Abstract:To reveal the the complex relationships between the characteristics of interspecific associations and communities succession in the succession process of pine oak forests community on the south-facing slopes in Qinling Mountains. Based on 2?2 contingency tables, we used the Variance Ratio, χ2 test and Jaccard index and Spearman’s rank correlation coefficient to study the characteristics of interspecific association and correlation among main plant populations of different successional stages in the successive serials from Pinus tabulaeformis forest to P. tabulaeformis-Q. aliena var. acuteserrata mixed forest then to the subsequent Quercus aliena var. acuteserrata forest on the south-facing slopes in Qinling Mountains. The results showed that: (1) The overall interspecific associations of dominant species in Pinus tabulaeformis forest, Quercus aliena var. acuteserrata forest and Pinus tabulaeformis-Quercus aliena var. acuteserrata mixed forest are significant positive connection, each communities has a relative stability. (2) The positive and negative interspecific associations and correlation percent of main species in Pinus tabulaeformis forest and Pinus tabulaeformis-Quercus aliena var. Acuteserrata mixed forest is smaller, and their community stability are inferior to Quercus aliena var. Acuteserrata forest.(3)Interspecific competition Among pioneer species, pioneer species and prior transitionary species, climax species, post transitionary species and climax species is more intense, but there are more positive connection among the transitional species(including prior transitionary species, prior transitionary species and post transitionary species, post transitionary species) ,and the interspecific relationship is more stable relatively. (4)The main species in different succession process of pine oak forests community are respectively divided into 4, 5, 4 ecological groups. Above all, the interspecific relationship of main species in the succession process of pine oak forests community on the south-facing slopes in Qinling Mountains gradually become stable and concomitant. In practice, the reasonable adjustment measures of interspecific relationship can prompt the pine oak forests community on the south-facing slopes in Qinling Mountains more stable and healthier, effectively shorten the process of succession.

Abstract:In order to clone VdWRKY53 transcription factor from ‘Vitis davidii 0943’,reveal the relationships between its sequence signature,gene function and the resistance to white rot fungi and reveal the molecular regulatory mechanisms of resistant germplasm preliminary,we designed primers and cloned VdWRY53 of ‘Vitis davidii 0943’ based on the known homologous sequences VvWRKY53.Its expression was verified through bioinformatic analysis of genes,promoters and real-time fluorescence quantitative PCR after inoculating white rot fungi and spraying salicylic acid.The expression of WRKY53 can be monitored in both ‘Vitis davidii 0943’ and ‘Pinot Noir’ grape which inoculate white rot fungi or salicylic acid by real-time fluorescence quantitative PCR verification.The CDS and promoter of the Chinese wild grape ‘Vitis davidii 0943’ VdWRKY53 both have the resistance genes feature.At the same time VdWRKY53 is different from the ‘Pinot Noir’ grape and the nucleic and animo acids are also different.These differences may cause different functions.VdWRKY53 plays an important biological function in grape disease resistance by bioinformatic analysis and real-time fluorescence quantitative PCR.

Abstract:Full cDNA of one MADS-box gene,PrseSHP with GenBank accession No.GU362645,was cloned from Prunus lannesiana using homologous cloning and RACE method.The full length of PrseSHP cDNA is 1 223 bp，containing an open reading frame（ORF）of 741 bp and coding for a polypeptide of 246 amino acid residues.Sequence and phylogenetic analyses grouped PrseSHP into PLE/SHP lineages of the MADS-box family.Conceptual translation revealed that PrseSHP contain MADS,I,K and C domains.Expression analysis suggested that PrseSHP expressed mainly in petal,stamen,gynoecium and young fruit of P.lannesiana ‘Makino’.Moreover,functional analysis suggested that transgenic Arabidopsis was obviously dwarf,and flowering during 6-8 rosette leaves,which was early than that of wild-type Arabidopsis who was flowering during 14-17 rosette leaves.Ectopic expression of PrseSHP could obviously promote flowering of transgenic Arabidopsis.Our results suggest that PrseSHP are involved in flowering in Cherry Blossom.

Abstract:The gene FtAH4L,which encoding the autoinhibited H⁺-ATPase isoform 4 like(AH4L) involved into flavonoids transportation,was cloned from tartary buckwheat cultivar Xiqiao No.2(Fagopyrum tatarium).The length of FtAH4L gene was 3 398 bp,and the ORF(Open Reading Frame) was 2 898 bp encoding 966 amino acids.The molecular weight of FtAH4L was 109 kD,and its pI was 6.48.Conserved motifs and phylogenetic analysis demonstrated that AH4Ls are relatively conservative in different plant species.At the seedling stage of tartary buckwheat,semi-quantitative RT-PCR analyzed the expression profiles of FtAH4L gene,and AlCl₃ colorimetric method measured the total flavonoids content in cotyledons and hypocotyls,after jasmonates treatment and different lighting(White fluorescent,LED White,LED Blue,LED Red and UV-B).The results showed that FtAH4L expression and flavonoids content not only had a significant increase(P<0.05),but also showed a positive correlation in cotyledons and hypocotyls after jasmonates treatment.Under all the lightings,FtAH4L expression was unremarkable change(P>0.05) while flavonoids content was raised obviously in cotyledons.However,in hypocotyls,FtAH4L expression and flavonoids content were promoted notably(P<0.05) except LED Red.Particularly,LED blue and UV-B presented the extremely significant affect(P<0.01).This work could provide an important reference to understand the mechanism of FtAH4L gene involved in flavonoids transportation in tartary buckwheat.

