Genetic & Breeding·Germplasm Resources·Molecular Biology

• Cloning，Expression and Promoter Activity Analysis of VlRRA1 Gene in Grape
• LI Songqi, LI Xufei, LI Min, LIU Hainan, PEI Maosong, WEI Tonglu, GUO Dalong, YU Yihe
• Acta Horticulturae Sinica. 2023, 50(8): 1609-1621. DOI:10.16420/j.issn.0513-353x.2022-0516
• Abstract ( 556 ) HTML ( 548 ) PDF (1805KB) ( 548 ) 　　　

• The cytokinin response regulator VlRRA1 and its promoter were cloned from‘Kyoho’grape. The expression characteristics of VlRRA1 and the activity of VlRRA1 promoter were analyzed. The results showed that the full-length cDNA of VlRRA1 was 666 bp and encoded 221 amino acids. Conservative domain analysis showed that the gene contained only one phosphoacceptor receiver domain（REC），which belongs to type-A RR genes and can only accept phosphate groups;phylogenetic relationships showed that VlRRA1 was closely related to type-A RR in other species. The yeast self-activation assay illustrates that VlRRA1 has no transcriptional activation activity in agreement with other A-type RR genes and does not have a function similar to that of the B-type RR transcription factor. The results of qRT-PCR showed that VlRRA1 had tissue-specific expression and was mainly expressed in stems，leaves and young fruit，slightly lower expression in inflorescence and ripe fruit，suggesting that VlRRA1 may play an important role in the process of fruit set;exogenous cytokinin forchlorfenuron（CPPU）can promote VlRRA1 expression，while the cytokinin biosynthesis inhibitor lovastatin（LOV）inhibits VlRRA1 transcription. Many elements related to abiotic stress and hormone response were found in VlRRA1 promoter. The results of GUS tissue staining showed that VlRRA1 promoter had promoter activity and could respond to a variety of hormone signals，including three plant hormones related to fruit setting，cytokinin，auxin and gibberellin. These results suggest that VlRRA1 plays an important role in grape fruit setting and young fruit development mediated by cytokinin.

• Figure/Table | References | Related Articles | Metrics

• Study on Genetic Characteristics and Taxonomic Status of Wild Chinese Chestnut Based on Genome Re-sequencing
• NIE Xinghua, ZHANG Yu, LIU Song, YANG Jiabin, HAO Yaqiong, LIU Yang, QIN Ling, XING Yu
• Acta Horticulturae Sinica. 2023, 50(8): 1622-1636. DOI:10.16420/j.issn.0513-353x.2022-0537
• Abstract ( 319 ) HTML ( 183 ) PDF (4453KB) ( 183 ) 　　　

• The cluster analysis of 194 chestnut resources was performed based on SSR molecular markers，and the botanical characteristics of wild chestnut resources were described and compared. Forty-six representative wild and cultivated Chinese chestnut resources were selected for re-sequencing analysis，and phylogenetic and population structure analyses were performed. The clustering results showed that wild Chinese chestnuts and cultivated Chinese chestnuts had a close genetic distance，they were mixed and no obvious division;population structure analysis also further supported that wild Chinese chestnuts and cultivated Chinese chestnuts had the consistent genetic information，revealing cultivated Chinese chestnut may be domesticated from wild Chinese chestnut in situ for a limited time. This study clarified the taxonomic status of wild chestnut，namely：wild Chinese chestnut and cultivated Chinese chestnut belong to the same species. It is clear that the habit of female flower bunching is not a characteristic of wild Chinese chestnut，and a more accurate and up-to-date boundary range of wild Chinese chestnut is proposed.

