Abstract:CBLCIPKs are universal proteins in higher plants that decode Ca²⁺ signals. Base on the previous work, a series of investigations of BnaCIPK15 gene in Brassica napus L., including subcellular localization, bimolecular fluorescence complementation (BiFC), yeast twohybrid (Y2H) and qRTPCR, were carried out to explore its role in ABA hormone response. (1) Subcellular localization result showed that BnaCIPK15 protein was localized in the cytoplasm and nucleus. BiFC assay demonstrated that BnaCIPK15 interacted strongly with BnaCBL1/3/4/9 proteins, and interacted weakly with BnaCBL10 protein as well. (2) Using qRTPCR, the expression pattern of BnaCIPK15 gene was examined under various phytohormone and abiotic stress treatments, and the results revealed that abscisic acid (ABA) and cold stress significantly induced its expression. Moreover, a mild upregulation of BnaCIPK15 gene was also observed by paraquat, reactive oxygen species (H₂O₂) burst and heat stress treatments, suggesting that BnaCIPK15 gene may be involved in the regulation of ABA and cold stress. (3) Y2H assay discovered that BnaCIPK15 protein interacted with BnaHAB1, which belongs to the protein phosphatase type 2C family negatively regulating ABA signaling pathway, and did not show any evident interaction with BnaABFs/AREB3/ABI5 transcription factors. At the same time, BiFC assay also showed that there were interaction signals between BnaCIPK15 and BnaHAB1 proteins, rather than BnaHAB2 protein, which proved that they had specific interaction, suggesting that BnaCIPK15 protein might be involved in regulating ABA signal transduction. In conclusion, this study identified that BnaCIPK15BnaHAB1 module may be involved in ABA signal transduction and regulatory network in Brassica napus.

Abstract:PNP oxidase is an important invertase in the VB₆ metabolic pathway. In this study, the tea tree ‘Longjing 43’ was used as the material, and the PNP oxidase gene was cloned by RTPCR. The prokaryotic expression vector was constructed by using pET22b(+) as a vector, and induced expression by IPTG for functional identification; Fluorescence quantitative PCR was used to analyze the differential expression of CsPNPO gene in different tissues of tea plants and its expression under low temperature and drought stresses, which laid a foundation for further analysis of physiological and biochemical functions of tea tree VB₆. The results showed that: (1) the coding frame length of CsPNPO was 1 503 bp, and it was predicted to encode a 501 amino acid protein. The molecular weight of CsPNPO protein was 48.5 kD, and the theoretical isoelectric was 5.82. The CsPNPO protein contains no signal peptide and is a nonsecreted hydrophilic protein, and localized to chloroplasts. Amino acid sequence analysis revealed that it has a chloroplast transit peptide region, a YjeFN functional domain, and a PNP oxidase functional domain. (2) The prokaryotic expression vector pET22b(+)CsPNPO was successfully constructed, and the recombinant protein had strong PNP oxidase activity at pH 8.5 and 37 ℃. (3) Fluorescence quantitative PCR detection shows that the expression level of CsPNPO gene in tea leaves was the highest, followed by stems, and the expression in roots was only one tenth of that of leaves, indicating that CsPNPO gene has tissue expression specificity; The expression level of CsPNPO gene decreased significantly under low temperature and drought conditions. It is speculated that CsPNPO gene may be involved in the stress response of tea tree to low temperature and drought.

