Genetic & Breeding·Germplasm Resources·Molecular Biology

• Transcription Factors VlWRKY14 and VlTCP5 Respond to Exogenous CPPU and Regulate the Expression of VlIPT12 in Grape
• ZHAO Yaru, WANG Leilei, KONG Guanzhuo, LI Hong, ZHENG Jintao, YUE Yihan, SHI Qiaofang, ZHAO Xiaochun, YU Yihe
• Acta Horticulturae Sinica. 2025, 52(10): 2567-2581. DOI:10.16420/j.issn.0513-353x.2024-0761
• Abstract ( 85 ) HTML ( 50 ) PDF (5704KB) ( 50 ) 　　　

• Treatment with the cytokinin CPPU[forchlorfenuron，N-（2-chloro-4-pyridinyl）-N- phenylurea]significantly improves the fruit setting rate in grapevines，but the underlying molecular mechanisms remain unclear. To elucidate the expression of the isopentenyl transferase gene VlIPT12 after CPPU treatment and the molecular mechanism of its regulation by specific transcription factors，in this study，the VlIPT12 was cloned from‘Kyoho’grapes，and bioinformatics analysis，expression characteristics，and transcriptional regulation analysis were performed. The results showed that the full length of the VlIPT12 was 984 bp，containing a conserved ATP/ADP binding site（P-loop motif）specific to the IPT family and localizing in the nucleus. The expression level of the VlIPT12 gene was the highest in young fruits，followed by that in flowers and tendrils，and was the lowest in leaves. After the grape inflorescences were treated with CPPU，the expression level of VlIPT12 gene was significantly lower than that of the control. The VlIPT12 promoter responded to the treatments of salicylic acid and methyl jasmonate. VlWRKY14 and VlTCP5，as the key transcription factors of VlIPT12，had the same expression pattern as VlIPT12 after CPPU treatment and could bind to the key sites（P1，P2，P4）of the VlIPT12 promoter to promote its expression. In conclusion，after the grape inflorescences were treated with CPPU，the expression level of VlIPT12 decreased，and the transcription factors VlWRKY14 and VlTCP5 could bind to the key sites of the VlIPT12 promoter to positively regulate the expression of VlIPT12 in young fruits.

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• Characterization of Loquat bHLH Gene Family and Functional Analysis of EjbHLH104 on Flowering Regulation in Triploid Loquat
• XIA Yan, HU Ruoqian, YI Guangquan, SUN Hongwen, HUANG Shuxin, CHI Zhuoheng, SHI Min, LIANG Guolu, JING Danlong, GUO Qigao
• Acta Horticulturae Sinica. 2025, 52(10): 2582-2596. DOI:10.16420/j.issn.0513-353x.2024-0790
• Abstract ( 52 ) HTML ( 25 ) PDF (1309KB) ( 25 ) 　　　

• A total of 169 EjbHLH gene family members were identified from loquat genome，and were classified into 22 subfamilies. Then，the cDNA sequence of EjbHLH104，a member of the bHLH gene family，was isolated using RT-PCR from the flower buds of triploid loquat，and it was significantly increased in flower buds of early flowering triploid loquat‘Wuhe Zaoyu’. The coding sequence of EjbHLH104 was 675 bp，encoding 224 amino acids. Protein sequence alignment and phylogenetic tree analysis showed that EjbHLH104 has the conserved bHLH domain and is highly similar to MdbHLH104 of Malus × domestica and PbbHLH104 of Pyrus bretschneideri，which are clustered into the same branch of eurosidsⅠbHLH104 lineage. Subcellular localization analysis showed that the localization of EjbHLH104 protein was in the nucleus，suggesting it has subcellular localization characteristics of bHLH transcription factor. In early and late flowering cultivars of diploid and triploid loquats，the qRT-PCR analysis showed that expression levels of EjbHLH104 were higher at the stages of flower bud differentiation and floret differentiation and reached the highest at full bloom stage in the early flowering cultivars of triploid loquats. However，EjbHLH104 expression level was reached the highest at the development stage of floret differentiation in the early flowering cultivars of diploid loquat. Compared with the wild Arabidopsis thaliana，flowering time observation of EjbHLH104 transgenic Arabidopsis showed that overexpression of EjbHLH104 gene significantly exhibited early flowering，suggesting EjbHLH104 could promote flowering.

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• Development and Application of Insertion-Deletion（InDel）Markers in Papaya（Carica papaya）Based on Whole Genome Re-Sequencing Data
• YANG Min, HE Han, ZHOU Chenping, KUANG Ruibin, LIU Chuanhe, WU Xiaming, XU Ze, WEI Yuerong
• Acta Horticulturae Sinica. 2025, 52(10): 2597-2612. DOI:10.16420/j.issn.0513-353x.2024-0850
• Abstract ( 57 ) HTML ( 26 ) PDF (3525KB) ( 26 ) 　　　