• Figure/Table | References | Related Articles | Metrics

• Papaya CpWRI3 is Involved in the Regulation of Fatty Acid Accumulation During Fruit Postharvest
• MO Yuxing, ZHOU Yan, LIN Runting, DUO Yongxing, ZHANG Tao, LIU Kaidong
• Acta Horticulturae Sinica. 2023, 50(8): 1637-1648. DOI:10.16420/j.issn.0513-353x.2022-0590
• Abstract ( 238 ) HTML ( 172 ) PDF (3313KB) ( 172 ) 　　　

• A WRI family regulator gene named CpWRI3 was cloned from papaya fruit. Amino acid sequence alignment and evolutionary analyses showed that CpWRI3 has high homology with AtWRI3/4. Transcriptional factor activity analysis showed that CpWRI3 has transcriptional activate function. The expression level of CpWRI3 increased during the fruit ripening process，peaked at eight days after harvested，indicating that CpWRI3 plays an important role in the late stage of fruit ripening. In order to explore the role of CpWRI3 in regulating fatty acid biosynthesis，transient overexpression of CpWRI3 was performed. The data showed that overexpression of CpWRI3 significantly induced the contents of lauric acid，palmitoleic acid and linoleic acid in papaya fruit. In vitro Electrophoretic Mobility Shift Assay（EMSA）confirmed that CpWRI3 could specifically bind to AW-box elements on promoters of downstream target genes CpKAS1 and CpACC1. Using luciferase system，CpWRI3 can induce the promoter activities of CpKAS1 and CpACC1 genes in plants. These results revealed that CpWRI3 may induce the biosynthesis of lauric acid，palmitoleic acid and linoleic acid.

• Figure/Table | References | Related Articles | Metrics

• Genetic Analysis of Chloroplast Genome Characteristics of Potato‘Cooperation 88’Selfing Population
• WANG Rongyan, LI Qing, XU Ling, WANG Qiujie, SONG Yu, MU Changran, TANG Wei, HAO Dahai
• Acta Horticulturae Sinica. 2023, 50(8): 1649-1663. DOI:10.16420/j.issn.0513-353x.2022-0721
• Abstract ( 363 ) HTML ( 108 ) PDF (4241KB) ( 108 ) 　　　

• In order to analyze the chloroplast genome polymorphism and genetic diversity of potato ‘Cooperation 88’at the genome level and to understand the genetic composition and variation of the chloroplast genome of the selfing population of‘Cooperation 88’，this study assembled the chloroplast genomes of‘Cooperation 88’and 30 selfing progenies and comparatively analyzed them with the chloroplasts genomes of 11 other Solanaceae species，Arabidopsis thaliana and Oryza sativa. The results showed that the assembled chloroplast genome of the‘Cooperation 88’was a typical circular structure with a length of 160 323 bp and the GC content of 38.6%，including a total of 29 annotated tRNA genes and 77 protein-coding genes. The size of the chloroplast genome of the 30 selfing progenies ranged from 160 331 bp to 162 120 bp，the number of genes predicted was 95-106，and the GC content was 36.7%-38.6%. Further analysis showed that the chloroplast types of the parent and 30 selfing progeny were all W-type，showing no polymorphism. Both parent and selfing progenies prefer to use codons ending with A/U，and the progenies chloroplasts genomes codon pairs used different frequencies of the four bases，indicating that the relative synonymous codon usage and effective codons in the chloroplast genome of selfing progenies variations in the number of codons and high-frequency codons were caused by random mutation and translational natural selection in the chloroplast genome. In addition，12 repeats existing in the parent were also present in all progenies but four repeats were new appeared in progeny. UPGMA analysis and collinearity analysis also found that the evolutionary level of the Solanum chloroplast genome was highly conserved, but the appearance of repeats and the loss of genes changed the size of the progeny chloroplast genome and increased their genetic diversity.

• Figure/Table | References | Related Articles | Metrics

• Studies on Pollen Micromorphology of Impatiens Plants in Southwest Sichuan
• ZHANG Xi, ZHAO Qiuyan, GU Zhijia, HUANG Haiquan, YAN Bo, HUANG Meijuan
• Acta Horticulturae Sinica. 2023, 50(8): 1664-1678. DOI:10.16420/j.issn.0513-353x.2022-0716
• Abstract ( 250 ) HTML ( 141 ) PDF (7219KB) ( 141 ) 　　　

