Objective: The article is intended to identify the theoretical basis for and feasible approach to realizing the value of forest ecological products, therefore providing a plan for improving the mechanism of realizing the value of ecological products, achieving the strategic goal of "carbon peaking and carbon neutrality", promoting the Rural Revitalization Strategy, and accelerating the realization of common prosperity. Method: An in depth analysis of the concept, classification and basic attributes of forest ecological products was conducted to demonstrate the implications to realizing the value of forest ecological products in view of supply and demand. Nanping of Fujian, Ezhou of Hubei and Chongyi of Jiangxi were taken as case studies to analyze the specific measures of realizing the value of forest ecological products and their main effects. The theory of ecological economics was used to interpret the value realization mechanism of forest ecological products in three different ways: government as the main body, market as the main body and the combination of the two, respectively with a proposed approach to the value realization. Result: The implications to the value realization of forest ecological products : from the perspective of supply can be understood as what ways and means can be adopted to pay back the cost invested by producers, i.e. effectively encourage producers to be willing and able to provide more forest ecological products to the market, therefore optimizing the allocation of forest resources; From the perspective of demand can be understood asthrough the input of ecological, material and human capital elements, the welfare of consumers can be improved, increasing the recognition by consumers. Consumers are willing and able to pay a certain price to realize the transformation from ecological value to economic value of ecological products. Conclusion: By analyzing the practice of realizing the value of forest ecological products in China, aiming at forest ecological material products, regulation products and service products, the feasible ways to realize the value of forest ecological products in China are divided into three main types: the market is treated as the main body and a trading mechanism of forest material products is developed; the government is taken as the main body to construct the management mechanism of forest regulation products; the government and the market are combined to build a service mechanism for forest cultural products.

Objective: Zhejiang is the birthplace and the first practice place of the "Two Mountains "Idea. Establishing and improving the value realization mechanism of forest ecological products is an important exploration of Zhejiang to take the lead in practicing the "Two Mountains "Idea. This study evaluates the value realization efficiency of forest ecological products scientifically, in order to provide a scientific basis for measuring the practical effect and approach optimization of the practices of "Two Mountains" Idea in Zhejiang. Methods: An input-output indicators system for the value realization efficiency of forest ecological products was constructed, and the Super-SBM model and Malmquist index were used to measure the value realization efficiency of forest ecological products in Zhejiang Province and its temporal and spatial patterns using the InVEST model and the GIS technology, and to identify the approach optimization strategy. Results: From 2000 to 2020, the value of forest ecological products in Zhejiang Province showed a fluctuating upward trend. Carbon fixation and oxygen release, soil conservation, and cultural services were the main forest ecological products. The forest ecosystem played an important role in carbon fixation, oxygen release and soil conservation. In 2020, the value of forest ecological service products in Zhejiang Province was 1.94 times of the total output value of forestry, much higher than the national average of 1.73 times of the level of 12.14%. The total output value of forestry in Zhejiang Province shows a continuous growth trend. The secondary industry has become the absolute dominant industry of forestry in Zhejiang Province. The output value of the tertiary forestry industry has grown rapidly, and its proportion of the industry has continued to increase. The value realization efficiency of forest ecological products in Zhejiang Province is generally high, and the efficiency in 11 prefectures and cities continues to improve. Zhejiang Province has made remarkable achievements in practical application of the "Two Mountains" Idea; The total factor productivity of products shows a fluctuating and growing trend, and the fluctuating trends of total factor productivity in various regions and cities overlap with the changes in the technological progress index to a high degree. The improvement of forestry technical efficiency is the main reason for changing the value realization efficiency of forest ecological products. The total factor productivity is lower than 1, and its forestry technology progress has not played a positive role in promoting the value realization of forest ecological products, and the specific reasons for the realization efficiency loss in different cities are different. Conclusion: All prefectures and cities should formulate specific policies and measures according to the actual situation and local conditions, continuously optimize the input structure of production factors, improve the technical service system of the modern forestry industry, intensify the application of new scientific and technological products, and further improve the value realization efficiency through technological progress and management innovation, providing a demonstration model for the areas rich in forest resources.

