Spatial transcriptomics（ST） is a technique used to resolve RNA-seq data at the spatial level， thereby resolving all mRNA in a single tissue section. The orderly attachment of spatial barcoding oligo（dT） primers to the surface of microscope slides makes it possible to encode and obtain positional information during mRNA sample processing and subsequent sequencing. Compared with the traditional transcriptome technology， the spatial transcriptome technology can obtain the true gene expression characteristics of cells in the in-situ environment of tissues and the relationship with the microenvironment， and provide high-precision and high-resolution in-situ spatial information for gene expression. In recent years， the development of spatial transcriptome technology has made significant progress. The detected cell flow， the quantity and quality of transcripts are continuously improved， and spatial location information is more accurate and comprehensive. It has been studied in Arabidopsis thaliana， Oryza sativa， and Populus， etc. In this paper， the successful applications of spatial transcriptome technology in the study of plant dynamic development trajectory， the analysis of differences between different tissues and cell types， and decoding of the interaction between plants and microbial communities were described. The problems and challenges of space transcriptome sequencing technology in plant research were discussed， and the great potential of space transcriptome technology in plant research was revealed， which provided a new perspective for further research and application in related fields.

Pipecolic acid（Pip） is a heterocyclic non-protein amino acid serving as precursor for the biosynthesis of biological metabolites. Structurally， the six-membered cyclic motif consists of five carbons and one nitrogen atom. Pip is a cyclic amino acid derived from lysine， in recent years， it has attracted attention in plant research. This review summarized the discovery， biosynthesis， biological functions， and action mechanisms of pipecolic acid， as well as its applications in agricultural production， and put forward prospects for future research directions aiming to establish a foundation for the potential application.

The response of soil microbial community functions to land use changes is of key importance in the prediction of soil ecological functions. In order to clarify the effects of different land use patterns on bacterial communities in the black soil region， the soil bacterial community structure， co-occurrence network structure and functional genes in cropland， forest land and grassland in the northeastern black soil region were analyzed， respectively， and the interaction mechanisms among land use patterns， soil physicochemical properties， bacterial diversity， bacterial community structure， co-occurrence network and functional genes were explored using structural equation modelling. The results showed that there were significant differences（P<0.05） in soil physical and chemical properties and bacterial community structure among different land use patterns， and that the Shannon index and the average degree of co-occurrence network of forest land and grassland were significantly higher than that in cropland（P<0.05）. The proportion of positive correlation edges of bacterial co-occurrence network in forest land was higher than that in other treatments， there was a stronger synergistic effect between soil bacteria in forest land. Functional gene results showed that different land use patterns significantly altered functional gene abundance（P<0.05）. Structural equation modelling indicated that bacterial community structure had the greatest direct effect on functional genes， and land use practices had the greatest indirect effect on functional genes. In conclusion， this study further confirmed the effects of different land use patterns on bacterial communities， which provided a scientific basis for land management in the black soil area.

Grassland is one of the most important land types in Daqing， and it is of great significance to grasp the spatial and temporal dynamics of grassland biomass to understand the carbon sink potential of Daqing. The remote sensing inversion model of aboveground grass biomass in Daqing was constructed by using MODIS-NDVI remote sensing data and aboveground grass biomass measured data and regression analysis. Trend analysis and correlation analysis were used to clarify the spatial and temporal distribution pattern of aboveground biomass and its relationship with major climate factors（precipitation and temperature） in Daqing over the past 20 years. The results showed that the exponential function inversion model constructed by using normalized difference vegetation index（NDVI） had the best interpretation of the aboveground biomass of grassland in Daqing， and the coefficient of determination R² was 0.77 and the root mean square error （RMSE） was 38 g⋅m^-2. The grassland biomass in Daqing urban areas showed a trend of fluctuating increase from 2000 to 2023， and reached a maximum value of 314 g⋅m^-2 in 2019； the aboveground biomass of grassland in most areas showed a significant increasing trend， with a maximum value of 423 g⋅m^-2 and an average value of 280 g⋅m^-2， and its spatial characteristics showed a gradually increasing distribution pattern from southeast to northwest， with concentration in the north and dispersion in the south. Precipitation had a significant effect on biomass（r=0.584， P<0.05）， but the monthly mean temperature had no significant effect on biomass. The above results might provide a strong theoretical basis and data support for the scientific setting of livestock loading and oil extraction area and the optimization of grassland resource utilization strategy in Daqing.