• In this study，20 species of Impatiens from southwest Sichuan were used as experimental materials，their pollen characteristics，including pollen shapes，outer wall ornamentations and germination furrow types etc.，were observed by scanning electron microscopy，and the analyses of the principal component and cluster were conducted to investigate the pollen morphology and the taxonomic significance. The results showed that pollens of 20 Impatiens species mostly belonged to single four-grooved type（75.00%）and a few single three-grooved type（20.00%），there were significant differences in size，equatorial view，polar view and other traits among pollens of different species. In their polar views，most of them were oval，talar and capsule-shaped，few were triangularly rounded and pentagonal;All the outer wall ornamentations of pollens were reticulate，while there were considerable variation in the sparseness，size of the mesh and the density of the granules within the mesh. On the basis of the comprehensive analysis of above-mentioned characteristics，20 species of Impatiens were classified into seven subtypes. Four principal component factors were identified through principal component analysis，Based on the clustering analysis of pollen morphology，the 20 species can be divided into three major branches，of which the I. soulieana，I. tienchuanensis and I. undulata are clustered into the first branch，I. conchibracteata，I. duclouxii and I. monticola are clustered into the second branch，and I. wilsonii，I. imbecilla and I. rhombifolia are clustered into the third branch.

• Figure/Table | References | Related Articles | Metrics

• Identification，Expression Analysis and Interaction Validation of CsIDM in Tea Plants
• LI Yuteng, CHEN Yao, REN Hengze, LI Congcong, WANG Haoqian, CAO Hongli, YUE Chuan, HAO Xinyuan, WANG Xinchao
• Acta Horticulturae Sinica. 2023, 50(8): 1679-1696. DOI:10.16420/j.issn.0513-353x.2021-1218
• Abstract ( 290 ) HTML ( 192 ) PDF (5155KB) ( 192 ) 　　　

• In this study，using different tea plant genomes as a reference，three CsIDM genes were identified and cloned from Camellia sinensis‘Longjing 43’. CsIDM1，belongs to the histone acetyltransferase family，has a typical HAT conserved domain，and is located in the nucleus. CsIDM2 and CsIDM3，which belong to the heat shock protein family，have typical ACD conserved domains，which are located in the nucleus，cell membrane and cytoplasm. The promoter region of CsIDMs contains a variety of cis-acting elements that respond to environmental signals，including light response，plant hormone response，stress response and plant growth-related elements. Expression analysis showed that CsIDMs expressed higher in flower buds，axillary buds and stems，but lower in fully open flowers，which suggests a certain tissue specificity. CsIDMs were differentially expressed under drought，high temperature and biotic stresses. During the formation and release of dormancy in overwintering buds，the expression of CsIDM1 showed a high-low-high expression pattern in the stages of paradormancy，endodormancy and ecodormancy. It was confirmed that CsIDM2 interacts with CsIDM3 to form a heterodimer by bimolecular fluorescence complementation. CsIDM2 and CsIDM3 interact with CsMBD5 and CsMBD16，respectively. In summary，CsIDMs play an important role in the stress response and bud dormancy removal of tea plants，and may participate in the regulation of methylation through the formation of protein complexes.

• Figure/Table | References | Related Articles | Metrics

Cultivation Physiology & Biochemistry

• Effects and Functional Mechanism of Melatonin on the Growth of Malus hupehensis Seedlings Under Saline-Alkali Stress
• SUN Zhijuan, LIU Wenjie, ZHENG Xiaodong, XI Xiangli, MA Changqing, LIU Xiaoli, WANG Caihong, TIAN Yike
• Acta Horticulturae Sinica. 2023, 50(8): 1697-1710. DOI:10.16420/j.issn.0513-353x.2022-0642
• Abstract ( 400 ) HTML ( 291 ) PDF (2827KB) ( 291 ) 　　　