Abstract:In this paper,we used normal embryo rice ‘Chao2-10’ and giant embryo rice ‘Shangshida No.5’ as materials.The embryo weight and mass ratio of embryo to brown rice of ‘Shangshida No.5’ were compared with those of ‘Chao2-10’.Then we did the genetic analysis of giant embryo phenotype.Giant embryo gene (GE) of ‘Shangshida No.5’,‘Chao2-10’ and Korea giant embryo rice ‘M-2-565-11-3-B(ge)’ were cloned to analyse their sequence.The expression levels of GE gene in ‘Shangshida No.5’,‘Chao2-10’ were analysed by Real time-PCR with the ‘Nipponbare’ as a control.The results were as follows:(1) Both embryo weight and mass ratio of embryo of brown rice ‘Shangshida No.5’ were significantly larger than these of ‘Chao2-10’ (P<0.01).However,embryo weight of the ‘Chao2-10’ is close to or more than some of the giant embryo rice cultivars reported previously;(2) Giant embryo phenotype of ‘Shangshida No.5’ is controlled by a single recessive gene,which is same to ‘M-2-565-11-3-B(ge)’;(3) GE gene in these three cultivars is also a new GE allele:‘Chao2-10’ has a mutation (ge^p) in the promoter;‘Shangshida No.5’ has mutations (ge^c) both in the promoter and CDS;‘M-2-565-11-3-B(ge)’ only has a mutation (ge^h) in CDS;(4) The expression pattern of the ge^c in young caryopses was different from other GE alleles reported,which increase steadily from 4 day to 7 day after flowering.This paper first reported two new GE alleles,one is mutated in the promoter,and the other has mutations in both promoter and CDS.

Abstract:The F₂ population was derived by crossing two diverse Cucurbita maxima lines ‘98-2-351’ and ‘06820-1’.Investigation and statistical analyses were conducted on rind and flesh color of mature fruits for parental plants and each generation.The results demonstrated that the orange and grey rind plants in F₂ population were fitted for the ratio of 3∶1,indicating that the grey rind was controlled by a single recessive gene;similarly,the yellow and white flesh plants in F₂ population were also fitted for the ratio of 3∶1,showing that the white flesh was controlled by a single recessive gene.With bulked segregation analysis and recessive-class approaches,two SSR markers PU078072 and PU013839 were detected to be tightly linked to the locus CmRc at a distance 5.9 and 14.5 cM,respectively.Meanwhile,one SSR marker PU132712 was founded to be closely linked to the locus CmFc at a distance 6.7 cM.This study laid the foundation for further screening the molecular markers closer linked to rind and flesh color genes of C.maxima and locating them accurately.

Abstract:We designed SCAR markers according to the markers linked to clubroot resistant gene in Chinese cabbage,in order to develop the new clubroot resistant materials of non-heading Chinese cabbage through marker-assisted selection (MAS).The results indicated that one pair primer among 8 showed polymorphism between parents of resistant and susceptible,and co-segregation with reported SSR marker and resistant characterization of F₂,suggested that it could be used to identify the clubroot resistance,named CRb-R-25.Based on the inter-subspecies hybrid,backcross and selection of CRb-R-25,TQ14-1-15 with clubroot resistance of non-heading Chinese cabbage was bred by introgression of resistance gene in Chinese cabbage.

