Abstract:Jiyu(original code:99-1-3)is a new late-ripening,cold-hardy pear cultivar developed by the Institute of Pomology,Jilin Academy of Agricultural Sciences.It was selected from hybrid population of a cross between Hanxiang(female parent)and Qiyuesu(male parent)made in 1999.212 viable seed-lings were obtained in 2000.The seedlings started fruiting in 2007.In 2012,99-1-3 was designated as a primary strain based on its superior fruit appearance and excellent internal quality.Accession 99-1-3 progressed to secondary selection in 2013,compared with the control cultivars Hanxiang,Jixiang,Pingxiang and Jinxiangshui.In 2015,expert validation confirmed its sustained trait stability and excep-tional cold hardiness.From 2018 to 2023,the regional trials across Jilin Province and ecologically anal-ogous zones confirmed consistent excellence in cold hardiness,broad adaptability,disease resistance,high yield potential and premium fruit quality.After DUS test,it received national cultivar registration(Certificate No.GPD Pear[2024]220005)from the Ministry of Agriculture and Rural Affairs,China in December 2024,and was officially released as Jiyu.This cultivar had a vigorous,upright-spreading hab-it,achieving heights of 5 m at maturity,with pronounced apical advantage and semi-erect scaffold branching.The color of 1-year-old shoots was reddish-brown with a mean internode length of 4.31 cm.The dormant leaf buds exhibited an obtuse-acute apex and were obliquely oriented along the shoot axis.The mature leaves were elliptic(10.08 cm length × 8.37 cm width),exhibiting dark green coloration,with truncate bases,acute apices,absent stipules and sharply serrated margins.The flowers were borne in corymbose inflorescences(7-8 florets per cluster),with pentamerous white petals and low pollen pro-duction.The fruits exhibited a globose conformation with an average single fruit mass of 153.0 g,dis-playing yellow ground color overlaid with a red blush on sun-exposed aspects.The flesh was white with minimal stone cell,a compact core and fine-textured crispness at harvest.Following postharvest ripen-ing for approximately 10 days at ambient temperature(20℃),the flesh became soft(flesh firmness:0.49 kg·cm-2).The fruits delivered a harmonious sweet-sour flavor with distinct weak aroma.The solu-ble solids content(SSC)was 15.30％,the soluble sugars content was 8.59％,and the titratable acidity was 0.33％.The fruit development required approximately 144 days from full bloom,reaching commer-cial maturity in late Septemberin Gongzhuling,Jilin(43.5° N,124.8° E).Under ambient storage,the fruits retained premium quality for 10-20 days until flesh firmness declines.This cultivar exhibited ex-ceptional cold-hardiness,validated through 20-year field observations encompassing multiple natural freezing events.It maintained undamaged growth in normal winters,with only minimal branch injury occurring during extreme frost episodes.This cultivar demonstrated significant resistance to pear leaf blotch,while exhibiting minor susceptibility to pear scab with little leaf incidence.It could be intro-duced for trial planting in the areas with frost free period over 135 days,effective accumulated tempera-ture(over 10℃)over 2800℃.The sandy soil or loam soil were preferred for cultivating this variety,with pH 6.0-7.5.Pyrus ussuriensis Maxim.should be suitable rootstock.The tree shape should be spin-dle form or multi-layered open-center canopy.The pear varieties Hansu,Hanhong and Pingxiang could be used as Pollinizers for it.

Abstract:Jibaleng is a newly selected Juglans hopeiensis Hu variety derived from the selection by seedling.The mother tree was discovered in 2002 on Fenghuang Mountain in Qianxi,Tangshan City.Its nuts are oblong with bold and twisted patterns,thick ribs,a flat base,a small umbilicus,eight prominent ridges converging at the top,and a star-shaped tip.From 2005 to 2010,systematic evaluation of botani-cal characteristics,growth and fruiting habits,and economic traits confirmed its phenotypic stability.In 2011,scions were collected for grafting in Laishui,Zanhuang,and Dingzhou.From 2021 to 2023,a sys-tematic study was conducted on the tree growth,fruit shape,yield potential,and stress resistance under different ecological conditions.DNA fingerprinting analysis was carried out using SSR markers to con-firm that there were differences among different cultivars.This variety was officially registered as Jiba-leng in 2024 by the Hebei Provincial Forest Variety Approval Committee(ID:Hebei S-SV-JH-012-2024).Jibaleng trees are tall and vigorous,with a height of 7.6 meters,a crown diameter of 6.5 m×6.8 m,and a new shoot growth of 68 cm in a 12-year-old tree.There are thick branches,abundant buds,strong branching ability,and a high fruiting branch rate in Jibaleng trees,and the average yield per tree is 221 walnut fruits.The bark is grayish green when young and turns grayish white with shallow longitudinal fissures when old.The leaves are odd-pinnate with 9-13 leaflets being elliptical,entire and smooth.Jibaleng is a typical protandrous variety.The male catkins are 12-19 cm long,and the female spikelets usually contain 1-3 flowers.The stigmas are light red.The fruiting spikes are short,with 1-3 fruits.The fruit is nearly round,with a longitudinal diameter of 5.37 cm,a transverse diameter of 5.18 cm,and a ridge diameter of 5.14 cm.The nut is oblong in shape,with a longitudinal diameter of 4.68 cm,a trans-verse diameter of 4.32 cm,and a ridge diameter of 4.36 cm.The suture lines are thick,and the patterns are rough and twisted like flowers.It has thick ribs,a large flat bottom,a small navel,eight ribs gath-ered at the top,and a cross-shaped tip.In Baoding,Hebei,the cultivar's budbreak occurs in the end of March to early April.The male flowers reach their peak in mid-April,and the female flowers reach their peak in mid to late April.The fruit growth period is from mid-May to late June,the fruit-core-hardening period is from late June to early July,the fruit ripening period is from mid-August to early September,and the leaves fall from late October to early November.This variety has the characteristics of high yield potential and high price,which is suitable for promotion in the suitable areas of walnut growing in Hebei.

Abstract:[Objective]Fire blight(Erwinia amylovora),a highly destructive bacterial disease,has posed a serious threat to the yield and quality of Kuerlexiangli pears.This study aims to explore the in-fluence patterns of external factors on the occurrence and development of fire blight in Kuerlexiangli pears,thereby providing an important theoretical basis for the comprehensive prevention and control of this disease.[Methods]An indoor simulation experiment was conducted to determine the disease inci-dence and disease index of detached leaves,branches,and young fruit after inoculation with E.amylovo-ra.The experiment was designed from six perspectives:1)infection routes(natural openings,friction wounds,incisions,and punctures);2)Different isolated organs:flowers,leaves,branches,and young fruits.3)leaf ages(3,7,15,30,and 40 d);4)temperatures(15℃,20℃,25℃,30℃,and 35℃);5)relative humidity(RH)(25％-35％,35％-45％,55％-65％,75％-85％,and 85％-100％);and 6)bacteri-al concentrations(OD600=0.4,0.8,1.0,1.2,and 1.6).Each treatment was set with three replicates,each including 30 flowers and leaves,10 branches,or 10 young fruit.After inoculation,the test materials were placed in trays lined with sterile gauze at the bottom;each tray was sealed with plastic film and then placed in an incubator with ambient temperature and humidity.The numbers of diseased leaves,branches,and young fruit were recorded at 24,48,72,96,120,144,and 168 h post-inoculation.Mean-while,the lesion diameter on leaves and young fruit,as well as the lesion length on branches,were mea-sured.Finally,the disease incidence and disease index were calculated using standard formulas.[Re-sults]The results showed that under the same environmental conditions,flowers and young fruit of Kuerlexiangli pears were more susceptible to E.amylovora infection than leaves and branches.For leaves,the younger leaf age,the faster the disease development:the 3-day-old leaves showed the fastest disease onset,while the 7-day-old leaves reached a disease incidence of 71.14％-100％at 72 h post-in-oculation.Compared with natural openings(stomata),mechanical wounds(friction wounds,incisions,and punctures)significantly increased the disease incidence,with the disease incidence of mechanically wounded leaves being 3.2-4.5 times higher than that of leaves infected through natural openings.When the temperature was between 25 and 30℃,the humidity between 75％and 85％,and the inoculation concentration was OD600=1.2,the incidence of pear blight bacteria was the highest.Moreover,as the concentration of the bacterial solution increased,the disease progressed more rapidly.[Conclusion]Among the organs of Kuerlexiangli pears,flowers are the most susceptible to fire blight,followed by young fruit,leaves,and branches.Infection routes,host organs,leaf age,temperature,humidity,and bac-terial concentration all exert effects on the lesion expansion of fire blight,and their interactions deter-mine the spread rate of the symptom in the host.In view of this,in the production of Kuerlexiangli pears,it is necessary to carry out prevention and control work in the early stages,especially during flow-ering and early fruiting stages,according to the changes in temperature and humidity.

