Abstract:In order to construct prokaryotic expression vector and to study the recombinant gene expression in the host bacteria,we cloned complete gene of Triticum aestivum FeSOD ORF by the RT-PCR method followed by restriction enzymes cutting and connection.The induced time,IPTG concentration and temperature of prokaryotic expression were optimized using SDS-PAGE.The results showed that the full-length cDNA sequence of T.aestivum FeSOD ORF(600 bp) was cloned,then a recombinant of prokaryotic expression vector pET-SOD was constructed successfully.FeSOD protein in inclusion body can express effectively after the expression vector pET-FeSOD was transformed to Rosetta (DE3).The SDS-PAGE results indicated that pET-FeSOD fusion protein was expressed with molecular weight of 25.8 kD,with the pET-Duet1’s own induction produced 3.0 kD protein.The result is consistent with the 22.8 kD protein which encoded by FeSOD gene.The optimal expression condition was set as 0.5 mmol/L IPTG,induced temperature 37 ℃,and induced time 5 hours.These results are expected to lay a foundation for further studies on the properties and function of this gene.

Abstract:The miR390-targeted TAS3 gene named FaTAS3 was isolated from strawberry (Fragaria ananassa ‘Allstar’) with the methods of PCR and RACE.Sequence analysis showed that the cDNA was consisted of a 742 base pair with a 16 bp poly A and highly conserved domains,two ta-siRNA-generating regions and one miR390 complementary site.The full-length DNA of FaTAS3 is 824 bp with an intron sequence of 98 bp at the 130 bp from the 5′ end of TAS3 transcript.In addition to the TATA/CAAT-box,its promoter predicted by bioinformatic analyses also contained some specific regulatory elements such as G-box,C-box and etc.The results of real time RT-PCR showed that the expression pattern of miR390 and its targeted TAS3 gene in strawberry is a similar manner to Arabidopsis.So we deduce that the biological formation of strawberry TAS3 gene was also cleaved by miR390.

Abstract:Genetic relationship and diversity of 22 papaya (Carica papaya L.) major cultivars in China were analyzed based on sequence-related amplified polymorphism (SRAP).(1)The 20 pairs of SRAP primers generated a total of 249 fragments,and polymorphic bands were 110 which accounted for 43.20% in the total amplified fragments.The number of amplified and polymorphic fragments was 12.45 and 5.50 per primer pair,respectively.(2)The polymorphism information content (PIC) values of these markers varied from 0.15 to 0.79,averaging 0.49.(3)UPGMA cluster analysis and principal coordinates analysis (PCOA) showed that the range of genetic similarity (GS) was 0.72~0.96 among 22 papaya cultivars with a low genetic diversity.All cultivars could be divided into three groups at the GS of 0.87.These results indicated that SRAP analysis could be used to reveal effectively the genetic relationships of papaya cultivars in China,providing a scientific basis for the classification,protection and effective utilization of these resources and breeding new varieties.

Abstract:In search of a new method to illustrate the microsporogenesis,indirect immunofluorescence microscopy with DAPI (4′,6-diamidino-2-phenylindole) staining was conducted to observe the microtubule cytoskeleton pattern and chromosomes behavior during microsporogenesis of Populus euphratica.The results showed that:(1)Meiotic chromosome behavior is normal during microsporogenesis,with univalent at diplotene and lagging chromosome at metaphase Ⅰ and the varied number of nucleoli.(2)Microtubule cytoskeleton was involved in many key processes of microsporogenesis.Spindles of metaphase Ⅱ were mutually parallel or tripolar.No typically phragmoplasts were observed at telophase Ⅱ,while simultaneous-type cytokinesis show an inward-oriented infurrowing of the callosic parental wall to partition the meiotic cytoplasm,mediated by the radial microtubules systems.The tetrad was shaped in a tetrahedral or isobilateral pattern.(3)Abnormal meiosis were also observed during microsporogenesis,such as fused spindles at metaphase Ⅱ,asynchronous division of the second meiosis,furrow occurred between the mutually parallels at the second division,as well as triad and dyad were found together with tetrad at tetrad stage,which led to formation of natural 2n pollen and stuck pollen.

