Based on 13 typical tropical coniferous-broadleaved forest ecotones, we analyzed the environmental characteristics along/of ecotones using belt transect method. The results showed that, as the stand changed from coniferous forest zone to broadleaved forest zone across coniferous-broadleaved forest ecotone, soil pH, soil organic content, total N, available N, available P, and available K contents showed an order of broadleaved forest zone > coniferous-broadleaved forest ecotone >coniferous forest zone. The total K, litter depth and light factors showed an order of coniferous forest zone > coniferous-broadleaved forest ecotone >broadleaved forest zone, total P. The soil water content and soil gravel content had no significant differences over the different ecotones. In consideration of all these environmental factors studied, Pearson's correlation analysis showed that the all environmental factors had obvious correlations with each other except for soil water content and total P that had no obvious correlations with other environmental factors. Principal component analysis showed that soil pH, soil organic content, litter depth, and light factors took more effect to the first axis, whereas total N and available P took more effect to the second axis. They were all the main determinants for the distribution of the three different stand zones.

We investigated monthly soil respiration (R_s) and the affecting factors under 19-year-old Mytilaria laosensis and Cunninghamia lanceolata plantations replanted in a C. lanceolata woodland slash in subtropical China. The results showed that the average annual R_s rates were 2.95 μmol CO₂·m^-2 s^-1 under M. laosensis plantations and 2.37 μmol CO₂·m^-2 s^-1 under C. lanceolata plantations. The Q₁₀ value was 1.83 under M. laosensis plantations, which was significantly lower than 1.99 under C. lanceolata plantations. The R_s rates exhibited distinct seasonal patterns under both M. laosensis plantations and C. lanceolata plantations and were dominantly controlled by the soil temperature, accounting for 77.0% and 81.6% of monthly variation, respectively. Linear regression analysis showed that R_s was significantly correlated with annual litter biomass, fine root biomass, soil organic carbon content, light fraction organic carbon content, microbial biomass carbon concentration and dissolved organic carbon concentration (P<0.05). Stepwise regression analysis showed that litter biomass and microbial biomass carbon concentration were the most important affecting factors of R_s. Our results suggest that differences of R_s in different vegetation types may be attributed to the variations in the quantity and quality of litter input and the soil microbial biomass.

Forestry department has been going to collect data reasonably and termly. But, the development of forest resource data model and data updating mode are slower than the development of the data acquisition. Each set of data exists in isolation and has little relation with each other so that it could not represent the spatio-temporal change of forest resources systematically and thoroughly. Based on combining the spatio-temporal theory with forest resource information management, this article put forward a framework, which consists of spatio-temporal model, data collection, data updating and spatio-temporal database. In the framework, the data collected by different method would be formed as 3 hierarchies of objects, which then would be updated into the spatio-temporal database defined by spatio-temporal data model. The data in the database should keep the validity of object relation, spatial constraint and time constraint. The article verified the feasibility of the framework by a prototype system.

Based on 104 sample tree trunk and branches parse biomass data in 19 sample plots, established the compatible model of aboveground total model and component of Larix gmelinii natural forest, by using weight function and simultaneous linear equations to eliminate heteroscedasticity and measurement error equation. The results showed that: 1) Compatibility biomass model solved the total biomass model and component biomass model of incompatible problem, and the compatibility of biomass model prediction accuracy was higher than empirical model; 2) Utilize modern built biomass model parameter determination coefficient R² and compatibility model deviation statistics estimate the standard deviation SEE, mean estimated error MPE, mean relative deviation ME, mean relative deviation absolute MAE were 0.907-0.947,1.887-17.368,1.011%-2.703%,-4.937%-6.998%,5.408%-10.886%; 3) Statistical analysis of the measured values of Larix gmelinii natural forest in the northern Greater Khingan Mountains, got the region single natural forest stem biomass covered the aboveground biomass of 60.37%-76.80%, stem biomass proportion with the increase of forest age increased first, then decreased. Bark biomass covered the aboveground biomass of 7.15%-20.11%, the proportion trend of decrease with the increase of forest age. Branch biomass covered the aboveground biomass of 8.51%-14.29%, branch biomass proportion along with the age increasing basic rendering. Leaf biomass covered the aboveground biomass of 5.12%-7.09%,leaf biomass accounted for the proportion of the biggest was low forest age.

