Abstract:To study the precise roles of cytosol GAPDH in plant response to salt stress,we obtained 1 381 bp HcGAPDH from Chenopodiaceae uhalophyte Halostachys caspica with RACE technology.The ORF(open reading frame) of which encode 314 amino acids.HcGAPDH gene displayed considerable homology with known members of the GAPDH protein family.The expression of HcGAPDH is upregulated by salt stress and abscisic acid treatment.Green fluorescent protein- tagged HcGAPDH was localized in cytosol of the transgenic Arabidopsis thalinana cells,and could transfer into nucleus under salt stress,which is independent of carbohydrate- mediated signaling.Our results implicate that HcGAPDH function in plant cells through modulating cytosol to nucleus-signaling cascade under salt stress.The study laid a certain foundation for elucidation of salt-tolerance mechanism of Halostachys caspica at molecular level.

Abstract:The shikimate/quinate hydroxycinnamoyltransferase (HCT) gene involved into lignin synthesis was cloned by RT-PCR from wild Cryptotaenia japonica Hassk from Guizhou Province.In this paper,the expression profiles of CjHCT under different temperature treatments have been analyzed and explore suitable temperature of artificial cultivation of C.japonica Hassk.The results showed as follows:(1)CjHCT gene contains 1 290 bp nucleotide acids,which encodes 429 amino acids.Using DNAMAN software prediction,the molecular weight and pI of CjHCT were 47.58 kD and 6.67,respectively.Phylogenetic analysis demonstrated that CjHCT showed the highest identity with HCTs from Apiaceae family plants.(2)Quantitative real-time PCR analysis showed that the expression of CjHCT gene was different in root,petiole,leaf,and flower of C.japonica Hassk.The expression level of CjHCT gene was the highest in root and the lowest in leaf.The expression levels of CjHCT gene were similar in leaf and flower.(3)The expression profiles of CjHCT gene was analyzed under 10 ℃,18 ℃,30 ℃ and 38 ℃ temperature treatments for 0,0.5,1,2,4,8,12,and 24 h.The expression level of 0 h treatment which was used as control was treated as 1.Under high temperatures (30 ℃ and 38 ℃) treatments,the CjHCT gene showed the highest expression levels at 0.5 h.The expression level of CjHCT under 30 ℃ treatments is higher than that under 38 ℃ treatments at this time.Under low temperature (10 ℃ and 18 ℃) treatments,the CjHCT showed the highest expression level at 12 h.The expression level of CjHCT under 10 ℃ treatment for 0.5 h is lower than that of control.The highest expression levels of CjHCT under high temperature (30 ℃ and 38 ℃) treatments are higher than that under low temperature (10 ℃ and 18 ℃) treatments.The CjHCT under high temperature (30 ℃ and 38 ℃) treatments showed the highest expression levels earlier than that under low temperature (10 ℃ and 18 ℃) treatments.C.japonica Hassk is an edible vegetable.In order to improve the taste,the lignin contents in C.japonica Hassk should be reduced.This study aims to choose the optimum temperature for C.japonica Hassk cultivation by cloning CjHCT and analyzing its expression profiles under the different temperatures.And at the same time,this paper provides novel insights into the condition of C.japonica Hassk cultivation.The experiment is a preliminary study that low temperature treatment inhibits the expression of CjHCT gene and provides the reference for suitable temperature of artificial cultivation for C.japonica Hassk.

Abstract:In this study,we report the molecular characteristics of four ADH genes MaADH1 (GenBank No.KM253748),MaADH2 (GenBank No.KM253749),MaADH3 (GenBank No.KM253750) and MaADH4 (GenBank No.KM253753) cloned from the banana plant (Musa acuminate L.AAA group,cv.Cavendish) using RACE based strategy.At the nucleotide acid level,these genes share a sequence high similarity with ADHs in the banana DH-Pahang (AA group) genome.Phylogenetic analysis showed that the deduced amino acid sequences of MaADH2,MaADH3 and MaADH4 belong to the first class,MaADH1 does not belong to the first and third classes.Expression analysis by semi-quantitative RT-PCR revealed that these genes were differentially expressed in various tissues.In addition,their expression was regulated by various stress conditions,including exposure to ABA,ethylene,JA,SA,cold,salinity,drought,flood and Fusarium oxysporum f. specialis(f.sp) cubense Tropical Race 4 (Foc TR4).The results showed that MaADH2 was strongly induced by ABA,ethylene,JA,SA,drought and flood,the maximum relative expression is 19.14,428.19,68.21,61.79,53.73 and 108.43 respectively.The MaADH3 was strongly induced by NaCl and its maximum relative is 220.27.MaADH1 and MaADH4 were induced by four hormones,abiotic stress and biotic stress,but the expression quantity change was little.This study demonstrated that the MaADH2 was found to be a potential marker gene of ABA,ethylene,JA,SA,flood and drought stress in the banana,the MaADH3 was found to be a potential marker gene of salt stress in the banana.