Abstract:To investigate the mechanism of russet skin formation in pear (Pyrus bretschneideri Rehd.),we used the exocarp of the wild type ‘Dangshansuli’ and its mutant type ‘Xiusu’ pear with russet fruits at different days after full bloom (DAFB) as material in this experiment.The content of polyamine was determined by High Performance Liquid Chromatography (HPLC).The key genes in polyamine biosynthesis were cloned by rapid amplification of cDNA ends (RACE),and their physicochemical properties were conducted by the protocol of Protparam website (http://web.expasy.org/protparam/) and the phylogenetic tree of putative proteins was constructed by MEGA5.0 software.The relative expressions of ADC,SPDS and SPMS genes at different stages were analyzed by using real-time quantitative reverse transcription-PCR (qRT-PCR).The results showed that:(1)The putrescine contents in the exocarp of ‘Dangshansuli’ was significantly higher than that in ‘Xiusu’ except for 50 and 150 DAFB.At 75 DAFB,the contents of spermidine and spermine in the exocarp of ‘Xiusu’ were higher than that in ‘Dangshansuli’.(2)The genes of arginine decarboxylase (ADC),spermidine synthase (SPDS) and spermine synthase (SPMS) were cloned,and were submitted to the database of the National Center for Biotechnology Information(NCBI) with the accession number KM923903,KM923905 and KM923906 ,respectively.The structure of putative proteins of ADC，SPDS and SPMS gene in pear was closer to that in apple.ADC and SPMS were all water-soluble by the prediction of their physicochemical properties.The SPDS was water-repellent by the prediction of their physicochemical properties.(3)The levels of relative expressions of ADC,SPDS and SPMS in the exocarp of ‘Xiusu’ were higher than that in ‘Dangshansuli’ at 50 DAFB.It was postulated that the metabolism of polyamine and up-regulation of relevant genes may be associated with the formation of russet fruit of ‘Xiusu’ pear.

Abstract:In order to formulate conservation strategies of this species,We assessed the genetic diversity of G.littoralis with total 241 samples of 10 populations using molecular marker ISSR analysis.The result revealed that high levels of genetic variations occurred within and among populations (PPB=84.21%,Ne＝1.562 8,I^*＝0.866 3,h^*＝0.342 5).The genetic differentiation coefficient (G_ST) among populations was 0.205.Analysis of molecular variance (AMOVA) demonstrated that 25.91% of genetic diversity was found among populations,74.09% of genetic diversity was found within populations.The value of gene flow (N_m) was 1.939 1.It is indicated that the endangered status of this species is probably due to destruction of habitats of the wild populations,rather than a loss of the genetic diversity.

Abstract:Chromosome preparation and carbol fuchsin dyeing were adopted to examine the meiosis process of pollen mother cells and the development of male gametophytes of Atractylodes japonica for providing a scientific basis for further study of the A.japonica cytogenetics .The results are as follows：（1）The meiosis process of A.japonica pollen mother cells is closely correlated with the bud size,related to the buds 4~12 mm when entering meiosis.（2）There are difference in the stages of meiosis in the same bud and anther.（3）Meiosis normal tetrads accounted 85.14% with a cross-shaped main .（4）The percentage of abnormal meiosis is 7.71% and a series of abnormal phenomena in meiotic division of pollen mother cells such as chromosome fragments,lagging chromosomes,chromosomes bridges,asynchronization of chromosomes segregation,deviant tetra and so on are obserued.（5）During the development of the male gametophytes,mitosis took place two times.The mature pollens were 3-cell ones with 3 germ furrows in appearance.This research aimed to provide scientific evidence for cytogenetics of A.japonica.Studies suggest that the unsynchronization of the meiosis for different anther in the same flower bud extended its flowering period and increase the chances of pollination,which was an evolution of adaptation to the environment.It was one of the main reasons of partial pollen abortion that the chromosome bridges,lagging chromosomes,chromosome fragments,polyad and other anomalies in meiosis.

Abstract:The reaction characteristics of histocytology in interaction between potato with horizontal resistance and Phytophthora infestans were examined using general microscopy and electron microscopy.Microexamination results showed that:(1) Hypersensitive response (HR) was observed in horizontal-resistance potato after inoculation and hyphae were restricted within the cells infected.Fewer branches of hyphae and haustoria were formed.(2) The spreading trend of invaded cells,more haustoria and hyphae branchses were found in susceptible cultivar.(3) The electron microscopy observation showed that a series of abnormal changes occurred in intercellular hyphae,haustorial mother cells and haustoria in the resistant potato cultivar.The cytoplasm became more electron-dense and numbers and sizes of vacuoles increased.The cell walls of hyphae and haustorial mother cells were thickened irregularly.The organelles were distributed disorderly in the cytoplasm and the shapes of haustorial mother cells and haustoria became abnormal.Finally,the intercellular hyphae,haustorial mother cells and haustoria became necrotic and collapsed.The structural defense reactions such as formation of cell wall deposition which made cell wall thickened extremely or papillar structures in the inner site of host cell wall were also observed in the resistant potato.

Abstract:Structural characters of leaf epidermis of 20 wild Lilium species were examined by the optical microscope and the scanning electron microscopy.The results showed that:(1) The stomatas of 20 wild lilies are all distributed in abaxial epidermis of their leaf epidermis,which are parallel to the cells of abaxial epidermis ,and located in the endpoint of abaxial epidermis cells.They have no accessory cells,and their guard cells are kidney.The type of guard cells cuticle is striate,and the types of epidermis cells cuticle are smooth or striate.The epidermis cells of all species have waxes which have two types,membranous platelets and platelets.There are significant differences between species in stomata density,size of stomata and leaf cells,pattern of anticlinal walls;(2) L.davidii var.willmottiae,L.davidii,L.lancifolium,L.nepalense,L.papilliferum,L.duchartrei,L.pumilum,L.taliense,L.fargesii,L.concolor var.pulchellum,L.dauricum were clustered in the first group and L.sulphureum,L.regale,L.amoenum belong to the second group while L.tsingtauense formed a distinct group,L.leucanthum,L.leucanthum var.centifolium ,L.sargentiae,L.brownii var.viridulum,L.brownii were clustered in the fourth group using clustering analysis which is accordance with structural characters of leaf epidermis;(3) Structural characters of leaf epidermis play important taxonomic value in distinguishing between different wild lilies.