• InDel（insertion/deletion）loci were mined using resequencing data of 5 papaya germplasm resources，and efficient and applicable molecular markers were designed based on these loci. After strict screening，3 635 InDel loci that are easy to detect by gel electrophoresis，with a length of more than 30 bp and showing high polymorphism were successfully identified. 360 loci evenly distributed across the genome were selected to design primers. After preliminary screening with 6 papaya materials，it was found that 355 pairs of primers could successfully amplify the target products，among which 271 pairs showed significant polymorphism，accounting for 75.3% of the total number of candidate primers. 72 pairs of highly polymorphic markers were selected for genotyping and genetic diversity analysis of 47 papayagermplasms，and a total of 145 allelic loci were detected. The polymorphism information content （PIC）of the markers ranged from 0.0408 to 0.4523，with an average of 0.3041；the gene diversity index varied from 0.1030 to 0.8735，with an average of 0.5660. Through cluster analysis，the 47 papaya accessions were divided into 4 groups. In addition，based on the amplification results of 20 pairs of highly polymorphic core InDel markers，combined with 4 key agronomic traits（flower color，single fruit weight，fruit shape，and flesh color），molecular identities of different papaya germplasms were constructed. Meanwhile，two InDel markers that can reflect the differences between parents were selected to identify the authenticity of 24 F₁ hybrid progenies of GT1-5 בHuangjinzhong’papaya，and 11 true hybrids were successfully confirmed.

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• Interaction Analysis of the Pattern Recognition Receptor FLS2-BAK1 in Pepper and Nicotiana benthmiana
• JIN Jinghao, SU Chao, CHEN Yi, SUN Shichao, CHEN Xinxin, CHEN Xiaoren
• Acta Horticulturae Sinica. 2025, 52(10): 2613-2624. DOI:10.16420/j.issn.0513-353x.2024-0461
• Abstract ( 38 ) HTML ( 14 ) PDF (3438KB) ( 14 ) 　　　

• Through interacting with co-receptor kinase，plant receptor kinases play an important role in the activating of immune response. The interaction mechanism of pattern recognition receptor module FLS2-BAK1 in Arabidopsis has been revealed. While the interaction relationship between the function domain of FLS2 and BAK1 in pepper and tobacco is still unclear. In the present study，CaFLS2-CaBAK1 and NbFLS2-NbBAK1 were cloned from Capsicum annuum and Nicotiana benthamiana respectively. Then structure character analysis，subcellular location and interaction relationship of them were analyzed. Research results showed that CaFLS2，CaBAK1，NbFLS2s and NbBAK1 contain the character domain of LRR-type receptor kinase and NbFLS2 may has different type coding sequence. All of the receptor kinases are localized on the cell membrane. The BiFC experiment results indicated that there is an interaction relationship between the extracellular domain，intracellular domain of CaFLS2 and CaBAK1，and also NbFLS2s and NbBAK1. What’s more，the interaction between the full-length protein of NbFLS2s and NbBAK1 was detected with BiFC assay，and their co-expression could induce ROS production in N. benthamiana. These results not only increase the knowledge of FLS2-BAK1 module in pepper and N. benthamiana，but also provide a basis for revealing the immunity signal pathway medicated by receptor kinase in Solanaceae crops.

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• Construction of Yeast Library and Identification of the BrrCDPK Gene Family of PSY Potential Interacting Proteins in Turnip
• BIAN Shuanling, DENG Changrong, FAN Luze, WU Yanxun, REN Yanjing
• Acta Horticulturae Sinica. 2025, 52(10): 2625-2641. DOI:10.16420/j.issn.0513-353x.2024-0833
• Abstract ( 40 ) HTML ( 17 ) PDF (5425KB) ( 17 ) 　　　

• Different tissues of yellow turnip W25 and white turnip W21 were used as plant materials to construct cDNA yeast library of turnip，whose library capacity was 1.5 × 10⁷ CFU and average length of insert frangment was greater than 1 000 bp. A total of 18 positive interacting proteins were obtained by hybridizing the constructed bait vector pGBKT7-PSY with the cDNA library. Then，a robust interaction between the candidate protein CDPK8 and PSY was confirmed by rigorous yeast two-hybrid and bimolecular fluorescence complementation（BiFC）experiments. The interacting protein CDPK was selected for gene family analysis，and a total of 50 CDPK genes（named BrrCDPK1-BrrCDPK50）members with STKc_CAMK protein kinase and 2 domains of EF-hand were identified. Structural analysis revealed that the number of amino acids encoded by CDPK genes ranged from 411 to 660，with an averagetheoretical pI of 8.79. No number and structural differences of conserved motifs among each CDPK proteins were found，and all proteins contained motif 1，motif 2，motif 3 and motif 6. Chromosome location showed that the distribution of BrrCDPKs on each chromosome was nonrandom. Phylogenetic analysis revealed that BrrCDPKs and AtCDPKs were clustered into different groups，indicating that CDPK gene duplication during evolution existed some species specificity. Gene expression profiling identified that 14 CDPK genes were highly expressed in yellow turnips than that in white turnip.

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• Development and Application of KASP Marker for the Ms Locus of Male Sterility Restoration Gene in Onion
• YANG Yanyan, LI Yanwei, WANG Zhenbao, CAO Degao, XU Xin, LIU Bingjiang
• Acta Horticulturae Sinica. 2025, 52(10): 2642-2654. DOI:10.16420/j.issn.0513-353x.2025-0172
• Abstract ( 40 ) HTML ( 19 ) PDF (5844KB) ( 19 ) 　　　

• To improve the selection efficiency of the onion male sterility restorer gene Ms locus and accelerate the breeding process，this study developed a kompetitive allele-specific PCR（KASP）marker suitable for high-throughput detection based on SNP variation sites in the allelic sequence of the AcSKP1 gene. The results showed that the KASP marker KMs4 effectively classified the genotypes（MsMs，Msms，msms）of the Ms locus in an F₂ segregating population into three distinct categories，and the genotypes at the Ms locus in the BC₁ segregating population into two categories（Msms，msms）. Moreover，the genotyping results fully consistent with those obtained using the AcSKP1 marker. The versatility of the KMs4 marker was further confirmed across materials with known genotypes from diverse genetic backgrounds. Fertility trait evaluation was conducted on collected onion open-pollinated populations，from which different breeding lines were screened and selected for hybrid breeding. In summary，the KMs4 marker is a molecular marker tightly linked to the onion male sterility restorer gene Ms locus，enabling high-throughput genotyping of large-scale breeding materials.

