Abstract:The TLP15 was cloned from the resistant variety of Chinese wild Vitis quinquangularis ‘Shang24’ and the susceptible variety of Vitis vinifera cv. ‘Red Globe’ by RTPCR, named VqTLP15 and VvTLP15 (GSVIVT01018769001), respectively. We studied the gene by bioinformatics analysis, subcellular localization analysis, transformed Arabidopsis thaliana to observe and analyze transgenic Arabidopsis resistance to different pathogens. We also analyzed the expression of related genes involving in the SA or JA/Eth signaling pathways and regulating stomatal movement by qRTPCR. The results showed: (1) the open reading frame (ORF) of the VqTLP15 was obtained. VqTLP15 showed 98.99% and 99.66% sequence homology to VvTLP15 cloned from V. vinifera cv. ‘PinotNoir’ and VvTLP15 cloned from V. vinifera cv. ‘Red Globe’ by amino acid sequence alignment, respectively. (2) Subcellular localization indicates that VqTLP15 was localized in the cytoplasm. (3) VqTLP15 transgenic A. thaliana (L₁, L₂, L₃) were successfully obtained. (4) Inoculation observation showed that the transgenic A. thaliana lines were inoculated with G. cichoracearum and found to have greater resistance than Col0 to powdery mildew at 7 days postinoculation, and the concentration of powdery mildew spores from infected leaves were significantly lower in the transgenic lines than that in Col0. The leaf necrotic damage (43%) induced by Botrytis cinerea was significantly greater than that of Col0 in transgenic lines (71%, 62% and 67% of lesion area > 40% in L₁, L₂ and L₃, respectively). After PstDC3000 inoculation, the disease symptoms were less apparent in the transgenic lines than in Col0. The reduction of leaf stomatal aperture were greater in the transgenic lines than in Col0, and the concentration of bacteria was lower in the transgenic lines than in Col0. (5) A histochemical staining assay showed: Callose deposition was more widely distributed, and the frequency of cell death and O₂^-· levels were higher in the transgenic lines than in Col0 after powdery mildew inoculation. The extent of cell death, and levels of H₂O₂ and O₂^-· were higher in the transgenic lines than in Col0 after B. cinerea inoculation. After PstDC3000 inoculation, the frequency of cell death and the degree of O₂^-· accumulation were both higher in the transgenic lines than in Col0. (6) qRTPCR results showed: after powdery mildew inoculation, the expression levels of both PR1 and ICS1 increased in the transgenic lines, PR1 expression peaked at 72 hpi, and ICS1 peaked at 120 hpi. And the expression levels of LOX3 gradually decreased to the lowest level at 120 hpi in the transgenic lines, but remained higher than in Col0. The expression levels of PR1, NPR1 and PDF1.2 all increased following B. cinerea inoculation, and peaked at 48 hpi, and the expression levels of LOX3 decreased, but remained higher than in Col0. After PstDC3000 inoculation, PR1, PDF1.2 and NHL10 expression were all more highly expressed in the transgenic lines than in Col0, but WRKY53 expression was lower in the transgenic lines than in Col0. The expression levels of COI1, FRK1, ATPPC2, FLS2 and OST1 were higher in L₁ than in Col0 following PstDC3000 inoculation. After treatment with flg22 or LPS, the expression of COI1 was lower in L₁ than in Col0, but the expression levels of ATPPC2, FLS2, OST1 were higher in L₁ than in Col0. This study showed that overexpression of the VqTLP15 reduced the sensitivity to powdery mildew and PstDC3000 and increased the sensitivity to B. cinerea. VqTLP15 may involve in the defense response of plants via mediating salicylic acid (SA) and jasmonic acid / ethylene (JA / Eth) signaling pathways and stomatal immune response, and may present a candidate for future grape molecular breeding for disease resistance.