Abstract:The micromorphological features of pericarp surface (MFPS) in 20 species of Ligusticum and 1 species of Conioselinum in China were observed under SEM for the first time,and the transection anatomical characteristics of mericarps of 15 species of which were also studied in this paper.The result shows that MFPS,such as the smoothness and the visibility of epicarp cell,the types of ornamentation and epidermal secretions,exhibit rich diversity.The number of vittaes,the shape of ribs and endosperms were markedly different,which were evaluated as the significant references for inter-species identification and relationship discussed.From previous micromorphological,anatomical and molecular studies on Apiaceae,we concluded that:(1)Ligusticum was an artificial genus.(2) According to the MFPS and fruit anatomical characteristics,the results do not support Ligusticopsis as a natural genus.(3) In this paper,the taxonomic status and genetic relationships of some Ligusticum species were investigated.

Abstract:By optical microscopy and scanning electron microscopy,we examined the microscopic structure features of secretory tissue in the leaves and stem surface and transverse section of Empetrum nigrum,using steam distillation,solvent extraction-steam distillation and solvent extraction extracting the volatile components of E.nigrum,by GC-MS method we analyzed the volatile components.The results show:(1)the glandular trichomes and secretory cells are E.nigrum secreting tissue.Oil cells in the pith of stem was yellow-brown color,glandular trichome in the leaf surface,it composed of 1 basal cell,a stalk cell 1-3,1-4 head cells.(2)The steam distillation and solvent extraction-steam distillation extraction rate was lower,but the smell similar to the original plants.There are a total of 10 ingredients,more aromatic odor,solvent extraction method extraction rate was higher,but a lot of impurities.(3)Three different methods contain volatile oil composition of compounds:2-furanmethanol,5-ethenyltetrahydro-π 5- trimethyl-,cis and 2-pentadecanone,6,10,14-trimethyl.27 and 32 compounds were identified from parts of stem and leaf of E.nigrum.There were 15 common components in the identified ones,mainly including tetratriacontane,nonacosane and naphthalene,1,2,3,4,4a,5,6,8a-octahydro-7-methyl-4-methylene-1-(1-methylethyl)-,(1π4aπ8aπ)- and so on.Studies suggest that secretory tissue is closely related to E.nigrum aroma matter creation.The composition and content of aroma discharge has important influence.It is the organic combination of these aromatic chemical composition and its growth and environmental factors to the formation of the characteristic flavor of the E.nigrum.The results of this study can provide reference for the research of development and utilization of this spice resource.

Abstract:The anatomical structure of leaf conducting tissue and photosynthetic characteristics of alfalfa (Medicago sativa L.) were studied based on two nitrogen forms (nitrate nitrogen and ammonium nitrogen) and five nitrogen levels (0,105,210,315,420 mg·L^-1).Two cultivars,‘Gannong No.3’ and ‘Longdong’,were selected as materials,and the experiment was conducted outdoors (in flashing net room) using sand culture method.The results showed that:(1) Compared with non-nitrogen treatment,the anatomical structure of leaf conducting tissue of both alfalfa cultivars changed significantly under both nitrogen treatments.The vascular bundle area,xylem area,phloem area and vessel numbers of leaf conducting tissue increased significantly.The photosynthetic rate,stomatal conductance,leaf area and chlorophyll content also increased significantly (P<0.05),and the maximum number occurred at nitrogen level 210 mg·L^-1.(2) Compared with NO₃^--N treatment,the vascular bundle area,xylem area,phloem area,vessel number,photosynthetic rate,stomatal conductance,leaf area and chlorophyll content increased more under NH₄⁺-N treatment.(3) Compared with cultivar ‘Longdong’,the vascular bundle area,xylem area,phloem area,vessel number,photosynthetic rate,stomatal conductance,leaf area and chlorophyll content performed better in cultivar ‘Gannong No.3’.The data showed that nitrogen can improve the anatomical structure of leaf conducting tissue and photosynthetic characteristics of alfalfa by increasing photosynthesis.The combination of NH₄⁺-N and 210 mg·L^-1 performed best in all treatments.The anatomical structure of leaf conducting tissue was improved,the vascular bundle was the biggest,both phloem and xylem showed largest area and developed well,and the number of vessel was also the largest;and ‘Gannong No.3’ performed better than ‘Longdong’.