The saline and alkaline land in Xinjiang is vast， and clarifying the characteristics of carbon， nitrogen and phosphorus stoichiometric cycles between organs and soil in the native drought-resistant and saline-tolerant Elaeagnus angustifolia forests in Xinjiang is of great significance in promoting the construction of desert， saline and alkaline vegetation and ecological restoration in the middle and lower reaches of the Tarim River. The E. angustifolia forests（E.moorcroftii and E. angustifolia） in the lower reaches of Tarim River were taken as materials， and the stoichiometric characteristics of different organs（leaves， branches， roots） and soils of two tree species in the forest and their interrelationships were analyzed， respectively. The results showed that： （1）The average content of carbon， nitrogen， and phosphorus in the leaves of E. angustifolia forests were 424.36-484.40 g⋅kg^-1， 33.83-38.71 g⋅kg^-1 and 1.50-2.20 g⋅kg^-1， respectively， and with moderate C and N contents and slightly low P content. The N∶P ratios of E.moorcroftii（17.64） and E. angustifolia（22.82） were higher than 16， indicating the growth limited by P. （2）There were significant differences in ecological stoichiometric characteristics of each organ in the E. angustifolia forests， and the contents of N and P were the largest in leaves. （3）The soil elements content of the E. angustifolia forests were significantly affected by soil depth， showing a vertical decrease along the soil profile and presenting a certain enrichment in the surface layer （0-20 cm）. The C∶N， C∶P and N∶P of the 0-60 cm soil layer were 17.94， 9.32 and 0.62， respectively， and the mineralization capacity of soil N element was weak， and N was deficient. （4）Soil N and P contents of E. angustifolia forests were significantly positively correlated with root N and P contents（P<0.05）， leaf N contents were significantly negatively correlated with 0-20 cm soil C and N contents of each layer（P<0.05）， and significantly positively correlated with soil P contents； leaf P contents were significantly and positively correlated with soil P contents of each layer， and there was no significant correlation between leaf C with soil C（P>0.05）. In general， in poor and severe saline-alkaline soils， the E. angustifolia forests stored less nutrients in branches and roots and usually supplied preferentially nutrients to leaves， the upper part of the E. angustifolia forests was mainly limited by P， and the underground part was mainly limited by N. Therefore， the overall nutrient cycling in E. angustifolia forests was limited by N and P elements.

To investigate the phenotypic diversity of growth and nut traits of Juglans mandshurica natural forest germplasm resources， 77 germplasms of J. mandshurica from the main distribution areas of Heilongjiang Province were used as materials， and six descriptive phenotypic traits and 10 quantitative traits were analyzed， and principal component analysis and systematic clustering method were used for comprehensive evaluation. The results showed that the variation coefficients of descriptive phenotypic traits were in range of 4.61%- 43.49%， variation coefficient of nut color（43.49%） was the highest， Shannon-weaver diversity index of depth of surface grooves（0.829） was the highest， variation coefficient（4.61%） and diversity index（0.120） of top prominence were the minimum， the phenotypic traits were stable relatively. In terms of quantitative traits， variation coefficients of factors related to nut size and growth were 4.40%-12.05% and 22.60%-35.57%， respectively； variation coefficient of yield per plant（48.50%） was the highest， and the mean value of single nut mass was 9.36 g. There were significant positive correlations between single nut mass and the indicators nut vertical diameter， horizontal diameter， lateral diameter（P<0.01）， respectively. The yield per plant was significantly positively correlated with growth factor， nut size and single nut mass（P<0.01）， respectively. The principal component analysis of 10 quantitative traits showed that the cumulative contribution rate of four indicators extracted was 88.410%. The results of cluster analysis showed that 77 germplasms could be divided into four groups， group Ⅰ could be used to breed fruit and timber， group Ⅱ could be used to breed fruit cultivars with high yield and large fruit shape. MH9 in group Ⅱand BW12 in group Ⅰ could be used as parent materials for breeding fruit cultivars with high yield and large fruit shape； BW14 in group Ⅰ could be used as parent materials for breeding timber cultivars.