Abstract:In the study,Conyza bonariensis that collected from natural agricultural plant communities is taken as the donor,and typical dicotyledonous Vicia faba and typical monocotyledonous Zea mays seedlings as receptors.Micronucleus test and chromosome aberration test are used to investigate the genetic toxicity of aqueous extracts of different organs of C.bonariensis on the receptors.The results show that:(1)In the aqueous extracts of C.bonariensis,both root tip cells of V.faba and Z.mays in each phase of mitosis are significantly affected,which appear micronucleus,chromosome bridge,chromosome fragments,chromosome rings,lagging chromosomes,chromosome adhesions and other chromosomal aberrations;(2)The division inhibition effect of aqueous extracts from different organs of C.bonariensis on seedling root tip cells of V.faba is significantly greater than that of Z.mays;(3)Chromosome aberrations of V.faba and Z.mays root tips induced by aqueous extracts of C.bonariensis present a significant concentration-dependent effect:the higher the concentration of the aqueous extracts,the higher the receptor micronucleus rate and distortion rate,and the lower the corresponding mitotic index,which show that the mutagenic effects of the aqueous extracts and concentration is positive correlation,but not a simple additive effect;(4)All the aqueous extracts from C.bonariensis have strong genetic toxicity,however,the whole performance of the allelopathic effects from the organs is leaf>fruitlet>stem>root.We suppose that the reason C.bonariensis successfully invade new habitats is that its secreted allelochemicals impact on mitosis and cell morphology of the growing point of receptors,resulting in a variety of chromosome aberrations and irreversible genetic damage.

Abstract:Morphological and anatomical features were observed during the formation of adventitious roots of Populus tremula×P.tremuloides by micro-cuttage multiplication with paraffin method,and the relationship between root primordia site and rooting was also analyzed.The results showed that ontogeny process of adventitious roots can be divided into four stages.The stage of adventitious root primordium induction:the cells of vascular cambium divided into parenchyma cell groups which contained the characteristics of meristem.The stage of adventitious root origination:the vascular cambium cell kept dividing and form adventitious root primordium initial cells which showed strong mitogenic ability.The stage of adventitious root expression:the adventitious root primordium initial cells kept dividing and formed root primordium with directivity.The stage of adventitious root elongation growth:the root primordium stretched out from lenticel and nick,inner vascular system well matured,then the adventitious root formed.The study showed that Populus tremula×P.tremuloides was bark inductive root formation type,adventitious root primordia originated in the vascular cambium area,single site of origin,was hard rooting type.

Abstract:The original bulbs of Dendrobium officinale were soaked in the mixture of different mass concentration colchicine (C₂₂H₂₅O₆) and 0.02 g·mL^-1 dimethyl sulphoxide (DMSO).The variant plants were identified in morphology,cytology,in order to obtain steady tetraploid plants and analyze its physiological characteristics.Results showed that:with 2.0 g·L^-1 colchicine and 0.02 g·mL^-1 DMSO mixed aqueous solution to deal with the original bulb for 36 hours,the plant induced rate could reach 20%.Copmared with diploid plants,the tetraploid plants became dwarf;its stems were thick and short;leaves were small and thick;stomata diameter were increased.The chromosome numbers of diploid cells was 2n=2x=38,while tetraploid cells was 2n=4x=76.With flow cytometry,the relative DNA content of tetraploid was 400,diploid was only 200.Tetraploid plants leaf chlorophyll,soluble protein,soluble sugar contents were higher than that of diploid,were 5.03,3.59,2.98 mg·g^-1,respectively;The main antioxidant enzyme POD and SOD activities in the leaves were significantly higher than that of diploid,were 9.08 and 180.4 U·mg^-1,and the tetraploid plants significantly reduced the accumulation of MDA content.This research show that:2.0 g·L^-1 colchicine and 0.02 g·mL^-1 mixed aqueous solution to deal with the original bulb lasting 36 hours can improve the success rate of induction,to reduce the proportion of chimeras.So,this combination is the best conditions.

Abstract:The Chromosome numbers and karyotypes of six species of Saussurea DC.in the Hengduan Mountains were analyzed with technology of the conventional squashing slides.The karyotype formulas and types were as follow:S.polycolea var.acutisquama,2n=2x=32=20m+12sm,karyotype belonged to stebbins 2B type;S.globosa,2n=2x=34=16m+18sm,karyotype belonged to stebbins 2B type;S.katochaete,2n=2x=32=8m+18sm+6st,karyotype belonged to stebbins 3B type;S.columnaris,2n=2x=32=24m+8sm,karyotype belonged to stebbins 2B type;S.graminea,2n=2x=28=8m+18sm+2st,karyotype belonged to stebbins 3B type;S.hieracioides,2n=2x=32=12m+16sm+4st,karyotype belongs to stebbins 2B type.No satellites have been found in these six species.The chromosome number of S.polycolea var.acutisquama and S.columnaris is reported for the first time.

