Abstract:In this study,the wild banana in Fuzhou with stronger anti-cold ability was used as materials to clone the iron superoxide dismutase family (FeSOD) genes.Two FeSOD genes with four transcripts,designed as MuFSD1A(Accession No.JX844026),MuFSD1B(Accession No.KJ786318),MuFSD1B-variant1(Accession No.KJ786319) and MuFSD1B-variant2(Accession No.KJ786320),respectively,were obtained by RACE and RT-PCR.The full-length cDNA sequences of MuFSD1A were 1 277 bp,encoding a 300 aa polypeptide,while that of the MuFSD1B were 1 378 bp,encoding 260 amino acids.Genomic structure analysis revealed that MuFSD1B-variant1 and MuFSD1B-variant2 were alternatively spliced variants of MuFSD1B.Bioinformatics and subcelluar localization analyses indicated that both MuFSD1A and MuFSD1B were mainly located in chloroplast,but their physicochemical properties,phosphorylation sites and protein structures were different from each other.Sequence alignments showed that MuFSD1A and MuFSD1B shared a low sequence identity (33.33%),although they all carried the conserved metal ligand binding sites and residues essential for distinguishing FeSOD from MnSOD.Phylogenetic analysis suggested MuFSD1A and MuFSD1B are grouped into different clusters.qRT-PCR results revealed that cold stress induced the expression of MuFSD1A but suppressed MuFSD1B expression.In addition,the expression level of MuFSD1A was significantly enhanced with the temperature decreasing,indicating this gene member might play a major role in banana cold resistance.

Abstract:For preliminary study the function of vacuole H⁺-ATPase subunit c gene (VHA-c1) in plant growth and signal transduction,we constructed an over-expression vector of VHA-c1 in Arabidopsis thaliana and introduced it into wild-type A.thaliana.The expression levels of VHA-c1 were analyzed by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR),then the VHA-c1 transgenic homozygotes were treated by dark condition,ABA or sugar.The results showed that:(1)7 lines of VHA-c1 tansgenic homozygotes were obtained,the corresponding transcript level of them increased,indicating that the overexpression constructs are effective.(2)When grown under dark condition,the root length in 6 VHA-c1 tansgenic homozygotes lines were reduced.(3)With treatment by ABA,4 lines reduced the sensitivity in taproot growth and the extent of cotyledon unfolding;7 lines reduced the sensitivity in seed germination.(4)5 lines and 4 lines also reduced the sensitivity to inhibition on seed germination by glucose and sucrose,respective.This indicates that the vacuolar VHA-c1 might be involved in the signalling pathway mediated by ABA and sugar,and possible effect on cell expension.

Abstract:To explore a positive action of the antioxidant defense system in rice plant response to abiotic stress,we used the Affymetrix Rice GeneChip to deduce the expression profiling of rice ROS scavenging system related genes under salt-stress or low temperature-stress treatment.The results showed that:(1)rice ROS Scavenging System involves 187 genes and /or ESTs that were composed of antioxidants,such as ascorbate,glutathione,tocopherols (Vitamin E),and antioxidant enzymes,such as superoxide dismutase (SOD),ascorbate peroxidase (APX),catalase (CAT) and so on.(2)In comparison with the control,there were 5 up-regulation genes (fold change≥2.0,P<0.05,the same as below) and 2 down-regulation genes (fold change≤0.5,P<0.05,the same as below) in Indica cultivar i-93-11 under low temperature stress; otherwise,there were 5 up-regulated genes and 6 down-regulated genes in Japonica cultivar j-NJ-1 under low temperature stress.(3)There were 31 up-regulated genes and 13 down-regulated genes in i-93-11,27 up-regulated genes and 25 down-regulated genes in j-NJ-1 under high salinity.(4)There was a big difference between the expression profiling of ROS scavenging system related genes under salt-stress or low temperature-stress treatment in Indica and Japonica rice.Furthermore,a ROS scavenging network planning in rice responses to high salt and low temperature stress was constructed according to the Affymetrix Rice GeneChip.

Abstract:Dihydroflavonol 4-reductase(DFR) is a key enzyme in the biosynthesis of anthocyanins in tartary buckwheat.The DFR coding gene was amplified from the seed-filling period cDNA of tartary buckwheat by RT-PCR and ligated to the expression vector pET47b.The E.coli BL21(DE3) carrying the DFR coding gene was obtained and induced by IPTG.The expression products were analyzed by SDS-PAGE,purified by affinity chromatograph and the high titer polyclonal antiserum raised against rabbit was obtained.The open reading frame of DFR coding gene was obtained by RT-PCR.As analyzed by PCR and DNA sequencing.The recombinant prokaryotic expression vector was constructed successfully.As analyzed by SDS-PAGE,the DFR had been high-efficiency expressed in E.coli in the form of soluble protein and inclusion bodies.Pure fusion protein was obtained by affinity chromatography.Western blotting analysis showed the raised antibody could specifically react with the antigen and native DFR existed in total protein of seed filling period of buckwheat.These results will be valuable for the further study on the biological function of DFR.

