The collected leaves and soil samples from 243 sampling units in representative orchards of Guangdong Province and determined their micronutrient concentrations. There was a relatively high significant difference in leaves Cu and Mo as well as soil available Mn,Cu,Zn,and B contents,while similar contents were found in leaves B and soil available Mo. Most of the leaves B and soil available Mo were in the optimum ranges（> 60%）,while most of the leaves Mo and soil available B were in the deficiency level（> 50%）in orange,grapefruit,and mandarin orchards. In orange orchards,all soil available B and Mn,as well as most of leaves Zn（77.8%）,soil available Cu（50.0%）,and Zn（55.6%）were in the deficiency level. The soil available Zn and leaves Cu in grapefruit orchards,and soil available Cu and Fe in orange and mandarin orchards were in the excess level. The distribution proportion of micronutrients in leaves and soil available Fe,Mn,and Mo of different tree ages were similar. The excess percentage of soil available Cu in short-age（3-8 years old）and old trees（> 8 years old）（> 60%）was higher than that of young trees（< 3 years old）（48%）. There were significant positive correlations between leaves and soil available Fe,Mn,Cu,and B in mandarin orchards,as well as between leaves and soil available Fe and Cu in grapefruit orchards. Fitting indicators of leaves and soil available Fe,Mn,and Cu in grapefruit orchards were higher than that of orange and mandarin orchards. There was a significant positive correlation between leaves and soil available Mn,Cu,and B in both old and short-age trees,and between leaves and soil available Zn in short-age trees. The fitting indicators between leaves and soil available Fe of different tree ages were as follows: young trees > short-age trees > old trees. Canonical correlation analysis results show that leaves Cu in mandarin and grapefruit orchards,leaves B and Fe in old trees,and leaves Mo and Mn in short-age trees could be used to diagnose the abundance or deficiency of micronutrient in different species and ages of citrus orchards. Soil available Zn and B in mandarin orchards and short-age trees,soil available Cu in grapefruit orchards,and soil available B and Fe in old trees were the key factors affecting the tree micronutrient among different species and ages of citrus orchards,which should be paid more attention in the management of citrus orchard fertilization.

To clarify the relationship between the ease of peeling of mandarins and cell wall polysaccharides,which are thought to support the plant cell integration,adherence and mechanical strength,the ease of peeling,peel morphology,cell wall polysaccharide contents,the activities of the enzymes related to cell wall polysaccharide degradation and the expression level of some related genes were analyzed in four mandarin varieties,Citrus reticulata Blanco‘Mukaiyama’,C. clementina hort. ex. Tanaka,C. reticulata Blanco‘Fremont’and C. reticulata Blanco‘Yaoxianggan’. During the fruit ripening,peel adherence and firmness,which reflect the ease of peeling,remarkably decreased,suggesting that the peeling is easier as the fruit mature. In different varieties,the ease of peeling also showed great diversity. Fremont and Yaoxianggan had higher peel adherence than Mukaiyama and Clementine,and Yaoxianggan had the highest peel firmness in the four varieties,whereas Mukaiyama and Clementine had the similarly lowest peel firmness,indicating that Fremont and Yaoxianggan were hard peeling and Mukaiyama and Clementine were easy peeling. The correlation analysis indicated the significant positive correlation between the peel adherence and firmness,and that the ease of peeling is relevant to the low level of cell wall polysaccharides and high activities of their degradation-related enzymes. The contents of cell wall polysaccharides in all varieties dramatically dropped during the fruit maturation,and coincidently,the activities of some enzymes related to cell wall polysaccharide degradation and the expression level of the encoded genes also ascended. At the same time the expression of some genes encoding xylanase inhibitors and pectin methylesterase inhibitors was decreased. In these four varieties,the peels in the easy-peeling Mukaiyama and Clementine had lower content of total cell wall biomass as well as some polysaccharide fractions including hemicellulose,cellulose and protopectin,which were relevant to the higher activities of xylanase,cellulose and pectin degradation-related enzymes. Nevertheless,the pivot gene controlling the distinct ease of peeling in different varieties remains obscure.

