In this study，by using Ziziphus jujuba‘Dongzao’as a model，the phenological phases of flower development were documented，the process of flower development and nectar secretion was tracked，and the quantity and sugar content of the nectar were assessed under the facility cultivation. The results showed that compared to the open field cultivation，facility cultivation significantly advanced the sprouting stage of jujube floral bud，extended the duration of individual flower blooming and peak flowering periods，and increased both the quantity and sugar content of nectar. Overall，under the facility cultivation，‘Dongzao’exhibited superior in phenological phases，flower development，as well as nectar composition and quantity，compared to those under the traditional open field cultivation.

Sunburn is a common physiological disorder in citrus production，but the underlying mechanism remains largely unknown. The study was carried out at Fenghuang Mountain，Banyue Town，Dangyang City，Hubei Province in 2021. Satsuma mandarin（Citrus unshiu Marc.）and Ponkan（C. reticulata）were used as experimental materials to investigate the difference in sunburn and potential mechanisms by examining peel injury degree，performing cytological observation，measuring antioxidant content and gene expression levels. The results showed that Satsuma mandarin was more susceptible to sunburn than Ponkan. Significant difference in the incidence rates of sunburn was observed between the two varieties，43.12% for Satsuma mandarin and 22.52% for Ponkan. Sunburn seriously influenced the compactness of pericarp cells and resulted in the accumulation of lignin. Satsuma mandarin fruits were found to accumulate greater level of reactive oxygen species（ROS）. In addition，nobiletin，a critical metabolite in the polymethoxyflavone metabolic pathway，was significantly enriched in Ponkan fruit peel. Consistently，transcript levels of CrCHS2，CrCHI and CrFNS，encoding crucial enzymes involved in biosynthesis of flavonoid，and CrOMT2 in the polymethoxyflavone pathway were significantly induced in the sunburnned Ponkan fruit peel. Taken together，these findings indicate that the main reason for the difference in sunburn between Satsuma mandarin and Ponkan is that the latter contains more antioxidant that can effectively decrease the ROS accumulation，thus leading to mitigation of sunburn-derived damage.

Using‘Zhangshugang’pepper suitable for fresh and immature fruits as experimental material the changes of shape，firmness，tissue structure，main nutrients，cell wall substances，capsaicinoids and volatile components of fruit during fruit development were investigated，and the correlation analysis and principal component analysis of quality characteristics was carried out to clarify the key factors affecting the quality. The results showed that the longitudinal diameter，transverse diameter，single fruit weight，flesh thickness，fruit firmness and cuticle thickness of fruit increased gradually from the development of pepper fruits to the colour change stage. The number of pericarp cell layers did not change，and the volume of parenchyma cells increased resulting in the thickening of flesh. The contents of soluble protein showed a‘U-shaped’change with fruit development；soluble sugar and vitamin C showed an overall increasing trend；the total pectin content increased first and then decreased. The content of cellulose and hemicellulose showed a decreasing-rising-decreasing-rising trend，and the content of cellulose and hemicellulose was the lowest at 15 days after flowering. Capsaicinoids content increased rapidly in the early stage of development. A total of 158 volatile constituents were detected during pepper fruit development，dominated by terpenes，esters，heterocyclic compounds，hydrocarbons，ketones，alcohols，and aldehydes，with an increase in terpenes，esters，hydrocarbons，ketones，and aldehydes， from 10 to 25 d after flowering. Therefore，low fruit firmness，thin cuticle，moderate spiciness，low content of cellulose and total pectin content，and relatively high volatile componentsmay be the main reasons for the excellent taste of fresh and immature pepper. In addition，the results of principal component analysis showed that soluble protein content was also one of the important factors affecting the quality of ‘Zhangshugang’ pepper.