Abstract:Cinnamyl alcohol dehydrogenase (CAD) plays a key role in lignin biosynthesis.In this study,we report the molecular characteristics of CAD gene cloned from banana (Musa acuminata L.AAA group,cv.Cavendish) using a RACE-PCR-based strategy.MaCAD1 contained an open reading frame of 1 077 bp which encoded a polypeptide of 358 amino acids.Protein alignment showed that it contains the complete typical conserved alcohol dehydrogenase domains,which belongs to a typical CAD protein.Phylogenetic analysis showed that the deduced amino acid sequence of MaCAD1 also has high similarity to OsCAD6 (CAD39907) from rice.Tissue-specific studies showed that the expression of MaCAD1 was constitutively expressed in various tissues of banana seedling.In resistant and susceptible varieties of banana after inoculation Foc TR4,the expression of MaCAD1 was decreased.While in resistant varieties the time point of MaCAD1,compared to control,increased higher than that in susceptible varieties at time points,indicated that this gene played an important role in banana resistance.MaCAD1 could be a new marker gene in banana seedling under the infection of Foc TR4.

Abstract:Plant hormone brassinosteroid (BR) can improve the drought resistance of plant.This study explores the effects of spraying BR on the expression of transcription factor BES1/BRI1 in cotton seedling under drought stress.It is helpful for elucidating the mechanism of BR improving the drought resistance of cotton.The BES1/BZR1 gene was cloned by using PCR technique from the seedling of cotton‘XLZ17’(Gossypium hirsutum) and named as GhBES1/BZR1 (GenBank accession number KP272000).Sequence analysis indicated that GhBES1/BZR1 contains an open reading frame (ORF) of 960 bp,which encodes 319 amino acids included a conserved domain DUF822.The calculated molecular weight is 34.3 kD and the theoretical isoelectric point is 8.95.After 2.5% PEG-6000 treatment for 24 h,water,BR (brassinosteroids) and Z (BR inhibitor) were sprayed on the seedlings of cotton‘XLZ17’,respectively.The effects of spraying BR on the expression of GhBES1/BZR1 were analyzed by the real time quantitative PCR(qRT-PCR).The results showed that the expression levels of GhBES1/BZR1 were greatly increased after BR spraying within 3 h,and then the expression levels of GhBES1/BZR1 were significantly decreased after 6 and 12 h.The results demonstrated that spraying BR quickly up-regulated the expression of GhBES1/BZR1 under drought stress,which might be contributed drought resistance of cotton.

Abstract:‘Wink’ (fertile),‘Zhongshanhong’ (male sterile),‘Wink seedling-3’,‘Wink seedling-12’ were examined.The flower characteristics,pollen viability,pollen shape and the cytological features of microspores were observed,DYT1,TDF1 and MYB4 genes that was related to the tapetum development were analyzed.The semi-sterile characteristics of the ‘Wink seedling-3’ and ‘Wink seedling-12’ were identified preliminarily,and the pattern of the gene regulation of pollen abortion was studied.The results indicated that:(1)the main features of two ‘Wink seedling’ grapes:filaments curl and shorter than the style,few pollen in the anther,the pollen viability was only about 10%.There were two kinds of pollen grains in anthers:normal prolate spheroidal pollen grains and approximately spheroidal pollen grains.(2)The anther wall structure was not obvious,and the microspore mother cells were few and loose in the ‘Wink seedling’ grapes.The tapetum of ‘Wink seedling-3’ did not degrade completely in the binuclear stage,the nutrients of tapetum could not supply for the development of spores timely,which caused the abortion of microspores in the late developmental stage.The tapetum of ‘Wink seedling-12’mostly disintegrated at the early mononuclear microspore,which caused the abnormal supply of nutrient and the abortion of microspores.(3)In the meiosis stage,DYT1 and TDF1 expression in ‘Wink’ were the highest,MYB4 was the lowest;These three gene expression in ‘Zhongshanhong’ were contrary to ‘Wink’,and the levels of two ‘Wink seedling’ grapes laid between ‘Wink’ and ‘Zhongshanhong’.After the mononuclear microspore stage,three gene expression in ‘Wink’ were always low,DYT1 expression levels were the highest,TDF1 and MYB4 were the lowest;TDF1 and MYB4 expression levels in ‘Wink seedling-3’ were highest in the mononuclear microspore stage,and TDF1 expression in ‘Wink seedling-12’ was highest in the binuclear stage.The study showed that ‘Wink seedling-3’abnormal tapetum degradation was probably related to the DYT1 insufficient expression in the meiosis stage,the TDF1 overexpression in the mononuclear microspore stage,and MYB4 unusual expression in the mononuclear microspore stage.‘Wink seedling-12’abnormal tapetum degradationwas probably related to the DYT1 insufficient expression and MYB4 overexpression in the meiosis stage,and the TDF1 overexpression in the binuclear stage.

