Abstract:A total of 1 679 bp genomic DNA of BnCYP78A8 was first cloned from Brassica napus using Genomic walking method and then the coding sequence was cloned using special primers.The genomic DNA sequence is 1 679 bp,containing one intron and two exons.The coding sequence is 1 605 bp，coding for 534 amino acids.Sequence alignment of amino acid showed that BnCYP78A8 shared high identity （88%) with AtCYP78A8 in Arabidopsis thaliana.Bioinformatics analysis indicated that BnCYP78A8 protein contain one cytochrome P450 cysteine heme-iron ligand signature and one transmembrane domain.The real-time PCR results demonstrated that BnCYP78A8 expressed in all indicated tissues of Brassica napus,and its expression in root was higher than that in other tissues,suggesting that BnCYP78A8 might be involved in root growth.

Abstract:In this study,with Yunnan local landrace rice ‘SB70’ and Jinghong erect type of purple O.rufipogon as materials,a pair of specific primers were synthesized according to DNA sequence of WRKY45 gene reported in GenBank and used in PCR amplification of the genomic DNA of the material.A specific DNA fragment about 1.3 kb was obtained after PCR and then sequenced,the deduced amino acid contain a typical conserved WRKYGQK of WRKY protein by Blast analysis.It was found that the similarity of the fragment with different cultivar WRKY45 gene in GenBank is above 85% although there were some differences of nucleotide.The WRKY45 gene was constructed into plant expression vector pCAMBIA1300 with 6-phosphomannose isomerase gene (PMI) as selection marker gene.After PCR confirmation,recombinant clone was transformed to callus of rice cultivar ‘Yunzijing 41’ via agrobacterium tumefaciens system and 24 transgenic plantlets were obtained.

Abstract:Phenylalanine ammonialyase（PAL，EC 4.3.1.24） is the key enzyme of general phenylpropanoid metabolic pathway.A PAL gene,designated as DcPAL1（GenBank accession number：FJ864719),was cloned from carnation (Dianthus caryophyllus cv.Master) stems.DcPAL1 has a length of 2 397 bp with an open reading frame of 2 121 bp encoding a protein of 706 amino acids.A typical sequence of PAL active region and other active sites can be found in the deduced protein.The molecule mass of DcPAL1 was 76.8 kD with estimated pI of 5.84.The expression vector pETDcPAL1 was constructed and expressed in Escherichia coli.The expressed DcPAL1 protein exists in the form of inclusion body.The purified protein was obtained by affinity chromatography using NiNTA chelating agarose column.

Abstract:The expressions of tsa-miR172a and tsa-miR398b in roots of Thellungiella halophila (T.salsuginea),which were screened via Solexa sequencing,were studied by stem-loop RT-PCR methodology.The results showed that tsa-miR172a was up-expressing and tsa-miR398b was down-expressing under the treatment of NaCl (300 mmol·L^-1,72 h).With the stem-loop RT-PCR,tsa-miR172a and tsa-miR398b were amplified and the optical densities of electrophores were analyzed specifically.The ratios of NaCl stress to control were 1.8 and 0.55,which were roughly consistent with the results 2.00 and 0.44 obtained by Solexa.Our study established an effective stem-loop RT-PCR system:three primers,namely miRNA stem-loop primer,miRNA forward primer and miRNA universal reverse primer,were designed for each miRNA.The reactions were incubated at 94℃ for 2 min,followed by 23 cycles of 94℃ for 15 s and 55℃ for 45 s.The stem-loop RT-PCR system to identify miRNAs in Thellungiella was discussed.

Abstract:A differentially expressed gene fragment was isolated from TuMV-infected seedling leaves of non-heading Chinese cabbage (Brassica campestris ssp.chinensis Makino) through cDNA-AFLP technique.The full-length cDNA of this gene,named BcLRK01,is 2 124 bp in size and encodes a leucine-rich repeat receptor-like kinase with 707 amino acids.Real time PCR was performed to detect its expression patterns under TuMV infection and the inductions of high salinity,cold,salicylic acid (SA),jasmonate acid (JA) and ethylene (ET). The results showed that all the treatments induced the expression of this gene significantly in different extents,which indicate that it may be a pathogenesis-related gene of virus disease in non-heading Chinese cabbage and involves in the signaling pathways of high salinity,cold,SA,JA and ET.

