Abstract:The RT-PCR combined with RACE method was used to clone the complete cDNA sequences and DNA sequences of plant-specific transcription factor DlGRAS4 and DlGRAS54 from embryogenic callus of Dimocarpus longan.The complete cDNA sequence of DlGRAS4 was 1 668 bp,encoding 431 amino acids,the complete cDNA sequence of DlGRAS54 was 2 113 bp,encoding 552 amino acids.DNA sequence analysis indicated that 5′-UTR of DlGRAS54 has a 1 533 bp intron.The sequences of both nucleotides and amino acids of the two members were high homologous with those of the known GRAS genes in other species.DlGRAS4 and DlGRAS54 located in plasma membrane;they had no signal peptide,had transmembrane structure and the GRAS protein domain.Anglicizing phylogenetic tree of GRAS in plants indicated that DlGRAS54 and AtPAT1,VvPAT1,PtPAT1,GmPAT1 belonged to the same branch;DlGRAS4 and AtSCL23,ZmSCL23 belonged to the same branch.Therefore,they putatively belonged to GRAS family.qPCR results indicated that DlGRAS4 showed approximately a “W” curve,it expressed at the highest levels in the globular embryos and cotyledonary embryos cultures.DlGRAS54 showed approximately an “M” curve,it expressed at the highest levels in the globular embryos and topedo embryos cultures,suggesting that DlGRAS4 and DlGRAS54 play a major role at the middle and late developmental stages of longan somatic embryogenesis.DlGRAS4 and DlGRAS54 showed up-regulated expression patterns under exogenous GA₃ treatment showed that they made the positive response with GA₃ treatment.

Abstract:The aim of this paper is to acquire genes related to the stress response in banana.A stress associated protein gene was acquired from banana roots cDNA library by randomly sequencing,which was named MaSAP1 (GenBank accession number:AGH14257.1).The sequence amplified from banana root cDNA was the same with fragment sequences of plasmid OZ092 in library,indicating that MaSAP1 was a full-length cDNA,containing a 510 bp of the largest open reading frame,encoding 169 amino acids.The homology alignment of protein sequence found to contain complete A20 and AN1 motif.Phylogenetic analysis indicated that the MaSAP1 was closer with Oryza sativa and Aeluropus littoralis.Tissue-specific expression study showed that the expression of MaSAP1 was higher in the roots and fruits,the lowest in the stems.Real-time PCR analysis showed MaSAP1 in response to hormone treatment,and also in response to various stress,such as drought,low temperature,high salt and FocTR4.Altogether the results in this work demonstrated that MaSAP1 may play an important biological role in plant growth and development,and plant response to different stress types.

Abstract:In this study,a Populus tomentosa cytosolic APX gene,named as PcAPX,was identified and characterized.The recombinant PcAPX protein,encoding a 249-residue protein with a calculated mass of 33.01 kD,showed high activity towards ascorbic acid (AsA) and H₂O₂.At fixed H₂O₂ concentration,the K_m and V_max values were (0.71±0.03) mmol·L^-1 and (0.41±0.02) mmol·L^-1·min^-1·mg^-1 for AsA.And at fixed AsA concentration,the K_m and V_max values were (0.60±0.21) mmol·L^-1 and (0.35±0.12) mmol·L^-1·min^-1·mg^-1 for H₂O₂.These data showed that the protein was active with AsA and H₂O₂ and had high catalytic efficiency.Real-time PCR analysis showed that the expression levels of PcAPX was higher in the mesophyll of aged leaves than that of other tissues.This research provided the theoretical support to investigate roles of APX gene family in plant growth regulation.

Abstract:An unknown protein gene related to somatic embryogenesis had been discovered and named Dimocarpus longan unknown protein gene 3 (DlUP-3) during the proteomic analysis of early somatic embryogenesis in longan.It was cloned by using degenerate oligonucleotide primers together with RACE.The full-length cDNA sequence of DlUP-3 gene was 1 681 bp.It contains a 1 017-nucleotides-long open reading frame (ORF) which encoded a protein of 338 amino acid residues (GenBank No.GQ167202).Bioinformatics analysis showed that the molecular weight of DlUP-3 protein is 36 854.2 Da with pI 9.05,it is a member of the Ras protein superfamily,which has ATP/GTP-binding site motif A (P-loop) binding site,Ras_like_GTPase superfamily module,hydrophilic characteristics and transmembrane properties but no signal peptide.Random coils are the most maximum structural elements and were found spreading in the whole polypeptide chain.The expression of DlUP-3 gene was also investigated during longan somatic embryogenesis according to the results of real-time quantitative PCR.Its expression was the lowest at the the friable-embryogenic callus stage and the highest at globular embryos stage.There had an elementary understanding to the important function of DlUP-3 gene during longan somatic embryogenesis,especially at globular embryos stage.This result laid a foundation for the further study on the function of DlUP-3 gene during longan somatic embryogenesis.

