Abstract:In order to clarify the specific regulation mechanism of TaCO91A gene in wheat growth and development, this study successfully obtained the orthologous gene TaCO9 of the barley (Hordeum vulgare) photoperiod gene HvCO9 in wheat (Triticum aestivum) by homologous cloning． Bioinformatic analysis, subcellular localization, transcriptional activation, and expression pattern analysis were performed． Arabidopsis was transformed by Agrobacterium infection, and phenotypic analysis was performed on the overexpressing lines． The results showed that: (1) TaCO9 contained 2 exons and 1 intron, the whole length of CDS was 876 bp, 291 amino acids were encoded, and the protein sequence contained a unique CCT domain, which was highly conserved among different species． (2) Bioinformatic analysis showed that the molecular weight of the protein encoded by this gene was about 30．7 kD and the pI was 6．24． The prokaryotic expression results showed that the molecular weight of the protein was basically consistent with the predicted results under IPTG induction; The promoter region of TaCO9 contained many cisacting elements such as light response, hormone response and stress response. (3) Subcellular localization and transcriptional activity analysis showed that TaCO9 was mainly located in the nucleus, and TaCO9 had transcriptional activation activity． (4) The results of qRTPCR showed that TaCO9 gene was expressed in all tissues, with the highest expression in leaves; TaCO9 expression level under 14 h light was significantly higher than that under 10 and 12 h light; and TaCO9 expression level in ovary and grain of ‘Xinong817’was significantly higher than that under ‘Chinese Spring’． (5) Three transgenic lines were obtained by hygromycin screening; Functional identification showed that the flowering period of transgenic Arabidopsis plants with overexpression of TaCO9 was later than that of wildtype control plants (3-4 d), and the seeds and siliques were larger．

Abstract:1433 protein is an important signal transduction regulator in plants and plays significant roles in carbon metabolism, stress response, growth and development, etc. In order to indepth analysis the biological function of 1433 protein family in cassava, we constructed the prokaryotic expression vector pET30aMeGRF3 of MeGRF3, a member of cassava 1433 protein family, via enzymes digestion and ligation, and then transformed it into Escherichia coli Rosetta (DE3) strain by heat shock method to induce the expression of MeGRF3 fusion protein. The purified MeGRF3 fusion protein was used to immunize the New Zealand male rabbits to prepare the polyclonal antibody, and then the titer and specificity of polyclonal antibody were detected. The results showed that: (1) the prokaryotic expression vector pET30aMeGRF3 of cassava MeGRF3 was successfully constructed, and the fusion protein with MeGRF3 and six His tags was induced and expressed. (2) The MeGRF3 fusion protein was mainly in the form of inclusion body, and its molecular weight was about 33 kDa. (3) The antibody titer determined by indirect enzymelinked immunosorbent assay (ELISA) was 1 024 000. (4) The bands with the same molecular weight of MeGRF3 were detected in leaves, stems, barks and roots of cassava via Western blot, indicating that MeGRF3 was expressed in all of the four tissues, but mainly accumulated in the stems and roots. The results showed that the MeGRF3 polyclonal antibody successfully prepared in this study had good specificity.

Abstract:Crystal leaf mutants of Cymbidium ensifolium have high ornamental value due to their leaves being white transparent shape, but their formation mechanism is not clear. Taking C. ensifolium ‘Tiegushuijing’ as the material, this study intends to explore the reasons for the formation of crystal leaf mutants of C. ensifolium by observation of microstructure and ultrastructure and RNAseq. The results showed that： (1) the crystal leaves of C. ensifolium ‘Tiegushuijing’ were thinner than the green leaves, the number of mesophyll cells was significantly reduced, the cell shape was irregular, and the chloroplast content was small, a significant reduction in the number of stomata in the epidermis of the crystal leaf than the green leaves; the chloroplast structure of mesophyll cells in crystal leaves was poorly developed, the chloroplast double membrane and thylakoid membrane were blurred, and there were a large number of osmiophilic granule in the cells. (2) The RNAseq data results showed that the expression levels of genes related to photosynthesisantennae and photosynthesis metabolic pathways were decreased in crystal leaves, while the expression levels of genes related to pigment metabolic pathways were increased. We speculated that the reason for the formation of crystal leaves of C. ensifolium is that the expression of genes related to photosynthesis are reduced, the chloroplast is poorly developed, and the chlorophyll synthesis is blocked, thereby forming white transparent leaves.