The tannin extract contents in different organs of Quercus variabilis are mainly influenced by ecological factors. In order to understand the principal ecological factors affecting Q. variabilis tannin extract, and to provide scientific cultivation measures of Q. variabilis and an reference for efficient utilization of the tannin extract resources of Q. variabilis, a total of 108 Q. variabilis trees and the major ecological factors were investigated and determined in 6 sample plots of three different distribution regions (south slope of Qinling Mountains, north slope of Qinling Mountains, Loess Plateau) in September 2012. The tannin content of different organs of Q. variabilis in the 3 different distribution regions (6 sample sites) was analyzed by UV spectrophotometry and the grey correlation degrees with the ecological factors were calculated. The results showed that there was a significant difference in tannin content among the different regions. The tannin content in the 3 different distribution regions from high to low was the south slope of Qinling Mountains, the north slope of Qinling Mountains and the Loess Plateau. The tannin content of Q. variabilis valonea in the 6 regions was highest, followed by the bark, leaf, branch, and the tannin content of root and stem was lowest. The principal soil factors that influenced tannin content of different organs of Q. variabilis were available nitrogen, available phosphorus, and available potassium. Soil organic matter was one the main factors affecting the effective component content of tannin extract of Q. variabilis. There was a positive correlation between tannin content of organs and these main soil factors. The principal climatic factors that affected tannin content of different organs were frost-free periods, annual sunshine hours and annual mean rainfall. The frost-free periods and annual mean rainfall were positively correlated with tannin content in different organs of Q. variabilis, while the annual sunshine hours was negatively correlated with tannin content in different organs of Q. variabilis. The region with longer frost-free periods, more rainfall, shorter sunshine hours, more organic matter and lower soil nutrients content could prior be chosen as cultivation area of Q. variabilis for high tannin production.

In this study, the scenic beauty estimation (SBE) method was applied to assess the within-forest landscape of the plantation and secondary forests by analyzing the present status of urban forests in Shenzhen. The major factors influencing the forest landscapes were analyzed and used to build the forest landscape model. The relationship between main landscape elements and forest landscape quality was also discussed. The main results showed as follows: The plantation had higher scenic quality of the within-forest landscapes in Shenzhen than the natural secondary forest, with SBE values of 0.092 and -0.187, respectively. The SBE value of Acacia mangium communities was the highest. The SBE value of Adina pilulifera+Psychotria yunnanensis+Acacia confusa communities was the lowest. The model for the within-forest landscape in the plantation was SBE=0.131 + 0.177x₅-0.195x₈+ 0.208x₉-0.162x₁₀-0.129x₁₂-0.000 08x₁₇+ 0.113x₂₁+ 0.007x₂₃-0.571x₂₅. By this model, the major landscape factors affected the scenic quality of the inside forest landscapes were different between the plantation and the natural secondary forest. Within the plantation, the determinant elements mainly included understory height, abundance of interstratum plants, arrangement of trunks, the amount of fallen woods, uniformity of ground plants, stand age, branch height, coverage of ground plants and stand density. The model for the inside forest landscape in the natural secondary forests was SBE=-2.016 + 0.157x₁+ 0.215x₄+ 1.753x₁₆-0.063x₁₈+ 0.021x₂₄. By this model, the main landscape factors affected the scenic quality of the inside forest landscapes were litter, crown density, viewable distance, bark's color and abundance of arbor.