Abstract:Zinc finger protein plays important roles in plant stress tolerance.OpZFP,A zinc finger protein gene of Olimarabidopsis pumila,was isolated by homologous sequence cloning method.The open reading frame of OpZFP gene was 684 bp,encoding 227 amino acids which containing a typical Cys2/His2 zinc finger domain,an EAR-motif at its C-terminal region.Phylogenetic analysis revealed that OpZFP had a closer relationship with AtZFP1 and AlZFP1.A OpZFP promoter sequence covering 2 095 bp upstream of transcription start site was isolated from O.pumila,and showed only 84.4% similarity with that of AtZFP1 gene promoter.Several different cis-elements were found analyzed in two promoters.Expression analysis by semi-quantitative RT-PCR indicated that OpZFP displayed a much broader expression range in different tissues in O.pumila,with a maximum expression in root.OpZFP gene was induced by high salt,drought and low temperature,suggesting that the function of OpZFP might involve in some stress related signal pathways.

Abstract:‘Qindao 2’,‘Xiangnuo Q33’ and ‘Qingxiangnuo’ as the donor parents of resistance gene,were selected to cross with ‘Hongxuenuo’ in order to improve the Hongxuenuos’ resistance to rice stripe virus;Meanwhile the polymorphism of three molecular markers consisted of ST10,H21 and STS11-43 were separately analyzed among the parents,and the polymorphic markers were detected in the different F₂ populations.The results showed that:(1)The polymorphism of molecular markers were different among the parents.The markers ST10 and STS11-43 were just detected between ‘Hongxuenuo’ and ‘Xiangnuo Q33’,and the marker H21 was detected between ‘Hongxuenuo’ and ‘Qindao 2’ or ‘Hongxuenuo’ and ‘Xiangnuo Q33’ or ‘Hongxuenuo’ and ‘Qingxiangnuo’.(2)From different kinds of molecular markers’ detection results to different hybrid combinations,it can be found that some individuals of F₂ generation have had the resistance gene,while few individuals had heterozygous resistance gene.(3)The performance of each plant in the field estimates that all of the individuals containing resistance gene are resistant to rice strip disease,which is accordant to the expected result of molecular detection;but to those plants containing heterozygous resistance genes,it still needs further 2~3 generations’ examination to get the pure resistance gene.In conclusion,this research demonstrated that the results of molecular assisted selection and the resistance of each plant in the field are consistent and those three different markers could be used to detect the resistance genes in the progenies of different hybrid combinations,which provided a viable method for modifying the Hongxuenuo’s resistance to rice stripe virus.

Abstract:The genetic diversity of the 29 accessions of Pennisetum longissimum var.intermedium from Gansu and Yunnan were analyzed by ISSR makers.The results showed that:(1)10 primers were selected from 50 primers which had clear,stable polymorphic bands.A total of 72 loci were obtained,including 62 polymorphic loci.On average,amplification site of each primer was 7.2 and the percentage of polymorphic loci (PPL) was 87.4%.The mean observed number of alleles (Na),effective number of alleles (Ne),Shannon information index (I) and Nei’s genetic index (H) were 1.861 1,1.742 8,0.561 0 and 0.395 9,respectively.The genetic similarity coefficient (GS) ranged from 0.236 to 0.903,which shows rich genetic diversity among the materials of P.longissimum var.intermedium.(2)Cluster analysis with UPGMA method showed that the 29 tested accessions were divided into 4 groups at the level GS 0.51,but there was no correlation (r=0.437 0,P=0.204 6) between genetic and geographic distance among the germplasms studied.The results of this research were the first time to reveal genetic diversity and variation of P.longissimum var.intermedium at the molecular level,which provided theoretical and data evidence for the introduction,domestication,conservation and exploitation of wild P.longissimum var.intermedium germplasm resources.