Abstract:To study the molecular mechanism of photosynthesis, we cloned a wheat Lhca gene from the leaves of ‘Bainong207’ using RTPCR, and was designated as TaLhca. The coding sequence (CDS) of this cloned Lhca gene is 810 bp in length, encoding a polypeptide of 269 amino acids. The deduced protein molecular weight was 29.31 kD and its theoretical isoelectric point was 8.69. Bioinformatics analysis showed that TaLhca is a hydrophilic nonsecretory protein with three transmembrane domains and a chlorophyll a/b binding domain. Multiple sequence alignments and phytogenetic analysis of Lhca proteins showed TaLhca is most similar with Lhca from Brachypodium distachyon and Oryza sativa. Cisregulatory element analysis revealed that light responsiveness elements, stress responsiveness elements are in the promoter region of TaLhca. The results of Realtime PCR analysis suggested that TaLhca expressed in root, stem and leaf, with the highest level in leaf, while the lowest level in root. Interestingly, the expression of TaLhca could be strongly induced by NaCl, drought, ABA and H₂O₂ and low temperature stress, while down regulated by darkness treatment. This results provided references for better understanding on the mechanism of photosynthesis and gene expression in wheat.

Abstract:In this paper, we studied the plantlets of potato variety ‘Qingshu 9’ under simulated drought stress to explore the molecular mechanism of potato stem under drought stress, respectively, and the stems of plantlets were used for transcriptome sequencing. The results showed that: (1) the contents of proline, soluble sugar and soluble protein were increased with the increasing concentration of PEG6000. Under three different droughtstressed conditions, there were more downregulated candidate genes than upregulated candidate genes with a total of 657 differential expression genes (DEGs) in potato stem. (2) GO enrichment analysis showed that the DEGs in potato stems mainly focused on oxidationreduction process, response to hormone, oxidoreductase activity, glycosylhydrolase activity. KEGG pathway enrichment analysis showed that the DEGs in potato stems mainly involved in plant hormone signal transduction, phenylpropanoid biosynthesis, zeatin biosynthesis, phenylalanine metabolism, starch and sucrose metabolism, biosynthesis of secondary metabolites. (3) Realtime fluorescence quantitative PCR (qPCR) was used to verify the expressions of six DEGs under different droughtstress conditions. The results were basically consistent with the transcriptome profile that proved the reliability of our RNAseq data. Our research provided the valuable information for understanding the drought resistance mechanism of potato, and enriching the genetic resources of drought resistant potato breeding.

Abstract:We used noncoding chloroplst DNA sequence (trnLtrnF and trnDtrnT) to study the genetic diversity of 16 populations of Salix psammophila distributed in Mu Us Sandy land and Kubuqi deserts,which aimed to explore genetic diversity, structure and differentiation characteristics of this species. This study provide theoretical basis for genetic management, improvement, breeding and variety selection of S. psammophila. The main results showed that： (1) the length of combine sequences was 1 811 bp, a total of 12 nucleotide mutation sites were identified and 16 haplotypes were recovered, including 8 simple information sites and 4 mutation sites. (2) The haplotype diversity was 0.737. The nucleotide diversity was 0.001 07. Only haplotype H3 located in the center of the haplotype network map distributed in all populations, while other haplotypes were randomly distributed among the populations. (3) AMOVA analysis suggest that 91.16% of the total variation existed within population while among population variation was medium (F_ST = 0.088 37). The exchanging of gene between the populations was very frequent (N_m=2.58). There is significant phylogeographic structure in population of S. psammophila. (N_ST=0.085, G_ST=0.056, 0.01 < P < 0.05). (4) Neutral tests and mismatch analysis proved that the distribution of S. psammophila population did not expand significantly.

