Stems of Populus simonii×P. nigra ‘Baicheng’ in vitro plants were selected as explants and MS medium was used to establish tissue culture system by adjusting the hormone concentrations of 6-BA， NAA， TDZ and IBA. Based on the tissue culture system， the optimal concentration of kanamycin and infection time were confirmed to establish Agrobacterium tumefaciens-mediated genetic transformation system for P. simonii×P. nigra ‘Baicheng’. By using this system， the transgenic plants overexpressed a key tension wood formation regulator LBD39 （Lateral Organ Boundaries Domain） were created successfully. The results showed that the tissue culture system consisted of three stages， including adventitious bud differentiation induction （MS+ 0.5 mg·L^-1 6-BA+0.1 mg·L^-1 NAA+0.001 mg·L^-1 TDZ， shoot differentiation rate=92.6%）， stem induction （MS+0.2 mg·L^-1 6-BA+0.05 mg·L^-1 NAA， multiplication coefficient=6.5） and rooting induction （1/2 MS+0.4 mg·L^-1 IBA， rooting percentage=100%）. The optimal kanamycin concentration for genetic transformation was 30 mg·L^-1 and the optimal infection time was 20 min， and the transgenic plants were obtained successfully after 30 d of adventitious bud differentiation induction， 15-30 d of stem induction and 25 d of rooting induction with 2% transformation efficiency respectively. By using this system， five overexpressed plants of LBD39 were obtained， and the transformation efficiency was 3.3%.

In order to investigate the effects of saline-alkali stress on the plant growth， seedling of Heucheramicrantha ‘Silver Fan’ was used as materials， and 30， 60， 90， 120 and 150 mmol·L^-1 NaCl and NaHCO₃， and 20， 30， 40， 50 and 60 mmol·L^-1 Na₂CO₃， were used to simulate salt stress， salt alkali stress， and alkali stress， respectively. The experiment used 1/4 Hoagland nutrient solution as the control， and used water culture method to treat seedlings for 0， 7 and 14 d. The response of plants was observed from aspects such as salt damage rate and physiological indicators， and the effects of salt stress on the growth of ‘Silver Fan’ seedlings were analyzed and evaluated by principal component analysis of 7 indicators. The results showed that under different salt alkali stress treatments， the relative conductivity and malondialdehyde content（MDA） of the seedlings showed an increasing trend with time and concentration. The seedlings treated with 30 mmol·L^-1 NaCl or NaHCO₃ showed no obvious symptoms of salt damage， and all physiological indicators showed an upward trend with the prolongation of treatment time； With the increase of concentration and stress time， the salt damage index of seedlings increased， but the ornamental value decreased. The overall trend of superoxide dismutase（SOD） increased first and then decreased， reaching the maximum value at 90 mmol·L^-1 NaCl and 60 mmol·L^-1 NaHCO₃， respectively. Under the same stress time， the contents of chlorophyll（Chl）， chlorophyll a（Chla）， and chlorophyll b（Chlb） decreased continuously， while ρ（Chla）/ρ（Chlb） increased with the increase of stress concentration. Under different concentrations of Na₂CO₃ stress， the SOD activity generally showed an upward trend， reaching the maximum value at 50 mmol·L^-1， and the contents of Chl， Chla， and Chlb generally showed a downward trend. However， under the same time conditions of stress， ρ（Chla）/ρ（Chlb） decreased first and then increased with the concentration increasing， and the ratio of ρ（Chla）/ρ（Chlb） was the smallest under 40 mmol·L^-1 treatment. In general， ‘Silver Fan’ seedlings had a certain salt alkali resistance ability， and could grow at NaCl concentration<90 mmol·L^-1， NaHCO₃ concentration<60 mmol·L^-1， and Na₂CO₃ concentration< 40 mmol·L^-1， and had certain ornamental value， respectively. The results of principal component analysis showed that the relative conductivity， Chla， and Chlb contents could be used as indicators for evaluating the salt alkali resistance of the ‘Silver Fan’.

