Abstract:The gene MaFLS encoding the flavonol synthase(FLS) involved into flavonol synthesis was cloned from Muscari armeniacum.The full length cDNA of MaFLS was 1 076 bp,and the open reading frame length was 999 bp,which encoding a protein polypeptide of 332 amino acids with a predicted molecular weight of 38.51 kD and pI of 5.09.The putative MaFLS displayed identities to the FLSs of Arabidopsis thaliana and Sorghum bicolor of 60% and 83%,respectively,and contained several typical conserved elements found in the 2-oxoglutarate- and Fe(Ⅱ)-dependent dioxygenases(2-ODD).Quantitative real-time PCR analyzed the expression profiles of MaFLS in different tissues.The results demonstrated that MaFLS was constitutively expressed in roots,stems and leaves,with particularly high expression in flowers.The cDNA of MaFLS was then subcloned into pET-32a and introduced into BL21(DE3),and the recombinant plasmid was successfully expressed in the condition of 0.1 mmol·L^-1 IPTG at 25 ℃ for 20 h.The molecular weight was found to be about 38 kD by checking with SDS-PAGE,nearly equal to the predicated.

Abstract:PHO2(encoding a ubiquitin-conjugating E2 enzyme),a negative regulator of phosphate transporter PHT1,is known to play a key role in the maintenance of phosphate homeostasis.In this study,nine members of ZmPHO2 gene family were identified from whole genome sequence of maize inbred line B73 based on PHO2 orthologs in Arabidopsis thaliana and Oryza sativa,which can be subdivided into at least three clusters based on phylogenetic relationship among several plants.The complete CDSs of all PHO2 homologs have been cloned from maize inbred line 178,and the conserved domain analysis revealed that all proteins have the same topology and harbor an ubiquitin-conjugating E2 enzyme catalytic domain (UBCc) which is fabricated of about 130 amino acids residues including a conserved cysteine.Based on quantitative real-time PCR,the transcripts of all ZmPHO2 genes were detected and exhibited different expression profiles in different organs and genotypes under low phosphate stress,but there are no distinct expression profiles among most of genes in the same tissue.Among them,ZmPHO2;H2 showed decreased expression levels in roots and increased expression levels in leaves at all sampled time points in maize inbred line 9782,indicating that ZmPHO2;H2 in maize may be involved in the regulation of phosphate transport from leaves to roots in order to maintain phosphorus homeostasis between the shoot and the root.

Abstract:Primers for phosphoethanolamine N-methyltransferase(PEAMT) gene from the halophyte Halostachys caspica were designed according to the EST sequence,and the full length cDNA of PEAMT gene was cloned by using RACE(rapid amplification of cDNA ends).The obtained cDNA was named as HcPEAMT.Sequence analysis indicated that HcPEAMT contains an open reading frame(ORF) of 1 482 bp,which encodes 494 amino acids with a molecular weight of 56.3 kD and a theoretical pI of 5.51.Conserved domain analysis showed that HcPEAMT has two separate conserved domains of S-adenosylmethionine-dependent methyltransferase,and each domain contains four motifs.Phylogenetic tree analysis indicated that HcPEAMT was closer to the halophyte of Salicornia europaea.Real time quantitative PCR results showed that the expression of HcPEAMT gene in assimilating branches and roots after salt stress for 3 h was rapidly up-regulated and reached the highest,which was 4.3-fold and 6.7-fold of that of the respective controls.When stressed by abscisic acid(ABA),the expression of HcPEAMT gene in assimilating branches and root reached the highest level at 3 and 12 h,and about 2.6-fold and 2.5-fold of the controls,respectively.These results indicated that the expression of HcPEAMT gene was strongly induced by salt stress,and also by ABA stress.Our results would help to clarify the relationship between HcPEAMT expression and plant resistance.

Abstract:Based on EST sequence,we cloned a gene named HbHEV3 coding prohevein.Sequence analysis revealed that HbHEV3 ORF cDNA length was 630 bp,encoding 209 amino acids.HbHEV3 shared high identities to prohevein from Hevea brasiliensis and other plants,had the typical structure of prohevein,containing a signal peptide,a conserved hevein/chitin binding domain and a Barwinn domain.The 1 050 bp promoter sequence of HbHEV3 was isolated and several regulatory elements related to hormone and stress responses were found in promoter region.The real-time PCR results indicated HbHEV3 was expressed in all detected organs,in which,the transcripts of HbHEV3 were higher in latex than that in other organs,and HbHEV3 was also induced significantly by ethephon.The results showed that HbHEV3 may be involved in ethylene-mediated defense responses and may play an important role in the process of latex aggregation.