Abstract:Two previously identified strong coldtolerant introgression lines of IL5243 and IL5335 from Dongxiang wild rice (Oryza rufipogon Griff.) were used to investigate the meiosis behavior,chromosome recombination and the molecular evidence of alien genes introgression.The results showed that the rate of pollen mother cells (PMC) with normal meiotic behavior in the IL5243 and IL5335 was to 89.93% and 90.22%,respectively.And they finally formed the normal mature pollen;The rates of pollen germination in vitro were (83.03±2.82)% and (81.96±1.73)%,respectively.There were no significant differences between the coldtolerant introgression lines and their parents.However,at meiosis I,the low frequency of abnormal chromosome behavior was observed in IL5243 and IL5335,such as univalent,8shape bivalent,multivalent and some PMCs (3.95%~5.15%) exist lagging chromosomes at anaphase I and so on,which suggested that there were genetic exchange and recombination between cultivated rice and common wild rice.In addition,the high frequency of double nucleoli was observed at pachytene in the two cold tolerance introgression lines (IL5335 and IL5243 were 38.9% and 27.0%,respectively),while their parents only had one nucleolus.Through SSR markers and structure analysis,we further confirmed that introgression of some Dongxiang wild rice DNA fragments in the strong cold resistance introgression lines through chromosome exchange and recombination between the cultivated rice and the wild rice.These results laid a foundation for further excavating and using this rice coldtolerant gene in the future.

Abstract:Ipomoea batatas cv.Xushu 18 and its two wild relatives I.hederacea Jacq.from American and Hong Kong in China were studied by DAPI banding and rDNAfluorescence in situ hybridization.The DAPI banding showed the karyotype of Ipomoea batatas and I.hederacea Jacq.from American and Hong Kong in China are 2n=6x=90=72m+18sm(18SAT) with satellites on chromosome 1,3 and 6;2n=2x=30=30m(4SAT);2n=2x=30=20m+10sm(4SAT),both with satellite on chromosome 6 and 12,respectively.The FISH data indicated that three pairs of 5S rDNA signals,located on centromere,pericentromere and the telomere of chromosome respectively of Ipomoea batatas;Two pairs of 45S rDNA signals,located on chromosome 6 and 12 were detected on both I.hederacea Jacq.;While 1 pairs of 5S rDNA signals presented on chromosome 6 of I.hederacea Jacq.from Hong Kong,2 pairs of 5S rDNA signals occurred on the chromosome 6 and 12 of that from American.Taking all the data obtained in the study,both I.hederacea Jacq.were distant from the sweet potato,and there were some differentiations in the chromosomes of the I.hederacea Jacq.from different territories.

Abstract:SRAP molecular markers were used to study the genetic diversity on population and individual levels of 79 Cibotium barometz which were from 7 populations.The results showed that:10 SRAP primer combination amplified 107 bands with 91 (85.98%) polymorphic.Nei’s gene diversity index of SRAP was 0.229 6.Shannon’s information index was 0.358 6.That implied that there was high genetic diversity among the popolations.The total genetic diversity was 0.229 6.The genetic diversity within population and the coefficient of gene differentiation were 0.135 4 and 0.410 6,respectively.That implied that it was 41.06% of genetic diversity among populations，and was 58.94% of genetic diversity within populations.Gene flow among population was 0.717 8 which implied that the gene flow was at a low level.The genetic similarity coefficient and the UPGMA dendrogram indicated that populations with similar conditions were clustered firstly,the geographical distribution was not distinctive.

Abstract:The genetic diversity of 16 Paeonia rockii lines in one population was analyzed by using inter-simple sequence repeat markers (ISSR).Fifteen primers selected from 100 primers were used for ISSR amplification.A total of 134 bands were generated,of which 96 bands were polymorphic bands (the percentage of polymorphic band,PPB=71.6%).According to the results of ISSR amplification,which were analyzed to Jaccard similarity coefficient by NTSYSpc 2.10e software,the genetic similarity coefficient varied from 0.45 to 0.93.The clustering dendrogram was constructed by UPGMA method.Sixteen P.rockii materials were divided into four major groups while the similarity coefficient was 0.534.Class Ⅰ included six of P.rockii materials,and five in six was crown form,left a single form species.But other classes also have crown flower varieties.Class Ⅱ had an anemone form species,it was the only anemone species elected in the selected materials.Four different color and form materials were clustered into Class Ⅲ,suggest that the character of closer phylogenetic relationship species were varieties.A group of Class Ⅳ included four white flowers materials,whose form were different.Group B was P.rockii ‘Yinxiannv’ alone ,it was the only red material selected.Thus,genetic clustering classification of different resemble coefficients was not consisted with that based on the flower color and form.