Abstract:[Objective]As a recently domesticated fruit crop,the scientific research and commercial in-dustry of Actinidia arguta have developed rapidly both domestically and internationally.By 2024,the planting area in China had reached 6700 hectares.The wild resources of A.arguta are distributed in Northeast China,North China and the Yangtze River Basin,and are also distributed in Japan and the Far East of Russia.In order to assess the research status and industry development trend in this field,this pa-per analyzes the academic papers at home and abroad.[Methods]The bibliometric visualization soft-ware CiteSpace and VOSviewer were used to analyze the information about countries,institutions,au-thors,publications and research contents of A.arguta,taking the academic papers of A.arguta in the CNKI database from 1979 to 2024 and the Web of Science(WOS)database from 1966 to 2024 as the re-search materials.At the same time,the current status of A.arguta research at home and abroad is exam-ined,and the academic impact of this research is analyzed and evaluated.Understanding the current state of scientific research and industrial development of A.arguta is important for promoting its devel-opment and utilization,as well as the healthy growth of the industry.[Results]A total of 1283 papers were published during this period,of which 823 were in Chinese(64.15％)and 460 were in English(35.85％).The number of papers published each year showed an upward trend.The number of Chinese and English papers began to rise rapidly in 2010 and 2009,respectively,with the number of Chinese pa-pers exceeding that of English papers from 2011 to 2024.The study revealed that a total of 48 countries once published papers related to soft date A.arguta,with the top five countries in terms of the number of articles being China,Republic of Korea,Poland,New Zealand,and Japan,with 147,78,67,42,and 38 articles,respectively.The East Asian countries of China,the republic of Korea,and Japan accounted for 57.17％of the total number of articles of all the countries studied,demonstrating the East Asian re-gion is of worldwide research advantage.China is the most important country for studying A.arguta.The number of papers in the CNKI and WOS databases accounts for 75.60％of all Chinese and English literature.A total of 473 and 483 research institutions are included in the CNKI and WOS databases,re-spectively.The main institutions publishing in CNKI are Shenyang Agricultural University,the Institute of Special Animals and Plants of the Chinese Academy of Agricultural Sciences,and Yanbian Universi-ty,with 82,71,and 54 papers,respectively.All three of these institutions are located in the northeast re-gion.Of the top 20 institutions with the largest number of publications,16 are located in this region,in-dicating that it is the most important area for the study of A.arguta.From the perspective of the Web of Science(WOS),the top countries for A.arguta research are China,Poland,and Republic of Korea.A to-tal of 215 and 240 papers on A.arguta were published in the CNKI and WOS databases,respectively.The top five Chinese journals are Northern Horticulture,Liaoning Forestry Science and Technology,Forest By-products and Specialty in China,Special Wild Economic Animal and Plant Science,and Food Science,with 38,36,35,31 and 23 papers,respectively.The top five English journals were Scien-tia Horticulturae,Food Chemistry,Molecules,Frontiers in Plant Science and International Journal of Molecular Sciences,with 19,13,12,11 and 10 articles respectively.The authors of the research papers on A.arguta published in CNKI were ranked in order from highest to lowest:LIU Changjiang,QIN Hongyan,PIAO Yilong,AI Jun and FAN Shutian.The top 20 authors were based in the northeast Chi-na,10 of whom were affiliated with the Institute of Specialty Animal and Plant Sciences of Chinese Academy of Agricultural Sciences.Nine of the top 20 authors in the Web of Science(WOS)were from China,eight of whom were from the institution of Zhengzhou Fruit Research Institute,CAAS(China).The remaining foreign authors were mainly from the Warsaw University of Life Sciences(Poland),In-stituto Politecnico do Porto(Portugal)and the Korea Forest Research Institute(KFRI)(Republic of Ko-rea).The literature was analysed for its'burst words'.Except for'kiwifruit',the Chinese literature from CNKI only formed a hotspot for a period of time according to keywords such as'polysaccha-ride','total flavonoids','cultivation techniques','fruit'and'tissue culture'.The keywords that con-tinued into the recent period mainly included'phenotype'and'storage'.Except for'Antinidia delicio-sa',only keywords such as'expression','Hayward','quality','cultivars','fruit'and'cold stress'maintained a relatively high level of activity in chronological order in the WOS English literature,which also indicated the current focus of scientific research on A.arguta.In terms of the number of pub-lished papers and the average citation frequency,China has an absolute advantage in terms of research institutions,authors,and journals related to A.arguta.In terms of research content,China's focus is pri-marily on resource investigation,cultivar,tissue culture,cultivation technique,fruit quality and antioxi-dant activity.In contrast,foreign countries tend to study the antioxidant activity,expression,storage,cultivar and tissue culture of A.arguta.However,few studies have been conducted on the protection of A.arguta plants in China and abroad,and this area requires further strengthening.[Conclusion]China has a leading position in the research of A.arguta,mainly in the following areas:resources and breed-ing,cultivation techniques,fruit quality and function.The focus of international research is on such ar-eas as functionality,gene expression and storage performance.It is imperative that fundamental re-search must be reinforced in order to enhance the level of applied basic research and provide robust sup-port for industrial development.

Abstract:Pyrus ussuriensis'Fanhua',a new pear cultivar with excellent appearance,was selected from seedlings of natural hybridization of P.ussuriensis.From 2012 to 2015,a three-year comprehen-sive evaluation was conducted on the phenological phases,tree vigor,floral,foliar,shoot,and fruit char-acteristics of 52 natural seedlings of P.ussuriensis.Based on this evaluation,5 individuals with excel-lent comprehensive traits and suitability for ornamental planting were preliminarily selected in early 2015.From 2017 to 2019,a three-year consecutive comprehensive evaluation was conducted on one of the elite line Pu-AT-1.The cultivar has strong tree vigor,with a semi-upright canopy.The one-year-old shoots are yellow brown in color,with average length and diameter of 63.0 cm and 5.0 mm,respective-ly.The average length of internodes is 3.95 cm.The number of flowers per unit cross-sectional area of the pear tree trunk is 43.44 flowers/cm2.The average number of flowers per inflorescence is 6.8.The av-erage corolla diameter is 4.25 cm.The flower buds are deep pink with an average of five petals and overlapping each other in relative position.In the initial stage of petal expansion,the top of the petals is pink.As the flower gradually opens,it turns white.The petals are ovate.There are five stigmas,which outgrow the stamens.The base of the stigmas has no pubescence.The average number of stamens(an-thers)is 18.5,and they are deep purplish red.First bloom occurs very early.In Xingcheng area of Liaon-ing province,the first flowering occurs on April 8 and the full blooming on April 10,and the flowering period lasts 12 days,which is relatively long.This cultivar has strong cold resistance and is suitable for planting in cold regions such as Northeast China.It can be used for urban landscaping.It is suitable for cultivation in cold regions such as Northeast or Northwest China.This plant has a wide adaptation to soil conditions.Its roots can grow in acidic,neutral,or alkaline soils.To meet its basic growth require-ments,the planting sites should have abundant sunlight to facilitate full photosynthesis and a well-func-tioning drainage system to prevent waterlogging.In urban greening,plant spacing can be selected ac-cording to landscape requirements,3 m × 3 m or 3 m × 4 m.

Abstract:[Objective]Vitis davidii.is an important wild grape germplasm resource in southern China.The organic acids in its fruits primarily accumulate in the form of tartaric acid,malic acid and citric ac-id in the vacuoles during the early stages of fruit development,a process primarily influenced by alumi-num-activated malate transporter(ALMT9),vacuolar membrane dicarboxylate transporter(tDT),and vacuolar membrane proton pump.This study aimed to investigate the function of the VdWRKY26 gene in the growth and development of Vitis davidii fruits.The coding region(CDS)and promoter sequence of the VdWRKY26 gene were cloned from Xiangci No.1,and its function and promoter activity were further analyzed.[Methods]The Pearson correlation coefficients between VdWRKY26 gene expression data and organic acid content were calculated using the R language packages GGally and ggplot2.Us-ing cDNA from Vitis davidii fruits tissue as a template,primers were designed via the Oligo7 website for PCR amplification.The CDS region of the VdWRKY26 gene was cloned via reverse transcription polymerase chain reaction(RT-PCR).The phylogenetic tree and multiple amino acid sequence align-ments of the VdWRKY26 gene and its homologous were constructed using TBtools,MEGA 12.0,and DNAMAN software.Following the construction of a GFP-VdWRKY26 expression vector,it was trans-formed into tobacco to determine the subcellular localization of VdWRKY26.The expression levels of VdWRKY26 were measured by qPCR in different tissues of V davidii,and the promoter activity of Vd-WRKY26 was determined by GUS staining.Homologous expression in grape 41B suspension cells was used to validate its function.[Results]Pearson correlation analysis between VdWRKY26 gene expres-sion levels and organic acid content revealed that VdWRKY26 exhibited high expression during the ear-ly stages of fruit development and low expression during the later stages,showing a significant positive correlation between VdWRKY26 gene expression levels with organic acid accumulation in V.davidii fruits.Sequence analysis indicated that the coding region of VdWRKY26 gene spans 1434 bp,encoding 477 amino acids.Phylogenetic analysis of VdWRKY26 and its homologous genes showed that Vd-WRKY26 belonged to the same clade as petunia PhPH3,pear PbWRKY26 and apple MdWRKY126.Using DNAMAN software to align the VdWRKY26 protein sequence with its homologous sequences from V.vinifera,apple,pear,tomato,Arabidopsis,Petunia,and Citrus,it was found that this protein contains a WRKY domain encompassing the β2,β3 and β4 regions.Subcellular localization analysis re-vealed that the GFP-VdWRKY26 protein was primarily localized in the nucleus.Subsequently,qPCR was used to detect the expression levels of VdWRKY26 in roots,stems,young leaves,fruits at 13 days after flowering(DAF),fruits at 49 DAF,fruits at 88 DAF,and fruits at 130 DAF.Results revealed that VdWRKY26 exhibited higher expression levels in leaves,fruits at 13 days after flowering(DAF),and fruits at 49 DAF,while showing relatively lower expression in roots and stems.This indicates that the gene may play a key regulatory role during the early stages of leaf and fruit development.Analysis of ciss-acting elements in the VdWRKY26 promoter via the PlantCARE website predicted that this promoter primarily contains the light-responsive element Box4 and participates in drought-induced elements such as MBS.Subsequently,transient transfection was performed in tobacco plants followed by GUS stain-ing analysis.Results showed distinct blue staining in leaves at the transfection site,while no staining was observed in the empty vector control group,confirming the activity of the cloned VdWRKY26 gene promoter.Homologous expression of the VdWRKY26 gene was performed in grape 41B suspension cells,using empty vector-transformed grape 41B cells as controls.The expression levels of the Vd-WRKY26 gene in the control group(EV)and VdWRKY26 transgenic grape 41B cells was detected by qPCR.Results showed that the expression level of VdWRKY26 in the transgenic grape 41B cells was on-ly 32.135％of that in the empty vector transgenic control cells,indicating a co-suppression phenome-non.High-performance liquid chromatography was used to determine the organic acid content in EV and 35S:GFP-VdWRKY26 transgenic grape 41B cells.It was found that the malic acid content in 35S:GFP-VdWRKY26 transgenic grape 41B cells was significantly lower than that in the control group,while the citric acid content showed no significant changes.This confirmed that VdWRKY26 primarily participates in the regulation of malic acid accumulation in grapes.[Conclusion]This study cloned the CDS region and promoter sequence of the VdWRKY26 gene and analyzed its function.VdWRKY26 ex-hibits higher expression levels in leaves and fruits than that in roots and stems,showing high expression levels during the early stages of fruit development.The cloned 2545 bp promoter sequence of the Vd-WRKY26 gene exhibits promoter activity.The VdWRKY26 protein is localized in the cell nucleus and possesses the function of regulating malic acid accumulation in grapes.

