Abstract:A spike developmental atrophy mutant with deformed flowers (stems,leaves and other organ were developing normally),named as sda1,was first identified from wheat breeding lines.We observed the morphological characteristics of stamen,pistil,and the microspore stained with I-KI under a microscope.For genetic analyses,we generated an F₂ population by crossing sda1 with ‘Shaanmai 94’ wild type.We investigated the agronomic traits of F₂ population,and content of soluble sugar in spike and internode below ear and photosynthetic characteristics of flag leaf at filling stage were measured.By means of bulked segregation analysis and small population-based linkage analysis using the published SSR markers we mapped the gene.The results showed that:(1)The stamen and pistil developed atrophy and the microspore of sda1 was abortion.(2)The original strain of mutant segregation tests suggested that,the mutant phenotype was controlled by a single recessive nuclear gene named as SDA1 (spike development atrophy 1).(3)The mutant heading date delayed 4 days comparison with the wild type;and soluble sugar content of internode below ear and spike in mutant wheat were significantly increased 30.6% and 11.0% than those in normal wheat at filling stages.However,the heading duration was 8 days both the mutant wheat and the normal wheat;and the photosynthetic characteristics of flag leaf between mutant and normal wheat were not detected.(4)The gene mapping analysis suggested that,SDA1 locus was preliminarily mapped between marker WMC398 and BARC136 on the chromosome 6B with the genetic distances of 2.2 cM and 2.1 cM to the two markers.It is speculated that SDA1 is a pleiotropic gene controlled the heading date and the spike organ development,and also affects the transformation and utilization of soluble sugar.

Abstract:A full-length sequence of BnHSFA4a was obtained from Brassica napus by RT-PCR and RACE for the first time,named BnHSFA4a (GenBank accession No.HQ435241).The full length of BnHSFA4a is 1 667 bp,encoding 389 amino acids.Homology analysis of amino acid sequence of BnHSFA4a showed 82% similarity with AtHSFA4a.Multi-alignments of 33 different kinds of HSFs showed high similarity more than 60% at 100 to 190 aa in their amino acid sequences.Prokaryotic expression showed the recombinant vector can express the prospective protein.The semi-quantitative RT-PCR indicated that the expression of BnHSFA4a was followed by the expression of BnGOLS1,which is in accord with hypothesis that BnHSFA4a regulates BnGOLS1.It suggests that BnHSFA4a may play an important role in the mechanisms of seed desiccation tolerance through regulating the expression of BnGOLS1 .

Abstract:A cDNA-AFLP approach on Brassica napus L.seeds was used to identify genes associated with desiccation tolerance during the seed development and germination.After compared with the database of NCBI,among the 394 specific transcript-derived fragments (TDFs) obtained with 128 primer pairs,189 TDFs presented significant similarity with the functional genes which can be classified into transcription factor,basic metabolism,stress resistance,signal transduction protein and so on.Using a RT-PCR approach,the significance of difference was confirmed.It indicated that Ubiquitin,Caleosin,Oleosin,HSP and some of the transcription factors can be induced by the seed dehydration.All the findings revealed that the progress of dehydration happened in seed development and germination is very complicated and involved in many fields of the plant life.

Abstract:Different expression genes in the dedifferentiation progress with Affymetrix chips were analyzed.(1)According to data of the chips,there are 4 222 different expression genes,1 684 of them are up-regulated expression and 2 538 genes are down-regulated.(2)The genes relation to cell dedifferentiation according the data of chip and semi-qualitative RT-PCR were further identified and screened,and SMB (SOMBRERO) gene was firstly isolated.(3)SMB gene expression pattern was analyzed with real-time PCR.The gene expression level of SMB increased gradually with the time undergoing cell dedifferentiation.(4)The function of SMB gene undergoing plant cell dedifferentiation was further demonstrated.Test and verify mutant SMB gene in Arabidopsis can affect the procession of cell dedifferentiation and the ability of forming callus.This research demonstrated that SMB gene involves in cell dedifferentiation of Arabidopsis thaliana.