Objective: The paper is intended to study the spatial-temporal evolution and patterns of abrupt changes of vegetation NPP during the key implementation period of ecological conservation and restoration (2000-2020) in Heilongjiang Province, and to provide a scientific basis for ecological environment management, policy formulation, and the realization of "Carbon Peaking and carbon neutrality" in China in the future. Method: Based on the validated TEC model and China GlobeLand30 land cover data set(2000, 2010, 2020), Sen estimation method, M-K and T-test method were used to study the spatial-temporal evolution and patterns of abrupt changes of NPP from 2000 to 2020. Spatial superposition analysis was used to output land cover type transfer matrix to explore the effects of national ecological restoration projects on NPP. Result: 1) The average values of annual NPP significantly increased (P < 0.01). The growth rate of NPP increased significantly after 2010 and reached a new high in 2020. 2) NPP abrupt change was widely distributed in a phased manner and peaked in 2010. The high frequency stage and peak time of NPP abrupt change are highly consistent with the key nodes of China's major ecological protection and restoration projects. In general, ZZ pattern (increasing trend before and after abrupt changes) was the most obvious pattern of NPP abrupt changes in Heilongjiang Province. However, forest of FZ pattern (decreasing trend before abrupt change, increasing trend after abrupt change) showed the highest proportion in area indicating significant achievement of the ecological restoration. After 2010, the proportion of areas with forward abrupt change to total area with abrupt changes (ZZ and FZ patterns) stabilized, accounting for more than 96.9% on a yearly basis. 3) Forest, farmland and grassland are the top three ecosystems in average annual total NPP in Heilongjiang Province from 2000 to 2020. As NPP of the farmland rose rapidly, proportion of farmland NPP to regional total NPP in Heilongjiang Province increased significantly (P < 0.01). 4) From 2000 to 2010 and from 2010 to 2020, ecological protection and restoration projects directly contributed 56.8% and 33.2% to NPP changes in this region, respectively. Conclusion: It can be seen that Heilongjiang province still shows the continuous enhancement of vegetation carbon sequestration capacity on the basis of the original strong carbon storage from 2000 to 2020. In the future, more attention should be paid to carbon sequestration potential and carbon sequestration methods in agriculture. Ecological conservation and restoration projects have had an important impact on NPP. Heilongjiang Province will have a huge vegetation carbon sequestration capacity and play an important role in global and regional carbon balance under the background of major ecological projects in Northeast Forest Belt and global warming.

Objective: This study is intended to investigate the effect of planting Stropharia rugosoannulata under Larix gmelinii and Betula platyphylla forests on the flammability of litter layer in the Greater Khingan, and to develop a method to combine forest fire prevention with underforest economy. Method: After the period of forest fire prevention, a stand of 2 500 m² was set up in each of the L. gmelinii and the B. platyphylla forests of Zhuangzhi forest farm of Songling Forestry Bureau in June 2020, and 12 sample quadrats of 70 cm×70 cm were set up in each stand (2 stands, canopy density about 0.7). The litter was used as the cultivation substrate to plant S. rugosoannulata. Four densities of the control (0 bags), low (2 bags), medium (4 bags), and high (6 bags) were set up according to the number of fungus bags planted in each quadrat. After mushroom harvesting, the litter samples were collected and taken back to the laboratory for thermogravimetric experiments, the calorific value and ignition point were measured, and the thermogravimetric indicators of holocellulose and lignin such as thermal weight loss proportion, weight loss ratio and thermal degradation kinetics were analyzed. Meanwhile, we calculated and compared the difference in flammability index and comprehensive burning index. Result: The activation energy and calorific value of holocellulose in litter under L. gmelinii forest decreased with the increase of planting density of S. rugosoannulata, and were lower in medium and high densities, in which the activation energy of holocellulose decreased by 36.39% and 35.07%, respectively, and the calorific value decreased by 74.21% and 76.81%, respectively. The activation energy of holocellulose of litter under B. platyphylla forest decreased significantly under medium and high density (P < 0.05), it was the lowest at low density, which decreased by 32.97%. The trend of calorific value was consistent with the litter of L. gmelinii forest, which was still lower under medium and high densities, and decreased by 78.75% and 72.07%, respectively. Conclusion: Underforest planting of S. rugosoannulata had the effect of reducing the comprehensive burning index of the litter in L. gmelinii forest and B. platyphylla forest, the litter planting with medium and high density S. rugosoannulata had the better effect in reducing the comprehensive burning index, and the comprehensive burning index of litter under the medium and high planting density in L. gmelinii forest decreased by 86.74% and 87.51%, respectively, and the comprehensive burning index of litter under the medium and high planting density in B. platyphylla forest decreased by 93.63% and 91.52%, respectively. Future study can explore the optimal planting density with both fire prevention benefit and mushroom yields.