Abstract:[Objective]Shine Muscat(Vitis labrusca × V.vinifera)is a globally dominant table grape cultivar,valued for its rose aroma,crisp texture,and excellent storage performance.Pollen viability,a critical factor in reproductive biology,directly affects pollination efficiency,fruit set,and hybrid breed-ing success.However,systematic studies on the influencing factors and regulatory mechanisms of its pollen viability remain limited,hindering improvements in breeding efficiency and fruit quality.This study aimed to investigate factors affecting pollen viability of Shine Muscat grape and related physio-logical mechanisms,optimize pollen collection storage,and pollination techniques,and provide theoreti-cal and technical support for hybrid breeding and production.[Methods]Healthy 4-year-old Shine Mus-cat grape plants in the grape germplasm nursery of Henan Institute of Science and Technology were se-lected.Anthers were collected from plump inflorescences at the early messenger flower stage,and dried at 25℃ to release pollen.Pollen quantity was determined using a hemocytometer:30 anthers were dried at 50℃,suspended in 20％sodium hexametaphosphate solution,and counted under a microscope.Pollen viability was evaluated via orthogonal test design and fluorescent staining.Based on the L4(23)orthogonal experimental design,four media(T1-T4)were formulated with specific combinations of su-crose,boric acid,and calcium chloride.The detailed matrix compositions are as follows:T1(10％su-crose+50 mg·L-1 boric acid+20 mg·L-1 calcium chloride),T2(10％sucrose+100 mg·L-1 boric acid+40 mg·L-1 calcium chloride),T3(15％sucrose+50 mg·L-1 boric acid+40 mg·L-1 calcium chloride),and T4(15％sucrose+100 mg·L-1 boric acid+20 mg·L-1 calcium chloride).All media were prepared by first dissolving 7 g·L-1 agar powder,then sequentially adding the above components.After adjusting the volume,the pH was adjusted to 6.0,and the media were dispensed into Petri dishes while hot to form germination beds for in vitro pollen culture.The orthogonal test included the four media with vary-ing concentrations of sucrose(10％or 15％),boric acid(50 mg·L-1 or 100 mg·L-1),and calcium chlo-ride(20 mg·L-1 or 40 mg·L-1);in vitro germination rate was calculated after culturing at 25℃ with 60％-70％relative humidity.Fluorescein diacetate(FDA)staining was used for rapid viability assess-ment:pollen was stained with 0.02 mg·L-1 FDA working solution,observed under a fluorescence micro-scope,and the proportion of viable pollen(with strong green fluorescence)was counted.For storage ex-periments,pollen was stored at 4℃ or-80℃ for 5 d or 7 d(with fresh pollen as CK)before viability check,with 3 biological replicates per treatment.Physiological indices measured included soluble sug-ars(SS)which was measured via anthrone colorimetry,soluble proteins(SP)via Coomassie Brilliant Blue G-250 method,proline(Pro)via ninhydrin colorimetry,and activities of superoxide dismutase(SOD),peroxidase(POD),and catalase(CAT)via NBT photochemical reduction,guaiacol,and potassi-um permanganate titration methods,respectively.[Results]Significant differences in pollen quantity were observed among the three plants(P＜0.05).Plant 1 produced the highest pollen quantity(24 × 104 grains/anther),which was 28.57％higher than Plant 2(18.67 × 104 grains/anther)and 38.46％higher than Plant 3(17.33 × 104 grains/anther).Intra-plant variation was minimal,with Plant 1 showing a stan-dard deviation of 0 across replicates,indicating stable pollen production within individual plants.The orthogonal test revealed significant differences in germination rates among media(P＜0.05).T4 medi-um yielded the highest germination rate for fresh pollen(95.79％),significantly exceeding T1(89.37％),T2(91.24％),and T3(92.86％).This indicated a synergistic effect of high sucrose(15％)and boric acid(100 mg·L-1)in promoting germination,with calcium chloride(20 mg·L-1)playing a secondary role.Storage temperature and duration significantly affected pollen viability(P＜0.05).After 5 days of stor-age,germination rate in treatment at-80℃(73.73％-88.26％)was 15％-20％higher than at 4℃(63.67％-73.54％).After 7 days of storage,treatment at-80℃ maintained higher viability(79.23％-87.98％)compared to 4℃(55.75％-68.75％),with the T4 treatment showing a 57.8％higher germina-tion rate at-80℃ than at 4℃.FDA staining confirmed that viable pollen(strong green fluorescence)was more abundant and stable under-80℃,consistent with germination rate result.Fresh pollen exhib-ited the highest levels of SS,SP,Pro,and antioxidant enzyme(SOD,POD and CAT)activities.All indi-ces decreased with storage time,but the decline was significantly slower at-80℃ than at 4℃.For exam-ple,SS content in fresh pollen(1.2 mg·g-1)dropped to 0.8 mg·g-1 after 7 days at-80℃ but to 0.5 mg·g-1 at 4℃.Similarly,SOD activity(150 U·g-1 in fresh pollen)decreased to 100 U·g-1 at-80℃(7 days)versus 80 U·g-1 at 4℃.Pearson correlation analysis showed extremely significant positive correlations(P＜0.001)between pollen viability and all measured indices.Correlation coefficients ranged from 0.856(SP)to 0.915(SOD),indicating that nutrient contents and antioxidant enzyme activities were strongly associated with the maintenance of pollen viability.[Conclusion]This study demonstrates sig-nificant intra-varietal variation in pollen quantity among Shine Muscat plants,highlighting the impor-tance of selecting high-pollen-yield plants as paternal parents in breeding.T4 medium(15％sucrose+100 mg·L-1 boric acid+20 mg·L-1 CaCl2)is optimal for in vitro pollen germination.-80℃ ultra-low temperature storage effectively preserves pollen viability by slowing the degradation of nutrients(SS,SP and Pro)and maintaining antioxidant enzyme activities.The established"pollen viability-physiologi-cal indices"correlation model provides a quantitative tool for assessing pollen quality.These findings optimize pollen management techniques,which may improve hybrid breeding efficiency.

Abstract:[Objective]Kiwifruit(Actinidia spp.)production in China maintains the world's leading po-sition in both cultivation area and yield.However,postharvest softening of fruit notably reduces its qual-ity.The initiation of fruit postharvest softening of kiwifruit primarily involves the hydrolysis of starch.The hydrolysis of starch into glucose and fructose necessitates phosphorylation for entry into the glyco-lytic pathway.Plant fructokinases(FRK)belong to the phosphofructokinase B family and possess char-acteristic substrate recognition regions of the FRK family.The FRK is a specific enzyme is involved in fructose phosphorylation,regulating fructose flux in plant cells and subsequently modulating respirato-ry metabolic pathways.Furthermore,the plant FRK may function similarly to hexokinases in sugar sensing,serving as a signaling molecule to regulate plant growth,development,starch accumulation,and environmental stress responses.However,little is known about the role of FRK in fruit postharvest softening and senescence.This study sought to identify the kiwifruit FRK gene family,investigate the differential expression patterns,and explore its association with kiwifruit softening.[Methods]Using Arabidopsis thaliana,Lycopersicon esculentum,and Manihot esculenta FRK nucleotide sequences as references,kiwifruit FRK family members were identified from the kiwifruit genome database Hong Yang v3,the HMMER online tool was used to verify the presence of the pfkB conserved domain in ki-wifruit FRK family members,then the NCBI-CDD website was utilized to further validate the character-istic substrate recognition domain of AcFRK genes.We used the TBtools software to analyze the chro-mosomal localization of AcFRK genes;the subcellular location of the kiwifruit FRK proteins was predi-cated using WoLF PSORT online website;the protein molecular weight and isoelectric points were ana-lyzed using EXPASY online website.A phylogenetic relationships of FRK proteins across kiwifruit,Arabidopsis,tomato,and cassava were established using MEGA(version 5.05)software;multiple se-quence alignments were performed using Clustal X(version 1.81)and Gendoc 32;the conserved motifs of kiwifruit FRK proteins were analyzed using the MEME online website;the exon-intron gene struc-tures were analyzed by TBtools;the FRK protein secondary structure was analyzed using SOPMA;the FRK protein tertiary model was constructed using SWISS-MODEL website;the promoter cis-acting ele-ments of AcFRKs were predicted using PlantCARE online website;and the expression heatmap of Ac-FRKs during postharvest softening were generated using TBtools by normalizing FPKM values from transcriptomic data.The expression profiles of the AcFRK2 and AcFRK4 were verified with the real-time quantitative PCR technique after glucose,fructose and various hormones treatment.[Results]In the kiwifruit genome,a total of 6 FRK sequences were identified,randomly distributed on 5 chromo-somes.The lengths of these 6 FRK proteins varied from 168 aa to 457 aa,with isoelectric points rang-ing from 4.88 to 6.03 and molecular weights spanning from 18.47 kDa to 50.01 kDa.Furthermore,the phylogenetic tree analysis revealed that kiwifruit FRK family could be divided into two groups:Ac-FRK 1/AcFRK3/AcFRK4(Group Ⅰ),AcFRK2/AcFRK5(Group Ⅱ a),and AcFRK6(Group Ⅱ b),each group comprising three FRK members.The multiple sequence alignments showed that AcFRK proteins possessed pfkB,substrate recognition,and ATP binding domains,members within the same group shar-ing highly similar conserved domains.The gene structure analysis showed that the AcFRK genes com-prised 1 to 3 UTRs,2 to 4 exons of GroupⅠ,and 6 to 9 exons of Group Ⅱ.Additionally,the amino acid sequence analysis unveiled 12 conserved motifs and demonstrated a high level of conservation among proteins within the same group,these findings were consistent with the multiple sequence alignments analysis.The protein structure analysis revealed a significant resemblance in the main structure among members of the same group,suggesting a strong conservation of functions within AcFRK proteins.The analysis of promoter cis-acting elements found a wide distribution of elements responsive to ethylene,abscisic acid,osmotic stress,and oxidative stress responses,suggesting that the AcFRK genes would be likely induced by the hormones ethylene or ABA,thereby participating in kiwifruit ripening and soften-ing.The gene expression heatmap demonstrated an upward trend in the expression levels of the Ac-FRK2 and AcFRK4 as kiwifruit ripening progresses.The correlation analysis revealed a negative associ-ation between genes and fruit firmness as well as starch content,while showing a positive correlation with reducing sugar content,indicating that the AcFRK2 and AcFRK4 might positively regulate kiwi-fruit softening.Hexose treatment experiments demonstrated that the AcFRK2 and AcFRK4 exhibited up-regulation in response to hexose,indicating their potential for efficient utilization of glucose and fruc-tose.The hormone treatment experiments demonstrated that the AcFRK2 and AcFRK4 were upregulated by ethylene induction during the late storage period,with the AcFRK4 expression being further inhibit-ed by AsA and NAA during room temperature storage,indicating that the AcFRK2 and AcFRK4 might be involved in the softening process through their response to different hormones.[Conclusion]Six members of the FRK gene family were identified,and two key genes,the AcFRK2 and AcFRK4,were selected,which would be involved in sugar metabolism,plant hormones,and kiwifruit softening.This would provide a theoretical basis for further exploring the biological functions of the FRK genes in ki-wifruit postharvest softening.