Abstract:In this paper,the structure of the root tubers of Ophiopogon japonicus and Liriope spicata at different developmental stages was observed under light microscope by means of the method of paraffin section.The results indicated that root tubers enlargement of O.japonicus and L.spicata was all initiated from the apical part of adventitious root and that both the cell layer number and cell size in cortex changed dramatically during development in both species,which finally enlarged the root tubers.But we found that the cell layer number increasing in L.spicata contributed more than cell size change to the root tuber enlargement,while in O.japoriicus both cell layer number and cell size contribute equally to the root tuber development.

Abstract:Northeast mung bean (Phaseolus radiatus) as materials were used to study development characteristics of border cells by suspended culture with agar pour plate.The results showed that bean border cells were spherical shape with early development,and develop into oval shape,long oval shape and strip shape with growth gradually.The root border cells have high viability in development process and the viability were at 70%~80% and tended to be stable when the root length was greater than 10 mm;The number of root border cells reached maximum (about 13 000)when the root length was 25~30 mm;Pectin methylesterase activity of root cap reached the highest value（1.486 H⁺μmol·root cap^-1·h^-1） with 5 mm root length,then changed in 1.107~1.256 H⁺μmol·root cap^-1·h^-1 and tended to be stable with the root elongation.

Abstract:The leaf epidermis of Triadica rotundifolia (Hemsley) Esser-endemic plants in limestone region,and of Triadica sebifera,Triadica cochinchinensis were examined through scanning electron microscope (SEM) and light microscope (LM).By comparing the three species,we analyse T.rotundifolia’s environmental adaptive mechanisms based on its leaf epidermic morphological characteristics.The results showed that:abaxial cells of T.rotundifolia were small size reversely,with irregular type and closly arranged.The stomatas could only be seen on abaxial epidermis.The stomatal density and index of T.rotundifolia were lower than that of other two species.Stomatal type was anomocytic without subsidisry cells.Horny layer and wax layer thickly covered on the epidermism,with its waxy coat lamellar and reticulation.All of these implied that T.rotundifolia can adapt to limestone habitats condition.

Abstract:With four-year-old outer petals of Yulania×soulangeana on different flowering stages as materials,floral color index,anthocyanin,flavonoid,soluble sugar content,pH index and relative enzymes were studied to explain the chromogenic mechanism of floral color in Yulania×soulangeana.The results showed that:(1)As the flowering stage progresses,PAL and CHI activity become lower,pH index of petals are higher,and the contents of soluble sugar,anthocyanin and flavonoid become lower.The light of the petal strengthened,the red chroma,multi-colored chroma decreased.And every parameter in different flowering stages had significant difference.(2)With correlation analysis the variation of soluble sugar content,PAL and CHI activity and anthocyanin and flavonoid contents showed significantly positive correlation.The variation of pH index,the lightness L^*-value and anthocyanin and flavonoid contents showed significantly negative correlation.The chromatic component a^*-value and anthocyanin contents showed significantly positive correlation.In conclusion,the contents of anthocyanin and flavonoid can affect the floral color of Magnolia×soulangeana.The petals of different color need soluble sugar content,PAL and CHI,pH index to complete normally physiological metabolism that regulate anthocyanin forming,and change petal color of Yulania×soulangeana.