Abstract:To identify the differences among hybrid lines from ‘MB09’בLongshu 7’ in DNA level and cytogenetical level,we used parent materials as contrast,and analyzed DNA fingerprint characteristic of 20 excellent hybrid lines (F₁ clone generation) with SSR molecular marker technology,and the pollen fertility and chromosome configuration at meiosis metaphase Ⅰof pollen mother cells (PMCMⅠ) of 8 selected outstanding hybrid lines (F₁ clone second generation) with regular slide-preparing technique and microscopy examination method,which could provide for hybrid breeding of excellent potato strains on the basis of the molecular cytology.The result showed that:(1) two suitable SSR primers C57 and S25 were screened for fingerprint establishment,and a SSR fingerprint was obtained by PCR amplification,which could identify 20 hybrid lines and their parents;(2) the pollen fertility rate of hybrid excellent lines 1,2,7,11,13,14,15 and 20 ranged from 36.73% to 87.08% in addition line F_1-7(87.08%) was the highest and significantly higher than the parent(83.33%),which had some differences;(3) chromosome configurations at PMCMⅠ of the 8 hybrid lines were obviously different,which include univalent,bivalent,trivalent and quadrivalent ,and the bivalent rate of 8 hybrid excellent lines ranged from 49.13% to 82.91% and line F_1-7 was the highest.The study illustrated SSR fingerprint character for 20 good potato hybrid lines and differences of pollen fertility and chromosome configuration for 8 excellent lines.

Abstract:Allium tubiflorum and A.neriniflorum (Allium L.) are two species whose perianth segments were connated at base into a tube.As typical representatives of the East Asian endemic plants,they are the ideal models to study the changes of temperate deciduous forest.Genetic diversity across 14 and 16 populations of A.tubiflorum and A.neriniflorum was analyzed using ISSR molecular markers.(1)At the species level,total percentage of polymorphic loci (PPB) of A.tubiflorum was 98.00%,Nei’s gene diversity (H) was 0.264 8,and Shannon’s information index (H_o) was 0.415 3.For A.neriniflorum.PPB,H and H_o were 95.56%,0.253 9 and 0.399 8,respectively,little lower than the values of A.tubiflorum.There were lower genetic variations at population level.The coefficient of genetic differentiation (G_st) of the two species were 0.421 8 and 0.430 1,and analysis of molecular variance (AMOVA) demonstrated that among populations component accounted for 38.95% and 39.17% of the total variation,and that most genetic diversity was present within population.(2)Combined the results of this study and previous cytology information,hybridization and polyploidization may be the evolutionay driving force of A.tubiflorum and A.neriniflorum.Meanwhile,the two species had asexual reproduction with bulb,to overcome fertility decline and lower number of individuals within population.Complex genetic background and diversity reproduction might be an important factor leading significant genetic differentiation within population.(3)The previous phylogenetic information and UPGMA analysis in this study showed A.tubiflorum and A.neriniflorum were sister groups and had close genetic relationship.Overlap regions of the distributions of the two species located between Taihang Mountains and Yan Mountains,and this regions may be their ancestor’s distribution.There were abundant genetic variations among populations in the overlap regions.For this reason,the regions near Taihang Mountains and Yan Mountains might be the differentiated center and genetic diversity center of the two species.

Abstract:The anatomy of entophyte system of Arceuthobium sichuanense was observed with paraffin sectioning and light microscope.The endophytic system consisted of cortical strands within the bark and sinkers embedded in the xylem.The cortical strands extended by squeezing the cortex cells of host.When penetrating the periderm of host,the cortical strands developed aerial shoots;when contacting with and near to the secondary phloem of host,the cortical strands developed sinkers.Then,the sinkers penetrated the phloem and cambium of host,extended to the xylem and grew along with the xylem rays of host.The periderm of host became thickened when the penetration pegs and the cortical strands penetrated it.The number of host cortex cells increased where localized infection of A.sichuanense occurred.The results indicated that A.sichuanense can develop systemic infection and reflected the interaction between A.sichuanense and host at histopathological level.