Samples were first collected from nine regions in China. A total of 17 Xanthomonas axonopodis pv. citri（Xac）strains were isolated and identified by single colony morphology,specific PCR primers and 16S rDNA sequencing step by step. Then,the standard Xac strain ACCC 03526 was selected as the host bacteria. One strain of Xac virulent phage named Xac-P9 was isolated from the sewage of Nanjing using a double-layered plating procedure. The morphological size of Xac-P9 was observed by transmission electron microscope（TEM）. The head of Xac-P9 had a diameter of about 58 nm,suggesting that it belongs to the Podoviridae,Caudovirales. The biological characteristics of Xac-P9,such as lysis spectrum,optimal multiplicity of infection（MOI）,one-step growth curve,thermal stability,pH stability,UV sensitivity and rate of bactericidal action,were determined. The lysis rate of Xac-P9 against 17 Xac strains of different origins was 100%. The highest phage titer was 6.6 × 10⁹ PFU · mL^-1 when the MOI was 0.001. The latency,burst time and burst size were 20 min,60 min and 132,respectively. Xac-P9 was tolerant at 40-60 ℃ and active in the pH range of 3 to 13. The tested phage was not sensitive to UV light;and Xac-P9 killed 90% of the host bacteria ACCC 03526 at 30 min and all host bacteria at 150 min.

Auxin plays a crucial role in regulating the growth and development of plants. The acyl acid amido synthetase Gretchen Hagen 3（GH3）may modulate auxin levels via conjugting both indole-3-acetic acid（IAA）and salicylic acid（SA）in response to environment changes. In the current investigation,genome-wide identification and comprehensive analysis of the GH3 gene family in sweet cherry（Prunus avium）were conducted using the genomic sequence. Totally,eight members of PavGH3 genes were identified from the whole genome of sweet cherry,which are not evenly distributed on the chromosomes,with the coding sequence of 1 683-1 851 bp,most of which were forecasted in chloroplast. The analysis of gene structure and domain revealed that PavGH3 demonstrated high similarity among the members,and the number of exons was three or four. A total of 16 conserved domains were obtained,and the number of the conserved domains varied among the members. These gene members were clustered into two major groups（I and II）,based on phylogenetic analysis. Sequence analysis of promoters showed many cis-regulatory elements which presumably responsed to phytohormones such as abscisic acid,methyl jasmonate etc. Synteny block indicated that PavGH3.5 and PavGH3.6 showed collinearity with GH3 in Arabidopsis thaliana,suggesting that they were evolutionarily conserved. Multiple sequence alignment demonstrated that these members are highly similar and conserved. As detected by qRT-PCR in 17 tissues. PavGH3.2,PavGH3.3 and PavGH3.6 were highy expressed in these tissues. PavGH3.4 and PavGH3.5 were up-regulated in the dropped-fruit of the second physiological abscission in comparison with that of the first one. Compared with retention fruits,surprisingly,PavGH3.5 and PavGH3.7 were significantly down-regulated in the first physiological fruit drops,PavGH3.4 and PavGH3.6 were up-regulated. IAA,GA₃,ABA and MeJA were used to foliar application,and PavGH3.2,PavGH3.3,PavGH3.6 and PavGH3.7 were differentially expressed in response to the type and application stage of the phytohormones,however,no responses were observed in the others. Therefore,it is speculated that the PavGH3 gene family is considerably involved in the regulation of the growth and development of sweet cherry,and probably in the fruit abscission.