Discovering natural triploids from diploid seedling offspring is an effective mehod to cultivate new seedless citrus cultivar. In this study，the small plump seeds of Orah were germinated and sowed，and the ploidy of seedling offsprings was identified by morphological screening，flow cytometry and chromosome counting. A total of 98 triploid lines of Orah seedlings were obtained. Two pairs of SSR primers with polymorphism between the female parent and its candidate male parent were used to analyze the hybrid origin of triploid progenies. It was found that only the amplification product of Orah mandarin could be detected in the triploid progenies. Further genetic analysis was performed using 36 pairs of S-RNase primers. Results showed that the S genotype S₁₁/S_M of Orah mandarin was detected in all triploid progenies，and the S genotype S₂₂ of the candidate male parent Shatangju occurred in two lines，presumed that these two lines were triploid progenies produced by the hybridization of Orah and Shatangju，and were formed by fertilization of 2n female gametes. The remaining lines might be autotriploids produced by selfing of Orah. Compared with the diploid seedlings，the triploid seedlings of the same age grew slowly，the internodes became shorter，the dwarfing was obvious，the main roots were short and thick，the fibrous roots were less，the leaves were dark green and thicker. Under the same cultivation and management conditions，the expression of multiple stress response related genes（CitCOMT，CitGRAS，CitERF4 and CitERF9）in the leaves of allotriploid plants was significantly up-regulated compared with diploid and autotriploid plants.

In order to improve the selection efficiency of melon materials with different pulp firmness types. The crispy melon inbred line 20S11 and the soft melon inbred line 20S75 were used as parents to construct F₂ and BC₁F₁ populations，analyzed the fruit pulp firmness trait is inherited by a single gene，and crispy is dominant relative to soft. A mixed pool of extreme fruit flesh hardness traits was constructed based on the F₂ segregation population. Using whole genome sequencing combined with map based cloning technology，the pulp firmness gene CmPf1 was located in a region of approximately 54.71 kb on chromosome 10. Through resequencing analysis，it was found that the gene MELO3C012216（CmGATL3） encoding GATL3（galacturonosyltransferase-like 3）in 20S75 had a termination codon mutation located at the 567th base（C-G）of the coding region，leading to early termination of protein translation and resulting in complete deletion of the transferase protein domain. The expression pattern analysis of CmGATL3 using qRT-PCR showed that the expression level in crispy melon 20S11 was significantly higher than that in soft melon 20S75. Based on the above mutation sites，PF-KASP molecular marker was developed and performed genotype detection on 56 melon inbred line materials. Among them，the crisp materials were C︰C type，and the soft materials were G︰G type，and the markers were codominance. Further utilizing PF-KASP for genotype identification of F₂ population，compared with the results of pulp firmness phenotype identification，the accuracy reached 100%.

The late ripening new chestnut cultivar‘Yanbao’was selected from the wild seedlings in Yanshan region. It has excellent characteristics such as high yield，high quality，big nut and good color. The average nut weight is 9.0 g，with purplish brown and glossy shell. The density of pubescence is sparse and the tendon lines are inapparent. The nut is ellipse with uniform size and milk yellow flesh，which stir-fry delicate，sweet and waxy. The nuts mature period is late September，with yield per tree 6.73 kg，equivalent to 5 604 kg · hm^-2.‘Yanbao’has strong drought and cold resistance，and appropriate to be planted in hilly region of Mount Yanshan，the appropriate pollination cultivars are‘Yanshan Zaofeng’‘Yanlong’and‘Yanli’.

‘Longjiao 13’is a new hot pepper F₁ hybrid cultivar，acquired with lines 1474 and 1439 as female and male parent respectively. The fruit is horn shape with wrinkle，28.0 cm in length，3.1 cm in width，0.27 cm in pulp thickness and 66 g in weight. The fruit has a green color，wrinkled surface，spicy taste，and good commercial value. Average yield is 75 000 kg · hm^-2 in facilities.‘Longjiao 13’is resistance to TMV and Phytophthora blight and it is suitable for planting in facilities and open fields in northwest China.

In order to clarify the fruit quality and aroma substance content characteristics of‘Merlot’grape from different producing areas in Hexi Corridor，this study analyzed the climate data，soil nutrients，fruit quality and aroma substance components of Jiayuguan，Zhangye and Wuwei producing areas for three consecutive years. The results showed that the soil of the three regions was generally lack of organic matter，and the content of organic matter was below grade 4（lack）. The pH value of soil was from 7.72 to 8.23，belonging to neutral to alkaline soil. The contents of nitrogen，phosphorus and potassium in the surface soil are relatively rich，and the contents of iron，copper and manganese in the soil at different depths in Wuwei are relatively high. The monthly effective accumulated temperature and diurnal temperature difference in Zhangye from April to September are significantly higher than those in other regions，and the rainfall in Wuwei region is the largest. The glucose content in the fruit quality of the three producing areas was Zhangye > Jiayuguan > Wuwei，and the sucrose content was the opposite，and the content of tartaric acid，citric acid and ascorbic acid in Wuwei was higher than that in the other two producing areas. The total content of aroma compounds in fruit quality in Jiayuguan in 2018 and 2019 was higher than that in the other two producing areas. Environmental factors such as temperature and precipitation were significantly correlated with fruit sugar and acid content，and mineral elements such as calcium，manganese，copper and iron in soil were also significantly correlated with fruit sugar and acid content. Therefore，it can be considered that the differences of aroma substances in different habitats are the result of the combined action of environmental factors and soil nutrition.