• To explore the effect of exogenous melatonin on the growth of Malus hupehensis seedlings under saline-alkali stress and its mechanism，M. hupehensis seedlings with 94% apomixis rate were selected as test materials. The control group was irrigated with Hoagland’s nutrient solution（groupⅠ）;The saline-alkali treatment group was irrigated with nutrient solution containing 100 mmol · L^-1 NaHCO₃︰NaCl = 1︰1（groupⅡ）. The group Ⅲ was added with 0.1 mmol · L^-1 melatonin on the basis of groupⅡ. The fresh weight，dry weight，chlorophyll content，photosynthetic rate，mineral element content，antioxidant enzyme activity，osmotic substance content，organic acid content，endogenous hormone content and saline-alkali related gene expression were detected after saline-alkali stress and exogenous melatonin treatment for 15 days. The results showed that application of 0.1 mmol · L^-1 melatonin could significantly enhance the tolerance of M. hupehensis to saline-alkali stress. At first，exogenous melatonin treatment could significantly reduce the wilting rate，and effectively improve the biomass and photosynthesis of M. hupehensis seedlings under salt-alkali stress. Meanwhile，it also increased the content of soluble sugar，soluble protein and proline in seedlings so as to alleviate osmotic stress. In addition，melatonin increased intracellular organic acid content and the expression of AHA family genes to enhanced the saline-alkali tolerance of plants. Moreover，exogenous MT could regulate the expression of Na⁺ transporter genes（MhCHX15 and MhSOS1）and K⁺ transporter genes（MhSKOR，MhNHX1，MhNHX2 and MhNHX4），and enhance the ratio of K⁺/Na⁺ in cytoplasm to maintain ion homeostasis. Melatonin could enhance the activities of POD and CAT and regulate the expressions of antioxidase genes（MhGPX6，MhpoxN1 and MhPER65）to alleviate oxidative damage under saline-alkali stress. Furthermore，exogenous MT could cooperate with gibberellin，auxin，cytokinin and methyl jasmonate responding to saline-alkali stress. In conclusion，exogenous 0.1 mmol · L^-1 melatonin alleviated the damage of saline-alkali stress on M. hupehensis seedlings by regulating ion balance，osmotic substances，antioxidant enzyme activities and coordinating with other endogenous hormones.

• Figure/Table | References | Related Articles | Metrics

• Effects of Brassinolide Treatment on Anthocyanin Synthesis and Quality in Grape Under High Temperature Stress
• DAI Hongjun, WEI Qiang, HE Yan, WANG Yuening, WANG Zhenping
• Acta Horticulturae Sinica. 2023, 50(8): 1711-1722. DOI:10.16420/j.issn.0513-353x.2022-0599
• Abstract ( 300 ) HTML ( 177 ) PDF (1354KB) ( 177 ) 　　　

• To study the effects of 2,4-Epibrassinolide（EBR）on anthocyanin synthesis and berry quality under high temperature stress，Vitis vinifera L.‘Cabernet Sauvignon’were used as the material. Before veraison，grapevines were sprayed with EBR and conducted the heat stress experiments，which simulated by the infrared radiator. Results indicated that the anthocyanin contents were reduced and the expression levels of the anthocyanin synthesis genes such as VvCHS，VvDFR，VvLDOX，and VvMybA1 were down-regulated after heat stress. At the beginning of veraison，compared with the control，the berry coloring rate was reduced by 17.80% after the high-temperature treatment. EBR treatments increased the contents of anthocyanin and soluble sugar in grape berry. The content of anthocyanins in high temperature with EBR treatment was increased by 21.65% compared with only the high temperature group at 77 d after anthesis. At the late ripening stage，the gene expression levels of VvCHS and VvLDOX in high temperature with EBR were 3.27 and 2.21 time folds of those in the high temperature group. Further analysis showed that the content of anthocyanins was significant positively correlated with the transcription level of VvMybA1 under the high temperature + EBR treatment. Moreover，there is a positive correlation relationship between sugar and anthocyanin. In conclusion，the treatment with EBR could increase anthocyanin content，improve berry coloring，promote sugar and total phenols accumulation，and effectively alleviate the effect of high temperature on berry quality in‘Cabernet Sauvignon’.

• Figure/Table | References | Related Articles | Metrics

• Effects of Different Color Bags on Anthocyanin Accumulation in‘Cabernet Sauvignon’Grape Skin
• WANG Wen, ZHANG Kenan, FANG Mofei, DING Siyue, WANG Xuefei, XI Zhumei
• Acta Horticulturae Sinica. 2023, 50(8): 1723-1738. DOI:10.16420/j.issn.0513-353x.2022-0618
• Abstract ( 219 ) HTML ( 150 ) PDF (2767KB) ( 150 ) 　　　