Abstract:In this study,flagellin gene cloned from biocontrol strain Bs-916 (Bacillus subtilis) was introduced into rice by transgenic vector pCAMBIA1300,98 positive transgenic lines were obtained.PCR and RT-PCR test were carried out to detect the expression of target genes and 12 transgenic lines detected expression of fla gene.Subsequently,identification of disease resistance showed that three transgenic lines enhances resistance to Xanthomonas oryzae pv.oryzicola.It is clear from this research that fla gene can be used to control disease,provided a potential resistance gene for controlling bacterial leaf streak.These will shed light on their utility in crop improvement strategies.

Abstract:Orthoploidy Saccharum spontaneum L.is an important wild parent and gene pool related stress tolerance of modern sugarcane varieties,in order to understand their genetic background of resistant genes,we screened 50 clones of decaploid S.spontaneum L.with 63 sugarcane commonly used parents and 8 original species as control in genetic diversity by using these functional markers derived from DREB,AQP,HSP70,WRKY1 and arbitrary primers,of which are related to drought and high temperature tolerance.The results showed that:(1)119 bands were gained,110 of which belong to polymorphic ones,and the mean percentage of polymorphic bands and polymorphism information content reached to 92.44% and 92.53% respectively.The polymorphic level of decaploid S.spontaneum L.in the functional markers related drought tolerance was the richest;however the commonly used parents exhibited the most diversity in functional markers related high temperature tolerance.(2)In terms of Jaccard coefficient,decaploid S.spontaneum L.showed low mean value(0.541) and big distribution range(0.347-0.800) in the functional markers of drought tolerance,and most focused on the interval region of 0.400-0.600;for functional markers of high temperature tolerance,the biggest distribution range(0.238-1.000) appeared in commonly used parents,whereas the lowest value of coefficient(0.481) was found in the original materials mainly distribute with the interval region of 0.400-0.600.(3)By using UPGMA cluster method,all accessions could be divided into two big groups,one was consisted of decaploid S.spontaneum L.accessions,which exhibited evident difference from others;the other was composed by commonly used parents and original species.Overall,our results proofed that the decaploid S.spontaneum L.accessions have big genetic differences in functional markers of DBF,Aqua,SCB174 and SCB190 from commonly used parents and original species,and possess more abundant genetic variances in functional markers of drought tolerance.So in future,decaploid S.spontaneum L.resources should be utilized in improving stress tolerance of sugarcane varieties,especially in the impact of drought tolerance.

Abstract:Simple sequence repeats(SSRs) in the whole genomes of three wild tobaccos-Nicotiana tomentosiformis,Nicotiana sylvestris and Nicotiana benthamiana downloaded from the China Tobacco Genome Database(CTGDB) was analyzed by the bioinformatics method.A total of 153 357,196 493 and 278 784 SSR loci were mined out in the 2.14 Gb,2.44 Gb and 2.59 Gb of the three wild tobaccos’ genomic sequences,and the average distance between SSR loci was approximately 13.94 kb,12.42 kb and 9.31 kb,respectively.Almost all the SSR loci were distributed in intron domains and UTR domains(especially the 5′-UTR).Di-nucleotide and tri-nucleotide repeats,totally accounting for more than 80%,were the main motif types and the di-nucleotide was the most abundance in all SSRs.The highest frequency and the most abundance of SSR motifs configuration were A(T)_n.Except the mono-nucleotide motif type,the repeat number of the motif types was between 3 and 10.Three hundred SSR primer pairs randomly synthesized from three wild tobacco genomes were subjected to PCR using 8 tobacco accessions as materials which belong to 5 different species of the genus Nicotiana and the results showed that all the primer pairs could produce clear,stable and target bands,of which 80 SSR primers were polymorphic.The results indicated that SSR loci in the closer genetic relationship among tobacco species were highly conserved and could be used in the following research.It is meaningful to develop SSR primer pairs from wild tobacco genomic data for the application of relative genetic analysis.

Abstract:In order to reveal the genetic diversity and relationship and provide a scientific basis for the conservation and utilization of peach accessions in Guizhou,we evaluated the genetic diversity of 71 accessions by SCoT markers.The results showed that:(1)16 SCoT primers generated 192 bands and 156 polymorphic markers.On average,the percentage of polymorphic bands was 81.25% and amplification site of each primer was 12.(2)The Nei’s genetic diversity index (H) was 0.265 0±0.186 1,the Shannon index of diversity (I) was 0.400 3±0.254 3.The Jaccard genetic similarity coefficients among the accessions were between 0.400 0 and 0.852 5.(3)Cluster analysis with UPGMA method showed that 71 peach accessions in Guizhou could be grouped into six groups at Jaccard coefficient 0.65,and 2 varieties of Baihuatao,2 varieties of Xuetao and 2 varieties of Qingtao were proved to be a homonym,respectively.The substantial genetic diversity was identified among the peach accessions in Guizhou,and the peach accessions of homonym could be differentiated by SCoT markers successfully.