Abstract:Aroma components in ‘Jinba’ in different florescence and inflorescence parts were analyzed by Head Solid -phase Micro-extraction and GC/MS technology.The basic structure of the petal cell and the cross-section was observed by the biological microscope.The results showed that:(1)There were 24 components identified at bud stage,31 at early opening stage,43 at full opening stage and 22 at declining period.With the flower blooming and senescence,the contents of ketones,terpenes and alcohols raised to the highest at full opening stage,and the contents of alkanes,aldehydes and heterocycles decreased.(2)At full opening stage,there were 31 components identified in the ligulate flower and 50 in the tubular flower.The ligulate flower was probably the most important part that could influence the volatile releasing.The categories of the main aromatic components of ligulate flower in different parts were not change,but their contents were decreased from inner part to outer part.(3)Isocyclocitral,eucalyptol,α-pinene,β-farnesene,and caryophyllene were the characteristic constituents of aroma.(4)The results of microscopic observation showed that aroma was probably emitted from the intercellular space and the adaxial epidermis was the main releasing part.

Abstract:The effects of different shading treatments (100%,65%,45% and 15% of full sunlight) on the photosynthetic characteristics were examined with five cultivars of Paeonia suffruticosa during the period from 2008 to 2011.The results indicated that the light-saturation point (LSP) and the light-compensation point (LCP) of the five cultivars of P.suffruticosa under the full sunlight were quite high.LSPs were about 1 000 μmol·m^-2·s^-1 and LCPs were 73～100 μmol·m^-2·s^-1.With the sunlight intensity reducing,the LSPs and LCPs of all cultivars decreased gradually.The net photosynthetic rates (P_n) under 65% sunlight were significantly higher than those under full sunlight.Under 45% sunlight the P_n of ‘Aoyang’ and ‘Zhuguangmorun’ were significantly higher than those under full sunlight，while the P_n of other three cultivars had no remarkable change.The P_n of all the cultivars under 15% sunlight were significantly lower than those under full sunlight.The flowering rates of all the cultivars were quite high under 65% and 45% sunlight and there were no difference with those under full sunlight.But under 15% sunlight they were significantly lower than those under full sunlight.The flower diameters of all the cultivars under 65% sunlight were increased and those under 15% sunlight were decreased significantly.Under 45% sunlight the flower diameters were increased at different levels except ‘Aoyang’.The effects of different shading treatments on the flower color were related to the sunlight intensity and the color of the flower itself.The color of all the cultivars had no remarkable change under 65% sunlight and they even got improved for ‘Fenzhongguan’ and ‘Yingrihong’,but they both gradually become lighter under 45% and 15% sunlight.With the same trend the color of ‘Zhuguangmorun’ became gradually lighter and blue.The color of ‘Aoyang’ under 45% had no change with those under full sunlight,but become lighter under 15% sunlight.For ‘Lanbaoshi’ it had no remarkably change under different shading treatments.It is indicated that P.suffruticosa is a sun plant with shade tolerance.Moderate shading can improve its photosynthesis and the flower quality but strong shading makes them worse.

Abstract:We studied on the drought tolerance of four different energy willow clones (Salix dasyclados,S.mesu,S.fragilis,S.viminalis).Using potted 1-year old seedlings of the four different clones,we conducted a soil-drought controlled experiment and measured the changes of SOD activity,POD activity,CAT activity,MDA content,protein content and relative growth of height.The results revealed the following consequences.(1)With the decrease of soil water content,the protective enzyme activities of 4 energy willow clones improved until the soil water content was below the level of 11.4%.This phenomenon showed that SOD,CAT and POD acted synergistically on assuring the plants’ regular growth.While the water content fall below 11.4%,both S.dasyclados and S.mesu CAT and POD activities significantly reduced.It indicated that under this water condition the seedlings suffer from the drought stress.(2)The MDA contents of all the four clones increased along with the drought stress enhancing.The growth was remarkable when the water content fall to 11.4%.The change of S.mesu is especially notable.(3)The content of protein was increasing as the soil becoming more and more arid.But it turned to decrease as the water content was fewer than 8.1%.(4)The relative growth of height of all the energy willow clones reduced while the drought condition increased;(5)According to fuzzy synthetic evaluation of the activities of three protective enzymes,MDA content and protein content to water stress in leaves,the drought-tolerance of the four energy willow clones decreased in the following order:S.fragilis>S.viminalis>S.dasyclados>S.mesu.