Plant development is highly plastic. As ambient temperature increased， plant stems and petioles elongated， and promoted leaf surface cooling， the process known as thermomorphogenesis. High temperatures also triggered root elongation， which named as root thermomorphogenesis. There were many studies on the regulation of plant shoot thermomorphogenesis， but few investigations on the regulatory mechanisms of plant root thermomorphogenesis. In this review， we summarized the recent progresses in the field of plant root thermomorphogenesis， and proposed future research directions.

To investigate the role of WRKY transcription factors（TFs） in sensing saline-alkali stress signals and maintaining their tolerance function through physiological and biochemical regulatory pathways， and the WRKY42 gene of Amorpha fruticosa was cloned and the expression pattern in response to salt（NaCl） and alkali（NaHCO₃） stress and tissue organs was analyzed， and the salinity tolerance function was also studied its by overexpression in tobacco. In this study， the AfWRKY42 gene was cloned based on transcriptome sequencing data of A. fruticosa L. under stress. Bioinformatics analysis showed that AfWRKY42 contained a WRKY structural domain， two low-complexity regions and a helix region. Phylogenetic tree analysis of amino acids revealed that AfWRKY42 was most closely related to WRKY47 of Cajanus cajan and WRKY42 of Mucuna pruriens. The localization of AfWRKY42 protein in mesophyll protoplasts of Arabidopsis thaliana was confirmed in nucleus by a transient gene expression system. Quantitative analysis of AfWRKY42 gene showed the highest expression in the shoot epidermis of Sophora japonica. Detection of expression patterns in roots and leaves treated with NaCl and NaHCO₃ showed an overall increasing trend induced by it， suggesting that overall stress induced an increase in AfWRKY42 gene expression， and AfWRKY42 gene was associated with the regulation of salinity tolerance in plants. Analysis of salinity tolerance in 35S-initiated overexpressing T3 generation of tobacco lines transgenic for AfWRKY42 gene showed that the transgenic tobacco lines showed increased resistance after salinity stress treatment， it had higher chlorophyll and electrical conductivity and significantly lower malondialdehyde content than the wild type， indicating that AfWRKY42 played an important regulatory role in response to salinity stress. It would provide a WRKY transcription factor candidate gene for salinity resistance breeding and lay the foundation for improving the resistance of A. fruticosa and other plants.

In order to explore the law of flower color change of Hibiscussyriacus during the flowering process and the influence of physical and chemical factors such as pH， metal ions and water content on its flower color， the composition and physicochemical factors of anthocyanins in the petals of H. syriacus ‘Qiansiban’ and ‘White Chiffon’ at different blossoming periods were studied respectively by the color chromato-meter， ion emission spectrometer and high performance liquid chromatography-mass spectrometry. The results showed that： （1）In terms of the composition of anthocyanins， 10 kinds of flavonoids such as Quercetin-3-glucoside， Luteolin-7-O-glucoside， and Santolol-7-O-glucoside were detected and identified in the petals of the two varieties， and 5 kinds of anthocyanins such as Mallorin-3-O-glucoside were detected and identified in the H. syriacus ‘Qiansiban’， and no anthocyanins were detected in the H. syriacus ‘White Chiffon’. （2）In the process of blossoming， the brightness of the flower color increased， the color degree decreased， and the color changed from purplish red to lavender， and light yellow to white respectively. During the blossoming， the composition of anthocyanins remained unchanged， and the content of anthocyanins and total anthocyanins gradually decreased in H. syriacus ‘Qiansiban’. （3）The pH of petals in H. syriacus ‘Qiansiban’ and ‘White Chiffon’ were both acidic， and the activities of Peroxidase（POD） and Polyphenol oxidase（PPO） showed significant difference in different periods. Among them， POD activity in H. syriacus ‘Qiansiban’ was higher than that in H. syriacus ‘White Chiffon’， while PPO activity was the opposite； calcium and magnesium ions were the highest content of metal ions in H. syriacus petals， while copper， iron， manganese， zinc and other metal ions had low content in H. syriacus petals. （4）In terms of correlation analysis， during the blossoming of H. syriacus ‘Qiansiban’， the color degree C* was significantly positively correlated with hue a*， and significantly positively correlated with calcium ion， iron ion and manganese ion respectively； during the blossoming of H. syriacus ‘White Chiffon’， the color degree C* was significantly positively correlated with hue b* and PPO activity， and negatively correlated with hue a* respectively. The research showed that the anthocyanins were the material basis of flower color change of H. syriacus flower petals. Besides anthocyanin content， the flower color change process was also closely related to the content of calcium， iron， manganese and other metal ions. PPO activity was a potential biochemical factor to promote the degradation of flavonoids in white flower varieties.