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• Functional Analysis of SoCHR35 in the Biosynthesis of Ocimene in Syringa oblata
• WANG Jinxuan, NI Ying, MENG Xin, LENG Zhuo, MA Bo, LENG Pingsheng, WU Jing, HU Zenghui
• Acta Horticulturae Sinica. 2025, 52(10): 2655-2665. DOI:10.16420/j.issn.0513-353x.2024-0817
• Abstract ( 35 ) HTML ( 11 ) PDF (4329KB) ( 11 ) 　　　

• In order to investigate the role of SoCHR35（Chromatin remodeling complex ATPase 35），a member of RNA-mediated DNA methylation pathway，in the biosynthesis of lilac floral substance—ocimene，the SoCHR35 gene was cloned and analyzed，including bioinformatics，spatiotemporal expression pattern，functional characterization，and subcellular localization. The results showed that the total length of the CDS sequence of SoCHR35 was 2 073 bp，encoding for 690 amino acids. The protein had the typical SNF2 conserved domains of DEXDc and HELICc，and was clustered with CHR35 of Perilla frutescens and Sesamum indicum. The spatiotemporal expression analysis showed that with the flower development the expression level of SoCHR35 first decreased and then increased，which was negatively correlated with the release of floral scents. After transiently overexpressing SoCHR35 in lilac petals，the release amount of ocimene was significantly reduced，while transiently silencing of SoCHR35 lead to a remarkable increase in the release amount of ocimene. Through subcellular localization，SoCHR35 was found to be located in chloroplasts，which was same to the expression position of SoTPS2，a ocimene synthase gene. Moreover，the transient silencing of SoCHR35 resulted in a significant enhancement of SoTPS2 expression in petals. These results indicated that SoCHR35 negatively regulated the biosynthesis of ocimene in lilac petals to impact the floral scent release，which may result from a direct or indirect regulation of SoTPS2.

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• Pollen Chromosome Doubling of Ehretia macrophylla Induced by High Temperature
• ZHANG Yu, GENG Xining, PENG Chaofeng, LI Meiyu, QI Shuaizheng, YANG Yingjun, CHENG Shiping
• Acta Horticulturae Sinica. 2025, 52(10): 2666-2676. DOI:10.16420/j.issn.0513-353x.2024-0788
• Abstract ( 32 ) HTML ( 13 ) PDF (2794KB) ( 13 ) 　　　

• In present study，flower buds of Ehretia macrophylla were selected as the experimental material. The meiotic process of microspores of E. macrophylla was investigated. The optimal conditions for inducing pollen chromosome doubling by high-temperature exposure were identified and in order to establish technique for high temperature-induced pollen chromosome doubling in E. macrophylla. The anthers of E. macrophyllawere dropped with acetocarmine solution and placed under a microscope to observe the process of meiosis. On the basis of clarifying the meiosis process of pollen mother cells flower buds in meiotic prophase Ⅰ to high temperatures of 38，40 and 42 ℃ with 4 hours treatment. The findings indicated that the meiosis process of pollen mother cells in E. macrophylla mostly concentrated when the longitudinal diameter of flower buds was 2.0-4.0 mm and there was obvious asynchrony. When the longitudinal diameter of the flower buds was between 2.0-3.0 mm，76.5% of the flower buds of E. macrophylla were in the premeiotic stage Ⅰ，when the longitudinal diameter of the flower buds was between 3.6-4.0 mm，meiosis basically completed，indicating that there was a significant correlation between the longitudinal diameter of the flower buds and meiosis of pollen mother cells. When the longitudinal diameter of the flower bud is between 2.6-3.0 mm in which pollen mother cells were at the packytene to diplotene stage，a high rate of 2n pollen（15.14%）were obtained after 4 h treatment at 42 ℃.

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• Screening and Analysis of Phyllostachys edulis PheNAC4 Interacting Proteins by Yeast Two-Hybrid System
• XIE Lihua, YAO Pengqiang, LIU Jiaxue, WANG Zhe, ZHU Nannan, CHENG Shiping, CHENG Zhanchao
• Acta Horticulturae Sinica. 2025, 52(10): 2677-2690. DOI:10.16420/j.issn.0513-353x.2024-0755
• Abstract ( 36 ) HTML ( 12 ) PDF (4648KB) ( 12 ) 　　　