The morphological structure and development of tannin cells in bark of Hevea brasiliensis were studied by using transmission electron microscopy and light microscopy. The results showed that tannin-like materials distributed in all kinds of parenchyma cells in secondary phloem except for companion cells. The tannin-like materials were present in large amounts in the parenchyma cells around the laticifers, the stone cells, cork layer cells and phelloderm cells. Under the electron microscope,four forms of tannin-like materials,i.e., flocculent, irregular, granular and plate-like, could be distinguished in the large central vacuoles of tannin cells. During the course of development of tannin cell, tannin-like materials firstly deposited into small vesicles in cytoplasm,then stored mainly in the large central vacuole along with the synthesis of tannins. As a result, the tannin-like materials filled the large central vacuole of the mature tannin cells. The accumulation of tannin-like materials was largely enhanced by mechanic wounding, over-exploitation,and application of either Ethrel or Jasmonate (JA), reflecting the response of rubber tree to various stress factors.

This study tested 258 families of Loblolly pine (Pinus taeda) with different genetically improved levels introduced from the USA. A mixed linear model in terms of restricted maximum likelihood estimate (REML) and best linear unbiased prediction (BLUP) was used to predict breeding values of height and diameter at breast height (DBH) for the tested families and single trees at the age of 14 years. The phylogenetic relationship matrix was used to promote the accurate of the prediction. The control-pollinated families had 1.40 cm of average gain for DBH, being the highest gain in the whole trail. Thirty nine excellent families, accounting for 15% of all the tested families, were selected based on the predicted breeding values. These families could be re-introduced from the USA and used for afforestation. By using combined selection 77 individuals, accounting for 1% of all the tested trees, were selected to enrich the second generation breeding population. Ten individuals among them were selected into the second generation nucleus breeding population, remaining 67 into the second generation main breeding population. The accurate prediction based on BLUP and the selection based on individual tree breeding values in the advanced-generation breeding program would improve the accuracy and the genetic gain of selection. The breeding program and the trail design should be improved to achieve the maximum effect when using the advanced statistics method such as ASReml. The balanced incomplete block design (BIB) could be used to conduct the field experiment design when the families involved in the trail were too many, which would help to evaluate the factors in the trail and award the maximum achievement.

In an effort to better understand the factors that regulate α-linolenic acid metabolism in Camellia oleifera seeds, the transcriptome library and expression profile of C. oleifera seeds both in the fruit expanding period and at the peak stage of lipid biosynthesis have been constructed and the functional genes related to α-linolenic acid metabolism have been analyzed in detail. Study on transcriptome showed that there were one hundred and twelve non-redundant gene unigenes related to α-linolenic acid metabolism and ninety-four unigenes related to biosynthesis of unsaturated fatty acids of C. oleifera seeds, including twelve kinds of key enzyme genes regulating α-linolenic acid metabolism. The results of expression profile analysis showed that these genes had different expression patterns. These genes regulate the synthesis of α-linolenic acid and its conversion process to other unsaturated fatty acid at different developmental stage. The real-time quantitative RT-PCR analysis revealed relative expression regularity of the key enzyme genes such as LOX, AOS, ACOX, AOC, OPR, AACT, PLA2, HPL, DOX, MFP, FAD2, FAD3 in α-linolenic acid metabolism in fruit expanding period and the oil synthesis peak stage, which agreed with the results of expression profile analysis. The findings would provide a scientific basic for Camellia breeding of good quality with increasing content of α-linolenic acid.

Mating system is the basic property of plant populations and biological foundation for germplasm preservation as well as genetic improvement. In this study we applied developed 8 microsatellite loci with high polymorphism to analyze 50 half-sib progenies from each of 3 independent flowering culms of Phyllostachys edulis. The results showed that flowering culms in three different locations were fertilized with foreign pollen, which generated progenies with different microsatellite genotypes and genetic diversity. The overall estimates of outcrossing rate t_m of single-locus and t_s of multi-locus for the three culms were 0.089, indicating that the reproductive system of P. edulis predominantly involved in self-fertilization with a certain proportion of outcrossing to produce genetic diverse progenies. This is the first report so far on estimation of outcrossing rate for monopodial bamboo species such as P. edulis by DNA molecular markers.