Abstract:The CONSTANS (CO) and CONSTANSlike (COL) genes play a key role in photoperiod regulation of flowering. In this study, A CO ortholog, OnCOL2, and two COL paralogs (OnCOL8 and OnCOL9) were isolated from Jinhui, a variety of Oncidium, encoding 326, 411 and 291 amino acids, respectively. The bioinformatics analysis showed that they were predictively unstable proteins and located in the nucleus. OnCOL2 and OnCOL8 contained two Bbox domains of Zinc finger and one CCT domain, while OnCOL9 lacked Bbox domain. The multiple sequence alignment and phylogenetics analysis showed that all COLs could be divided into three groups, and OnCOL2, OnCOL8 and OnCOL9 were divided into two different groups. OnCOL2 shared highly identity with Cymbidium ensifolium CeCOL (90.77%). OnCOL8 and OnCOL9 were closer in evolutionary relationship, and exhibited the highest similarity with AtCOL9 and AtCOL10 in Arabidopsis, respectively. They were extremely conservative in the Bbox and CCT domains. Expression analysis showed that OnCOL2, OnCOL8 and OnCOL9 had the highest expression in flowers, roots and pseudobulbs, respectively. Their expressions in leaves showed a periodic trend, and the peak values and time were different under longday and shortday conditions. In the flower bud differentiation stage of Oncidium, their expressions were significantly upregulated in leaves. These results indicated that OnCOL2, OnCOL8 and OnCOL9 were regulated by circadian clock and day length, and their expression upregulated could probably promote the flower bud formation of Oncidium in the photoperiod pathway. The results provide the basis for further study on gene function and photoperiod regulation of flowering mechanism of Oncidium.

Abstract:Based on the third generation genome of longan (Dimocarpus longan), we isolated the cDNA sequence of AGO4 gene from longan embryogenic callus (cultivar:‘Honghezi’) by reverse transcription polymerase chain reaction (RTPCR) and analyzed the bioinformation. Furthermore, we analyzed the expression profiles in somatic embryogenesis, different tissues, hormones treatment, abiotic stress, and 5azac (5azacytidine) treatment. The results showed that: (1) The cDNA length of DlAGO4 was 3 425 bp, which contained an open reading frame of 2 781 bp and encoded 926 amino acids. (2) The bioinformatic analysis showed that it was basic, hydrophilic and nonsecretory protein, containing PAZ and Piwi conserved domains, had 85 phosphorylation sites and 2 glycation sites, while shared high homology with CcAGO4 of Citrus clementina. The subcellular localization was predicted to be located in the nucleus, and microRNA prediction showed that DlAGO4 was regulated by four miRNAs. (3) qRTPCR results indicated that the relative expression of DlAGO4 was upexpressed in the globular embryos (GE) and seeds in Longan, while KT, salicylic acid, NaCl, mannitol, PEG4000 and ABA treatments could promote the expression, but 2,4D and MeJA treatments inhibited the expression. After treated with 5azac, the expression of DlAGO4 was downregulated in cultured 1 d and 3 d, but upregulated from cultured 6 d, and significantly increased in cultured 12 d. These results suggested that DlAGO4 might be involved in the transcriptional regulation of globular embryo stages and seeds development of longan. Furthermore, DlAGO4 might be involved in hormone, abiotic stress responsiveness and DNA methylation regulation.