Abstract:We investigated pollen viability and stigmatic surface morphology and receptivity in sexual reproduction of Taraxacum ohwianum Kitag.,obligate apomicts of T.antungense Kitag.,facultative apomicts of T.mongolicum Hand.-Mazz.using germination in vitro and techniques of scanning electron microscopy and benzidine-hydrogen peroxide test.The result showed that:(1)Three kinds of dandelion stigma were dry stigma,single-celled papilla and belong to the primitive taxa.The phenomena of dichogamy and herkogamy appeared in dandelion.The papilla of T.ohwianum Kitag.was full grown and tight,T.antungense Kitag.was more wizened and T.mongolicum Hand.-Mazz.was the most wizened and rarefaction.(2)When stigma was in the Y-type ,the pollen germination capacity rate of T.ohwianum Kitag.and T.antungense Kitag.was the highest,at 67.3% and 19.8% respetiviely.The highest rate of pollen germination capacity of T.mongolicum Hand.-Mazz.was 23.3% when stigma was in stick-type.(3)The stigmatic receptivity of three kinds of dandelions was rising with flowering.When stigma was in the Y-type,it was the best pollination period on the kinds of dandelion and the rate of stigmatic receptivity in samples were 98.7%(T.ohwianum Kitag.),84.0%(T.antungense Kitag.),21.3%(T.mongolicum Hand.-Mazz.),respectively.There was transparent difference of sexual reproduction of dandelion and apomicts of dandelion in pollen germination capacity,papilla and stigmatic receptivity,which was an evidence of the redistribution of energy in sex organ of dandelion in long term evolution.

Abstract:The formation of microspore,development of male gametophyte and germination rate of pollen grains in long-style flower of Luculia pinciana(Rubiaceae) were observed by traditional paraffin section technique and cytology compression method.The results showed:(1)Long-style flower of L.pinciana had five anthers,and the anther was tetralocular.(2)The anther wall was composed of one epidermis,one endothecium,two middle layers and one to three tapetums from outer to inner.The development type of anther wall was of basic type and the tapetum belonged to glandular type.(3)During meiosis of the microspore mother cells,cytokinesis was simultaneous type,and the tetrads were mostly tetrahedral,occasionally found isobilateral.Meiosis of microsporocyte was asynchronous between different anther chambers.(4)Mature pollen grains were two-cell type at dispersal stage.(5)Microsporogenesis and male gametophyte development of long-style flower of L.pinciana showed normally,and was of bisexual flower.(6)The artificial germination rate of pollen grains between on the stigma of long-styled and short-styled flowers was (91.8±1.6)% and (93.2±1.1)% respectively,and did not differ significantly(t=1.585,df=8,p=0.152).It was suggested that pollen grains of long-style flower germinated normally between on the two stigmas.

Abstract:We studied the flower duration and reproductive allocation of Aconitum gymnandrum in different altitudinal populations on the Northeast of the Qinghai-Tibetan Plateau.Our results showed that:(1)The duration of individual flower in the high altitudinal population was remarkably longer than those in low altitudinal populations,and there was significant difference in flower duration between populations.(2)The biomass of flowers increased with plant size in the three populations.(3)The proportion of flowers in the total above ground biomass (reproductive allocation) increased along the altitude gradient.Consequently,we concluded that the importance of sexual reproduction in alpine environment was emphasized by the increased allocation of biomass to flowers,and prolonged floral longevity of A.gymnandrum along the altitude gradient suggested the mechanisms of compensation for the reduced pollinator availability and attraction to pollinators.

Abstract:The contents of proline and activities of key enzymes involved in proline metabolism in the leaves and roots were investigated for two wheat cultivar seedlings(differing in drought tolerance) exposed to PEG-6000 stress and recovery.The results showed that:(1)The root length and the root dry weight of ‘Pubing 143’(drought tolerant) were little affected little by PEG stress,whereas the root length and the root dry weight of ‘Zhengyin 1’(drought sensitive) decreased significantly.Under PEG stress the increasing range(75.0%) of proline content in the roots of ‘Pubing 143’ was more than that in ‘Zhengyin 1’(37.7%) at 36 h and the proline contents of both genotypes tended to be equal to their respective control after recovery from drought;(2)The activities of P5CS(synthesize proline from glutamate) and δ-OAT(synthesize proline from ornithine) increased significantly in the leaves of ‘Pubing 143’ under PEG stress,which indicated that two biosynthetic pathways were enhanced in the drought-tolerance cultivar ‘Pubing 143’ under PEG stress.P5CS activity increased while the change of δ-OAT activity was not obvious in ‘Zhengyin 1’ at 36 h,which indicated that the leaves of drought-sensitive cultivar ‘Zhengyin 1’ synthesized proline from ornithine primarily under PEG stress.Under PEG stress the activities of P5CS and δ-OAT were less affected in both wheat varieties roots;(3)PDH activity had a significant decrease at 36 h under PEG stress and increased significantly after recovery in the leaves of ‘Pubing 143’.PDH activity increased significantly compared with control in leaves of ‘Zhengyin 1’ under PEG stress.However,the activity of PDH decreased significantly in both wheat varieties roots.These results suggested that proline was mainly synthesized in the leaves of wheat and the accumulation of proline in the roots of ‘Pubing 143’ was associated with increased P5CS activity in leaves and transport of proline.