Abstract:To select lianas with high tolerance to Mn polluted soil and further study its physiological mechanisms on Mn resistance,We studied Ficus pumila,Lonicera japonica,Parthenocissus quinquefolia,Trachelospermum jasminoides in soil containing 3 000 mg/kg (T₁),6 000 mg/kg (T₂),9 000 mg/kg(T₃) and 12 000 mg/kg (T₄) Mn,with the soil was not added Mn as the control.The effects of different concentrations of Mn stress on biomass,mass growth,different parts of the Mn content,chlorophy content,malondialdehyde (MDA) content,the activities of superoxide dismutase (SOD),peroxidase (POD) and catalase (CAT) in four lianas were studied,and their tolerance indexes (Ti),translocation factors (TF),bio-concentration factors (BCF) were analyzed.The results are as follows:(1) With the increase of Mn concentration in soil, the biomass and mass growth mostly were declined,average tolerance index of F.pumila,P.quinquefolia,L.japonica and T.jasminoides was 82.48%,84.86%,89.21% and 95.41%,respectively; (2) The general trend of Mn content in aboveground parts and roots were increased with the increase of Mn concentrations in soil,and the Mn content in roots were always higher than that in aboveground parts ,the TF values were less than 1 and the average BCF of aboveground parts and roots from high to low were as follows:T.jasminoides＞L.japonica＞P.quinquefolia＞ Ficus pumila; (3) Chlorophy content was mostly decreased with the increase of Mn concentration in soil,MDA content was continuously increased,and the activities of SOD,POD,CAT were firstly increased and then decreased.Chlorophy content and three antioxidant enzymes activities decrease as well as MDA content increase of T.jasminoides were the lowest among four lianas when treated with T₄.The study revealed that Mn tolerance,transfer and accumulation abilities of T.jasminoides were the highest in four lianas，suggesting it is potential use in Mn tailings soil bioremediation.

Abstract:To understand the salt tolerance mechanisms of two Glycyrrhiza species,we examined the response of root to Na⁺ and changes of vascular tissues under NaCl stress.Glycyrrhiza inflata and Glycyrrhiza uralensis seedlings were cultured with a complete Hoagland nutrient solution containing 0,50,100,150,200 and 250 mmol·L^-1 NaCl for 21 days.Then,the dry weight,root diameter,K⁺ and Na⁺ content in different parts of plants,K⁺/Na⁺ and selective absorption and transportation coefficients(SA_K,Na,ST_K,Na) were measured.The vascular tissue of root was also observed.(1)There were different effects of NaCl on seedlings of two Glycyrrhiza species.The dry weights of G.inflata and G.uralensis at 250 mmol·L^-1 NaCl were 53.34% and 46.21% that of no NaCl stress,respectively.It indicated that G.uralensis had relatively lower salt tolerance.(2)Compared with other part of plant,more Na⁺ accumulated in root of G.inflata with increased NaCl concentration,suggesting that root has good interception effect on Na⁺ that from outside salt environment.This interception effect was limited for G.uralensis because it can be only observed at 0-150 mmol·L^-1 NaCl.(3)G.inflata had more greater SA_K,Na and ST_K,Na values of root than those of G.uralensis at same NaCl concentration,implying a stronger selective transport capability for K⁺ of root while Na⁺ was inhibited from being transported to stem.For these reasons,the significant difference of salt tolerance occurred in two Glycyrrhiza species.(4)The ratio of vascular tissue area to total root area of G.inflata and G.uralensis were increased at 250 mmol·L^-1 and 150-200 mmol·L^-1 NaCl,respectively.It displayed the root anatomical adaptation,which contributes to enhancement of transportation capability of root and alleviation of salt injury.

Abstract:To obtain tissue-cultured plant,We used Tamarix chinensis seeds as materials and established their sterile solated culture system by tissue culture method.A stress condition was formed through adding different concentrations of NaCl (0,50,80,100,120,150 and 200 mmol/L) to the medium (MS+1.0 mg/L 6-BA+0.1 mg/L NAA).To explore the physiological mechanism of T.chinensis tissue-cultured plant response to NaCl-stress,We investigated the changes of activities of T.chinensis tissue-cultured plant antioxidases,contents of osmotica,plasma membrane permeability and production rate of super oxygen anion (O^-·₂) under different concentrations of NaCl-stress.The results indicated that:(1)The activities of superoxide dismutase (SOD) and peroxidase (POD) of T.chinensis tissue-cultured plant were rising and then going down as concentrations of NaCl-stress were increasing,and both at 100mmol/L NaCl-stress reached a maximum,whereas,the activity of ascorbic acid peroxidase (APX) was gradually declining.(2)The contents of osmotica such as free proline (Pro),soluble protein (Pr) and soluble sugar of tissue-cultured plant were gradually rising and significantly higher than that of the concurrent control as concentrations of NaCl-stress were increasing,and at 200 mmol/L concentration notably increased 53.77%,47.38% and 67.65%,respectively.(3)The production rates of hydrogen peroxide (H₂O₂) and super oxygen anion (O^-·₂),content of malonic dialdehyde (MDA) and plasma membrane permeability of tissue-cultured plant were all gradually rising and significantly higher than that of the concurrent control as concentrations of NaCl-stress were increasing,and at 200 mmol/L concentration notably increased 36.42%,58.71%,82.60% and 42.54%,respectively.The study confirmed that antioxidases system of T.chinensis tissue-cultured plant showed favorable active oxygen scavenging activity under a low concentration of NaCl-stress (≤100 mmol/L) and the osmotica played positively regulated functions under different concentrations of NaCl-stress.Accordingly,T.chinensis showed a strong salt tolerance.