• ‘Cabernet Sauvignon’grape were used in this study and bagged with the white，red，green and blue fruit paper bags before veraison，respectively. The fruit clusters with no bagging were served as the control. The changes of different colors of fruit bags on the light intensity，light transmittance，temperature，fruit quality，individual anthocyanin，enzyme activities and the gene expressions related to anthocyanin accumulation of‘Cabernet Sauvignon’were measured and analyzed，but there was no difference in the temperature inside the red，green and blue bags. The results showed that the bag color has selective transmittance of the light wavelengths. Light intensity and temperature in the bagging treatments were significantly lower than those in the control. Bagging treatments delayed the grape growth，ripening and variation，but the reducing sugar，soluble solids and total anthocyanins contents significantly increased in the blue，red and green bag treatments at harvest，while the blue bag presented the most obvious improvement. The blue，green and red bags increased acetylated anthocyanins contents in grape skin at harvest，while white bag decreased acylated anthocyanin content. In addition，blue，red and green bag treatments significantly increased the enzymes activities of F3′H and DFR at harvest in grape skin，and the up-regulated expressions of anthocyanin synthesis genes，modification genes and transport genes，and correlation analysis results showed that transport of acylated and non-acylated anthocyanins is different. In conclusion，blue and red bags are beneficial to anthocyanin biosynthesis in grape skin，and the blue bag is better，which can be used in viticulture production.

• Figure/Table | References | Related Articles | Metrics

• Effects of Light Duration and Intensity on Yield Formation of‘Shine- Muscat’Grape
• CAO Xiongjun, HAN Jiayu, CHENG Guo, WANG Bo, MA Guangren, LIN Ling, TAN Zongkun, HUANG Qiumi, CHEN Xiao, CHEN Fuyi, SHI Xiaofang, PAN Fengping, BAI Xianjin
• Acta Horticulturae Sinica. 2023, 50(8): 1739-1746. DOI:10.16420/j.issn.0513-353x.2022-0669
• Abstract ( 593 ) HTML ( 176 ) PDF (1636KB) ( 176 ) 　　　

• To explore the relationship between duration or intensity of sunlight and the yield of grape harvest. The light durations and intensities recorded in the summer fruit growing season with those provided by meteorological department were analyzed. Light saturation point and light compensation point of leaves of‘Shine-Muscat’grape during different phonological stages，and the effects of light duration and intensity on net photosynthetic rate and yield of summer fruit of‘Shine-Muscat’grape were analyzed. The results showed that the total light duration recorded by the meteorological station based on direct sunlight was significantly lower than that recorded in the vineyard and did not fully include the light duration corresponding to the light intensity that is available for grape production. Light intensity significantly affected the net photosynthetic rate of‘Shine-Muscat’grape leaves. The light compensation point and light saturation point of leaves of‘Shine-Muscat’grape varied in different developmental stages. The light compensation point of leaves ranged from 22.43 to 49.77 μmol · m^-2 · s^-1，and the light saturation point of leaves ranged from 1 108.07 to 1 303.01 μmol · m^-2 · s^-1. The formation of grape yield is more closely related to the sunshine hours above the light intensity at the light compensation point，and under the light hours above the light compensation point of 1 524.1 h（2018）and 1 579.8 h（2019），the yield of grapes was 13 701.9 and 17 774.9 kg · hm^-2 respectively，and the average soluble solids was more than 17 Brix°. Therefore，suggested that in grape production and quality evaluation，the effects of light hours and light intensity in grape growth and development cycle should be comprehensively considered based on the light saturation point and light compensation point of variety leaves.

• Figure/Table | References | Related Articles | Metrics

• Cell Wall Material Metabolism and the Response to High Temperature and Water Deficiency Stresses in Pericarp are Associated with Fruit Cracking of‘Duwei’Pummelo
• LU Yanqing, LIN Yanjin, LU Xinkun
• Acta Horticulturae Sinica. 2023, 50(8): 1747-1768. DOI:10.16420/j.issn.0513-353x.2022-0653
• Abstract ( 625 ) HTML ( 122 ) PDF (1405KB) ( 122 ) 　　　