Abstract:We irrigated Distylium buxifolium with different concentrations of NaCl solution(0,80,100,200,300 mmol·L^-1),to evaluate salt-tolerance by indexes such as rate of injured area,relative water content,relative conductivity,chlorophyll content,malonicaldehyde(MDA) content,superoxide dismutase(SOD) activity,catalase(CAT) activity.Furthermore,the responses to moderate salt stress(100 mmol·L^-1 NaCl) of D.buxifolium(D) and its cultivars(D1,D4,D6,D7,D10,D13) were also compared.The results showed that:(1)The morphological and physiological indexes of D.buxifolium changed significantly under different salt concentrations.After 15 days,only those irrigated with NaCl solution below 100 mmol·L^-1 were still alive.(2)Under moderate salt stress(100 mmol·L^-1 NaCl),the rate of injured area of D1 and D13 is significantly smaller than that of other cultivars and the difference in all these indexes of D.buxifolium and its cultivars is significant.Meanwhile,the physiological response of D1 and D13 showed that the salt tolerance of these two cultivars might be higher than that of others.(3)The method of fuzzy cluster was used to evaluate the salt tolerance among different cultivars,which showed that the salt-tolerance order was D1>D13>D>D7>D10>D4>D6.Therefore,it is not appropriate to plant D.buxifolium in the area where salt concentration is above 100 mmol·L^-1.In light and moderate salinized areas,D1 and D13 would be the priority selections.

Abstract:As universal signaling properties,NO(nitric oxide) involves not only in plant growth and development,but also in plant response to abiotic and biotic stress.Until now,its function of osmoregulation is unknown.The study,using NaCl as a stress factor and tobacco suspension cells as experimental material,we investigated the effects of NO on osmoregulation of tobacco cells under NaCl stress.The results showed that:(1)Endogenous NO of tobacco cells was induced by NaCl stress.During 100 mmol·L^-1 NaCl stress,production of NO was rapidly induced in cultured cells in vivo,and reached at the peak(with 2 times of the control) in 1 h after the stress treatment ,then the production was deduced rapidly until 3 h,from then on,the amount of NO was increased gradually and maintained at a high level until 48 h.(2)Exogenous NO significantly enhanced osmotic stress tolerance ability of tobacco cells.150 μmol·L^-1 NO donor sodium nitroprusside(SNP) significantly improved vitality and regrowth of the cells by 78.6% and 63.2%,respectively,lowered cell death by 48.5%,when compared to that of non SNP treatments tress cells.Further study indicated that SNP treatments led to relatively lower cell solute potential and higher water potential,which was benefit for maintaining cell pressure potential under the stress.(3)Exogenous NO significantly improved the synthesis and accumulation of proline in tobacco cells under NaCl stress.150 μmol·L^-1 SNP increased proline accumulation of the cells by 25.9% due to effecting the activity of proline metabolic key enzymes,including the activation of glutamate dehydrogenase(GDH),arginase and ornithine aminotransferase(OAT),and the inhibition of proline dehydrogenase(PDH).Meanwhile,SNP also had corresponding effects on the expression of GDH,OAT and PDH genes.Our results suggest that NO involved in osmotic adjustment of tobacco cells to enhance salty tolerance,in which NO regulated proline metabolism of the cells was an important mechanism.

Abstract:Cucumber cultivar ‘Jinyou 4’ was subjected to low temperature treatment of 18 ℃/10 ℃(day/night) in the artificial climate chamber.The effects of exogenous melatonin(MT) on the growth and antioxidant system of leaves in cucumber under low temperature and weak light stress were investigated.The results showed that:compared with the control treatment,exogenous MT treatment could significantly promote the increment of plant height,wall thickness,flesh weight,dry weight;the chlorophyll content and root activity increased by 13.3% and 18.8%,GSH content and ASA content by 39.3% and 24.7%,respectively and increased SOD,POD,CAT,APX,membrane H⁺-ATP activities,while reduced MDA content and electrolyte leakage by 28.7% and 29.7% in cucumber seedlings leaves under low temperature and weak light stress.So we can conclude that exogenous MT treatment could raise the activities of antioxidant enzymes and matter,membrane H⁺-ATP activities,decrease the membrane lipid peroxidation,maintain membrane integrity and function,and improve the adaptability of cucumber seedlings under low temperature and weak light stress,the 200 μmol·L^-1 MT treatment was better.