• Previous experiments have shown that the PheNAC4 gene of Phyllostachys edulis（moso bamboo）is down-regulated after salt stress，and its protein sequence is highly similar to other stress-related NAC genes. Overexpression of the PheNAC4 gene reduces the tolerance of transgenic Arabidopsis thaliana to salt stress. To further investigate its regulatory mechanism，PheNAC4 was used as bait to screen for interacting proteins in this study. The results indicated that PheNAC4 is non-toxic to yeast Y2H Gold cells，although it exhibits self-activation activity in the yeast two-hybrid assay. The self-activation activity of PheNAC4 can be inhibited by adding 1 000 ng · L^-1 Aureobasidin A（AbA）inhibitor. In the yeast two-hybrid experiment，36 candidate proteins interacting with PheNAC4 were identified through screening and sequence analysis. These candidate proteins are likely involved in the response of moso bamboo to drought and salt stress，as well as in senescence regulation. To validate these interactions，two stress-related candidate proteins，PheR40C1 and PheF3HL，were selected for further investigation. The yeast two-hybrid assay and bimolecular fluorescence complementation（BiFC）experiments were conducted. These experiments confirmed that PheNAC4 forms heterodimers with PheR40C1 and PheF3HL in both yeast and plant cells. Analysis of the expression patterns of the PheR40C1 and PheF3HL genes after salt stress showed that PheR40C1 was down-regulated in the first 12 hour，exhibiting a similar expression pattern to that of the PheNAC4 gene. In contrast，PheF3HL displayed an opposite expression pattern compared to PheNAC4. These results suggest that PheNAC4 may play a crucial role in the salt stress response of moso bamboo through interactions with PheR40C1 and PheF3HL.

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• Investigation of Ancient Tea Germplasm Resources and Their Characters from Timian Town，Guangzhou
• QIN Dandan, FANG Kaixing, WANG Qiushuang, WANG Qing, PAN Chendong, NI Erdong, FENG Shaofang, WU Zhanhong, WU Hualing
• Acta Horticulturae Sinica. 2025, 52(10): 2691-2702. DOI:10.16420/j.issn.0513-353x.2024-0873
• Abstract ( 35 ) HTML ( 10 ) PDF (6031KB) ( 10 ) 　　　

• This study conducted a systematic investigation into their ecological environment，biological characteristics，biochemical composition，and processing suitability of ancient tea trees Tiamian Town in Huadu District，Guangzhou. The study reveals that most tea germplasm resources exist in the form of clustered communities，which are relatively close to each other. The major tea tree resources include Maoyecha（Camellia.sinensis var. ptilophylla Chang），Qinggui Daye[C. sinensis（L.）O. Kuntze]，Guangzhou Xiaoye[C. sinensis（L.）O. Kuntze]，and Xianghua Caoguocha（C. suaveolens），among which Maoyecha is the most abundant and well-preserved. Among the 150 representative ancient tea trees surveyed，the majority exhibited an arborous or small-arborous growth habit. Maoyecha displayed distinct morphological characteristics，including a tall and slender canopy，densely pubescent buds and leaves，extensive branching，and leathery leaves. Leaf morphology varied significantly，ranging from extra-large to small leaves，with considerable diversity in venation，shape，and serration patterns. The young shoots exhibited significant variations in coloration and pubescence，while most resources showed weak flowering and fruit-setting ability. Cross-sectional analysis of leaves revealed substantial variation in the thickness of the upper and lower epidermis，palisade tissue，and spongy tissue. Biochemical analysis indicated high and unique levels of tea polyphenols，alkaloids，and catechins，with Maoyecha exhibiting particularly high levels of theobromine and non-epicatechins. The processing suitability assessment demonstrated that Maoyecha is suitable for producing white tea，black tea，and yellow tea，whereas Guangzhou Xiaoye and Qinggui Daye are more suitable for black tea and green tea production.

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• Identification and Expression Analysis of CBF Gene Family of Artemisia argyi
• LIU Lu, WANG Meng, ZHENG Xiaomei, WANG Keqing, MIAO Ruyi, ZANG Qiaolu
• Acta Horticulturae Sinica. 2025, 52(10): 2703-2712. DOI:10.16420/j.issn.0513-353x.2024-0801
• Abstract ( 59 ) HTML ( 19 ) PDF (2493KB) ( 19 ) 　　　

• CBF（C-repeat binding factor）gene family is categorized as the transcriptional activators and exerts an important role in response to abiotic stresses such as low temperature. In order to investigate the CBF gene family members involved in temperature response of Artemisia argyi，17 AaCBF genes of A. argyi were identified and analyzed by bioinformatics in this study. It was found that the amino acid length of the encoded protein ranged from 131-222 aa，with an average isoelectric point of 6.08. Most of the AaCBF proteins were localized in the nucleus. The 16 genes were unevenly distributed on 5 chromosomes，with the highest distribution on chromosomes 8 and 16. AaCBF08 was not localized to chromosomes. Based on the phylogenetic tree analysis，the gene family could be divided into 4 subfamilies，with members of the A. argyi gene family distributed across 3 of these subfamilies. All AaCBF gene family members contained Motif 1，Motif 5 and Motif 7，and conserved domains，demonstrating a high level of conservation. In addition，none of 17 genes contained introns. qRT-PCR results showed that six candidate AaCBF genes were significantly differentially expressed across different tissues of A. argyi. Under high-temperature treatment，the expression levels of the four candidate AaCBF genes gradually increased and reached the highest expression at 12 hours. Notably，the expression levels of AaCBF04 and AaCBF16 initially increased，subsequently decreased，and increased again at 12 hours and reached its highest level. Under low-temperature treatment，the expression levels of five candidate AaCBF genes first increased and then decreased，with the highest expression at three hours. In contrast，AaCBF15 increased again at 12 hours and reached its highest level.