Abstract:Different stages of somatic embryos were obtained in embryogenic callus from embryogenic cell suspension culture of longan,and used these somatic embryos as the test material.The RT-PCR combined with RACE method was used to clone the complete cDNA sequences and DNA sequences of homeodomain transcription factor WUSCHEL(DlWUS) from embryogenic callus of Dimocarpus longan Lour..The complete cDNA sequence of DlWUS was 1 110 bp,encoding 285 amino acids DNA sequence analysis indicated that it contains 2 introns.DlWUS located in nucleus;it had no signal peptide,had transmembrane structure,homeobox domain,WUS box and EAR-like domain.Anglicizing phylogenetic tree of WUS in plants indicated that DlWUS and CsWUS belonged to the same branch,therefore,DlWUS belonged to WUS family.Real-time quantitative PCR results indicated that DlWUS had expression at all stages,but it expressed at the highest levels in the globular embryos,suggesting that DlWUS play a major role at longan somatic embryogenesis.In a certain concentration range,DlWUS showed up-regulated expression patterns under exogenous IAA and GA₃ and down-regulated expression patterns under exogenous SA.

Abstract:Brassica napus cytoplasmic male sterility (CMS) NRO4270A was obtained in the progenies of distant hybridization of Raphanus brassica (RRCC) and B.napus (AACC).(1)The fertility investigations of five consecutive years in both winter and spring rapeseed production areas showed that NRO4270A could not produce pollens completely and its male sterility was extremely stable,which could not be affected by environmental conditions,such as temperature and photo period.Its sterility rate and sterility degree are both 100%.(2)NRO4270A,pol,ogu,kos,hau CMS lines were test-crossing with the restorer lines of pol,ogu as well as cultivar Huashuang 4.It was suggested that NRO4270A had different restorer and maintainer relationship with pol,ogu and kos.(3)Microscopic structure analysis and comparison of anther developments of NRO4270A and its maintainer line NRO4270B indicated that NRO4270A pollen abortions occurred between the tetrad stage and the mononucleate stage.At mononucleate stage,its microspore exine could not form,and its tapetum was vacuolated and expanded.Eventually,its tapetum and microspore were completely degraded.The pollen sacs became empty and the pollens could not be produced in it.(4)The mitochondrial DNAs of NRO4270A,pol,ogu,kos,hau,NRO4270B and Huashuang 5 were analyzed through RFLP by 18 probe/enzyme combinations (six mitochondrial gene,atp1,atp6,atp9,orf222,cox2 and cob,as well as three restriction enzymes,EcoRⅠ,BamHⅠ and HindⅢ),respectively.In 11 combinations,NRO4270A showed significantly different bands with the other materials,suggesting that NRO4270A was a new CMS type.Its discovery and utilization will overcome the problems of environmental sensitivity of Chinese major CMS system and the singleness of sterile cytoplasm type in rapeseed hybrid seed production.

Abstract:In this study,the wide type seeds of Isatis indigotica were used as research materials,and carbon ions (irradiation doses:30Gy,60Gy,90Gy and 120Gy) were used to irradiate the seeds.The impact of different irradiation dosages on seed germination,seeding growth,main effective ingredients,genome and total protein polymorphism of I.indigotica were also comprehensively evaluated,which can provide a reference for I.indigotica breeding,molecular biology researching and the application of heavy ion irradiation mutagenesis.The results showed that:(1)the seedling surviving rate and root fresh weight of I.indigotica gradually decreased with enhanced irradiation intensity.Compared to other dosages,30Gy exhibited the minimum inhibition of growth and maximum increase of main effective ingredients 4(3H) quinoxalinol and indirubin in roots,by 2.2 and 2.3 fold compared to wide type,respectively.(2)SRAP analysis results indicated that the degree of genome variation was increased with enhanced irradiation intensity.Compared to wide type,mutants after using 30Gy had recovered 33.59% polymorphic variations for DNA.(3)SDS-PAGE gels stained by CBB and Pro-Q showed that total protein and phosphoprotein had been changed,but they were not positively correlated with the irradiation intensity,which indicates that plants may have a compensatory mechanism for the damage caused by heavy ion irradiation.After all,for I.indigotica mutagenesis,30Gy is the best carbon ion irradiation dosage which can induce a high content of active ingredients,and these results also laid a basis for mutation breeding of high quality I.indigotica.