Human activities are greatly changing the way and rate of nitrogen input to the land ecological system on a global scale,which has a significant impact on the structure and function of soil ecosystem. To clarify the carbon source utilization of soil microbial communities in response to nitrogen addition, a field experiment was conducted in a Cinnamomum camphora plantation in Hunan Forest Botanical Garden. Three levels of nitrogen addition were applied, such as control (0 g·m^-2), low nitrogen (5 g·m^-2) and high nitrogen (15 g·m^-2). Using the BIOLOG AN,FF,Gen Ⅲ and YT microplate methods, carbon source utilization of soil microbial communities (anaerobic bacteria, fungi, gram bacteria and yeast) was investigated after 1 year treatment under different nitrogen additions. The results showed:1)Metabolic activity of soil microbial communities with nitrogen additions reduced to different degrees,and the higher the nitrogen concentration,the weaker soil microbial metabolic activities.2)Diversity index analysis showed that nitrogen inputs affected the diversity of four microbial communites. The richness of the four soil microbial communities increased, but the evenness reduced, and the dominance of the anaerobic bacteria, fungi and gram bacteria reduced under nitrogen additions.3)The analysis of carbon source utilization showed that the utilization of other carbon sources had increased although the carbonhydrates were still the main carbon resources of microbe utilization after nitrogen inputs. Principal component analysis showed that different nitrogen additions had a great impact on the soil microbial communities. The carbon sources utilization of soil fungi and anaerobic bacteria was greatly influenced by nitrogen input, but the effects of gram bacteria and yeast were relatively weakly by the influence of nitrogen input.

In order to better assess the wind protection effect of oasis protection forest in winter and spring in northern China, we evaluated the effect of farmland shelterbelts in northern China on the forest ground wind in winter and spring. The relative wind speed of shelterbelts stickers' layer was used as the objective function. Based on the dynamic equilibrium, the approximate correspondence relationship between the stock volume index (per unit area of farmland owned by the stumpage) and wind protection effect of the farmland shelterbelts in winter was used to evaluate the effect of farmland shelterbelts in northern China on the forest ground wind in winter and spring. The results showed that the overall stock volume was insufficient in northern China oasis protection forest, and the wind protection effect was poor in winter and spring. Occasionally, a very good windbreak effect was observed in some locals, but the situation was not universal. Moreover, we found that the incremental benefit of wind protection was inversely proportional to the stock volume index. Bare arable land and the areas with smaller stock volume had bigger incremental space. Pruning operated in smaller stock volume index areas had more significant influence on wind protection effect. Thus, it is not necessary to keep collaterals by sacrificing the economic value of wood in those areas with bigger stock volume index. For those areas with relatively big stock volume index, the growing volume is not necessary bigger than the harvest volume and the storage volume.

To explore the biological control measure of Agrilus mali Matsumura, four species of bethylid wasp in the genus Sclerodermus (S. pupariae, S. guani and another two species) were used to test their control capacity to pest by bagging with 5 release ratio (parasitoid:host: 0.5:1, 1:1, 2:1, 4:1, 8:1). Results showed that, all four wasps were able to successfully parasitize on A. mali, especialy for S. pupariae, which caused 65.56% reducing rate with release ratio 8:1 in 30 d. Then S. pupariae was tested by directly releasing on the damaged apple trees with the 5 release ratios. After 30, 45 and 60 d, the control effects were checked respectively. The result showed that, the treatment with 8:1 release ratio, after 60 d performed the best, with 50.97% corrected mortality. This research provided a successful case by using bethylid wasps to control A. mali, and offered a reference for appropriate release ratio of S. pupariae in the field.