Abstract:In the base of truncated Flavanone-3-hydroxylase gene (TrF3H) achieved from full-length cDNA library of tartary buckwheat which was in seed-filling period,prokaryotic expression vector pET47b-TrF3H with truncated coding region of F3H（TrF3H）was constructed and transformed into E.coli Rosetta (DE3) plysS.After the overexpressed target protein purified by cobalt chelating chromatography,the high titer polyclonal antiserum raised against rabbit was obtained.The results demonstrated that the TrF3H had been expressed in E.coli in the form of inclusion bodies and western blotting analysis showed the raised antibody could specifically react with the antigen while native F3H existed in immature seed protein.These results laid the basis for further exploration of the functions of F3H in tartary buckwheat.

Abstract:Sucrose synthase is a key enzyme in sucrose metabolism.In this study,we investigated the function of SUS family in Arabidopsis by using reverse genetics method.AtSUS3 was silenced in mRNA level by RNA interference technology.Using pure transgenic lines,we observed plants bolting rate,analyzed SUS,SPS,INV and CesA activity,detected soluble carbohydrate content and tested expression pattern of glycometabolism genes.(1)Comparison to wild plant,transgenic lines promote early bolting on an average of 2~3 d and ahead of time to complete bolting about 3~4 d.(2)Growth days after flowering (DAF) have significant impact on sucrose and glucose contents,but the impact on the fructose content does not significantly.5 DAF,the glucose content of the wild-type and transgenic line SUS3-15 is significantly higher than that of transgenic line SUS3-2.15 DAF,the glucose content of the transgenic lines is significantly lower than wild-type.(3)The growth days after flowering have a significant impact on SuSy,SPS and INV activities.With time extending,SuSy activity in the wild-type is significantly lower than that in the transgenic lines,but the SPS and INV activities are opposite.(4)We also detected that interfering AtSUS3 has different degrees impact to mRNA expression pattern in other sucrolysis genes.In 5 DAF transgenic siliques,the expression of AtCesA1,AtCesA7 and AtCINV1 are higher than that in wild siliques.In 15 DAF transgenic siliques,the expression of AtCesA1 and AtCesA7 are also higher than that in wild siliques,but the expression of AtCINV and AtCwINV are lower than that in wild siliques.These results indicated that transgenic plants have not developed anormally in normal culture conditions after AtSUS3 with RNA interference.It might be promote whole SuS activity to improve by other homologue SuSy genes and sucrolysis genes expression lever increase.All these reasons might facilitate siliques maturation.

Abstract:The DNA sequence and cDNA sequence of Malus domestica EIN2 were amplified by PCR and RT-PCR,respectively.Bioinformatic analysis of the nucleotide and sequence of EIN2 was performed.The results showed that:(1)The sequences of M.domestica EIN2 amplified by PCR and RT-PCR both are the same,without intron in it.The M.domestica EIN2 was 4 378 bp,containing one opening reading frame of 3 282 bp and coding 1 093 amino acid residues.The molecular weight of M.domestica EIN2 is 118.9 kD,and its theoretical pI is 5.52,and the protein probably is a liposoluble and lyophobic protein.(2)The multiple sequence alignment indicated that the deduced amino acid sequence of M.domestica EIN2 shared 52%,79% and 62% identity with EIN2 of Arabidopsis thaliana (AAD41077.1),Prunus persica (ACY78397.1) and Vitis vinifera (CAN66374.1),respectively.(3)The constructed phylogenetic tree shows that A.thaliana,Thellungiella halophila,Cucumis melo and Populus trichocarpa were clustered together,while P.persica,Petunia hybrida and Solanum lycopersicum were clustered to another group.V.vinifera,M.domestica and Medicago truncatula were clustered in separate groups,respectively.And M.domestica EIN2 is closely related with the homologous genes of P.persica,et al,and the relationships of it with the homologous EIN2 genes in A.thaliana and T.halophila were remote.

Abstract:This study used homologous sequence cloning method to clone the full length of sucrose phosphate synthase gene in Dendrobium officinale and induce prokaryotic expression.Results were as follows:(1)The cDNA is 3 502 bp in length containing an open reading frame of 3 186 bp encoding 1 061 amino acids.The GenBank accession number is JF423929.On the amino acid sequence level,this gene shows the highest similarity (93％) with SPS gene of O.goldiana.The similarity of SPS gene were higher than 60% with other plants.(2)The gene was expressed in E.coli with molecular mass of 118.7 kD,which was consistent with the speculation of Biotech.(3)Secondary structure includes helix,beta-folding and coil,which is a hydrophilic,transmembrane and unstable proteins.There are two function structure domains which are sucrose synthesis functional domain and glycosyl transfer function domain.This study provides the theory basis for research the gene spatio-temporal expression and function,polysaccharide synthesis mechanism and metabolism path in D.officinale.