Abstract:The genetic diversity of 35 germplasm resources of yam from different places and areas were analyzed by ISSR molecular marker and the primary core collection was constructed by Least Distance Stepwise Sampling.The results showed that:(1)12 primers selected from 32 random ISSR primers which amplified 142 loci including 97.18% polymorphic loci.The average of Shannon information index (I),Nei’s genetic diversity (h),effective number of alleles (N_e) and number of alleles (N_a) by POPGENE 32 analysis was 0.423 0,0.269 4,1.427 1 and 1.971 8 respectively which indicated there was highly genetic diversity in these 35 yam resources.(2)The clustering result of analysis by NTsys2.10e software showed that the genetic similarity coefficient ranged 0.54-0.97.Some materials distributed in different origins and far geographic distance showed high genetic similarity coefficient in 35 accessions.(3)The percentage of polymorphic loci was reduced although the change of Shannon’s information index and Nei’s genetic diversity was not clear with the samples reduced in six samplings.The bank of core collection from No.4 sampling was most representative in six samplings whose sampling number was 31% of the initial sampling and the percentage of polymorphic loci was 97.8% before sampling.

Abstract:By artificial culture,with semithin section and ultrathin section,we continuously observed the whole procedure of sexual reproduction of Isoetes sinensis Palmer.The results showed:(1)both female and male gametophytes are intramural development,there are rhizoids and archegoniums on femal gametophyte;but no rhizoids for male gametophyte,and every male gametophyte have 4 spermatids,all of them have 8-12 flagellums.(2)There are only two neck canal cells and one egg in the archegonium,and the ventral wall cells were transformed from the gametophyte vegetative cells.(3)Between the first division of the zygote and the achegonium’s long axis,there is an angle about 20°,and the embryo with 2-4 cells is easy to division and be aging,organization differentiation obvious on the embryo after 10 cells.(4)When is the globular embryo’s time,the first leaf has not differentiation and ligule primitive cell appeared in the embryo.The first leaf ligule will not development until the first leaf’s upside change to green and get photosynthetic capacity.The results supported the view of the priority development of root and leaf,and we think the main reasons of the I.sinensis endangered are about the male gametophyte’s lower germination rate and the female gametophyte exist more abortive structures.

Abstract:In the perspective of asexual reproduction,the development process of critically endangered level (CR) Isoetes sinensis plant sporangium was continuously observed with method of semithin-section to provide intuitive and reliable theoretical basis for investigating the reasons for its endangered.The result showed that:(1)Megasporophyll and microsporophyll of I.sinensis are alternate arranged,no mixed sporangium.(2)Supplying the nutrients for the spores by septum filament.The size of paraphysis is critical to the size,productivity and fertility of spores.(3)The microsporangia are uniformly developed,while the megasporangia are nonuniformly;both kinds of sporangia present almost 50% abortion.(4)Both kinds of sporangia have no sporangiophore and no annulus also.The spore release depends on sporangium decompose.It suggested that the developing characters of sporangium is one of the endangered reason for I.sinensis due to high abortion rate of sporangia,no release structure or highly environment dependence.Comparing with relative species sporangium,it could be found that only Isoetes spores spread borrowing outside force and the higher requirement on the habitat,which verified the status of Isoetes old system and illustrated the Isoetes has more abilities of monitoring environmental indicators in habitat area.

Abstract:The fertilization of the fern Pteridium aquilinum var.latiusculum are observed using electronic microscopy.(1)The spermatozoid penetrates the egg through the fertilization pore.The gyratory motion of the spermatozoid serves to form a fertilization cavity just beneath the fertilization pore and then enters the egg cytoplasm.(2)The prolonged gyratory motion of the first spermatozoid and irritability reaction caused by the sperm penetration may contribute to block the polyspermy.(3)The nuclear evaginations persist 12 h and then detached from the nuclear body and finally are digested in the zygote cytoplasm.(4)The zygote establishes a horizontal polarity by vacuolization of the cytoplasm in the posterior part of the zygote before the zygote divides.The present study provides some new insights into the cytological mechanism of fertilization in ferns,which contribute to understand the cytological mechanism of the fertilization and evolution of the sexual reproduction of the ferns.

Abstract:Using conventional paraffin section technique,we studied anther wall formation,sporogenesis and gametogenesis in Zephyranthes candida.The main results are as follows:(1) Anthers are tetrasporangiate.Anther wall comprises epidermis,endothecium,one middle layer and tapetum and the development of anther wall is of the Monocotyledonous type.The tapetum belongs to the secretory tape.The endothecium and epidermis persist,but the cells in endothecium develop and become elongated and fibrously thickened.The cytokinesis in the microsporocyte meiosis is successive.Most of the microspore tetrads are tetrahedral and there are a few other types,such as Bisymmetric.Mature pollen grains are 2-celled.(2)The gynoecium is tricarpellary and syncarpous.The ovary is inferior with axile placentation and trilocular with two rows of anatropous ovules in each locule.The ovule is bitegmic and crassinucellate.The embryo sac development follows the Polygonum type.(3)The embryological characters of Zephyranthes are quite different from those of Amaryllidaceae.For example,the development of anther wall is of the Monocotyledonous type in Zephyranthes but of the Dicotyledonous type in Amaryllidaceae.However,these characters of Zephyranthes are similar to those of Liliaceae.