Abstract:In this study, we used potato double haploid ‘DM’ as material to clone the complete cDNA of highaffinity nitrate transporter gene StNRT2.1(JGI accession number PGSC0003DMT400002924). Expression pattern and bioinformatics analysis of the StNRT2.1 gene were constructed in this study, which provided a theoretical foundation for further exploration of the biological functions of the StNRT2.1 gene and improving the efficiency of nitrogen utilization in potato. The results showed that: (1) complete cDNA fragment of StNRT2.1 gene was obtained by homologous cloning and PCR amplification, and the expression vector pCEGFPStNRT2.1 was constructed. From the sequencing results, it was found that the actual encoded protein sequence was identical with the target protein sequence in the database, indicating that StNRT2.1 gene was cloned successfully without missense mutation. (2) StNRT2.1 gene is located on the chromosome 11 of potato and cDNA sequence was 1 593 bp in length encoding 530 amino acids. The relative molecular mass of the protein is about 57.60 kD, and the theoretical isoelectric point is 9.36. (3) Bioinformatics analysis showed that StNRT2.1 consisted of 20 different amino acids, of which glycine (Gly) accounted for the most, reaching 10.8%, and mainly consisted of 228 αhelix, 27 βsheet, 87 extended chain and 188 irregular coils. Moreover, the functionally conserved structure MFS_1 (PF07690) and 12 transmembrane helix domains are present, and the Nterminus and Cterminus are located in the cell membrane. StNRT2.1 is predicted to be located in the cytoplasm without signal peptide. Therefore, it may be a nonsecret membrane protein. (4) Compared with sufficient nitrogen level (7.5 mmol/L), potato seedlings showed obvious phenotypic changes including yellowed leaves and shorter plant with the three week treatments of nitrogenfree (0 mmol/L) and lownitrogen (0.75 mmol/L) level. (5) The results of realtime PCR showed the expression of StNRT2.1 gene in root tissue increased 3.98 times with the nitrogenfree treatment, which suggesting that StNRT2.1 may be an inducible highaffinity transporter.

Abstract:Previous transcriptome analysis has revealed that a TCP7like gene is highly expressed in the ray florets of Chrysanthemum morifolium. In order to clarify the presence or absence of ray florets and its molecular regulation mechanism in the formation of chrysanthemum capitulum, we cloned the TCP7like gene from C. morifolium ‘Fen Ditan’ by RTPCR and RACE, and named CmTCP7 (accession number: MK140598). The open reading frame (ORF) of CmTCP7 was 786 bp, encoding a protein consisting of 261 amino acids with a typical helixloophelix TCP domain. CmTCP7 was a hydrophilic unstable protein which belongs to class Ⅰ of plantspecific TCP family and primarily localized to the cell nucleus. The results of quantitative realtime PCR showed that CmTCP7 was highly expressed during floral bud differentiation of chrysanthemum, suggesting that CmTCP7 may be involved in the formation of floral buds. During the flowering time, CmTCP7 was found to be highly expressed in ray florets, especially in ray petals, indicating that CmTCP7 may promote the growth of ray petals and participate in the formation of zygomorphic ray florets.

Abstract:CML is an important Ca²⁺ response protein. In order to investigate the effect of CML protein on selfincompatibility in Primula, we screened PmCML19 and PfCML19 genes from Primula maximowiczii and P. forbesii respectively. Fulllength cloning, bioinformatics analysis, subcellular localization and expression pattern analysis of the two genes were performed. The results showed as follow： (1) the full length of PmCML19 and PfCML19 genes were 435 bp, and the similarity of their amino acid was 80.56%. Both of them were acid hydrophilic proteins and had four EFhand motifs. Homology analysis showed that the closest relationship with PmCML19 and PfCML19 was AcCML19 of Actinidia chinensis, while the similarity of amino acid sequences between PmCML19, PfCML19 and AtCML40 were 44% and 46% respectively. (2) The results of subcellular localization indicated that both PmCML19 and PfCML19 genes were expressed in the nucleus and cell membrane. (3) Realtime fluorescence quantitative PCR results demonstrated that the expression of PmCML19 and PfCML19 in anther were much higher than that in pistil. And the expression of PmCML19 and PfCML19 in compatible pollination pistils was higher than that in incompatible pistils. Based on these results, we speculated that CML19 gene of P. maximowiczii and P. forbesii is closely correlated with selfincompatibility in Primula, which provides a new idea for studying the genetic mechanism of heterotypic selfincompatibility.