Abstract:In this paper，we used Dendrobium officinale protocorm as materials and studied the impact of low temperature (4 ℃) ,exogenous NO (NO donor SNP),NO scavenger (cPTIO) and nitric oxide synthase inhibitors(PBITU) on NO content,the sucrose synthase (SS) activity,and the content of polysaccharide,sucrose,fructose,glucose in D.officinale protocorm to clear the relationship between low temperature and endogenous NO in the course of polysaccharide synthesis.The results showed that:(1) Under the low temperature (4 ℃) treatment,the NO content significantly increased,the SS activity enhanced and the content of sucrose,fructose,glucose and polysaccharide increased in D.officinale protocorm.SNP(0.5 mmol·L^-1) treatment had the similar effect to the low temperature (4 ℃) treatment;under the low temperature (4 ℃) treatment,the SS activity and polysaccharide content increased after a lot of NO produced,sucrose accumulated earlier than fructose and glucose.(2) 4 ℃+SNP treatment could significantly improve the SS activity,and the content of NO,sucrose,fructose,glucose,polysaccharide in D.officinale protocorm.They were significantly higher 68.04%，96.20%，60.69%，45.64%，66.90% and 67.03% than that of control group,and the effect was better than that in low temperature (4 ℃) or SNP separate treatments.(3) PBITU could partially inhibit NO production in D.officinale protocorm which induced by low temperature (4 ℃) and the inhibition rate was 77.15%;it also inhibited the promotion of the SS activity,polysaccharide synthesis and the accumulation of sucrose,fructose,glucose in D.officinale protocorm which induced by low temperature (4 ℃).(4) Under SNP+cPTIO and 4℃+cPTIO treatments,the SS activity and the content of sucrose,fructose,glucose,polysaccharide and NO in D.officinale protocorm had no significant difference with the control group.Studies had shown that the low temperature and exogenous NO could promote polysaccharide synthesis in D.officinale protocorm,and low temperature induced NO production,the SS activity exaltation and polysaccharide content addition were associated with NO production.In D.officinale protocorm,NO is a necessary signal molecule for its polysaccharide synthesis.

Abstract:With Lycium barbarum L.cv.Ningqi No.1 as material,using high performance liquid chromatography (HPLC) technology,we determined different development period of L. barbarum L.fruit sugar (Fructose,Glucose,Sucrose and Starch) content in different regions (Yinchuan in Ningxia,Baiyin in Gansu and Delingha in Qinghai).At the same time,we monitored the meteorological factors during development of fruit in different regions to discuss the effect of main meteorological factors on sugar accumulation in L. barbarum L.fruit.The results showed that:(1) During the fruit development period of L. barbarum L.,the mean temperature and the temperature difference between day and night of different regions presented the change trend of Yinchuan>Baiyin>Delingha,while the mean light intensity presented YinchuanL. barbarum L.fruit was given priority to with accumulation of hexose (glucose and fructose),sucrose and starch content rarely.The content of hexose in the ripe fruit was in the order of Delingha>Yinchuan>Baiyin.(3) The meteorological factors that affected sugar content of L. barbarum L.fruit in Yinchuan region mainly were mean temperature,daytime mean temperature and mean temperature difference,and in Baiyin region mainly were mean temperature difference,temperature during the day and mean light intensity also had a certain influence,while in Delingha region mainly were mean temperature difference,mean light intensity and daytime mean temperature.This research suggested that higher mean temperature and mean temperature difference in Yinchuan and stronger mean light intensity and longer light hours in Delingha were conducive to L. barbarum L.fruit hexose accumulation.Meteorological factors limited the sugar accumulation of L. barbarum L.fruit mainly were bigger relative humidity and weaker light intensity in Baigin region.