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Cultivation·Physiology & Biochemistry

• Effect of Gibberellin on Wizened Flower Buds Formation of Pyrus pyrifolia Cultivar‘Sucui 1’During the Growing Season
• LI Hui, KAN Jialiang, LI Xiaogang, WANG Zhonghua, LIN Jing, YANG Qingsong
• Acta Horticulturae Sinica. 2025, 52(10): 2713-2726. DOI:10.16420/j.issn.0513-353x.2024-0810
• Abstract ( 40 ) HTML ( 17 ) PDF (6974KB) ( 17 ) 　　　

• To explore the relationship between flower buds wizening and gibberellin，the flower bud from Pyrus pyrifolia cultivar‘Sucui 1’was selected as the experimental material in this study. The gibberellin contents of‘Sucui 1’pear were compared between normal flower buds and wizened flower buds，and the expression of genes related to the gibberellin synthesis pathway once flower buds wizening were analyzed. Then the effect of applying gibberellin inhibitor paclobutrazol to control flower buds wizening was studied in the growing season. The results showed that there was significant difference in gibberellin contents between normal flower buds and wizened flower buds. The contents of GA₁，GA₃，GA₄ and GA₇ in wizened flower buds were 1.25-2.87 times of those in normal flower buds. Transcriptome analysis showed that，comparing with normal flower buds，wizened flower buds had 3 290 differentially expressed genes in which 2 046 were up-regulated and 1 244 were down-regulated. qRT-PCR confirmed the up-regulated expression of GA2ox1（gibberellin 2-oxidas 1），GA2ox2 （gibberellin 2-oxidas 2），GA3ox（gibberellin 3-oxidas），GA20ox （gibberellin 20-oxidas）and GID1（gibberellin insensitive Dwarf1）genes in wizened flower buds. Meanwhile，GAI（gibberrellic acid insensitive），GASA3/4/6/14（Arabidopsis gibberrellic acid stimulating protein 3，4，6 and 14），GID2（gibberellin Insensitive Dwarf2）and KAO（ent-kaurenoic acid monooxygenase）were down-regulated in wizened flower buds. And their expression information was consistent with the results of transcriptome sequencing. After the application of polybulobuzole，the gibberellin contents in axillary flower buds of annual branches reduced and the proportion of wizened flower buds in‘Sucui 1’decreased in mid-September. The content of gibberellin was significantly positively correlated with the proportion of wizened flower buds（r = 0.94）. Furthermore，the transcription levels of GA2ox1/2，GA3ox，GA20ox，GAI，GASA3/4/6/14，GID1/2 and KAO in‘Sucui 1’flower bud were affected by applying polybulobuzole，which took part in the synthesis and metabolism of gibberellin. Spraying paclobutrazol can inhibit the transcription levels of GA2ox1/2，GA3ox，GA20ox，GASA3/4/6/14，GID1，and KAO in the axillary flower buds of‘Sucui 1’pear，but promote the expression of GAI and GID2，furthermore regulate the synthesis and metabolism of gibberellin. The research results indicate that an abnormal increase in gibberellin during the growing season can lead to wizened flower buds in pear. Spraying paclobutrazol would regulate the expression of genes related to the gibberellin synthesis pathway，inhibit it synthesis， and relief the wizened degree of pear flower buds.

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• Effects of Citrus Chlorotic Awarf-Associated Virus on the Tissue Structure and Enzyme Activity of Green Pomelo and Lemon
• ZHOU Jun, FANG Shujie, GUO Xueyang, ZHANG Xiaonan, XU Zitong, ZHOU Bing, YI Long
• Acta Horticulturae Sinica. 2025, 52(10): 2727-2736. DOI:10.16420/j.issn.0513-353x.2024-0784
• Abstract ( 32 ) HTML ( 16 ) PDF (6013KB) ( 16 ) 　　　

• To elucidate the histological characteristics and enzymatic activities associated with symptom development in citrus induced by citrus chlorotic dwarf-associated viru（CCDaV），‘Ruby’green pomelo seedlings on trifoliate orange rootstock and‘Eureka’lemon seedlings were inoculated with CCDaV. The symptomatic manifestations，histological structures，chloroplast ultrastructure，and enzyme activities were investigated. The results demonstrated that CCDaV induced pronounced leaf malformation and chlorosis in both cultivars，accompanied by abnormal development in the phloem and xylem tissues of leaf veins. Symptoms appeared earlier and were more severe in‘Ruby’，exhibiting vein clearing. Chloroplasts in ‘Ruby’displayed enlarged starch granules with significant gaps between the granules and thylakoid lamellae，leading to chloroplast swelling，deformation，and disintegration of the chloroplast envelope. The activities of SOD，POD，and CAT increased extremely significantly in‘Ruby’leaves，while MDA content and the activities of SOD，CAT，and APX increased significantly in‘Eureka’. In conclusion，CCDaV infection causes abnormal development in citrus vein tissues，chloroplast swelling and deformation，and membrane damage，inducing severe leaf malformation and chlorosis，thereby impairing plant health，growth，and development.