Abstract:Effects of exogenous abscisic acid (ABA) on the growth and some physio-biochemical signs in wheat (Triticum aestivum L.) seedlings under cadmium stress (100 mg/L) were studied with hydroponics.The results showed that:(1)The malondialdehyde (MDA) content in wheat seedlings was significantly increased (P<0.05),and the growth of wheat seedlings was also obviously inhibited by Cd²⁺ stress.(2)Exogenous ABA with the concentration of 5.0 μmol/L playing a noticeable role increased root activity and proline content,enhanced activities of SOD,POD and CAT,and decreased MDA content.(3)Exogenous 1.0~5.0 μmol/L ABA eased the negative effects of Cd²⁺ on the growth of wheat seedlings,and 5.0 μmol/L ABA worked best with shoot height,root length and total biomass of seedlings in 5.0 μmol/L ABA and Cd²⁺ stress had increased 6.73%,149% and 10.52%,respectively,compared with those under single Cd²⁺ stress.However,10.0 μmol/L ABA exacerbated the growth of wheat seedlings.On the whole,preference concentration of exogenous ABA could ease the inhibitory effects of Cd²⁺ stress on the growth of wheat seedlings and boost the tolerance of wheat seedlings to Cd²⁺ stress by increasing SOD,POD and CAT activities and proline content.Furthermore,the most suitable concentration of ABA was defined to be 5.0 μmol/L.

Abstract:In order to explore adaptive capacity of Oligostachyum lubricum to different soil water content,we investigated changes of physiological activity in leaves such as ion leakage,MDA content,chlorophyll content,Chl a/Chl b,Chl/Car,SOD activity,POD activity,proline content and soluble protein content in 58-day-experiment.2-year-old O.lubricum seedlings were potted with different soil moisture contents:<30%(T₁),40%～50%(T₂),60%～70%(T₃),80%～90%(T₄) of field capacity and root flooding(T₅),which were controlled by measuring pot soil water content and watering every day.The result showed that:(1)Ion leakage,MDA content,Chl a/Chl b,SOD activity,POD activity,proline content and soluble protein content increased significantly while chlorophyll content carotenoid content and Chl/Car decreased significantly in treatment T₁ with the increase of treated time.(2)The physiological characteristics except carotenoid content and proline content started to change after treated 14 days in treatment T₅ in ways that was the same as treatment T₁.All leaves became dry and fell off after treated 14 days by T₁ and 28 days by T₅.(3)All physiological characteristics in treatment T₂,T₃ and T₄ finally stabled at the level before treatment after changing for some days.The results indicated that O.lubricum injured seriously and even die in soil with less than 30% relative moisture content and grew well in soil with 40%～90% relative moisture content.O.lubricum could live for 28 days when root were flooded and would die if root were flooded for more than 28 days.

Abstract:The drought resistant capability of 8 common garden ground cover plants in south China were studied based on the water-controlled pot experiment.The effect of drought stress on permanent wilting rate,foliage water-losing rate,relative water content,electric conductivity,soluble sugar,proline and malondialdehyde (MDA) of those plants were measured.Results showed that:(1)The plant having the lower permanent wilting rate and the higher foliage water-losing rate had the stronger drought-resistant capability,such as Schefflera arboricola and Syngonium podophyllum.(2)With drought stress going on,the relative water content of these plants decreased obviously.But the relative electric conductivity and MDA content increased at the different degree.The content of soluble sugar and proline had different tendencies.(3)Based on the comprehensive analysis with subordinate function,the drought resistant capability of woody and herbaceous plants were ranked as:Schefflera arboricola (Hayata) Merr.>Ixora coccinea L.>Excoecaria cochinchinensis Lour..Hymenocallis americana (Mill.) Roem.>Tradescantia spathacea Sw ‘Compacta’>Syngonium podophyllum Schott.‘White Butterfly’>Zephyranthes candida (Lindl.) Herb.>Alternanthera dentata (Moench) Stuchlik ‘Ruliginosa’.According to the comprehensive analysis of the drought resistance of these plants,it was indicated that the effective indexes that could reflect the drought resistance of garden ground cover plants were:the permanent wilting rate,foliage water-losing rate,relative water content,electric conductivity and MDA.