Abstract:Carboxylesterases (CXE) are a class of hydrolase enzymes with α/β folding domains, which play key roles in plant growth and stress response. In this study, Populus trichocarpa was used as material. The CXE genes of P. trichocarpa were identified by TBLASTN search and manual correction, and then the basic characteristics, gene structure and expression pattern of the CXE gene family were analyzed. The P. trichocarpa CXE proteins expressed in E. coli were purified by affinity chromatography, and then the CXE activity was determined by fluorescence method and pH indicator method, respectively. This study laid foundation for further revealing the function of the forest tree CXE gene family. The results showed that: (1) a total of 52 CXE genes were identified from the P. trichocarpa genome, and the 52 CXE proteins all contained a complete α/β hydrolase domain. The 52 P. trichocarpa CXE genes were divided into 3 types, each had 39, 4 and 9 CXE genes, respectively. (2) The distribution of CXE genes on the chromosomes of P. trichocarpa is uneven. Among them, 28 CXE genes are distributed on 6 chromosomes in the form of gene clusters, and the remaining 24 CXE genes are scattered on 16 chromosomes. (3) Among all the 52 CXEs, expression of eight CXE genes were not detectable in the xylem, phloem, leaf, shooting and root of P. trichocarpa, while the other 44 CXE genes were differentially expressed in the five tissues. (4) Five CXE proteins (PtCXE4, 5, 6, 41, and 43) were expressed in E. coli, and then purified to detect activity. PtCXE5 was found to catalyze the largest number of natural substrates. All the five purified proteins can catalyze the hydrolysis of 4MU acetate and 4MU butyrate, but none of them can catalyze the hydrolysis of 4MU laurate and 4MU palmitate. The CXE showed lower catalytic activity towards substrates with longer carbon chains. The pHdependent analysis of enzyme activity showed that the catalytic activities of the five proteins increased with the increase of pH in the range of pH 6.0-9.0. This study provides new insights into the functions of carboxylesterase gene family.

Abstract:In this study, the chitosan oligosaccharide (COS) induced resistance to Pst DC3000 was investigated in SPINDLY deficient Arabidopsis mutant spy3. From multilevel indices, including phenotype data, the disease index, the bacterial numbers in infected leaves and the expression of Pst DC3000 marker genes. The function of SPINDLY in COS induced resistance was systematically investigated. The results showed that: (1) spy3 mutant was more susceptible to Pst DC3000 infection than wild type. (2) Compared with the Mock+Pst group, COS pretreatment significantly relieved the leaf symptoms, inhibited the proliferation of Pst DC3000, and reduced the disease index. (3) SA and JAmediated pathway related genes and the contents of SA and JA were upregulated significantly in COS pretreated spy3 plants. (4) The effect of COS induced resistance in spy3 has no significant difference compared with wild type. The results suggested the essential role of SPY in plant innate immunity. However, COS still effectively induce the disease resistance in spy3.

Abstract:Perennial ryegrass (Lolium perenne) is a coldseason gramineous species, and its distribution and yield are severely affected by temperature stress. Transcription factors (TFs) can regulate gene expression, playing important roles in plant acclimation to stress. Here, we used the perennial ryegrass cv Yatsyn to analyze the TF genes and their response patterns under heat (40 ℃), cold (-10 ℃), control (22 ℃) by highthroughput RNA sequencing, and to screen adverse tolerance candidates of TF genes. The results showed (1) 694 TFs unigenes were identified, belonging to 32 families such as AP2/ERF, GTF, HSF, MYB, NAC, WRKY, bHLH and bZIP, etc. (2) Upon heat and cold stresses, the gene expressions of most members of the ERF (AP2/ERF), MYB, NAC and bZIP families increased, while the WRKY family decreased. In addition, most members of the HSF, GTF and DREB (AP2/ERF) family genes were upregulated by heat, while most bHLH family members elevated by cold. (3) The functional enrichment results indicated that temperatureresponsive TFs were mainly involved in plant hormone signaling, plant circadian rhythms, and plantpathogen interaction. In general, the TF genes involved in stress adaptation were usually upregulated, while most genes involved in growth and disease resistance were downregulated. This study revealed a corner of the response mechanism of plants to temperature stress at the transcriptional level, and provided substantial candidate tolerance genes for the improvement of perennial ryegrass and other plants.

