere microbial community of the resistant cultivar Mihuang Li (TA) differs significantly from that of the susceptible cultivar Zhenzhu Li (TB) in both composition and predicted function. TA harbors beneficial microorganisms such as Bradyrhizobium and Trichoderma, which exhibit strong saprotrophic activity and potential antagonism against pathogens, as well as enrichment in metabolic pathways related to energy production and secondary metabolism. These features may contribute to enhanced host resistance by maintaining rhizosphere ecological balance and suppressing pathogen colonization. In contrast, the TB rhizosphere community is dominated by potential pathogens (Fusarium, Gibberella) and decomposers, making it more prone to disease occurrence. Overall, this study reveals the potential role of rhizosphere microbial communities in the formation of leaf blight resistance in P. salicina, providing theoretical support for the screening of antagonistic microbes and the development of microbe-based disease control strategies in plum orchards.

【Objective】Sweet cherry (Prunus avium L.) is highly valued for its bright coloration, crisp texture and pleasant sweetness; however, its high metabolic activity and fragile skin make the fruit extremely vulnerable to postharvest deterioration, particularly under cold storage, where weight loss, textural decline and color fading frequently occur. In recent years, melatonin (MT) has been reported to participate in plant stress mitigation and postharvest physiological regulation, yet the effects of preharvest application on cold-stored sweet cherries remain insufficiently defined, especially regarding cultivar-dependent responses. Therefore, this study aimed to evaluate the influence of different MT concentrations applied at various developmental stages on fruit physicochemical quality during refrigerated storage, and to provide theoretical guidance for the precise application of melatonin in sweet cherry production.【Methods】Two commercial sweet cherry cultivars, Luying 3 and Luying 5, grown under identical orchard conditions, were subjected to foliar sprays of exogenous MT at the hard-core stage（25 days after full bloom, DAFB）, the color-break stage (45 DAFB) , and three days before harvest (55 DAFB) . Multiple MT concentrations were compared. After harvest, the fruits were stored at 4℃ under controlled relative humidity. At 0, 7 and 14 days of storage, weight loss, total soluble solids (TSS) content, texture profile analysis (TPA) parameters (including hardness, springiness, cohesiveness, gumminess and chewiness) , and color metrics (L*, a*, b*) were evaluated according to standard postharvest testing protocols. Multivariate analyses, including principal component analysis (PCA) and a correlation heatmap, were used to elucidate relationships among measured variables and to comprehensively discriminate the storage performance of different treatments. Statistical differences were tested at P≤0.05.【Results】The application of MT demonstrated clear concentration-and cultivar-dependent effects. During cold storage, weight loss increased significantly with storage time in both sweet cherry cultivars, with consistently higher values observed in Luying 5 than in Luying 3. High melatonin concentrations (0.30 mmol · L-1) significantly exacerbated weight loss at the late storage stage in both cultivars, whereas low to moderate concentrations partially alleviated weight loss at specific storage periods. Total soluble solids (TSS) content generally declined during storage; however, melatonin treatments differed in their ability to maintain TSS levels, with lower concentrations showing a relatively positive effect and higher concentrations accelerating TSS content depletion. In both cultivars, low-concentration MT (0.05-0.10 mmol · L-1) consistently preserved higher TSS content, implying a delayed reduction in fruit sweetness during cold storage. MT treatment also mitigated the decline of TPA hardness and maintained superior textural integrity, possibly by stabilizing cell wall structure or suppressing pectin solubilization. Colorimetric analyses revealed that MT inhibited undesirable increases in a* values and modulated shifts in L* and b*, implying delayed pigment oxidation and improved external appearance. Notably, fruit redness in MT-treated groups developed more uniformly, and surface brightness remained relatively stable. The correlation heatmap indicated that hardness, TSS content and chromatic parameters were positively associated and were critical determinants of fruit sensory acceptability. PCA analysis further demonstrated that these indicators accounted for the majority of variance among treatments, effectively distinguishing MT-treated fruits from the control at later storage stages. Cultivar-dependent responses were evident: Luying 5 exhibited high sensitivity to MT, particularly in adhesion-related texture attributes and mass retention, whereas Luying 3 displayed comparatively milder responsiveness across most parameters. At 14 days of storage, fruits treated with lower MT concentrations generally maintained higher overall quality scores, whereas excessive concentrations induced variable and sometimes negative results. These findings highlight the importance of dosage optimization in preharvest regulation.【Conclusion】Preharvest foliar application of melatonin at appropriate concentrations can effectively delay postharvest quality deterioration in sweet cherry fruits during cold storage. MT contributes to the maintenance of fruit weight, the conservation of soluble solid levels, the retention of desirable texture properties and the stabilization of color attributes. However, responses differ considerably among cultivars, underscoring the necessity of tailoring treatment strategies to specific genotypic characteristics. Low MT concentrations (0.05-0.10 mmol · L-1) are generally recommended for enhancing sweetness, firmness and surface brightness, while excessive concentrations may induce adverse effects, particularly in cultivars with lower tolerance.