CRISPR/Cas9 is the immune defense system in bacteria and archaea. In 1987，a special repeat interval sequence was firstly discovered in Escherichia coli. Later，this repeat interval sequence was also found in more than 20 bacteria and archaea. In 2002，this special sequence was officially named as CRISPR. Subsequently，a series of studies using CRISPR/Cas9 technology for gene editing were carried out. CRISPR/Cas9 technology is the third generation gene editing technology，following ZFNs（zinc finger nucleases）technology and TALENs（transfer activator like effector nucleases）technology. This system has the advantages of simple operation design，high mutation efficiency，low cost，and has been successively applied in many horticultural plants such as citrus，grape，banana，strawberry，cucumber，and potato. This article reviews the principles and research progress of CRISPR/Cas9 technology，discusses the developmental history of various editors，including single base editor，double base editor，and guided editor，introduces the application of CRISPR/Cas9 technology in horticultural plants，and finally proposes the remaining problems and future prospects of CRISPR/Cas9 technology.

Tomato brown rugose fruit virus（ToBRFV）belongs to the genus of Tobamovirus and the family of Virgaviridae，which is an RNA virus. It can infect plants from various families and genera，including tomato，posing a serious threat to agricultural production. It was first discovered in Israel in 2014 and subsequently spread to many countries and regions around the world. In April 2021，the virus was as a quarantine virus in China. In this article，the genome structure，host range，symptoms，mode of transmission，detection methods，host resistance and defense measures of the virus were summarized，in order to provide reference for the fight against ToBRFV.

The fresh-eating sweet corn‘Tiancui 710’，was selected from hybrids of DH3534（female parent）and ET1003（male parent）. Its grain is yellow，the reducing sugar content ranges from 4.65% to 5.10%，the soluble sugar content ranges from 12.92% to 15.12%. It is sweet and fragrant.The average fresh ear yield of the cultivar rang from 15 100 to 15 290 kg · hm^-2. It is suitable for fresh corn cultivation in areas south of the Huai River in Anhui and Jiangsu，Shanghai，Zhejiang，Jiangxi，Fujian，Guangdong，Guangxi，Hainan，Sichuan，Chongqing，Guizhou，Hunan，Hubei，and the hilly，flat，and low mountain areas in central Yunnan.

‘Yangguang 1’（Citrus reticulata Blanco），developed by a crossing of‘Hongmeiren’（Ehime Kashi 28）as seed parent with‘Haruka’as pollen parent，is a monoembryonic and sterile line showing seedless and male-aborted. It is vigorous with high fruit-setting rate. The leaves have smooth surface with acute apex. The fruits are smooth and high flat-round in shape. The pulp is light orange in colour，crispy and tender. Single fruit weights 240-270 g in weight with 13.0%-15.0% total soluble solids，0.65% titratable acidity and 435.0 mg · L^-1 Vitamin C. In Chongqing，it matures in late November. The fruits are tolerant to storage and transportation，but tend to be suffered from high fruit cracking rate in the open field，so this cultivar is suitable for cultivation in greenhouse facilities. With annual yield of 26 300-27 500 kg · hm^-2，the major production regions include the dry-hot river valleys of Yunnan，plain/hilly area in Sichuan and western Hunan region.

In order to explore the function of SlWRKY46 in response to low temperature stress，the CDS sequence of SlWRKY46 cloned from tomato‘Micro-Tom’leaves was analyzed. The result showed that SlWRKY46 belonged to Ⅱa group of WRKY family and encoded 253 amino acids. SlWRKY46 was localized in the nucleus by subcellular localization analysis. SlWRKY46 had no transcriptional activation activity in yeast. SlWRKY46 could form homologous dimers by yeast two-hybrid yeast（Y2H）. The results of real-time fluorescence quantitative PCR（qRT-PCR）showed that the expressions of SlWRKY46 were significantly induced by low temperature and abscisic acid（ABA）. The GUS staining of SlWRKY46 promoter transgenic tomato also cloud be induced by low temperature and ABA. The overexpressed SlWRKY46 tomato lines had higher cold tolerance compared with wild-type. The overexpressed SlWRKY46 tomato lines exhibited lower reactive oxygen species accumulation and malondialdehyde levels，and higher antioxidant enzyme activities and proline accumulation compared with wild-type under low temperature treatment. The expression levels of genes related to antioxidant enzyme and ABA showed significant differences between overexpressed SlWRKY46 tomato lines and wild-type under low temperature treatment. Taken together，these results indicated that SlWRKY46 positively regulated the cold tolerance of tomato by antioxidant enzyme and ABA pathways.