Abstract:We studied the effects of light(continuous light,12 h light/12 h dark,and continuous dark),temperature(10/15 ℃,15/20 ℃,20/25 ℃,25/30 ℃,30/35 ℃,and 35/40 ℃),drought(0,-0.1,-0.2,-0.4,-0.6,-0.8,-1.0,-1.2,-1.4,and -1.6 MPa)and salt(0,0.05,0.10,0.20,0.30,0.40,0.60,and 0.80 mol/L)stress conditions on the seed germination of Populus euphratica,aims to reveal the seed germination sensibility of P.euphratica towards different temperature,light,salt and drought stresses,and reveal the ecological adaptation mechanisms of P.euphratica seed germination.The results showed that:(1)P.euphratica seeds germinated under variable temperature(10 ℃/15 ℃~30 ℃/35 ℃)and three different light conditions(continuous light,continuous darkness and 12 h light/12 h dark),their final germination percentage were more than 77%.The optimum temperature range among three light conditions were 25 ℃/30 ℃ to 30 ℃/35 ℃,and the seeds germinated rapidly and intensively,and three light conditions had no significant effect on seed germination.(2)P.euphratica seeds could germinated under the osmotic stress from -1.4 to 0 MPa,and there was no significant differences among osmotic stress treatments range from -1.0 to 0 MPa,with higher final germination rates,which was more than 90%.However,the seed germination process and germination rate were affected significantly under osmotic stress less than -0.4 MPa,and when osmotic stress less than -1.2 MPa,seed germination was significantly inhibited.(3)P.euphratica seeds could germinated in 0～0.80 mol/L NaCl solution,while the seed germination rates and final germination percentage of P.euphratica saw a decreasing trend along with the increasing salt concentration from 0 to 0.80 mol/L,there was no significant difference in treatments of 0 to 0.20 mol/L.Seeds germination rates,seed germination process and germination ratio were affected significantly when salt solution concentrations were higher than 0.2 mol/L.The results demonstrated that P.euphratica seeds germination characteristics of a broad germination temperature,without strict requirements of light,germinated quickly and intensively under optimum temperatures,and tolerance of salt and drought stresses could help seeds germination quickly under limits of water resource.There was an important ecological adaptation of P.euphratica seed germination to regeneration in arid desert.

Abstract:The carbon and nitrogen composition and stable isotope abundance of plants collected from the alpine meadows and seeded pasture at the headwater region of the Yellow River were analyzed with mass spectrometer Isoprime100.The purpose was to determine the type of plant photosynthesis and response of carbon and nitrogen stable isotopes abundance to vegetation succession.The results show that:(1)plant carbon content of 58 species varies between 28.64% and 51.55% and nitrogen content is from 0.89% to 4.04%.The δ¹³C abundance varies between -29.50‰ and -24.69‰ and the δ¹⁵N value is from -4.57‰ to 8.32‰.(2) The plant carbon content of different sites is in the order of mix-seeded pasture (45.54%)>non-degraded meadow (43.18%)>light degraded meadow (42.18%)>heavily degraded meadow (39.68%).The plant nitrogen content of different sites is in the order of non-degraded meadow (2.30%)> mix-seeded pasture (2.28%)>light degraded meadow (2.13%)> heavily degraded meadow (2.10%).(3) The δ¹³C values of plants in mix-seeded pasture,non-degraded meadow,light degraded meadow and heavily degraded meadow are -25.63‰,-26.57‰,-26.76‰ and -27.91‰,respectively,and the δ¹⁵N values are -0.63‰，0.32‰，2.76‰ and 0.26‰,respectively.Alpine degradation can result in decreased plant carbon and nitrogen content.All species analyzed are C₃ plants and no C₄ and Crassulacean acid metabolism (CAM) plants were found.The low annual mean temperature may be the main factor restraining the distribution of C₄ plants.The δ¹³C values decrease with degradation,but the δ¹⁵N values have no such tread.

Abstract:To reveal the complex relationships between the characteristics of interspecific association and community succession in the succession process of pine oak forest community on the south-facing slopes in Qinling Mountain.Based on 2×2 contingency tables,we used the variance ratio,χ² test,Jaccard index and Spearman’s rank correlation coefficient to study the characteristics of interspecific association and correlation among main plant populations of different successional stages in the successive serials from Pinus tabulaeformis forest to P.tabulaeformis-Q.aliena var.acuteserrata mixed forest then to the subsequent Q.aliena var.acuteserrata forest on the south-facing slopes in Qinling Mountain.The results showed that:(1)the overall interspecific associations of dominant species in P.tabulaeformis forest,Q.aliena var.acuteserrata forest and P.tabulaeformis-Q.aliena var.acuteserrata mixed forest are significant positive connection,each community has a relative stability.(2) The positive and negative interspecific associations and correlation percent of main species in P.tabulaeformis forest and P.tabulaeformis-Q.aliena var.acuteserrata mixed forest are smaller,and their community stability are inferior to Q.aliena var.acuteserrata forest.(3)Interspecific competitions among pioneer species,pioneer species and prior transitionary species,climax species,post transitionary species and climax species are more intense,but there are more positive connection among the transitional species(including prior transitionary species,prior transitionary species and post transitionary species,post transitionary species) ,and the interspecific relationship is more stable relatively.(4)The main species in different succession process of pine oak forests community are respectively divided into 4,5,4 ecological groups.Above all,the interspecific relationship of main species in the succession process of pine oak forest community on the south-facing slopes in Qinling Mountains gradually become stable and concomitant.In practice,the reasonable adjustment measures of interspecific relationship can prompt the pine oak forest community on the south-facing slopes in Qinling Mountains more stable and healthier,effectively shorten the process of succession.