Abstract:With the aim of molecular marker assisted selection for seed width in pumpkin (Cucurbita maxima),193 progenies of F₂ generation derived from a cross between the large seed variety ‘0515-1’ and the small seed variety ‘0460-1-1’ in the present study were screened using AFLP and SSR molecular markers for their polymorphic sites,and a genetic linkage map containing 84 polymorphic loci was constructed for identifying seed width trait.The genetic linkage map consisted of 12 linkage groups,and was,totally,683.50 cM in length.The average distance between adjacent loci was 8.13 cM.Further analysis using the composite interval mapping method showed that 4 QTL spread over the 3 linkage groups,the percentage of phenotypic variation explained by individual QTL ranged from 2.87% to 29.68%.

Abstract:The morphology of spores of 7 genera,34 species of Aspidiaceae from China was examined using scanning electron microscope (SEM).The spores of Aspidiaceae are monolete,bilaterally symmetrical and the aperture is 1/2～2/3 of the spore diameter.The spores are often elliptic in polar view,and hemispheric,super hemispheric or fabiform in equatorial view.The length of polar axis is about 18～38 μm.The length of equatorial axis is about 23～57 μm.The spore ornamentations of Aspidiaceae are divided into four types.i.e.Lophate,Alate,Echinate and Auriculate.Sometimes there are spinelets,particles and holes on surface ornamentation.The classification of Aspidiaceae based on the spore morphological characters differs from that based on the sporophyte characters.The ornamentations types are interlaced between genera of Aspidiaceae.MAARTEN J.M was supported to redistribute Aspidiaceae and Dryopteridaceae.

Abstract:To study the fiber cell morphology,structure and its correlation with yield and physical properties of wild plant in Boehmeria,the determination of economic traits and microscope observation of the cell morphology of the cross-sections and isolated fiber were conducted in process maturity approach with 13 kinds of Boehmeria plant as test material.The results showed that:(1)Fiber cell morphology in germplasm of wild ramie was consistent with the cultivation of ramie,were mostly circular,polygonal,oval,and kidney line,of various shapes and sizes;(2)Fiber cell diameter,lumen diameter and the total number of fiber cell in stem cross-section showed varying degrees of positive correlation with raw jute yield,but they were significantly less than the control cultivars,which indicated that it was difficult for the wild Boehmeria germplasm to have good improvement to increase production;(3)There were not significantly negatively correlation between segregation fiber cell length,width,wall thickness,nodule number and fiber fineness,and the cell length,width of wild Boehmeria germplasm was significantly less than the cultivars of ramie,which indicated that the Boehmeria wild material had important application value in the fine fiber gene breeding areas and improving fiber quality in cultivars of ramie.

Abstract:Through paraffin production method and optical microscope technology to measure ten xeromorphic structure indexes,including leaf thickness,corneous layer thickness,main vein thickness,upper palisade tissue thickness and so on of Amygdalus pedunculata Pall..The materials are from Hebei,Wushenqi,Guyang,Shenmu,Yuyang areas,which are divided into CK and drought treatment two groups.Results showed that:(1)Hebei region’s drought damage index is the highest,indicating it was damaged badly,and with worst drought resistance performance;the indexes of Shenmu and Guyang areas are under Hebei and Wushenqi areas;and Yuyang area’s index is minimum,with the biggest ability to resist drought damage.(2)The five areas of A.pedunculata Pall.are similar in leaf structure.They are all total with cuticle,the vascular bundles are bicollateral.The palisade tissues are well developed with one or two layers.Analysis of variance showed that the blade of Hebei region is the most thin in leaf anatomical structure determination,both the upper epidermis and horny layer are minimum.They only have a layer of palisade tissue cells arranged more loose,scattered irregular arrangement of spongy tissue cell with bigger cell gap,and smaller principal vain diameter with narrow channel function.The blade of Yuyang area is on the contrary.They have double palisade tissue.The first layer of cells elongated closely packed and the second layer is shorter with developed vascular tissue,containing more water storage cells (mucus cells and crystal cells).(3)According to the comparison of leaf drought damage index and structure’s index,and the method of membership function,we get the sequence of drought resistance was as follows:Yuyang area>Shenmu area>Guyang area>Wushenqi area>Hebei area,which provides the reference for regional introduction and theoretical basis for breeding of A.pedunculata Pall..