Abstract:The genetic diversity and genetic structure of Petrocosmea qinlingensis artificial breeding population and wild population were analyzed with 24 SCoT primers， This study is of scientific significance to analyze the endangered mechanism of the P. qinlingensis and to formulate population protection and restoration strategies. The results showed that: (1) the average of observed number of alleles, effective number of alleles, Neis gene diversity and Shannon information index of 60 P. qinlingensis test samples were 1.51, 1.31, 0.230 5 and 0.370 3, respectively. This indicates that the genetic diversity of the test material population was low. (2) The analysis results of genetic distance and similarity coefficient among populations showed that the genetic similarity coefficient between 60 test materials of the three populations was 0.955 1 to 0.970 5, and the average similarity coefficient was 0.963 4, which further explained that the genetic similarity among populations was extremely high. Therefore, the genetic background was narrow. (3) The results of molecular variance analysis of P. qinlingensis population showed that 15% of the variation was from among populations, and 85% of the variation was from within population. The comprehensive analysis showed that the genetic diversity of the P. qinlingensis was low in various groups and between populations, and the genetic background was narrow. This may also be one of the important reasons for its poor ability to adapt to the environment, leading to its endangerment.

Abstract:The morphological characteristics of peristome and spores of 10 species of Dicranum Hedw. were observed by light microscope (LM) and scanning electron microscope (SEM). The results show that: (1) the capsules of 10 species of Dicranum are cylindrical. (2) The spores are spherical, near spherical, orellipseor triangular ovate, they are yellow, brown, oryellowish brown; the faces near pole concave, the ornamentation is verrucous, granular, spore. (3) The peristome of 10 species of Dicranum mostly are lanceolate, some are broad lanceolate. These peristomes are apricot yellow, oxblood red, browinish yellow or reddish brownin color; the ornamentation is striate and verrucous, perforated into a net structure. Some species are smooth and lack of perforation, with verruca on the surface. The studies provide a basis for the taxonomic division of Dicranum and basic information for the taxonomic classification and evolution of bryophytes.

Abstract:The study used seeds of Paeonia rockii treated with different concentrations of gibberellic acid (0，100，300，500 mg/L) and different temperatures (normal 25，30，40 and 50 ℃). The change of seed rooting rate of each treatment was investigated, and the ultrastructure of seed embryo at different rooting stages was observed by transmission electron microscopy(TEM). The ultrastructural changes of seed embryo in the process of dormancy release of Paeonia rockii seeds and the correlation between the changes and dormancy release were explored. Result show that: (1) GA₃ and warm water treatment significantly advanced the rooting time, and 300 mg/L GA₃ and 40 ℃ warm water treatment had the best rooting effect, 14.7 and 16.0 d earlier than the control, and the rooting rate was 62.33% and 67.00%. (2) The results of optical microscope showed that GA₃ and warm water treatment had no significant effect on the shape and arrangement of the upper and lower epidermal cells of the cotyledons, but the thickness of the cotyledons was thinner and the vascular bundle structure was obvious. The best rooting effect was 300 mg/L GA₃ and 40 ℃. (3) TEM showed that the lipid in the cotyledons of the seeds of Paeonia rockii was degraded in the early stage of germination and the lipid bodies were distributed around the cell wall in different sizes. The number of lipid bodies was obviously reduced. The nucleus was clear, a small number of mitochondria appeared, protein began to accumulate in the cytoplasm, and around the vacuole formation of protein deposits. In the later stage of seed germination, the matter in the cotyledons of seed embryo is dense, the lipid bodies have been degraded and fused into a larger mass, the nutrients stored in the cells are basically degraded completely, endoplasmic reticulum, golgi body, mitochondria and other organelles appeared. The structure is more complete, which indicates that the material metabolism activity in the cells is strengthened at this time and the seed dormancy is relieved. The results showed that the germination rate of seeds could be significantly improved by soaking seeds in 300 mg/L GA₃ and 40 ℃ warm water, and the effect of soaking seeds in 40 ℃ warm water was better, so it was better to use more warm water soaking method in actual production.