Abstract:Native to China and known for its remarkable cold tolerance,many Actinidia arguta varieties are currently developed and have been predominantly cultivated in Northeast and Central China.While the Qinling-Bashan region of Shaanxi is exceptionally abundant in wild resources of Actinidia arguta,its development and utilization remain inadequate and further improvement in exploration and evalua-tion are needed,compared to Actinidia deliciosa.In 2003,the wild kiwifruit resource survey on the northern slopes of the Qinling Mountains in Shaanxi was conducted and a distinctivewildActinidia ar-guta specimen was discovered.Characterized by red skin,red flesh,and relatively large fruits,it was named as Ziyan.Through grafting and systematic observations on botanical traits,fruit characteristics,and genetic evaluations,Ziyan demonstrated stable and distinct features:large fruit size,red skin and flesh,unique flavor,high yield,and strong stress resistance.After six years of regional trial evaluations from 2016 to 2022,the breeding process was accomplished,and the variety was registered in 2024.Zi-yan is tetraploid female variety featured with cylindrical fruit shape and smooth surface,averaging 29.09 g in weight and having a fruit shape index of approximately 1.60.The skin,flesh,and core of the fruit all turn purplish-red when fruits are ripe.With a unique flavor,the fruit offers a perfect balance of sweet and sour taste for directly fresh consumption after harvest,and contains a soluble solids content of 15.01％,total sugars of 13.20％,total acids of 0.86％,vitamin C of 2040 mg kg1,and total anthocyan-in content of 407.25 mg kg1.The fruit has a shelf life of over 3-5 days under ambient conditions and 30-45 days when stored at 1.0±0.5℃.In the Guanzhong area of Shaanxi Province,phenological develop-ment includes budbreak in mid-March,flowering in early May,and fruit maturation in late September,with a fruit growth period of 145-150 days.The variety demonstrates vigorous growth with robust branching,showing a sprouting rate of 66.98％and branching rate of 66.27％.Fruit bearing primarily occurs on spurs.The variety displays strong resistance to drought,heat,and cold,while maintaining an extremely low incidence rate of canker disease and other plant pathogens.It is suitable for cultivation in northern Qinling foothills,southern areas of Shaanxi with high-altitude,and similar ecological regions,achieving average yields of 12.75 t·hm-2 during peak production periods.In practical production,it can be used as a distinctive kiwifruit variety for modern agricultural sightseeing and picking.Orchard estab-lishment should be in the sites of well-drained and irrigated loamy soil with soil layer＞1 m,pH 6.5-7.5,and organic matter content＞1％.Planting spacing should be 3 m × 4 m,using NDM07 as the polli-nizer with female/male ratio of(6-8):1.Horizontal trellis system with"single main trunk and dual ma-jor vines"shape is recommended.Winter pruning focuses on minimal cutting,while summer pruning emphasizes shoot pinching.Flower/fruit management and fertilizer/water regulation should be strength-ened,with fully decomposed cake fertilizer and farm manure as basal organic fertilizers,supplemented with phosphorus-potassium fertilizers and bio-bacterial fertilizers.The ground mulching should be ap-plied in planting rows and inter-row cover cropping are proposed for improving orchard conditions.During growing season,scarab beetles and spotted lanternflies should be monitored,and bird preven-tion measures should be adopted before fruit maturation.

Abstract:[Objective]Grapes are highly susceptible to various virus infection.Heat treatment com-bined with apical meristem culture is currently a commonly used method for virus elimination and is ef-fective against most grape viruses,but it is less effective in eliminating Grapevine Rupestris Stem Pit-ting associated Virus(GRSPaV).Organ regeneration refers to the in vitro culture of plant stems,leaves,or other organs under sterile conditions to regenerate new tissues and organs.This process accelerates the rate of cell division and development,thereby in creasing the probability of obtaining virus-free tis-sues and cells,from which adventitious buds can be induced to regenerate virus-free plants.This experi-ment aims to eliminate GRSPaV and other viruses through organ regeneration,thereby cultivate prima-ry virus-free planets and provide support for the theoretical and practical development of grape virus elimination techniques.[Methods]The in vitro plantlets of Sweet Scarlet grape infected with GRSPaV and Shine Muscat grape infected with Grapevine Virus E(GVE),grapevine fabavirus(GFabV),and GRSPaV were studied.The subculture medium for Sweet Scarlet grape and Shine Muscat grape was B5+0.5 mg·L-1IAA+25 g·L-1 sucrose+6 g·L-1 agar,and B5+0.3 mg·L-1 IBA+0.5 mg·L-1IAA+25 g·L-1 glucose+6 g·L-1 agar,respectively.The appropriate amount of cytokinin and auxin in B5 basal medium were screened by supplied(4.0,5.0 mg·L-1)BA+(0.1,0.2,0.3 mg·L-1)IAA,and 2.0 mg·L-1 TDZ+(0.1,0.2,0.3 mg·L-1)IAA or(0.1,0.2,0.3 mg·L-1)NAA.The addition of TDZ to B5 basal medium were test-ed at concentrations of 0.5,1.0,2.0,2.5,and 3.0 mg·L-1 levels.The sodium nitroprusside(SNP)was supplied to MS or B5 basal medium at concentrations of 0,4,6,8,10,and 12 mg·L-1 to evaluate its effi-ciency for the regeneration of adventitious buds from the plantlets in vitro.Based on the optimal medi-um obtained from the above experiments,Sweet Scarlet grape was directly induced to regenerate adven-titious buds from leaves in vitro.Subsequently,the adventitious buds were excised and cultured in the subculture medium.A total of sixty-three plantlets from the seven clones were obtained and subjected for the virus detection by RT-PCR analysis.For Shine Muscat grape plantlets,the in vitro cultured leaves were firstly induced to generate callus.The callus was then subcultured onto B5+1.0 mg·L-1 BA+0.1 mg·L-1 NAA+30 g·L-1 glucose medium,with subculture interval lasting 20-30 d.During each sub-culture interval,six clones of callus were randomly selected for the virus detection.The virus-free cal-lus was then transferred to B5+2.0 mg·L-1 TDZ+0.2 mg·L-1 NAA+15 g·L-1 glucose medium to induce the regeneration of adventitious buds.After virus detection,the buds were cut and subcultured to devel-op into plants.[Results]The combination of TDZ and IAA was suitable for in vitro regeneration of ad-ventitious buds from Sweet Scarlet grape leaves and for inducing callus from Shine Muscat grape leaves.In vitro leaves of Sweet Scarlet grape treated with TDZ at 1.0 mg·L-1 showed the highest adven-titious bud rate(18.06％)and the number of buds per leaf disk(0.96),significantly higher than those un-der other TDZ concentrations.The optimal medium for adventitious bud regeneration from the leaves of Sweet Scarlet grape plantlets was B5+1.0 mg.L-1 TDZ+0.1 mg·L-1 IAA+15 g·L-1 glucose+10 mg·L-1 SNP.Within the 0.5-1.0 cm leaf disk,the average number of the adventitious buds reached 1.82,repre-senting an 114.12％increase compared to the treatment without SNP.For Shine Muscat grape,the in vi-tro cultured leaf discs failed to induce adventitious bud in medium with different cytokinin and auxin factors or different concentrations of TDZ.However,the adventitious bud regeneration was success-fully induced on medium supplemented with SNP,and the optimal medium was B5+1.0 mg·L-1 TDZ+0.1 mg·L-1 IAA+15 g·L-1 glucose+8 mg·L-1 SNP,yielding an adventitious bud rate of 17.03％and an average of 1.80 buds per plantlet.The adventitious buds regenerated from the leaves of Sweet Scarlet grape were in vitro cultured into plants.Five out of seven tested clones were free of GRSPaV,achieving a virus removing rate of 71.4％.Callus was induced from the leaves of Shine Muscat grape plantlets car-rying GVE,GFabV,and GRSPaV.The first-generation callus retained all viruses presented in the origi-nal plants.Only GRSPaV was detected in the second-generation,while none of the viruses were found in the third-generation.Virus testing for the callus of the fourth generation and the subsequent con-firmed complete virus-free status.Adventitious buds were then regenerated from the virus-free callus,successfully yielding the primary virus-free plants.[Conclusion]The addition of SNP in the medium significantly promoted the adventitious bud regeneration from the leaves of Sweet Scarlet grape and Shine Muscat grape plantlets in vitro.Virus-free plants could be directly obtained via the adventitious bud regeneration either from the leaves in vitro in Sweet Scarlet grape or from the callus of the leaves in vitro in Shine Muscat grape.

Abstract:Hanxiang kiwifruit is a new Actinidia chinensis cultivar selected from wild kiwifruit popula-tion.Excellent wild resources were found in Wudang Mountain,Shiyan City,Hubei Province,in 2007,seeds were sown in 2008,a single plant with strong growth potential and beautiful fruit shape was se-lected in 2013(No.Wudang 07-1-4),and graft observation was made in 2013.After continuous observa-tion over several years,it was found that this superior strain exhibited stable performance and a strong tree structure.New variety protection was applied for in 2019,and new variety right certificate was ob-tained in 2024(variety name Hanxiang)with the variety right number CNA20191001687.The annual branch is reddish brown,the epidermis is rough,and there are short fusiform yellow pores.Leaf blade is sub fan,with heart-shaped base,adaxially medium green color,no or very sparse fuzz,and weak corru-gation,abaxially light green color,and medium density fuzz.The flowers are mostly solitary,with white petals,5-7 sepals,2.8-3.5 cm corolla in diameter,light green filaments,yellow anthers,white style,hor-izontal growth,and 2.1-2.7 cm stalk in length.The fruit is obovate,the maximum single fruit weight is 85.6 g,and the average single fruit weight is 73.8 g.Fruit surface is covered with yellowish brown short hairs and easy to fall off.The beak of the fruit is shallow concave,the shoulder is round,the calyx ring of the fruit is obvious,and the stalk is longer,averaging 4.99 cm.The peel is light brown or brown,the fruit is easy to fall off after maturity,and the peel is difficult to peel off.The core is yellowish-white and oval.The outer flesh is light yellow,and the inner flesh is yellow.Fruit soluble solid content is 19.6％,soluble sugar content is 12.04％,total acids content is 1.25％,and vitamin C content is 750.4 mg kg-1.When an orchard is built,the spacing between the plants should be 3 m ×(4-4.5)m.It is recommended to use Moshan Xiong 2 or other male varieties whose flowering periods coincide with it,and the ratio of males to females is usually(6-8):1.Generally,fertilization is applied three times a year.The germi-nation fertilizer is mainly nitrogen fertilizer,combined with potassium fertilizer application.The fruit swell fertilizer is mainly applied with nitrogen,phosphorus and potassium combined with human and animal manure water.After picking fruit,apply base fertilizer after digging a circular or semi-circular trench 35 cm deep and 30 cm wide around the tree disc,with the decomposed organic fertilizer.Pay at-tention to soil moisture management,timely irrigation in high temperature drought resistance and tree disc covering;Pay attention to timely drainage in rainy season.One trunk with two main vines re-mained is recommended.When pruning in winter,the amount of buds left should be appropriate,and in summer,attention should be paid to removing superfluous buds,sprouting and pinching.In the western part of Hubei Province,Hanxiang begins to sprout in early to mid-March,reaches its peak flowering in mid-April,with a flowering period of 4 to 6 days,and the fruits mature in late September.The north-west Hubei or similar climatic regions are suitable for cultivation.