Abstract:It was found that the bud bracts filled with dense pubescence of most plants in high altitude at low temperature in early spring was morphological characteristics during the investigation of the Pan-Himalayas plants.By study on the Salix,the relationship between dense of pubescence on bud bracts and the altitude was discussed;the temperature changes of inner and outer buds were observed by using infrared thermometer and infrared thermal imager,and temperature of Magnolia flower buds which located in temperate regions was measured under the light of the sun or overshadow conditions.In addition,the inside and outside temperatures of Salix flower buds and Magnolia flower buds in different light intensity were compared by using Li-6400 XT portable photosynthesis system,and the relationship between the intensity of light and temperature changes of flower buds was studied.(1)It was indicated that the dense of pubescence on bud bracts are related to altitude and light intensity,and the higher the altitude,the denser pubescence on bracts,for the pubescence on buds bracts absorbed heat in the sunlight.(2)The pubescence play a role in keeping the internal of buds warm,and to prevent the young flower bud in winter or early spring from cold.It led us to extend the concept to a larger group of plants,namely “pubescence plants”,which are characterized by very dense pubescence on tightly packed bracts of buds or inflorescences.It was indicated that this character is a result of a convergent adaptation for low temperature in early spring.

Abstract:Seedlings from the tetraploid Cymbidium hybrid and the original diploid Cymbidium hybrid were exposed to high temperature（40 ℃/30 ℃,12 h light/day).The effects of stress on plant physiological and biochemical characteristics,including the chlorophyll content,the membrane damage degree,the osmosis-regulation substance content and the activities of protective enzymes,were analyzed to assess the difference of heat resistance between the diploid and tetraploid.The results showed that high temperature stress decreased the chlorophyll content of both seedlings,while tetraploid showed less decrease.The malondialdehyde (MDA) content was increased in both diploid and tetraploid plants,but diploid increased more.The O^-·₂ release rate was decreased in both diploid and tetraploid seedlings and decreased faster in diploid.The increasing ranges of leaf proline content,soluble sugar,soluble protein,and activities of catalase (CAT) and superoxide dismutase (SOD) were all higher in tetraploid,while decreasing ranges of POD activity was notable in diploids.Our results indicated that tetraploid was more powerful than diploid in heat resistance because tetraploid showed higher competence in cell osmosis-regulation,protein synthesization and stabilization,and reactive oxygen species (ROS) elimination.

Abstract:The muskmelon cultivars,‘Zhongtian No.1’ was used to investigate effects of number of top vine and fruit on plant growth,leaf antioxidative characteristics,yield and quality of muskmelon.The six treatments are as follows:V1F2,V2F2,V3F2,V1F3,V2F3,V3F3,one fruit without top vine was set as CK.The results revealed that:(1)Increased fruit number leads to inhibited growth in muskmelon plant,which was seen in stem diameter,average node length and functional leaf length;(2)O^-·₂ production rate and MDA content was higher with two fruits than that with three fruits,while O^-·₂ production rate was lower than that of CK and MDA higher than that of CK;SOD activity in V2F2 was higher than that in CK and other treatments,and a minimum was seen in V3F3.POD activity in V2F2 was lower than that in CK and other treatments,and a maximum was seen in V3F3;(3)Increased side vines with 2 fruits per plant led to improved fruit quality while a worse quality was seen with 3 fruit setting per plant.In this study,V2F2 was favorable for plant growth,antioxidative capability enhancement,leaf senescence delay,and consequently,increased per-plant yield and improved fruit quality.