The G protein coupled receptors (GPCRs), known as transmembrane receptors, play an important role in drug research and development by activating G protein involved in inside signal transduction pathways. In present study, the full length cDNA of GPCR (namely LdOA1) was isolated from Lymantria dispar transcriptome. The open reading frame (ORF) of LdOA1 was 453 bp encoding a protein of 150 amino acid residues with the molecular mass of 17.54 kDa and theoretical pI of 9.76. Phylogenetic analysis of GPCR proteins showed LdOA1 of L. dispar clustered into a group with Danaus plexippus. We further investigated the expression of LdOA1 in 3^rd instar L. dispar larvae under deltamethrin, carbaryl and omethoate stresses using real-time PCR. The results showed that LdOA1 in L. dispar was obviously inhibited by deltamethrin, carbaryl and omethoate.

The diversity, variation, predicted protein function domains and evolution of thymidylate kinase gene (tmk),which was obtained by cloning DNA sequencing of PCR products with designed primer from paulownia witches'-broom phytoplasmas Pingshan strain (PaWBPs) in Hebei Province and Ji'an strain (PaWBJan) in Jiangxi Province were comparatively analyzed by DNAMAN and MEGA software. The 52 and 24 different tmk-a homologues respectively from the cloned 93 sequences of PaWBPs and 41 of PaWBJan in total were identified, whereas the tmk-b gene sequence was relatively conserved, with 99.8% similarity and only one amino acid variation of the predicted proteins between the two strains. All tmk-a ORFs were classified into tmk-a-1 (639 bp) and tmk-a-2 (627 bp). The ratio of tmk-a-1/tmk-a-2 in PaWBPs and PaWBJan was 2.5 and 3.3, respectively. Five cloned tmk-a-1 sequences of PaWBPs were the same as one in PaWBJan as well as tmk-Y of jujube witches' broom phytoplasma. In addition, PaWBPs and PaWBJan respectivety contained up to 48.1% and 41.7% of predicted tmk-a pesudogenes in total tmk-a due to the multiple locus mutation. Rich sequence variability was found in tmk-a homologues of PaWBPs and PaWBJan and there existed three functional domains in amino acid sequences of both tmk-a and b which are necessary for thymidylate kinase activity. The phylogenetic analysis showed that all the tmk-a homologues of both strains with tmk-X and Y were clustered into clade I, while tmk-b with wheat blue dwarf tmk-2 into clade Ⅲ, suggesting that tmk-b nucleotide sequences consistent with highly conserved 16S rDNA could be used for the classification of phytoplasmas on 16Sr group levels whereas diverse tmk-a might be helpful for analyzing the genetic variation and diversity of different phytoplasma strains.

Effects of the protein toxin from Arthrinium phaeospermum on the membrane fluidity, surface electronic potential, swelling, aggregation and the contents of lipid peroxide MDA, Coenzyme Q 10 (CoQ10), and respiration function of the mitochondria from shoots of different Bambusa pervariabilis×Dendrocalamopsis grandisvarieties were determined by the different detection techniques (fluorescence polarization, neutral red dye, oxygen electrode, etc.). The results showed that the protein toxin caused the membrane fluidity weakening, surface electronic potential and aggregation decrease, swelling increase of mitochondria in four bamboo varieties. With the protein toxin treatment, the CoQ10 content decreased, the MDA content increase, the activities of cytochrome c oxidase (CCO) and ATP decrease, respiratory control ratio (RCR) and oxidative phosphorylation ratio (P/O) significantly reduced. The above results demonstrated that the protein toxin damaged the mitochondrial membrane, increased the lipid peroxidation of mitochondrion, destroyed the membrane integrality, and inhibited the respiration. In term of all of the above indices, the effect of protein toxin on the resistant varieties (3# and 6#) was significantly weaker than that on the susceptible varieties (8# and 30#).