In order to explore the role of WALLS ARE THIN（WAT1） in wood formation and response to stress in woody plants， bioinformatics toolswas used for analysis， and quantitative Real-time PCR（qRT-PCR） was used to investigate the expression patterns of EgrWAT1L and EgrWAT1S in different tissues， internodes and in response to different stresses， and the gene EgrWAT1S and its other transcript EgrWAT1L were cloned from Eucalyptus grandis. The results showed that the EgrWAT1S was highly expressed in phloem， while EgrWAT1L was mainly expressed in roots， and the expression patterns were significantly different under methyl jasmonate（MeJA） and salicylic acid（SA） treatment， salt stress， phosphorus（P） and boron（B） deficiency， and even opposite under MeJA and SA. These results suggested that EgrWAT1L might affect EgrWAT1S expression through transcriptional regulation and further protein translation in response to hormone and stress treatments. The studies provided a basis for further elucidate the function in the growth and development of EgrWAT1 gene and also provided a possibility for future molecular breeding of Eucalyptus.

In order to promote the rapid greening of the steep bare rock slopes in the Jiuzhaigou National Nature Reserve after the earthquake， and accelerate the ecological restoration process of the landscape， based on references and field investigations， 30 common native mosses in the region were selected， and an evaluation index system of 18 items was constructed based on six aspects including resistance ability， availability， ecological function， reproductive ability， biomass accumulation， and aesthetic appeal， using the Analytic Hierarchy Process（AHP）. The results indicated that： according to the comprehensive evaluation score， the mosses were divided into four grades. Finally， five species， Racomitrium japonicum， Hypnum plumaeforme， Eurohypnum leptothollum， Plagiomnium ellipticum and Brachythecium rutabulum were selected. The results should provide an objective guidance for future ecological restoration without soil in Jiuzhaigou and its surrounding cold fragile ecosystem area.

To provide an effective supplement for ecological restoration technology in the Arsenic sandstone area， the microecological soil environment in Pinus tabulaeformis and Caragana korshinskii plantation， naturally restored grassland， and abandoned land were studied respectively. The changes in microbial community structure and microbial biomass carbon， nitrogen and phosphorus contents， soil enzyme activities related to nutrient conversion， and soil chemical properties were analyzed in different vegetation types. The correlation between soil microbial community structure and soil microecological environment was discussed， then the main influencing factors of soil microhabitat types were explored in different ecological restoration vegetation. The results showed that： （1）The soil dissolved organic carbon（C） content of P. tabulaeformis plantation was the highest of the four vegetation types， which was 4.26 mg·kg^-1. The soil available nitrogen（N） content of the C. korshinskii plantation was the highest， which was 11.69 mg·kg^-1. However， there was no significant difference in soil available phosphorus（P） content among P. tabulaeformis plantation， C. korshinskii plantation and natural restored grassland. （2）The enzyme activities related to nutrient conversion and soil microbial biomass C， N and P of P. tabulaeformis plantation were significantly higher than those of other vegetation types. （3）The relative abundance of soil fungi was the highest in P. tabulaeformis plantation， which was 31.36%. The relative abundance of Gram-positive bacteria in the soil of the C. korshinskii plantation and abandoned land was the highest， which were 35.73% and 37.27%. The relative abundance of soil Gram-negative bacteria increased with the decrease of available organic C. It was the lowest in P. tabulaeformis plantation（36.82%） and the highest in the natural restored grassland（42.13%）. （4）The relative abundance of soil fungi was positively correlated with enzyme activities related to nutrient conversion. Gram-negative bacteria of preferred unstable C sources were less correlated with soil microecological environmental factors. Still， Gram-positive bacteria were significantly negatively correlated with the indexes of soil C conversion. （5）The Redundancy analysis showed that alkaline phosphatase was the most explainable environmental factor， and it was positively correlated with fungi and negatively correlated with Gram-positive bacteria（P<0.01）. In conclusion， the stability of the microecological environment of P. tabulaeformis plantation was relatively high in the ecological restoration vegetation types of the Arsenic sandstone area， which might be used as the optimal ecological restoration tree species in the Arsenic sandstone area. The synergistic effect of alkaline phosphatase and fungi in rhizosphere soil microecological environment might effectively regulate environmental restoration in Arsenic sandstone areas.