• In this study，the pericarp surrounding the blossom end of normal and cracked fruits（three degrees of fruit cracking）from the‘Duwei’pummelo cultivar were used for high throughput RNA sequencing. Some differentially expressed genes are potentially associated with fruit cracking. Galacturonosyltransferase（catalyzing homogalacturonan synthesis）and arabinogalactan protein （maintaining cell wall structure）genes were significantly down-regulated，however，genes （polygalacturonase，pectate lyase）involved in the pectin degradation pathway were significantly up regulated in cracked pericarp compared to the un-cracked pericarp. The changes in the expression of these genes may link to a decrease in mechanical strength of the cell wall，consequently inducing fruit cracking. A gene for 3-ketoacyl-CoA synthase（participating long chain lipid acid synthesis）was 5-6 times in un-cracked pericarp compared to cracked pericarp，suggesting that the decrease in transcript level of the gene may lead to a lower capacity of pericarp to suppress transpiration，ultimately，may lead to water deficiency stress，cell death，and microcrack formation in pericarp. Genes related to high temperature or water deficiency（dehydration-responsive element-binding protein，calcineurin B-like-interacting protein kinase，WRKY30，WRKY33，and WRKY40）were significantly down regulated in cracked pericarp，indicating the possible association of high temperature and water deficiency with fruit cracking.

• Figure/Table | References | Related Articles | Metrics

• Research of Jasmonic Acid Antagonize Ethylene to Delay the Flower Senescence of Oncidium hybridum
• OUYANG Xuanyue, ZENG Sixian, YU Yunyi, WANG Qin, LI Xinyue, YUE Yuechong, YU Rangcai, FAN Yanping
• Acta Horticulturae Sinica. 2023, 50(8): 1769-1778. DOI:10.16420/j.issn.0513-353x.2022-0732
• Abstract ( 196 ) HTML ( 77 ) PDF (1635KB) ( 77 ) 　　　

• In this study，in order to explore the role of ethylene and jasmonic acid in the senescence of Oncidium hybridum ‘Honey Angle’ flowers，endogenous ethylene release rate，jasmonic acid content and senescence after anther cap shedding was investigated. In additon，senescence，endogenous ethylene release and the expression of OhACO1 and OhACO2（ethylene synthesis key genes）after methyl jasmonate and its inhibitors acetylsalicylic acid treatment were also observed. The results showed that anther cap shedding treatment could accelerate senescence of‘Honey Angle’flowers. The endogenous ethylene release rate had reached 168.23 nL · g^-1 · h^-1 after 1 d of anther cap shedding treatment while the control had not yet released. Meanwhile，the endogenous jasmonic acid（JA）content in both treatment at 1 d was significantly higher than that at 0 d，but the content in the anther cap shedding treatment was 57.86% lower than that in the control. Moreover，exogenous methyl jasmonate treatment could significantly inhibited the senescence of flowers and reduced the expression of OhACO1 and OhACO2，while its inhibitors could promoted senescence and increased the expression of OhACO1 and OhACO2. These results indicated that JA could affect ethylene release by inhibiting ethylene synthesis，thereby delaying the senescence induced by anther cap shedding of O. hybridum‘Honey Angle’flowers.

• Figure/Table | References | Related Articles | Metrics

Plant Protection

• Effects of Air Humidity and Soil Water Content Coupling on Tomato Gray Mold
• ZHOU Jie, LI Tianzhu, LIU Ruyi, LI Chenhao, YUAN Zenan, LI Jianming
• Acta Horticulturae Sinica. 2023, 50(8): 1779-1792. DOI:10.16420/j.issn.0513-353x.2022-0418
• Abstract ( 238 ) HTML ( 147 ) PDF (3991KB) ( 147 ) 　　　

• In this study，‘Jinpeng 14-6’tomato cultivar was used as the material，and total six treatments according to two air relative humidity levels（high humidity：80%-95%;low humidity：65%-80%）and three soil relative water content levels（low water content：60%-70%;middle water content：70%-80%;high water content：80%-90%）were set out to investigate their effects on the development of tomato gray mold. The results showed that the tomato gray mold appears earlier and developed more severely and faster in the high humidity conditions than in the low humidity ones;the disease severity under high humidity conditions was as follows：high water content > middle water content > low water content;under low humidity conditions，the disease severity developed slower in middle water content treatment. In the low humidity middle soil water content treatment，the appearance of Botrytis cinerea hyphae was seven days later than the high humidity high soil water content treatment and the damage of the mesophyll cells occurred milder and later. In the early stage of gray mold（one day after B. cinerea inoculation），the thickness of every leaf tissue structures（except the upper and lower epidermis）displayed an escalating trend with an increase of soil relative water content;in the late stage of gray mold（5-10 days after inoculation），under high humidity conditions，the thickness of every leaf tissue structures were significantly lower in high soil water content treatment than other treatments and under low humidity conditions，they were larger in middle soil water content treatment compared with others. With the development of B. cinerea infection，the content of reactive oxygen species and the activity of antioxidant enzymes were relatively more active. In the high humidity conditions，the photosystemⅡ（PSⅡ）maximum photochemical efficiency F_v/F_m and fruit quality were significantly lower than treatments under low humidity conditions. The highest yield was acquired in low humidity middle soil water content treatment and the lowest one was acquired in high humidity high soil water content. The impact of tomato gray mold on the yields under the treatments were air relative humidity > soil relative water content > interactions between them. The low humidity middle soil water content conditions in the tomato cultivation facilities to some extent inhibited the B. cinerea infection，delayed the disease appearance，reduced the disease severity and the impact of the disease on tomato fruit quality and yields.