To investigate the effect of water-soluble β-glucans on the fruit quality of‘Italian Riesling’grape，aqueous solutions of β-glucans at different doses（0，300，400 and 500 mg ∙ L^-1）were sprayed at 53 and 63 days after flowering. Grape berries were randomly collected at the 60，67，and 95 days after flowering respectively to investigate the dynamic changes in basic physicochemical parameters，glycosidase activities and volatile compounds during fruits ripening. Results showed that the application of exogenous water-soluble β-glucans improved the content of pH，soluble solids，total sugar，total polyphenols，total free amino acids and yeast assimilable nitrogen，especially in 400 mg ∙ L^-1 water-soluble β-glucans treated mature grapes，and was 7.02%，18.99%，18.75%，8.55%，35.96% and 17.05% higher than those observed in the control sample. Meanwhile，β-glucans spraying on grapevines significantly increased the activity of β-D-glucosidase，disaccharidases，as well as the contents and types of volatile compounds in grape skins collected at different sampling periods（P < 0.05）. Compared to the control，the activity of β-D-glucosidase，the total activity of three disaccharidases and concentrations of aroma compounds in grapes that received 400 mg ∙ L^-1 β-glucans increased by 38.01%，28.72% and 31.18%，respectively. Except for n-hexanal and 2-hexenal，the content of other marker differential volatile compounds showed a positive correlation with glycosidase activity. Additionally，grapes treated with 400 mg ∙ L^-1 β-glucans presented an advantage of development of fruity，flowery and sweet flavour. Taken together，applying 400 mg ∙ L^-1 water-soluble β-glucans to the whole vine canopy had positive effects on berry quality of Italian Riesling grape.

In order to investigate the effects of exogenous γ-aminobutyric acid（GABA）on the photosynthetic pigment and sugar content of leaves and fruit flavor quality in wine grape‘Cabernet Gernischt’，GABA solution with different concentrations（5，10，15 and 20 mmol · L^-1）was sprayed on the leaves at the flowering stage，fruit setting stage，enlargement stage and veraison stage，and distilled water was sprayed as the control. Photosynthetic pigment and sugar content of leaves at different stages and fruit flavor quality at the ripened stage were determined. Flavor quality of fruits was comprehensively evaluated and analyzed by using the PEN3 electronic nose non-destructive detection technology and gas chromatography-mass spectrometry（GC-MS）technology combined with cluster analysis，linear discriminant analysis（LDA），principal component analysis（PCA）and correlation analysis. The results showed that GABA treatment increased the contents of chlorophyll，carotenoids，soluble sugar and starch of the leaves of‘Cabernet Gernischt’grape and improved the flavor quality of the fruit. Notably，the total chlorophyll content in 10 mmol · L^-1 GABA-treated leaves was significantly higher than that of the control at different developmental stages. After treatment with 10 mmol · L^-1 GABA，the soluble sugar content of ripened grape fruits increased by 9% compared to the control group，while the levels of oxalic acid and tartaric acid showed respective increments of 121% and 108%. Compared with the control，GABA treatment increased the variety and content of fruit aroma volatiles. The aroma substances in fruits treated with different concentrations of GABA were similar in types，but showed significant difference in contents. The aroma profiles obtained by electronic nose analysis were basically consistent with that by GC-MS analysis. Among the different concentrations used in this study，10 mmol · L^-1 GABA treatment had the highest content of volatile aroma substances，as well as the higher sensitivity response values for most sensors. PCA and LDA analysis showed that the electronic nose detection results could better distinguish the flavor of‘Cabernet Gernischt’grape fruits treated with different concentrations of GABA. The correlation analysis showed that the contents of soluble sugar，starch in leaves and fruit sugars and organic acids have correlation with the formation of aroma substances in fruit. In summary，exogenous GABA treatment improved the flavor quality of the fruit by enhancing the contents of photosynthetic pigments，soluble sugar and starch in leaves and prompting the accumulation of sugars and organic acids and aroma volatiles in grape fruits；10 mmol · L^-1 was chosen as the optimum concentration of GABA.