Abstract:The present study aims to investigate the effect of 24-epibrassionolide(EBR) on the postharvest quality and antioxidant activity of eggplant fruit.With Brigitte eggplant fruits as material,the changes of chilling injury(CI),quality and antioxidant activity of eggplants were measured.Results showed that:(1)EBR treatment reduced CI index,inhibited respiration rate,and maintained tissue firmness of experimental samples compared with the control samples.The changes of calyx discoloration and total soluble sugar content of the eggplants were also significantly preserved by EBR treatment.However,EBR treatment showed no significant effect on titratable acid content.(2)The activities of SOD,CAT and APX in eggplant fruits during storage were also promoting by EBR,as well as lower content of H₂O₂ content.These results suggested that EBR improves storability and quality of eggplant fruit during cold storage,which might be due to the higher maintenance of antioxidant activity.

Abstract:With oilseed rape(Brassica napus) hybrid the ‘Qinyou No.7’ as material and plants of which after flowering were managed according treatments:shading leaf,shading silique and plucking leaf,such a field experiment was conducted to investigated photosynthesis characteristics and influence of the silique and leaf photosynthesis on seed yield,seed fatty acid content and seed fatty acid profile in this paper.The results showed that:(1)1000-seed weight,yield and fatty acid content of the seed declined by 54.7%,62.1% and 44.2%,respectively for the treatment shading silique,while contents of glucosinolate in the seed,as well as palmitic acid and octadecoic acid in fatty acid of the seed significantly increased and linolenic acid significantly decreased.(2)When leaves of the rape plant after flowering were shaded or plucked off,the seeds number per silique reduced by 11.7%,11.3%,and 1000-seed weight decreased by 22.5%,17.9%,respectively as so the seed yield per plant decreased by 35.3%,44.7%,while linolenic acid contents of seed fatty acid significantly increased and no notable influence on total contents of fatty acid in seed.(3)After flowering,green silique peel of the rape plant grew up to maximum area 1.54 double versus to area of green leaves,and solar radiation distribution a great quantity located in silique layer,where net photosynthetic rate.The transpiration rate of the silique were significantly high than that of the leaf,though contents of chlorophyll a,b and phytoxanthin in the silique were far lower.Actually the silique photosynthesis responding to photon flux density exhibited a higher light compensation point and higher light saturation point compared to the leaf.This infers that the silique is relatively endurable to stronger light radiation intensity in environment.Thus the study revealed that silique layer of oilseed rape accepted major light radiation during post-flowering stage and exhibited higher photosynthetic activity.The silique was main photosynthetic organ of rape plant and strongly influenced yield,fatty acid content as well as fatty acid profile of seed by photosynthesis.

Abstract:There is an interaction between the root fungal community and the plant disease.In order to uncover the interaction between the pine wilt disease and fungal community in the root of pine tree,we investigated the activity of root tips,the colonization rates of ectomycorrhizal fungi(ECMF) and dark septate endophytes(DSE),and analyzed the root fungal community structures and diversities of Pinus tabuliformis in the pine wilt disease damaged and undamaged areas through the isolation and identification of culturable fungi.The results showed that:(1)Not only the ratio of active root tips and ectomycorrhizal tips,but also the colonization rate of ECMF were significantly higher in pine wilt disease undamaged area than those in damaged area(P<0.05),while the colonization rate of DSE and the density of microsclerotium were lower than damaged area.The colonization rates of ECMF were significantly higher(P<0.05) than those of DSE in both of the two sample areas.(2)Based on the morphological and molecular characteristics of 131 isolates,they were finally identified as 23 species,in which,the dominant fungi were DSE,especially Phialocephala fortinii and Cryptosporiopsis ericae.(3)The two sample areas only shared 5 species,exhibited obvious difference in root fungal community structure and diversity.(4)In the pine wilt disease undamaged area,the richness(17) and Shannon-Wiener biodiversity index(2.012 0) of root fungal community,as well as the relative abundance of ECMF(8%) were higher than those in damaged area(11,1.197 9 and 1.6%,respectively),but the relative abundance of DSE(70%) was lower than that in damaged area(82.7%).Above all,it is suggested that the outbreak of pine wilt disease affected the root activity,ectomycorrhizal development,colonization of ECMF and DSE,as well as the fungal community structure and diversity.This is the first report about the relationship between DSE and pine wilt disease.Further research is required to make clear the influence of these isolates on the resistance of pine tree against pine wilt disease.