Abstract:By the methods of spraying leaves and root drench with paclobutrazol (PP₃₃₃),chlorcholinchlorid (CCC) or mepiquat chlorride (DPC) in different concentrations,through the test of the morphological indices(plant height,inernod length,leaf length and width,length of flower shoot,pedicel length,flower diameter and flowering date) and the physiological indices (chlorophyll content,photosynthesis rate,transpiration rate,enzymatic activity and the sugar soluble content in potted rose leaves),study the effects of PP₃₃₃,CCC and DPC on the growth and development of the potted rose (‘Shijizhichun’).The results showed that：Firstly,it had the different influence to the morphological and physiological indices of potted rose,using retardants with different concentrations and ways.Under the treatments with appropriate concentrations and ways,the plant height could be decreased through shortening inernod length,the plantype was compact,the plants blossom normally.Therefore,the plant value of view was increased.At the same time,they also could increase plant chlorophyll content,improve the photosynthetic efficiency and increase SOD,POD activities and the sugar soluble content in plant leaves.It had a significant effect on the ornamental quality of potted rose.Secondly,the treatments by spraying leaves with 700 mg·kg^-1 PP₃₃₃ and by drenching the roots 300 mg·kg^-1 PP₃₃₃ obtained the best results.By spraying leaves with 1 200 mg·kg^-1 CCC and 300 mg·kg^-1 DPC got better results.They could decrease the plant height and improve the plant value of view.

Abstract:By taking six provenance seeds of species Chukrasia tabularis A.Juss as the test material and through simulating drought stress with different concentrations and osmotic potential of polyethylene glycol (PEG-6000),the effects of drought stress on germination rate,germinating potential,radicals,hypocotyls length,germination index,viability index and ratio of root to shoot were investigated.The results showed that:(1)PEG retarded the proceeding of seeds germination of C.tabularis and the germination percentage,germination index and seed viability index were all showed the downtrend obviously with increasing concentration of water stress;The seeds treated with -0.86 MPa water potential of PEG did not germinate at all after the experiment finished.So this indicated -0.86 MPa water potential was the threshold for the germination of C.tabularis seeds.(2)When the water stress above -0.40 MPa,C.tabularis seedling radicale length was no significant difference and even longer than that of control group.The findings revealed that the water potential higher than -0.40 MPa was beneficial to the growth of the radicals of C.tabularis seeds;the growth of C.tabularis seedlings decreased with arising PEG concentrations.(3)The ratio of root to shoot as an important indicator of sound seedling,appropriate water stress could increase the ratio of root to shoot.When the water stress higher than -0.20 MPa,the ratio of root to shoot of all kinds provenance have reached the maximum.In Summary,C.tabularis seed can germinate under appropriate drought stress.The seeds from Khin Aye Pale and Phu Wiang is better than that from Sanya and Ulu Tranan.

Abstract:Allelopathy of 0(control treatment),0.1,0.2 and 0.5 g/mL methanol extracts and aqueous extracts of rhizosphere soil from Stipa bungeana were studied using the seeds of S.bungeana,its dominant species Stipa grandis and Thymus mongolicus as receivers and by laboratory bioassay methods.Compared with the control,the results showed that:(1)Methanol extracts inhibited the germination of S.bungeana,Stipa grandis.Aqueous extracts stimulated the germination of S.bungeana,and it stimulated the germination of T.mongolicus partialy,but inhibited that of S.grandis.(2)Methanol extracts had different effects on different receivers,it barely affected the growth of root and shoot of S.bungeana and S.grandis,but inhibited the growth of T.mongolicus significantly.Aqueous extracts could not stimulate the root growth of S.bungeana,the same to the root and shoot growth of the other receivers,but had significant stimulation to the shoot growth of S.bungeana.(3)Methanol extracts inhibited the growth of T.mongolicus and S.grandis,it stimulated the growth of S.bungeana except the concentration of 0.2 g/mL.Aqueous extracts stimulated the growth of S.bungeana and T.mongolicus,but inhibited that of S.grandis.Therefore,methanol extracts and aqueous extracts of rhizosphere soil from S.bungeana are different,and they have different effects on different receivers.one receiver has different reaction to different extracts.