In order to study the response of GH3.17 gene to salt stress in strawberry，the evolutionary relationship and physicochemical properties of FaGH3.17 were analysed using bioinformatics，and the gene was cloned and subsequently subcellularly localised in tobacco and heterologously overexpressed in Arabidopsis to verify its function in salt stress. The results showed that FaGH3.17 is an acidic and unstable hydrophobic，non-secretory protein，and the analysis of the evolutionary relationship of species revealed that FaGH3.17 is the closest relative to Potentilla anserina. Subcellular localisation in tobacco revealed that FaGH3.17 was mainly localised in the nucleus and cell membrane. Heterologously overexpression analysis in Arabidopsis thaliana revealed that under salt stress，the conductivity，MDA and H₂O₂ content were higher than those of wild-type plants，which were elevated by 15.43%，42.97%，and 18.86%，respectively，whereas the Pro content，POD，SOD，and CAT activities were significantly lower than those of the wild-type plants，which were reduced by 13.28%，15.42%，14.22%，19.87%，respectively. And the relative expression of salt-responsive genes were all significantly reduced. It was shown that heterologous overexpression of FaGH3.17 significantly reduced the antioxidant enzyme activities and osmoregulatory substance contents in Arabidopsis，which predicts that GH3.17 may attenuate the salt tolerance of plants.

In order to explore the effects of biological-organic fertilizer combined with specialized fertilizer on soil nutrients，soil microbial diversity and yield in vineyards，this study selected the‘Shine Muscat’grape under protected cultivation as the research object，and conventional fertilization treatment as the control treatment. The research results showed that the soil pH，available phosphorus，available potassium，and exchangeable calcium or magnesium contents under the biological-organic fertilizer combined with specialized fertilizer and specialized water-soluble fertilizer treatment were significantly increased（P < 0.05）compared with the control treatment. The value of soil bacterial diversity Chao1 index，Shannon index，and total OUT on showed a significant increase，but the soil fungal diversity Chao1 index and Shannon index had no significant changes. The results of Illumina MiSeq high-throughput sequencing analysis showed that soil bacterial communities can be classified into 40 phyla，108 classes，240 orders，326 families，and 595 genera，while soil fungal communities can be classified into 13 phyla，32 classes，71 orders，126 families，and 172 genera. Compared with control treatment，biological-organic fertilizer combined with specialized fertilizer and specialized water-soluble fertilizer treatments at the bacterial phyla level，the relative abundance of Actinobacteria increased by 80.33%，and the bacterial classes level，the relative abundance of α-Proteobacteria and Actinobacteria increased by 29.62% and 108.56%，respectively. At the fungi phyla level，the relative abundance of Ascomycota increased by 4.48%，and at the fungi classes level，Sordariomycetes increased by 10.42%，but Eurotiomycetes and Dothideomycetes decreased by 26.38% and 29.42%. Redundancy analysis（RDA）found that at the phyla level，the explanation rates of environmental factors for soil bacterial and fungal communities change were 64.21% and 56.91% respectively. Soil pH，available potassium，and exchangeable calcium or magnesium had a significant impact on the structure of soil microbial communities in vineyards. Compared to the control treatment，the yield and soluble solid content increased by 25.91% and 5.61% under the biological-organic fertilizer combined with specialized fertilizer and specialized water-soluble fertilizer treatment，respectively.

In order to optimize the virus elimination system of grape plantlets in vitro，research on virus elimination was carried out using the‘Shine Muscat’grape plantlets in vitro，which have been detected carrying five viruses including grapevine fabavirus（GFabV），grapevine rupestris stem pitting associated virus（GRSPaV），grapevine Pinot gris virus（GPGV），grapevine leafroll-associated virus-3 （GLRaV-3），and grapevine virus E（GVE）. The effects on virus elimination regarding heat treatment ways and duration，as well as plant materials（shoot tip or axillary bud）used for inoculation after heat treatment were studied. The results showed that the heat treatment of 38 ℃/light 8 h and 32 ℃/ dark 8 h in turn generated the highest survival rate and virus elimination efficiency，followed by the treatment of 38 ℃/light 16 h and 32 ℃/ dark 8 h in turn and constant 38 ℃（light 16 h + dark 8 h）. Then，about 1.5 mm long shoot tips or the first or the second axillary buds under the shoot tips were cut from the plantlets cultured under the heat treatment of 38 ℃/light 8 h and 32 ℃/ dark 8 h in turn for 10，15，20，25，30，and 40 days，respectively，for inoculation. The survival rate of the shoot tips was higher than that of the axillary buds. The new plantlets were detected for the viruses，and virus-free plantlets were obtained from all kinds of the materials. The virus elimination rate was 52.38% when the heat treatment duration was 10 d，and reached 100% when that was 25 d or 30 d. With the further increased duration，the survival rate of the inoculated shoot tips and the axillary buds decreased. The duration of 25 d was recommended.