Abstract:Sinosenecio jishouensis D.G.Zhang,Y.Liu & Q.E.Yang is a Critically Endangered (CR) species which is only distributed in Wuling Mountain areas.The breeding system of S.jishouensis was researched by observing floral morphology and dynamic,testing pollen viability and stigma receptivity,and bagging experiments.Clonal architecture was studied by field investigation and laboratory analysis:architectural form of rhizomes,configuration characteristics of rhizomes,and branching angle between rhizomes.The result shows that:(1)the flowering period of the S.jishouensis population lasted about 45-50 days and with inconspicuous second blooming.The life span of individual plant was usually about 10-22 days.For a single capitulum,it could last 3-5 days.The stigma was obviously higher than the canister when pollen dissemination.As a result,there is a spatial isolation of corolla,anther canister and stigma with in the same floret.(2)The out-crossing index and pollen-ovule ratio of S.jishouensis were 5 and 3 188,respectively.The breeding system is obligate xenogamy,predominant in cross-pollination and fruit setting is depended on pollinators of this species.(3)The ramets and rhizomes per clone of S.jishouensis averaged 3.61 and 4.74,respectively.Branching angle between rhizomes usually was 30°.The architectural form rhizomes of its species belongs to phalanx system for the branch distance of rhizomes is short,and the rhizome rupture is the result of the tissue piecing.Unique adaptive strategy had been formed for adapting to the special habitat.S.jishouensis used clonal reproduction to occupy habitats at first,and then took various measures to enhance cross-pollination rate for producing high-quality of seeds,such as mass-flowering,dichogamy,generating a large number of pollens etc.

Abstract:To breed new Mei cultivars with cold-resistant and blossom early characteristics,we investigated the interspecific compatibility between Prunus mume and P.davidiana by observing fruit set and the pollen tube growth by means of fluorescence microscopy,and immature embryo culture.Results showed that:(1)The fruit set was quite low in all crosses,especially the cross of P.mume ‘Jiangmei’×P.davidiana ‘Alba’failed to form fruits.The cross of P.mume ‘Dan Fenghou’×P.davidiana obtained the highest fruit set 7.4%,and part of fruits were abortive.(2)After cross-pollination,the pollinations of P.davidiana and P.davidiana ‘Alba’ could germinate normally on the stigma of P.mume,but the pollen tube growth was hindered along the style.A higher number of pollen tubes stopped growing when reaching the middle section of the style,and some bended,twined and fractured,but no pollen tubes were observed reaching the base of the style or growing down to the ovary.A large amount of callose accumulated in the process of pollen tube growth which showed the cross-incompatibility.There were differences between cross combinations.(3)Hybrid has been successfully obtained by culturing immature embryo,which indicates that embryo rescue techniques facilitate hybrid creation.

Abstract:The soil cultivation experiment was used to investigate the accumulation and distribution of cobalt in broad bean(Vicia faba L.) and the effects of cobalt on the photosynthetic characteristics and antioxidant properties of broad bean leaves.Broad bean seedlings at the six-leaf stage were treated with different concentration cobalt(0,20,40,80,120 mg·kg^-1),and the cobalt content in roots,stems and leaves,photosynthetic pigment content,photosynthetic gas exchange parameters,chlorophyll fluorescence parameters of leaves,growth indexes,POD,CAT and SOD activities of leaves were investigated on the 14th day after the cobalt treatment.The results showed that:(1)the roots,stems and leaves of broad bean could absorb and accumulate a certain amount of cobalt,and there was a significant positive correlation between the cobalt content of broad bean and soil cobalt content.There were obviously differences in cobalt content between the different organs,and the order of cobalt content from high to low was roots,leaves and stems.(2)Chlorophyll a content(Chl a),chlorophyll b content(Chl b),stomatal conductance(G_s),the maximal photochemical efficiency of PSⅡ(F_v/F_m) and the potential activity of PSⅡ(F_v/F₀) took on the promoting effects on 0-40 mg·kg^-1 and the inhibitory effects on 40-120 mg·kg^-1;Net photosynthetic rate(P_n),intercellular CO₂ concentration(C_i),the minimum fluorescence of PSⅡ(F₀),the maximum fluorescence of PSⅡ(F_m) took on the promoting effects on 0-80 mg·kg^-1 and the inhibitory effects on 80-120 mg·kg^-1;Transpiration rate(T_r),carotenoid content(Car) took on the promoting effects on 0-120 mg·kg^-1,and all photosynthetic parameters in promoting maximum 40 mg·kg^-1.(3)Root length,plant height,biomass,POD,CAT and SOD activities showed a obvious rise under low concentrations of cobalt,and a decline under high concentrations of cobalt.These results showed low concentrations of cobalt could improve the photosynthesis and growth,while high concentrations of cobalt significantly inhibited the photosynthetic efficiency,growth and development of plants.