Abstract:In order to reveal the reason for low fruit setting rate of a new very precocious loquat line ‘Chuanzao loquat’ in the first florescence,we adopted the method of field experiment to observe flowering stage of ‘Chuanzao loquat’ in the first florescence.Stigma receptivity was measure by benzidine-H₂O₂,pollen vitality was tested by TTC method and pollen tube growth was observed by aniline blue staining method in this study.Results showed that:(1)The first florescence of 'Chuanzao loquat’ to enter beginning bloom stage was mid-July and full bloom stage was from late July to early Aug.The final bloom stage was from mid-Aug.to late Aug.The highest,lowest and average air temperature in the first florescence was 34.9 ℃,18.9 ℃ and 26.03 ℃,respectively.(2) The stigma with receptivity was on 0-4 d after flowering.The stigma with very strong receptivity and pollen with the highest viability was on 1 d after flowering,then the pollen viability rapidly reduced.(3)Pollen tubes had arrived in style base at 48 h and entered the ovule at 96 h after self-pollination,but very few.Accordingly,the combination of many factors such as short duration of stigma strong receptivity,pollen viability decreased rapidly,very few pollen tubes which could arrive at style base and enter the ovule and high temperature was the important reason of low fruit-set rate of ‘Chuanzao loquat’ in the first florescence.

Abstract:We investigated the leaf stoma morphology and quantitative characteristics of 29 dicotyledonous plants in the Tibetan Plateau grasslands by means of optical microscope and analyzed the significant difference among stoma index,which provided experimental basis for revealing the mechanism of adaptation to alpine environment and exploring auxiliary classification of stoma.The results showed that:(1) Most stoma randomly arranged on both upper and lower epidermis and stomatal apparatus was irregular type.(2) The average stomatal length(SL) of upper and lower epidermis were 26.20 μm and 25.56 μm,which was smaller,but stomatal density(SD) and stomatal index(SI) were relatively higher.(3) There were significant difference among various families,genera and species on SL,SD and SI.(4)There were significant correlation between six stomatal quantitative characteristics.(5) SL and SD of upper epidermis were significantly associated with families,genera and species.Other stomatal characteristics of lower epidermis except for SI were significant correlated with plant varieties.We came to the conclusion that the distinctive morphology and quantitative characteristics of leaf stoma of dicotyledonous plants in the Tibetan Plateau grasslands reflected the long-term adaptation to alpine environment and quantitative characteristics of stoma had important value in plant auxiliary classification.

Abstract:Most of Epimedium species are commonly used Chinese medicine that it is difficult to identify medicinal material and classification.Pollen morphology,size and exine ornamentation from 31 species of the genus Epimedium were examined using the scanning electron microscope.Results showed that：(1) The pollen shapes are mostly prolate.The minority of them are spherical with the size of (15.5-25.0) ×(27.3-48.1)μm and polar views are mostly trifid circular,with three hole groove.(2)There are three kinds of pollen grains with reticulate,article reticulate or striped exine ornamentation.(3) The study suggests that the exine ornamentation of pollen grains,among each species,would be different in shape and size of the mesh and surface characteristics of the net ridge etc.This study provided some new evidences for the plant taxonomy and the identification of medicinal materials of Epimedium.

Abstract:Knowledge of the basic breeding characteristics of endangered plants is critical and particularly important to develop successful conservation strategies.Here,we investigated the flowering characteristics,pollination adaptation and mating system of a rare and endangered plant,Bergenia scopulosa,using artificial pollination experiments and field observations in natural and ex-situ conservation populations.The results showed that:(1)the flowering span of the population,infloresence and single flowering were approximately 4 months,30 d and 15 d,respectively.The life span of single flower would prolong 3-5 d and the corolla closed when low temperature or rain and snow occurred.(2)Pollen viability achieved the maximum within 12 h after anther dehiscence in the first flowering day (about 90%) and maintained more than 30% about 6 d.Stigma shown acceptance in the first 9 days during the anthesis and kept the maximum in the first 1-4 days.(3)The main effective pollinator was Apis cerana cerana.The average visiting frequency of effective pollinator was 6.5 flowers·min^-1 and single flower residence time was (11.0±4.8) s.(4)The pollen-ovule ratio (P/O) was 589.8 and the outcrossing index (OCI) was 3.The results of artificial pollination experiments exhibited that B.scopulosa was self-compatible with autonomous selfing rarely happening,and reproductive success relied on pollinators without apomixes.The research suggested that the breeding system of B.scopulosa was facultative xenogamy and inbreeding depression played a role in the process of fertilization.

