In this study，the role of MhCLE8（CLAVATA3/EMBRYO SURRSURROUNDING REGION 8）peptide hormone gene in regulating anthocyanin accumulation was investigated using the meterials Arabidopsis and apple calli. The results showed that the accumulation of anthocyanin in Arabidopsis seedlings and apple calli was significantly inhibited when treated with MhCLE8 peptide （referred to as MhCLE8p）which was synthesised in vitro. Phylogenetic analysis and multiple protein sequences alignment showed that MhCLE8 and its homologues in other plant species contain a highly conserved CLE-motif，and MhCLE8 showed high homology with Prunus armeniaca（CAB4276204.1）and Malus baccata（TQE01035.1）. The MhCLE8 gene was cloned to binary vector pRI，and transferred to Arabidopsis and apple calli to obtain the stable overexpression materials by Agrobacterium-mediated transgenic technology. The transgenic Arabidopsis seedlings and apple calli showed decresed accumulation of anthocyanin. The qRT-PCR analysis showed that the expression of anthocyanin biosynthesis structural genes in MhCLE8 overexpressed plant materials was inhibited to varying degrees. In summary，all the results suggested that the peptide encoding gene MhCLE8 was a negative regulator of anthocyanin accumulation.

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.

In the current study，the flowers of three grape varieties‘Beichun'（hermaphrodite），‘1613C'（male） and‘520A'（female）were chosen. Hormone determination and transcriptome sequencing were performed at the early bud stage，large bud stage and blooming stage. The accumulation of various plant hormones in flowers of different genders was different，and so was that in flowers of the same gender at different developmental stages. The contents of IAA，ABA and MeJA were the highest in the large bud stage of female flowers. A total of 31 965 expressed genes were obtained，and 1 535 genes were directly related to flower development and were mainly involved in phenylpropane synthesis and plant hormone signal transduction pathways. Some genes are continuously up-regulated or down-regulated at different developmental stages. The genes that are continuously up-regulated are mainly involved in Phenylpropane synthesis，plant hormone signal transduction and other pathways. The genes that are continuously down-regulated are mainly involved in starch and sugar metabolism，and amino acid synthesis. MADS-box genes，such as AP1，SEP1，AG2 and SOC1 were significantly differently expressed in different floral organs at developmental stages. During flower sex differentiation，the differential expression of the MADS-box gene，the flower-induced integron gene，and the detoxification and stress-related genes play important roles.

In this study，a total of 296 pear germplasms from National Horticulture Germplasm Resources Center Pear Branch Center（Zhengzhou）were collected for fruit spots observation，data collection and photography. During fruit harvesting period，the indicated pear germplasms were sampled and different fruit spot traits，including fruit spots size，fruit spots density，fruit spots height，and the fruit spots area in unit area were comprehensively analyzed. Additionally，sensory evaluation of fruit appearance quality associated with fruit spots in different pear germplasms was performed，and the apperance quality of different pear germplasms was evaluated by grey relation analysis（GRA）and cluster analysis（CA）to establish a comprehensive evaluation model for pear fruit spot traits. The results showed that the relative correlation degree of fruit spots of 296 pear resources ranged from 0.3158 to 0.6526，and the 296 resources were classified into five grades：excellent，good，medium，poor，and extremely poor. Pear varieties including‘Autumn Red’‘Silk Red’‘Red Sensatian’‘Zhongli Meicui’‘Barlett’and‘Dabali’were screened out with excellent fruit spot traits，which have good appearance quality and were consistent with the actual production fruit exterior. On the contrary，pear varieties including‘Puguali’‘Xihuamake’‘Chili’and‘Enli’were screened out with extremely poor fruit spot traits，which have poor appearance quality. Furthermore，the fruit spot traits of 296 pear germplasm resources were divided into five grades by cluster analysis，including excellent，good，medium，poor and extremely poor，which accounted for 7.8%，8.8%，37.1%，34.1% and 12.1% of the tested materials，respectively. Above all，the germplasm resources with excellent fruit spot traits will lay the foundation for the improvement of pear appearance quality，and the germplasm resources with poor fruit traits will be helpful for the investigation of the formation and regulation mechanism underlying pear fruit spots.

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.

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.