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• Effects of Different Nitrogen Concentration on the Locule Number in Tomato Fruit
• SUN Meihua, SUN Huixian, ZHAO Yanli, LI Jing, TIAN Linlin, MIAO Yanxiu, BAI Longqiang, HOU Leiping, ZHANG Yi, LI Tianlai
• Acta Horticulturae Sinica. 2025, 52(10): 2737-2747. DOI:10.16420/j.issn.0513-353x.2024-0867
• Abstract ( 43 ) HTML ( 14 ) PDF (1533KB) ( 14 ) 　　　

• Tomato seedlings were treated with nutrient solutions containing varying nitrogen concentrations. The nutrient content，enzyme activity，endogenous hormone levels，and gene expression changes in the shoot tips were analyzed to explore the mechanisms by which different nitrogen supply levels regulate the locule number of tomato fruit. The results indicate that increasing nitrogen nutrition levels accelerate tomato flower bud differentiation，increase the locule number of fruits and the content of soluble protein，starch，sucrose，and soluble sugar and enhances POD，NR，and PPO enzyme activities in the seedling stem tips. Closely related to the locule number of fruits is soluble protein，soluble sugar content and POD，NR and PPO activities. Furthermore，higher nitrogen nutrition levels lead to increased levels of cytokinins，gibberellins，and jasmonic acid in the stem tips. The transcriptome analysis revealed differentially expressed genes，including peroxidase genes PRX44-like，PRX3-like，and PRX66，alongside gibberellin synthesis gene GA2ox2 and cytokinin synthesis genes TLOG1 and CKX2. Based on the observed physiological changes，it is speculated that enhancing nitrogen nutrition levels during the seedling stage may regulate the expression of PRX44-like and GA2ox2 genes，thereby increasing POD enzyme activity and gibberellin content，ultimately influencing the locule number of tomato fruit.

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• Effects of Cold Circulation Induction on Photosynthesis and Yield of Cucumber in Solar-Greenhouse
• ZHAO Meng, AI Xizhen, QI Chengzheng, BI Huangai, FENG Yiqing, ZHANG Xiaowei
• Acta Horticulturae Sinica. 2025, 52(10): 2748-2760. DOI:10.16420/j.issn.0513-353x.2024-0868
• Abstract ( 31 ) HTML ( 20 ) PDF (2031KB) ( 20 ) 　　　

• Cold-induced stress memory，as a flexible behavior in response to environmental changes，plays an important role in plant acclimation to adverse conditions. To elucidate the regulating mechanism of cold circulation-induced stress memory on the environmental adaptability of photosynthesis in cucumber in solar greenhouse.‘Jinyou 35’cucumber plants were used as experimental materials，and were treated in an artificial climate chamber. There were four treatments： no cold induction treatment（C0R0），single cold induction（C1R1：24 h treatment at a day/night temperature of 8 ℃/8 ℃ followed by a recovery period of 48 h at 25 ℃/18 ℃），repeated cold circulation induction twice（C2R2：same conditions as C1R1，cycle twice），and repeated cold circulation induction three times（C3R3：same conditions as C1R1 treatment，cycle three times）. Subsequently，the seedlings were exposed to chilling stress condition（8 ℃/5 ℃）. The C0R0 treatment at normal temperature（25 ℃/18 ℃）was used as the control（CK）. The relevant indexes of photosynthesis were measured after 48-72 h of low temperature. The seedlings exhibiting the most favorable cold circulation-induced effect and C0R0 treatments were then selected and cultivated within a solar greenhouse to investigate the effect of cold-induce memory on the photosynthetic rate（P_n），photochemical efficiency，growth and yield. The results showed that C1R1-，C2R2- and C3R3-treated seedlings exhibited significantly higher P_n，stomatal conductance（G_s），transpiration rate（T_r），as well as activities and mRNA expressions of ribulose-1,5-bisphosphate carboxylase（RuBPCase）and Rubisco activase（RCA）. Additionally，the C1R1，C2R2 and C3R3 treatments revealed an increase in maximum photochemical efficiency of PSⅡ（F_v/F_m），actual photochemical effect of PSⅡ（Φ_PSII），electron transfer rate of PSⅡ[ETR(II)]，quantum efficiency of PSⅡ photochemistry[Y(Ⅱ)]，electron transfer rate of PSⅠ[ETR(Ⅰ)]and quantum efficiency of PSⅠ photochemistry[Y(Ⅰ)]. Whereas，there were either lower or no significant differences observed in intercellular CO₂ concentration（C_i），compared with the C0R0 treatment under chilling stress. Among the four treatments，C2R2-treated plants exhibited the greatest increase in P_n，G_s，T_r，F_v/F_m，Φ_PSⅡ，activity and mRNA expression of RuBPCase and RCA，and decrease in C_i，while C1R1 treated seedlings showed the least changes in these parameters. The P_n，F_v/F_m and Φ_PSⅡ of C2R2 treated cucumber grown in the solar greenhouse were significantly higher than those of the C0R0 at low temperatures. These findings indicate that the cold circulation induction maintain higher photosynthetic carbon assimilation capacity and photosystem activity，alleviate the damage to photosynthetic apparatus caused by chilling stress，thereby improve the growth and development of cucumber. The yield of C2R2 treatment was 10.25% higher than that of C0R0. The stress memory induced by two cycles of cold circulation in cucumber plants was between 20 and 30 days.