【Objective】As an important woody oil crop, macadamia relies heavily on harvest timing for optimal fruit quality. Currently, Yunnan, being China′s largest macadamia growing region (accounting for 80% of the national planting area) , lacks a scientifically based harvesting decision system, which severely limits the high-quality development of the industry. This study systematically investigated the dynamic changes in the appearance traits and fruit quality of the main macadamia (Macadamia spp.) varieties in Dehong Autonomous Prefecture, Yunnan province, across different harvesting periods in order to provide solution to the problem of unstable fruit quality due to improper harvesting time, thereby es tablishing scientific harvesting standards. This, in turn, will enhance the commercial value and processing quality of macadamia fruits, thereby contributing to the sustainable development of Yunnan's macadamia industry.【Methods】Three main cultivars: HAES344, Disi No.1, and Own Choice were selected as test materials for this study. The study was conducted at the Manhuan plantation in Yingjiang County, Dehong Autonomous Prefecture, characterized by a South Asian tropical monsoon climate. During the fruit maturation period (August 1 to October 6) , four equally spaced sampling time points were set. Nine healthy 13-year-old trees per variety, totaling 27 sample trees, were used. Fruit cluster samples were collected from four directions in the outer canopy. Appearance indicators such as endocarp color and glossiness were recorded, combining dissection methods with image recording. Fruit morphology parameters including fresh fruit mass, fresh nut mass, and dry mass were measured using an electronic balance with 0.01 g precision. Processing quality indicators such as shelling rate, kernel recovery, and first-grade kernel rate were calculated. Additionally, protein, starch and fat contents were determined. Differences among periods were compared using one-way ANOVA (LSD) ; Pearson correlation analysis was applied to reveal inter-indicator relationships, and key quality indicators were extracted through principal component analysis. Finally, a multi-dimensional comprehensive evaluation system was constructed using membership function analysis to establish a quantitative prediction model for the harvesting period.【Results】Delaying harvest resulted in gradual endocarp darkening, increased glossiness, and enhanced lignification in all the three varieties. Disi No.1 performed best, displaying deep brown color with bright glossiness at final stage, indicating superior marketability. HAES344 colored slowly, showing uneven deep brown at maturity, while Own Choice maintained lighter pigmentation, reaching only light brown. For processing quality, kernel recovery and grade-one kernel rate significantly increased with delayed harvesting. The kernel recovery of HAES344 increased from 28.35% to 33.67%;that of Disi No.1 from 32.19% to 41.86%, and that of Own Choice from 33.36% to 36.04%. The kernel recovery rate of Disi No.1 peaked at 41.86% during the late harvest period. Own Choice maintained a stable grade-one kernel rate of over 99% in later harvesting stages. Shell-out rate remained stable (variation≤3%) . Nutritionally, fat content was generally high but varied among varieties. The fat content of the three cultivars ranged from 67.90% to 77.82%, with coefficients of variation all below 6%. HAES344 and Own Choice showed an initial increase followed by stabilization, while Disi No.1 first rose, then slowly declined, and finally stabilized. Soluble sugar and protein peaked early then decreased and stabilized. Disi No.1 had the highest soluble sugar content that reached 150 g · kg-1 soluble sugar, and HAES344 had the highest protein content of 82 g · kg-1. Moisture content consistently decreased to 18%-20%. Correlation analysis showed fat content positively correlated with kernel recovery and gradeone kernel rates, but negatively correlated with protein, moisture content, and shell-out rate. Principal component analysis indicated the first component (52.0% contribution) reflected fat content and processing quality (HAES344 highest) . The second component (26.5% contribution) linked to soluble sugar and shell-out rate (Disi No.1 most prominent) . Own Choice showed balanced performance.【Conclusion】Based on membership function analysis, optimal harvesting periods differed significantly:HAES344 and Own Choice are best harvested in mid-September, while Disi No.1 should be harvested in early October. This finding fills a research gap for macadamia harvesting in Yunnan and provides a scientific basis for precise harvest scheduling. Future studies should incorporate meteorological factors to develop dynamic prediction models for optimizing harvest timing.

【Objective】The endosperm of angiosperms is a product of double fertilization, belonging to triploid tissue, containing genetic material from both parents, and differs from ordinary hybrids. It contains two copies of maternal genetic material and one copy of paternal genetic material. Due to the rapid development of biotechnology, triploid plants can be obtained through endosperm culture, and new nucellus-free germplasm can be acquired through hybridization, which holds significant breeding value for fruit trees that primarily rely on vegetative propagation. The study aimed to establish a complete technical system for endosperm culture of Actinidia arguta, and obtained polyploid plants.【Methods】In the early stage of the study, the callus induction screening experiments of different hormone ratios were carried out. It was found that the combination of 6-BA and NAA was more suitable for the callus induction culture of kiwifruit endosperm, and the callus induction rate was high and the differentiation of callus was promoted; Three kinds of artificially domesticated wild A. arguta and‘Longcheng No.2' with different reproductive stages were used as experimental materials to study the effects of different sampling times and culture media on the formation and differentiation of endosperm culture organs, and determine the best sampling period and culture medium formula; The differentiated plantlets were cultured in succession and subjected to flow cytometry for cell multiplication identification. Using the immature endosperm of A. arguta as explants, sampling was set when the immature endosperm began to form, and samples were taken every 10 days for a total of four times. The samples were inoculated onto callus induction medium, and the callus induction status was surveyed every 10 days. Subsequently, the endosperm callus was inoculated onto different differentiation media, and the callus differentiation status was regularly monitored to determine the optimal sampling time and the best endosperm callus induction and differentiation media.【Results】Starting from the formation of the endosperm, samples were collected every 10 days for stereomicroscopic observation of seed morphology. As the seeds matured, the seed coat color gradually transitioned from light brown to dark brown, while the endosperm texture evolved from loose and incompletely filled to firm, hard, and fully enclosed. The embryo grew larger with progressively hardened texture, becoming easier to separate from the endosperm. This study effectively minimized embryo interference. After inoculation, the callus induction and growth were observed and recorded every ten days. The endosperm was induced to form callus tissue. With the increase of culture time, the callus became compact and differentiated into plants. Subsequent studies explored synergistic effects of NAA and 6-BA at different concentrations. After 60-day callus induction, researchers compared growth patterns across hormone ratios and sampling intervals. Significant variations in optimal induction media were identified across cultivars during different growth phases. The optimal culture medium was 1/2MS with NAA at 0.05, while 6-BA concentrations varied significantly (0.5, 2.0, 1.0 and 1.0) . Under identical cultivation conditions, optimal sampling times varied significantly depending on maturity stages. Material TH1, TH2, TH3 and Longcheng No.2 showed optimal sampling at 60-70 days, 70-80 days, 65 days and 