Abstract:During the restoration of plant cover in the degraded cropland,the existence of early successional dominant species was one of the most important factors influencing the process of vegetation succession.This experiment including two treatments:(1)natural regeneration (CT),and (2) sweetclover (Melilotus officinalis L.) planted at a density of 11.3 kg·hm^-2 (LT),was designed to explore the dynamic of plant community in the initial vegetation succession by introducing biennial legume species into the abandoned cropland located in the semiarid Loess Plateau of China.After 6-year-experiment,the results indicated that LT helped increase vegetation cover and accelerate the course of vegetation succession.For example,some later successional species like Artemisia frigida,Heteropappus altaicus and Stipa breviflora were showing up in LT in the third year of vegetation succession.Moreover,LT was beneficial to improve the productivity and stability of plant community.In contrast to CT,the averaged aboveground biomass of LT was higher by 67.90% across the experiment.Besides,LT helped increase the soil total nitrogen in the early stage of vegetation restoration.Compared with CT,the average soil total nitrogen in 2003～2005 was higher by 7.32% in LT.Across the experiment,the soil total nitrogen and available phosphorus were the limited factors influencing the plant community in both CT and LT.Therefore,the introduction of biennial legume specie is a better way to restore the plant community in the semiarid Loess Plateau,and the addition of phosphorus fertilizer during succession of plant community is also recommended.

Abstract:In order to investigate the impacts of nitrogen (N) deposition on species diversity and community composition of herbaceous vegetation in desert steppe,we conducted a simulative N deposition experiment at ambient environment by adding N fertilizer into the plots in Shapotou area,northern China.We set four levels of N addition,0,6,12 and 24 g·m^-2,the different levels of N were singly added in the first year and then none for the following two years.The results indicated that both plant species diversity and community abundance decreased with the increase of N addition levels at a given year,especially,community abundance showed the greatest decline compared to the species diversity.The interannual variations of both species diversity and community abundance showed a similar phenomenon that the difference among the levels of N addition was significant under the low levels of N addition,but nor for the high levels of N addition.N deposition changed plant community composition of herbaceous vegetation layer in desert steppe,and the perennial forbs were more sensitive to be lost under N enrichment in contrast to perennial grasses,and finally the transformed community was dominated by fewer dominate species.It can be concluded that N deposition would reduce species diversity,change community composition of herbaceous vegetation,and the impacts of N deposition on desert ecosystems would not be eliminated immediately when N enrichment ceased.

Abstract:An experiment was conducted by the methods of path analysis and competition index based on biomass,to study the impact of different planting density of Catalpa ovata seedling above-ground and below-ground competition to general competition.The result showed that there were close relationship among above-ground biomass,below-ground biomass and total biomass,with the density increased the biomass of root,shoot and leaves decreased and the ratio value of above-ground biomass with below-ground biomass was lower than 1.Above-ground competition was obviously larger than below-ground competition under the same density.The direct effect of above-ground competition on general-competition was from 0.449 3 to 0.973 1,which was obviously larger than below-ground competition on general-competition (0.275 6~0.773 2).Shoot and leaves of C.ovata seedling competition play an important role in general-competition.

Abstract:It was investigated the algae in the Gongbu Nature Reserve,Tibet.The results showed that 189 species (including varieties) were found.Bacillariophyta has most species,with 109 species of 18 genera in 9 families.Chlorophyta was the subdominant division,with 50 species of 20 genera in 9 families.Cyanophyta was ranked as the third dominant division,with 28 species of 10 genera in 8 families.They were belonging to 5 divisions,28 families,and 50 genera.Bacillariophyta and Chlorophyta dominated in species.Rhodophyta and Chrysophyta had the least species,with just only 1 species,which belonged to 1 family and 1 genus,respectively.There were 7 types of algal community in the Gongbu Nature Reserve,namely Oscillatoria community,Rivularia community,Nostoc community,Hydrurus foetidus community,Cymbella community,Ulothrix community,and Zygnema-Mougeotia-Spirogyna community.Water quality was evaluated by indicator algae analysis.It represented that the overall water quality was good,and the water had not been polluted seriously.Most of the waterbodies were β-mesosaprobic zones,and the others were oligosaprobic zones.The floristic characteristics in the Gongbu Nature Reserve are typical plateau cold water streams with fast flow.The species which represented the source of mountain stream could be observed obviously,and pollution-resistant algae were rarely found.This study could provide suggestion for water and algae diversity protection in this area.