Objective: This study was designed to comprehensively analyze the relationship between Hawthorn distribution and environmental factors, and to provide a theoretical basis for the protection and utilization of Hawthorn resources. Method: Based on the data of 192 geographical distribution points and 20 environmental variables downloaded from Worldclim from 1970 to 2000, the potential suitable growth area of Hawthorn in 2020 was predicted using the MaxEnt model, and the suitability grades was classified. At the same time, the key environmental factors affecting the distribution were analyzed. Result: The analysis showed that the prediction of MaxEnt is accurate, and the AUC values of both test data set and training data set are more than 0.9. Nine environmental factors such as precipitation of warmest quarter (28.6% contribution), temperature seasonality standard deviation (27.2%), mean temperature of driest quarter (13%), maximum temperature of warmest month (11.8%), annual precipitation (10%), altitude (7.7%), mean diurnal range (1.2%), precipitation seasonality coefficient of variation(0.4%)and isothermality(0.2%) are the key environmental factors that affect the distribution of Hawthorn. The total suitable area of Hawthorn in China has reached 2 487 002 km², which is mainly distributed in North, Northeast and East China. The top 10 provinces account for 82.38% of the total suitable area. Shandong, Hebei, Liaoning, Henan, and Shanxi Provinces have the largest area, with a total of 481 519 km², accounting for 82.56% of all highly suitable areas. Jiangsu, Shaanxi, Beijing, Tianjin, Heilongjiang, Jilin, and Inner Mongolia have great potential for development. Conclusion: The suitable growing area of Hawthorn is highly concentrated, and the suitability decreases gradually from the Bohai Rim to the inland provinces, among which Shandong, Hebei, Liaoning, Henan, and Shanxi are the core areas suitable for Hawthorn cultivation.

Objective: Ziziphus jujuba is a tree species with both ecological and economic benefits and has been successfully introduced to Xinjiang, China over the last two decades. Management of forest water consumption in arid zones requires estimations of evapotranspiration, which this study aimed to address through the use of the SIMDual-Kc model. Method: The model was parameterized and its applicability to dryland plantation economic forests was verified through measures of evapotranspiration and plant transpiration rate by two-year eddy covariance and a pin-stem flow meter, respectively. Evapotranspiration and plant transpiration were simulated under different irrigation frequencies, preset according to the 2-year measured data. Result: The SIMDual_Kc model was able to provide estimates of evapotranspiration and plant transpiration during the reproductive period that showed good consistency with measured data. When compared against measured data, the model simulations of evapotranspiration obtained determination coefficient (R²), index of agreement (d), Nash Sutcliffe Efficiency (NSE), and Standard Deviation Ratio (RSR) goodness-of-fit values of 0.57-0.60, 0.86-0.87, 0.51-0.55, and 0.67-0.70, respectively, whereas those of simulated plant transpiration were 0.73-0.77, 0.91-0.92, 0.62-0.64, and 0.60-0.61, respectively. The parameters of the SIMDual-Kc model were: Basalt crop coefficient K_{cb ini} = 0.18, K_{cb mid} = 0.7, K_{cb end} = 0.7, Depth of evaporation layer Z_e = 0.15 m, Total evaporation water TEW = 18 mm, Readily evaporable water REW = 19 mm, and Soil water consumption ratio P = 0.5. Model scenario analysis showed that under a constant total irrigation depth, different irrigation frequencies had greater and smaller effects on soil evaporation and plant transpiration, respectively and soil evapotranspiration increased with increasing irrigation frequency, indicating that soil surface water content had a greater effect on soil evapotranspiration. Conclusion: The SIMDual-Kc model provided accurate estimates of evapotranspiration and plant transpiration of planted Jujube forests in arid zones. The result of this study can provide a theoretical basis for formulating reasonable drip irrigation systems, irrigation decisions, and for agricultural water conservation in arid zones.