In this study,569 mulberry germplasm resources of nine mulberry species（Morus atropurpurea Roxb.,M. alba L.,M. multicaulis Perr.,M. rotundiloba Koidz.,M. australis Poir,M. mallotifolia Koidz.,M. serrata Rox.,M. celtidifolia Kunth.,M.cathayana Hemsl.）were rated and evaluated by selecting eight important agronomic traits,which were plant height,shoot-sprouting number,internodal distance,bud number of per meter branch,fruits-set number per meter branch,percentage of fruits-set,fruit number per meter branch and fruit number per bud. Based on the rating data of agronomic traits,569 mulberry germplasm resources were identified and evaluated by variation analysis,correlation analysis,principal component analysis,cluster analysis and discriminant analysis. The results of variation analysis showed that these mulberry germplasm resources had relatively rich genetic diversity,and the variation coefficients of the eight agronomic traits ranged from 33.41% to 49.24%,among which the largest coefficient of variation was the number of fruits per meter branch and the smallest was plant height. The genetic diversity index of these 8 agronomic traits ranged from 1.26 to 1.79,which was the highest internode length. The correlation analysis showed that shoot-sprouting number was significantly positively correlated with fruits-set number per meter branch,percentage of fruits-set,fruit number per meter branch and the number of fruit number per bud. Principal component analysis of these eight agronomic traits showed that the additive contributing rate of first three principal components was 80.367%. Based on principal component results,569 mulberry germplasm resources were divided into 5 groups by cluster analysis. 113 germplasm with good agronomic traits were selected,accounting for 19.86% of all primes. Therefore the fruit mulberry germplasm resources of the group 5,such as TAI1,JP2,BR60,Ding50,YY201 and QM1,can be used as materials for breeding superior fruit mulberry cultivars.

Two indole-3-acetic acid methyltransferase（IAMT）genes,SlIAMT1 and SlIAMT2,were cloned from tomato cultivar‘Ailsa Craig’. The full-length of SlIAMT1 and SlIAMT2 genes were 2 510 and 4 620 bp,respectively,and both of them encode 390 amino acids. The sequence alignment suggested that both SlIAMT1 and SlIAMT2 contained all of the substrate binding sites and catalytic sites for IAMT,and showed more than 70% sequence identity with AtIAMT1 from Arabidopsis. In silico analysis suggested that the promoter sequences of SlIAMT1 and SlIAMT2 contained several typical cis-acting elements,including auxin-,abscisic acid-,salicylic acid- and light-responsive elements by using PlantCARE databases. Real-time PCR assays showed that SlIAMT1 was highly expressed in the germinating seeds,roots of 5-d-old seedlings,young leaves and green fruits,while SlIAMT2 was extensively expressed in the flower buds. In tomato seedlings,the expression of SlIAMT1 was remarkably induced by high light intensity（150 μmol · m^-2 · s^-1）,especially in the hypocotyls. However,the inducible level of SlIAMT2 was much lower. The induction of SlIAMT1 and SlIAMT2 was low by low temperature（15 ℃）treatment. IAA also exerted inducible effects on SlIAMT1 and SlIAMT2 expression. ABA induced the expression of SlIAMT1 in root and hypocotyl,but repressed its expression in cotyledons,while for SlIAMT2,its expression was repressed by ABA in root. SA repressed the expression of SlIAMT1 in roots and cotyledons,but slightly induced SlIAMT2 expression in cotyledons. The function of SlIAMT1 gene was further investigated by Agrobacterium-mediated genetic transformation into Arabidopsis. The iamt1 mutant showed longer hypocotyl and primary roots than wild type,and these phenotypes of mutant were functionally complemented by overexpression of SlIAMT1. Overexpression of SlIAMT1 could also reduce the sensitivity to IAA in lateral roots. These results indicated that SlIAMT genes respond to light and hormone signals,and regulate the IAA homeostasis via methylation and thereby regulate the hypocotyl and root development.