Abstract:In this study,a salt tolerant variety VAO-9 was used to analyse leaf cDNA library of oat treated with 300 mmol/L NaCl by Illumina sequencing and in silico expression profile.At the same time,relative conductivity,MDA,and proline content of leaves under 0(CK),100,200,250 and 300 mmol/L NaCl stressed were determined,probed the relationship between the differentially expressed of genes and physiological response to salt stress.The results showed that:(1)transcriptome sequencing get 65 801 Unigenes,and the gene expression in oat transcriptome showed high nonhomogeneity and redundancy.FDR value ≤0.001 and log₂ Ratio≥2 as the selection criteria when identify and analyze differentially expressed genes (DEGs),compared with the control,there were 306 and 64 genes up-and down-regulated expressed respectively coercion 0.5 h;coercion 3 h,there were 639 genes up-regulated,290 genes down-regulated;stressed 24 h,1488 genes up-regulated and 882 genes down-regulated.(2)The KEGG pathway analysis indicated there are 23 652 unigenes comparison to the 128 KEGG metabolic pathways,including abiotic stress-related pathways,such as plant hormone signaling pathways,ABC transporter protein pathway,inositol phosphate pathway,osmotic adjustment,and so on.The changing trends of the physiological indicators(relative conductivity,MDA,and proline contents in oat leaves) were the same as the differentially expressed genes under 300 mmol/L NaCl stressed,which indicated that the amount of differentially expressed genes is closely related to the physiological responses.Thus,salt tolerance genes expression can be judged according to the physiological indicators of plant salt response.

Abstract:In this study,we integrated the mapping information based on collecting of positioning information about QTLs related to cadmium accumulation in soybean grains.Then the recombinant inbred line(RIL) population(F_6:7) derived from ‘Zhonghuang24（ZH24）’ and ‘Huaxia3(HX3)’ were used to validate one major QTL Cda1/Cd1 which controlled the cadmium accumulation in soybean grain.The results showed that the major QTL Cda1/Cd1,which were mapped by two groups,actually located in the same fragment on chromosome 9.The point mutation in GmHMA1,that one of the candidate gene for Cda1,was similar in ZH24 and HX3.The Cda1 was not linked with the differences of cadmium concentration in various organs between ZH24 and HX3.The findings indicated that there were other new QTLs controlling the difference of cadmium accumulation in grain between ZH24 and HX3.It is necessary to make genome-wide scanning and identification in future.

Abstract:In order to clarify the mechanism of deficient phosphorus stress on phosphorus absorption of flue-cured tobacco,taking ‘Yuyan No.10’ as the material,we designed a pot experiment with two treatments,which were no phosphate fertilizer application and recommended amount of phosphate fertilizer.The expression differences of high-affinity phosphate transporter genes NtPht1;1(PT1) and NtPht1;2(PT2) between two treatments and the correlation of genes expression and phosphorus accumulation in leaves and roots at later growth stages were analyzed.The results showed that:(1)with the advancement of the growth stages,the relative expression of PT1 and PT2 genes,the dry matter weight and the phosphorus accumulation in leaves and roots of flue-cured tobacco increased gradually and the content of phosphorus in leaves decreased.Whereas,there was no significant pattern in roots.(2)The relative expression of PT1 and PT2 genes were up-regulated under deficient phosphorus stress.The relative expression of PT1 gene in leaves was higher than that in roots,while PT2 gene was the opposite,comparatively.(3)The accumulation of dry matter and phosphorus in flue-cured tobacco were limited under deficient phosphorus stress.At 90 days after transplanting,the dry matter weight and phosphorus accumulation in tobacco roots and leaves with no phosphate fertilizer application were less than half the values of the phosphorus application treatment.There were extremely significant differences among treatments at 0.01 probability levels.This might imply that the up-regulated expression of PT1 and PT2 genes under deficient phosphorus stress was due to the decrease of phosphorus accumulation in tobacco tissues rather than the low available phosphorus soil.

Abstract:Xinjiang apricot fruits (Saimaiti) were sprayed with 0.05% chitosan oligosaccharide(COS) with molecular weight 5000 Da in four periods:fruit setting period,fruit enlarging period,color turning stage and 48 h before1 picking.The post-harvest apricot fruits after being innoculated were stored at 4 ℃,90%-95%RH.The lesion diameter and inoculation incidence of apricot fruits inoculated with Alternaria alternata.The activities of defense related enzymes including phenylalanine ammonia-lyase (PAL),β-1,3-glucanase (GLU) and chitinase (CHT) and the contents of lignin,hydroproline-rich glycoprotein(HRGP) were measured regularly.Effects of preharvest chitosan oligosaccharide-induced resistance to black spot in fruits and contents of HRGP and lignin in cell wall was studied.The results showed that disease incidence and lesion diameter were lower in chitosan oligosaccharide-treated fruits compared with their respective controls at the end of storage.The activities of PAL,CHT,GLU and the contents of lignin and hydroproline-rich glycoprotein in chitosan oligosaccharide-treated fruits were showed the change trend:rise after the fall，and was significantly higher than their respective controls in the same period.The activities of PAL,CHT,GLU and the contents of lignin and hydroproline-rich glycoprotein in chitosan oligosaccharide-treated fruits reached the peak at 21^th day,28^th day,21^th day,28^th day,14^th day.Moreover,all of peak were 12.17%,78.22%,31.41%,34.81% and 77.44% higher than their respective controls.The above results indicated that pre-harvest chitosan oligosaccharide can induce the disease resistance of apricot fruit treated by improving the disease related protein,HRGP and the content of the cell wall.