Rare and endangered plants are important plant resources in nature， and play a key role in the study of plant phylogeny， ecosystem restoration， plant stress resistance physiology， and the excavation of stress-resistance genes. However， the lack of genetic information has severely restricted the conservation and utilization in most endangered plant. Due to the large genomes， complex genetic information， and unclear genetic backgrounds of endangered plants， it is relatively difficult to sequence the genomes of endangered plants. In recent years， RNA-Sequencing could directly sequence non-reference genomic species， what makes it to be widely used in the study of endangeredplants. In addition， this paper presented the prospect of the application of RNA-Sequencing technology in the study of endangered plants and suggested the new ideas of transcriptome using in the endangered plants in future.

To explore the effect of tree age of ancient Platycladus orientalis on rooting of cuttings propagated from them and the physiological mechanism during the cutting process， the cuttings of 5， 100， 300 and 700 years P. orientalis female trees were used as scions respectively， and the phloem at the base of the cutting at rooting stages［0 d （S1， stage of before cutting）， 35 d（S2， stage of callus formation）， 65 d（S3， stage of adventitious root formation）， 95 d（S4， stage of adventitious root elongation）］ were harvested as the materials and the dynamic changes in the physiological indicators were measured， and the rooting rates and the numbers of rooted cuttings were counted respectively. The results showed that both of the rooting rates and the numbers of rooted cuttings propagated from ancient P. orientalis were significantly less than those of five years ones（P<0.05）. The nutrients（total sugar and total protein）， activities of antioxidative enzymes（polyphenol oxidase（PPO），peroxidase（POD）， superoxide dismutase（SOD）） and hormones（Indole-3-acetic acid（IAA）， zeatin riboside（ZR）） contents of the cuttings of five years donors were significantly more than those of ancient P. orientalis donors at all rooting stages， indicating that the high levels of these substances facilitated the rooting of the cuttings（P<0.05）. The contents of malondialdehyde（MDA）， abscisic acid（ABA）， and gibberellin（GA） showed a significant increase with increasing tree ages， indicating that the cuttings of ancient P. orientalis contained more harmful substances and hormones that inhibited rooting（P<0.05）. The nutrients（total sugar and total protein） and hormone（IAA and GA） contents showed a trend increased first and then decreased throughout the four stages， and it was worth noting that the contents reached maximum value at S3. On the contrary， ABA contents at S3 were significantly lower than that of another three stages（P<0.05）. The results indicated that the stage of adventitious root formation（S3） was a critical stage during the cutting process（P<0.05）. The larger the ratio of ω（IAA）/ω（ABA） and ω（ZR）/ω（ABA） were， the better for adventitious root formation. Tree ages significantly affected the rooting rate of P. orientalis cuttings， but there was no significant difference in the rooting rate of cuttings of ancient P. orientalis of different ages. Therefore， the reasons for difficulties in rooting of cuttings from ancient P. orientalis were mainly attributable to the lack of nutrients（total sugar and total protein）， activities of antioxidative enzymes（PPO， POD， and SOD） and endogenous hormones（IAA and ZR） beneficial to rooting.