Abstract:In order to investigate the resistance and sensitivity of Primula forbesii Franch. to heavy metal cadmium (Cd) pollution, and to provide a theoretical and practical basis for the application as a new type of fragrant ground cover plant in Cd contaminated soil, we conducted a pot experiment to determine the growth and physiological indicators of P. forbesii seedlings under Cd stress in different concentrations (0，5，50，100，150，200 mg/kg) of soil. The results showed that：(1) low concentration (5 mg/kg) Cd stress could promote plant height and root length; however, the plant height, root length and biomass were significantly reduced under high concentration (≥150 mg/kg) Cd stress. (2) With the increase of Cd concentrations, leaf photosynthesis, chlorophyll content, SOD and CAT activities of P. forbesii seedlings increased firstly and then decreased, while its superoxide anion radical production rate, hydrogen peroxide content, malondialdehyde content, leaf relative conductivity and POD activity continued to increase. (3) Under Cd stress, the contents of K and Zn in P. forbesii decreased; the contents of Ca and Mg in leaves and roots increased significantly; the content of Cd increased obviously, and the Cd content in roots was much higher than that in leaves and petioles. This study shows that P. forbesii seedlings have a certain tolerance to Cd stress. Low concentration (5 mg/kg) Cd stress has little effect on the growth of P. forbesii, but high concentration (≥150 mg/kg) Cd stress has an obvious toxic effect on P. forbesii and affects its normal growth. However, P. forbesii may reduce the damage caused by cadmium stress and improve its tolerance by enhancing the activity of antioxidant enzyme system in vivo, with increasing the content of Ca and Mg in leaves and roots as well as the cadmium interception in roots.

Abstract:The purpose of this study was to investigate the response mechanism of carbonnitrogen metabolism on different drought and shading conditions for A. indica seedling, and enrich the theoretical basis for exploring the matter conversion and metabolic pattern of A. indica. In this work, twelve potted plants with four drought stress levels and three light levels were set up to determine the activities of major carbonnitrogen metabolism enzymes, the contents of some metabolites, and index of growth. The results showed that： (1) under the condition of drought stress, A. indica can maintain a smaller variation in height and diameter by regulating the activities of carbonnitrogen metabolism enzymes such as Sucro synthase (SS), Sucrose phosphate synthase (SPS), Nitrate reductase (NR), glutamine synthetase (GS), glutamate synthase (GOGAT), as well as accumulate of more soluble sugar, soluble proteins and free prolines. (2) Under the condition of shading, slight shading can lead to a sharp decline in the activities of the carbonnitrogen metabolites and the contents of metabolites in A. indica leaves, which severely inhibits the growth of seeding. (3) Under the conditions of drought stress and shading, shading (drought stress) can alleviate the adverse effects of drought (shading) on the primary metabolism and growth of A. indica to some extent. Our research found that A. indica has a strong drought resistance, appropriate drought stress (SRWC＞35%) can promote cell carbonnitrogen metabolism, but not conducive to the accumulation of organic matter. Meanwhile, seedling has a high demand for light, and slight shading will affect its carbonnitrogen metabolism and growth seriously. In the process of seedling cultivation in the future, we suggested that should provide as much water and light as possible. The negative effects of drought on seedling growth can be mitigated by shading, while insufficient light needs to properly control the water.

Abstract:The effects of temperature on seed germination, seedling morphological and physiologicalbiochemical indexes were studied by different constant temperatures (15 ℃,25 ℃,35 ℃) and variable temperatures (25 ℃/15 ℃, 30 ℃/20 ℃, high and low temperature for 12 h respectively) controlled experiments in laboratory. This paper also discussed the influencing mechanism of temperature on seed germination and seedling growth of Rhododendron agastum. The results showed that: (1) the condition of variable temperature 25 ℃/15 ℃, the seed germination rate (87.69%) and exponential value (8.65) was the highest. (2) The variable temperature 25 ℃/15 ℃ is beneficial for ground diameter, seedling height, average root length and twig increase, and biomass accumulation of roots, stems and leaves of R. agastum. (3) After the seedling leaves was treated at variable temperatures 25 ℃/15 ℃, the total leaf chlorophyll, soluble sugar and soluble protein contents were the highest, while the MDA content, CAT activity and SOD activity was lower. The research showed thatthe optimum temperature for seed germination and seedling growth of R. agastum was 25 ℃/15 ℃(day/night). The growth was significantly inhibited at high temperature (35 ℃) and low temperature (15 ℃).