Abstract:[Objective]Temperature plays a critical role in insect growth and development,influencing key biological traits such as longevity,feeding behavior,and mating success.These factors,in turn,di-rectly affect population dynamics and developmental trends.Pear psylla Cacopsylla chinensis,one of the major pests in pear,exhibits high sensitivity to temperature fluctuations.Notably,temperature varia-tions also impact the growth and development of these host plants.The study aimed to better understand the effects of rising temperatures on the emergent overwintering C.chinensis(winter form of pear psyl-la)and its phenological synchrony with pear trees,and to clarify its occurrence and development trend under the background of global climate warming.[Methods]This study examined the effects of spring temperature elevation on the pear psylla by simulating pregermination phenological conditions of pear tree,under the condition of only providing dormant pear branches to pear psylla.The life span,pre-ovi-position period,fecundity and egg hatching period of pear psylla under different treatment temperatures(5℃,10℃,15℃,20℃,25℃,30℃)were tested,the flower bud germination period of host pear tree under the same setting temperature were measured as well.The phenological correlation between the pear psylla and the host pear tree under different temperature conditions were analyzed.The devel-opmental threshold temperature and effective accumulated temperature of flower bud germination,pear psylla oviposition and offspring hatching were studied by law of effective accumulated temperature method.[Results]Results showed that the life span of the pear psylla decreased significantly with the increase of temperature.At 50％mortality,the survival durations under different temperature conditions were as follows:5℃(24.16 d),10℃(18.05 d),15℃(7.25 d),20℃(7.56 d),25℃(5.80 d),and 30℃(5.28 d).The average life span of pear psylla under 5℃,10℃,15℃,20℃,25℃ and 30℃were 47.09 d,36.81 d,18.50 d,13.3 d,10.12 d and 7.37 d,respectively.The duration of the pre-oviposi-tion period of the pear psylla was significantly shortened with the increasing of temperature,the pre-ovi-position period of the pear psylla were 47 d at 5℃,when the temperature ≥ 25℃,the pre-oviposition period were 3-4 d.5℃ and 30℃ were unfavorable for the oviposition,the oviposition duration was 7 d to 9 d,the highest number of eggs was 93.5 at 25℃.The number of eggs laid ranged from 65 to 94,and there was no significant difference between 10℃ and 25℃.The duration of pear flower bud ger-mination became shorter with the increase of temperature.When the temperature was less than 10℃,the time of flower bud germination was over 30 d.When the temperature was 15-20℃,the time of flower bud germination was similar,which ranged from 17 d to 19 d.When the temperature was higher than 25℃,it ranged from 7 d to 9 d.At ≥25℃,eggs exhibited the shortest incubation rate(10.67 d)and the highest incubation rate,indicating that this temperature was optimal for egg incubation.At 10-20℃,egg incubation rate ranged from 13.33 to 30.33 d.At 5℃,the incubation rate was the lowest and the incubation duration the longest,demonstrating that 5℃ was unfavorable for incubation of the win-ter-form pear psylla eggs.The developmental threshold temperatures of the pre-oviposition,egg hatch-ing,pre-oviposition and egg hatching,flower bud germination were 4.46℃,0.99℃,2.54℃ and 4.51℃,respectively,and the effective accumulated temperature was 115.25 days degree,248.67 days degree,368.51 days degree,187.59 days degree,respectively.Through the curve fitting of the life span,pre-oviposition period,egg hatching,and the length and temperature required for flower bud germina-tion of pear trees,it was found that their trends were consistent.The pre-oviposition period of pear psyl-la was consistently shorter than pear flower bud germination time across all tested temperature regimes.When the pear psylla oviposited,the pear flower bud did not germinate.When the pear psylla is close to death,it is the time of pear flower bud began to sprout.Egg of the winter form of pear psylla always hatched later than the germination of the pear tree,there is no shortage of food for the offspring.The oviposition-to-hatching period matched with pear flower bud germination time,ensuring offspring food availability.[Conclusion]Rising temperatures shortened the reproductive development period and life span of the pear psylla.However,higher temperatures also led to concentrated oviposition,decreased egg hatching time and a reduced oviposition period.When the temperature was above 20℃,it signifi-cantly favored the occurrence and reproduction of the pear psylla,and the damage they caused intensi-fied.Additionally,elevated temperatures influenced the phenological development of the pear psylla's host plants,accelerating the pear flower bud germination.Interestingly,the response of the pear psylla to temperature changes closely matched with the host plant,suggesting strong phenological synchrony with minimal disruption from temperature fluctuations.When nutritional resources for the overwinter-ing pear psylla were depleted,the pre-germination of the pear flower buds allowed the pear psylla to re-plenish nutrients promptly.Alternatively,they could temporarily feed on non-host plants before repro-duction.Notably,post-germination fertility of the pear psylla was significantly higher than that during the dormancy period,exacerbating damage to the pear trees.These findings would provide a theoretical basis for predicting population dynamics and improving pest management strategies against the pear psylla under climate change condition.

Abstract:[Objective]The AP2 subfamily transcription factor represents one of the most important transcription factor families in plants,playing pivotal roles in regulating various biological processes in-cluding floral organ morphogenesis,embryogenesis,meristem differentiation,leaf morphology estab-lishment,and biotic and abiotic stress responses.Despite their well-characterised functions in model plants,systematic investigation of AP2 family in economically important fruit crops like Chinese plum(Prunus salicina Lindl.)remains limited.This study presented the first comprehensive genome-wide identification of AP2 transcription factors in three major Chinese plum cultivars Sanyueli,Zhongli No.6,and Wushancuili.[Methods]Using high-quality genome assemblies of the three plum cultivars,we sys-tematically identified AP2 family members through comprehensive bioinformatics approaches.Multiple sequence alignment and phylogenetic analysis were conducted using MEGA 11 with AP2 proteins from Arabidopsis thaliana,Malus domestica,and other related species.Gene structure and conserved motifs were analyzed using SMART and MEME suites.Chromosomal locations and synteny relationships were determined using MCScanX.Cis-acting regulatory elements in promoter regions were predicted using PlantCARE.Expression patterns were investigated through qRT-PCR analysis of six selected AP2 genes(SYPsAP2-5/7,ZLPsAP2-15/16,and WSPsAP2-9/11)across eight fruit developmental stages in Shibanwannai plum.[Results]We identified 20,22,and 18 AP2 genes in Sanyueli,Zhongli No.6,and Wushancuili genomes,respectively.The expansion and contraction of the AP2 gene family were likely closely associated with species'evolutionary history and ecological adaptation.The size of the plum AP2 gene family not only reflected shared characteristics within Rosaceae plants,but also demonstrated genus-specific adaptations in Prunus species.The relatively conserved number of AP2 genes in stone fruits may be related to their specific developmental regulatory requirements.The subcellular localiza-tion prediction results indicated that the AP2 family members in the three plum varieties were predomi-nantly localized in the nucleus(48 out of 60,80％;16 in Sanyueli,17 in Zhongli No.6,and 15 in Wushancuili).A small number of AP2 family members were distributed in organelles such as chloro-plasts and peroxisomes.This distribution pattern was consistent with the typical subcellular localization pattern of transcription factors.Referring to the classification criteria of the Arabidopsis thaliana AP2 transcription factor family,the plum AP2 transcription factor family was divided into 13 subfamilies,in-cluding the AP2-type,RAP2-7-type,T11A7.19-type,WRIl-type,ADAP-type,ANT-type,AIL5-type,AIL6-type,AIL 1-type,BBM-type,PLTl-type,PLT2-type,and TOE-type.From the perspective of spe-cies phylogenetic relationships,the AP2 gene members of the three plum varieties clustered together and exhibited closer phylogenetic relationships compared to those of Rosaceae species like apple and pear.This finding is consistent with their systematic taxonomic status.Chromosomal distribution re-vealed uneven gene dispersion,with Chrl being a hotspot in Sanyueli(35％).This distribution pattern indicated a clear chromosomal preference.The intraspecies synteny analysis revealed that the genome of Sanyueli contained 3 pairs of SYPsAP2 syntenic genes,while Wushancuili harbored 4 pairs of WSP-sAP2 syntenic genes.Among the three plum varieties,Zhongli No.6 exhibited the most extensive syn-tenic relationships within the ZLPsAP2 family,with a total of 7 pairs of ZLPsAP2 syntenic genes identi-fied.Motif 2 was conserved across all 60 PsAP2 members and served as the core motif.Motifs 2,4,1,and 5 were most frequent,typically arranged orderly and biased toward the 5'end.Protein domain anal-ysis showed that all PsAP2 members possessed the canonical double AP2 domain.Notably,WSPsAP2-3 contained additional Amb all and Pec_lyase_N domains,while SYPsAP2-19 harbored a dermokine su-perfamily domain at its C-terminus.These unique domains suggested potential evolutionary divergence and novel functions for these genes.Cis-acting element analysis of the AP2 gene family promoters in plums revealed significant enrichment of diverse response elements.The three plum varieties shared several core response elements:light-responsive elements(282 in SYPsAP2,307 in ZLPsAP2,and 226 in WSPsAP2),abscisic acid-responsive elements(66 in SYPsAP2,62 in ZLPsAP2,and 52 in WSP-sAP2),MeJA-responsive elements(40 in SYPsAP2,48 in ZLPsAP2,and 32 in WSPsAP2),gibberellin-responsive elements(25 in SYPsAP2,28 in ZLPsAP2,and 23 in WSPsAP2),and anaerobic induction el-ements(52 in SYPsAP2,57 in ZLPsAP2,and 49 in WSPsAP2).Each variety had distinct regulatory fea-tures.For example,Sanyueli(SYPsAP2)had a higher number of MYBHv1 binding sites(20)compared to Zhongli No.6(6)and Wushancuili(8),indicating a potential role in MYBHv1-mediated regulation.Zhongli No.6(ZLPsAP2)had the most diverse and abundant ciss-acting elements,suggesting a complex regulatory network for its AP2 genes.Wushancuili(WSPsAP2)contained unique wound-responsive ele-ments,likely involved in plant wound response mechanisms.Specific AP2 gene family members may be involved in seed development and light signal transduction.SYPsAP2-7/11,ZLPsAP2-3/16,and WSPsAP2-1/11 contained seed-specific regulatory elements.SYPsAP2-2,ZLPsAP2-18,and WSPsAP2-6 contained phytochrome regulatory elements.Six representative genes from the AP2 and BBM clades were selected based on phylogenetic and promoter analyses.Their expression patterns were analyzed across eight developmental stages of Shibanwannai,revealing significant tissue-specific profiles.The gene expression profiling demonstrated that AP2 clade genes(SYPsAP2-5,ZLPsAP2-15,and WSSPsAP2-9)showed peak expression during early fruit development and the BBM clade genes(SYPsAP2-7,ZLP-sAP2-16,and WSPsAP2-11)exhibited seed-specific expression,with dramatic upregulation during T4-T8(from 88 to 148 days after full bloom)stages coinciding with seed abortion events.[Conclusion]The PsAP2 subfamily genes of Chinese plum were identified and analyzed in detail at the genome-wide level.The temporal-spatial expression characteristic of this subfamily genes was studied,which would establish a foundation for future functional studies and molecular breeding applications targeting fruit quality and seed development traits in plum.The identification of seed-specific PsAP2 regulators offers promising targets for addressing seed abortion issues in plum production.