The polysaccharides of Schisandra chinensis were extracted by ultrasonic-assisted cellulase enzymolysis from the dried fruit of S. chinensis as raw material， and the extraction process and anti-oxidative stress activity of S. chinensis polysaccharides were studied. Using polysaccharide yield as index， single factor experiment and Box-Behnken response surface test were used to investigate the effects of enzyme concentration， ultrasonic power， extraction time and solid-liquid ratio on polysaccharide yield of S. chinensis， and the ultrasonic-assisted enzymatic extraction process was optimized. A lipopolysaccharide（LPS） induced oxidative stress damage model of HepG2 cells was established， and the levels of malondialdehyde（MDA）， superoxide dismutase（SOD） and reactive oxygen species（ROS） were used as indicators， and the anti-oxidative stress ability of S. chinensis polysaccharides was investigated. The results showed that the optimal extraction conditions as followed： the enzyme concentration was 1 420 U·g^-1， the ultrasonic power was 500 W， the extraction time was 46 min， the solid-liquid ratio was 1 g∶32 mL. Under these conditions， the yield of polysaccharides was 22.25%. Moreover， the extracted S. chinensis polysaccharides might improve the SOD level in the LPS-induced HepG2 cells， but reduce the MDA accumulation and ROS fluorescence intensity in the cells， and effectively relieve the LPS-induced oxidative stress in HepG2 cells. The extraction conditions of polysaccharides from S. chinensis were optimized， and it was found that the extracted polysaccharides had good antioxidant stress ability.

To investigate the physiological adaptability of mangrove plants under different salinity， the influences of different salinity（0， 5%， 10%， 15%， 20%， 25%， 30%， 35%） on the growth of six mangrove species（Bruguiera gymnorhiza， Ceriops tagal， Rhizophora stylosa， Bruguiera sexangula， Aegiceras corniculatum， Kandelia obovata） were assayed， and the morphological and physiological characteristics of six species were determined respectively， including the biomass， plant height increment， base diameter increment， net photosynthetic rate， chlorophyll a content， chlorophyll b content， total chlorophyll content， superoxide dismutase（SOD） activity， proline（Pro） content and malondialdehyde（MDA） content. The results showed that the 5%-20% was suitable salinity for the growth of six mangrove seedlings， and the Parmentiera cerifera had high salt tolerance. The SOD activity， Pro content and MDA content and chlorophyll content of six mangrove seedlings increased， but net photosynthetic rate and growth rate decreased under salt stress. The results showed that the photosynthesis of the six species seedlings decreased under salt stress， the photosynthetic rate increased by increasing the chlorophyll content， and the plant stress resistance might be improved by increasing the SOD activity， Pro content and MDA content in the leaves.

To provide theoretical basis for genetic improvement of reproductive regulatory traits of Catalpa bungei， DELLAs family genes were identified and the function of CbuGRAS9 was analyzed. Based on the genomic data of Catalpa bungei， five CbuDELLAs genes homologous to Arabidopsis thaliana were identified and cloned. ExPASy， SWISS-MODEL， Plant-mPloc， PlantCare and other online tools were used to predict the isoelectric point， protein structure， sub-cellular localization and promoter cis-acting elements of CbuDELLAs protein. The expression differences of CbuDELLAs were analyzed by using Catalpa ‘Bairihua’ and Catalpa bungei ‘Luoqiu No.1’ as materials， and the molecular function of CbuGRAS9 was confirmed by heterologus transformation in Arabidopsis thaliana， and the proteins interacted with CbuGRAS9 were screened by yeast two-hybrid library. The results showed that the amino acid number of the five CbuDELLAs proteins ranged from 455 to 588 aa， the relative molecular weight of the proteins ranged from 5.04 to 6.43 kDa， and the isoelectric point value ranged from 4.81 to 5.14. All CbuDELLAs proteins contained DELLA and GRAS conserved domains and are hydrophilic proteins. Sub-cellular localization prediction showed that CbuDELLAs protein was located in the nucleus. The analysis of promoter cis-acting elements showed that the five promoter regions of DELLAs all contained cis-acting elements involved in gibberellin reaction. The results of qRT-PCR showed that the expression of CbuDELLAs in Catalpa ‘Bairihua’ were significantly higher than that in Catalpa bungei ‘Luoqiu No.1’， and CbuGRAS9 was the most significantly gene， and the flowering time of CbuGRAS9 transgenic plants were significantly delayed. Proteins interacted with CbuGRAS9 were mainly concentrated in metabolic pathways such as ribosome， amino acid synthesis， secondary metabolism， photosynthesis and TCA cycle.