• Figure/Table | References | Related Articles | Metrics

• Identification of Virus Disease Types of Melon Planting in Jiashi County of Xinjiang
• WANG Dong, MAIMAITIAIZEZI · Muhetaer, LIU Yanquan, DILIDAERKEZI · Wulamu
• Acta Horticulturae Sinica. 2023, 50(8): 1793-1802. DOI:10.16420/j.issn.0513-353x.2022-0543
• Abstract ( 229 ) HTML ( 101 ) PDF (2698KB) ( 101 ) 　　　

• In 2019 and 2021,12 towns in Jiashi county of Xinjiang were investigated and sampled for muskmelon（Jiashi-melon）virus disease. Watermelon mosaic virus（WMV），cucumber mosaic virus（CMV），zucchini yellow mosaic virus（ZYMV），cucumber green mottle mosaic virus（CGMMV），cucurbit aphid-borne yellows virus（CABYV），and melon aphid-borne yellows virus（MABYV）were identified by two-step RT-PCR protocol. In addition，the genome of WMV isolates was analyzed. The results showed that the virus disease is more common in the Jiashi-melon planting towns in Jiashi County. Symptoms include mosaic，blister mosaic，blister mosaic and malformation，leaf necrosis，leaf chlorosis，and fruit malformation. A total of 37 samples were collected，and the detection of WMV，CMV，and ZYMV was positive，but CGMMV，CABYV，and MABYV were not detected. 21.6%（8/37）of the samples were positive. WMV was the most prevalent virus detected in 18.9%（7/37）of the 37 samples collected，followed by CMV and ZYMV. Multiple infections were more frequent than single infections. F2/R2（P1 + HC-Pro），F4/R4（P3 + 6K1 + CI），F5/R5（CI + 6K2 + NIa-VPg），F6/R6（6K2 + NIa-VPg + NIa-Pro + NIb），and F8/R8（CP + 3′-UTR）fragments of different WMV isolates infecting Jiashi-melon have certain differences in the branches of the evolutionary tree，indicating that there may be recombination in the WMV genome.

• Figure/Table | References | Related Articles | Metrics

New Cultivars

• A New Kiwifruit Cultivar‘Wanhuang’
• JIA Bing, WANG Kecan, YE Zhenfeng, WANG Moucai, LIU Li, ZHU Liwu
• Acta Horticulturae Sinica. 2023, 50(8): 1803-1804. DOI:10.16420/j.issn.0513-353x.2021-0356
• Abstract ( 433 ) HTML ( 135 ) PDF (868KB) ( 135 ) 　　　

• ‘Wanhuang’is a new yellow-flesh kiwifruit cultivar bred from natural pollination progeny of‘Huangjinguo’. The fruit is oval，the top is protruding，the surface is short and less hairy，the peel is green brown，the flesh is golden yellow，the quality is fine and juicy，and the sweetness and acidity are moderate. The average fruit weight was 102.2 g，soluble solid content was 19.7%，sugar content was 15.3%，titratable acid content was 1.28%，vitamin C content was 720.2 mg · kg^-1. It matures in early October in Lu’an area，Anhui Province. The yield is 18 900 kg · hm^-2 in the full fruit stage.