Abstract:In this study,we discussed the effect of seed size and altitude on the C,N,P contents of 53 Compositae plant seeds on the northeastern Qinghai-Tibet Plateau,and provided theoretical evidence for discussing the response of plants to environmental change.Seed size was defined by the average of three samples with hundred seeds,and element content of seed was measured with K₂Cr₂O₇ external heating method and flow injection analyzer.The results showed that:(1)There was significant difference in seed size of 53 Compositae plants,and a trend that seed size decreased with increasing altitude;(2)There was no significant difference in the C,N,P contents of seeds and their ratio among altitudes.However,there was a trend that the C,N content of seeds increased and the P content of seeds decreased with increasing altitude;(3)The C contents of seed did not change with seed size variation.While the N and P contents of seeds had significant negative correlation with seed size,and C/N,C/P and N/P ratios have significant positive correlations with seed size.The seeds with more relative contents of N and P are going with smaller seed size.This study suggested that the more accumulation of C and N in seeds could offer more energy and synthesis of proteins in the earlier stages of plants,and then would improve the ability of seedlings to resist harsh environment and enhanced the survival rate;the more contents of N and P in smaller seeds could offer enough proteins and ribosomes for the earlier growth of seedlings and help them to grow fast,and then would overcome the disadvantages due to smaller size.Thus,it is an adaptive selection that contents of C,N and P in seeds changed with seed size variation and altitude gradients.

Abstract:This research focused on the investigation of the vegetations in the coal mine subsided areas of Shenfu-Dongsheng coal mine region with different landforms.Based on the data obtained from the field survey,we measured the correlations between species diversity and soil properties in different geomorphic types and slopes.The findings showed that:(1)The plant species in Halagou mine(hilly-gully region) were richer than those in Dalita mine(windy desert area).Lespedeza davurica could be indicator plant in windy desert area,which succession mechanism conformed to the tolerance theory.Salsola affinis could be indicator plant in hilly-gully region,which succession mechanism conformed to the Promotion theory and competition.(2)After 12a subsiding disturbance,Shannon-Wiener index and Simpson index increased by 54.60% and 73.85% in two areas,respectively.The soil water content and soil urease activity increased by 8.64% and 57.14% in windy desert area,and soil organic matter increased by 47.73% in hilly-gully region.(3)After coal mining subsidence,soil catalase activity and volumetric water content decreased by 63.50% and 58.70%,the species diversity reduced significantly in the middle of slope in sandstorm area(P<0.05).Soil water content,soil nutrient and the species diversity increased in the bottom of slope in windy desert area(P<0.05).The vegetation diversity and soil physical and chemical properties changed together.(4)Significant positive correlation was observed of species diversity with soil water content in windy desert area.The species diversity was negatively correlated with soil organic matter content in hilly-gully region.

Abstract:Based on three types of degraded grassland:alpine meadow,alpine steppe and temperate desert-steppe in Qinghai-Tibet plateau,we analyzed the effect of fencing and grazing on different types of degraded grassland communities.The research results indicate that:(1)The abovegound biomass of three types of grassland increased by 48.1%,10.8% and 34.5%,respectively after five years of fencing.The responsing of underground biomass of three types of grassland were consistent with the aboveground biomass.(2)The propotion of upper-layer(0-10 cm) root biomass of alpine steppe and the root-shoot ratio of alpine meadow indicating a ‘clear decling trend’ while compared with the grazing land.(3)The gramineous plants,which occurred in a higher propotion in the total biomass in feacing grassland than it of grazing on alpine steppe and alpine meadow.Nevertheless,the proportion of troublesome weed in alpine steppe declined significantly and had no significant effects in temperate desert-steppe.

Abstract:The dynamics characteristics of population patterns in the vegetation succession are rarely explored.Scale,pattern and process of ecological succession are three intertwined concepts in modern ecology.Succession research will inevitably involve scale and pattern analyses.Species spatial patterns and interspecific associations at any scale can be analyzed based on point pattern analysis with spatial mapped points of individuals’ distribution.Therefore,it is suitable to discuss the relationships between species pattern in the vegetation succession process which have attracted much attention from ecologists.The aim of the present work is to study the spatial pattern formation and relative importance of intra and interspecific competition in dominant tree species of Betula platyphylla and Larix principis-rupprechtii in the vegetation succession process in Taiyue Mountain.The selected forest communities were treated as a time series of successional stages for the traditional space-for-time succession approach by applying the point pattern analysis.In the present research,ecological succession of B.platyphylla and L.principis-rupprechtii in Taiyue Mountain were dynamic characteristics and interspecific relationship.The series reflected the process from B.platyphylla as the monodominant community to B.platyphylla and L.principis-rupprechtii as the co-dominant communities and then to L.principis-rupprechtii as the monodominant community;Point pattern analysis and Monte-Carlo simulation test were used to analyze the spatial pattern of the two dominant species and their interaction relationship.The following conclusions were drawn.(1)The population structure of Taiyue B.platyphylla was spindle type,presenting a de-clining trend.By L.principis-rupprechtii age class structure is gradually replaced “pyramid” the growth of the population.(2)During the process from B.platyphylla to L.principis-rupprechtii as the monodominant community reflected,the spatial pattern of B.platyphylla changed from clumped to nearly random distribution,which was mainly caused by the colonization and expansion of L.principis-rupprechtii and the resulted interspecific competition.Besides,the spatial scale of L.principis-rupprechtii community gradually increased,with the species colonization and intraspecific competition as the major cause,which was driven by the intraspecific competition caused by the self-thinning effects and the colonization and expansion of L.principis-rupprechtii and the resulted interspecific competition.(3)In terms of the interspecific competition between the two species (B.platyphylla and L.principis-rupprechtii),no obvious relationship was found when B.platyphylla acted as the monodominant community,significant negative relationship was identified at the co-dominant stage,and no obvious relationship when L.principis-rupprechtii became the dominant species.The change of relationship between the two species was mainly driven by the intraspecific and interspecific competition for residual resources.