The ultrasonic propagation parameters in amur linden(Tilia amurensis)log specimen which was in intact and defective status respectively were measured and obtained. These parameters were then used as training set and test set to classify the hole size in log based on support vector machine(SVM). Furthermore, a kind of method to quantitatively determine the location of defect point on the cross section of log was proposed and improved. Based on this, the two dimensional simulation image of internal hole defect in log was constructed. The results showed that: 1) It was feasible to classify the hole size in log using SVM and the identification accuracy was 84.78%.2) The two dimensional simulation image of hole defect in the cross section was in good agreement with the actual image of log specimen.

The study analyzed the economic growth, the industry evolution and its structure differences of the forestry using a dynamic shift share analysis, based on 17-year forestry outputs (from 1995 to 2011) of 13 provinces (autonomous regions) of the southern collective forestry region of China (SCFRC). Results indicated that the forestry economy in the SCFRC had a rapid growth rate and maintained better quality on forestry industry structure, bringing regional competitive advantages compared with the overall national level. The second and third industries of the forestry with regional competitive advantages had a higher growth rate and a higher quality on industrial structure than the whole nation while the primary industry does not. Compared with the SCFRC, forestry economic industry had maintained a high growth rate in Jiangsu, Guangdong, Anhui and Guangxi and the competitive advantages of the industry structure had been found in Jiangsu, Zhejiang and Fujian. The forestry industry had competitive advantages in Jiangsu, Anhui, Guangdong and Guangxi. The study further adopted a cluster analysis to divide the 13 provinces into four categories by forestry industry developing: the advantages type, industrial developing type, the advantage to be improved type, the advantage-lag type. The associated policy implications and suggestions were provided according to the characteristics of different developing paths.

Agroforestry system is a dynamic natural resource management system. This paper summarized the research progress of agroforestry system in the utilization of solar radiation, water, nutrition, land and other natural resources. We concluded that agroforestry system was important to improve the utilization of natural resources. However, the degree of this improvement was different due to differences in climate, forest category and tree density and stand age, crop types. The research scale, research content, method and research prospects were also proposed in this paper.

Tracheary elements (TEs) are main component in the xylem that are highly specialized for transporting water and solutes up the plant during plant growth and development, and have complex morphological characteristics. The mature plant cells can be converted into TEs by processes of differentiation or transdifferentiation in an appropriate vitro system. Recently constructed of vitro culture systems for Zinnia, Arabidopsis, Populus and other species have been facilitating our observation of the morphological changes during TEs differentiation and understanding the factors that influence the differentiation process. Previous researches indicated that TEs differentiation processes vary with plant cells, and many factors such as phytohormone, xylogen, Ca²⁺, osmotic pressure, initial cell population density, pH and so on, play great roles in regulating TEs differentiation. At present, the Zinnia vitro culture system is the relatively mature system for observing TEs differentiation while Populus system is the most promising system for woody plant. These model systems provide an excellent platform for study of TEs differentiation at single cell level, and greatly advance our understanding of TEs differentiation process and its control mechanism at the molecular level for ultimate goals of wood improvement.

Based on the statistical analysis of data collected from 658 farmers through a questionnaire survey from 6 provinces in three regions of eastern, middle and western China, the multilayer fuzzy comprehensive evaluation was used to empirically analyze the satisfaction evaluating system of forestry' specialized cooperative organization. In the analysis, the evaluation index weight of satisfaction evaluation was obtained based on estimated parameters of the structural equation model. The results showed that the farmers' satisfaction with forestry' specialized cooperative organization was in a medium level. Among all satisfaction indexes in the analysis, farmers were most satisfied with democracy satisfaction and least with service satisfaction. The democracy satisfaction and relationship satisfaction were higher than the average. The major factors which influenced farmers' satisfaction with forestry' specialized cooperative organization were service area, quality of service, income distribution inside the organization, communication of the management and the farmers.