Abstract:Eighteen populations of Melilotus alba and Melilotus officinalis were used to study the genetic diversity by ITS and trnL-trnF sequences.The results showed as followings:(1)The aligned length of trnL-trnF sequences was 459 bp and there were 6 parsimonious informative sites,6 variable sites and 33.1% G+C content.The aligned length of ITS sequence was 714 bp and there were 4 parsimonious informative sites,6 variable sites and 48.9% G+C content.(2)All Melilotus L.populations could be divided into two groups in the phylogenetic tree of trnL-trnF,which showed that trnL-trnF sequence had the identify ability in the molecular phylogeny study of Melilotus L..(3)The genetic diversity of M.officinalis was higher than that of M.alba in both sequences by analyzing haplotypes and nucleotide diversity.

Abstract:The cross-compatibility between Primula forbesii (Sect.Monocarpicae.Ex Pax ) and P.saxatilis (Sect.Cortusoides Balf.f.) was investigated by seed-setting and observation of pollen tube behavior after interspecific crosses.The results showed that no normal seeds were obtained from reciprocal crosses between the two Primula species.The pollens of P.forbesii were able to germinate at the stigma surface of P.saxatilis in 4 hours after pollination.However,pollen germination significantly lagged behind the control groups [P.saxatilis (P)×P.saxatilis (T),P.saxatilis (T)×P.saxatilis (P)] and the pollen tube elongation was hindered so that the pollen tubes could not extend into the ovary in 192 hours after pollination.The pollens of P.saxatilis germinated successfully at the stigma surface of P.forbesii and the pollen tubes elongated into the ovary in 48 hours after pollination.The pre-fertilization barriers was observed in P.saxatilis×P.forbesii,while P.forbesii×P.saxatilis showed good interspecific compatibility,and the hybrid seedlings have been attained by embryo rescue.The length of stigmas may be one of the factors that influence the compatibility of interspecific hybridization.

Abstract:Using the paraffin sectioning,histochemistry and visible-spectrophotometry,we investigated the structures of vegetative organs(root,stem and leaf),and compared the accumulation localizations and contents of saponins and flavonoids in Bupleurum scorzonerifolium Willd.The results showed that:(1)The root consisted of periderm,pericyclic parenchyma tissue and secondary vascular tissue.The stem was composed of epidermis,cortex and vascular bundles.The leaf was isobilateral one.The vegetative organs all possessed characteristics adapting to arid environment.(2)Histochemical localization results showed that saponins distributed in vascular cambium,secondary phloem and partial pericyclic parenchyma cells in secondary xylem of the root;In the stem,they distributed mainly in epidermis,cortex,vascular cambium and secondary phloem;In the leaf,they distributed in the epiderm,spongy and palisade.In the stem,flavonoids were located in epidermis,collenchyma lie in angularity and partial cortex cells;In the leaf,they were located mainly in the epidermis and the collenchyma lied in the leaf margin and the lower epidermis.And there were small amounts in the root.(3)The results of phytochemical tests showed that the contents of saponins in the root,stem and leaf were 2.635%,1.045% and 0.981%,respectively.However,the contents of flavonoids in the root,stem and leaf were 0.032%,1.212% and 2.259%,respectively.The phytochemical result was consistent with that of histochemistry.Research showed that,the accumulation of saponin in the root occupied first place and it had scientific gist that the main medical part was the dry root of B.scorzonerifolium Willd.in “Chinese Pharmacopoeia”.Meanwhile,the content of flavonoids in the leaf was considerably high,thus to exploit the flavonoids in B.scorzonerifolium Willd.,its leaves should be mainly collected.

Abstract:The structures of different organs of Camptotheca acuminata Decne.were studied using anatomical methods and the dynamic changes of CPT contents of different organs were identified by HPLC.The result indicated that:(1)The structure of root longitudinal section of C.acuminata is the same as other dicotyledons,namely,it is composed of root cap,meristematic zone,elongation zone and maturation zone.The primary structures of root and stem are composed of epidermis,cortex and vascular cylinder.Osmiophilic cells are showed in cortexs and piths.In secondary growth,the cork cambium of root derives from pericycle,while the cork cambium of stem derives from cortex.With the secondary growth,the center of stem becomes hollow.The cross section of blade is composed of epidermis,mesophyll and vein,and osmiophilic cells are also found in the mesophyll.With scanning electron microscope and optics microscope observing,stomatal apparatus are only absent in adaxial epidermis of leaf and abnormity.The guard cells are nephroid,and subsidiary cells have not been observed.The leaf surface has three types of trichomes,one type is unicellular non-glandular which is distributed in the adaxial and abaxial epidermis of leaf.Other types are glandular hairs,in which one is global distributed in both adaxial and abaxial epidermis and the other is olivary distributed only in the abaxial epidermis.It was found that the younger the leaf is,the more the trichomes are distributed.(3)The HLPC results showed CPT contents in young leaf and seed is higher than that in xylem,the lowest in piths.CPT content of leaf gradually decreased with the leaf becoming mature.The content has differences between different parts in the same leaf.CPT contents have changed in the development of C.acuminata seedling.