Abstract:The karyotypes were studied via squash method in 10 Prunus mume cultivars and 3 related species that P.armeniaca L.,P.sibirica (L.) Lam.and P.cerasifera Ehrh.‘Pissardii’.The results showed that ploidy levels of all the test materials were diploid (2n=2x=16).Asymmetry index ranged from 55.17% to 61.71%,The karyotypes of all the test materials were made of m and sm chromosomes,which include 1A,1B and 2B.The chromosome information of P.mume ‘Fenghou’ and P.mume ‘Qiao Meiren’ was between Prunus mume and 3 related species.

Abstract:Uing the ectomycorrhizae on Betula platyphylla in Inner Mongolia different areas as experimental material.The primary study on the diversity of ectomycorrhizas associated with B.platyphylla in Inner Mongolia area was investigated using morphological and anatomical and molecular method,then identification results were obtained according that the sequences were BLASTed using the GenBank and UNITE database.The results indicated that there are 13 different ECM fungi on B.platyphylla in Inner Mongolia area.Among the 13 identified ectomycorrhizal fungi,4 species belong to Ascomycotina and the rest species belong to Basidiomycotina,they belong to Cortinarius,Inocybe,Sebacina,Piloderma,Hebeloma and Cenococcum,Tuber,Geopyxis,respectively and among 13 different types,T₈ and T₁₁ failed to extract the DNA.So according to the map of ectomycorrhizal fungi which were built by Agerer and Haug,the two types were identified as Leccinum holopus and Betularhiza luteopinnata.The results shown that the diversity of ECM on B.platyphylla in Inner Mongolia area is higher,and it is different with the result which was identified by fruiting body associated with B.platyphylla.

Abstract:Genetic variation analysis for nut phenotype and nutrient was carried on using ninety-seven Chinese chestnut cultivars from ten province such as Shandong Province,et al.The results showed that:(1)There were extensive genetic variation among ninety-seven cultivars,and very significant differences between cultivars for nut phenotype and nutrient.Coefficients of genetic variation of traits were large,and the largest reached 0.378,indicated that the genetic potential were large;and the repeatability of characters were above 0.928,which showed that these were controlled by strong genetic factors.(2)There were significant positive correlation among phenotype characters,and also positive correlation among nutrient indexes,but there were negative correlation between the phenotype traits and nutrient indexes.Thus,phenotype and nutrient could be as two comprehensive factors which mutually independent and also has certain associations.(3)Forty-three cultivars were selected from ninety-seven cultivars through principal component analysis using eight indexes of nut phenotype and nutrient,and combined with the multiple comparison results.These cultivars have single or multiple advantages such as bigger nuts,or rich nutrient,or both,which can be chosen as excellent chestnut materials.

Abstract:In order to reveal the genetic diversity of wild peach,we conducted an experiment to analyze the 6 quantitative characters (weight of stone,transverse and vertical length,stone shape index,stone tip length,thickness) and 4 qualitative characters (stone shape,color,freestone,surface smoothness) of 23 wild peaches from Guizhou Province,China.The results showed that:(1)There was abundant in genetic diversity on the stone quantitative characters of wild peaches in Guizhou.The range of variation of the weight of stone was 0.65 to 4.38 g with the highest coefficient of variation of 33.08%,and the coefficient of variation of stone shape index was as low as 7.56%.(2)There were differences in stone shape,color,freestone by observing the stone morphology.The stone shape was ovate,obovate or oblong;the color was light brown,brown or dark brown;the freestone was free,semi-free or cling.The surface smoothness of stone had smaller range of variation,they were intermediate.(3)Correlation analysis among stone traits showed that weight of stone was definitely notable positive correlated to transverse length,vertical length,thickness;stone shape index was notable positive correlated to stone shape and stone tip length.（4）Principal component analysis indicated that the cumulative percentage of the former three main factors reached to 84.01%,which basically summarized the stone traits main information.(5)Cluster analysis showed that 23 wild peach samples could be divided into five categories,the ‘Qinglong-1’ and ‘Pu’an-5’ had grouped separately,which indicated that the genetic background of them were completely dissimilar to others.