Abstract:The genetic diversity and genetic structure of 4 wild seedling populations of Rhododendron molle (64 individuals) from 3 provinces were analyzed with 20 pairs of polymorphic simple sequence repeat (SSR) primers developed by our group. We aim to provide some theoretical basis for the conservation of R. molle. The results showed: (1) 314 alleles were amplified by 20 pairs of SSR primers, the average number of alleles of each SSR site was 15.700, and the mean values of polymorphic information content (PIC) and the effective alleles number (N_e) were 0.850 and 4.457, respectively. (2) The mean value of the genetic diversity index (H) and Shannon diversity index (I) of the seedling population of R. molle were 0.717 and 1.557, respectively. The genetic diversity of Jinxi (Jiangxi Province) population exhibits great level of variability, whereas the population of Panan (Zhejiang Province) exhibits the lowest level of variability. (3) Based on the analysis of the infinite allele model (IAM), it was found that the gene flow (N_m) and the genetic differentiation coefficient (F_st) of the seedling population of R. molle (F_st) were 1.372 and 0.155, respectively. AMOVA analysis showed that the probability of variation of the seedling population of R. molle mainly occurred in the middle population (86.0%), and the interpopulation variation was only 14%; (4) The results of neighbor joining (NJ) analysis and structure classification were basically similar, which are divided into 3 and 4 groups, respectively. Comprehensive comparative analysis found that the index parameters related to the genetic diversity of the seedling population of R. molle were all lower than the natural population of adults, which indicated that the fragmentation of habitat had posed a great threat to the survival of R. molle.

Abstract:To obtain the artificially induced 2n pollen from the diploid Chinese ancient rose ‘Old Blush’, which is to be used for the crossbreeding of modern rose and to effectively make use of its genetic resources, based on the understanding of the development of pollen mother cell of ‘Old Blush’, this study used the method of colchicine injection combined with wrapping to treat the tender buds, and we successfully obtained the 2n pollen which could be normally germinated. The performance of induced 2n pollen for cross breeding was also evaluated by observing the germination characteristics in vitro and on the pistil. The results showed that: (1) the colchicine absorbent cotton wrapping caused the death of part of the buds before the pollination, and the survival rate of flower bud decreased equally significantly with the increase of colchicine concentration and treatment time. (2) The 2n pollen induction rate differed significantly between the four colchicine concentrations of 2.5 g/L, 5.0 g/L, 7.5 g/L, and 10.0 g/L, but did not differ significantly between the three treatment periods of 24 h, 48 h, and 72 h. The best treatment was 24hour 5.0 g/L colchicine, which can produce 15.83% viable 2n pollen. The 2n pollen vitality of this treatment was 27.2% detected by Alexander staining. (3) The mother cell of ‘Old Blush’ pollen had abnormal lagging chromosomes and parallel spindle during meiosis. During the tetrad period, dyads and triads were formed whose number of chromosomes are doubled, and the 2n pollen was produced eventually. (4) The in vitro germination rate and pollen tube length of induced 2n pollen were insignificantly different from those of natural pollen, and both of them could germinate on the stigma of female parent and grow pollen tubes in the ovary, so they could be used for a further crossbreeding.

Abstract:The chromosomes of six species from Southwest China, consist of Prinsepia utilis, Potentilla parvifolia, Stellaria omeiensis, Psammosilene tunicoides, Cerastium pusillum and Eremurus chinensis were reported. Chromosome numbers and karyotypes of Ste. omeiensis were first reported in this study. The results were the following: (1) the karyotype formulas and asymmetry were respectively as: Pri. utilis 2n=2x=30=1M+20m+9sm, 2A; Pot. parvifolia 2n=2x=28=21m+7sm, 2B; Ste. omeiensis 2n=8x=72=1M+71m, 1B; There are ploidy changes in same population of Psa. tunicoides, the karyotype as: 2n=2x=14=14m, 1A and 2n=4x=28=28m, 1A. Cer. pusillum 2n=2x=24=24m(2sat), 1A. Ere. chinensis 2n=2x=14=2m+2sm+8st+2t, 4B. (2) Based on these data, the taxonomic and systematic significance of chromosome karyotypes in these species are discussed. It is supported that Pri. utilis is Prinsepia of Prunoideae. The cell ploidy of Pot. parvifolia is mainly diploid or tetraploid. (3) In this study the octaploid of Ste. omeiensis, maximum chromosome number of Stellaria, was first reported. Comparing the chromosomal studies of the Psammosilene and the Silene, it was found that Psammosilene probably were generated by the common ancestor group through aneuploidy. In this study, the presence of 2n=24 chromosome number and a pair of satellites were firstly found in Cerastium pusillum. This study showed that E. chinensis may be dimorphic nucleus.