Abstract:The ornamental plant,Brassica oleracea L.var.acephala DC.was selected to study characteristics of tolerance and accumulation for cadmium (Cd),aiming to explore its feasibility in phytoremediation.The results showed that:(1)the dry weight of B.oleracea L.var.acephala DC.increased at first and then decreased with increased Cd concentrations,20-80 mg·kg^-1 Cd treatment could promote the growth of B.oleracea.Higher Cd concentration at 100-120 mg·kg^-1 inhibited roots growth significantly,while promoted growth of shoots,and there was no distinctive difference in whole plant,showing that B.oleracea L.var.acephala DC.had strong capability in tolerance,and the tolerance in shoots was higher than in roots.(2)B.oleracea L.var.acephala DC.has higher activities of antioxidant enzymes such as SOD,POD,APX and lower contents of MDA and electrolyte leakage in leaves.But when the Cd concentration exceed 80 mg·kg^-1,the activities of antioxidant enzymes such as SOD,CAT and APX in roots were decreased,and MDA contents and electrolyte leakage increased significantly,induced severe membrane lipid peroxidation damage,this may be one of the reason of higher tolerance for Cd in shoots than in roots.(3)Cd contents in shoots was higher than in roots,and Cd content in plants increased gradually with the increase of Cd concentration,and reached the maximum at 120 mg·kg^-1 Cd treatment,and the highest Cd contents in roots,shoots were 50.15 mg·kg^-1 and 52.01 mg·kg^-1,respectively.The translocation factor were above 1,Cd accumulation amount in shoots was higher than in roots,and the highest Cd accumulation amount of shoots was 343.19 μg·plant^-1.These results indicated that B.oleracea L.var.acephala DC.had strong capability in tolerance,accumulation and translocation of Cd,and it is a preferable phytoremediation germplasm resources in ornamental plant for Cd polluted soil.

Abstract:Phalaenopsis ‘Taiwan’s Golden’(seedling age 15 months) were used as the study materials.Its leaves were sprayed with 200 μmol·L^-1 SNP(NO donor),and then plants were treated under 12 ℃/7 ℃(day/night).The electrolyte leakage rate,MDA content,pH,osmotic adjustment substances contents and protective enzymes were determined on five days and ten days after cold treatment.The results showed that the SNP treatment could restrain the increase of pH,electrolyte leakage rate and MDA content effectively,increase the contents of soluble sugar,soluble protein and proline and delay the decrease of SOD,POD,CAT and APX activities significantly,enhance the activities of PPO and PAL.The above results indicated the SNP treatment could reduce the damage under low temperature,improve the ability of resistance to low temperature stress in Phalaenopsis plants through protecting the cell membrane system,increasing the osmotic adjustment substance contents and improving the activities of protective enzymes.

Abstract:In order to study the effects of different concentrations of BR on the chilling resistance of Dendrobium huoshanense,we carried out this experiment with annual stems and leaves of biennial D.huoshanense.D.huoshanense plants were sprayed by 0,0.01,0.05,0.10,0.50 mg·L^-1 BR,respectively,then suffered chilling stress ［day/night temperature were (4±1) ℃/(2±1) ℃,respectively］ for 48 h.The changes of chlorophyll content,autioxidant enzyme activities,MDA content,relative conductivity,proline content in leaves and soluble sugar content in the stems of D.huoshanense seedlings were determined.The results showed that:(1)Under chilling stress,chlorophyll content was decreased constantly.The activity change trends of SOD,POD and CAT all showed unimodal curve and the peaks were all at the 10th day after chilling stress,MDA content and relative conductivity were both increased constantly in leaves.(2)Pretreatment of leaf spraying BR significantly alleviated the hurts of chilling stress on D.huoshanense,significantly improved chlorophyll content,activities of SOD,POD and CAT,significantly reduced MDA content,relative conductivity in leaves and significantly improved proline content in leaves and soluble sugar content in the stems.(3)The effects of the treatment with BR concentration 0.10 mg·L^-1 were significantly better than those of other treatments.So,BR could effectively relieve the peroxide damage to D.huoshanense plant caused by chilling stress,improve its chlorophyll content in leaves,enhance its chilling resistance by improving autioxidant enzyme activities in leaves and their osmotic adjustment ability under chilling stress and BR concentration of 0.10 mg·L^-1 was recommended.