Objective: To study the effects of different ectomycorrhizal fungi inoculation under drought stress on the root growth, root exudates and rhizosphere soil enzyme activities of Pinus massoniana seedlings, and to understand the strategies of different ectomycorrhizal fungi to promote growth and resist stress. Method: With the pot experiment in the greenhouse and two conditions of normal watering and drought stress, the difference in growth of above and below ground, root exudates and rhizosphere soil enzyme activities of different Pinus massoniana seedlings that respectively inoculated of Suillus placidus (Sp), Scleroderma citrinum (Sc) and uninoculated (CK) were studied. Result: 1) Drought stress inhibited growth and root vitality of P. massoniana seedlings, but Sc and Sp inoculation promoted seedling growth, biomass accumulation and root vitality, and also improved root morphology, with better performances in Sc inoculation seedlings. 2) A total of 6 types of organic substances, including acids, ketones, terpenoids, esters, alcohols and aldehydes, were detected in the root exudates, with a total of 28 compounds. The composition and relative content of secretions were regulated by inoculation and drought stress. Sc inoculation can increased the types of exudates while Sp inoculation decreased that; Drought stress increased the types of exudates and was not affected by inoculation; The relative content of various exudates responds obviously and differently to drought and inoculation treatments, and the change trends were related to the types of exudates. At the same time, the two ectomycorrhizal fungi also changed the relative content of various secretions under drought stress, mainly in inhibiting of the relative content of terpenoids, increasing of the relative content of aldehydes, and decreasing more in the relative content of acids. The effects of the two ectomycorrhizal fungi on the relative content of different compounds of the same component were also significantly different. 3) Sp inoculation treatment promoted plant growth and resists drought stress by increasing rhizosphere soil urease and invertase, while Sc treatment resisted drought stress by maintaining higher acid phosphatase and urease activities. Conclusion: Inoculation of Sp and Sc promoted the growth of P. massoniana and alleviate drought stress by improving root morphology, increasing root vitality and maintaining higher soil enzyme activities. Sc inoculation had the best effect on alleviating drought stress. Root traits and their changes under drought stress were complex and different after different mycorrhizal fungi inoculation. This is of great significance for understanding the mechanism of mycorrhizal fungi regulating root exudates in response to drought stress.