70-80 days post-flowering, respectively. Through observing callus differentiation under different media, we found that mediumⅠandⅡstrains simultaneously differentiated roots and shoots, with Ⅱ ＞ Ⅰ in shoot differentiation. The root systems of medium Ⅲstrains showed no bud differentiation, though overall differentiation numbers were relatively low. As cultivation time extended, browning became more pronounced, ultimately yielding unsatisfactory results. Flow cytometry analysis confirmed all differentiated seedlings were octaploid, validating this conclusion. Literature reviews indicate that transferring callus tissue to MS+1.0 mg · L-1 2, 4-D+3.0 mg · L-1 Zt medium not only increased genetic variation but also significantly boosted plant differentiation, providing a basis for subsequent experiments. The results of the diploid detection by flow cytometer showed that the parental material of TH1, TH2, TH3 and their common parent material, and the parental material of Longcheng No.2 were all tetraploid. Using regenerated plants as controls and TH1 embryo tissue culture buds as reference for relative DNA content, the results showed that the regenerated plants were hexaploid, octoploid and octoploid (rather large) . Physiological measurements revealed polyploid plants exhibited significantly longer leaves, wider leaf margins, larger stomatal openings, and reduced stomatal density compared to tetraploid plants, demonstrating better environmental adaptability.【Conclusion】Few studies have been conducted on the endosperm culture from A. arguta. This paper investigated the cultivation of endosperm from different reproductive stages of artificially domesticated wild A. arguta varieties. By regularly comparing the induction and differentiation of callus, it aimed to determine the optimal sampling time, endosperm callus induction medium, and differentiation medium. Through flow cytometry for ploidy identification, multiple polyploid plants were differentiated. The study found that the reproductive stage significantly affected the sampling time and tissue culture conditions. The reproductive stage discussed in this paper was incomplete, and future research can improve the endosperm tissue culture system by adding more varieties at various reproductive stages. Additionally, by investigating the traits of the offspring with different ploidy levels, superior varieties can be selected for breeding studies.

【Objective】Kiwifruit (Actinidia spp.) is a globally important economic fruit crop with a diverse genetic background. Actinidia rufa is characterized by strong resistance to biotic and abiotic stresses, particularly environmental adaptability, whereas Actinidia chinensis is widely cultivated for its large fruit size, excellent flavor, and high commercial value. Interspecific hybridization between these two distantly related species represents a critical pathway for breeding novel cultivars that combine stress re sistance with superior fruit quality“ ( wide crossing”) . However, due to the complexity of the Actinidia genome and potential reproductive barriers in distant hybridization, the genetic architecture, inheritance patterns, and parental contribution in their F1 progeny remain largely unclear. Understanding whether the offspring genetically incline towards the maternal or paternal parent is crucial for designing subsequent breeding strategies, such as backcrossing schemes. This study aims to evaluate the genetic diversity, population structure, and authenticity of 202 F1 individuals derived from a cross between A. rufa (female) and A. chinensis (male) using Simple Sequence Repeat (SSR) markers. The specific goals are to validate the efficiency of SSRs for hybrid identification, quantify the level of genetic differentiation between parents, and elucidate the phenomenon of genetic segregation distortion or parental bias in the hybrid population.【Methods】A total of 202 F1 individuals and their parents were used as experimental materials. Genomic DNA was extracted from young leaves. A rigorous screening process was conducted to select 40 pairs of highly polymorphic SSR primers from a larger pool of candidate markers. These primers were used for PCR amplification, and the products were detected using high-resolution capillary electrophoresis to ensure accurate allele sizing. Genetic diversity parameters, including the Number of Alleles (Na) , Effective Number of Alleles (Ne) , Observed Heterozygosity (Ho) , Expected Heterozygosity (He) , Shannons Information Index (I) , and Polymorphism Information Content (PIC) , were calculated to assess the variability within the population. Analysis of Molecular Variance (AMOVA) was performed to partition the genetic variance among and within populations, and the genetic differentiation coefficient (Φst) was calculated to quantify the divergence between the parental species. To visualize the genetic structure and relationships, Principal Component Analysis (PCA) and UPGMA (Unweighted Pair Group Method with Arithmetic Mean) cluster analysis were conducted. Furthermore, the Hybrid Index (h) was calculated for each individual to quantify the genomic contribution of each parent, ranging from 0 to 1. Finally, a subset of 8 pairs of specific, complementary SSR primers was selected to identify true hybrids and construct DNA fingerprints for the population.【Results】The molecular analysis revealed that the 40 selected SSR primers were highly informative, detecting a wealth of genetic variation within the population with an average Polymorphism Information Content (PIC) of 0.631. The F1 population exhibited a high level of genetic diversity, characterized by a mean Expected Heterozygosity (He) of 0.741 and a Shannon's Information Index (I) of 1.36. A significant finding was the phenomenon of"Heterozygote Excess", where the Observed Heterozygosity (Ho=0.813) was significantly higher than the Expected Heterozygosity (He=0.741, P＜0.01) , suggesting that the interspecific hybridization effectively broke the linkage drag or inbreeding depression often found in intraspecific crosses. AMOVA results indicated that 32.74% of the total genetic variation occurred among populations, with a genetic differentiation coefficient (Φst) of 0.327, confirming that A. rufa and A. chinensis are genetically distinct species with significant allelic divergence. Crucially, the analysis of genetic structure revealed a striking pattern of paternal bias. The Hybrid Index (h≈0.35) , together with PCA and cluster analyses, consistently revealed a significant paternal bias (toward A. chinensis) in the genetic structure of the F1 generation—a pattern markedly different from the maternal bias commonly observed in species such as tea plants. This phenomenon was distinct from the maternal inheritance patterns that were often reported in other woody plants. Additionally, using the 8 specific SSR primer pairs, the study successfully distinguished true hybrids from potential selfs or outcrosses, with a true hybrid rate between 93.07% and 98.02%. DNA fingerprints containing parent-specific loci were constructed for the authenticated hybrids.【Conclusion】This study successfully demonstrates the utility of SSR markers for the rapid and accurate identification of interspecific hybrids in Actinidia. The F1 population derived from A. rufa × A.chinensis is characterized by high genetic diversity and significant heterozygote excess, providing abundant variation for breeding selection. Most notably, the study reveals a strong paternal genetic tendency (bias towards A. chinensis) in the F1 generation. This finding implies that while the hybrids successfully inherit the desired quality traits from the paternal A. chinensis, there is a risk of losing the resistance traits from the maternal A. rufa due to segregation distortion. Therefore, this study provides a critical molecular theoretical basis for future breeding strategies: to combine high quality with high resistance, larger population sizes may be needed to find the rare individuals with balanced inheritance, or specific backcross strategies to the maternal parent may be required to recover the resistance genes. The constructed DNA fingerprints will serve as a permanent record for germplasm protection and management.