Abstract:With‘Zhugenjiang’ ginger (Zingiber officinale Roscoe) as the object of study,we analyzed the physiological and biochemical mechanism of MeJA induced to the disease resistance.The research discovered that the treatment of exogenous Methyl jasmonate(MeJA) could significantly reduce disease indices of ‘Zhugenjiang’ ginger,and increase resistance against Bacterial Wilt of Ginger.no directly inhibitory effect was detected on pathogenicity of Ralstonia solanacearum in vitro.MeJA-treated ‘Zhugenjiang’ ginger could speedly promote endogenous H₂O₂ content during the early stage,and simultaneously induce the increases of activities of phenylalanine ammonialyase(PAL),peroxidase(POD),polyphenol oxidase(PPO),catalase(CAT),chitinase and β-1,3-glucanase associated with increase of lignin content.The results exhibited that MeJA regulated the downstream signaling molecule H₂O₂ level to enhance activities of enzymes related to defense and expressions of pathogenesis-related proteins(PR proteins) in ginger cells,resulting in promoting lignin accumulation and furthermore improving disease resistance in ginger.

Abstract:In order to explore the drought tolerance of Rhododendron latoucheae in seed germination and seedling growth stage,we studied the effects of drought stress on seed germination,growth,cell membrane permeability,malondialdehyde(MDA) content,the organic osmoregulation substances and antioxidant enzyme activities by choosing dry seeds and seedlings with 90 d age and using different concentrations of polyethylene glycol(PEG-6000) simulated drought stress.The regression analyses were done between seed germination,early seedling growth and PEG stress.The results showed that:(1)the initial germination time of R.latoucheae seeds was delayed with the increasing of drought stress degree in 5%-25% PEG range,and the germination duration was prolonged.The seed germination rate,germination potential,germination index,vigor index and early seedling growth were all significantly reduced.The seed could not germinate absolutely at severe drought stress(25% PEG).(2)The changes of seed germination rate,germination potential,germination index,vigor index and early seedling growth were showed very significant negative correlation with the degree of drought stress.The regression equation between seed germination,early seedling growth and PEG stress showed that the half lethal PEG drought stress concentration was 15.68%,while the semi dwarfing PEG drought stress concentration was 15.37%.(3)With the increase of PEG concentration,SOD activity of R.latoucheae seedling leaves increased firstly and then decreased,but were significantly higher in all the stress treatments than that of CK(0% PEG).Cell membrane permeability,MDA content,proline content,soluble sugar content,POD and CAT activities increased significantly in moderate(15%-20% PEG) and severe drought stress,and the changes of these indexes were showed very significantly positive correlation with the degree of drought stress.The research found that seed germination and seedling growth of R.latoucheae were significantly inhibited by drought stress,and cell membrane was also damaged in different degrees.Thus it could be seen that R.latoucheae increased contents of the osmoregulation substances and antioxidant enzyme activities in vivo to adapt to drought stress environment at the same time,making the inhibition and damage degree to the minimum.

Abstract:We used Buchloe dactyloides.ramets as materials to research physiological metabolic response of B.dactyloides.leaves active oxygen scavenging system to differences photoperiod response.Clonal ramets were labeled as O (old sister ramet) and Y (young sister ramet),then we set connective group and disconnected group.O ramet and Y ramet were connected through the internode in connective group,whereas the internodes were cut off in disconnected group;the light cycle of O ramet was set for light 12 h/dark 12 h in both two groups,instead,light cycle of Y ramet was set for 12 h darkness/12 h light (just opposite to O ramet).And the activities of superoxide dismutase (SOD),peroxidase (POD),catalase (CAT),ascorbate peroxidase (APX),and malondialdehyde (MDA) content of ramet leaves were continuous measured 48 h illumination after cultivation of 7 d differences photoperiod treatment and 72 h stable illumination conditions.The results showed that after one weeks of different photoperiod treatments,under continuous light conditions,SOD,POD,CAT,APX activities and MDA content in disconnected ramets of B.dactyloides.leaves basically showed the opposite variation trend within 24 h.However,SOD,POD,CAT,APX activities and MDA content in connected ramets of B.dactyloides.leaves presented convergence of variation trend within 24 h.It indicated that reactive oxygen species scavenging system of B.dactyloides.showed rhythmic expression patterns,and B.dactyloides.connected ramets reactive oxygen species scavenging system tends to be synchronized under different photoperiod treatments.