Abstract:In this study,three different strains of Dendrobium candidum seedlings were sprayed with different concentrations sodium selenite (Na₂SeO₃) solution on leaves and treated with low temperature stress under artificial temperature control growth conditions,then the effects of exogenous selenium on cold tolerance and recovery growth ability of D.candidum seedlings and their relationship with the relevant antioxidant physiological indexs were discussed.The result showed that:(1)Under low temperature stress,chlorophyll content,MDA content and proline content in the D.candidum seedlings with superior cold tolerance changed less than the strain with weaker cold tolerance.(2)Appropriate concentration of exogenous selenium(0.05~0.10 mg·L^-1) spraying treatment could alleviate the effect of chlorophyll degradation,also caused seedling antioxidant GSH-AsA activity significantly increase,meanwhile it increased the proline content and decreased the MDA content,improved the cold tolerance of D.candidum seedlings.However,the high concentration of exogenous selenium (＞0.20 mg·L^-1) treatment leaded to an opposite result.(3)After low temperature stress treatment,exogenous selenium (0.10 mg·L^-1) treatment could decrease the AsA content of seedlings significantly,but could promote the synthesis and accumulation of GSH,and effectively protected the comprehensive antioxidative capability of D.candidum ‘ZD-1’ seedlings in recovery growth period.

Abstract:Temperature and water are two important environmental factors that influence flavonoid synthesis in ginkgo (Ginkgo biloba) leaves.In this paper,we studied three temperature levels (T₁,5 ℃～15 ℃;T₂,15 ℃～25 ℃;and T₃,25 ℃～35 ℃,respectively) and three soil water content levels (30%～35%,40%～45% and 55%～60% of field water capacity,respectively) on flavonoid content and activities of L-phenylalnine ammonialyase (PAL),cinnamic acid 4-hydroxylase (C4H),and 4-coumarate-CoA ligase (4CL).Results showed that:(1)A significant difference for PAL,C4H,4CL and flavonoid was found in ginkgo leaves under the temperature and water stress (P＜0.05).These three enzyme activities increased with the stress.However,the results were still different in leaves for each enzyme activity.(2)High temperature (T₃) and low temperature (T₁) increased PAL,and the T₁ only increased C4H.For 4CL,in 14 and 28 day,water was the main factor to affect 4CL,but 42 day later,the temperature became the main factor.(3)The flavonoid in ginkgo leaves was decreased with stress (P＜0.05).Same as 4CL,water was the main factor in early days,but temperature was the main factor in later days.(4)From the analysis of relationship,PAL,C4H,4CL and ginkgo leaves biomass were negatively correlated with the flavonoid content.Although the temperature and water increased these enzyme activities,the flavonoid content in ginkgo leaves still decreased.

Abstract:Using the tobacco variety ‘Yunyan 87’ as experimental material and natural lighting for control,the effects of supplemental lighting on leaf growth,chlorophyll content,photosynthesis,chlorophyll fluorescence,and light response curves in tobacco plants was investigated by additional night artificial lighting for 1,2 and 3 h in this study.The results showed that,as compared with the natural lighting,the treatments with supplemental lighting for 2 h obviously promoted leaf length and width,and plant height,the treatments for 1 h and 3 h showed insignificant effect.These supplemental lighting treatments from 1 to 3 h remarkably decreased specific leaf area (SLA) and increased contents of chlorophyll a,b,chlorophyll a+b and carotenoids,and these changes for 1 h and 3 h treatments were less than 2 h treatment.The treatments with supplemental lighting for 1 h and 2 h obviously raised net photosynthetic rate (P_n),stomatal conductance(G_s),intercellular CO₂ concentration(C_i),3 h treatment had little effects.The supplemental lighting treatments significantly enhanced optimal quantum yield of Φ_PSⅡ(F_v/F_m),actual photochemical efficiency of PSⅡ(Φ_PSⅡ),and photochemical quenching (q_P),lowered non photochemical quenching (NPQ),but showed little effect on initial fluorescence intensity Fc.Maximum net photosynthetic rate (P_max) and light saturation points (I_sat) were both raised,and light compensation point (I_c) was not affected obviously under these supplemental lighting treatments.These results indicated that proper supplemental lighting time could enhance the growth of tobacco leaves,accumulation of dry matter,chlorophyll content and photosynthesis,relieve the photoinhibition phenomenon,make full use of light energy,and improve the efficiency of photosynthesis in tobacco leaves.