Abstract:In order to explore the response characteristics of strawberry flower organs to high temperature, low temperature and salt stress, we used strawberry variety ‘Sweet Charlie’ as the test material. 0 ℃, 4 ℃, 25 ℃ (CK), 37 ℃, 200 mmol/L NaCl, 400 mmol/L NaCl and other stress treatments were used to investigate the appearance, growth and development of flowering organs, antioxidant enzyme activities of flower organs, and the expression of three strawberry flower organ meristem genes, 12 genes of flowering pathways, and three antioxidants enzyme genes and six stressresistant genes. The results showed that: (1) 0 ℃, 4 ℃, 37 ℃, 200 mmol/L NaCl, 400 mmol/L NaCl treatment inhibited the opening of strawberry flowers, 0 ℃ low temperature significantly inhibited the opening of strawberry flower organs, and caused the flower organs of strawberries hurt. (2) When strawberry plants were exposed to high temperature, low temperature and salt stress, the activities of antioxidant enzymes SOD, POD, CAT and MDA content in flower organs were increased, and the expression levels of related antioxidant enzyme genes were also increased. (3) 0 ℃, 4 ℃, 37 ℃ and 200 mmol/L NaCl, 400 mmol/L NaCl solution significantly reduced the expression of FaAP1, FaLFY, FaFD, FaSOC1 and other flowering genes in strawberry flower organs; 0 ℃ low temperature induced the expression levels of four coldresistant genes such as FaICE, FaRD29A, FaCOR and FaAFP; salt stress of 200 mmol/L NaCl and 400 mmol/L NaCl significantly increased the expression of FaP5CS gene. Studies showed that 0 ℃, 4 ℃, 37 ℃, 200 mmol/L NaCl, 400 mmol/L NaCl solution inhibited the flowering process of strawberry and caused damage to strawberry flower organs. Different stress treatment significantly increased the SOD of strawberry flower organs. The activities of POD, CAT and MDA content, the expression of the corresponding antioxidant enzyme genes were upregulated, and the expression of genes involved in the flowering pathway of strawberry was significantly decreased, and the expression level of related stressresistant genes was enhanced.

Abstract:This study was conducted to explore the expression of the genes associated with anthocyanins biosynthesis and the differences of anthocyanins accumulation in the peel and pulp of one new redflesh grape, ‘Zhongshanhongyu’ (ZSHY). Highperformance liquid chromatography with mass spectrometry (HPLC/MS) and qRTPCR were used to understand the laws of anthocyanins accumulation and related genes expression during the berry development. It aims to provide a theoretical basis for improving quality of grapes. The results showed that: (1) there are total 13 kinds of anthocyanins were detected from the peel and pulp of ‘Zhongshanhongyu’ and all of the anthocyanins were monoglucoside or monogalactoside. It is suggested that ‘ZSHY’ probably belong to the cultivar Vitis vinifera. (2) One of detected anthocyanis, Pelargonidin3Oglucoside barely contained in the cultivar V. vinifera was detected in the peel and pulp of our material. Besides, the composition and content of anthocyanins was also various in different tissues. In the peel of ‘Zhongshanhongyu’, the content of Delphinidinbased anthocyanins was significantly higher than Cyanidinbased anthocyanins, while the contents of Delphinidinbased and Cyanidinbased anthocyanins were almost same with each other. This result may due to the higher expression of F3′5′H in the peel of ‘Zhongshanhongyu’. In addition, the ratio of acylation anthocyanins was higher in the peel than in the pulp. (3) The regulation of the expression level of MYBA2 was consistent with UFGT, and UFGT barely expressed in the pulp, while MYBA2 maybe the key point that could regulate the pulp veraison. Besides, the expression of PYL1 which related to the regulation of ABA, also in according with the expression of OMT and LDOX.