Objective: This study aims to investigate the biological characteristics of root border cells of Cunninghamia lanceolata and their response to aluminum stress, which could provide important basis for elucidation of response to aluminum stress and selection of aluminum-tolerant germplasms in C. lanceolata. Method: In this study, seeds of C. lanceolata were germinated through aeroponic culture methid. The biological characteristics of root border cells were investigated with the seedlings of C. lanceolata. The response of root border cells to aluminum stress was also surveyed by aluminum ion treatment. Result: It was found that the root tip began to be produced root border cells when the seeds just germinated, and the number of root border cells gradually increased with the elongation of the roots. When the root length was 1.5 cm, the number of root border cells reached the maximum (about 7 497 in average). The cell activity test showed that when the root length was less than 0.5 cm, the activity of root border cells could reach 95%. With the elongation of roots, the activity of root border cells decreased gradually, but basically stabilized around 80%.During the development of root border cells, the activity of pectin methylesterase (PME) in root cap showed its highest level when root length less than 0.5 cm, and then decreased with the root elongation. And, further EGCG treatment indicated that the PME activity was not required for the formation of root border cells but rather related to their spatial separation. The results of aluminum stress showed that Al³⁺ was able to significantly inhibit the root elongation of C. lanceolata seedlings, and this inhibition effect was more obvious after removal of the root border cells. Low concentration of Al³⁺ (100-200 μmol·L^-1) promoted root border cells to secrete more mucilage and form a thicker mucilage layer, which prevented Al³⁺ from adsorbing to the root tips and thus played a protective role for the root tips. Conclusion: The root tips of C. lanceolata seedlings can produce a great number of living root border cells, and the process of their separation into the rhizosphere might be mainly regulated by PME. In response to aluminum stress, these root border cells will secrete more mucilage to reduce aluminum toxicity or protect the root tips of C. lanceolata seedlings from aluminum toxicity.

Objective: In this study, effects of long-term combined application of organic and inorganic fertilizers on soil carbon and nitrogen fixing microorganisms in Moso bamboo forests were investigated in order to provide theoretical basis for maintaining and improving soil fertility. Method: Soil samples were collected from surface (0 - 20 cm) and subsurface (20 - 40 cm) soil layers in moso bamboo forests intensively managed for 0(CK), 6, 10, 15, and 20 years. The fluorescence quantitative PCR (q-PCR), terminal restriction fragment length polymorphism (T-RFLP), and clone library of the cbbL and nifH genes, combined with redundancy analysis (RDA), were used to detect the differences in the community structure of CO₂- and N₂-fixing bacteria over time and reveal the effects of long-term combined application of organic and inorganic fertilizers on soil carbon and nitrogen fixation microbial community structure of Moso bamboo forests. Result: 1) The intensive management practice enhanced SOC and soil available N and K contents during 20 years, although they fluctuated during the process. The soil pH was generally stable between 5.0 and 5.5. 2) Compared with CK, the abundance of gene cbbL in topsoil decreased significantly at IM6 (P < 0.05), and then gradually recovered to the level of CK at IM20, while the abundance of gene nifH in management treatments was significantly decreased compared with CK (P < 0.05). Shannon index and evenness index of CO₂- and N₂-fixing bacteria decreased significantly after 10 years of management and increased significantly after 20 years of management (P < 0.05). The community structure of CO₂-fixing bacteria in CK was significantly different from that of all management treatments, while N₂- fixing bacterial community structure at IM20 was similar to that of CK. 3) Phylogenetic analysis showed that the dominant groups of CO₂- fixing microbials were Bradyrhizobium sp., Rhodospirillum centenum, Thioflavicoccus mobilis, Stappia meyerae, Mesorhizobium ciceri, and Starkeya novella, which all belonged to Proteobacteria, and the dominant group of N₂- fixing bacteria was Rhizobiales. 4) The community composition of CO₂- fixing bacteria was significantly correlated with contents of available phosphorus (AP) and NH₄⁺-N, and the change of δ¹³C. The community composition of N₂- fixing bacteria was significantly correlated with the changes of soil organic carbon (SOC), available phosphorus (AP), available potassium (AK), alkalytic nitrogen (N), NO₃^--N and C∶N. Conclusion: The long-term combined application of organic and inorganic fertilizer in Moso bamboo forests improves the soil nutrient content without causing soil acidification, which plays a positive role in improving the soil physicochemical properties. The changes in soil nutrient caused by the application of mineral fertilizer combined with manure is an important factor driving the changes of abundance, diversity and community structure of CO₂ -and N₂-fixing bacteria in the soil of Moso bamboo forests.