Abstract:By setting up a controlled-experiment with soil water content and fertilizer,the seedling were analyzed to investigated the effects of environment on the trade-off and lignification and to understand the reasons and mechanism of the seedling and the seed regeneration.The results showed that:(1)Populus euphratica seedling’s growth of trade-off was mainly reflected in biomass distribution strategy.However,the main root length to height ratio was not significantly different.(2)Under continuous water treatment,drought stress increased root to shoot ratio.The root to shoot ratio of the 15% water content level increased by about 75% and 93% of those under 20% and 30% water content levels.But drought stress decreased biomass,for example,the biomass of 10% water content level decreased by about 53.4%,89.2%,78.6% than other levels.With intermittent water treatment,drought stress also increased root to shoot ratio.The root to shoot ratio of the 15% water content level increased by about 34% and 38% of those under 20% and 30% water content levels.In addition,drought resistance can also impact lignification with both water treatments.(3)Applied nitrogen and phosphorus could improve root to shoot ratio and lignification significantly,but excessive nitrogen decreased biomass.The sensitivity of P.euphratica seedlings to water and fertilizer conditions and the growth weighed ability are key factors to create seeds and maintain population.Therefore,the soil water and fertilizer conditions play an important role for the seed germination and seedling growth of P.euphratica.

Abstract:In order to understand the interaction of different microbial agents and microbial organic fertilizer,we selected susceptible wilt cucumber cultivar ‘Jinyan 4’ as the test materials.The cucumber seeds were sowed into three different seedling substrates:commodity matrix,peat-vinegar residue (volume ratio of 1∶1) and peat-vermiculite (volume ratio 1∶1),which were added “bio-organic fertilizer” (Ba),the mixed microbial agents E and the single agent B006,respectively.Then the 28 days aged seedlings were transplanted to the commodity matrix and were infected with wilt pathogen.The results showed that appropriate amount of Ba,B006 and E in all substrates could improve the cucumber seedling’s growth and chlorophyll contents.And adding microbial agents in commodity matrix was the best.Commodity matrix with 30 g Ba the plant height,stem diameter,leaf area,root volume of cucumber seedling was 1.07,1.09,1.50 and 1.30 time of CK,and the stem and leaf fresh weight,stem and leaf dry weight and root dry weight was 1.28,1.41 and 1.34 time of CK.Commodity matrix with 10 g E,the contents of Chl a,Chl b and total Chl of cucumber seedlings was 1.81,1.93 and 1.83 time of CK.Ba,B006 and E could improve the number of bacteria and actinomycetes in the bulk and rhizosphere but reduce the number of wilt pathogen.Substrate with B006,the number of bacteria and actinomycetes in bulk and rhizosphere substrate was 2.10,1.96,2.32 and 1.92 time of CK,in separately,and the number of pathogenic bacteria in bulk and rhizosphere only 19.05% and 41.00% as controls.Adding B006 and Ba wilt incidence was reduced by 37.00% and 25.00% compared to the control,respectively.The results showed that commodity matrix with 30～40 g Ba is effective in improving the quality of seedlings and adding right amount of Ba or B006 could improve plant disease resistance in growing stage.

Abstract:Elodea canadensis was grown in water with constant gradients of total nitrogen (TN) and phosphorous (TP) concentrations.In present study,the growth status of E.canadensis and the capacity of removing phosphorus and nitrogen in greenhouse were evaluated by hydrotropic experiments of summer season.The results showed that E.canadensis could growth well under lower nutrient concentration (TN 1.0～5.5 mg·L^-1,TP 0.3～1.3 mg·L^-1）while its growth were partial inhibited under the enriched nutrient concentration (TN=8.0 mg·L^-1,TP=2.0 mg·L^-1 ).The nutrients removal rates of E.canadensis were enhanced with the increase of the nutrient concentrations.After 50 days treatment,the removal rate of nitrogen by E.canadensis were 55.88%,85.51%,88.18%,93.57%,95.97%,respectively and phosphorus were 47.55%,74.31%,57.75%,79.23%,74.92%,respectively.Based on our results,we can conclude that E.canadensis shown removal effects of phosphorus and nitrogen in the hot weather during summer with tolerance to higher concentration of nitrogen and phosphorus to some extent.The removal efficiency of E.canadensis is higher for nitrogen than that for phosphorus.