Abstract:In this study,we tested the response of black locust (Robinia pseudoacacia L.) with instantaneous and continuous mechanical damage to the arbuscular mycorrhizal (AM) fungi,and using three-partments system tested the role of common mycorrhizal networks (CMNs) in transmitting mechanical damage related signal between black locust seedlings.We set seedlings with a leaf cut and with a leaf cut every 3 days as the instantaneous and continuous mechanical damaged treatments,respectively,and tested the POD,PAL activities at 0-138 h and growth of the seedlings.Meanwhile,we used three-partments system with 25 μm nylon net to test POD and PAL activities of receptor plants after the donor plants suffered the instantaneous and continuous mechanical damage.The results showed that AM fungi can promote root growth and improve the ratio of transplanting survival of the seedlings with continuous mechanical damages.Suffering from instantaneous mechanical damage,the activities of L-phenylalanin ammo-nialyase (PAL) and peroxidase (POD) increased for 90 h and then decreased.Also,the PAL and POD activities of mycorrhizal seedlings were significantly higher than that of the non-mycorrhizal seedlings.And CMNs can transmit signals relating to mechanical damage,resulting in alteration of PAL and POD activities of donor plants.

Abstract:Independent measurements of sap flow in stems of Haloxylon ammodendron,Nitraria tangutorum and Calligonum mongolicum and environmental variables using a commercial sap-flow gauges and micrometeorological monitoring system,respectively,were made to study nighttime sap flow activities and its influencing factors,and to estimate the nighttime water consumption for an H.ammodendron stand in an oasis-desert ecotone,located in the middle range of Hexi Corridor,Northwest China.(1)Nighttime sap flow density for these species was high before 0 oclock and decreased quickly,it was weak and fluctuated dramatically between 0 oclock and 6 oclock.We found nighttime sap flow densities between these species were very significant (P<0.01),and the mean value for H.ammodendron,N.tangutorum,and C.mongolicum was 3.73,1.12,and 6.07 g·cm^-2·h^-1,respectively.The results showed that sap flow density of three species all decreased in typical rainy days.(2)The total nighttime water use for these species was close related to the stem diameter during the study period (R²=0.92),and it was not significant difference between different months (H.ammodendron,P>0.05;N.tangutorum,P>0.05;C.mongolicum,P>0.05).We found that H.ammodendron contributed 1% to 30% nighttime water use to daily total water,N.tangutorum contribute 0.1% to 16%,and C.mongolicum conribute 1.5% to 20%,respectively.(3)We presumed that nighttime sap flow for these species were mainly used to refilling because VPD and wind speed only explained 24%,25% and 27% of their variation,respectively.

Abstract:Using the Lotus Mountain as the study area,with typical plots methods,we investigated the species composition of different levels of stand structure,population structure and species diversity of Cyclobalanopsis glauca community under the slight,intermediate and severe human disturbances.The species richness index (S),Shannon-Wiener index (H),Simpson index (H′) and Pielou index (J_sw) were adopted to comprehensively evaluate the level of species diversity in C.glauca community.The results showed that:(1)a total of 161 vascular plant species belonging to 83 families and 134 genera were observed across the 9 explored plots within an area of 3 600 m²,and Gramineae,Lauraceae,Fagaceae,Theaceae are the dominant plant;(2)plant communities vary under different degrees of human disturbance effects.Trees are mainly in low diameter class (diameter at breast height<8 cm) and low height class (37 m) in arborous layer under sight and intermediate disturbances,suggesting a potential capacity of natural regeneration.Trees in low diameter and low height classes are rare under serious disturbance,and the community structure is unstable with a low primary productivity;(3)the important values vary significantly under different degrees of human disturbances,while dominant species show insignificant differences under these disturbances with a simple species composition Machilus microcarpa is the predominant species in shrub layer under severe disturbance,while herbaceous species are the dominant plants under intermediate disturbance;(4)S,H,H′,and J_sw decreased with the increases of human disturbance,indicating a decrease for plant biodiversity as a whole.