Fructan is the main storage material of garlic,and its metabolism is closely related to yield formation and stress adaptability. In order to understand the sequence characteristics and expression patterns of fructan：fructan 6G-Fructosyltransferase gene（As6G-FFT）in different tissues and stress conditions of garlic,the As6G-FFT（fructan：fructan 6G-Fructosyltransferase）gene was cloned from ‘Ledu Purple Skin Garlic’. The CDS full length of As6G-FFT gene was 1 839 bp,encoding 612 amino acids with molecular mass of 68.64 and theoretical isoelectric point of 5.43. It was a hydrophilic protein and contained three important conserved domains of NDPSG,RDP and EC of plant glycosylhydrolase 32 family. In terms of evolutionary relationship,garlic As6G-FFT gene was close to onion. The result of subcellular localization showed that As6G-FFT protein was located in endoplasmic reticulum. qRT-PCR analysis showed that As6G-FFT was expression in all tissues examined,which expression level was leaf > root > mother petal > pseudostem. In addition,the expression characteristics of As6G-FFT gene in different tissues were also different after low temperature（4 ℃）or drought stress treatment（45%-55% relative water content of matrix）. Compared with other tissues,drought stress could induce the expression of As6G-FFT gene in roots earlier,whereas the expression of As6G-FFT in mother petal was more sensitive under low temperature stress,which indicated that the response mechanism of As6G-FFT in garlic tissues to stress signals was different.

The F₁ generation was obtained by crossing the parental material‘zx-15’and the maternal material‘zx-101’,and then the F₂ population was obtained by F₁ self-crossing. Genetic law of 11 fruit and seed traits of the F₂ group were analyzed,and the path analysis of single fruit weight was also conducted. Results showed that the presence or absence of wax powder,seeds with or without angles and seed coat with or without hairs were controlled by a single dominant gene;single fruit weight,fruit length,fruit width,fruit thickness,fruit hardness,fruit color,cavity size and soluble solids content were all quantitative traits. The optimal genetic model for fruit thickness was MX2-ADI-ADI,for fruit hardness,soluble solids content and cavity size was MX2-ADI-AD,and for fruit color was 2MG-AD;soluble solids content,cavity size and fruit color had higher heritability of main genes,while single fruit weight and fruit width were controlled by micro-effective polygenes and were greatly affected by the environment. A stepwise regression was used to establish the regression model equation for the factors influencing the single fruit weight of wax gourd,and the path analysis showed that fruit length and width were the main factors affecting the yield of wax gourd,in which the direct and mutual indirect influences played equal roles.

The morphological characteristics of pollen of 30 species of plants of seven genera in Gentianaceae in Shergyla mountainous area of Tibet were observed and studied by scanning electron microscope. The pollen of these 30 species of Gentianaceae were all single-grain pollen with three grooves. There are certain differences among various species. Pollen in the equatorial view is divided into super rectangular,nearly rectangular,elliptical,and fusiform;in polar view,there are three types of three-lobed round,triangular-shaped,and near-triangular,mainly three-lobed round;pollen volume index between species,the length difference between the polar axis and the equatorial axis is more obvious;there are five types of pollen outer wall decorations：stripe-reticulate,reticulated,hole-shaped,brain-shaped reticulate and reticulated carving. Finally,the significance of the observed 30 species of Gentianaceae pollen in the morphological characteristics of Gentianaceae plant evolution,genetic relationship and systematic classification were discussed.

In this study,the drought and waterlogging tolerance and their stability across different trials were evaluated by principle component analysis,membership function,cluster analysis,and additive main effects and multiplicative interaction（AMMI）model for 54 tea chrysanthemum accessions at seedling stage. The results showed that the average coefficient of variation for drought and waterlogging tolerance were 25.21% and 33.71%,respectively,across two trials in June and July. The principle component analysis extracted each four main components from ten drought and waterlogging-related traits that could explain 81.36% and 80.52% of phenotypic variation,respectively. The membership function value-based clustering analysis grouped the investigated tea chrysanthemums into four drought resistance types（resistant,moderate resistant,not resistant,and susceptible）and four waterlogging tolerant types（tolerant,moderate tolerant,not tolerant,and susceptible）,and significant differences were observed among different tolerance types. A total of seven drought and five waterlogging tolerant accessions were excavated,and the stability of drought tolerance for the seven accessions were sorted as‘Fubaiju’> ‘Chuju’> GH7-2 >‘Huang Xiaoxiangju’> HC6-12 >‘Jinju 3’> CH,while the stability of waterlogging tolerance of the five accessions were sorted as GH9-33 > GH7-2 > GH7-32 >‘Hangbaiju’> CH. In addition,CH,GC1-16,‘Hongxinju’,and‘Chuju’showed relatively strong tolerance to both drought and waterlogging stresses based on the AMMI analysis.