Abstract:To study the effects of exogenous salicylic acid (SA) on salt tolerance physiology of Ulmus pumila seedlings under NaCl stress, we explored the effects of 0, 0.5, 1.0 and 2.0 mmol·L^-1 SA on the photosynthetic rate and ion distribution of annual U. pumila seedlings under different NaCl concentrations (0, 50, 100 and 150 mmol·L^-1). The results showed that: (1) NaCl stress significantly inhibited the growth and photosynthetic capacity of U. pumila seedlings, and the ion balance was destroyed. (2) After spraying exogenous SA, the dry weight and rootshoot ratio of U. pumila seedlings increased in varying degrees. 0.5 and 2.0 mmol·L^-1 SA improved the chlorophyll and carotenoids pigment contents in leaves of U. pumila seedlings under 50 and 100 mmol·L^-1 NaCl stress． (3) The net photosynthetic rate (P_n), stomatal conductance (G_s) and transpiration rate (T_r) of U. pumila seedlings significantly increased with the addition of 0.5 mmol·L^-1 SA under 50 mmol·L^-1 NaCl treatment. And 1.0 and 2.0 mmol·L^-1 SA have better improvement effect on the net photosynthetic rate (Pⁿ) of seedlings under 150 mmol·L^-1 NaCl, while the exogenous SA had no significant effect on the photosynthetic parameters under 100 mmol·L^-1 NaCl. (4) The content of Na⁺ and the ratios of Na⁺/K⁺, Na⁺/ Ca²⁺, Na⁺/ Mg²⁺ in leaves and roots of U. pumila were reduced by using exogenous SA under salt stress, while the ionselective transport coefficients S_K，Na, S_Ca，Na and S_Mg，Na were increased which promoted the transfer of K⁺, Ca²⁺, and Mg²⁺ from roots to leaves. Membership function analysis found that the SA concentrations with the best improvement effect on the ion content in leaves and roots of U. pumila were 1.0 and 2.0 mmol·L^-1, respectively. Therefore, appropriate concentration of exogenous salicylic acid can improve the photosynthetic capacity and regulate the ion state of U. pumila seedlings effectively under NaCl stress, thus enhancing the resistance of U. pumila to NaCl stress.

Abstract:In this study, we conducted pot experiments to study the accumulation and translocation characteristics of dry matter and mineral elements (N, P and K) of ‘Xingyu1’, a droughtsensitive cultivar, and ‘Xingyu2’, a droughtresistant cultivar, under drought stress in order to provide theoretical reference for efficient watersaving cultivation of Canna edulis. The results showed that： (1) drought stress significantly suppressed C. edulis growth, decreased both dry matter accumulation of rhizomes, stems and leaves, and its distribution ratio in rhizomes, while those in root increased. (2) At the same time, the uptake and accumulation of N, P and K also declined significantly and the reduction of P was less than that of N and K. The distribution ratios of N, P and K among organs changed obviously as well. Under drought conditions, the leaf was the priority organ of N distribution, the P and K distributed to leaf and root firstly. (3) Simultaneously, the effect of drought on the accumulation and distribution of dry matter and N, P, K had obvious difference between two cultivars. The droughtresistant cultivar ‘Xingyu2’was affected less than the droughtsensitive cultivar ‘Xingyu1’, but the reduction of K distribution ratio in rhizome of ‘Xingyu2’ was higher than that in ‘Xingyu1’. (4) The rehydration effect on the leaf and root was more obvious than on the rhizome, the effect of rehydration on P was better than on N and K, but short time rehydration could not compensate the damaging effects of drought. These results indicated that drought increased the distribution ratio of mineral elements in leaf and root and enhanced osmotic regulation capacity to improve its droughttolerance under the drought conditions. The K use efficiency of ‘Xingyu2’ was lower than that of ‘Xingyu1’ under the drought conditions.