Abstract:Taking Rhododendron hybrides as materials,we investigated the bud soluble sugar,starch,soluble protein and free amino acid and initial time of flowering under nine temperatures and light intensities treatments that were three day/night temperatures(6 ℃/0 ℃,22 ℃/16 ℃,30 ℃/24 ℃) combined with three light intensities(2 000/10 lx,7 500/5 500 lx,10 000/8 000 lx).The results showed that soluble sugar content and starch content increased all the forcing time following rising temperatures and light intensities.The soluble protein content increased in prophase,but decreased in anaphase in the early stage.It increased with the temperature and light intensity increasing,while it was conversely in the later stage.Whereas the change of free amino acid content was opposite to soluble protein.The initial time of flowering of the treatment(30 ℃/24 ℃,10 000/8 000 lx) was the earliest,18 days earlier than target date(Spring Festival).All the those explained appropriate higher temperatures and light intensities (22 ℃/16 ℃-30 ℃/24 ℃,7 500/5 500-10 000/8 000 lx) significantly enhanced accumulations and metabolisms of R.hybrides bud soluble sugar,starch,soluble protein and free amino acid,promoted buds development and blossom,in order to bring produces to market in advance.

Abstract:The article focuses on the enclosed grassland in sub-alpine meadow.We examined the composition of three different communities by the methods of quadrat survey,measured area-based leaf CO₂ assimilation rate(A_area),foliar nitrogen content(N_mass),leaf mass per area(LMA) and photosynthetic nitrogen-use efficiency(PNUE) of three common species Elymus dahuricus,Cirsium setosum and Medicago sativa to study the variation of plant photosynthetic and physiological characteristics in different communities.The results show that:(1)there is obvious composition difference between three sample areas,community composition,particularly leguminous plants can improve nutrient status.However,plant foliar nitrogen content is influenced by dominant interspecific competition;(2)the same species has different height in different communities and the different communities have different vertical light intensity as well,which lead to significant different of light intensity that same species can obtain in different communities;structure including plant height alter light intensity that plants enable harvested significantly;(3)the illuminance and nutrient are variant between communities,though the variation tendencies of A_area,LMA and PNUE are not same to different plants.However,the strong relationship between N_area and A_area is little changed in general,between communities and among species,basically shows a significant positive correlation.Thus it can be seen that the difference in nitrogen and light intensity caused by community composition and structure is an important factor which lead to different photosynthetic physiological characteristics with same species,while different species have different photosynthetic adaptive mechanism to changing environment.

Abstract:By setting up the controlled-experiment with soil water content,we analyzed the root growth and architecture of Populus euphratica seedling to indicate the relationship between the root development and soil water content.The results showed that:(1)drought stress caused the increase of root to shoot ratio to adapt to the arid environment.(2)A certain degree of drought treatment promoted the development of root morphological characteristics and biomass.But excessive drought stress or soil water content may inhibit root growth.Root was most developed under the 15% water content with continuous water treatments.(3)Ration of width to depth of seedling’s root system was less than 1 with both water treatment,the root have a high ability to grow deeper.The ration under intermittent water treatment was significantly less than those under continuous water treatment.There is a significant positive correlation with water content for both water treatments.(4)Topological index of both water treatment was close to 1 and the root branching patterns were herringbone-like,root branching ability was week.The root extension strategy was helpful for the seedling to survive in dry and infertile soil environment.The index was significantly negatively correlated with the water content for both water treatments.(5)A total of 10 parameters of root architecture were analyzed by the principal component analysis.The parameters of total root length,total root surface area,ration of width to depth and topological index could well present the root architecture characteristics of P.euphratica seedling’s root with both water treatments.We concluded that P.euphratica seedling adapt to the arid environment through the establishment of herringbone-like branching patterns,increase of the vertical longitudinal extension ability and root to shoot ratio.Soil water factor played an important role in regulating P.euphratica seedling’s root growth and architecture.The ability to response to soil water content of P.euphratica seedling’s root system may lead to the success to adapt to heterogeneity in soil water.

Abstract:Seeds and one-year seedlings of Casuarina equisetifolia from 20 provenances were studied on weight per thousand seeds and seven characters (height,ground diameter,thickness of first order branches,length of first order branches,length of second order branches,nodes per branch,teeth),in order to investigate the morphology diversity of C.equisetifolia and collect the base genetic information for early genetic selection of this specie.The results showed that:(1)highly significant variance of weight per thousand seeds could be both found between the provenances and the regions(P<0.01),and the variation of weight per thousand seeds has shown significant geographic pattern.The weight per thousand seeds would decreased with the increment of longitude;(2)height and ground diameter have extremely significant different between regions and in region(P<0.01),the provenance from Do Donggang Thailand has the best growth condition,for height is 76.6 cm,ground diameter is 4.64 mm;while provenance from Tonga has the worst seedling growth,for height is 28.3 cm,ground diameter is 2.58 mm;(3)highly significant difference of thickness of first order branches,length of first order branches,length of second order branches,nodes per branch and teeth could be found between regions and in region;of which,the coefficient variation between regions of teeth was maximum (82.15%);(4)path analysis results showed that length of first order branches has a significant effect on height,thickness of first order branches and length of second order branches have significant effect on ground diameter.These three traits could be used as reference factor for excellent variety selection of C.equisetifolia.