Abstract:By using nested analysis,principal component analysis,correlation analysis and cluster analysis,we studied the phenotypic diversity,phenotypic variation and the relationship between phenotypic variation and microenvironment of the 21 phenotypic traits in 8 populations of Acer grosseri in Shanxi.The results revealed that:(1)There were significant differences in genetic variation in all phenotypic traits among populations and within population.The mean phenotypic differentiation coefficient (V_ST）was 50.16%,which was approximately equal to that within populations(49.84%).Coefficient of variation (CV) of all traits was from 7.89% to 37.04%,with the average of 19.74%.The seed traits of A.grosseri were stable than fruit traits and leaf traits.Shannon-Wiener information index was 1.692 3,which indicated that there was high phenotypic diversity in A.grosseri.(2)The correlation analysis showed that the phenotypic variation within populations appeared gradient regular changes,the shape of leaf blade from long ovate to broadly ovate shape,while fruits and seed got smaller with the rise of elevation.(3)The 8 populations of A.grosseri investigated could be divided into two groups according to the UPGMA cluster analysis,the phenotypic traits gather on the basis of geography distance.In summary,there is vast variation within the species of A.grosseri which was relevant to biological characteristics and distribution of the habitat.

Abstract:This study investigated the response features of alpine plant endogenous hormones,total nitrogen on time series and its relationship with growth under enhanced UV-B radiation by using the sample of Vicia unijuga collected from alpine meadow.The supplemental UV-B irradiation was 6.40 kJ/m² per day that simulated 9% stratospheric ozone depletion on clear summer solstice (Gannan,34°55′N,2 900 m),China.The results showed that:(1)The wild legume forage (Vicia unijuga) from alpine region could have stress response to enhanced UV-B radiation at the early stage of treatment.IAA,ZT,GAs,6-BA levels and total nitrogen content increased and were significant higher than that of control at the ten days of treatment.Meanwhile,the plant growth also increased,the plant height and biomass were significant higher than that of control.(2)After 10 days of treatment,the hormones decreased rapidly and reached to the lowest level up to 30 days of treatment.The total nitrogen content also decreased continuously to reach at a significant lower lever than that of control from 10 to 40 days of treatment.The plant growth was inhibited with the reduction of hormones level and the total nitrogen content.(3)ABA has not been detected until the treatment for 40 days.It suggested that the damage to membrane might be occurrence later.The study revealed that the some plant species from alpine region have undergone natural selection and made adaptation to the severe environment for a long term,and developed the special response mechanism to delay the damages to the plant caused by UV-B radiation.

Abstract:This paper aims at probing the effect of low temperature stress at booting stage of winter wheat on its physiological and biochemical characteristics and grain yield.‘Xiaoyan 22’ and other 4 cultivars were taken as tested materials.The superoxide dismutase (SOD) activity,peroxidase (POD) activity,catalase (CAT) activity,relative conductivity,MDA content,the soluble sugar content,the soluble protein content and the proline content were investigated after different time treatments (0 h,24 h,48 h),and the grain yield of 5 tested cultivars were also investigated.The results showed that:(1)After being chilled for 24 and another 24 hours,compared with the contrast,the SOD activity,POD activity,CAT activity,MDA content,relative conductivity,soluble sugar and proline contents increased significantly in the both chilled leaves;while the soluble protein content decreased significantly.(2)Low temperature stress at booting stage significantly decreased grain yield and the number of grain per ear,but the effects on the number of spike and 1000-grain weight was less significant.(3)Based on fuzzy mathematics method,‘Xiaoyan 22’,‘Aikang 58’ and ‘Xinong 509’ belong to high cold resistance group,and the other 2 cultivars,‘Zhengmai 9023’ and ‘Zhengmai 366’,belong to low cold resistance group.Which is accordance with the production in this experiment.Compared with low resistance wheat cultivars,the high cold resistance wheat cultivars showed higher antioxidation enzymes,lower negative effects on the cellular membranes,and higher osmotic adjustment,which may be the major physiological traits to have a relatively higher production after the low temperature stress.