Abstract:Fagopyrum densovillosum J.L.Liu var.pterocarpum J.L.Liu et X.J.Li,a new variety of the Polygonaceae from Sichuan,China,is described and illustrated.It is different to Fagopyrum densovillosum J.L.Liu by its major achenes,2.5～3 mm long and (2～) 2.5～3 mm in diameter,winged on the angular,wings 0.5～1 mm wide,stamens longer than pistils.In addition,the new variety is also different to Fagopyrum gracilipes (Hemsl.) Damm.et Diels var.odontopterum (Gross) Sam by its densely pubescent or villose plants,thicker and red-brown stems and branches,dense nodes,rugulose and small pustulate leaf blade on the surface,stamens longer than pistils.

Abstract:Emmenopterys henryi,was considered as a company species of deciduous broadleaved forest,evergreen or mixed forest in subtropics middle or lower mountain area.We witnessed wild stocks of Emmenopterys henryi in Shaanxi Zhouzhi County,north slope of Qinling Mountain during 2010 to 2011 survey of plant resourse,which expanded its latitudinal natural range north-foward about 0.5°,considered north slope of Qinling Mountain belong to warm temperate zone.

Abstract:The species Habenaria fargesii is reported as a new record of Shaanxi,China.

Abstract:To obtain suitable protocol for proteome of cucumber suspension cultured cells,we optimized the pH gradient of IPG strip,the method of protein extraction,reagent and concentration of lysis buffer and SDS-PAGE condition.Results showed pH 4~7 IPG strips,the extraction method acetone precipitation after lysis,lysis buffer containing 8 mol/L urea,2 mol/L thiourea,2% IPG Buffer,4% CHAPS,1% TBP,65 mmol/L DTT,2 mmol/L EDTA,0.001% bromophenol blue and 1% cocktail and 11% gel concentration were appropriate for the sample preparation of cucumber suspension cultured cells.

Abstract:To seek a standardizing program of ISSR technique for genetic diversity analysis of Thespesia populnea,a single factor experiment was designed to optimize ISSR-PCR amplification system.The suitable reaction system was obtained,that is 20 μL reaction system containing 2.0 μL of 10×Buffer,27.5 ng of total DNA,2.0 μL of dNTP ,1 U Pyrobest DNA polymerase and 1.25 μmol/L of ISSR primer.The profile of ISSR-PCR was an initial denaturation step for 5 min at 94℃,follow by 35 cycles of 1 min at 94℃,45 s at annealing temperature 49℃,1 min at 72℃,and a final elongation 10 min at 72℃ for one cycle,then termination reaction at 4℃.Ten polymorphic primers were screened using this reaction system.Stable and clear amplification patterns were obtained,indicating the ISSR-PCR amplification system was feasible.The factors affecting the amplification of genome DNA of Thespesia populnea were also discussed in the paper.It provides the basis on studies of germplasm resources and genetic diversity of T.populnea.

Abstract:Physiology regulatory function of NO in plants has been intensively studied since 1992.It has been showed that NO not only plays important role in plant disease resistance,but participates in plant growth,development and abiotic stress tolerance.This review focuses on the function of NO in plant growth,development,abiotic stress tolerance and its ‘cross-talk’ with plant hormones.

Abstract:14-3-3 proteins are considered master regulators of many signal transduction cascades in eukaryotes.They can interact with target proteins containing phosphoserine or phosphothreonine to regulate the activities of various enzymes which relate to carbon and nitrogen metabolism,tricarboxylic acid (TCA) cycle,the shikimate pathway and so on.Based on the recent research status on protein discovery,gene identification,structure and function of 14-3-3 proteins in plant are summarized in this paper.Meanwhile,the mechanism of 14-3-3 proteins to interact with the target is described.Furthermore,we bring forward the prospect about the further study on plant 14-3-3 proteins.

Abstract:Cold stress is a major abiotic stress factor during plant growth and it is also one of the main factors affecting the production of crop.In recent years,studies on cold tolerance of plants have shown that there is a complex signal network responding to low temperature stress in plant.Many related genes were reported in this genetic regulatory network system.Not only plant hormones are involved in the response,but also the gene transcription,even the posttranscriptional gene regulation.In this paper,recent advances on cold-resistant gene are regulated of plants are highlighted.