Abstract:We studied the vertical change characteristics of soil moisture of Robinia pseudoacacia plantations grown in different water ecological zones of the Loess Plateau,sampling at Ansai County of Shaanxi Province and Jingchuan County of Gansu Province,which lie in semi-arid hilly and gully region separately.The results showed that:(1)there were objective different under the different water ecological zones of the soil moisture vertical changing regularities.The peak of soil moisture appeared in the 20-30 cm deep in Jingchuan,then the soil depth was gradually increased,while the soil moisture was gradually decreased,And below the 200 cm deep layer tended to be stable(about 11%).The peak of soil moisture appeared in the 60 cm deep in Ansai,and below the 220 cm deep layer tended to be stable(about 5.5%).It showed that the soil moisture of Jingchuan is higher than that of Ansai.The effects of rainfall and forest roots on soil moisture in Ansai were greater than in Jingchuan,both on extent and depth.The deep soil moisture tended to a stable value,did not affecte by rainfall,roots consumption water etc.(2)The balanced model to describe precipitation infiltrating in the soil,it can good fit the vertical changes of soil moisture in the two zones(Jingchuan and Ansai).By establishing functions of the parameter t(month),a dynamic model was established to describe the changes of soil moisture with the time and the soil horizon depth.It was validated the dynamic model can be used to accurately calculate the soil moisture in different water ecological zones of black locust forest in the Loess Plateau,and has a higher application value.

Abstract:Based on the data of 45 plantation stand plots(1 000 m²) with five different stand ages(1a,2a,3a,5a,and 8a) collected from 50 sample sites in the main eucalyptus production areas in Guangxi,southwest in China,we studied the carbon storage and its characteristics of dynamic change.The result showed that:(1)The total carbon storage of Eucalyptus urophylla×E.grandis plantation ecosystem in the order of 3a(195.25 t·hm^-2)>5a(169.57 t·hm^-2)>8a(166.70 t·hm^-2)>2a(165.00 t·hm^-2)>1a(111.84 t·hm^-2),respectively;Carbon storage of different ages in different layers appeared:soil layer>vegetable layer>litter layer,underground>aboveground;Carbon storage of vegetable layer is 4.87-80.54 t·hm^-2,contributed 4.36%-48.31% to the total carbon storage of the ecosystems,and grew with ages;The carbon storage of litter layer is 0.92-3.25 t·hm^-2,only contributed 0.82%-1.91% to the total carbon storage,appears descend trend with ages;The order of carbon storage of soil layer is 3a(162.53 t·hm^-2,83.24%)>2a(141.55 t·hm^-2,85.79%)>5a(112.26 t·hm^-2,60.22%)>1a(106.05 t·hm^-2,94.82%)>8a(84.50 t·hm^-2,50.69%).(2)Tree layer stored the highest carbon storage(3.10-78.96 t·hm^-2)and comprised 63.64%-99.25% of carbon storage in vegetable layer.The carbon storage of tree layer in different organs was positively different,stem stored the highest carbon storage(1.58~68.84 t·hm^-2),and accounted to 50.90%-87.18%,which also increased with ages,the other organs distributing sequence of the carbon storage in tree layer is branch(4.97%-12.17%),leaf(1.97%-22.36%),root(5.87%- 14.57%),all decreased with ages.(3)The average annual net carbon fixation of Eucalyptus urophylla×E.grandis plantation is 11.73 t·hm^-2·a^-1,where 2a(16.03 t·hm^-2·a^-1) forest stored the highest,respectively,3a forest is a better species of carbon sequestration forestry with high capability of carbon deposition,8a annual net carbon fixation up to 11.96 t·hm^-2·a^-1,and flat with 5a.Therefore,to improve the eucalyptus forest ecological service function and reduce its negative effect will be conducive to the development and growth of eucalyptus plants.