Objective: Bamboo is a facultative reproductive plant, with a large number of varieties and variants. Are there differences in chromosome number and structure among these bamboos? To solve these problems, the distribution characteristics of 45S rDNA and 5S rDNA of 12 different bamboo species was studied, meanwhile its chromosome number and structure was revealed, in order to provide corresponding chromosome physical markers for related chromosome recognition. Method: In this study, Phyllostachys edulis, P. edulis 'Tao kiang', P. edulis 'Heterocycla', P. violascens, P. aureosulcata 'Spectabilis', P. dulcis, P. nigra, P. reticulata 'Lacrima-deae', P. vivax f. aureocaulis, P. aurea, Pleioblastus gramineus and Pseudoasa amabilis were selected as materials, and 45S rDNA and 5S rDNA were used as probe. The distribution of 45S rDNA and 5S rDNA on the chromosomes of the 12 different bamboo species was studied by the two-color fluorescence in situ hybridization. Result: 1) The chromosome number of 12 bamboo species was 2 n=48, and their 45S rDNA distribution on the chromosomes showed a certain diversity. ①There were two 45S rDNA sites on the chromosome of P. edulis, P. edulis 'Tao kiang', P. edulis 'Heterocycla', P. violascens, P. vivax f. aureocaulis and P. reticulata 'Lacrima-deae', respectively, these 45S rDNA sites were consistent in distribution position and signal strength. ②There were also two 45S rDNA sites on the chromosomes of P. amabilis, P. aurea, P. dulcis and P. aureosulcata 'Spectabilis', but one of them was stable, located at the end of the chromosome, and the other site was seriously broken and often separated from the distribution position. ③Although P. nigra and P. gramineus also had two 45S rDNA sites, these two 45S rDNA differed greatly in signal strength, especially P. nigra, showing more obvious. 2) The 5S rDNA also showed a certain polymorphism distribution on the chromosomes of 12 bamboo species. ① P. edulis, P. edulis 'Tao kiang' and P. edulis 'Heterocycla' had similar 5S rDNA distribution with two pairs of 5S rDNA sites, of which one pair had strong signals and was located at the end of the chromosome, and another pair with weak signals was located near the middle region of the chromosome. ②P. violascens, P. dulcis and P. vivax f. aureocaulis had similar 5S rDNA distribution pattern, two pairs of 5S rDNA with similar fluorescence intensity were located near the middle region of the homologous chromosomes in pair. ③The distribution pattern of 5S rDNA of P. aureosulcata 'Spectabilis', P. nigra and P. gramineus was special, with three asymmetry 5S rDNA sites. As for P. nigra, two 5S rDNA sites were located at the end of chromosome in pair and another one was located near the middle region of a chromosome region alone. As for P. aureosulcata 'Spectabilis', two different 5S rDNA sites were located near the middle region of the chromosome, and another one was located at the end of chromosome alone. However, three 5S rDNA sites of P gramineus were all located near the middle region of the chromosome. ④The 5S rDNA distribution of P. reticulata 'Lacrima-deae' and P. aurea was similar, with two pairs of weak 5S rDNA signal sites that were located near the middle region of the chromosome. ⑤P. amabilis had a pair of 5S rDNA sites with weak signal, which were located near the centromere region of short arm of the chromosome. Conclusion: 1) According to the distribution characteristics of 45S rDNA and 5S rDNA of the chromosomes of P. aureosulcata 'Spectabilis', P. nigra, P. aurea, P. dulcis, P. gramineus and P. amabilis, we speculate that these bamboo species may have undergone chromosome rearrangement such as fracture, translocation, deletion or insertion. 2) P. edulis, P. edulis 'Tao kiang' and P. edulis 'Heterocycla'have similar 45S rDNA and 5S rDNA distribution pattern, which is consistent with their phylogenesis classification result.