Abstract:The Altai Mountain is situated in the heart of Asia on the state borders between China, Russia Federation, Mongolia, Kazakhstan and has good ecological environment and rich in plant resources.Based on consulting of specimen and filed investigation, the difference in species, composition and areal types of seed plants of China Xinjiang Altai Mountain, Russia Altai Mountain,Mongolia Altai Mountains and Kazakhstan Altai Mountains were compared and similarity of seed plants among four regions was analyzed.Results showed that:(1)The resources of wild seed plant are rich in the four Altai Mountain.Descending by the richness in turn:Russia Altai Mountains＞ Mongolia Altai Mountains＞ China Xinjiang Altai Mountains＞ Kazakhstan Altai Mountains.(2)Family and genus containing 1 and 2-10 species predominate at family and genus level in the four places.(3)The areal type of family of seed plants in four Altai Mountain is mainly Cosmopolitan and N.Temp.types, and at the genus level it is mainly N.Temp.Types.，Cosmopolitan， OW Temp.，Medit., W.As.to C.As.Types.(4) Similarity coefficient of seed flora in four Altai Mountain regions at family and genus levels is more than 50％, which meant the high similarity of seed plant flora between each other.It is suggested that there are difference in the four places of Altai Mountain.The Altai Mountain of China Xinjiang as a bridge for the all flora contacts, mix and serve.

Abstract:The effects of trifluralin and pendimethalin concentration and treatment time duration on the cluster buds of wild Lilium sargentiae(2n=2x=24) in vitro were investigated.With sterile water (CK) and colchicine as control,we soaked L.sargentiae adventitious shoots in different concentration (100,200,300 μmol/L) herbicide (trifluralin,pendimethalin) solutions for 12 h,24 h and 36h,respectively.The chromosome number and stomata guard cell of leaf hypodermis and morphology characteristics of leaf were studied.The results indicated that the treatment of materials in pendimethalin solution at 300 μmol/L for 36 h lead mutation rate of 30.0%,200 μmol/L trifluralin soaked 36 h,mutation rate of 32.2%.The two kinds of mutagens treatment induced mutation and survival rates were not significant.Mutants identified by cytology to find the two kinds of mutagens treatment are able to induced mutation.Compared with colchicine,the mutagen processing time is short,material mortality is low,mutation rate is high,damage to humans and animals is less and cost is low.Compared with the diploid plants,in the size of stomata in tetraploid plants significantly increased and stomatal density decreased significantly.The study considers the herbicide pendimethalin and trifluralin can be used as a substitute of colchicine to induce polyploidy,and the stomatal size can be used as an effective indicator for polyploidy initial rapid detection.

Abstract:Based on detailed collection and identification of bryophytes,we discovered two new geographic distribution records of Leptodontium pungens and Syntrichia amphidiacea.L.pungens is discovered in China for the first time.It is superficially well distinguished by the hyaline layer.More constant features include the absence of a stem central strand and a differentiated epidermis over the costa.Frequently collected on volcanos and páramos at high altitudes,mainly distributed in Mexico,Central American,Andes,Juan Fernandez,southern Brazil and Africa.S.amphidiacea was firstly found in Inner Mongolia.The peculiar character of this species is that there are abundant cylindrical gemmae on the dorsal and ventral surfaces of leaf apices.The species has been reported from Eastern North America,Mexico,Central America and Guizhou Province of China.Morphological characteristics and geographical distribution of L.pungens and S.amphidiacea are discussed.Meanwhile the illustrations are provided.The present study increased the basic data of Chinese moss flora.

Abstract:The species Gastrodia gracilis is reported as a new record from Chinese mainland,which is discovered in Beige country,Kaiyuan,Yunnan.The plants live in evergreen broad-leaved forest (altitude is about 2 500 m) whose crown density is larger,environment is wet.Its raceme is about 6 cm long,flowers laxly arranged,tubular,drooping,light brown.Apex of perianth tube 5-lobed,floral bracts persistent;Rhizome is small.It is native to Taiwan,China and Japan.This report strengthens the relationship between the flora of Yunnan and Taiwan,China,Japan flora.

Abstract:The rare and endangered species Diplandrorchis sinica is reported as a new record of Loess Plateau,China,and it is the first report outside the type locality in Liaoning Province.

Abstract:In order to counteract the invasion of pathogenic microorganisms,plants have evolved a set of immune system to recognize the pathogens and mount defense.The plasma membrane-tethered pathogen recognition receptors (PRRs) and the cytoplasmic NB-LRR immune receptors are responsible for the recognition of the conserved features of pathogens.Following the recognition,the transportation of signals between nucleus and cytoplasm requires the presence of nucleocytoplasmic transport proteins to help the immune proteins and/or their associated signal carries to pass through the nuclear pores.Notably,some types of pathogen effectors,such as transcription activator-like (TAL) effectors,have also been found utilizing the host nucleocytoplasmic transport system to enter nucleus and to activate the expression of host susceptibility genes.In this review,we summarized the recent progresses of nucleocytoplasmic transport in plant innate immunity,including the mechanism of it,the require of plant immunity to it and some protein related to it in plant immunity,to demonstrate its importance in disease resistance.