The protein phosphatase 2C（PP2C）family genes of Dendrobium catenatum Lindl. were identified and analyzed by bioinformatics method. The expression patterns of PP2C genes in different tissues and under various abiotic stresses and hormones were analyzed by quantitative real-time PCR （qRT-PCR）. A total of 67 family members were identified,which encode 80 to 1 075 amino acids,and the molecular weight were between 8.86 to 119.59 kD,and the isoelectric points ranged from 4.13 to 9.36. The PP2C proteins were divided into 13 subgroups by phylogenetic tree analysis,and the conserved motifs of each subgroup were similar. The number of exons in PP2C gene ranged from 1 to 15. Spatial expression pattern analysis showed that four PP2Cs had the highest expression in gynostemium of D. catenatum,and five genes had the highest expression in capsule and one gene had the highest expression in root,indicating that the expression of PP2C was tissue-specific. The expression levels of DcPP2C5,DcPP2C20 and DcPP2C56 were significantly up-regulated by drought stress（20% PEG6000）. DcPP2C24 was significantly up-regulated by high temperature（42 ℃）. And DcPP2C5 was up-regulated by low temperature（4 ℃）. DcPPC20 was induced by salt stress（200 mmol · L^-1 NaCl）, and the expression of these genes were all induced by 100 μmol · L^-1 ABA and 20 μmol · L^-1 SA to some degrees,suggesting that they played roles in response to the stresses in D. catenatum.

Three-year-old‘Fujiminori’grapes grafted on‘SO4’were grown in sunlight greenhouse and three renewal pruning treatments（10,20 and 30 days after harvest）were set to compare the effects on the growth and fruit quality of‘Fujiminori’grape. The results indicated that the renewal pruning treatments could promote the germination of winter buds and the growth of new shoots at various extent,but the late renewal pruning treatment led to the short growth time of new shoots and the incomplete development of branches. Renewal pruning could effectively advance the phenological period of grape,of which the ripening of grape berries could be advanced with 20 and 13 days by renewal pruning at 10 and 20 days after harvest,respectively. Three renewal pruning treatments significantly increased the grape yield per plant,reaching 3 610.3,3 372.8 and 2 874.5 g,respectively,which were significantly higher than that of the control group（975.2 g）. Renewal pruning treatments effectively increased the total soluble solids and anthocyanin content of grape berries,decreased their titratable acid content,whereby promoting berry ripening and quality improvement. Renewal pruning treatments at 10 and 20 days after harvest showed more significant effect mentioned above than late renewal pruning（30 days after harvest）.