Abstract:To examine the effects of temperature elevation on physiological and chemical characteristics of three species in alpine meadow on Qinghai-Tibetan plateau,we conducted a simulation study in situ with open top chambers (OTC) followed the method of International Tundra Experiment (ITEX) from November 2002 to September 2007,and these OTCs were designed 5 kinds of size with bottom diameters of 0.85,1.15,1.45,1.75 and 2.05 m so as to rise different air temperatures.(1)The air temperature inside OTCs increased by 2.68 ℃,1.57 ℃,1.20 ℃,1.07 ℃ and 0.69 ℃ with increase of OTC diameter compared with ambient air.Accordingly,the soil temperature was also increase by 1.74 ℃,1.06 ℃,0.80 ℃,0.60 ℃,0.30 ℃,compared with Control.(2)We found that the elevated temperature had significant and complicated effects on physiological-biochemical characteristics of three plant species,and these indexes varied between different species.(3)Their response to experimental warming was not exactly the same way.These results indicated that if the air temperature increased within the range of 0.69 ℃ and 1.07 ℃ in the future,it may have positive effects on the physiological-biochemical characteristics of plants,and thus the environment would be more adaptive for plants living in.

Abstract:To study the effects of elevated CO₂ concentration (CO₂) on the leaf photosynthesis and chlorophyll fluorescence parameters in Dracaena angustifolia and Philodenron selloum,we exposed the seedlings of D.angustifolia and P.selloum to either ambient CO₂［CK,(390±30) μmol·mol^-1］ or elevated CO₂［T₁,(780±30) μmol·mol^-1;T₂,(1 560±30) μmol·mol^-1］ in an open top chamber.The results showed that:(1)Leaf area and plant height of seedlings significantly raised with the increase of CO₂ concentration.(2)Under the high CO₂ concentration,the net photosynthetic rate (P_n) was higher earlier and lower later,but their stomatal conductance (G_s) and transpiration rate (T_r) significantly reduced.(3)The ratio of variable fluorescence to maximal fluorescence (F_v/F_m) and the actual photochemical efficiency (Φ_PSⅡ) tend to increased and then decreased with the CO₂ concentration raised.Photochemical quenching coefficient (q_P) also had the same trend,but the difference was not significant.On the contrary,non photochemical quenching coefficient (NPQ) tends to decrease earlier and increased later.The increasing CO₂ concentration in a certain extent might be beneficial for increasing net photosynthetic rate and the vegetative growth,but the promotion decreased slowly and then disappear if CO₂ enrichment prolonged.The performance of P.selloum seedling was more outstanding.It suggested that the higher CO₂ concentration could injure the structure of leaf photosystem Ⅱ and consequently decreased the leaf photosynthetic capacity in the late growth phase of D.angustifolia and P.selloum.

Abstract:With mono-embryonic of‘Jinhuang’and‘Guifei’,poly-embryonic of ‘Baixiangya’ and ‘Hongyu’ as test materials from the same age mango orchards and management conditions,we measured the quality characters of 30 fruits each plant,18 plants each variety after full bloom every week.We compared the variation of main quality characteristics between mono-embryonic and poly-embryonic during fruit development and ripe,in order to provide a theoretical basis for improving the quality of mango fruit and mango cultivation of new varieties.The results showed that:(1)Soluble sugar and soluble solids contents of mono-embryonic varieties mango fruit from the early development to the ripe stage were significantly higher than that of poly-embryonic varieties.(2)Titratable acidity increased firstly and then decreased during mango fruit developmental process.And the highest value of premature fruits and the final values in ripe period of mono-embryonic varieties are much higher than that of poly-embryonic varieties.（‘Hongyu’> ‘Baixiangya’>‘Guifei’>‘Jinhuang’）.(3)The solid acid ratio of mango fruits of all varieties are stable before ripe period and are rapidly rising to the highest,with the peak performance‘Jinhuang’(83.8%)>‘Baixiangya’(50.04%)>‘Guifei’(49.41 %)>‘Hongyu’(29.52%).(4)The peak and final values of carotenoid content of mango fruit in ripe period of mono-embryonic varieties were significantly higher than that of poly-embryonic varieties,and the yellow flesh of mono-embryonic varieties more obvious.Research shows that the mango fruit quality of mono-embryonic varieties is better than that of poly-embryonic varieties.