Abstract:[Objective]Litchi(Litchi chinensis Sonn.)is an economically valuable fruit species in southern China.Breeding new variety is very important for meeting consumer needs and improving eco-nomic efficiency.However,the species'allogamous reproductive strategy drives extreme genomic het-erozygosity,presenting formidable barriers to precision breeding and genetic manipulation.To address these constraints,cell suspension culture emerges as a transformative biotechnological platform,offer-ing dual strategic capacities.It would generate homogeneous cell populations essential for protoplast isolation,somatic hybridization,and transgenic development;Moreover,it would enable industrial-scale biosynthesis of high-value phytochemicals.This study systematically optimized critical parame-ters governing litchi anther-derived callus growth in suspension systems,including macro-/micronutri-ent formulations(inositol,2,4-D,sucrose),organic growth modulators[lactalbumin hydrolysate(LH),coconut water(CW)],and inoculation density thresholds.The multifactorial optimization strategy aimed to establish a robust,scalable suspension culture protocol yielding high-quality embryogenic cul-tures,thereby creating foundational biomaterials for advanced applications in litchi protoplast technolo-gy and cross-species genetic engineering initiatives.[Methods]Anther-derived embryogenic callus of Feizixiao litchi was used as the initial material.Suspension cultures were established in liquid MS medi-um under dark conditions(25±2℃,120 r·min-1).A series of experiments were conducted to optimize culture conditions:Inositol(0-0.2 g·L-1),2,4-D(0.1-2 mg·L-1),sucrose(10-40 g·L-1),LH(0-0.4 g·L-1),CW(0-200 mL·L-1),and inoculum densities(10-40 g·L-1)were tested for their effects on cell prolifera-tion,single-cell viability,and biomass.Suspension cultures were subculture every 4 days,filtered through a 0.85 mm sieve,and monitored for growth parameters[fresh weight(FW),dry weight(DW),packed cell volume(PCV),pH,conductivity).Embryogenic callus proliferation,somatic embryo differ-entiation,maturation,and plant regeneration were induced using specific solid media supplemented with growth regulators(NAA,ZT,ABA)and high sucrose concentrations.[Results]Single-factor trial results showed that the effects of inositol,2,4-D,sucrose,CW and initial inoculum density on the callus morphology(single cell,little cell group and density)and proliferation rate(FW,DW)were significant(P＜0.05),while the effect of LH was not significant.The embryogenic suspension system of litchi was established.The optimal treatment regimen was as follows:Anther embryogenic callus of Feizixiao li-tchi was inoculated into liquid medium containing MS+inositol 0.15 g·L-1+2,4-D 1 mg·L-1+sugar 20 g·L-1+CW 50 mL·L-1.The initial inoculum density was 1.5 g per 50 mL of culture medium.The suspension culture was maintained under dark conditions at(25±2)℃ with 120 rpm orbital shaking.The subculturing was performed every 4 days for 3-4 cycles,followed by filtration through 0.85 mm mesh,after that the subculturing interval was extended to 7 days.After approximately 20 days of total cultivation,an optimal suspension cell line was obtained,characterized by predominantly round or near-round cell morphology,excellent dispersion and homogeneity,rapid cell division and growth,abundant and active cytoplasmic structures,and a clear,transparent suspension.The growth parameters of the li-tchi suspension culture(single-cell yield,biomass accumulation,and cell packed volume)followed a sigmoidal("S"-shaped)growth curve.The culture progression was divided into three phases:lag phase(days 1-2):minimal single-cell dispersion,slow increases in FW,DW and packed cell volume(PCV),logarithmic growth phase(days 3-6):rapid cell division with significant increases in single-cell count,FW,DW,and cell density,and stationary phase(days 7-16):stabilized cell growth with gradual increases in FW,DW and PCV.Beyond this phase,the prolonged culture led to cell senescence and fragmentation,accompanied by sharp declines in viable cell count and survival rate,with minimal increases in FW,DW and PCV.The pH of the suspension initially showed a slight increase followed by continuous decline throughout the culture period.The electrical conductivity exhibited a consistent downward trend during the entire suspension culture process.[Conclusion]An optimized embryogenic suspension system was successfully established for Feizixiao litchi using MS medium supplemented with inositol 0.15 g·L-1,2,4-D 1 mg·L-1,sucrose 20 g·L-1,and CW 50 mL·L-1.This system exhibited high uniformity,rapid pro-liferation,and stable embryogenic potential,enabling efficient somatic embryo production and plant re-generation.The findings could advance litchi biotechnology applications,including mutagenesis,proto-plast isolation,and synthetic seed production,and offer a reference for recalcitrant woody species.

Abstract:[Objective]Pomegranate(Punica granatum L.),distinguished by its exceptional environmen-tal adaptability and extensive cultivation history in China,has emerged as a globally significant econom-ic tree crop.As a primary pomegranate production region within China,Shandong Province faces sub-stantial challenges in germplasm resource management.Being predominantly cross-pollinated,cultivat-ed pomegranates in the region exhibit considerable genetic complexity arising from spontaneous somat-ic mutations,introductions of germplasm from diverse geographical sources,and extensive varietal ex-change.Consequently,this has resulted in pronounced varietal disorganization,ambiguous genetic rela-tionships,and significant lineage confusion,collectively impeding the efficient conservation and utiliza-tion of pomegranate germplasm resources.Furthermore,accelerated commercial breeding programs have exacerbated genetic homogenization,rendering conventional morphological identification meth-ods inadequate for precise varietal discrimination and classification.This critical limitation severely constrains the development of elite cultivars and hinders the sustainable advancement of the pomegran-ate industry.To address these challenges,this study employed Inter-Simple Sequence Repeat(ISSR)molecular markers to investigate the genetic diversity and elucidate the genetic relationships among 76 distinct pomegranate germplasm accessions native to Shandong Province.The primary objective was to construct a robust DNA fingerprinting system,providing scientific foundation for enhancing germplasm preservation,formulating efficient breeding strategies,and achieving precise molecular identification of pomegranate genetic resources.[Methods]Experimental materials comprised 76 authenticated pome-granate(Punica granatum L.)germplasm accessions systematically curated from the China Pomegran-ate Germplasm Resources Nursery located in Zaozhuang City,Shandong Province.Genomic DNA was extracted from fresh young leaf tissue using a modified cetyltrimethylammonium bromide(CTAB)pro-tocol.Sixteen ISSR primers with clear amplification bands and high polymorphism were selected for PCR amplification of 76 pomegranate germplasm accessions.PopGene software was used to calculate:Mean number of observed alleles per locus(Na),Effective number of alleles per locus(Ne),Nei's unbi-ased gene diversity index(He),and Shannon's information index(I)for population genetic diversity analysis.The genetic similarity coefficient(GS)was calculated using NTSYS clustering software.The genetic relationships between pomegranate germplasm accessions were analyzed by the Unweighted Pair Group Method with Arithmetic Averages(UPGMA).Based on the UPGMA clustering results,the discrimination efficiency of a single primer or primer combinations for germplasm accessions was eval-uated.Primers/combinations capable of distinguishing all accessions were selected to construct DNA fingerprints for the germplasm accessions.[Results]A total of 305 loci were detected in 76 accessions using 16 primers,of which 269 were polymorphic loci,with a primer polymorphism ratio of 88.2％.This indicated that the 16 primers exhibited good polymorphism.The results of genetic diversity analy-sis showed that mean number of observed alleles per locus(Na)was 1.980 7,effective number of al-leles per locus(Ne)was 1.651 7,Nei's unbiased gene diversity index(He)was 0.370 4,and Shannon's information index(I)was 0.545 1.These metrics collectively demonstrated that moderate to high genet-ic diversity existed within the sampled Shandong germplasm.UPGMA cluster analysis based on genetic similarity coefficients(GS range:0.49 to 0.98)clustered all 76 accessions into a hierarchical dendro-gram.At a GS threshold of 0.688,four distinct genetic clusters emerged:Group Ⅰ(n=40):Encom-passed accessions with extensive morphological variation,including red/pink flowers,single/double pet-als,and both ornamental/edible fruit types.Group Ⅱ(n=27):Contained varieties exhibiting diverse pericarp colors and floral characteristics.Group Ⅲ(n=2):Comprised morphologically distinct acces-sions.Group Ⅳ(n=7):Included varieties with heterogeneous phenotypic traits.Critically,the molecular classification exhibited incongruence with prior morphological taxonomy across all groups.Accessions in Groups Ⅲ and Ⅳ showed the greatest genetic divergence,making them prime candidates for hybrid breeding programs to exploit heterosis and introgress novel genetic variation.Notably,67 accessions(88.16％of the collection)coalesced into a single cluster at GS=0.678,indicating constrained genetic di-versity within the dominant Shandong germplasm.This finding necessitates strategic introduction of ge-netically distant elite germplasm to broaden the genetic base for sustained breeding progress.According to the UPGMA clustering results,the variety discrimination efficiency of a single primer was 15.78％to 85.52％.No single primer distinguished all 76 accessions,necessitating combinatorial screening.The primer pair UBC834/UBC835 achieved 97.37％discrimination efficiency,generating unique banding profiles for 74 accessions.Only cultivars No.75(Hydrangea Peony)and No.76(Purple Skin Sweet)shared identical fragment patterns,suggesting either recent divergence or clonal relationship.Conse-quently,a comprehensive DNA fingerprinting system was established using polymorphic markers from the UBC834/UBC835 combination,enabling unambiguous molecular identification of 74 accessions.[Conclusion]The 16 ISSR primers used in this study were able to successfully analyze the genetic vari-ation of pomegranate germplasm resources.The genetic diversity of the pomegranate population in Shandong Province was relatively rich,and the ISSR classification results were not consistent with tra-ditional morphological classification.The DNA fingerprints system of 74 accessions established in this study exhibited cultivar-specific characteristics,offering a scientific basis for the scientific classifica-tion,precise identification,and breeding of new pomegranate cultivars of pomegranate germplasm re-sources.