Abstract:Genetic structure and genetic diversity 252 individuals in 17 natural populations of Cymbidium kanran distributed in Jiangxi Province were studied by using chloroplast genome fragment (petbpetd) and nuclear genome ITS sequence. It provide some suggestions for the analysis of the reason of the decrease in the number of wild C. kanran in Jiangxi Province and the protection and rational utilization of wild cold orchid resources. The results showed that： (1) there were a total of 652-658 bp of nrDNA ITS sequences, with 140 variable loci, the percentage of variation loci was 21.3% to 21.5%, and the content of (G+C) was 58.9% to 67.1%. The sequence length of cpDNA was 522-529 bp, with 9 variable loci, the percentage of mutation sites was 1.70%-1.72%, and the content of (G+C) was 32.9% to 33.7%. (2) Molecular analysis of variance (AMOVA) showed that the genetic variation within populations was greater than that between populations, the genetic variation of cpDNA was 40.76% among population and 59.24% within population the genetic variation of ITS was 28.96% among population and 71.04% within population; While gene flow was high, cpDNA: N_m=1.226 5; ITS: N_m=0.726 7. (3) Through the mismatch analysis of ITS and cpDNA data, it is shown that the wild population of Cymbidium kanran Makino has experienced an expansion event recently. ITS sequence of nrDNA evolved faster and mutated faster than chloroplast DNA sequence.

Abstract:The karyotypes of 43 populations in 11 Polygonatum species native to China were studied using traditional squash method．The results showed that: (1) all of those 43 populations were diploids, with the number of chromosomes between 16 and 60, base n=8, 9, 10, 11, 12, 13, 15, 17, 30. (2) Among those 43 populations， 15 populations belonged to Stebbins 2B karyotype; 22 populations belonged to 3B karyotype，and the rest 6 populations belonged to 2C karyotype. The AS．K and the ratio of the length of the longest and the shortest chromosome were 55.78％-75.60％ and 2.01-6.12. (3) Among those 43 populations，23 populations had different numbers and positions satellite. (4) The chromosome number of Polygonatum species native to China increased gradually from alternate leaves to verticillate leaves, and the karyotype characteristics trend showed in: ① the ratio of the length of the longest and the shortest chromosome increased gradually. ② Satellite gradually disappear. ③ Karyotype asymmetry enhanced gradually. ④ The AS．K increased gradually. Above results indicated that, numbers of chromosome morphology diversity existed among different species or different populations of the same species． The genetic diversity among different species or populations could be discriminated by means of the number and position of different kinds of chromosomes， as well as the difference numbers and positions of satellite．

Abstract:In order to understand the adaptability of Rhododendron aganniphum var. schizopeplum to strong ultraviolet radiation and alpine environment, we studied the anatomical structures of leaves from nine altitude gradients in Sejila Mountain, Southeastern Tibet by the method of paraffin section. Ten anatomical structure indexes of leaves were measured and analyzed by plasticity index and correlation coefficient. The results showed that: (1) the leaves of R. aganniphum var. schizopeplum were bifacial, the upper epidermis had obvious cuticle, the lower epidermis had trichomes, and the palisade tissue cells had 2-3 layers. (2) As the altitude became higher, the thickness of cuticle, epidermis, palisade tissue, sponge tissue and leaf increased obviously. However, the density and porosity of the tissue structure did not change significantly, and the protuberance of the main vein decreased. (3) The plasticity index showed R. aganniphum var. schizopeplum had lower plasticity, which represented weak adaptability to environment. (4) The indexes were significantly correlated with each other and presented obvious coevolution, except that there were no significant correlations between the thickness of sponge tissue and palisade tissue, between the thickness of lower epidermis and upper cuticle. In summary, R. aganniphum var. schizopeplum adapts to the extreme environment, survives in harsh alpine habitats and becomes a eurytopic species by means of increasing the thickness of cuticle, epidermis, mesophyll and anatomical structure indexes.