To explore the potential suitable distribution and ecological adaptability of Rhodiola tangutica on the Qinghai-Xizang Plateau， based on 38 distribution sites of Rhodiola tangutica across the plateau and seven environmental factors across current and future five periods， a relationship model between the distribution of Rhodiola tangutica and environmental factors was constructed using the MaxEnt model. The potential geographical distribution patterns for the current period（1970-2000） and four future periods（2030s， 2050s， 2070s and 2090s） under the SSP245 scenario were simulated and verified. The findings revealed that： （1）Altitude（Alt） and precipitation of the driest month（Bio14） were the most important ecological factors influencing the geographical distribution of Rhodiola tangutica， contributing rates of 89.3% and 4.9%， respectively. （2）under the current climatic context， the total suitable distribution area of Rhodiola tangutica on the Qinghai-Xizang Plateau was approximately 195.21×10⁴ km²， predominantly situated in the southern and northeastern parts of Qinghai， northwestern Sichuan， and central Xizang. （3）compared with the current period， the total suitable distribution area of Rhodiola tangutica in the next four periods would not change obviously； however， the area of high suitability would increase， with a tendency of concentrated distribution to the central Qinghai-Xizang Plateau.

The correct scientific name is the only international name of a species， which could reduce ambiguity in communication， but it would cause confusion in research and production if it is used incorrectly. As a hotspot plant Family， there were some problems of changes in scientific names in Gesneriaceae. Since the publication of Stauranthera grandifolia Benth.， different forms of the epithet， grandifolia and grandiflora， were used in various literatures. By checking related literatures， this paper confirms that the correct epithet should be grandifolia according to the Articles of the International Code of Nomenclature for Algae， Fungi， and Plants.

To explore the function roles of K⁺-efflux-antiporters KEA1 and KEA2 in Arabidopsis thaliana， wild type and kea1kea2 knock-down mutants of Arabidopsis thaliana were used as materials to investigate the effects of KEA1 and KEA2 on plant growth and development. Phenotypic analysis， propidium iodide staining to observe the structure of roots， high performance liquid chromatography to determine endogenous sugar content， transcriptome sequencing and qRT-PCR to analyze the relative expression levels of related genes， histochemical staining to detect the distribution of superoxide anion in leaves were performed respectively. The results showed that the root length of the kea1kea2 mutant was significantly shorter than that of the wild-type Col-0 plant in the absence of sucrose. Further observation showed that compared with the wild-type， the root meristem zone of kea1kea2 mutant was shorter， the endogenous sucrose content was decreased， and more O₂^·- was distributed in the leaves of the kea1kea2 mutant. However，when 30 g·L^-1 sucrose was exogenously added， there was no significant difference in root length between the wild-type and kea1kea2 mutant. Transcriptome analysis revealed that the expression of many key genes involved in sucrose signals and root growth were repressed in the kea1kea2 mutant. In summary， the results suggested that sucrose might affect AtKEA1and AtKEA2 to regulate root growth in Arabidopsis seedlings.

To clarify the function of FmCCoAOMT gene， the expression pattern of FmCCoAOMT gene was analyzed by qRT-PCR using Fraxinus mandshurica as material in this study. The results showed that FmCCoAOMT gene was tissue specific. The expression level was the highest in the xylem of both female and male perennial plants， and was 9.4 times higher than that in the bark of new shoots in male plants， and was 13.1 times higher than that of leaf in female plants. The leaf disk method was used to obtain transgenic tobacco plants. Compared with the wild type， the lignin content of overexpressing FmCCoAOMT was increased by 41%， while the cellulose and hemicellulose contents were decreased by 32% and 52%， respectively. Tobacco overexpressing FmCCoAOMT after abiotic stress treatment compared to wild type， the activity of POD and SOD increased， the content of MDA decreased， and the content of reactive oxygen decreased after stress treatment. After NaCl treatment， POD activity was 83% higher than that of control group. After NaCl， ABA and mannitol treatments， SOD activity increased by 56.6%， 44.2% and 19.0%， and MDA content decreased by 77.2%， 11.7% and 47.6%， respectively. The results indicated that FmCCoAOMT gene might be involved in lignin synthesis of F. mandshurica， promoted abiotic stress tolerance.