The volatile oil contains many kinds of active ingredients， which can be used as an indicator for the quality evaluation of Asari Radix et Rhizoma， and the difference of volatile oil components of different origins is of great significance for the quality research and development and application of Asari Radix et Rhizoma. Gas chromatography-mass spectrometry（GC-MS） was used to qualitatively and relatively quantify the volatile oil components of different origins， combined with data analysis software， and the differential compounds of different origins were identified by cluster analysis（HCA）， principal component analysis（PCA） and orthogonal partial least squares discriminant analysis（OPLS-DA）. The results showed that a total of 59 compounds were detected in 25 batches of Asari Radix et Rhizomasamples， which could be divided into three categories according to different origins. Further analysis showed that the difference in volatile components of Asari Radix et Rhizoma was significantly correlated with different origins， and 11 compounds such as α-terpineol， myristic ether and camphene were identified as different components of different origins. The differential components screened by chemometrics can be used to distinguish different origins and provide a comprehensive reference for the rational use of Asari Radix et Rhizoma resources.

To explore the effects of irrigation and fertilization on the growth and photosynthetic physiological characteristics of Populus cathayana × canadansis ‘Xinlin1’， and to select the optimal measures of irrigation and fertilization for promoting the growth of ‘Xinlin1’， 10-year-old ‘Xinlin1’ poplar was used as material， and four irrigation levels ［-20 kPa（I₂₀）， -33 kPa（I₃₃）， -45 kPa（I₄₅）， unirrigated（I₀）］ and seven fertilization levels ［urea 500 g?plant^-1（N₁）， urea 1 000 g?plant^-1（N₂）， urea 1 500 g?plant^-1（N₃）， compound fertilizer 500 g?plant^-1（F₁）， compound fertilizer 1 000 g?plant^-1（F₂）， compound fertilizer 1 500 g?plant^-1（F₃） and control（CK）］ were set to determine the height， diameter at breast height（DBH）， leaf physiological and photosynthetic indexes of ‘Xinlin1’ poplar， respectively. The results showed that： （1）Irrigation and fertilization significantly increased the annual increment of DBH， tree height and volume. The highest annual increment of DBH， tree height and volume under I₂₀ irrigation was 18.6%， 40.6% and 60.6%， respectively， compared with no irrigation. The annual increase in DBH， tree height and volume per plant under F₂ fertilization were the largest， reaching 2.47 cm， 2.09 m and 0.097 m³， with an increase of 8.3%， 7.8% and 15.3% compared with no fertilization， respectively. I₂₀F₂ showed the largest growth rate， which was significantly higher than other treatments. （2）Irrigation and fertilization significantly increased chlorophyll content， soluble sugar content， soluble protein content， glutamine synthetase activity， nitrate reductase activity， net photosynthetic rate and stomata conductance. I₂₀F₂ treatment had the largest activities of soluble protein， glutamine synthetase and nitrate reductase and net photosynthetic rate. （3）Correlation analysis showed that growth traits（DBH， tree height and annual volume increase） of ‘Xinlin1’ poplar were positively correlated with leaf physiological traits and net photosynthetic rate， and negatively correlated with intercellular CO₂ mole fraction. Irrigation and fertilization significantly changed the physiological characteristics of leaves， improved the photosynthetic capacity， and promoted the growth of ‘Xinlin1’ poplar. Under I₂₀F₂ treatment， the physiological indexes and net photosynthetic rate were the highest， and the tree growth reached the optimal level. Therefore， sufficient water supply（irrigation threshold was -20 kPa） and application of compound fertilizer 1 000 g?plant^-1 were the optimal measures to improve photosynthetic physiological characteristics and promote the growth of ‘Xinlin1’ poplar.