Abstract:We conducted an anatomical study on the formation of adventitious roots of Tetraena mongolica stem cuttings by paraffin section method to investigate the rooting type,rooting position,and the relationship between rooting and callus generation,and the formation of adventitious roots.The results showed that:（1）T.mongolica has typical stem structure of woody plants and sclerenchyma was not found in the stem cortex.（2）Stem parenchyma tissues contained abundant starch grains and proteins.（3）There were no latent root primordia in stem cuttings.Root primordia were formed by the dedifferentiation of callus parenchyma cells and finally developed into adventitious roots.These anatomical observations indicate that callus is a prerequisite for the formation of adventitious roots and T.mongolica rooting belongs to callus rooting-type.

Abstract:Jasmonate,act as insect herbivore and wounding related plant hormone,play pivotal roles in plant defense and development.However,the mechanism of plant defense induced by MeJA remains unclear.Our studies preliminary reveals the regulation relationship between PM H⁺-ATPase and H₂O₂ accumulation.We showed that:MeJA activated the PM H⁺-ATPase firstly,which resulted the H⁺ efflux out of cell and cytosolic alkalinization.Further,the increase of cytosolic pH activated the NADPH oxidase,which promoted the accumulation of H₂O₂.These results suggested that the accumulation of H₂O₂ were regulated by PM H⁺-ATPase,which would benefit plants for defending against insect attack and pathogen infection.

Abstract:The core components of abscisic acid (ABA) signal transduction in plants include ABA receptors (PYR/PYL/RCARs),group A type 2C protein phosphatases (PP2Cs) and SNF1-related protein kinases 2 (SnRK2s).In this study,via BLASTP,14 PtPYR,7 PtPP2C and 4 PtSnRK2 genes were obtained in Populus trichocarpa.They are homologous to Arabidopsis AtPYR,AtPP2C and AtSnRK2 genes,respectively.Based on phylogenetic analysis,PtPYRL7,PtPYRL9,PtHAB2,PtPP2CA,PtSnRK2.3 and PtSnRK2.6 were chosen and their primers were designed.Total RNA in Number 85 clonal Populus tomentosa leaves were isolated after 3 hour,6 hour,12 hour and 24 hour exogenous ABA treatment and chito-oligosaccharide treatment of its roots.Real-Time quantitative PCR results have shown that:(1)The expression levels of PtPYRL7 and PtPYRL9 were down-regulated after ABA or chito-oligosaccharide treatment;(2)The expression levels of PtHAB2 and PtPP2CA were up-regulated after ABA or chito-oligosaccharide treatment;(3)The expression levels of PtSnRK2.3 and PtSnRK2.6 were up-regulated first and then down-regulated after ABA or chito-oligosaccharide treatment.The study indicated that ABA signaling pathway was one of signal transduction ways of chito-oligosaccharide induced disease resistance in Populus tomentosa.

Abstract:To explore the effect of chilling stress on antioxidant activities in the leaves of chilling tolerance ruble tree ‘Zhanshi 327-13’ and chilling sensitive variety ‘Wenchang 217’,we treated the seedlings of both varieties by chilling stress at 8 ℃/8 (day/night).Antioxidant activities and the related physiological parameters were determined every day from the beginning of treatment.Then,the content of H₂O₂ in guard cells was measured by laser confocal microscope in different time after chilling stress.The results showed that:(1)The released rate of superoxide radical anion and the activities of superoxide dismutase (SOD),catalase (CAT),peroxidase (POD) and APX in the leaves of ‘Zhanshi 327-13’ and ‘Wenchang 217’ increased first and then decreased under chilling stress;And the activities of anti-oxidases in the leaves of ‘Zhanshi 327-13’ were constantly higher than those in ‘Wenchang 217’ during the whole experiment;The content of H₂O₂ maximized at the first day in the leaves of ‘Zhanshi 327-13’ but maximized at the third day for ‘Wenchang 217’ after chilling stress.(2)The content of H₂O₂ in the leaves was consistent with that in the guard cells.Our experimental results suggested that the quick accumulation of O^-·₂ and H₂O₂ in ‘Zhanshi 327-13’ probably played a role in molecular signaling pathways through which increased the antioxidant activities,decreased oxidant stress and kept lower content of TBARS.Lower relative conductivity was maintained after chilling stress in the leaves of ‘Zhanshi 327-13’ so as to increase the tolerance to chilling.