Abstract:Understanding diversity is a hot topic in global ecology because of its significance to biodiversity conservation.To investigate the plant floristic diversity of Xianrendong in Liaoning Province,we conducted plot survey,floristic spectrum,diversity index,correlation analysis and cluster analysis.The results showed that:(1)It is abundant in species composition in Xianrendong,vascular plant consists of 803 species in 379 genera and 109 families,among which,39 species were of fern plants,belonging to 13 families and 17 genera,18 species were of gymnosperm,belonging to 5 families and 12 genera,and 746 species were of angiosperms,belonging to 91 families and 350 genera.It is notable in dominant family,the single-species and few-species genera of angiosperm are rich,which shows some relict phenomenon.The types of distribution are various and complex,the flora is ancient and it has not obvious phenomenon of endemic genera and species;the dominance of temperate elements is obvious and tropical elements are less.This means that it has something in common with tropical flora.(2)Compared with adjacent mountains,floristic Shannon-Wiener index are obvious differences,while Simpson index are not.Shannon-Wiener index of Xianrendong and Culaishan are quite high,Changbaishan and Baishilazi are not.(3)According to the relativity of different mountains flora,their correlation is significant at the 0.01 level,and the coefficients are between 0.811 and 0.997.Cluster analysis showed similarity between Xianrendong and Fenghuangshan,Qianshan,Wutaishan and Xiaowutaishan.The present data indicated that Xianrendong should belong to North China flora.These findings should guide conservation and management efforts to maintain species diversity.

Abstract:Neoalsomitra sarcophylla(Wall.) Hutch.is reported as a new record species of Cucurbitaceae from China.It is related to N.balansae(Gagnep.) Hutch.,but differs in its fruits 3-4 cm long,seeds 6-7 mm by 3-4 mm and shortly 2-horned at apex.In this study,matK,rbcL and psbA-trnH gene sequences of N.sarcophylla are acquired based on DNA barcoding technique and support the evidence of the species taxon after Blast.

Abstract:Acarospora molybdina,Acarospora verruculosa and Acarospora gobiensis were collected from Central Tianshan Mountains,Acarospora molybdina are new to China.The morphological and anatomical description of this three species were given.Photos of the thallus,apothecia,asci and ascospores were also provided.

Abstract:Impatiens alpicola Y.L.Chen et Y.Q.Lu(Balsaminaceae) is reported as newly recorded species to Chongqing,China.Its diagnostic characters,habitat and distribution are discussed.The voucher specimens are kept in Herbarium of College of Life Science and Engineering,Chongqing Three Gorges University.Meanwhile,a key to species of Impatiens from Chongqing was provided.

Abstract:Two genera and seven species of plant as provincial new distribution are reported in Yuanling,Hunan Province.Two newly recorded genera are Psilopeganum Hemsl.and Leptodermis Wall.The newly recorded species are Psilopeganum sinense Hemsl.,Leptodermis potaninii Batalin,Lycoris straminea Lindl.,Saxifraga granulifera Harry Smith,Biondia microcentra (Tsiang) P.T.Li,Adenophora trachelioides Maxim.,Odontochilus elwesii C.B.Clarke ex J.D.Hooker.Moreover,the newly recorded plants of phytogeographical significance are briefly analyzed.

Abstract:Elatostema huangjiangense W.T.Wang & Y.G.Wei and E.megacephalum W.T.Wang were reported as two newly recorded species from Guizhou Province,China.

Abstract:Pugionium Gaertn.was originally separated from the genus Bunias,and the phylogenetic tree based on ndhF sequences suggested that Pugionium is sister to Megacarpaea and,together they are closely related to Farsetia,Lobularia,Iberis and Ionopsidium.Since the establishment of Pugionium,a total of five species and one variety(i.e.P.cornutum (L.) Gaertn,P.dolabratum Maxim.,P.calcaratum Kom.,P.cristatum Kom.,P.pterocarpum Kom.and P.dolabratum var.platypterum H.L.Yang) have been described under this genus.However,the morphologically statistical methods and molecular evidence showed that only two morphological species,namely P.dolabratum and P.cornutum,can be warranted.Furthermore,the results based on different DNA markers with contrasting genetic surroundings suggested that the genetic divergences between these two morphological species are very distinct,although the interspecific differentiation time is not too long.It is highly likely that the two sister species of Pugionium diverged within the recent Pleistocene in association with the expansion of deserts in central Asia and northern China.In this paper,we reviewed the research history and latest progress on the phylogenetic origin,classification,genetic evolution of the genus Pugionium Gaertn.,and put forward to some problems,inspirations and prospects on the studies of this genus.