Abstract:We analyzed the changes of osmotic regulators and sucrose metabolizationrelated enzymes (SPS, Ss+, Ss-, NI, AI and SP) in leaves of G. uralensis. With G. uralensis seedling as the test material, CK, LS, MS and SS were designed for drought stress treatments by potted natural drought method, to explore the osmotic regulation of G. uralensis and the enzymatic mechanism of sugar regulation, and to demonstrate the response mechanism of G. uralensis to drought stress. The results showed that: (1) the contents of soluble sugar, soluble protein and proline in G. uralensis leaves increased with the aggravation of drought stress, while the ratio of bound water to free water increased first and then decreased. (2) The contents of sucrose, glucose and fructose in G. uralensis leaves increased first and then decreased with the aggravation of drought stress, but the peak time of different stress intensity was different. Sucrose content > starch content > glucose content > fructose content under drought stress of CK and LS, starch content > sucrose content > fructose content under drought stress of MS and SS, indicating that with the increase of drought, sucrose in G. uralensis leaves was transformed into starch. (3) With the aggravation of drought stress, the SPS activity in G. uralensis leaf first increased and then decreased. Ss activity and Inv activity showed a gradually increasing trend, while SP activity showed a gradually decreasing trend. In different drought stress levels, Ss+ and CK showed no significant difference, while Ss- and CK showed significant difference, and Ss-activity was much higher than Ss+ activity under various stress conditions, indicating that the Ss- activity in G. uralensis seedlings leaves played a major role. (4) According to the results of correlation in LS, NI and negatively correlated with sucrose, Ss- with starch was significant positive correlation, negative correlation with sugar. In MS, sucrose and glucose were positively correlated with SPS, Ss+, Ss-, NI and AI, and negatively correlated with SP. Under SS, SP and NI were positively correlated with sucrose and negatively correlated with starch. The results showed that Ss participated in sucrose decomposition and starch synthesis under LS. Under MS and SS, SP mainly catalyzes the decomposition of starch to increase sucrose content and balance sucrose metabolism.

Abstract:This study compared the growth and flavonoid accumulation of Astragalus membranaceus var. mongholicus from Wengniute Banner, Chifeng City, Zhenglan Banner, Xilin Gol League and Guyang County, Baotou City of Inner Mongolia Autonomous Region, Hunyuan County, Datong City, Shanxi Province, and Luxi County, Dingxi City, Gansu Province, and analyzed the rhizosphere soil microorganisms by Illumina MiSeq highthroughput sequencing in different growth stages. The results showed that: (1) during growth period, the A. membranaceus var. mongholicus in Guyang, Hunyuan and Chifeng grow faster, root dry weight peaked in September, there was little difference between provenances of other biomass indicators. (2) The content of calycosin7Oβglucoside in the roots of Longxi and Hunyuan provenance was higher and peaked in September. Other components (ononin, calycosin and formononetin) were fluctuating. (3) There was a great influence on the microbial community in the rhizosphere soil at different growth stages of A. membranaceus var. mongholicus. The rhizosphere bacteria had the most obvious influence which the diversity was higher in September, and the difference in fungal communities was relatively small. While the rhizosphere microbial community composition was similar among different provenances. This study showed that the content of calycosin7Oβglucoside of A. membranaceus var. mongholicus was significantly increased during the growth period, so the best harvest period should not be too early. And the difference of microbial community structure may be one of the important factors for obtaining growth advantage and accumulation of active constituents of A. membranaceus var. mongholicus.