Abstract:In this study,two individuals,GS-Y14 with high acid content and DS-Y182 with low acid content,from hybrid offspring of ‘Yali’בJingbaili’ were used to analyze the dynamic changes of organic acid and enzyme activities in pear fruit.The results showed that GS-Y14 belongs to malic acid dominant type,DS-Y182 belongs to the citric acid dominant type.The difference in total acid contents between DS-Y182 and GS-Y14 individual was mainly attributed to the content of malic acid during ripening.NADP-ME as key enzyme plays a decomposition role in malic acid pathway,and showed significant difference near ripening in two species,so the NADP-ME was the main reason leading to the difference of malic acid between GS-Y14 and DS-Y182,and effect the final acid accumulation in fruit during ripening.The increasing activity of PEPC favored the synthesis of citric acid.CS is the key enzyme in the change of malic acid content.In the early period,Cyt-ACO and Mit-ACO showed little effects on the change of citric acid content.In the later period,the activity of NAD-IDH enzyme has a certain effect on the citric acid accumulation in different progeny.

Abstract:In order to clarify the changes of main non-volatile organic acid concentrations and metabolism related enzymatic activities in the process of the growth of flue-cured tobacco leaves,we used 12 flue-cured tobacco varieties to study the dynamic changes of total organic acid content,malic acid content,citric acid content,metabolism related enzymatic activities,the nicotine content and sensory quality of modulated smoke sample.The results showed that:(1)With the growth of tobacco plants,flue-cured tobacco total organic acid content indicated a trend of first increased and then decreased,in the middle of leaf age 50～60 d reached the highest value.The total organic acid content of different flue-cured tobacco variety middle leaves had significant differences in different age periods,while had little changes before and after modulation.(2)Malic acid content had a trend of gradually growth.Citric acid content displayed a slow “increase-decrease” trend.Malic acid content and the NAD-MDH(malic dehydrogenase) activity had a significant negative correlation.Citric acid content and the CS(citrate synthase) activity had a significant positive correlation,while had little correlation with the NAD-IDH(isocitrate dehydrogenase) activity.(3)When the total organic acid content was more than 32%,nicotine content was between 1.5% and 2.6% at the same time,the higher “acid-base ratio”,the better sensory quality of flue-cured tobacco.In summary,the accumulation of malic acid and citric acid in flue-cured tobacco leaf were regulated by the changes of its metabolism related enzymatic activities.“Acid-base ratio” influenced the smoke mildness of flue-cured tobacco.Through regulating NAD-MDH and CS activities to adjust the contents of malic acid and citric acid,coordinating “acid-base ratio” and improving the quality of tobacco.

Abstract:The effects of nitrate (NO₃^-) stress with 0,50,100,150,200 mmol·L^-1 concentrations were studied on growth and physiological and biochemical indexes of cherry tomato (Lycopersicon esculentum Mill.var.cerasiforme Alef.) variety ‘Dahong cherry tomato’ using the hydroponic culture test.The results showed that the plant height,fresh weight,dry weight and relative water content decreased with the increasing of nitrate concentration after treated for 6 days,while the root to shoot ratio increased first and then decreased.The contents of TBARS,ROS,H₂O₂ and protein carbonyl (PC) of tomato seedlings increased with the increasing of nitrate concentration.The activities and gene expression of SOD,POD,CAT and APX of tomato seedlings decreased with the increasing of nitrate concentration.The contents of proline,soluble sugar and soluble protein of tomato seedlings increased with the increasing of nitrate concentration.Our experiment indicated that the 50 mmol·L^-1 NO₃^- had little effect on the plants,while 100 mmol·L^-1 NO₃^- inhibited the growth of tomato seedlings,caused damage to the membrane lipid and decreased the activities of antioxidant enzymes (SOD,POD,CAT and APX);However,the increased osmotic adjustment substance could adjust themselves to avoid nitrate stress,which led to some tolerant ability of tomato to nitrate stress.