Abstract:A field experiment was carried out on dryland of loess plateau to study the effect of different nitrogen rates on nitrogen absorption and allocation of spring maize in double ridges mulched with plastic film.Six nitrogen rates are 0,100,200,250,300 and 400 kg/hm².The experimental results showed that:(1)The content of nitrogen and the nitrogen accumulation and kernel increased with the improvement of levels on nitrogen application,while the effect is not significant when nitrogen application exceed 250 kg/hm².(2)With the growing stage increasing,the nitrogen content of spring maize decreased while the nitrogen uptake of spring maize increased.(3)The nitrogen translocation amount and the transferred nitrogen contribution ratio of leaf and stem+sheath are higher than that of other organs.(4)With the increase of nitrogen application,the kernel yield increased firstly and then decreased.The kernel yield is the maximum when nitrogen rate is 250 kg/hm² and the kernel yield is 11 932 kg/hm².In addition,the nitrogen harvest index,nitrogen agronomic efficiency of the nitrogen level of 250 kg/hm² are higher than that of the nitrogen level of 300 and 400 kg/hm².From the consideration of spring maize yield,nitrogen utilization point of view,250 kg/hm² is a reasonable nitrogen rate.

Abstract:In order to explore the monosaccharide composition and contents in root exudates and plant tissue,four flue-cured tobacco varieties were used as the experimental material.The composition and contents of monosaccharide in rhizosphere,non-rhizosphere soils,root and leaves of each variety were analyzed with high performance capillary electrophoresis in pot experiment.Six monosaccharides analyzed in all of varieties,they were xylose,glucose,galactose,ribose,arabinose,and rhamose.The composition and contents of monosaccharide were different in rhizosphere soils,non-rhizosphere soils,root and leaves.In the same variety,leaves have the highest content,root takes second place,and rhizosphere,non-rhizosphere soils are the least.The correlation analysis show that there was a positive correlation between rhizosphere soils,non-rhizosphere soils,leaves and roots in total contents of xylose,arabinose,glucose,rhamnose and galactose.There was also a significant positive correlation between different monosaccharide for some of them.The results indicated that monosaccharides of root were secreted along with concentration gradient and diffused into rhizosphere.

Abstract:The sewage cleaning ability of 5 wetland plants,including Phragmites australis,Scirpus validus,Lythrum salicaria,Scirpus planiculmis and Typha angustata,were compared in constructed wetland simulated for domestic sewage treatment.The results demonstrated that:(1)The treatment system with wetland plants has higher removal efficiency to CODcr,ammonia nitrogen (NH₄⁺-N),total nitrogen (TN) and total phosphorus (TP) than that without wetland plants(P<0.05).The removal efficiency of 5 wetland plants were determined that ranged 80.2%～88.5%,98.4%～99.3%,68.8%～83.8%,89.7%～97.2% for CODcr,NH₄⁺-N,TN and TP,respectively.(2)The five wetland plants absorbed most of the phosphorus in sewage (89.7%～97.9%),and the surplus in sewage were very little (2.1%～10.3%).There was no retention in soil.The distribution of total nitrogen in sewage,plants and soils have very big difference.The total nitrogen absorption of P.australis,S.validus,T.angustata were higher(76.1%～83.4%) than that of L.salicaria,S.planiculmis (45.0%,46.8%).(3)For these 5 wetland plants,the ability of nitrogen accumulation is higher than that of phosphorus accumulation.The 5 wetland plants showed a distinct phosphorus and ammonium-nitrogen removal.The results of principal component analysis shows that P.australis,T.angustata and S.validus are the better ones among the five wetland plants in experiment of domestic sewage clean,followed by L.salicaria and S.planiculmis.

Abstract:In this study,10 Nitraria tangutorum populations in six important N.tangutorum distribution areas in Tsaidam Basin were selected as research objects,to make a comparison on the differences in leaf δ¹³C characteristics of different N.tangutorum populations and analysis the correlations between leaf δ¹³C and nutrients contents in leaf and soil,by measuring their leaf δ¹³C,leaf nutrients:organic carbon (C),nitrogen (N),phosphorus (P) and potassium (K) contents and soil nutrients:pH,organic matter (OM),total nitrogen(N),total phosphorus(P),total potassium(K),hydrolysis N,available P and available K contents.The results showed that:(1)there was a significant difference in leaf δ¹³C between different N.tangutorum populations,leaf δ¹³C varied from -27.66‰ to -25.47‰,and their leaf average δ¹³C was -26.66‰.(2)Leaf δ¹³C showed a extremely significant negative correlation with latitude,positive correlation with longitude and positive correlation with altitude respectively (n=10),thus latitude,longitude and altitude were important factors for leaf δ¹³C.(3)Leaf δ¹³C showed a negative correlation with leaf N,P and K contents,but this correlation was not significant (n=30),whereas leaf δ¹³C had a extremely significant correlation with leaf organic C content (n=30).(4)Leaf δ¹³C showed a extremely significant negative correlation between OM,total N and available K contents in surface soil (0~15 cm) (n=30) and a significant negative correlation between total P,hydrolysis N and available P in surface soil (0~15 cm)(n=30) respectively.In addition,leaf δ¹³C was extremely significantly correlated with OM and total N content in soil (15~30 cm),but it had no significant correlation with nutrients content in soil (30~45 cm).In general,latitude,longitude,altitude,leaf organic C content,soil total N,total P,hydrolysis N,available P and available K contents all had significant influence on δ¹³C in leaf of N.tangutorum.