To study the potential function of longan TCP gene family,bioinformatics methods were used to perform the genome-wide identification of family in Dimocarpus longan TCP genes（DlTCP）. The expression patterns of DlTCP in longan somatic embryo development and their responses to ABA and MeJA were detected by the real-time quantitative PCR（qRT-PCR）. In this study,20 longan TCP gene family members were identified in the longan genome database. These DlTCP proteins contained 169- 540 amino acid residues,with molecular weights ranging from 39.6 kD to 57.2 kD,and theoretical isoelectric points ranging from 5.90-9.45. The prediction of subcellular localization showed that 18 members were located in the nucleus. DlTCP were distributed on 11 of the 15 chromosomes of longan. Synteny analysis revealed that 12 of DlTCP were involved in fragment replication events. Promoter cis-acting elements analysis showed that DlTCP family members contained hormone response cis-acting elements and regulate growth and development cis-acting elements. The longan TCP family members can be divided into two categories in phylogenetic evolution,and they all had typical TCP domains. QRT-PCR results showed that DlTCP2/4a/4b/13/17/18/19/23 were highly expressed in the embryogenic callus（EC）stage,DlTCP5b/8 were highly expressed in the incomplete compact pro-embrogenic cultures（IcpEC）stage,and only DlTCP20a was highly expressed in the globular embryos（GE）stage,indicating that the higly expression of DlTCP may contribute to the morphogenesis of early somatic embryos in longan. In addition,the family members also exhibited different expression patterns after exogenous hormones treatments. After exogenous ABA induction,the expression of four DlTCP members was significantly down regulated,and four were up-regulated;After MeJA induction,the expression of three members was significantly down-regulated and four up-regulated,indicating that DlTCP members can respond to ABA and MeJA.

As a potentially harmful virus,plantago asiatica mosaic virus（PlAMV）has been reported to infect lilies and other crops in China,so it is urgent to establish a monitoring and control system to prevent its spread. In this study,specific primer pair CP-2F/R were designed based on the conserved region of coat protein（CP）gene of PlAMV. By optimizing concentration of primers and annealing temperature,an efficient real-time fluorescent quantitative polymerase chain reaction（RT-qPCR）was established with optimal primer concentration of 10 μmol · L^-1 and optimal annealing temperature of 59.4℃. The sensitivity of this assay was 100 times higher than that of conventional RT-PCR,and the limit of detection by RT-qPCR was 13 copies · μL^-1. The established RT-qPCR was used to detect PlAMV in 75 lily samples,with conventional RT-PCR used as a reference method,and the results showed that more positive samples were detected by RT-qPCR （29,38.67%）than by RT-PCR（21,28.00%）.

Flavonoids are the most abundant secondary metabolites in grape. These compounds play vital roles in grape growth and development,resistance to ultraviolet radiation and diseases/insects,berry coloration and flavor quality,as well as nutritional values. Grape berries possess various types of flavonoids,which show variety-,tissue-,and development-specific accumulation characteristics. Flavonoid metabolism in grape is mainly regulated by UDP-glucose：flavonoid 3-O-glycosyltransferase（UFGT）and MYBA1 genes,and also affected by a variety of biotic and abiotic factors. The review summarizes recent data related to the flavonoid metabolism from the aspects of biological functions,composition and accumulation characteristics,biosynthesis and regulation mechanisms,and influencing factors. Finally,the future research directions of grape flavonoid metabolism are also put forward from the aspects of perfecting flavonoid content database,uncovering important gene functions,analyzing metabolic regulation networks,and exploring the interaction mechanisms of multiple factors.

"Yujinmi 2" is a yellow-fleshed and mid-maturing peach cultivar derived from natural cross of "Qiumihong" which is a latematuring peach cultivar. The fruit of "Yujinmi 2" with less hair is ovate in shape. The fruit is yellow-fleshed and free-stone. The average and maximum single fruit weight are 220 g and 307 g,respectively. The soluble solids content of fruit is from 13.3% to 14.8%. The fruits matured on July 25 in Zhengzhou,Henan Province. The fruit development period is about 115 d. The yield of 5-years trees is up to 37 500 kg · hm^-2.

The Phalaenopsis cultivar"Minixiang"is bred by artificial self-crossing with parent"Sogo Vivien". The plant width is 17.1 cm,the length and width of the leaf are 9.6 cm and 4.2 cm. The number of pedicels per plant is 1.5,and the length of flower branches is 15.4 cm. There are 10.6 flowers in the main inflorescence and 14.8 flowers on the whole which have good arrangement. The diameter of flower is 3.4 cm with round and good design,and its flower color is purple. It is suitale for the protected cultivation.