【Objective】As the largest producer and consumer of citrus in the world, China's citrus industry has undergone significant shifts in its spatial patterns in recent years under the influence of climate change, primarily reflected in the relocation and concentration of production areas. Investigating the key climatic factors driving the spatial evolution of citrus production is of great significance for optimizing industrial layout and ensuring sustainable development. This study aims to systematically analyze the spatial evolution of China's citrus industry from 2002 to 2022, identify the main climatic drivers of its spatial changes, and provide a scientific basis for policy formulation and industrial planning.【Methods】This study takes 19 major citrus-producing provinces (regions) in China as the research subjects and utilizes panel data from 2002 to 2022. By integrating spatial econometric models and statistical analysis methods, it systematically explores the spatial agglomeration patterns of citrus production and its influencing factors. Specific methods include: first, using the global Moran's I to evaluate the spatial clustering characteristics of citrus production and revealing the positive correlation and temporal trends in its spatial distribution. The spatial correlation of citrus production in China is analyzed through the global Moran's I, while local Moran's I (LISA) is applied to identify high-high clusters and low-low clusters, further revealing spatial heterogeneity among regions. Second, a two-way fixed effects model is constructed to quantify the effects of climatic factors (annual average temperature, precipitation, frost days, hail days, average maximum temperature, and relative humidity) on the spatial distribution of citrus production. Through model fitting, the contribution of each factor to the spatial evolution of citrus production is determined, and regional differences are analyzed. Key climatic variables focus on annual average temperature and precipitation, exploring their impact on the spatial distribution of citrus yield. By classifying precipitation years into wet, normal, and dry years, the relationship between citrus production spatial distribution and precipitation is clarified. Based on these results, ArcMap 10.8.1 and Origin 2024 software are used to visualize the spatial distribution characteristics of different main producing areas and examine regional differences in climatic conditions, providing a basis for formulating regionally differentiated policies.【Results】 (1) The spatial distribution of citrus production in China exhibited a three-stage evolutionary characteristic:“random dispersion-strengthened agglomeration-high stability.”From 2002 to 2004, the distribution was random (Moran's I fluctuated between-0.009 5 and 0.012 3, P＞0.1) . From 2005 to 2015, the agglomeration effect continuously strengthened (Moran's I peaked at 0.0826, with P＜0.05 after 2007) . From 2016 to 2022, it entered a highly stable state (Moran's I fluctuated between 0.055 and 0.079, showing a significant positive correlation) . (2) The distribution of citrus-producing areas showed a clear trend of“shifting to southward and expanding to westward.”Throughout the study period, high-high clusters remained anchored in the South China region at the junction of Guangdong, Guangxi, Hunan, and Jiangxi, while low-low clusters were consistently distributed in high-altitude areas of the north, northwest, and southwest. The GannanXiangnan-Northern Guangxi citrus belt and the citrus belt in the middle and upper reaches of the Yangtze River have become the core production areas, accounting for 61.5% of total production in 2022. (3) The influence of climatic factors on changes in citrus production areas exhibited regional heterogeneity. The annual average temperature (Te) coefficient was 0.929, showing a significantly positive effect at the 10% level. In contrast, the average maximum temperature (Tmax) coefficient was-0.724, indicating a negative trend. Precipitation (Ra) had a coefficient of 0.310, which was significantly positive at the 5% level. The coefficient for hail days (Ha) was-0.193, reflecting a significant negative impact on citrus production layout. The coefficients for relative humidity (Hm) and frost days (Fr) were-0.141 and 0.063, respectively, and were not statistically significant. Regionally, the citrus belt in the upper and middle reaches of the Yangtze River was influenced by annual average temperature, average maximum temperature, relative humidity, and frost days (P＜0.05) . The southern Jiangxi-southern Hunan-northern Guangxi citrus belt was primarily affected by annual average temperature, relative humidity, hail days, and frost days. The western Hubei-western Hunan citrus belt showed a significant response to hail days (P＜0.1) . The characteristic citrus production zone was affected by the average maximum temperature and the number of frost days (P＜0.1) , which was close to the significant level. (4) The effects of different precipitation years on yield varied significantly across regions. Overall, production performed best in normal precipitation years. The Gannan-Xiangnan-Northern Guangxi citrus belt was prone to waterlogging risks in wet years, while the Western Hubei-Western Hunan citrus belt exhibited strong drought resistance in dry years.【Conclusion】This study systematically reveals the spatial evolution of citrus production in China and its climatic influencing factors under climate change. Based on the findings, the following recommendations are proposed: In the Gannan-Xiangnan-Northern Guangxi citrus belt, we should focus on waterlogging prevention and optimizing drainage systems; in specialized citrus production zones, water conservancy infrastructure should be strengthened and rainwater-harvesting agriculture should be developed; in the citrus belt in the middle and upper reaches of the Yangtze River, the water-saving irrigation needs to be improved; in the Western Hubei-Western Hunan citrus belt, the dry farming techniques can be promoted; in the Zhejiang-Fujian-Guangdong citrus belt, its current model should be maintained while emphasizing quality improvement.