Abstract:To explore the mechanism of variation in fruit coloring of peach (Amygdalus persica) in different tree canopy positions and its relationship with environmental factors, we studied the dynamic changes in temperature and light intensity in different canopy positions, i.e., upper, outer middle, inner middle and lower canopy during three fruit development stages like stone hardening stage, expanding stage and maturing stage of lateripening cultivar ‘Xiahui 8’ peach. The effects of environment on peel color, pigment content and the gene expression level related to fruit coloration were also studied. The results showed that： （1） the ripe fruits in upper and middle canopy (upper, outer middle and inner middle) of ‘Xiahui 8’ peach had significantly higher a^*/b^* (a^*, b^* are red and yellow saturation scale, respectively.) compared to the lower canopy fruit. （2） The ripe fruit in lower canopy had significantly lower Ant(anthocyanin) content and higher Chl(chlorophyll) in peel compared to the other fruits. （3） The expression levels of Ant biosynthetic related genes (UFGT, DFR, LDOX, CHS, F3H) revealed that all these five genes in peel were involved in Ant biosynthesis. （4） Before peel color changing, low light intensity could downregulate the expression level of the Ant biosynthetic related genes especially UFGT, DFR and CHS; While compared to the strong light environment, the expression levels of the related genes as mentioned above increased relatively under the weak light environment during fruit maturing stage. The results also suggested that the difference of light in different tree canopy positions might be one of the main environmental factors leading to fruit color difference.

Abstract:With the perennial cutting seedling of Euonymus laxiflorus, E. maackii and E. alatus as experimental materials, we determined the leaf color parameters and related physiological and biochemical indexes of the leaves during the color change period. The changing rules and internal relations of various indicators were discussed, with a prospect to provide a scientific basis for selecting excellent color leaf plants. The results showed that: (1) the values of L^*(Gloss brightness) and b^*(Yellow/Blue) of E. laxiflorus showed an upward trend, and the value of a^* (Red/Green) did not change much. The values of L^* and b^* of E. maackii increased first and then decreased and the value of a^* is on the rise. The values of L^* and b^* of E. alatus did not changed much and the value of a^* is on the rise. (2) The chlorophyll content of the 3 species showed a significant downward trend during the color change period. The relative content of anthocyanins and the value of anthocyanin / chlorophyll of E. laxiflorus were relatively stable while its value of carotenoid/chlorophyll increased. The relative content of anthocyanin and the value of anthocyanin/chlorophyll of E. maackii and E. alatus increased, and their value of carotenoid/chlorophyll remained stable. (3) The phenylalanine ammonia lyase (PAL) activity of the three species showed a downward trend, and the activity of chalcone isomerase (CHI) increased first and then decreased. The activities of peroxidase (POD) and polyphenol oxidase (PPO) of E. alatus remained stable. The POD of E. laxiflorus and E. maackii increased. The PPO of E. laxiflorus remained stable and the PPO of E. maackii showed a downward trend. (4) The mass fraction of soluble sugar and starch of E. laxiflorus and E. alatus increased first and then decreased. The mass fraction of soluble sugar and starch of E. maackii increased. (5) According to the correlation analysis, the yellow color of E. laxiflorus was mainly due to the decomposition of chlorophyll. The red color of E. maackii and E. alatus were mainly due to the synthesis of anthocyanins. Soluble sugar, starch, CHI had a certain effect on the synthesis of anthocyanins. POD promoted the appearance of red leaves. PAL and PPO had no significant relationship with the synthesis of anthocyanins.

Abstract:The relations among phenolics content, activities of enzymes related to phenolics metabolization and antioxidant activity in leaves of Juglans sigillata Dode. cv.‘Qianhe 7’were explored at different development periods. The results showed: (1) the phenolic acids and flavonoids were the most content compounds of phenolics, and four kinds of enzymes, namely DAPHS, PAL, C4H and 4CL play the important roles in the phenolics biosynthesis. While POD and PPO related decomposition were higher at leaf mature period, and the PPO is responsible for polyphenol oxidation. (2) With the development of leaves, the total polyphenol extract of the leaves showed a decreasing trend on the ABTS and DPPH free radical, while the reduction capacity of PFRAP and PFRAP increased continuously, reaching a peak in early August, and then remained at a high level. (3) With the development of leaves, phenolic acids were positively correlated to activities of PAL, C4H, the content of phenolic acids and flavonoids were strongly correlated to activities of DAPHS. Furthermore, the total contents of phenolic acids and flavonoids were negatively correlated to PPO. (4) The phenolic acids content was significant or extremely significant correlated to four kinds of antioxidant activity, the correlations between PAL, C4H, CHI and antioxidant activity were stronger than those of others EAB. The activities of PAL, C4H and CHI were positively correlated to IC₅₀ values of DPPH and ABTS⁺, and negatively correlated to values of FRAP and PFRAP. While the activities of PPO and POD were negatively correlated to IC₅₀ values of DPPH and ABTS⁺, and positively correlated to values of FRAP and PFRAP.