Abstract:The effects of medium components and culture conditions on pollen germination and pollen tube growth of Calanthe tsoongiana T.Tang et F.T.Wang in Tianmu Mountain were studied by in vitro culture,which was also used to investigate the pollen storage capacity.The stigma receptivity was estimated by benzidine-H₂O₂ method.The aim of present study was to screen the ideal culture methods and storage conditions for C.tsoongiana pollens,which would lay the foundation for the research of its germplasm resources preservation.The results showed that:(1)The optimum culture medium for pollen germination consisted of 200 g·L^-1 sucrose,50 mg·L^-1 H₃BO₃ and 40 mg·L^-1 Ca(NO₃)₂·4H₂O,in which the pollen germination percentage was nearly 81.71% and the average pollen tube length reached 247.42 μm after 48 h incubation under the optimum culture conditions involved pH 5.5～6.0 and 25 ℃.(2)Germination rate of dried pollens still maintained at 48.58% after 360 d storage under -80 ℃.(3)The stigma receptivity of C.tsoongiana could last 5 d after blooming,but the pollinarium kept a certain viability (28.96%~81.71% germination rate) during whole florescence.However,both stigma receptivity and pollen viability declined significantly with the extension of time after blooming.

Abstract:The effects of different seasonal grazing (i.e.summer grazing or winter grazing) on plant composition and diversity in Kobresia humilis alpine meadow were investigated from 2007 to 2011 on the Tibetan plateau using the quadrat method.This study shows that:(1) After long-term different seasonal grazing,the proportion of gramineous functional group reduced and the proportion of the forb functional group increased under both summer grazing and winter grazing;(2)Grazing in different seasons had significant influence on the proportion of different species in the plant community.Compared with no grazing,summer grazing increased the proportion of K.humilis,Taraxacum mongolicum and Potentilla anserina in the community 151.38%,318.87% and 344.15%,respectively,but decreased the proportion of Stipa aliena 41.16%;winter grazing increased the proportion of P.anserina 124.08%,but decreased the proportion of Poa pratensis 45.99%.However,they had no significant influence on the proportion of,Scirpus distigmaticus,Festuca rubra,Elymus nutans,Trigonella ruthenica and Thalictrum alpinum.(3)Generally,the influences of grazing in different seasons on the species richness,diversity index and evenness index of plant communities were not significant but varied with the year.

Abstract:In order to find out species composition and interspecific relationship of reed community in Dunhuang Westlake Wetland of Gansu,we investigated the relevance and correlation of 28 sepcies pairs (between species to species) composed of 8 dominant species of reed community in Dunhuang Westlake Wetland of Gansu,according to quadrat investigation of plant community,on the basis of 2×2 contingency table,using analysis of variance,chi-square test,Ochiai index,Dice and Jaccard index.The results showed:(1)The overall correlation among dominant species of reed community showed a significant positive correlation;(2)Among the 28 sepcies pairs,20 pairs showed a positive correlation accounted for 71.4% of the total correlation pairs;8 pairs showed a significant negative correlation accounted for 28.6% of the total correlation pairs;(3)Reed community species pairs showed a significant positive correlation,and the logarithmic ratio of positive and negative correlation was 2.5.The positive correlation was dominated (correlation was weak) and the negative correlation was low (correlation was strong).The correlation and probability of common occurrence of 28 species were not high,and most showed no correlation.

Abstract:Due to the special role as connection corridor between oasis and desert,oasis-desert ecotone was a key area to carry out research on ecosystem degradation and recovery in arid region.As the result of dry climate,fragile environment system and long-term human activities,Minqin oasis and its surrounding areas had degraded seriously.In this study,the desert plant communities in the oasis-desert ecotone of Minqin (Minqin ODE) were selected as case study.We obtained valuable data on 19 major plant species from 47 study plots of desert plant communities in Minqin ODE and analyzed that by the means of two-way indicator species analysis (TWINSPAN) and detrended correspondence analysis (DCA) in order to identify the main plant associations and environment gradient correlated to their distribution.The results show that:(1)In Minqin ODE,the structure of desert vegetation communities is simple and the species of plants have the characteristics of drought resistance and salt tolerance (2)The outcome of TWINSAN shows that the desert plant communities in Minqin ODE were composed of 11 plant associations and its rationality was verified by DCA ordination.Meanwhile,the succession trends of Minqin ODE are also reflected spatially in the classification result.The main associations include Nitraria tangutorum+Halogeton glomeratus,N.tangutorum+Phragmites australis,N.tangutorum+Kalidium foliatum,K.foliatum+Lycium ruthenicum et al.(3)The result of DCA ordination shows that the groundwater table and landforms are the leading factors which decide the association type and spatial distribution of desert plant communities in the Minqin ODE.