【Objective】The Yuelu melon is a premium melon variety. After being introduced and cultivated in limited quantities in Hainan, Fujian, and Guangdong provinces, it has demonstrated significant economic value. In 2025, a Fusarium fruit rot disease affecting Yuelu melon was discovered in Guangzhou, with an incidence rate ranging from 5% to 8%. The disease altered the aroma, flavor, and quality of the melon, thereby diminishing its nutritional and commercial value. During cultivation, symptoms were observed exclusively within the fruit, with no visible external manifestations, which significantly increased the challenges associated with disease detection and management. The study aimed to identi fy the pathogen and elucidate its suitable growth conditions, including temperature, pH, light, as well as carbon and nitrogen sources. In addition, the toxicity of various fungicides to the pathogen was evaluated to assess their efficacy, thereby providing insights for effective disease control.【Methods】From April to June 2025, a survey was conducted to assess the incidence and severity of fruit rot in Yuelu melon at the Xiangfeng Special Fruit Industrial Park in Zengcheng District, Guangzhou City. Field symptoms were documented photographically. Diseased tissue samples were collected and, following surface disinfection, they were cultured on potato dextrose agar (PDA) at 26℃ for 3 days using the tissue isolation method. Mycelia from the margins of developing colonies were then transferred to PDA plates. Purified strains were obtained through single-spore isolation and stored at 4℃for subsequent use. Pathogenicity was confirmed through two inoculation methods. The first involved mycelia inoculation: The mycelia surfaces of the tested strains were adhered to the puncture site of the melon fruits, with blank agar discs used as controls. The second method employed spore suspension inoculation: 100 µL of spore suspension (5 × 106 spores · mL-1) was injected into the fruit from the tail end. All treated fruits were incubated at 26℃. Once softening or clear symptoms developed, the pathogens were isolated and purified again for verification in accordance with Koch's postulates. The strains were inoculated on potato dextrose agar (PDA) , synthetic nutrient-poor agar (SNA) , and carnation leaf agar (CLA) in the dark at 26℃for 10 days. Mycelia, conidiophores, conidia attachment patterns, conidia and chlamydospores were observed under an optical microscope, and the size of conidiophores and conidia were measured (n=80) . Genomic DNA was extracted from the tested strains, and the calmodulin (CAM) , translation elongation factor 1-alpha (EF1-α) , and the second largest subunit of RNA polymeraseⅡ (RPB2) gene regions were amplified via PCR. The products were sequenced by Shanghai Sangon Biotech Co., Ltd. The resulting sequences were submitted to the NCBI database to obtain accession numbers. Concurrently, BLAST analyses were performed on NCBI to identify and retrieve sequences of closely related species from GenBank. Sequence alignment was conducted using Mega 7.0 software, followed by manual splicing of the aligned datasets. A phylogenetic tree was constructed using the concatenated sequences of CAM, EF1-α, and RPB2 through the neighbor-joining method implemented in MEGA 7.0 to confirm species identification. Furthermore, the tested strains were cultured in an incubator under varying growth conditions, including temperature, pH, light intensity, carbon sources, and nitrogen sources, to determine the optimal culture environment for mycelia growth and spore production. Subsequently, to evaluate the sensitivity of the pathogen to various fungicides, eight commercial fungicides were tested. Mycelia discs were inoculated onto potato dextrose agar (PDA) plates supplemented with each fungicide at designated concentrations and incubated at 26℃. Colony diameters were measured after 5 days of incubation.【Results】The external appearance of diseased fruits showed no visible symptoms in the field. However, their tail ends felt soft to the press, and internal examination revealed brown, watersoaked rot, occasionally accompanied by a thin layer of white mold on the diseased areas. A total of 27 Fusarium spp. isolates with similar morphological characteristics were obtained. Pathogenicity tests revealed that artificial inoculation with strains YLG-4, YLG-13, and YLG-21 produced symptoms consistent with those observed under field conditions. On PDA medium, the colonies were initially white and later turned light yellow with cotton-like and abundant aerial mycelia. Conidiogenous cells were phialidic, 2.72 to 49.69 µm (n=80) on SNA medium and 3.63 to 52.65 µm (n=80) on CLA medium. Macroconidia were falcate, slightly curved, tapering apically with 1 to 5 septa, (17.45-46.78) µm× (2.62-4.93) µm (n=80) on SNA medium, (15.84-44.27) µm× (2.71-4.95) µm (n=80) on CLA medium, borne false heads from monophialides and polyphialides. Chlamydospores were spherical on both media. The CAM, EF1-α, and RPB2 gene fragments of strains YLG-4, YLG-13, and YLG-21 were amplified and sequenced, producing fragments approximately 550 bp, 840 bp, and 600 bp in length, respectively. BLAST analysis against the GenBank database showed that the nucleotide sequences of the CAM, EF1-α and RPB2 regions from these strains shared 99.29% to 100% identity with corresponding sequences of Fusarium pernambucanum strains CBS 791.70, CBS 132194, CBS 132894, and CBS 133024. A phylogenetic tree was constructed based on the concatenated sequences of CAM, EF1-α, and RPB2 using the neighborjoining method, which demonstrated that YLG-4, YLG-13, and YLG-21 form a cluster with F. pernambucanum. Integrating morphological characteristics and molecular evidence, strains YLG-4, YLG-13, and YLG-21 were identified as F. pernambucanum. The optimal temperature range for mycelia growth of strain YLG-13 was 24-30℃, with the most rapid colony expansion observed at 26-28℃and the highest conidia production occurring at 30℃. Mycelia growth was favorable within a pH range of 5-10, with an optimum at pH 7-9. Light promoted mycelia development. Carbon sources such as glucose and soluble starch, as well as organic nitrogen sources including tryptone, beef extract powder, and yeast extract, were found to enhance both mycelia growth and spore production in YLG-13. Among the eight fungicides tested, all exhibited varying degrees of inhibition on mycelia growth. Fludioxonil showed the strongest inhibitory effect, with an EC50 value of 0.014 7 mg · L-1, followed by prochloraz, which had an EC50 value of 0.637 3 mg · L-1.【Conclusion】In this study, the causal agent of fruit rot in Yuelu melon was identified as Fusarium pernambucanum through pathogenicity tests, morphological characterization, and multi-locus phylogenetic analysis based on the CAM, EF1-α, and RPB2 gene regions. The pathogen showed adaptation to relatively high temperatures and neutral to alkaline conditions. Fungicide assays revealed that fludioxonil and prochloraz exhibited the strongest antifungal activity, suggesting their potential as effective agents for disease control. These findings offer a theoretical foundation for diagnosing and managing this disease.