Abstract:We studied the effects of alternate respiration pathway on chlorophyll content and fluorescence characteristics of Angelica sinensis seedlings by pot experiment in greenhouse to explore the role of alternate respiratory pathway in the response of A. sinensis under low temperature (4 ℃ and -7 ℃). It was found that, with the decrease of temperature and the increase of low temperature time, the chlorophyll content, actual photochemical efficiency ［Y(Ⅱ)］, photosynthetic electron transfer rate (ETR), and photochemical quenching coefficient (qL) of A. sinensis decreased, while the nonphotochemical quenching coefficient (NPQ) was increased. Meanwhile, low temperature stress also resulted in a significant increase in the alternate respiratory capacity of the A. sinensis seedlings. Under low temperature stress, compared with the A. sinensis seedlings without chemical treatment, the chlorophyll content, Y(Ⅱ), ETR and qL of A. sinensis seedlings pretreated with the inhibitor of the alternate respiratory pathway ［1 mmol·L^-1 salicylhydroxamic acid (SHAM)］ decreased further, but NPQ increased significantly, and the lower the temperature was, the greater the range of rise and fall was. These results indicate that low temperature stress significantly inhibited the chlorophyll synthesis and photochemical properties in the leaves of A. sinensis seedlings, and the alternate respiratory pathway has protective effects on PSⅡ photochemistry and chlorophyll biosynthesis of A. sinensis seedlings under low temperature stress.

Abstract:Taking the Eriobotrya japonica ‘Baiyu’ of 24 orchards planted in the hillside area of Wuzhong district, Suzhou, Jiangsu province as the research object, we carried out the correlation analysis between soil, leaves and fruits mineral elements and their fruit quality indicators by using the typical correlation analysis method. Regression analysis was used to screen the main mineral elements in soil, leaves and fruits affecting the quality of loquat fruit and the main soil mineral nutrient factors affecting leaves mineral elements, which provide a theoretical reference for orchard nutrition management techniques to improve the quality of loquat fruit. The results showed that: (1) the quality index of loquat fruit was different between different orchards. (2) The quality of loquat fruit was mainly affected by the content of mineral elements in leaves and fruits. Among them, the weight of per fruit was significantly positively correlated with N content in leaves and negatively correlated with N content in fruits. The content of soluble solids was significantly positively correlated with the contents of N and Mg in leaves, and significantly positively correlated with the contents of P and Mn in fruits, and negatively correlated with the contents of Ca and Mg in fruits. The titratable acid content was significantly negatively correlated with the contents of N and Zn in the leaves, and negatively correlated with the contents of N and Mn in the fruits, and positively correlated with the content of Ca in the fruits. (3) The correlation between fruit quality index and soil mineral nutrient content is weak. Soil mineral nutrient mainly affects leaf mineral content, which indirectly affects fruit quality. Among them, P, K, Ca, Mn and Cu in soil have great influence on the contents of mineral elements in leaves. According to the study, the key technical approach of soil management in hillside orchard of Dongshan is to increase the contents of P, K, Zn and reduce the content of Ca in soil. The key measure to improve the quality of loquat fruit in Dongshan by increasing the content of N in leaves and the contents of N, P, Mn in fruits, and reducing the contents of Ca, Mg in the fruits.