Abstract:In order to explore the diversity and variation characteristics of phenotypic characters of wild apricot germplasm resources in Xinjiang.135 individual samples of three wild apricot germplasms populations in Xinjiang were taken as the experiment materials in this paper.And the relevant indicators of the plant morphological characteristics were measured.Phenotypic index and principal component analysis were analysed by DPS7.05 software,and the euclidean distance were calculated,too.The clustering analysis that based on euclidean distance of three populations were analysed by MEGA3.1 software with UPGMA method.The results were showed:(1)simpson and Shannon-weaver index of numerical and non-numerical characteristics of Huocheng population were all the highest (0.979 9,0.979 9;0.981 9,0.981 9),Gongliu population was in the middle(0.975 5,0.975 5;0.978 6,0.978 6),Xinyuan population was the smallest (0.944 7,0.944 7;0.945 2,0.945 2).The phenotypic diversity of Huocheng population was the richest,Gongliu population was in the middle,and the phenotypic diversity of Xinyuan population was the least.(2)The variation coefficient of phenotypic characters of different populations were between 6.16%-54.58%.Most variation coefficients of phenotypic characters were all more than 10%.In Huocheng and Xinyuan populations,the variation coefficient of the shape index was the minimum.But in Gongliu population,the variation coefficient of leaf aspect ratio was the minimum.The variation coefficients of hardness of three populations were all the maximum.Otherwise,the variation coefficients of fruit weight,nuclear fresh weight and shell thickness were generally larger.(3)The genetic distance between Xinyuan population and Gongliu population was the biggest with 20.445 3,the genetic relationship of them was the farthest.The genetic distance between Huocheng population and Xinyuan population was least for 19.218 6,and the genetic relationship of them was close.(4)In the principal component analysis of 35 characters,the cumulative contribution rate of 14 principal components was 80.64%.The leaf length,leaf width,leaf aspect ratio,shape of leaf base,shape of leaf apex,fruit weight,fresh nuclear weight,fresh kernel weight,fruit shape and soluble solids were the main factors that cause the apricot germplasm phenotypic differences.

Abstract:The objective is to compare the different shrub architecture and uncover mechanism of controlled moving sand,also to provide the basic data for simulation research of simulated fixed-sand shrub.The crotch angles,branch length,branch number and architecture of Haloxylon ammodendron,Artemisia ordosica,A.arenaria,Hedisarum scoparium,Calligonum mongolicum,Nitraria tangutorum,Reaumuria kaschgarica were measured and analyzed at the lower reaches of Shiyang River Basin.The results showed that:(1)the mean of crotch angle measured seven shrubs increased gradually from inside to outer position of canopy with four branching ranks.It was only A.ordosica that the length of outer twigs was longer than that of inside twigs of canopy.(2)The number of branching fractal dimension of R.kaschgarica was bigger than that of the other 6 shrubs.Second one of branching fractal dimension was H.ammodendron and N.tangutorum,the least one was C.mongolicum and H.scoparium.The branch-stem ratio was less than one except H.ammodendron.(3)Except C.mongolicum,the number of upwind projected area increased with height of canopy,and gradually decreased at the maximizing point of upwind projected area.R.kaschgarica,N.tangutorum,A.ordosica and H.scoparium were as dense branch shrubs,as sparse branch shrubs of H.ammodendron,C.mongolicum and A.arenaria.

Abstract:Taking Schima superba Cyclobalanopsis glauca mixed plantation (SP) and Elaeocarpus sylvestris pure plantation (EP) both plantations were transformed from degraded shrub forest (DF) in north subtropical areas of China as test objects,we studied the effects of species composition on ecosystem carbon storage of broad leaved plantations.(1)Both the vegetation and soil carbon storage significantly increased after the DF was transformed into broad leaved plantations.The increases of vegetation carbon storage appeared mainly in arborous layers.Compared with DF,the soil carbon storage of SP and EP was significantly increased in each interval of 0-50 cm depth,respectively.(2)The vegetation carbon storage was higher in EP than that in SP,with an increase of 99.4%.Compared with SP,the carbon storage in arborous layer of EP was 27.75 t·hm^-2 higher,which was as twice as that of SP.The soil carbon storage in EP was 10.17 t·hm^-2 higher than that in SP,with a significant difference.In addition,the soil carbon storage in each interval of 0-50 cm depth of EP was higher than that in SP,with significant differences in 0-10 cm and 20-30 cm layer.To sum up,the total carbon storage of degraded shrub forest was significantly increased after transformed into evergreen broad leaved plantation and EP had greater ability of carbon accumulation than SP.Results from the present study suggested that the choice of tree species would be important during the restoration of degraded ecosystems with the aim of enhancing ecosystem carbon storage.