In this study, five typical vegetation types were selected along the elevational gradient in Shennongjia Nature Reserve, including shrubs, coniferous forest, mixed forest between coniferous and deciduous broad-leaved forest, deciduous broad-leaved forest, and evergreen broad-leaved forest. The content of soil organic carbon (SOC), water dissolved organic carbon (WDOC), labile organic carbon (LOC),and microbial biomass carbon (MBC) and their allocation proportions to SOC were analyzed. Furthermore, the Pearson relationship was analyzed between soil active organic carbon and plant diversity or soil physiochemical properties. The results showed that the soil organic carbon in the surface layer increased with the elevation increased, except for the deciduous broad-leaved forest. Distribution characteristics of MBC and LOC content along elevation gradient were obvious,but WDOC content was independent of the elevation gradient. The contents of the three kinds of active organic carbon in different elevational gradients were in the order of: LOC >MBC >WDOC. The allocation ratios of MBC, LOC and WDOC to SOC did not significantly alter with elevational gradient. Pearson relationship showed that SOC and MBC had a significant negative correlation with the diversity of trees and shrubs (P<0.05), while LOC and WDOC content had no significant correlation with plant diversity. In addition, SOC and MBC were significantly positively correlated with the content of soil moisture, total nitrogen, available nitrogen, total phosphorus and total sulfur (P<0.01). LOC had a significant and positive correlation with the content of soil moisture, total nitrogen, available nitrogen and total sulfur (P<0.01). There was a significant correlation between LOC and total phosphorus (P<0.05). The results revealed that these factors had a dominating impact on SOC, LOC and MBC. WDOC content had no obvious correlation with soil factors.

Pinus koraiensis seedlings were used as experimental material to study the effects of rare earth elements La and Eu on the growth, polyphenols contents and PAL, C4H activities of P. koraiensis seedlings. The results showed that rare earth elements La and Eu could significantly promote the growth and increase the polyphenols contents of P. koraiensis seedlings. The optimum concentrations of La³⁺ and Eu³⁺ were 400 μmol·L^-1 and 100 μmol·L^-1, respectively. With the concentrations, the polyphenols contents and were 1.55 and 1.39 times higher, and the proanthocyanidins contents were 1.58 and 1.40 times higher than the control group, respectively. The PAL and C4H activities significantly increased and peaked in two days after the induction with 100 μmol·L^-1 La³⁺ and 400 μmol·L^-1 Eu³⁺. There were significant correlations between the enzymes activities and the synthesis of polyphenols. The 100 μmol·L^-1 La³⁺ showed more significantly promoting effects than the 400 μmol·L^-1 Eu³⁺ on both P. koraiensis seedlings growth and polyphenols synthesis. Rare earth elements La³⁺ and Eu³⁺ may have acted as inductor of P. koraiensis secondary metabolism, elicitor-induce defensive responses in P. koraiensis, activate the phenylpropanoid pathway, change the activity of related enzymes, and thus enhance polyphenols synthesis.

In this study, a field experiment was conducted to compare photosynthetic physiological characteristics and the chlorophyll fluorescence parameters in leaves among five Carya illinoensis varieties, including Farley, Colby, Shoshoni, Cheyenne and Mandan. The results showed that there were significant (P<0.05) or highly significant (P<0.01) differences in minimal fluorescence (F_o), maximum fluorescence (F_m), PSⅡ potential activity (F_v/F_o) and non-photochemical quenching (N_PQ) among the five varieties. The F_o and F_m of Shoshoni were higher than that of the other cultivars. The PSⅡ primary energy conversion efficiency (F_v/F_m) and PSⅡ potential activity (F_v/F_o) of Mandan were higher than those of the others, while the value of N_PQ was lower. The light compensation point (L_CP) of Mandan was significantly lower than that of the other varieties, indicating that it had a strong ability of using low light. Mandan and Shoshoni had higher maximum net photosynthetic rate (A_max) and relative chlorophyll content (S_PAD). Results of the correlation analysis showed that there were significant positive correlations between F_v and F_v/F_m, A_max and S_PAD. A significantly negative correlation was found between N_PQ and F_v/F_o.