Abstract:In order to exploit the salttolerance ability of Chionanthus retusus, we studied the plant growth, distribution patterns of Na⁺ and K⁺ and relative conductivity and osmotic adjustment substances of C. retusus under different concentrations (50, 100, 200, 300 mmol·L^-1) of NaCl solution with potted twoyear seedlings. The results show that: (1) with the increase of NaCl concentration, the seedling growth of C. retusus decreased gradually; the salt damage index increased and the survival rate decreased. Salt tolerance threshold of seedling was 98.693 mmol·L^-1 (0.577% W/V). (2) The content of Na⁺ in every organof seedlings increased continuously. At 50mmol·L^-1, it was roots > leaves > stems, and in other treatment groups was leaves > roots > stems. At the same time, the content of K⁺ in roots and leaves showed a trend of increasing firstly and then decreasing. The content of K⁺ in stems decreased in general, and the content of K⁺ in organs showed roots > leaves > stems. In addition, the selective ion transport capacity from root to stem and stem to leaf and the K⁺/Na⁺ ratio in each organ showed a decreasing trend. (3) With the increase of NaCl concentration, the contents of soluble sugar and soluble protein in leaves of C. retusus seedlings increased in general, and the proline content showed an upward trend and then a downward trend. It is concluded that under salt stress, the root system of C. retusus seedlings can balance the damage of salt stress by enlarging the root growth; the root system can prevent the salt damage by absorbing and accumulating Na⁺ to the aboveground parts; the leaf and stem can increase theselective absorption and accumulation of K⁺, thereby increasing the ratio of K⁺/Na⁺ to slow down the physiological metabolism of salt damage.

Abstract:In order to optimize anthocyanin purification process, we used the grains of five black rice varieties as materials and a single factor experiment design to investigate the effect of various factors of resin adsorption in the purification of black rice anthocyanin. The yields of purified anthocyanin of brown rice and husk in different varieties were compared. Then, the antioxidant activities of anthocyanin from different varieties were analyzed by 1,1diphenyl2picrylhydrazyl (DPPH) method. Finally, PCR was used to detect the key structural genes in anthocyanin synthesis pathway of black rice so that to clarify the yields and antioxidant characteristics of anthocyanin from brown rice and husk of five different black rice varieties and this will provide technical support for the development and utilization of anthocyanin in black rice. The results showed that: (1) the optimum purification condition for extracts of black rice anthocyanin was 4 h of static adsorption equilibrium, 1.5 h of the desorption time, 2.5 of pH, 30 ℃ of temperature, 70% ethanol of eluent. (2) The highest yield of anthocyanin in brown rice came from Fuheixiangnuo (213 μg/g), however, to husk from Guchengheinuo (226 μg/g). Meanwhile, Guchengheinuo possessed the highest total yield of anthocyanin, 432 μg/g. (3) The DPPH clearance rate of anthocyanin in brown rice was 65.1%, and it in husk was 73.7%. The DPPH free radical scavenging capacity per gram anthocyanin freezedried powder from brown rice and husk were equivalent to 3.694 mmol and 4.208 mmol vitamin E, respectively. The antioxidant capacity of anthocyanin from husk increased by 13.9% compared with that from brown rice. (4) In the identification of the five key structural genes of anthocyanin synthesis pathway for five black rice, it was found that there was no flavonoid3′hydrogenase gene (OsF3′H) in Aixuenuo. And its anthocyanin yield in rice husk was also the lowest (125 μg/g) compared to the other four varieties, and it is suggested that OsF3′H may be related to the anthocyanin content came husk of black rice.

Abstract:Based on the investigation of Limonium aureum populations under Haloxylon ammodendron plantations, we studied the development pattern characteristics of the populations in noncrusted sand (early stage NSC1, late stage NSC2), physical crusted sand (early stage PSC1, late stage PSC2) and biological crusted sand (early stage BSC1, late stage BSC2) during the soil crusts development in order to master the influence of soil crust development on population development and the planting technology of the vegetation under H. ammodendron plantations. The results showed that: (1) the soil crust development had a significant promoting effect on the population density. The valuereached the maximum in BSC1 plot, while it had a promoting effect on the individual crown width in the early stage and a inhibiting effect in the late stage. It reached the maximum in NSC2 plot, thus leading to the instable change of the total population coverage. (2) The development value of population individual increased firstly and then decreased, and reached the maximum in NSC2 plot. In the development process of NSC1NSC2 promoted the population individual development and the value gradually increased, while in the development process, NSC2BSC2 can inhibited the population individual development and the value gradually decreased. (3) The dominant layer of the population is located in the lower layer, with the soil crust development. The value increased firstly and then decreased. The peak value is in BSC1 plot, while the higher the population layer is, the peak value gradually moved to the earlier stage, and the peak value is in NSC2 or PSC1 plot. The above analysis showed that the soil crust development promoted the population density, but it promoted the population individual development in the early stage and inhibited in the later stage. The conclusion had positive guiding significance for the establishment of the L.aureum vegetations under H.ammodendron plantations.