Objective: In this paper we investigated the effect of soil testing and formula fertilization technology on the application of chemical fertilizer in economic forest, and further analyzed the mechanism and different impact of farmers' training on the adoption of soil testing and formula fertilization technology, in order to explore effective method to promote soil testing and formula fertilization technology. Method: Based on theoretical analyses, and the survey data from 314 farmers in 10 counties of Zhejiang Province in 2018, an empirical analysis was conducted with the method of Propensity Score Matching (PSM). Result: Result showed that soil testing and formula fertilization technology significantly reduced the application of chemical fertilizer about 271.65 kg·hm^-2, with the supplement of soil nutrient and chemical fertilizer quality information. The training significantly improved the adoption of soil testing and formula fertilization technology by 15%, by providing more technical information. However, the effect of training varied with different training method. For example, professional training was able to significantly increase the adoption by 10%. The training subjects with strong trust was able to effectively spread technical information, but the training effect was weakened when controlling the subject preference. Both of the training method, the guidance for theory and practice, and self-learning theory, was able to help farmers master technical information. Nevertheless, the training was still effective when taking preference into consideration. Conclusion: The soil testing and formula fertilization technology can reduce the application of chemical fertilizer, and training can relieve the problem of insufficient information during the adoption. To promote green production, we need to pay attention to technology promotion and information transmission.

Objective: The aims of this study are to determine whether the content of tea saponin among Camellia oleifera resistant clones affect the composition of C. sinensis' gut microbiota, and their survival rates, and further to clarify the role of tea saponin on C. sinensis resistance, so as to provide theoretical support for the selection and breeding of C. sinensis resistant varieties and the development of new green prevention and control techniques against C. chinensis. Method: C. chinensis was inoculated into five C. oleifera clones with different content of tea saponin. After larvae matured, the survival of larvae on different clones was calculated and the correlation between the larvae survival rate and the content of tea saponin was analyzed. Sequence obtained from 16S rRNA region was used to compare and evaluate the effects of C. oleifera clones on taxonomic composition, alpha diversity, beta diversity and marker species of gut microbiota. Result: The correlative regression analysis showed that the correlation between the survival of C. chinensis and the content of tea saponin was y = 0.252 5x² - 10.096x +107.47 (R² = 0.718 9). The survived number of C. chinensis decreased with the increase of tea saponin content. Through the analysis of the gut microbiota structure of C.chinensis, it was found that alpha and beta diversities of C. chinensis gut microbiota in Changlin 166, and 40 clones with higher content of tea saponin were significantly different from those in Changlin 55, 53 and 3 clones (P < 0.05). The result of marker species analysis showed that 51 differential OTUs were significantly enriched in the gut of C. chinensis with higher tea saponin group, residing in the genera of Flavobacterium, Azospirillum, Crolobacter, Pseudomonas and Acintobacter, and the last two genera accounted for the highest proportion. Conclusion: Colones with high content of tea saponin can significantly affect survival of C. chinensis, its gut microbiota diversity, and microbial composition. The tea saponin content can be considered as an important chemical index for the breeding of insect resistant varieties for C. oleifera.

Objective: This study aims to provide a basis for scientific control, especially for biological control of Monochamus saltuarius, a newly discovered vector of Bursaphelenchus xylophilus in Liaoning Province, by investigating the damage characteristics of M. saltuarius. Method: Pinus koraiens trees infected by M. saltuarius were cut down and sawn into one-meter long segments from the base of the trunk. The bark was peeled off to record the number of invasion holes of M. saltuarius, then the wood segments were dissected to record the number of larvae. The diameter and water content of the wood segments were measured. The relationship between the number of invasion holes, the number of larvae and the height of the trunk were analyzed. The relationship model between the number of larvae and the diameter and water content of the trunk was established. Result: The results showed that the invasive holes of M. saltuarius mainly distributed in the trunk of 1-7 m above the ground. The number of invasive holes in the trunk of 6-7 m was the largest, with an average of 67.72 holes ·m^-1, which was significantly different from the number of invasive holes in 0-1 m and 9-10 m. With the trunk height increased, the number of invading holes in the trunk of 7-13 m decreased first and then tended to stable. The larvae mainly distributed in the part of the tree trunk below 7 m height, and the number of larval at the trunk of 3-4 m was the largest (average 38.29 heads ·m^-1). Larvae were relatively few above 9 m of the trunk, with an average of 11.50 heads ·m^-1. The number of larvae in the trunk of 1-7 m was significantly different from the number of larvae within 9-13 m. The analysis results showed that the relationship between the number of larvae and diameter of logs was conformed to the model y=0.358 7x+6.115 4, and the relationship between the number of larvae and water content of logs was conformed to the model y=-74.155x2+96.209x. Conclusion: With the increase of the trunk height, the number of invasion holes of M. saltuarius increases first and then decreases, while the number of larvae generally decreases, and the number of larvae in the trunk is about 50% of the number of invasion holes. The correlation between the number of larvae and diameter of wood segments, and the correlation between the number of larvae and water content of wood segments were clarified. The results provide a basis for predicting the number of M. saltuarius in the trunk of P. koraiens, and then predicting the population density of M. saltuarius in the epidemic area, which could provide a reference for the scientific control of M. saltuarius that spreads Bursaphelenchus xylophilus.