Ubiquitin-conjugating enzyme E2 is a key enzyme for substrate ubiquitination reaction，which plays an important role in the mechanism of self-incompatible by S-RNase degradation via ubiquitin-proteasome system. An E2 gene was cloned based on EST sequence（EY715921）of Citrus sinensis using the flower buds from‘Wuzi Shatangju’and‘Shatangju’，named as CrUBC2. The full-length cDNA sequence of the CrUBC2 was 965 bp，encoding 152 amino acids. There was one base difference （C/T）in the coding sequence of CrUBC2 between‘Wuzi Shatangju’and‘Shatangju’，which resulted in the conversion of threonine to isoleucine. Multiple sequence alignment showed that only one amino acid difference（Thr/Ile）was found between CrUBC2 and orthologs. Therefore，CrUBC2 protein was highly conservative during the evolution process. qRT-PCR showed that the highest expression level of the CrUBC2 was detected in anthers，and the expression level of the CrUBC2 after cross-pollination was 2.22-5.36 fold higher than that of self-pollination，indicating obvious expression specificity in different pollination. Pollen germination experiment in vitro showed that CrUBC2 protein of‘Wuzi Shatangju’inhibited significantly the growth of pollen tubes of self-pollination，but it had no effect on the growth of cross-pollination pollen tubes，which may be related to its involvement in S-RNase ubiquitination and resulting in cross-compatibility.

Fruit ripening has always been the focus of horticultural plant research. Plant hormone abscisic acid（ABA）plays an irreplaceable role in fruit ripening. This review summarizes the recent advances in the regulation of ABA on fruit ripening，providing reference for further improvement of the regulation network of fruit ripening.

The new cultivar‘Zixia'is derived from the cross Dendrobium Ekapol‘Big Panda'and Dendrobium‘Yuki'. The flower color is purple and bright and the average single branch has 5.3 flowers with flower diameter of 6.8 cm and the branch length is 35.0 cm. The beginning flower of this cultivar is in October and full bloom is November and December when cultured in greenhouse of guangzhou，and can be widely planted in South China.

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.

Twenty-one quantitative characters（weight of single fruit，stone weight，a thouthand kernel weight，total sugar content，titratable acid content，etc.）of Ziziphus jujuba Mill. var. spinosa（Bunge）Hu ex H. F. Chow fruits'genetic variation rule and genetic diversity were studied in 393 wild jujube germplasm from follow provinces of Hebei，Liaoning，Shandong，Shaanxi．The results showed that the wild jujube germplasm was rich in genetic diversity. The obvious variety was observed with18 quantitative characters. The Shannon's index of the 18 quantitative characters exceeded 1.0. The degree of genetic diversity between various regions was distinctly different，and the upper-to-lower order of the various regions based on Shannon's index was Xingtai（H' = 1.198），Handan（H' = 1.147），Chaoyang（H' = 1.120），Baoding（H' = 1.069），Yulin（H' = 0.953），and Tai'an（H' = 0.733）. Cluster analysis divided the wild jujube germplasm into three groups，North China，Shaanxi，Liaoning. The wild jujube germplasm in North China（mainly represented by Xingtai）was the richest in quantitative diversity，which provides a wealth of material to choose for the breeding. The principal component analysis on quantitative characters result showed that the accumulative contribution rate of the first four principal components accounted for 71.85% in the total variation accounted，and the first principal component mainly reflected the fruit mass and a thouthand kernel weight，while the second principal component reflected the titratable acid content. The third and fourth principal component reflected stone vertical diameter and vitamin C content，respectively.

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.

Pollen-pistil interaction plays an important role in evolutionary process of species by influencing pollen affinity and serving as reproductive barriers，which determines the reproductive mode of higher plants. Therefore，on the one hand，cloning of male or female recognition factors is the basis of in-depth understanding of plant reproduction mode，which is of great significance for the analysis of the evolutionary mechanism of species. On the other hand，for crop breeding practices that rely extensively on selfing or hybridization，in-depth analysis of the function and mechanism of male or female recognition factors is also of great breeding value. In this review，the current research progress of pollen-pistil interaction factors were summarized systematically，especially in Arabidopsis thaliana，tomato，torenia and other model crops for pollen-pistil recognition research. The structure of pollen and pollen tube，and the S-locus，which determines self-incompatibility，are firstly introduced. Then，according to the sequence of pollen tube extension on female organs，stigma，style and ovule were introduced，and the correlation and uncorrelation between self-incompatibility and cross-incompatibility were introduced in detail. Finally，the research focus of pollen-pistil interaction was prospected.