【Objective】Grapevine (Vitis vinifera L.) is one of the most economically important fruit crops globally, valued for its use in fresh consumption, winemaking, and processed products. However, its productivity and quality are severely threatened by grape white rot, a devastating fungal disease caused by Coniella diplodiella (Speg.) Sacc (C. diplodiella) . This pathogen primarily infects berries, leaves, and shoots, leading to fruit rot rates exceeding 50% in severe outbreaks and significant economic losses. Current management strategies rely heavily on chemical fungicides, which pose risks of environmental pollution, pathogen resistance, and food safety concerns. Thus, identifying host resistance genes and elucidating their molecular mechanisms is critical for developing sustainable disease management strategies through molecular breeding. Plant transcription factors (TFs) play pivotal roles in regulating immune responses by orchestrating the expression of defense-related genes. The WRKY family, characterized by the conserved WRKYGQ motif and zinc finger domains, is well-documented for its involvement in biotic stress responses, but their functions in grape white rot remain poorly understood. Here, we cloned and characterized VvWRKY5 (GSVIVT01019419001) , a WRKY TF gene from the grape cultivar Red Globe, to investigate its role in white rot resistance and underlying regulatory mechanisms.【Methods】A phylogenetic tree was constructed using MEGA7.0 with the neighbor-joining method (1000 bootstrap replicates) , including VvWRKY5 and WRKY proteins from Arabidopsis, Oryza sativa, and Malus domestica. For subcellular localization, the coding sequence (CDS) of VvWRKY5 was fused to GFP in the pRI101 vector and transiently expressed in onion epidermal cells via Agrobacterium tumefaciens-mediated transformation. Fluorescence was observed using a confocal laser scanning microscope. To identify the potential roles of VvWRKY5 in resistance to white rot, Agrobacterium tumefaciens carrying recombinant plasmids (VvWRKY5-pRI and VvWRKY5-TRV2) were infiltrated into Red Globe leaves and Red Gamay grape callus, respectively, and their resistance was subsequently evaluated following inoculating the C. diplodiella. Subsequently, we observed the phenotypes of VvWRKY5transgenic and non-transgenic materials after inoculation with the white rot pathogen, measured stressrelated physiological parameters (including O2- and MDA contents, etc.) , and analyzed the expression levels of the key stress response genes VvNPR1 (nonexpressor of pathogenesis-related genes 1, a core gene in the salicylic acid signal transduction pathway) and VvPR1 (encoding pathogenesis-related protein 1) using qRT-PCR technology. A yeast one-hybrid was performed to validate the interaction between VvWRKY5 and VvNPR1 promoter by observing the growth status of the yeast cells cotransformed with VvWRKY5-pGADT7 and ProVvNPR1-pHIS2 on the SD/-Trp/-His/-Leu defined medium supplemented with the 3-amino-1, 2, 4-triazole (3-AT) . In addition, the effect of VvWRKY5 on VvN-PR1 transcriptional activity was studied using the luciferase reporter assay. The coding region sequence of VvWRKY5 was inserted into the pRI101-AN vector and the promoter fragment of VvNPR1 was introduced into pGreenII 0800-LUC vector. One-month-old tobacco (N. benthamiana) leaves were infected with Agrobacterium tumefaciens strain GV3101 carrying the recombinant plasmids. After the plants were kept in the dark for 48 h, luciferase activity was detected using the live imaging analysis system.【Results】Sequence analysis indicated that the open reading frame of VvWRKY5 was 972 bp, which encoded 323 amino acids. The predicted molecular weight of the protein was 35.70 kD, the theoretical pI was 5.85, and the protein contained a WRKY conserved domain and a C2H2 zinc finger domain. Phylogenetic analysis showed VvWRKY5 shared 78% amino acid identity with AtWRKY22 from Arabidopsis thaliana, indicating a close evolutionary relationship. qRT-PCR results showed that VvWRKY5 expression was highly induced after C. diplodiella inoculation and was ubiquitously expressed in all tissues, with the highest expression levels in leaves (3.0-fold higher than roots) and fruits (2.7-fold higher than roots) . Subcellular localization assays confirmed that VvWRKY5-GFP fluorescence was exclusively localized to the nucleus, consistent with its role as a TF. Functional analysis indicated that the lesion area of grape leaves and callus overexpressing VvWRKY5 was significantly smaller than that of the control, the disease severity was reduced, and it could promote the expression of key disease resistance genes VvNPR1 and VvPR1. On the contrary, the lesion area of grape leaves with VvWRKY5 silenced was significantly larger than the control, the disease severity was significantly higher and the expression levels of VvNPR1 and VvPR1 were lower than the control. Yeast one-hybrid assay demonstrated that VvWRKY5 directly bound to the VvNPR1 promoter containing a W-box motif (-270 bp) , as yeast cells co-transformed with bait (ProVvNPR1-pHIS2) and prey (VvWRKY5-pGADT7) plasmids grew well on selective medium. Furthermore, the luciferase reporter assay revealed that VvWRKY5 could promote the transcriptional activity of VvNPR1, as the fluorescence signal in the tobacco leaves co-injected with 35S::VvWRKY5 and ProVvNPR1-LUC (35S::VvWRKY5+ProVvNPR1-LUC) was significantly stronger than the control groups (35S+LUC, 35S::VvWRKY5+LUC, 35S+ProVvNPR1-LUC) .【Conclusion】In conclusion, VvWRKY5 is a typical WRKY transcription factor associated with resistance to white rot in grape, which is significantly upregulated under C. diplodiella induction, and its overexpression positively regulates the resistance of grape to C. diplodiella. Moreover, its nuclear localization and tissue-specific expression (highest in leaves/fruits) align with its role in defending against foliar and fruit pathogens. Additionally, this study reveals a novel mechanism by which VvWRKY5 enhances grape resistance to white rot through activation of VvNPR1 transcription. This expands our understanding of WRKY-mediated immunity in grape and provides a candidate gene for breeding disease-resistant cultivars.