Abstract:In order to exploring litter yield and dynamic changes of monsoon evergreen broad-leaved forest,we set collecting nets to gather litter at regular intervals in different restoration stages and analyzed litter yield.The results showed that:(1)The annual litter yield was between 8 133.1 and 8 798.3 kg/hm² in different restoration stages of the communities,and the annual litter yield from high to low is 30a communityCastanopsis echidnocarpa,Castanopsis hystrix,and Schima wallichii,the highest annual leaf litter was the C.echidnocarpa for all communities (53.93% for 30a community,47.83% for 40a community and 28.32% in old growth forest),the second was S.wallichii (8.45% for 30a community,10.71% for 40a community and 31.69% for old growth forest),the lowest was the C.hystrix (6.1% for 30a community,7.53% for 40a community and 6.36% for old growth forest).The leaf litter dynamic change of C.echidnocarpa was unimodal curve for restoration communities,but it was polymodal curve for old growth forest;the form of leaf litter of S.wallichii was unimodal curve for all communities;the leaf litter dynamic change of C.hystrix was unimodal curve for 30a community and old growth forest,but it was polymodal curve for 40a community.

Abstract:Based on detailed field investigation,collection of specimens and identification of Amblystegiaceae,Brachytheciaceae and Hypnaceae in Xinjiang,we reported 114 species belonging to 38 genera.Among them,33 species of 15 genera belong to Amblystegiaceae,51 species 12 genera to Brachytheciaceae and 30 species of 11 genera to Hypnaceae.There are 4 genera and 37 species new to Xinjiang,among which 2 species reported new to China.The moss flora of Amblystegiaceae,Brachytheciaceae and Hypnaceae of Xinjiang was divided into 9 areal-types.The total elements were dominated by North Temperate representing 52.08% of the total species,followed by East Asia element,and the tropical element is little.According to comparisons of Xinjiang and 7 neighborhoods(Tibet,Inner Mongolia,Russia,Mongolia,Kazakhstan,Pakistan and India),India has the highest species richness index,followed by Russia and Xinjiang.The values of similarity coefficient of flora between Xinjiang and Inner Mongolia and Russia are higher than that of other regions.Cluster analysis of these 8 regions showed that Xinjiang has the closest relatives of flora with Inner Mongolia,and the moss flora of Xinjiang is closely associated with Russia.

Abstract:To elucidate the formation and inheritance of flower fragrance of Lagerstroemia and the volatile components of flower scent,we chose L.caudata(W₁),L.indica ‘Duohuafen’(C),and their hybrid of different generations,including F₁ hybrid between L.caudata×L.indica ‘Duohuafen’ (F₁),F₁ backcrossed with L.caudata (BC₁) and F₁ selfing (F₂) to investigate the flower aroma components by using headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC/MS).The results showed that:(1)25,10,25,26 and 26 volatile compounds were identified from the flowers of W₁,C,F₁,F₂ and BC₁,respectively.(2)Myrcene was the only mutual ingredient among L.caudata and its hybrids,of which the relative contents were not high [0.69% (W₁),3.16% (F₁),0.51% (F₂) and 0.75% (BC₁),respectively].(3)Main aroma ingredients and their relative contents were quite different among the parents (W₁ and C) and their hybrids (F₁,F₂ and BC₁):iso-Geraniol (26.21%),1,1-Dimethyl-3-methylene-2-vinylcyclohexane (50.34%),1,3,6,10-Dodecatetraene,3,7,11-trimethyl-,(3E,6E)-(11.37%),Cyclohexene,2-ethenyl-1,3,3-trimethyl-(14.67%) and trans-α-Bergamotene (16.19%),respectively.(4)The main aroma components of L.caudata,L.indica ‘Duohuafen’ and F₁ were fatty acid derivatives from lipoxygenase pathway,whereas terpenoids from the mevalonate (MVA) pathway and 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway were the main aroma components of F₂ and BC₁.

Abstract:Impatiens kerriae Craib is reported as a new record species to China.It has been previousy known from Thailand.The detailed description of this species is given here,flowering and fruiting time are described for the first time.The voucher specimens are kept in Herbarium of Xishuangbanna Tropical Botanical Garden.

Abstract:Four newly recorded species of vascular plants in Inner Mongolia are reported.They are Tamarix arceuthoides Bunge,Cuscuta campestris Yuncker,Juncus libanoticus Thiébaut and Stellaria pallida (Dumortier) Crépin.Two new synonyms,Borodiniopsis D.A.German (Oct.2012) and Borodiniopsis alashanica (Maxim.) D.A.German et al.(Oct.2012) in the family Cruciferae are proposed,which should be rejected and replaced by Acirostrum Y.Z.Zhao (Aug.2012) and Acirostrum alaschanicum (Maxim.) Y.Z.Zhao (Aug.2012)，respectively.