To investigate the roles of magnesium transporters（MGTs）in magnesium transportation，the genome-wide identification of peach（Prunus persica）MGTs（PpMGTs）was performed and their effects in exogenous magnesium application on peach tree were studied. A total of eight PpMGTs，which were unevenly distributed in four chromosomes（Chr1，Chr3，Chr6 and Chr8），were identified based on protein homology searches and conserved domain analyses. System evolution analysis results suggested that plant MGTs could be grouped into five different clades which show quantitative differences in species-specific MGTs. PpMGTs had 4-13 exons，ten conserved motifs in protein sequence，and diverse cis-elements of stress response，transcriptional regulation，circadian rhythm，phytohormone response and developmental growth in their upstream promoters. All PpMGTs were transcribed in flowers，fruits，leaves and roots with their unique tissue specific expression pattern. The distinct transcriptional changes of PpMGTs could be observed after exogenous magnesium spraying. Differentially expressed genes found before and after exogenous magnesium application were discrepant in peach leaves and peels，but some of them were commonly involved in the photosynthesis pathway. The transcriptional profile and correlation analysis results suggested that expressional changes of light-harvesting chlorophyll a/b protein complex genes were positively corelated with transcriptional levels of PpMGT4，PpMGT6 and PpMGT8. Heterologous expression of PpMGT4，PpMGT6 and PpMGT8 were able to rescue growth defects of magnesium transport mutant MM281（Salmonella typhimurium mutant），suggesting these three proteins were serving important magnesium transport functions. Thus，the results from sequence characteristics，expressional profiles and exogenous magnesium application showed that PpMGTs had potential functional diversity and synergistic effects in magnesium transport and utilization. The expressional changes of PpMGT4，PpMGT6 and PpMGT8 may associate with exogenous magnesium intake and magnesium utilization.

Tomato with highly significant differences in fruit cracking rate were used as the materials to analyze the expression differences of the SlPL（Solyc03g111690）gene，which was further functionally validated using genetic transformation. The results showed that the expression of SlPL was significantly higher in crack-susceptible tomato‘NT189’than in crack-resistant tomato‘NT91’；The expression of SlPL in tomato fruit was significantly higher than that in other organs such as roots，stems，leaves and flowers，and the expression was higher in the break ripen and red ripen stages of the fruit. Fruit cracking was further induced by irrigation and ABA treatments，and it was found that the expression of SlPL was overall significantly higher in the fruit of crack-susceptible materials than that of crack-resistant ones in the same treatment period. SlPL overexpression（OEPL）and knockout（pl）lines were then obtained by genetic transformation. OEPL was more susceptible to fruit cracking and had significantly lower fruit firmness and pl had higher fruit firmness than the wild type. OEPL fruit had significantly lower pro-pectin content than the wild type，and significantly higher water-soluble pectin content than the wild type，while pl fruit had significantly higher pro-pectin and total pectin content than the wild type. Pectin cleavage enzyme activity was significantly higher in OEPL fruits than in wild type，and pectin cleavage enzyme activity was significantly lower in pl fruits than in wild type. Gene expression analysis revealed that the relative expression of cell wall metabolism-related genes SlPG2，SlPME2.1，SlCel2，SlGH9C5，and ethylene synthesis pathway-related genes SlACS4 and SlACO1 was significantly higher in OEPL fruits than in wild type，and the opposite was true for pl fruits. pl fruits showed a significantly higher relative expression of the ethylene-responsive factor SlERF2 than in wild type. Observations of the pericarp microstructure revealed that the cells of the epidermal layer and thin-walled cells were more sparsely arranged in OEPL compared with wild type，and those cells were tightly arranged in pl.