【Objective】The effects of different pollination methods on the fruit set rate, fruit quality, endogenous hormone levels, and economic costs of the self-fertile sweet cherry cultivar 7-2-9 under greenhouse cultivation were investigated. Based on this premise, multiple pollination treatments, including manual pollination using a feather duster, plant growth regulator application, bee pollination, and a nonassisted control, were established to comparatively analyze the physiological and developmental responses during fruit set and growth. The study focused on evaluating differences in fruit set stability, fruit size, soluble solid content, coloration traits, and the dynamic changes of endogenous hormones such as auxins, cytokinins, and gibberellins under different pollination conditions. In addition, a comprehensive assessment of labor input, operational costs, and overall economic efficiency associated with each pollination strategy was conducted to reflect their practical applicability in greenhouse production systems. The results further revealed both commonalities and differences among treatments in terms of improving fertilization efficiency, regulating fruit developmental synchronization, and enhancing fruit commercial quality. This work provides a scientific and technical basis for optimizing pollination management strategies under protected sweet cherry cultivation and supports the large-scale promotion of self-fertile cultivars in controlled environments.【Methods】The 8-year-old self-fertile sweet cherry cultivar 7-2-9 (Prunus avium L.) , grafted on Jingchun 2, was selected as the experimental material at the Tongzhou Cherry Base of the Forestry and Fruit Research Institute, Beijing Academy of Agriculture and Forestry Sciences. The experiment was conducted in a solar greenhouse under controlled environmental conditions (15-22℃, 50%-70% RH) , where four pollination treatments were established: natural selfpollination (CK) , hand pollination (HP) with feather dusters, plant growth regulator treatment (PGRT) involving a multi-component solution including GA3, 6-BA, and NAA, and bee pollination (BP) using Apis mellifera ligustica. To ensure experimental precision, isolating nets were employed for CK, HP, and PGRT until fruit set was stable. The self-fertility of 7-2-9 was first validated through pollen germination assays and scanning electron microscopy (SEM, Hitachi SU-8010) to assess pollen morphology and uniformity. During the reproductive stages, the fruit set rate was calculated by monitoring flower and fruit counts on representative primary branches. Upon fruit maturity, physical quality traits (weight, shape index, and firmness) were measured using analytical balances, calipers, and the Firmtech FT-7 tester, while nutritional components (anthocyanins, VC, total phenols, and flavonoids) were quantified via colorimetric and enzymatic assays. Furthermore, endogenous hormone levels (IAA, CTKs, GA, SA, and JA) were determined using an LC-MS/MS system (ExionLCTM AD UPLC coupled with QTRAP® 6500+) , with samples stored at-80℃. Additionally, a standardized cost-benefit model was constructed to calculate pollination time, labor expenses (20 RMB/h) , and material inputs per 666.7 m2. Finally, all data were processed using SPSS 22.0 for one-way ANOVA and LSD tests, with graphical visualizations generated using GraphPad Prism 8.0.2.【Results】Significant differences were observed in the growth, development, fruit quality, and economic costs of greenhouse-cultivated 7-2-9 sweet cherries under different pollination treatments. Pollen assays and two-year field identification confirmed that 7-2-9 was a self-fertile cultivar with high pollen viability and a stable self-pollination fruit set rate (46.00%-58.00%) . Compared with the control, both hand pollination (HP) and plant growth regulator treatment (PGRT) significantly increased the fruit set rate, whereas bee pollination (BP) showed a limited promoting effect. Morphologically, PGRT induced pedicel elongation and inhibited endocarp development, resulting in seedless fruits with smaller endocarps, whereas HP and BP maintained fruit traits similar to those of the control. Regarding internal quality, PGRT optimized the sugar-acid ratio by reducing acidity, whereas HP significantly enhanced nutritional quality, producing the highest concentrations of anthocyanins (0.68 mg · g-1) and ascorbic acid (0.34 mg · g-1) . Physiological analysis revealed that PGRT and BP decreased IAA and tZ levels, whereas PGRT significantly increased the concentrations of cytokinins (BAP) , gibberellins GA1 and GA3, and JA. Finally, economic evaluation showed that PGRT incurred the highest total cost because of intensive labor and chemical inputs, followed by BP due to hive expenses. Overall, hand pollination (HP) was the most efficient strategy, significantly improving fruit set and nutritional quality with relatively low economic costs, thereby providing a balanced approach for highquality production under protected cultivation.【Conclusion】Different pollination methods had significant effects on the fruit set rate, fruit quality, and economic costs of the self-fertile sweet cherry 7-2-9 under protected cultivation. Both hand pollination (HP) and plant growth regulator treatment (PGRT) significantly improved the fruit set rate compared with the control. However, although PGRT promoted fruit set, it altered fruit morphology and endogenous hormone balance, and was associated with high labor intensity and production costs. Bee pollination (BP) maintained fruit quality but involved relatively high hive expenses with limited improvement in fruit set. In contrast, hand pollination (HP) not only effectively increased the fruit set rate but also minimized adverse effects on fruit quality, showing the highest economic feasibility. Therefore, hand pollination is recommended as the primary pollination strategy for self-fertile sweet cherries under greenhouse conditions. This study clarifies the trade-offs among different pollination methods and provides a technical basis for efficient production. Further research is needed to explore the molecular mechanisms by which different pollination stimuli regulate endogenous hormone metabolism during fruit development.