Abstract:The species richness of woody plant was investigated in an area desertified at different gradients in Beipan River Basin of Guizhou Province via the method of cluster analysis, and the adaptive capability of different tree groups was clarified according to the desertification of their habitat. The study results indicated that: (1) the biodiversity expressed in families, genera and species decreased with the desertification extent increasing. In specific, desertification increased the species number of the deciduous plants, the nanophanerophyte and the microphanerophyte, but decreased the evergreen plants, the mesophanerophyte and the megaphanerophyte. (2) Forty six dominant species were divided into 8 functional groups when the Euclid Distance equaled 6.5. There were 3 functional groups with 21 tree species in the area slightly desertified, 3 functional groups including 14 tree species in the medium desertified area, and 2 functional groups including 10 tree species in the heavily desertified area.

Abstract:To explore the coupling relationship between forest community characteristics and species diversity, three typical communities (Pure forest of B. pendula ［PFB］, we selected Mixed forest of B. pendula with Populus laurifolia ［MFBP］, and Mixed forest of B. pendula with Salix alba ［MFBS］), in brich forest national forest park Irtysh river, to survey the community characteristics (height, tree bole height, diameter at breast height, crown width, coverage, and others). According to these indices, richness index, diversity indexes and evenness indexes were calculated, and canonical correspondence analysis (CCA) was performed. The results showed that: (1) the maximum height and clear tree bole height of the arbor layer and the canopy coverage and ground diameter of the shrub layer all occurred in MFTS; there were significant differences in the herb layer (except base diameter); the herb coverage of the MFBS was 19.1% and 51.8% higher than that in the MFBP and PFB. (2) In three different forests, the important value of Betula pendula in the arbor layer was maximal, and the dominative species in the shrub layer were Rosa laxa and Crataegus altaica, and that in the herb layer was Carex bohemica. (3) The mean species richness, Simpson index and ShannonWiener index of the arbor layer and Pielou index, Alatalo index of the shrub layer showed the same pattern, i.e., MFBS ＞ MFBP ＞ PFB. However, the herb layer exhibited a different order, not include Alatalo index, with PFB ＞ MFBP ＞ MFBS (P ＞ 0.05). (4) CCA showed that the correspondence associations between community characteristics and species diversity differed among the three forest types. In the pure forest of B. pendula, tree clear bole height, the height and crown width of the shrub, height of the herb had the highest impact on species diversity. In the mixed forest of B. pendula with Populus laurifolia, the height and crown width of the tree, shrub crown width and herb height had the highest impact on species diversity. In the mixed forest of B. pendula with Salix alba, the DBH, the crown width and coverage of the shrub, the height of herb had the highest impact on species diversity. The results showed that for all three forests the characteristics of the tree clear bole height and crown width of the shrub and herb height had a substantial influence on plant species diversity.

Abstract:In this paper, we used morphology, anatomy, lichen chemistry and phylogeny methods to study the specimens collected from Xinjiang, China. Divarictic acid was detected from some collections by Color test (CT), thin layer chromatography (TLC) and high Performance Liquid Chromatography (HPLC). Morphological characters, secondary metabolites, and phylogenetic tree of ITS of the specimens showed that some specimens should be identified as Oxnerella safavidiorum. Therefore, the genus Oxnerella with species O. safavidiorum are reported for the first time from China. Descriptions with photos of the thallus, apothecia, asci and ascospores are provided based on Chinese collections. In addition, the relationships of the species and its related species are discussed.