Abstract:The genus Melodinus J.R.et G.Forst.(Apocynaceae) and the species Melodinus fusiformis Champ.ex Benth.,the genus Phaius Lour.(Orchidaceae)and the species Phaius flvus (Bl.) Lindl.,the genus Diplacrum R.Br.(Cyperaceae) and the species Diplacrum caricinum R.Br.,collected from Ganzhou City,were reported as new records in Jiangxi Province,China.Being all the tropical floristic elements,they are as further evidence information to support the claim that in the south of latitude 25°40′N South Jiangxi belongs to South China floristic region.All of the voucher specimen are deposited in Dendrological Herbarium of Forestry College,South China Agricultural University (CANT).

Abstract:A preliminarily study on the xerophytic mosses Aloina Kindb.and Pterygoneurum Jur.of the family Pottiaceae in Hebei Province,China was reported.The genus Pterygoneurum and two species,namely Pterygoneurum subsessile (Brid.) Jur.and Aloina cornifolia Delgad.,were newly recorded in Hebei Province.The general data on the diagnostic characters,habitats,and geographic distribution of each species were discussed and the illustrations were provided.The key to the species of Aloina in Hebei Province was also compiled.

Abstract:In type specimens deposited at China National Herbarium (PE),Institute of Botany,the Chinese Academy of Sciences,the types of eighteen names,Carex ischnostachya Steud.var.subtumida Kük.(Cyperaceae),Carex poculisquama Kük.(Cyperaceae),Scirpus pumilus Vahl subsp.distigmaticus Kük.(Cyperaceae),Aspidistra caespitosa C.Pei (Liliaceae),Campylandra longibracteata F.T.Wang & T.Tang (Liliaceae),Chionographis chinensis K.Krause (Liliaceae),Lilium sutchuenense Franch.(Liliaceae),Lloydia oxycarpa Franch.(Liliaceae),Lloydia tibetica Baker var.lutescens Franch.(Liliaceae),Lloydia yunnanensis Franch.(Liliaceae),Nomocharis henricii E.H.Wilson.f.maculate W.E.Evans (Liliaceae),Ypsilandra yunnanensis W.W.Smith (Liliaceae),Dioscorea esquirolii Prain & Burkill (Dioscoreaceae),Dioscorea platanifolia Prain & Burkill (Dioscoreaceae),Iris bungei Maxim.(Iridaceae),Iris polysticta Diels (Iridaceae),Liparis cucullata S.S.Chien (Orchidaceae) and Orchis diantha Schltr.(Orchidaceae),of taxa in Monocotyledon are found to be syntypes under Article 9.5 of the International Code of Nomenclature for Algae,Fungi,and Plants (Melbourne Code).According to Article 8.1,9.11 and 9.12,and Recommendation 9A.2 and 9A.3,lectotypes for these eighteen names are here designated.

Abstract:The methanol,which is one of the simplest organic C₁ compounds produced during the plant growth,development and metabolisms,is related to many plant physiological processes (such as photosynthesis,biological synthesis of C₁-tetrahydrofolate and some phytohormones,and stress tolerance).In this paper,the pathways for methanol production and emission,metabolisms,and the role of exogenous applying methanol on plants and its physiological mechanisms are summarized according to the existing references,and on that basis,the present occurred problems and future research focus are also discussed.

Abstract:Rubus is a large and taxonomically complex genus consisting of hybrid and polyploid.In this review,we summarized and discussed the application of DNA sequences in the Rubus L.phylogenetic studies,mainly focus on their limitation and promising application prospect in the Chinese Rubus.Noncoding chloroplast DNA fragments combined with ITS sequence were frequently applied.ITS was the most widely applied sequence among the nDNAs.It has been used for clarifying the phylogeny between sections Idaeobatus and Malachobatus,illustrating genetic relationship among Rubus cultivars,and identifying the origin of hybrid and polyploid.Due to ITS polymorphism among individuals,it was necessary to detect putative pseudogenes.By contrast,low-copy nuclear genes were rarely applied except GBSSI and LEAFY.The phylogenetic relationships of some Rubus species remain unclear because of the deficiency of available DNA sequence and limitation of covered groups.Additionally,utilization of multi-specific DNA and more samples in phylogenetic applications probably has one bright future,along with the morphology,palynology,cytology and other means.