To explore the effect of growth retardants on the rooting of Prunus humili rhizomes cuttings， ‘Jinou 1’ rhizome cuttings were used as materials. Optimal concentrations of growth retardants S₃₃₀₇ （uniconazole）， PP₃₃₃ （paclobutrazol）， and DPC （dikegulac） were screened by measuring rooting rate， germination rate， morphological indices， nutrients， oxidative enzyme activities， endogenous hormones during the rooting process of rhizome cutting. The results showed that the retardants S₃₃₀₇（50 mg?L^-1）， PP₃₃₃（100 mg?L^-1）， and DPC（100 mg?L^-1） significantly increased the rooting rate of P. humilis rhizome from the control of 22.16% to 78.02%， 57.10%， and 56.70%， respectively. During the rooting process of rhizome cuttings， growth retardant treatments also increased the contents of soluble sugars， starch， soluble proteins， and the activity of POD， SOD and CAT. In addition， the retardant treatment promoted the content of IAA and expression levels of IAA synthesis genes ChTAA1， ChTAA2 and ChYUC1 in rhizome cuttings and inhibited the synthesis of GA₃， ABA， and ZT， which was favorable for the rooting of P. humilis rhizome cuttings. This experiment provided a theoretical basis for the propagation of P. humilis rhizome cuttings.

In recent years， frequent extreme weather and uneven distribution of rain have caused water shortage in the key growth period of Codonopsis pilosula， leading to declines in quality and yield. To solve this problem， this study used Codonopsis pilosula as the object， investigated the regulatory effects of C. pilosula polysaccharides（CPPs） synthesis under drought stress by siliconaddition based on glycolysis （EMP） and tricarboxylic acid cycle（TCA）. Three groups were set up： water（CK）， drought by 15% PEG-6000（D） and drought by 15% PEG-6000 after silicon treatment（Si+D）. In Si+D group， 200 mL of 2 mmol?L^-1 potassium silicate solution was applied to each basin on the 7th day before drought treatment. EMP and TCA-related substances， enzymes activity and key genes expression were measured at 7， 14 and 21 days respectively after drought treatment. Meanwhile， the contents of CPPs and its biosynthesis-related substances were measured to analyze comprehensively the regulation of CPPs synthesis by silicon under drought stress. The results showed that： （1） Drought stress weakened the content of photosynthetic pigment of C. pilosula， accelerated the consumption of sucrose， fructose and glucose， and enhanced the energy consumption in EMP and TCA pathways for the synthesis and accumulation of starch and polysaccharide， and there was a mutual fluctuation of yield and quality. （2） The silicon addition enhanced the content of relative leaf water of C. pilosula， inhibited the content of photosynthetic pigments， increased the sucrose and fructose contents， decreased the enzymes activity related to starch synthesis and increased the enzymes activity related to starch decomposition， resulting in the decrease of starch and polysaccharide contents， but the overall yield of C. pilosula were increased. Silicon addition promoted the EMP pathway of C. pilosula under drought stress， prevented the TCA cycle process， and made pyruvic acid， the end product of EMP， synthesize into citric acid and its accumulation. The application of silicon might affect the photosynthesis of C. pilosula， regulate the energy generation and distribution of EMP and TCA pathways， enhance the ability of C. pilosula to resist drought， and play a positive role in the synthesis of polysaccharide and the quality and yield of C. pilosula. However， with the extension of drought stress time， the regulation effect was weakened gradually.

Polysaccharide from the stems and leaves of Dendrobium officinale was extracted and purified by water extraction and alcohol precipitation， and its hygroscopic， moisturizing， whitening and antioxidant activities were clarified， respectively. The yield of polysaccharide（L-POL） extracted and purified from D. officinale leaves was（13.95±0.27）% and the purity was（92.14±7.75）%. L-POL had good moisture absorption and moisture retention effects， and moisture absorption rate and moisture retention rate were（9.50±0.57）% and （25.13±0.24）%， respectively. L-POL had strong DPPH free radical scavenging ability and in vitro tyrosinase activity with IC₅₀ value of 2.232 and 54.930 g⋅L^-1， respectively. L-POL with a concentration of 125 mg⋅L^-1 could significantly inhibit the synthesis of melanin by mouse melanoma cells B16 with an inhibitory rate of 36.89%. In addition， L-POL with concentrations ranging from 75-300 mg⋅L^-1 was not cytotoxic to mouse melanoma cells（cell viability of 89.33%-102.00%）. The high-purity L-POL had good antioxidant， whitening， moisture absorption and other activities， which provided a new idea for the further development and utilization of D. officinale resources in cosmetics or whitening functional foods.