To explore the effects of exogenous salicylic acid（SA）added on plants， the physiological indices including membrane lipid peroxidation， reactive oxygen species accumulation， antioxidant enzyme activities， and antioxidant contents as well as gene expression in the leaves of Davidia involucrata seedlings under salt stress were investigated respectively. The results revealed that， under salt stress， the application of SA significantly reduced the relative electrolyte leakage， and inhibited the accumulation of malondialdehyde（MDA）and ROS， and increased the relative water content， activities of antioxidant enzymes（i.e.， SOD， POD， and APX）， and glutathione（GSH）contents. Moreover， treatment with SA resulted in differential expression of 2 581 genes（1 516 up-regulated and 1 065 down-regulated） under salt stress. KEGG analysis indicated that differentially expressed genes（DEGs）were enriched in nine pathways including phenylpropanoid biosynthesis. In addition， transcriptome sequencing and quantitative real-time PCR（qRT-PCR）results showed that exogenous SA significantly induced the expression of transcription factor genes including DiWRKY40， DiNAC25， DiMYB4， and DiMYB86 under salt stress. These results suggested that exogenous SA might stimulate stress responses in salt-treated D. involucrata seedlings and trigger variation in gene expression， resulting in alleviation of salt injury in D. involucrata seedlings.

In order to explore the effects of nitrogen addition on the growth and non-structural carbohydrate（NSC） content of Cinnamomum bodinieri seedlings in rare earth mine tailings， one-year-old C.bodinieri cuttings were used as materials， and calcium ammonium nitrate was used as nitrogen fertilizer（containing N 15%）， and three nitrogen levels（CK（0）， N1（1.8 g per plant）， N2（3.6 g per plant）） were set up to analyze the differences in root growth， biomass distribution and NSC of C.bodinieri seedlings under three nitrogen addition levels， and to explore the response of C.bodinieri in rare earth tailings to nitrogen addition. The results showed that： Nitrogen addition increased the biomass accumulation of different tissues of C.bodinieri seedlings in rare earth tailings， and the leaf biomass and canopy biomass at N1 level were significantly increased by 44.75% and 57.43%（P<0.05）， respectively， compared with N2. Compared with CK and N1 treatment， the leaf mass ratio of N2 level was significantly increased by 123.53% and 15.85%（P<0.05）， respectively. Nitrogen addition significantly promoted the root length and root surface area of both coarse roots（diameter>2mm） and fine roots（diameter≤2mm）（P<0.05）， and the promotion effect of N1 treatment was the most significant（P<0.05）. The specific root length and specific surface area under N2 treatment were higher than those of CK and N1， and significantly different from CK（P<0.05）. For NSC， N1 treatment increased the soluble sugar mass fraction in leaves and stems， while the NSC mass fraction of fine roots under N2 treatment was significantly lower than that of CK and N1 by 46.49% and 28.61%， respectively. In summary， during vegetation restoration in rare earth mine tailings， 1.8 g per plant calcium ammonium nitrate fertilizer might be suitable for fertilization management of C.bodinieri seedlings.

To investigate the potential function of ubiquitin carboxyl terminal hydrolases（UCHs） in the ubiquitination process of laticiferous of Hevea brasiliensis， the full-length sequences of two UCHs family members（HbUCH-L3 and HbUCH-L5） were isolated from Hevea brasiliensis， and both had typical UCHs domains. The open reading frame of HbUCH-L3 and HbUCH-L5 were 993 bp and 558 bp， and encoded 330 and 185 amino acids， respectively. The results of qRT-PCR showed that HbUCH-L3 and HbUCH-L5 were constitutively expressed in all tissues， but was low in latex. In vitro ubiquitination substrates cleavage of recombinant HbUCHs showed that both HbUCH-L3 and HbUCH-L5 had the function of hydrolyzing ubiquitin. HbUCHs significantly reduced the overall ubiquitination level of C-serum proteins； while， the deubiquitinating activity of HbUCH-L3 was higher than that of HbUCH-L5. Therefore， it was speculated that UCHs played a role in maintaining the dynamic balance of laticiferous ubiquitination and thus played a specific biological function， but the exact mechanism was still unclear.