Abstract:In order to understand the carbon sequestration of ecological forests in Loess Plateau of Gansu Province,we toke the different slopes (sunny and shady slope)and restoration duration(conversion of 6 years,9 years and 12 years) of Pinus tabulaeformis plantations as test objects and by the methods of plot investigation and biomass measurement.We studied the carbon content in different plant organs,shrub layers,grass layers,litter layers and soil layers and the carbon storage and its allocation in tree layer,shrub layer,grass layer,litter layer and soil layer.For the test plantations,the carbon storage content in different P.tabulaeformis organs ranged from 48.15%~53.90%,which in the order as follows:stem>leaf>fine-branch>thick-branch>stump>thick-root>bark>large-root>medium-root>small-root>fine-root>cone;in shrub layer was stem>leaf>root;in grass layer was abovegrond>underground;in litter layer was fresh>decomposing.The carbon storage in the soil profiles(0~100 cm) increased with plantation age but decreased with soil depth.There are significant different of difference slope positions in 0~10 cm and 10~20 cm.The total carbon storage in sunny and shady slopes of the 6-,9-and 12-year plantations was 42.90,50.50,59.22 t·hm^-2 and 45.08,53.77 and 65.70 t·hm^-2.It was considered that P.tabulaeformis had a good carbon sequestration function in sunny slope and shady slope.The shady slope was better than sunny slope and being able to be an ideal tree species in Loess Plateau of Gansu Province.

Abstract:Mining tailings are special ecosystems with harsh environmental conditions,the recovery of these ecosystems would broaden the scope of ecology.In this study,the relationship between soil seed banks and stand vegetation from different communities in Lanping Lead/Zinc Mining Area were explored by combining field investigations and seed germination trial.The results showed that:(1)The communities which recovered from tailing sites (CRTS) (including Poa pratensis man-made grassland,Artemisia princeps community and Coriaria nepalensis scrub) were lower in species number and plant diversity than reference communities (RC) (including Pinus yunnanensis forest and Quercus aquifolioides scrub,the natural vegetation in this site).(2)The soil seed bank of P.pratensis man-made grassland and A.princeps community were higher in species diversity than that of its stand vegetations.(3)Anemochorous plants dominated the soil seed banks and stand vegetations of CRTS,which means these plants would play important roles in vegetation recovery at the early stage of revegetation,and is mainly composed of Compositae and Poaceae.(4)CRTS were higher in similarity between stand vegetation and corresponding soil seed banks than that of RC,and lower in similarity between different vegetations and soil seed banks of different communities.These illustrate stand vegetation is tightly related with its soil seed banks at early stage of CRTS,and the mode of community building and succession time are two important factors influencing plant composition of soil seed banks.

Abstract:To study the impacts of different forest canopy conditions of Taiwania flousiana forest on Sinarundinaria basihursuta population,and reveal whether they affect the ramet structures and to estimate the effect sizes,we systematically conducted comparative survey about ramet population structures（including height,basal diameter,biomass allocation,leaf area and number of ramets） and age structure of S.basihursuta in:forest understory（FU,S=50.7 m²）,moderate gap（MG,S=160.4 m²）,large gap（LG,S=406.7 m²） and forest edge wildness（FEW,S=1 086.3 m²） of T.flousiana forest in Leigong Mountain Nature Reserve of Guizhou Province,Southwestern China.The main results showed that:(1)The height（h）,basal diameter （bd） and biomass of S.basihursuta ramet population significantly increased in the sequence of FU→MG→LG.(2)The modular biomass percentage of S.basihursuta ramets varied with different canopy conditions.Branch and leaf biomass percentage decreased in the order of FU→MG→LG→FEW.The biomass percentage of rhizome and roots in the FEW were both significantly higher than those in the other three canopy environments.(3)The ramet specific leaf weight significantly increased in the sequence of FU→MG→LG→FEW.In the MG,the individual leaf biomass was the heaviest and the individual leaf area the largest,followed by those in the FEW,both were respectively different from those in the FU or LG;Leaf number per ramet in the LG was the biggest and was significantly different from the other three canopy conditions;(4)The ramet population mortality was the lowest in the FU,while there was no significant difference in the average population age.All the results indicated that it was not ramet age,but the morphological changes and biomass distribution that exhibited the response of the ramet population of S.basihursuta to changed canopy conditions.