Abstract:In this paper,the floristic relationships between Bailangshan and other flora were analyzed.Based on Plot survey,floristic spectrum,cluster analysis and principal coordinates analysis(PcoA),I investigated the elements of seed plants in Bailangshan and the similarity of others flora.The results showed that:(1)it is abundant in wild species in Bailangshan,the types of distribution are various and complex.790 species in 101 families and 394 genera were identified,Angiosperm accounted for 98.35% of the total of seed plants.It is notable in dominant family phenomenon,Oligotypic and monotypic genera are abundant,which show some relict.(2)A total of 273 temperate areal-types that accounted for 81.3% of seed plants genera,The types of geographical distributing composition are various and complex,temperate floral elements are dominant,which have something in common with tropical flora.The present data indicated Bailangshan should belong to North China flora and the region should belong to the East Asia zone representing the feature of transition from warm temperate to temperate areal-types.(3) Floristic correlation between Bailangshan and Nuluerhushan,Donglingshan are significant at the 0.01 level,and the coefficients are 0.999 and 0.998,respectively.Based on two-dimensional scatter plot of PcoA and dendrogram based on the floristic spectrum,the similarities were obvious between Bailangshan and Nuluerhushan,Xiaowutaishan,Donglingshan and Wulingshan of the 12 moutains in this study.The hydrothermal and heterogeneous condition is an important determining factor in geographical distribution pattern.

Abstract:To provide the basis of ecology and biodiversity conservation in coastal islands,We conducted floristic spectrum,diversity index,principal coordinate analysis and cluster analysis to reveal distribution patterns and floristic relationships of coastal islands (chose from Bohai,Huanghai,Donghai and Naihai in different latitude area) in China.Results showed that:(1) with the decrease of latitude,a decreasing trend can be observed on the proportions of temperate elements at genus-level,while those of tropical elements showed contrary patterns,which may be strongly corelated with their different ecological characters and energy distribution;(2) Compared with other coastal islands,floristic Shannon index (1.887-2.197) and Simpson index (0.780-0.865) have no obvious difference.Pearson correlation is significant at the 0.01 level by correlation analysis,and the coefficients are between 0.199 and 0.997.(3) Two-dimentional scatter plot of PcoA and cluster dendrogram based on the floristic spectrum demonstrated floras of 22 coastal islands were divided into 5 groups,North-south latitude distribution pattern and similarity of the floristic of 22 coastal islands in China was revealed accordingly.

Abstract:Based on the investigation and identification of bryophytes in Longshou Mountain and the surrounding wetlands from Yongchang County,Jinchang City,Gansu Province,one newly recorded genus and four newly recorded species of Pottiaceae in Gansu Province are reported.They are Pterygoneurum Jur.,P.ovatum (Hedw.) Dix.,P.subsessile (Brid.) Jur.,Tortula atrovirens (Smith) Lindb.and Desmatodon cernuus (Hueb.) Bruch & Schimp.respectively.The voucher specimens are deposited in the Herbarium of Inner Mongolia University (HIMC).

Abstract:Taxithelium kerianum(Broth.)Broth.(Pylaisiadelphaceae,Bryophyta)from Guangxi was found and firstly recorded in China.Morphological descriptions and illustrations of T.kerianum were provided.Key to the species of Taxithelium was given and differences between T.kerianum and other species of the genus Taxithelium distributed in China were discussed.As a typical tropic mosses,T.kerianum mainly distributes in South Asia and its nearby areas.

Abstract:During studies on the specimens of Rhizocarpon collected from Mt.Tianshan and August First Forest Farm,we found Rhizocarpon atrovirellum,R.furax and R.simillimum are new to China.The detailed taxonomic descriptions with photos are provided for the three species.

Abstract:The genus Pleopsidium is new to the flora of Ningxia.A new record species Pleopsidium gobiense was identified and characterized using morphological and molecular methodology,described and illustrated based on these data.P.gobiense is sensitive to human disturbance.

Abstract:Salicylic acid,as a well-known signal molecule,has significant effects on various physiological processes,such as respiratory metabolism,seed germination,floral induction,senescence,and stress resistance.In recent years,great progress has been made on its effects on photosynthesis.Salicylic acid has the ability to regulate stomatal movement,photosynthetic pigment content,photosynthetic machinery and carbon assimilation,and may display different effects with different concentrations,plant species,and environments.Centering on stomatal movement,photosynthetic pigment content,photosynthetic machinery and carbon assimilation,this paper summarized the research progress on the effects of salicylic acid on photosynthesis.