Abstract:By using point pattern analysis,we analysed the age structure,spatial distribution patterns and associations of different age-class individuals of four Taxus yunnanensis populations in Lanping County,Northwest Yunnan Province.(1)Forest gap and human disturbance were important factors which influenced age structure of four T.yunnanensis populations.The age structure of population which had a small forest gap indicated stable type and which had a larger forest gap indicated growth types.The age structure of population showed decline type when community structure integrity had no forest gap or population with comparatively larger human disturbance.The decline types were short of individuals of seedling,saplings and small trees and had regeneration difficulties to certain extent.The size of forest gaps is an important factor of population regeneration.(2)Human disturbance,natural environment and its biological characteristics affect spatial distribution patterns of 4 populations.There was a significantly aggregated distribution at overall and every growth stages of population 1.Population 2 and 4 all displayed that aggregated distribution in small scales and randomly distribution in larger scales.Population 3 indicated changes from aggregated distribution to randomly distribution and then converted to aggregate distribution with development of scales.(3)Seedling,small tree and medium tree of population 2 showed aggregate distribution in a small scale and more randomly distribution in a larger scales.Small tree of population 3 showed both aggregated distribution and randomly distribution and medium tree and old tree displayed aggregate distribution in all scales.The degree of aggregation of population 4 reduced gradually with progress of growth stages.(4)Different growth stages of 4 populations showed significantly or close positive correlation.Intraspecific competition is weak which had advantages of population maintain.

Abstract:In Northwest Hu’nan Province,there are kinds of valleys,which are firstly classified into three gradients,i.e.“U” (e.g.Mengdonghe River Valley),“V” (e.g.Dehang Valley) and “” (e.g.Xiaoxi Valley),according to the included angle between slope and base of valley,width of its base and runoff in this paper.Regarding the three valleys mentioned above as our study regions,we compared seed plant diversity composition and flora constituent structure among these different habitat conditions,and then revealed the characteristic and regularity of plant component corresponding to the alteration of gradient of valley.The detailed results are as follows:(1)Species composition shows obvious difference in three gradients of valley,between which the comparability coefficients get up to more than 80% and 70% at the family and genus levels respectively,while only about 50% at species rank.(2)Along with the gradient of valleys weakening,the portion of tropical component tends to decrease,accounting for 54.56% (Mengdonghe River),46.44% (Dehang) and 44.11% (Xiaoxi).Meanwhile the temperate component is with a trend of ascent of 40.00%,50.76% and 50.88%,respectively.Through this study,we find that all of the three valleys are both a refuge for relict taxa and a cradle for breeding new species although there are certain gradient and difference among them.Also,they are distinguished areas where seed plants distribute in Northwest Hu’nan Province.

Abstract:The flora of 984 species,147 genera of Orchidaceae from 38 regions of China as well as the tendency of R/T (tropical/temperate character) value with the latitudes were analyzed.All the flora types were clustered with SPSS 20.0.The results revealed that:(1)147 genera can be categorized into 11 types and 9 subtypes,and its 984 species into 12 types and 6 subtypes.(2)At generic level,the R/T values decreased along with the increase of the latitude in general,and 23 regions are tropical,13 regions are temperate,and the other two regions-Emei Mountain and Jinfo Mountain,are equal with tropical and temperate character.Whereas,at species level,the R/T values of all other regions just decreased in response to the increase of the latitudes and show a very strong tendency of latitudinal direction zonality,except for Erxianling,where has the most obvious tropical character due to its unique limestone geology.(3)There is a significant differentiation of the areal-type between genera and species.The Tropical Asia (24.71%),North Temperate (19.14%),and Tropical Asia to Tropical Australia (15.32%) are the top three areal-types among all the 147 genera of Orchidaceae in these 38 regions.But in contrast,besides the Tropical Asia (30.28%),the rest two main areal-types among the 984 species of Orchidaceae are the Endemic to China (26.89%) and the Sino-Japan (12.85%).(4)The cluster analyses indicate that species level is better than the genera level in understanding that the nearer the geographical latitude is,the more similar the flora should have.