Abstract:The shrubs of islands also play a significant role in ecosystem since they are resistant to climatic conditions,especially to drought and salinity.The quantitative research on ecological relationship between vegetation and the environment at landscape and region scale has been developed rapidly,and that became one of the focuses of vegetation science.The paper aims to describe the composition and distribution of shrub in the southern five islands of Miaodao Archipelago and explain the influence of environment factors on the shrub population and give the reference for vegetation recovery.Based on the investigations of shrub vegetation species and environmental factors of southern five islands of Miaodao Archipelago in Shandong Province,the relationship between eco-environmental factors and the shrub species composition as well as their population structure in the survey area was investigated by using correlation analysis,canonical correspondence analysis (CCA),and two-way indicative species analysis (TWINSPAN).The result showed that:(1)27 shrub vegetation species belonging to 15 families and 23 genera were observed during the study period in the islands.The dominant families are Leguminosae and Moraceae.The highest frequency of the species is Vitex negundo var.heterophylla,which contributed up to 66.67% of the stations.Ziziphus jujuba var.spinosa and Grewia biloba var.parviflora were also found in more than 50% of the stations.(2)By using TWINSPAN,the population of shrub layer were classified into six types,they are Morus alba population,Robinia pseudoacacia-Cudrania tricuspidata population,Ziziphus jujuba var.spinosa population,Grewia biloba var.parviflora population,Vitex negundo var.heterophylla population and Amorpha fruticosa population.(3)Multivariate ordination techniques were used to analyze the effects of environment variables on the shrub community by CANOCO version 4.5.The environmental factors were analyzed,which include slope,aspect,coverage,soil water,pH,available nitrogen and available potassium,available phosphor,respectively.All of these environmental variables were ln (x+1) transformed before analysis except for pH.The results of canonical correspondence analysis (CCA) with forward selection indicates that tree coverage(F=3.19,P=0.004) and pH (F=2.01,P=0.014) were the most important environmental factors which influence shrub distribution in the southern five islands of Miaodao Archipelago during the study periods.

Abstract:The maize stalk of the third internode in the maturity stage is used as the research material.The research uses four ways,such as free-hand sectioning,frozen sectioning,paraffin sectioning,thin sectioning and compares the quality of the slice of different methods.This research lays the technical foundation for studying the relationship between the structure of maize stalks and lodging.The results show that free-hand sectioning method for getting the structure slice of mature maize stalks is a relatively convenient and rapid method,and the area of slice is relatively big.The slice is suitable for a wide range of observation and statistics.Frozen sectioning is a fast way to get the slice of mature maize stalks,and the area of slice is relatively small and the slice is suitable for a small range of observation.Thin sectioning is a good way to get perfect slice.It fits for high multiple microscope observation and small range of SEM observation to observe tissue structures,but the slice area is too small.Paraffin sectioning is not suitable for getting the structure slice of mature maize stalks.The research suggests that free-hand sectioning method is the most suitable way for observation and study of the structure of mature maize stalks.

Abstract:Michelia caudata M.X.Wu,X.H.Wu & G.Y.Li (Magnoliaceae),collected from the Baishanzu Nature Reserve in Qingyuan County,Zhejiang Province,China,is described and illustrated.This new species is similar to M.skinneriana Dunn and M.crassipes Law,but differs from the former in its leaves obovate to obovate-oblong,abaxial with dense fulvous villous,5-7.5×2.5-3.2 cm broad,apex caudate,vein ca.6 on each side;tepals oblong.It also differs from the later in its flowers pale yellow,gynophore 3-4 mm long.M.caudata is classified as Critically Endangered based on the IUCN Red List criteria.

Abstract:Five new geographical distributed species of Oberonia Lindl.in China,i.e.Oberonia falconeri,O.japonica,O.caulescens,O.menglaensis and O.langbianensis,are recorded.O.falconeri and O.japonica are found in Guangxi,O.caulescens and O.menglaensis in Hainan,and O.langbianensis in Xizang.The voucher specimens are deposited in the herbarium of the South China Botanical Garden,Chinese Academy of Sciences,Guangzhou (IBSC) and the herbarium of Guangxi Institute of Botany,Chinese Academy of Sciences (IBK).

Abstract:Two species and one subspecies of seed plants were newly recorded to Shaanxi,China:Elatostema ficoides Wedd.,Cotoneaster glaucophyllus Franch.and Clematoclethra scandens (Franch.) Maxim.subsp.scandens.