Abstract:[Objective]Labor-saving and simplified cultivation is an inevitable trend for fruit tree devel-opment.The tree shapes and varieties directly affect the establishment of the orchards and the produc-tion outcome.The production process is characterised by the quality of the varieties and the efficacy of the tree shapes.However,discrepancies in the process may result in suboptimal orchards establishment,and instances of failure are not uncommon.Therefore,the establishment of a system for the evaluation of tree shape and variety is imperative.The double arm parallel trellis cultivation system offers signifi-cant advantages in fruit quality,labor savings,and mechanization,making it one of the most rapidly ad-opted pear cultivation models in the middle and lower reaches of the Yangtze River.This study aims to fill existing literature gaps by systematically identifying pear varieties suitable for double-arm parallel trellis cultivation.Research indicates no prior variety screening studies specifically targeting this culti-vation model.To identify superior varieties suitable for labor-saving,simplified cultivation under dou-ble-arm parallel trellis systems,matching high-quality varieties with labor-saving tree forms is crucial.[Methods]In the present study,17 varieties of pear orchards cultivated with the double arm parallel trellis cultivation mode in the middle and lower reaches of Yangtze River production areas were select-ed as the primary research objects.The differences in growth,fruiting characteristics and fruit quality in-dexes of different varieties were investigated.Subsequently,the growth and fruit quality of different va-rieties were evaluated under the double arm parallel trellis cultivation mode using the affiliation func-tion method and VIKOR method.In the context of optimal tree growth and fruiting conditions,shorter new shoot length,reduced crown width(both east-west and north-south),decreased tree height,and a later onset of fruiting were more conducive to the management of orchard cultivation in a simplified manner.The hypothesis that reduced chew resistance is indicative of superior taste is one of that merits further investigation.Therefore,a comprehensive evaluation was conducted by the reciprocals of the aforementioned indicators.To ensure the accuracy of the assessment results,we employed the correla-tion function method to select 20 comprehensive evaluation indicators,including 1/new shoot length,germination rate,branching capacity,1/canopy width(east-west),1/canopy width(north-south),number of fruiting branches,short and medium branches ratio,long branches ratio,1/early fruiting,yield,single fruit weight,total soluble solids,titratable acid,total soluble solids/titratable acid content(TSS/TA),vi-tamin C content,flesh firmness,flesh fineness,reversibility,1/chewability and brittleness.[Results]It is evident that various varieties display marked variations in growth characteristics when cultivated within the double arm parallel trellis system,with the coefficient of variation for the parameters of long shoot ratio,branching capacity,yield,and number of fruiting shoot clusters all exceeding 35％.The co-efficients of variation of eight indexes,namely branching ability,long branching ratio,yield,number of fruiting branches,TSS/TA,titratable acid content,flesh fineness and chewability,were large and differ-entiated among different varieties under the double arm parallel trellis cultivation mode.The utilisation of the affiliation function method resulted in a comprehensive evaluation value greater than 0.70.The four pear cultivars identified were Housui,Wonhwang,Cuiguan and Yulü.The Eli No.2 evaluation yielded a value of 0.691,which was in close proximity to 0.70.A comprehensive evaluation value be-low 0.6 was observed in four pear varieties:Zaojinsu,Zhongli No.1,Zhongli No.4,and Zaosumi.In addition,the aforementioned five varieties were to be considered the most highly ranked.The applica-tion of the VIKOR method to the evaluation process indicated that the weight value assigned to early fruiting is 19.3％,representing the largest proportion.In contrast,the weight allocated to the ratio of short and medium branches was the smallest,at 2.3％.The remaining indicators fell within the interme-diate range.The top five in the comprehensive ranking were Housui,Wonhwang,Cuiguan,Yulü and Eli No.2.[Conclusion]It is evident that both the affiliation function method and the VIKOR method are forms of comprehensive evaluation of multiple indicators through weight changes.These methods have been widely utilised in other areas.The comprehensive evaluation rankings obtained by the affiliation function method and the VIKOR method are essentially equivalen,indicating that both methods can be employed for comprehensive evaluation of tree shapes and determining the suitability of different variet-ies.In the middle and lower reaches of the Yangtze River,the double-arm parallel trellis enables labor-saving and simplified cultivation of pear varieties of Housui,Wonhwang,Cuiguan,Yulü and Eli No.2.Variety adaptability evaluation is a long-term process that requires commitment and dedication.Further research and verification are needed to determine the suitability of other tested varieties.

Abstract:Kiwifruit(Actinidia Lindl.)acclaimed as the"king of fruits"due to its rich nutritional com-position,is an important horticultural crop with high economical and nutritional value.It is rich in sug-ar,vitamin C,dietary fiber,polyphenols,and various bioactive compounds,which contributes to its strong antioxidant capacity and numerous health benefits.In response to the growing market demand for high-quality,safe,and convenient fruit products,the modernization of kiwifruit harvesting and post-harvest handling has become essential for industrial advancement and sustainable development.This re-view summarizes recent progress in harvest maturity evaluation,storage and preservation techniques,ripening control,and quality regulation of kiwifruit.Studies have indicated that determining harvest ma-turity based on soluble solids content(SSC),fruit firmness,and dry matter content is critical for main-taining postharvest quality and ensuring optimal flavor potential.SSC is closely related to sugar accu-mulation and sweetness,firmness determines texture and damage resistance during transport,and dry matter serves as an effective predictor of flavor development.Scientific evaluation of these parameters provides a foundation for defining the optimal harvest period and achieving a balance between storabili-ty and eating quality.Postharvest handling has attracted considerable research attention in recent years.Low-temperature storage remains the most fundamental and effective method for slowing fruit respira-tion,suppressing ethylene biosynthesis,and extending shelf life.Variable-temperature storage simulates natural temperature fluctuations to reduce chilling injury,maintain cell membrane integrity,and pre-serve flavor compounds.Controlled-atmosphere storage further enhances postharvest stability by adjust-ing gas composition to delay senescence.The application of 1-methylcyclopropene(1-MCP),an ethyl-ene receptor inhibitor,has also been shown to effectively delay softening and maintain firmness,and nu-tritional integrity during long-term storage and transport.Ripening regulation technologies are equally important for achieving the desired eating quality of kiwifruit.Ethylene treatment promotes uniform softening and aroma development,while temperature-controlled ripening enables coordinated regula-tion of ripening and flavor formation.The integration of ethylene management with temperature control allows a more precise and controllable ripening process,thereby improving consumer satisfaction and commercial value.In addition,emerging quality regulation techniques,such as antioxidant application,calcium-based firmness regulation,and natural or edible coating treatments,have shown promising re-sults in delaying senescence and maintaining the visual and textural quality of fruit during storage.The integration of diverse preservation and ripening technologies establishes a comprehensive postharvest handling system that supports large-scale,standardized,and high-value production of kiwifruit.Further-more,the development of digital traceability,intelligent monitoring,and predictive modeling technolo-gies offers new opportunities to improve supply chain transparency and optimize storage and distribu-tion management.By combining traditional postharvest physiology with modern intelligent manage-ment tools,the kiwifruit industry can enhance product quality while promoting sustainability.In summa-ry,this review emphasizes the current progress and future perspectives of kiwifruit harvesting standard and postharvest handling technologies.It emphasizes the importance of integrating scientific harvest standards with advanced storage,preservation,and ripening strategies to maintain fruit quality and eco-nomic value.Continued research on the molecular mechanisms of ripening,digital management sys-tems,and environmentally friendly preservation technologies will further promote the sustainable and high-quality development of the kiwifruit industry.

Abstract:[Objective]Apple,a globally popular and economically valuable fruit crop,is cultivated across many regions.Apple orchard soils store significant amounts of soil organic carbon(SOC),which is crucial for maintaining soil fertility and plays an important role in the global carbon cycle.Growing concerns about soil health and climate change have turned the enhancement of SOC in apple orchards into a prominent research focus.Straw mulching,an environmentally friendly soil management prac-tice,is widely recognized for its potential to improve apple orchard soils and raise SOC content.Howev-er,how different straw mulch amounts affect SOC remains unclear,and the key question of what level of straw mulch can achieve the most significant SOC enhancement remains unanswered.Given this,the present study focuses on apple orchards in the Loess Plateau region to investigate how different straw mulch amounts affect SOC and its fractions,and to identify the optimal straw mulch amount for SOC enhancement.The findings will provide a basis for effective soil management practices,improving or-chard soil fertility and productivity while contributing to climate change mitigation.[Methods]This study was conducted in an experimental plot established in a"Red Fuji"apple orchard in Baota Dis-trict,Yan'an City,in July 2021.The apple trees in this orchard were 15 years old,with a planting densi-ty of 4 m×3 m and a tree height of approximately 385 cm.The diameter at breast height of the trees was about 16.4 cm.Five plots with different straw mulch amounts(0,100,200,300,and 400 g·m-2)were set up in the orchard.These plots were subjected to wheat straw mulching treatments each year after ap-ple harvest for the following three years.In October 2024,soil samples were collected from the 0-20 cm depth in each plot to determine SOC,particulate organic carbon(POC),mineral-associated organic carbon(MAOC),and other soil physicochemical properties.To evaluate the effects of different straw mulch amounts on SOC fractions and other physicochemical properties,one-way analysis of variance was used to determine the significant differences in SOC,POC,MAOC,and other soil physicochemical properties among the different straw mulch amounts.Subsequently,Pearson correlation analysis was employed to explore the correlations between soil properties and SOC,POC,and MAOC.Finally,step-wise regression analysis was used to identify the key factors driving the dynamics of SOC,POC,and MAOC under straw mulch conditions.The application of this series of analytical methods aimed to gain a deep understanding of the mechanisms by which straw mulch affected soil carbon cycling in apple or-chards.[Results]The results showed that straw mulching significantly increased the stocks of SOC,POC,and MAOC(P＜0.05).As the amount of straw mulch increased,the stock levels of these carbon fractions rose gradually,peaking at a mulch amount of 300 g·m-2,with values of 22.1 g·m-2 for SOC,8.1 g·m-2 for POC,and 14.0 g.m-2 for MAOC.Beyond this amount,further increases in straw mulch did not significantly affect these stock levels.Additionally,straw mulching also significantly improved the physicochemical and biological properties of the soil(P＜0.05).The enhancement of these proper-ties was most pronounced at a straw mulch amount of 300 g·m-2.At this level,the soil water content in-creased to 17.5％,the dissolved organic carbon content reached 164.4 mg·kg-1,the total nitrogen con-tent was 0.86 g·kg-1,the ammonium nitrogen content was 3.6 mg·kg-1,the nitrate nitrogen content was 7.2 mg·kg-1,the available phosphorus content was 6.1 mg·kg-1,the microbial biomass carbon reached 189.8 mg·kg-1,the β-1,4-glucosidase activity was 142.6 μmol g-1 h-1,and the cellulose hydrolase activi-ty was 72.34 μmol g1 h-1.Meanwhile,the soil bulk density decreased to 1.13 g cm-3,the soil temperature decreased to 19.6℃,and the soil pH value decreased to 8.26.Correlation analysis showed that SOC,POC,and MAOC were significantly and negatively correlated with soil bulk density,temperature,and pH,while they were significantly and positively correlated with soil moisture,dissolved organic carbon,total nitrogen,ammonium nitrogen,nitrate nitrogen,available phosphorus,microbial biomass carbon,β-1,4-glucosidase,and cellulose hydrolase activity(P＜0.05).Further analysis indicated that straw mulch-ing mainly increased SOC stocks by increasing POC stocks,with a contribution rate ranging from 55％to 58％.Stepwise regression analysis showed that β-1,4-glucosidase was the key factor affecting SOC and MAOC stocks,while available phosphorus was the key factor affecting POC stocks.[Conclusion]Overall,straw mulching significantly increases SOC,POC,and MAOC stocks,and the enhancement ef-fect increases with the amount of mulch.Once the mulch amount exceeds 300 g·m-2,additional mulch does not significantly raise SOC,POC,and MAOC.Thus,300 g·m-2 is the optimal mulch amount for in-creasing SOC in apple orchards on the Loess Plateau.This measure maximizes the carbon sequestration benefits of straw mulch while it effectively avoids resource waste,providing a scientific basis for the sustainable development of apple orchards.