Citrus, belonging to the Rutaceae, is the most extensively cultivated and highest-yielding fruit crop in China, leading the world in both planting area and production. However, Citrus Huanglongbing (HLB) , a devastating bacterial disease caused by Candidatus Liberibacter spp., poses a severe global threat to the citrus industry. HLB causes tree decline, stunted growth, and symptoms including leaf yellowing and mottling, as well as small, misshapen, and unevenly colored fruits. Infected young trees typically die within 2-3 years, while mature trees succumb within 5-8 years. The primary insect vector of this disease, the Asian citrus psyllid (ACP) , Diaphorina citri, is native to Asia but has now spread to major citrus-producing regions worldwide, including the Americas and Africa. Currently, 13 provinces in China have found this pest. Influenced by factors such as warmer and more humid winter conditions, the psyllid is exhibiting a northward migration trend, with its suitable habitat continuously expanding. This significantly increases the risk of further HLB spread within China. As there is currently no effective cure for HLB, controlling its insect vector, the Asian citrus psyllid, has become the most critical strategy for disease management. This review systematically summarizes recent advances in various control strategies against the Asian citrus psyllid, focusing on four main aspects: (1) Agricultural control, centering on integrated orchard management. This involves scientific orchard planning, intercropping, and the rational use of adjuvants like mineral oils to create field environments unfavorable for psyllid establishment and dispersal; (2) Chemical control, which remains predominant challenges of insecticide resistance. Commonly used insecticides primarily belong to six major classes, including neonicotinoids and pyrethroids. However, prolonged and repetitive use of single modes of action has led to varying degrees of resistance in psyllid populations to many conventional insecticides. Therefore, imple menting science-based pesticide application practices is crucial. Key measures include targeted application, rotation of chemicals with different modes of action, rational use of adjuvants, and prioritizing highly effective, low-toxicity, and environmentally friendly agents to delay resistance development; (3) Biological control utilizing natural enemies and entomopathogens. Entomopathogenic fungi represent highly promising biocontrol agents. Researchers have found that Lecanicillium psalliotae ZJLP09 and Purpureocillium lilacinum GDIZM-2 exhibit considerable efficacy against the Asian citrus psyllid and hold potential for field application. Concurrently, the mass rearing and release of parasitoid wasps such as Tamarixia radiata and Diaphorencyrtus aligarhensis have achieved successful field control both domestically and internationally, serving as exemplary models of biological control. Predatory natural enemies, including ladybugs, lacewings, thrips, and spiders, also contribute effectively to suppressing adult psyllids and eggs; (4) Physical control methods, such as using insect-proof nets as barriers, and employing yellow sticky traps or light traps of specific wavelengths to monitor and mass-trap psyllids by exploiting their tropisms, effectively reducing pest population densities. Furthermore, the integration of unmanned aerial vehicle (UAV) -based remote sensing and sprayer technology is emerging as a new trend to enhance orchard monitoring efficiency and application precision. The article also explores the current status and potential of emerging molecular technologies like RNA interference (RNAi) and gene editing. Studies showed that the CsTPS21 gene encodes a jasmonic acid-responsive monoterpene synthase that produces β-ocimene in citrus, which exhibits significant repellent effects against the psyllid. Psyllid control can be enhanced through metabolic engineering to modulate CsTPS21 expression or via the direct application of β-ocimene. Additionally, developing plant-derived or synthetic high-efficacy attractants or repellents based on insect allelochemical mechanisms, integrated with a“push-pull”strategy to divert psyllids from citrus trees to trap plants for concentrated control, represents a highly promising green pest management direction. RNAi has become an important tool in insect functional genomics. Research has found that the Asian citrus psyllid is highly sensitive to double-stranded RNA (dsRNA) , and effective gene silencing can be achieved through oral delivery or topical contact. However, significant challenges remain for its practical field application. Issues such as the cost of dsRNA, its stability under field conditions, and the development of efficient delivery systems currently hinder the translation of RNAi technology from laboratory research to field implementation. In conclusion, every individual control method has its inherent limitations. Future management directions must inevitably evolve towards establishing an Integrated Pest Management (IPM) system grounded in ecological regulation and involving the synergistic application of multiple technologies. This review aims to systematically consolidate existing research findings, analyze current challenges, and outline future research priorities, thereby providing a theoretical foundation for the scientific management of the Asian citrus psyllid and for promoting the sustainable development of the citrus industry.