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• Effects of Exogenous Glutathione on Photosynthetic Characteristics of Leaf Lettuce Under High Temperature Stress
• ZHOU Xiaolin, LIN Junxuan, LI Caixia, SUN Meihua, BAI Longqiang, HOU Leiping, MIAO Yanxiu
• Acta Horticulturae Sinica. 2025, 52(10): 2761-2773. DOI:10.16420/j.issn.0513-353x.2024-0876
• Abstract ( 42 ) HTML ( 16 ) PDF (2730KB) ( 16 ) 　　　

• Using leaf lettuce‘Glass lettuce’as the test material，this study analyzes the effects of different temperatures and different concentrations of exogenous glutathione（GSH）on leaf gas exchange parameters，chlorophyll fluorescence parameters，and expression levels of photosynthesis-related genes，investigating the impact of exogenous GSH on the photosynthetic characteristics of leaf lettuce under high-temperature stress. The results showed that high temperature stress（36 ℃/30 ℃）significantly reduced growth，photosynthetic rate（P_n），maximum photochemical efficiency（F_v/F_m），actual photochemical efficiency（Φ_PSII），and leaf pigment content，but significantly increased the non-photochemical quenching coefficient（Φ_NPQ），soluble protein content，and free amino acid content. That is high temperature stress significantly inhibited lettuce growth and reduced leaf photosynthetic efficiency and photosynthetic electron transport chain performance. However，under high temperature stress，foliar application of 0.5 and 1 mmol· L^-1 GSH treatments significantly increased the whole-plant fresh weight，P_n，and Φ_PSII of lettuce，significantly upregulated the expression levels of key genes（psbA，psbB，psbD，psbH，psbK，psbN）encoding PSⅡ reaction center proteins in lettuce leaves. Additionally，the 0.5 mmol · L^-1 GSH treatment significantly increased leaf pigment content and soluble sugar content. Therefore，applying exogenous GSH can effectively alleviate the adverse effects of high temperature stress on the photosynthetic characteristics of lettuce.

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• 3D-Based Analysis of Plant Architecture-Light Interception Correlation in Vegetable Crops
• JU Qingqing, WANG Xiaoli, ZHENG Xiuguo, WANG Quhong, ZHU Huizhi, QIAN Tingting
• Acta Horticulturae Sinica. 2025, 52(10): 2774-2786. DOI:10.16420/j.issn.0513-353x.2024-0802
• Abstract ( 32 ) HTML ( 9 ) PDF (3368KB) ( 9 ) 　　　

• Analyzing the relationship between crop architecture and canopy light interception using efficient parameter acquisition methods is crucial for precision breeding and cultivation research. In this study，3D digital technology was employed to acquire architectural parameters of 30 cultivars across five vegetable crops. The inter-varietal differences in stem length，petiole length，leaf length，leaf width，and leaf angle were extracted and analyzed. A 3D population model was constructed for each of the five vegetable crops，and canopy light interception calculation were conducted based on the 3D models. Multiple linear regression approach was used to analyze the correlation between architectural parameters and canopy light interception. The analysis results showed that，significant differences in leaf angle were observed among the cultivars of tomato，cucumber，eggplant，and pumpkin. Significant differences in stem length were observed in cucumber cultivars，while stem length and petiole length showed notable differences among pepper cultivars. Canopy light interception calculate revealed significant differences in light interception among the cultivars of tomato，cucumber，eggplant，and pepper. Leaf angle was found to be a key factor affecting light interception in tomato，cucumber，and pepper，with a negative correlation between leaf angle and light interception. Short petioles in cucumber and tomato cultivars were beneficial for light interception，while pepper cultivars with wide-elliptical leaves were favorable for light interception. Compared to traditional methods of obtaining architectural parameters，the 3D digital technology used in this study provides a rapid and visual approach for plant architecture evaluation and analysis.

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Plant Protection

• Molecular Identification and Genetic Variation Analysis of Chilli Veinal Mottle Virus Infecting Taro
• CHEN Yue, ZHENG Xue, DONG Kun, WU Kuo, XIAO Xiangli, LI Yu, ZHANG Jie
• Acta Horticulturae Sinica. 2025, 52(10): 2787-2798. DOI:10.16420/j.issn.0513-353x.2024-0797
• Abstract ( 30 ) HTML ( 7 ) PDF (1895KB) ( 7 ) 　　　

• To clarify the types of viral pathogens infecting taro[Colocasia esculenta（L.）Schott] samples in Yunnan Province，virus testing was conducted on taro samples collected from Fuyuan County，Yunnan Province that exhibited suspected symptoms of viral disease. The research results provide a theoretical basis for virus screening and effective prevention and control of taro plants in the future. PCR and RT-PCR detection of Yunnan taro samples were conducted using universal primers for virus genera such as Begomovirus，Potyvirus，Orthosporovirus and Tobamovirus，as well as specific primers for chilli vein mottle virus. The CP gene sequence of the ChiVMV isolate from Yunnan taro was obtained through cloning and sequencing. By combined the CP genes of other ChiVMV isolates which were published in GenBank，genetic variation and population genetic structure analysis were conducted using bioinformatics software. The ChiVMV CP gene conservation high conservation during the evolutionary process. The identity of nucleotide and amino acid sequences of the CP gene between the Yunnan taro isolate obtained in this study and 29 ChiVMV isolates was 85.13%-99.65% and 90.59%-99.65%，respectively. Phylogenetic analysis and trait association analysis shows that there was a signification between the genetic differentiation of ChiVMV and the geographical origin of its isolates to a certain extent，but not significantly correlated with the species of host plants. Analysis of genetic diversity and population genetic structure indicates that，influenced by geographical factors，all four geographical populations of ChiVMV isolates display high levels of genetic diversity. Genetic drift and gene flow were significant means of genetic variation in ChiVMV populations. This study represents the first report on the natural invasion of ChiVMV into the Araceae plant，taro. The research results enrich the host range and population genetic information of ChiVMV，which is of great significance for monitoring the spread of ChiVMV in China.