Abstract:Rosa roxburghii fruit is a good source of high quality dietary fiber. This research was to determine the content and composition of dietary fiber during the development of ‘Guinong 5’ R. roxburghii fruit and its response to light. The results showed that： (1) during the whole development of the fruit, the percentage of total dietary fiber and insoluble dietary fiber increased in the young fruit stage 40 days after anthesis, and then decreased continuously with the rapid development of fruit, showing a consistent trend of change and accounting for 24% and 16% of the dry weight of fruit at the time of maturity, respectively. However, soluble dietary fiber changed steadily during the fruit development, and remained at about 8% of the dry weight. (2) Dietary fiber components such as cellulose, hemicellulose and lignin also showed a continuous downward trend during the whole development of the fruit, while pectin had a rapid accumulation process 20 days after flowering, and cellulose and hemicellulose were the main components of the fruit when maturing, accounting for about 60% of the total dietary fiber. From the changes of the total amount of dietary fiber and its main components in single fruit, the main period of dietary fiber accumulation in R. roxburghii fruit was 60 days after anthesis. (3) The analysis of monosaccharide components of dietary fiber showed that galactose and glucose were the main total dietary fiber and insoluble dietary fiber, while mannose was the main soluble dietary fiber, showing great differences. Fruit bagging and shading promoted the accumulation of soluble dietary fiber and lignin in different degrees, but had no significant effect on total dietary fiber, insoluble dietary fiber, cellulose and hemicellulose in fruits. (4) The content of dietary fiber was higher in the young fruit stage, and then continued to decrease with the development of the fruit. Shading can promote the accumulation of lignin and soluble dietary fiber.

Abstract:With tomato cultivar ‘Jinpengchaoguan’ as the experimental material, foliarspraying 0.25 mmol·L^-1 spermidine (Spd) were applied to the seedlings, which grows under high temperature condition (38 ℃/28 ℃, day/night). The effects of foliarspraying Spd on the growth, the contents of chlorophyll precursors, key enzyme activity and the content of chlorophyll of tomato seedlings were discussed. The results showed that: (1) foliarspraying Spd significantly alleviated the decrease of shoot weight of tomato seedlings under heat stress, but it had no significant effect on root weight. (2) The contents of chlorophyll precursors δaminolevulinic acid (ALA) and porphobilinogen (PBG) in tomato leaves increased significantly under heat stress, but the contents of uroporphyrinogen Ⅲ (UroⅢ), protoporphyrin Ⅸ (Proto Ⅸ), Mgproto Ⅸ (Mgproto Ⅸ) and protochlorophyll (Pchl) decreased significantly under heat stress. The results indicated that chlorophyll synthesis blocked site was from PBG to UroⅢ, which might cause the reduce of chlorophyll a (Chla), total chlorophyll (Chlt) and Chla/Chlb. (3) Foliarspraying Spd increased the activity of porphobilinogen deaminase (PBGD) of seedlings under heat stress, which effectively alleviated the hindrance of heat stress on the transformation from PBG to UroⅢ, and promoted the synthesis of chlorophyll precursors after PBG. In summary, this study showed that tomato growth and chlorophyll synthesis were significantly inhibited under heat stress. This inhibition could be relived through foliarspraying Spd, which could alleviate the transformation from PBG to UroⅢ. This process promoted the synthesis of chlorophyll precursors, resulting in increased amount of chlorophyll and less inhibited growth of tomato plants under heat stress.

Abstract:Fine roots play an important role in plant nutrient acquisition and ecosystem carbon allocation. Here we clarified the variation patterns of root traits based on root order or root functional modules, as well as the relationship between root traits and mycorrhizal colonization of different ectomycorrhizal tree species. This study determined the changes in branchingbased and functionbased root traits and ectomycorrhizal (ECM) colonization of six coexisting temperate tree species. The results showed that: (1) root diameter and individual root length increased, while specific root length and root branching intensity decreased from the first to fifth order roots. There were significant differences between studied tree species within the same root order for all root traits, especially two gymonsperms (Pinus tabuliformis and Larix gmelinii) had thicker root diameter than other four angiosperms. (2) Absorptive fine roots (AFR) and transport fine roots (TFR) both showed that, for a given tree species, all root traits existed significant differences; among tree species, root diameter, specific root length (SRL) and root tissue density existed significant differences, but individual root length and root branching intensity had no significant differences. (3) ECM colonization was the highest in Larix gmelinii and the lowest in Carpinus cordata and Betula platyphylla. Moreover, ECM colonization was significantly positively correlated with root tip diameter and negatively correlated with SRL. These results have shown that the variation patterns of branchingbased and functionbased root traits among species were not completely consistent. Individual root length and root branching intensity for AFR and TFR had no significant differences among tree species. Additionally, the coefficient of variation of specific root length and root branching intensity of AFR was larger than that of other root traits, indicating these two root traits are more sensitive to environmental changes. Tree species of basal clades tend to produce thicker root diameter and rely more on mycorrhizal fungi.