Abstract:By using classic taxanomic methods,the author studied more than 360 speciments of Syntrichia Brid.(Pottiaceae) which were collected form different parts of Xinjiang Uyghur Autonomous Region from 1989～2012.The result of the study shows:(1)There are 11 species of Syntrichia distributed in Xinjiang,among them 3 species are new-record to Xinjiang.(2)The 3 new record species are Syntrichia norvegica,S.bidentata and S.caninervis var.spuria,among them S.bidentata is listed as one of the Chinese endangered Bryophytes.(3)It offers the geographical distributions of the 11 species,figures and descriptions of the new-recorded species and also a key to the Syntrichia in Xinjiang.

Abstract:One species,Paris vaniotii H.Léveillé,and one varity,P.polyphylla var.alba H.Li & R.J.Mitchell,are reported as new records from Sichuan,China.Their geographic distribution characteristics are both narrow area distribution and disjunction distribution.The discovery of new distribution in Sichuan has important significance for P.vaniotii,which was endangered in it’s holotype origin region.

Abstract:During the investigation of biodiversity of diatoms from Great Xing’an Moutains,more than six hundreds samples were collected and studied.Totally,10 taxa from Naviculaceae were newly recorded in China which belong to four genera.They are:Frustulia crassinervia (Brébisson) Lange-Bertalot & Krammer;Neidium ampliatum (Ehrenberg) Krammer,Neidium apiculatum Reimer,Neidium binodeformis Krammer;Navicula upsaliensis (Grunow) Peragallo;Stauroneis amphicephala Kützing,Stauroneis fluminopsis Van de Vijver & Lange-Bertalot,Stauroneis gracilior Reichardt,Stauroneis leguminiformis Lange-Bertalot & Krammer,Stauroneis mediterranea Lange-Bertalot & Van de Vijver.The detail descriptions of the taxonomical and ecological features of each species are given in this paper.

Abstract:A new varietas of Euonymus,Euonymus sanguineus var.paedidus L.M.Wang,is reported.This new varietas is similar to Euonymus sanguineus Loes..However,it differs not only from E.sanguineus,but also from all other species in Euonymus with its unique strong stinking fishy-scent flowers.It is also different from E.sanguineus by its shorter petiole (usually<5 mm).

Abstract:Divinyl reductase (DVR) converts 8-vinyl groups on various chlorophyll intermediates to ethyl groups,which is indispensable for chlorophyll biosynthesis.In the past decades,five DVR activities have been detected in higher plants.Recently,the results suggested that recombinant DVR proteins of rice and maize could convert divinyl chlorophyll a,chlorophyllide a,protochlorophyllide a,Mg-protoporphyrin Ⅸ monmethyl ester and Mg-protoporphyrin Ⅸ into corresponding monovinyl compounds,respectively,which confirmed the five DVR activities.Moreover,the data suggested that a single DVR with broad substrate specificity encoded by one gene was responsible for reducing the 8-vinyl groups of various chlorophyll intermediates in higher plants,but DVR proteins from different species had quite different reductive activities on the same or on different substrates even though they are homologous.In addition,it was proposed the multibranched chlorophyll biosynthetic pathways resulting from a single DVR protein in higher plants.In this review,we briefly introduced the advances on divinyl intermediates and DVR activities in chlorophyll biosynthesis,cloning of DVR genes and enzymatic assays of recombinant DVR proteins,number of DVR enzymes and multibranched chlorophyll biosynthetic pathways in higher plants.Meanwhile,we also discussed some problems to be further probed.

Abstract:The processes of anther development and pollen formation are controlled by series of genes and some transcription factors.As one of the largest families of transcriptional factors in plant,MYB plays an important role in such regulation processes.In this paper,we reviewed the domestic and foreign studies on anther development and pollen formation regulated by MYB in angiosperms in recent years.The regulatory pathways of these MYB transcription factors have been summarized,including the advances in the development of tapetum,deposition and degradation of the callose in anther,transportation photosynthetic product to the flower,dehiscence of the anther and so on.Furthermore,the regulatory network of MYB in the processes above through controlling the target genes for tapetum development,assimilate distribution and phenylpropanoid metabolism have been discussed,especially focused on the transcriptional regulation related to pollen formation and anther dehiscence.