• Figure/Table | References | Related Articles | Metrics

• A New Tomato Cultivar‘Yufan 421’with Late Blight Resistance
• PAN Guanghui, LUO Jia, YIN Xiangui, RU Xuejuan
• Acta Horticulturae Sinica. 2023, 50(8): 1805-1806. DOI:10.16420/j.issn.0513-353x.2021-0369
• Abstract ( 325 ) HTML ( 92 ) PDF (1145KB) ( 92 ) 　　　

• ‘Yufan 421’is a new F₁ hybrid of tomato developed by crossing W24 as female parent and S9 as male parent. It is determinate，early ripening，and middle vigorous. Fruit is rounded，red，no green shoulders，not firm and have traditional flavour. Average fruit weight is about 185 g，malformed and cracked fruit rate is about 13.2%，commercial fruit rate is about 83.4%，and shelf life is about 16 days. It is resistant to Late Blight，Fusarium and TMV，middle-resistant to bacterial wilt. Average yield is more than 65 000 kg · hm^-2. It is suitable for open cultivation in spring in Chongqing and Sichuan.

• Figure/Table | References | Related Articles | Metrics

• A New Cucumber Cultivar‘You NT 603’
• JIANG Suhua, WANG Linqing, WU Jingliang, NIU Suyan, Liu Jun, Cui Bo
• Acta Horticulturae Sinica. 2023, 50(8): 1807-1808. DOI:10.16420/j.issn.0513-353x.2021-0411
• Abstract ( 146 ) HTML ( 78 ) PDF (1157KB) ( 78 ) 　　　

• ‘You NT603’is a new cucumber variety of North China type maternal parent C306-3 and North China type paternal parent C406-5，which was bred by traditional crossing technique. The plant grows vigorously，the peel is dark green，the melon size is dense，there are few abnormal melons，the main vine，the fruit is 37 cm in length and the taste is crisp. It has strong disease resistance and high yield. The cultivation yield can reach 117 000 kg · hm^-2. It is suitable for cultivation in large arch sheds and overwintering greenhouses in Henan Province.

• Figure/Table | References | Related Articles | Metrics

• A New Watermelon Cultivar ‘Jinyuchun’
• HE Yanjun, WANG Yuhuan, LI Yulin, FAN Min
• Acta Horticulturae Sinica. 2023, 50(8): 1809-1810. DOI:10.16420/j.issn.0513-353x.2021-0534
• Abstract ( 162 ) HTML ( 90 ) PDF (898KB) ( 90 ) 　　　

• ‘Jinyuchun’is a new watermelon cultivar crossed by inbred lines S1288 and S1252. The fruit development period is about 30.8 d. The fruit shape is spherical and the average shape index is 1.2. The peel is green with clear dark green stripes and wax powder. The rind thickness is about 0.8 cm. The flesh color is yellow and the center soluble solids content is about 12.7%. The single fruit weight is about 2.6 kg. The yield is about 30 000 kg · hm^-2 in protected fields. It is middle resistant to Fusarium wilt and anthracnose. It’s suitable for planting in the spring and summer in Zhejiang Province.

• Figure/Table | References | Related Articles | Metrics

• A New Cultivar of Ornamental Lotus‘Hongyishuai’
• REN Liping, SU Xiaohui, WAN Wenyang, YU Linjie, LIU Bin, CAO Xiaohan
• Acta Horticulturae Sinica. 2023, 50(8): 1811-1812. DOI:10.16420/j.issn.0513-353x.2021-0706
• Abstract ( 208 ) HTML ( 118 ) PDF (1020KB) ( 118 ) 　　　

• Ornamental lotus‘Hongyishuai’is a new cultivar obtained by artificial hybridization breeding of lotus‘Zilian’and‘Xintongshuai’. It is a medium and large plant with multiple petals and deep red color. The plant height is 64-72 cm and the leaf height is 60-68 cm under the cylinder with the diameter of 50 cm. Flower density is 6-7 per cylinder，flower stalk is 66-70 cm high，flower diameter could reach 19-21 cm，number of petals is 51-55，the flower bud is long peach shape，and the flower state is disk-shaped. Mature lotus is cup-shaped，and mature lotus seed is oval. Suitable for neutral soil cultivation in the Huanghuai and Yangtze River basins.

• Figure/Table | References | Related Articles | Metrics