Abstract:In order to provide a theoretical basis for a rotation between maizepeanut intercropping and wheatmaize multiple cropping, we studied the effects of maize intercropping peanut crops for rotation and phosphate fertilizer on tillering, leaf area index (LAI), dry matter accumulation, photosynthetic performance in flag leaves, and grain yield for winter wheat. A field experiment with three types of crops for rotation including sole maize, maizepeanut intercropping, and sole peanut, and two phosphate fertilizer levels including application 0 kg P₂O₅·hm^-2 (P₀) and 180 kg P₂O₅·hm^-2 (P₁) was conducted. Results showed that: (1) compared with maize crops for rotation, maizepeanut intercropping crops for rotation (intercropping crops for rotation) significantly increased the effective tillering numbers, LAI, net photosynthetic rate, and dry matter of winter wheat; The SPAD value, CO₂ saturation point, light saturation point, maximum net photosynthetic rate (P_nmax), AQY, carboxylation efficiency (CE), rubisco maximum carboxylation rate (V_cmax), maximum electron transfer rate (J_max) and triose phosphate utilization rate (V_TPU) of winter wheat flag leaves were also increased, CE, V_cmax and V_TPU enhanced to a significant level (P<0.05), and significantly improved (P<0.05) winter wheat grain yield and the composition. (2) Intercropping crops for rotation increased the P_nmax, AQY and CE in wheat flag leaves at milk stage, enhanced the kernels per spike, kernel weight and yield of winter wheat compared with peanut crops for rotation. (3) Supplying phosphate fertilizer with 180 kg P₂O₅·hm^-2 significantly improved winter wheat growth, and increased the SPAD value, P_nmax, AQY, CE, V_cmax, J_max, and V_TPU in flag leaves, and grain yield (P<0.05) in intercropping crops for rotation plots, compared with no phosphate fertilizer application. The study found that intercropping crops for rotation could effectively strengthen the apparent quantum efficiency and CO₂ carboxylation capacity in flag leaves of winter wheat, significantly enhance the photosynthetic capacity after flowering, and improve winter wheat growth. Thus, the kernels per spike, kernel weight and grain yield of winter wheat were increased, and intercropping crops for rotation combining with 180 kg P₂O₅·hm^-2 phosphate fertilizer could get more effective to winter wheat.

Abstract:Studying the effects of microorganisms on the decomposition of litter and its action law are great significance for revealing the changes of ecosystem material cycle and ecological function. In this study, the dominant lakeside plants Zizania latifolia and Hippuris vulgaris were used as the research objects from the Napahai wetland, which is located on the Northwestern Yunnan Plateau. The mass attenuation characteristics and changes in microbial carbon source utilization and metabolism of litter under different interfaces were studied by Biolog GenⅢ identification technology. The results revealed that: (1) after oneyear decomposition, the mass residue rates of Z. latifolia at air interface, water interface and soil interface were 77.7%, 42.2% and 25.3%, respectively, which were significantly higher than those of H. vulgaris (41.6%, 32.5%, 12.4%). For the same species, the mass residue rates at different decomposition habitats were air interface > water interface > soil interface. (2) There is a difference in the AWCD values of the two plants at different interfaces. The microbial carbon source has the highest metabolic intensity at the soil interface for Z. latifolia and the air interface for H. vulgaris. Microbial carbon source utilization of Z. latifolia was the highest under soil interface, and carbon source utilization of alcohols and amines reached 0.26 and 0.24, respectively. (3) There are certain differences in the microbial community structure between two plant litters. The microbial community at the soil interface of Z. latifolia litter has a strong ability to utilize all kinds of carbon sources, and its microbial community contains abundant species, and its community uniformity and diversity are more obvious, which is consistent with the seasonal variation of Z. latifolia mass residue rate. To study the relationship between the decomposition of litter and microorganisms can provide scientific basis and reference for the stability and development of ecosystem and the microbiological mechanism of litter decomposition.

Abstract:Taking the masson pine plantation 10a, 20a, 30a and 36a of mengguan forest farm in central Guizhou as the research object, by adopting the method of replacing time change with space change, we analyzed the dynamic characteristics of diameter scale structure and species diversity in the development process of masson pine plantation by setting 12 typical 20 m by 20 m plots. The results showed that: (1) the diameter grade structure of masson pine plantation was different at different age stages, with singlepeak structure at 10a stand and multipeak structure at 20a, 30a and 36a stands. (2) There are a total of 53 species in 53 genera and 35 families of plants under the forest, including 24 species in 24 genera and 16 families of shrubs, 29 species in 29 genera and 20 families of herbs, with relatively rich species. Species composition of stands of different ages: 20a stands > 10a stands > 30a stands > 36a stands. (3) Species richness index of masson pine firstly increased and then decreased with the increase of forest age. Shannnwiener index, Simpson index, Pielou evenness index and Alatalo evenness index showed the opposite trend between 10a and 30a, and the same trend between 30a and 36a.