Abstract:Habitat changes, soil nutrient redistribution, and corresponding plant growth and nutrient feedback effects under different site conditions have important effects on the cycle of soilplant chemical elements. In this study, we used A. wudanica as the research object to study the stoichiometry characteristics of leaves and roots and its relationship with soil nutrients under different slope conditions. The results showed that: (1) from sunny slope to shady slope, N, C∶P and N∶P in leaves of A. wudanica gradually decreased, soil C content, C∶P and N∶P gradually increased. For soil P content and soil C∶N, there was no significant difference between different aspects. (2) The leaf P content and root system P content, C∶P, N∶P were extremely significantly correlated. There was a significant negative correlation between leaf N content and soil C content, and a significant positive correlation between root P content and soil C and N contents. (3) The contents of C and N in leaves decreased with the increase of soil nutrient content, and the contents of P in leaves and N and P in roots increased with the increase of soil nutrients. The correlation between C content and C∶N in leaves and soil was greater than that in roots. The slope aspect has an important effect on the growth of A. wudanica, and the stoichiometry of A. wudanica is linearly related to soil nutrients. Different slope aspects caused a certain range of fluctuations in the stoichiometry of A. wudanica, but the overall ecological stoichiometry was stable, and the growth of sunny slope A. wudanica was restricted by nitrogen and phosphorus.

Abstract:The plant functional traits and environmental factors is great significance for understanding the formation of plant community and its adaptation mechanism under different environmental gradients. Therefore, in this study, the Potentilla fruticosa shrub meadows was taken as the research object, and we analyzed the variation trends and interrelationships between the leaf functional traits of herbaceous plants and soil factors in different coverage gradients of P. fruticosa shrub plaques (coverage in shrub plaques was 0%, 30%, 60% and 90%) under the influence of grazing. Our research indicates that: (1) there were significant differences and different variation trends among soil bulk density (BD), soil pH, and soil nutrients under different coverage gradients of P. fruticosa shrub. And P. fruticosa shrub in the study area has obvious “Fertile Island effect”. (2) With the increase of P. fruticosa shrub overage, the specific leaf area (SLA) increased significantly, and leaf thickness (LT) and leaf phosphorus content (LPC) decreased significantly (P <0.05). The difference of LPC may be related to the element content of different species in the community. (3) SLA is negatively correlated with leaf dry matter content (LDMC) and LT to varying degrees, and is extremely significantly negatively related to leaf nitrogen and phosphorus content (LNC, LPC) (P <0.01), and significantly positively correlated with leaf carbon content (LCC) (P<0.01). (4) RDA redundancy analysis showed that the average explanatory variable of soil factors to leaf functional traits variation was 72.25%, and the dominant factors affecting plant functional traits were soil organic matter (SOM), soil total nitrogen (TN), soil available nitrogen (AN), and soil available potassium (AK) and soil bulk density (BD). However, with different cover distributions of P. fruticosa shrub, the dominant factors affecting plant leaf traits are different in different communities. Communities with 0% and 30% coverage of P. fruticosa shrubs were more affected by SOM, TN, and AN, while the communities with 60% and 90% of P. fruticosa shrubs were more affected by AK and BD.