Abstract:[Objective]The fruit weight of peaches is a quantitative trait influenced by multiple genes.This paper provides a comprehensive summary of the molecular markers associated with fruit weight,which have been identified in previous studies.It also evaluates the breeding value of fruit weight in cultivated varieties in China,focusing exclusively on the additive effects between loci.Furthermore,this study identifies and recommends parental materials that can be utilized to improve existing variet-ies.[Methods]Building on both domestic and international research advancements,this study synthe-sized the molecular markers associated with fruit weight as identified by previous researchers.Utilizing the 574 genome resequencing data generated by our team,we employed Trimmomatic software to en-sure the quality control of the raw sequencing data,resulting in filtered sequences.Subsequently,BWA software facilitated sequence alignment,while GATK software was employed for variant detection,ulti-mately enabling the determination of each variety's genotype.Genotypic effect values were calculated as follows:the allelic effects of SNP loci on traits were estimated by comparing the phenotypic values of different genotypes[homozygous reference(0/0),heterozygous(0/1),and homozygous mutant(1/1)]in pairs.Alleles were classified as positive if there was a significant increase in phenotypic values be-tween the homozygous reference and other genotypes;otherwise,they were classified as negative.Addi-tionally,we screened and recommended parental materials for the improvement of current varieties by incorporating locus effect values.[Results]Drawing upon research advancements both domestically and internationally,this study identified markers with specific chromosomal locations,including SNPs and Indels,ultimately selecting 46 markers from eight research teams.An analysis of marker positions revealed that the numbers of markers on chromosomes 1 through 8 were 5,6,4,9,3,12,2,and 5,re-spectively,indicating a higher concentration of loci on chromosomes 4 and 6.Utilizing genetic varia-tion data from 574 peach cultivars collected in the initial phase of laboratory research,the linkage dis-equilibrium(LD)of the germplasm was calculated.The physical distance at which the LD intensity(r2)decayed to a standard level was used as the threshold for merging loci,resulting in a reduction of loci to 25.Additionally,19 marker sites were identified after excluding 6 markers that were significantly diver-gent from the germplasm.These loci can be utilized to assess their contribution to the trait of fruit weight in natural populations,with the effect values of these 19 loci exhibiting significant heterogene-ity.Among these,three loci(N3,N10,and N19)exhibited strong positive effects,with the N3 locus at the terminus of chromosome 1 showing the highest effect value of 10.86.Conversely,five loci(N11,N13,N15,N16,and N17)demonstrated strong negative effects,with the N15 locus at the apex of chro-mosome 6 having the lowest effect value of--20.06.Neutral effect sites,with values ranging from-1.72 to 1.04,constituted 36.84％of the total.With three superior varieties(Zhongyoupan 7,Zhongyoupan 15,and Huaguang),the breeding values of the parents of Zhongyoupan 7 and Zhongyoupan 15 exhibit-ed minor fluctuations throughout the breeding process;however,the overall trajectory was upward.In contrast,during the breeding of Huaguang,the breeding value for fruit weight showed a linear decline,aligning with the downward trend observed in the actual fruit weight phenotype during the breeding pro-cess.Furthermore,an analysis of the 30 principal varieties currently under cultivation revealed a highly significant positive correlation between the predicted effect values and the actual observed values,with an R2 of 0.467 3(r0.01,28=0.462 8,P=3.125 0E-05).Among these 30 main varieties,24 exhibited nega-tive effects at the N15 locus,which had the highest effect value,and 19 exhibited negative effects at the N13 locus,which had the second highest effect value.Consequently,all these varieties can be hybrid-ized with germplasm(including wild germplasm,local varieties,or other breeding varieties)possessing the mutation site,and the molecular marker-assisted selection can be conducted through genotype identi-fication.Utilizing the identified markers,the parent germplasm with significant improvement potential for key cultivated varieties,such as Changling Zaoyulu,Jinlin 8903,Wanpantao,Jietubai and Baihua,was selected from local varieties.[Conclusion]In conclusion,this study identified and screened 19 markers associated with fruit weight,and their effect values were aggregated.The breeding values of the parent materials and 30 primary varieties were calculated during the cross-breeding process of three different varieties.The results demonstrated a correlation between the breeding values and the observed phenotype of fruit weight,thereby confirming that these markers are applicable in molecular-assisted breeding for enhancing fruit weight,which realized the early prediction of fruit weight phenotype of peach.

Abstract:[Objective]Grape is a perennial twining vine of the genus Vitis in the family Vitaceae.Crossbreeding is a conventional and main method of grape breeding.Crossbreeding can produce favor-able genetic benefits,and the offsprings can have the excellent characteristics of both parents.The devel-opment of modern molecular biology techniques has made it possible to use molecular markers closely related to specific traits for parent selection or pre-selection of hybrid offspring,thereby improving breeding efficiency.The study aimed to develop Kompetitive Allele Specific PCR(KASP)markers for grapevine leaf and fruit traits,and provide technical support for marker-assisted breeding in grapevine.[Methods]Using Shine Muscat(Vitis vinifera × V labrusca)and Suffolk Red(V vinifera×V labrusca)and their 150 hybrid progeny as materials,we collected leaves and mature fruits,and performed whole genome resequencing of PE 150 using the Illumina platform,and analyzed the genome of Shine Muscat and Suffolk Red through population SNP detection,core SNP screening and KASP marker-assisted breeding.The trait association analysis was carried out by combining phenotypic data.The young leaves of Shine Muscat and Suffolk Red and their 150 hybrids were used to extract DNA from the young leaves on the shoots by conventional CTAB method,and the quality and concentration of DNA were detected.The crape leaf samples were collected from July to August in 2023-2024.The leaf length and leaf width were measured by vernier caliper,and the leaf area was calculated.The weight of single fruit was measured by electronic balance,and the transverse and longitudinal diameters of fruit were measured by vernier caliper.The hardness of the fruit was measured by CT-3 texture analyzer,and the central position of the fruit was placed directly below the probe.The contents of total phenols and flavonoids were determined by Cao Jiankang's method.The sugar composition and content in the fruit were determined according to the method of Komatsu et al.by liquid chromatography.Whole-genome resequencing data were processed through quality control,reference genome alignment,variant detec-tion to identify SNP and develop core KASP makers.[Results]The group genome resequencing of Shine Muscat and Suffolk Red and their 150 hybrid offsprings was performed by sequencing platform,and a total of 819 Gb high-quality bases were obtained.Among them,the high-quality bases obtained by Shine Muscat were 10.25 Gb,the high-quality bases obtained by Suffolk Red were 10.02 Gb,and the total number of high-quality bases obtained by 150 hybrids was 799 Gb.The comparison rates for the parents and hybrid offspring were 97.79％,96.79％,and 97.25％,respectively.A total of 432 926 SNPs were identified.Through principal component analysis,the maximum principal component was 10.39％.It can be seen that no principal component can clearly distinguish the hybrid offspring.The SNPS were filtered,and 74 core SNPs were attained.The missing rates of core SNPs ranged from 0.01 to 0.055;most of the minimal allele frequency(mAF)ranged from 0.15 to 0.19;most of polymorphism information content(PIC)ranged from 0.260 to 0.295;and the SNP heterozygosity rate ranged from 0.275 to 0.300.The 19 KASP makers from 43 samples were develop.The heterozygosity rate of 0.295-0.300 was 73.7％,the missing rate of 0.048-0.055 was 52.6％,the genetic diversity indices ranged from 0.250 to 0.287 and PIC ranged from 0.260 to 0.295.The KEGG enrichment analysis for KASP makers revealed that flavone and flavonol biosynthesi was the most significant pathway.The others were fruc-tose and mannose metabolism,pentose and glucuronic acid conversion,and plant-pathogen interaction.These pathways could provide reference for the study of fructose,glucose content and total phenol,fla-vonoid content and other related traits.The phenotypic and physiological indexes of the 11 traits related to the leaves and fruits of the parents and hybrids were analyzed by SPSS software.The results showed that the parents had differences in leaf area,fruit vertical diameter,grain weight,hardness,fructose,glu-cose and other traits.The variation range of its hybrid offspring was large,and the trait separation was obvious.The coefficient of variation of the leaf area was the largest,followed by the total phenol and grain weight,and the lowest was fructose.Through the Shapiro-Wilk test of the traits of the hybrid off-spring,the leaf length and width,fruit grain weight,fructose and glucose all showed normal distribu-tion.The correlation analysis between 43 phenotypic traits and KASP genotypes identified 14 makers associated with the leaf and fruit characteristics.[Conclusion]Through whole-genome resequencing of Shine Muscat,Suffolk Red and their 150 hybrid progenies,a total of 432 926 SNP loci were detected.After filtering based on depth,completeness and genetic parameters,74 core SNP loci were obtained,and 19 KASP markers were successfully developed.Combined with association analysis of the leaf and fruit traits,14 functional markers were screened out,among them 4 were related to the leaf morphology,2 were associated with the fruit size,4 were involved in the fructose/glucose metabolism,and 3 were re-lated to the total phenol/flavonoid synthesis.The KEGG analysis showed that the genes where these markers were located were significantly enriched in the flavonoid and flavonol biosynthesis pathways(P＜0.01),and this would provide molecular targets for the study of the fruit color and quality regula-tion.The KASP markers developed in this study could be used for early trait selection in grape breed-ing.The 14 KASP markers developed in this study could be used for molecular selection of the grape leaf and fruit traits,and the associated pathways such as flavonoid synthesis would provide a theoretical reference for quality breeding.