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Review

• Research Progress on the Healing Process of Cucumber Grafting and Related Influencing Factors
• LIN Huangfang, CHENG Saichuan, LIN Biying, CHEN Yanzhen, YE Huilan, SHAO Qingqing, LIN Honghui, ZHAI Tingkai, WANG Kai, SHEN Baoying
• Acta Horticulturae Sinica. 2025, 52(10): 2799-2815. DOI:10.16420/j.issn.0513-353x.2024-0688
• Abstract ( 40 ) HTML ( 13 ) PDF (863KB) ( 13 ) 　　　

• Grafting has been extensively utilized in cucumber production and cultivation，significantly boosting plant stress resistance，yield，and fruit quality. The success rate of grafting and the quality of grafted seedlings are jointly influenced by various factors，including grafting techniques and healing conditions. Clarifying the mechanisms and influencing factors associated with the healing process of cucumber grafting，as well as exploring the application of non-destructive testing techniques in this context，holds considerable significance for optimizing industrialized grafting seedling production systems. Consequently，this paper summarizes the histological，cytological，physiological and biochemical，molecular，and phenotypic omics mechanisms underlying the cucumber grafting healing process. It also reviews the impacts of stock-scion compatibility，grafting methods，seedling age，hormones，nutrients，and environmental factors on the healing process. Additionally，the paper provides insights into cucumber grafting healing mechanisms and production applications from five perspectives：the establishment of non-destructive testing models for cucumber grafting healing，the exploration of exogenous substance application methods，the analysis of the internal mechanisms by which grafting methods affect healing，the functional validation of key genes related to grafting healing，and the influence of environmental factors on the synthesis and transport of endogenous substances in grafted plants. The ultimate goal is to offer a reference for non-destructive testing of grafted cucumber seedlings，optimization of grafting techniques，and precise regulation of healing environments in subsequent production processes.

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• Research Progress on Molecular Regulation Mechanism of Parthenocarpy in Tomato
• ZHANG Guoxin, SONG Jianing, CUI Xia
• Acta Horticulturae Sinica. 2025, 52(10): 2816-2828. DOI:10.16420/j.issn.0513-353x.2025-0030
• Abstract ( 57 ) HTML ( 20 ) PDF (1226KB) ( 20 ) 　　　

• Parthenocarpy is a trait that the ovary develops into fruit without fertilization. Parthenocarpy could alleviate the blossom and fruit dropping caused by adverse conditions in tomato，ensuring the fruit yield. In addition，the seedless fruit is preferred by consumers. Therefore，parthenocarpy has been recognized as an important trait in tomato breeding. Research has shown that phytohormones，particularly auxin and gibberellin，are key factors regulating tomato parthenocarpy. Additionally，sugars，flavonoids，small RNAs，and MADS-box transcription factors are also involved in the regulation of parthenocarpy. Although numerous parthenocarpic tomato resources have been identified，the key regulatory genes have not yet been fully characterized，and the molecular mechanisms remain to be further elucidated. This article reviewed the germplasm resources of parthenocarpic tomato，the key genes regulating parthenocarpy，and the molecular regulation mechanism of parthenocarpy in tomato，providing a reference for better understanding the formation of parthenocarpic fruit in tomato.

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New Cultivars

• A New Rosa Cultivar‘Sichouzhilu’
• MENG Yanqiong, HU Jing, LAN Wei, ZHANG Xiaoxuan, DAI Mengyan, KANG Liyun
• Acta Horticulturae Sinica. 2025, 52(10): 2829-2830. DOI:10.16420/j.issn.0513-353x.2024-0710
• Abstract ( 60 ) HTML ( 24 ) PDF (1143KB) ( 24 ) 　　　

• ‘Sichouzhilu’is a new multi-head shrub rose cultivar，selected from mutation of modern rose cultivar‘Cardinal Hume’. The petals are sword-shaped，radially arranged，double scarlet，and petal in scarlet with 40-50. its flower diameter is 5-7 cm. The flowering period of a single flower is 8-9 days，blooming in clusters，and the flowering period of a single plant is 230 days. The plant height is 40-50 cm. The plant has fewer prickles，strong heat resistance，and strong environmental adaptability. It is suitable for cultivation in the area north of Yangtze River.

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• A New Liquidambar formosana Cultivar‘Huanying’
• CHEN Jiajia, ZHOU Yuhua, SUN Yaya, PAN Jingxia, LIU Yuhua, WU Xiangqian, MO Jiaxing, LI Song, FU Danyang, YU Jian
• Acta Horticulturae Sinica. 2025, 52(10): 2831-2832. DOI:10.16420/j.issn.0513-353x.2024-0400
• Abstract ( 44 ) HTML ( 15 ) PDF (1011KB) ( 15 ) 　　　

• ‘Huanying’is a new ornamental cultivar which is selected from the seedling of Liquidambar formosana. The leaves are medium sized and thick with medium glossiness and complex color. The complex color is at the leaf margin. The main color of young leaves and new leaves respectively is yellow and yellow-green. The main color of the upper surface of mature leaves in summer is yellow-green，while that in autumn is orange-red，the secondary color of leaves is green. The number of lobes is three.‘Huanying’is suitable for planting in the Yangtze River by grafting propagation.

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