Abstract:We analyzed the diversity of nitrogenfixable bacterium communities in the rhizosphere of larch in different periods in Arxan region by traditional bacterial isolation and culture combined with 16S rDNA sequence analysis, so as to reveal the diversity of nitrogenfixable bacteria in the rhizosphere of larch and the seasonal variation rules of the community structure, and to provide theoretical basis for the sustainable development of forest ecosystem. The results show the following: (1) From Arxan Larix gmelinii rhizosphere soil, a total of 112 bacterium strains, isolation and purification of points belonging to 14 genera of 41 species. They include Pseudomonas, Burkholderia, Rhizobium, Phyllobacterium, Arthrobacter, Paenibacillus, Serratia, Erwinia, Curtobacterium, Bacillus, Enterobacter, Acinetbacter, Caulobacter, and Rhodococcus. Pseudomonas dominated among the bacterial isolates, followed by Phyllobacterium, Burkholderia and Arthrobacter. (2) Seasonal changes had a significant effect on the change of nitrogenfixing flora of larch, which showed that the most dominant group in April and October was Pseudomonas from the γproteobacteria. The most dominant groups in June and August were the same,but the composition was different. Both of them were gamma proteobacteria and actinomycetes. In June, the dominant bacterium groups included Pseudomonas, Curtobacterium, Rhodococcus and Arthrobacter. In August, the dominant bacterium groups were Pseudomonas, Acinetbacter, Enterobacter, Curtobacterium, Rhodococcus and Arthrobacter. (3) Species evenness index (McIntosh index) varies significantly in different periods, with the largest in August and the smallest in April, and the variation range is between 0.83 and 1.164. The ShannonWiener index was significantly higher in June and August than in April and October. Dominance index, Simpson index in April and October is significantly higher than in June and August. The results showed that the rhizosphere microbial diversity of larch in Arxan area was relatively high, and the communities were relatively complex. Most of the 14 isolated genera were rhizotrophic bacteria, and the community composition of nitrogenfixing bacteria in different periods was significantly affected by seasons.

Abstract:Though systematic investigation, specimen collection, inspection, sorting and identification of the Oberonia Lindl. of Orchidaceae from Xizang Autonomous Region, China, five newly recorded species had been found, which are: Oberonia longibracteata Lindl., O. falconeri Hook. f., O. pyrulifera Lindl., O. jenkinsiana Griff. ex Lindl and O. anthropophora Lindl.. The morphological descriptions of the five plants are provided, and their voucher specimens are deposited in the herbarium of Research Institute of Xizang Plateau Ecology(XZE). At present, there are 14 species of Oberonia Lindl. in Xizang Autonomous Region, China. A key to species is prepared to identify the resources of Oberonia Lindl. and protect them effectively.

Abstract:A newly recorded mycoheterotrophic orchid, Gastrodia clausa T. C. Hsu, S. W. Chung & C. M. Kuo, is reported from Dinghushan National Nature Reserve in Guangdong, China and the vouchers are kept in the herbaria of South China Botanical Garden, Chinese Academy of Sciences (IBSC). It is distinguished by the short enclosed or hardly opening perianth tube and peloric flower with a small, petaloid lip conjoint with the perianth tube and a prominent ventral appendage of column. Detail morphological descriptions, colour plate and taxonomic notes on the species are provided.

Abstract:New records of wood species, Calophyllum membranaceum Gardn. & Champ. and Uvaria boniana Finet & Gagnep., were reported in the paper according to the native vegetation survey in the Fujian Province from 2017-2018. C. membranaceum is the newly recorded genus belonged to Calophyllum, Calophyllaceae and U. boniana, which belonged to Uvaris of Annonaceae, is the newly recorded species in the Fujian Province. Brief morphological descriptions and photos of these species were provided and the findings have enriched the wood species resource in Fujian Province. Specimens were deposited in the herbarium of Fujian Agriculture and Forestry University.

Abstract:One of the most important functions of plant roots is to uptake nutrients from the soil and upwards them to the aerial parts. Water and nutrients are transported across epidermis, cortex and endodermis of the concentric root cell layers before reaching the central vasculature for aboveground metabolism. The endodermis undergoes two stages of differentiation with forming two diffusion barriers, Casparian strips and suberin lamellae, which play important roles in controlling nutrients acquisition and loss. This review summarizes the research progress of endodermal differentiation and barrier function in the past few years, and put forward the future research directions, so as to provide a theoretical basis for the further exploring the role of endodermal barrier in plant growth and development, as well as stress adaptation, and opens up a new thought for plant breeding in turn.