In China，there are four kinds of important deciduous fruit trees with a cultivation area of over 666 700 hm²：apple，pear，peach and grape. According to the quality and maturity，several generations of domestic genetic breeders，after decades of collaborative innovation and joint research，created a high-quality and efficient breeding technology system on the basis of excellent germplasm evaluation and creation，and bred a series of high-quality new cultivars of apples and pears with high quality，storability，different maturity and diverse characteristics，and bred high-quality new cultivars of peaches and grapes in early，middle and late maturity. A high-quality and efficient supporting cultivation technology system for new cultivars has been developed，which has promoted the large-scale popularization and application of independent research and development of new cultivars and the high-quality and efficient development of the industry，and provided important support for ensuring the annual demand for high-quality fruits.

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.

The patterns of anthocyanin and ABA accumulation and ethylene production as well as the changes in expression of the key genes associated with their synthesis or regulation during berry development were studied using Kyoho grapes（Vitis vinifera × V. labrusca‘Kyoho’）. Analysis of gene expression，promoter response and relative mRNA abundance showed that exogenous ABA treatment upregulated the expression level of VlMybA1 and VlMybA2，in which VlMybA1 was significantly expressed and promoted berry skin pigmentation；In contrast，exogenous ACC treatment increased the VlMybA2 expression and anthocyanin accumulation. The interaction between ABA and ethylene was found，100 μmol · L^-1 ABA largely induced the production of endogenous ethylene，and 500 μmol · L^-1 ACC significantly increased ABA content. Additionally，exogenous ABA treatment increased the relative mRNA abundance of VlMybA2 via ethylene. Collectively，ABA promoted berry skin pigmentation by upregulating the VlMybA1 expression directly and the VlMybA2 expression indirectly via ethylene.

The production of flowery panicles of loquat requires a lot of artificial flower and fruit thinning and sacking，which greatly increases the production cost. Therefore，the study of loquat inflorescence characteristics and the exploration of structure of inflorescence which is convenient for production are the important basis for high yield，high quality and low consumption of loquat industry. This paper reviewed the development and evolution of loquat inflorescence，the regulation of genes related to flowering and inflorescence formation，and the effects of the internal and external factors on loquat inflorescence formation. And further put forward the existing problems and research prospects，in order to provide a reference for the subsequent research on the formation mechanism of loquat inflorescence and lay a foundation for the study of good loquat inflorescence cultivars.

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.

Strawberry aroma is one of the important factors contributing to their quality. Strawberry aroma is composed of complex combinations of volatile，such as esters，aldehydes，ketones，alcohols，terpenoids，furanone and sulfur-containing compounds. Among them，furanone，methyl butyrate，ethyl caproate，γ-decalactone，and linalool and nerolidol represent the most important aroma compounds of strawberry. This review aims to describe the recent advances in understanding aroma biosynthesis in strawberry fruit，including the aroma composition，biosynthetic pathways，key regulatory genes，as well as the major factors affecting the aroma quality. Finally，an outlook on the future research trends of strawberry aroma is provided.

‘Dongshi Zaoyou’，a new pummelo cultivar selected from pummelo seedlings，is mainly cultivated in the tropical areas of Yunnan Province. It has good characteristics such as early-maturing，high-yielding，seedless and etc. However，the genetic origin of‘Dongshi Zaoyou’pummelo has not yet been clarified，which was unfavorable to its protection and utilization. In this study，the cross-compatibility test and molecular markers including self-incompatibility S-genotype，SNP and InDels were used to explore the genetic background differences between‘Dongshi Zaoyou’pummelo and its two similar cultivars ‘Shatianyou’，‘Shuijingyou’. The pollination experiments revealed the cross-incompatibility between‘Dongshi Zaoyou’pummelo and‘Shuijingyou’pummelo while the cross-compatibility between‘Dongshi Zaoyou’pummelo and‘Shatianyou’pummelo. Accordingly，S-genotype of‘Dongshi Zaoyou’pummelo was judged to be S₅S₆，the same as that of‘Shuijingyou’pummelo（S₅S₆），while different from that of ‘Shatianyou’pummelo（S₁S₂）. Based on the genome resequencing data，the genome-wide SNP density distribution of three pummelo cultivars were then plotted and compared. The results showed that‘Dongshi Zaoyou’pummelo and‘Shuijingyou’pummelo had highly similar SNP density and clustered into a group，but they both were significantly different from‘Shatianyou’pummelo. In addition，two InDel polymorphic markers could clearly distinguish‘Dongshi Zaoyou’pummelo from‘Shatianyou’pummelo. Collectively，it could be concluded that‘Dongshi Zaoyou’pummelo showed a closer relationship to‘Shuijingyou’pummelo than‘Shatianyou’pummelo.