Abstract:This study aimed to uncover montane biodiversity and relations with the surrounding vegetation.Based on plot survey,floristic spectrum,diversity index,correlation and cluster analysis,plant floristic diversity of Laotudingzi were analyzed.The results showed that:(1)The occurrence of 1 006 wild seed plant species demonstrates that Laotudingzi have a high floristic biodiversity.It is notable in dominant family,the single-species and few-species genera of angiosperm are rich and it shows some relict phenomenon.(2)The distribution types of species 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,it fits North China flora from warm temperate.(3)Compared with adjacent mountains,floristic Shannon-Wiener index are obviously different from other 9 moutains,while simpson index are not.Shannon-Wiener index of Lushan and Culaishan are quite high,while Baishilazi and Changbaishan are low.(4)According to the relativity of different mountains flora,10 moutains correlation is significant at the 0.01 level,and the coefficients are between 0.617 and 0.995.Greater similarity was found among Laotudingzi,Qianshan and Fenghuangshan by cluster analysis,and they are all classified as North China flora.The present date indicated Laotudingzi should belong to subarea of North China montane flora.

Abstract:Based on 30 qualitative and 15 quantitative characters of Epimedium,a numerical taxonomy is presented by using the cluster analysis and principal components analysis.Results of cluster analysis show that:(1)The genus can be divided into macro-flowered taxon and micro-flowered taxon.The treatment of Sect.Macroceras,Sect.Polyphyllon and Subg.Rhizophyllum by Stearn is supported,and the taxonomic status of Sect.Epimedium is doubted.(2)In principal components analysis,cumulative ratio of the first three principal components is only 51.86%,and this is probably related to diversified variation and taxonomic complication in Epimedium evolution.However,the result of principal components analysis also indicates the generic division of macro-flowered and micro-flowered taxon.These important characters in Epimedium resulted from principal component analysis,such as ratio of petal length to inner sepal length,spur,whorls of sepal,are valuable for taxonomy of this genus.

Abstract:In order to develop a simple and fast as well as adequate epidermal preparation technique,seven different preparation methods were adopted to prepare fruit epidermal specimens of Malus xiaojinensis for light microscopic observation of its morphological features.A comparison between these methods indicated that four of them,namely acid eduction method,nail polish blotting method,scraping method,and boiling peeling scraping method,could yield clear epidermal structure under microscope.And the effect of production with boiling peeling scraping method was significantly better than that of other methods.Thus the boiling peeling scraping method is considered as the most applicable one to prepare specimens for Malus fruit epidermis.Besides,it has such advantages as easy sampling,simple procedure and high efficiency.

Abstract:One species of Elsholtzia,Elsholtzia blanda Benth.,is reported as a new record to Sichuan,where is also the northern boundary of its distribution.E.blanda has been previously known from the tropical area of Southwest China (Yunnan,Guizhou,and Guangxi) to Southeast Asia and South Asia.The voucher specimen is hold in CSH.

Abstract:Retrotransposons in eucaryon are mobile genetic elements with ubiquitousdistribution,these elements can amplify themselves via RNA intermediates and increase their copy numbers in genome.In high plants,retrotransposon is an important component of genome.Retrotransposons can be divided into five types,the LTR retrotransposons,an important subclass of transposable elements,are well suited for computational identification,as they contain two long terminal repeats (LTRs) and features such as PBS,PPT,GAG and POL open reading frames,TSD.Recent research indicated that methylation of LTR retrotransposon and environments seemed to be affecting the jump of retrotransposons.Retrotransposons could be inhibited by high degree of DNA methylation and activated by environments,which influence the function of surrounding genes.The characteristics of LTR retrotransposons,such as ubiquitous distribution,abundant copy number and insertional polymorphism in plant species,provide an excellent basis for the development of molecular markers,e.g.,RBIP,SSAP,IRAP,REMAP.In this review,we summarize the recent progress about the types and structures of retrotransposons,inhabitation and activation of LTR retrotransposons and their computational identification,molecular marker development.