The morphology of Artemisia argyi flowers at various developmental stages was observed， and the contents of volatile components were determined using GC-MS. The pollen structure was examined using optical and scanning electron microscopes， and the pollen development process was observed under a transmission electron microscope， respectively. The results showed that A. argyi had oval head inflorescence with purple or yellow corolla at blooming， the relative content of most medicinal volatile components such as eucalyptol， camphor and borneol decreased with blooming， while the content of thujone gradually increased. The pollen of A. argyi had the structure of three germination pores and three channels， and the surface was adorned with a thorny， granular compound ornament， and the thorns were blunt and interspersed with granular protrusions， spherical and oblong in shape， exhibiting pollen dimorphism. By observing the characteristics of pollen mother cell stage， mononuclear microspore stage， binucleate pollen stage， pollen maturation stage and the environmental change process in the pollen sac， it was found that there were a large number of abnormal pollen grainsin the A. argyi anthers. The characteristics of A. argyi flowers and pollens were systematically investigated， which would provide a reference for morphological， palynological， and reproductive research on A. argyi.

Flavonoids play important roles in plant somatic embryogenesis. In order to explore the effect of flavonoids on somatic embryogenesis of Korean pine（Pinus koraiensis）， the embryogenic calluses were used as materials. The proliferation rate of embryogenic callus and the number of somatic embryos， and oxidative stress indexes in embryogenic callus were assessed after adding flavonoids（quercetin， naringenin， catechin） in different concentrations and phenylalanine aminolytic lyase inhibitor（2-aminoindan-2-phosphonate hydrochloride）. The results showed that the proliferation rate of embryogenic callus was significantly decreased with increasing levels of flavonoids， while the number of somatic embryos induced increased first then decreased， and the number of somatic embryos reached the peak under the treatment of exogenous flavonoids at 20 μmol?L^-1. After treatment with flavonoids， the total reactive oxygen species（ROS） level， hydrogen peroxide（H₂O₂） content and malondialdehyde（MDA） content were reduced in embryogenic callus； the superoxide dismutase（SOD） activity was increased； the catalase（CAT）， peroxidase（POD）， ascorbate peroxidase（APX） and glutathione peroxidase（GPX） activities were decreased. In summary， exogenous flavonoids might regulate cell proliferation and callus differentiation by affecting the level of oxidative stress indexes in embryogenic callus， hence， promote the formation of somatic embryos of Korean pine.

In order to establish a simple， safe and rapid paraffin sectioning method to reduce the use of poisonous agent xylene in experimental process，the leaf and fruit of four periods of Ziziphus jujuba ‘Lingwu Changzao’were used as materials， and the anatomic features were observed by an improved low melting point polyester wax（Steedman’s wax） sectioning technique， and a set of feasible methods for paraffin sectioning preparation of plant tissues were established by improving embedding reagent， omitting the xylene transparence step， shortening the experimental processes， and compared it with conventional paraffin sectioning technique， it provided a new method for studying the plant tissues structures characteristics. The results indicated that the morphological structures of the leaf and fruit were complete and the staining was clear in paraffin sectioning obtained by the improved low melting point polyester wax（Steedman’s wax） sectioning method， the experimental procedures were not only simplified and the whole experimental time had been shortened， but also the quality of slices obtained using the improved sectioning technique was same as the conventional paraffin sectioning， and the experimental procedures were optimized and the use of toxic reagents such as xylene was avoided and experimental time was saved， and the efficiency of plant paraffin making was improved， it would be worthy of being used in more plant morphological anatomy research.

According to Article 9.2 of International Code of Nomenclature for algae， fungi， and plants （Shenzhen Code， 2018）， the collecting number errors in the protologues of seven taxon names （Asteraceae） in China were corrected， including Ajania latifolia C.Shih， Cirsium tsoongianum Y.Ling， Doronicum gansuense Y.L.Chen， Erigeron taipeiensis Y.Ling & Y.L.Chen， Heteropappus eligulatus Y.Ling ex Y.L.Chen & al.， Leontopodium micranthum Y.Ling and Saussurea lanata Y.L.Chen & S.Y.Liang. The holotypes of these species were deposited at China National Herbarium （PE）， Institute of Botany， Chinese Academy of Sciences.