Abstract:The young ovary wall of Cucurbitaceae plants, including cucumber, melon, watermelon and West Indian cucumber, were used as the material for chromosome preparation. Several main factors including sample size of ovary material, 8hydroxyquinoline pretreatment time and enzymatic hydrolysis time were investigated to analyze their effects to chromosome preparation results, and we also explore how to optimize this method. Using this method, ploidy identification and fluorescence in situ hybridization experiments were carried out on the ovary wall of candidate haploid plants of cucumber. Results show that: (1) the best pretreatment time of young ovary wall is 1 h 30 min for cucumber, 1 h for melon, 55 min for watermelon, 45 min for West India cucumber. To observe clear mitotic metaphase with this optimized method, we should use melon ovary with a length range of 0.2-1 cm, cut the ovary wall material into small pieces with a side length of 1-1.5 mm. And the suitable time for enzyme digestion is 1 h 10 min to 1 h 20 min. (2) The identification results by this method showed that the cucurbitaceae plants cucumber, melon, watermelon and West Indian cucumber had 14, 24, 22 and 24 chromosomes, respectively. The somatic cell chromosome number in the plant identified as haploid was 7. (3) Fluorescence in situ hybridization showed that there were 3 pairs of bright 45S rDNA hybridization signals and 1 pair of 5S rDNA hybridization signals in cucumber chromosomes, and the number of corresponding signals in haploid cucumbers was 7. There were 2 pairs of 45S rDNA and 1 pair 5S rDNA signals in melon, watermelon and West Indian cucumber. Our studies indicated that the ovary wall chromosome preparation procedure is suitable for all these Cucurbitaceae species. Not only can they obtain good mitotic metaphase, but also have the advantages of easy to get material and high chromosome preparation efficiency. Therefore, when it is difficult to obtain root tips of the rare material, the ovary wall chromosome preparation method is an effective method for studying the chromosome number of plants and identifying ploidy. This method is also suitable for fluorescence in situ hybridization.

Abstract:Based on detailed collection and identification of Plagiotheciaceae of Mts. Sygera, four species, namely Plagiothecium latebricola, P. piliferum, P. platyphyllum, and Herzogiella seligeri, respectively, were reported new to Tibet. The morphological characters and geographical distributions of the four species were discussed, and the related illustrations were provided. The voucher specimens were deposited in the herbarium of China Agricultural University (BAU).

Abstract:The investigation of plant diversity in high altitude areas of the QinghaiTibet Plateau is insufficient. When we conducted plant diversity survey in Anjiu_La Shan Pass, Ranwu Town, Baxoi Country, Xizang. We found a parasitic plant. After consulting the literatures and checking the typus specimens, we finally identified it as Mannagettaea hummelii H. Smith (Orobanchaceae). Mannagettaea is distributed in China (Gansu, Qinghai, Sichuan) and Russia (Sayanling region). The genus is a new distribution record to Xizang, and the result enriched the flora of Xizang. Meanwhile, it also raised the altitude up to 4 459 m. The voucher specimens are kept in the Herbarium of Kunming Institute of Botany (KUN).

Abstract:Several new records were found during our plant resources investigation in Houhe National Natural Reserve in Wufeng County of Hubei Provinces. In this paper, we report four new records of woody plants. They are Parakmeria lotungensis (Chun & C.H. Tsoong) Y.W. Law, Michelia chapensis Dandy, Carpinus omeiensis Hu & Fang and Lagerstroemia caudata Chun & F.C. How ex S.K. Lee & L.F. Lau. Meanwhile, we carried out some field survey about the population status, endangered status and resource utilization for further protection.

Abstract:Shoot branching is an important factor in determining plants morphogenesis, which is a process which axillary buds develop into branches, regulated by various factors such as light, nutrients and hormones. Recent studies have found that TCP (TEOSINTE BRANCHED1, CYCLOIDEA, PCF) transcription factor family member BRC1/TB1 can respond to and integrate a variety of signals to regulate plant branching. This article summarize the response of BRC1/TB1 to different environmental factors and its central role in regulating plant branching, with focus on the related research on the regulatory networks of BRC1/TB1 gene, and the future research directions have been prospected, aiming to guide the research on future regulation.