Objective: Accurately identifying the intensity difference, variation trend and inter-annual variation of forest pest disasters in different periods in China is the premise for formulating effective forest pest disaster response strategies and implementing differentiated fiscal subsidy policies. It is of great significance to prevent forestry disaster risk, improve the risk control level of forest resources and enhance the supply capacity of forestry carbon sink. Method: The numerical analysis method was used to analyze the general occurance of forest biohazards with the statistical data of forest biohazards from 1998 to 2018. According to the variation values of the incidence of forest diseases, insect pests and rodent disasters in China from 1998 to 2018, the interannual changes of the intensity of various disasters were analyzed. The grey correlation degree method was further used to determine the correlation degree of forest diseases, insect pests and rodents in forestry pest disasters and the weight of their impact on forest resources, and hence to determine the comprehensive index of forest pest disasters in China from 1998 to 2018. Finally, the comprehensive grade of forest pest disasters in China in the above period was divided. Result: 1) From 1998 to 2018, insect pests was the main forest pest disaster in China, followed by disease and rodent. However, the increase of the area of rodents infestation was larger than that of diseases and insect pests.Compared with 1998, the growth rate of the area affected by rodents, diseases and insect pests in 2018 increased by 156.36, 83.09 and 57.72 percentage points, respectively. 2) The intensity of all kinds of forest pest disasters was different in different years. In the study period, 2007 was the year with the highest occurrence intensity of forest pests and rodents, while 2018 was the year with the highest occurrence intensity of forest diseases. 3) According to the comprehensive disaster index of forest pests from 1998 to 2018, the forest pest disaster in China from 1998 to 2018 can be divided into three stages. The first stage was from 1998 to 2005, during which the comprehensive disaster level of forest pest was the lowest, and the harm of forest pest to forest resources was the least. The second stage was from 2006 to 2008, during which the forest pest caused the most serious damage to forest resources, and the comprehensive disaster grade was the highest, especially in 2007. The third stage was from 2009 to 2018. In this stage, the comprehensive level of disaster to some extent decreased, but the overall degree of disaster was still relatively serious. Conclusion: From 1998 to 2018, the total area of forestry pest disasters in China is on increase. Among them, the mild disasters account for the majority, but their area is increasing year by year, while the area and incidence of moderate and severe disasters fluctuate and decrease. The annual area of forest insect pests is relatively serious, and the area of rodent pests is increasing rapidly. At present, forest disasters have reached the highest disaster intensity in the research period. In addition, although the comprehensive level of forest pest disaster has declined, it is still at a relatively high level, and the area of pest disasters is increasing year by year, and the prevention and control situation is still serious. It may be effective to maintain the ecological security and promote the construction of ecological civilization in China by adopting differentiated forest disaster response measures, focusing on curbing the rapid growth trend of forest rodent pests, reducing the incidence of forest insect pests and strengthening the prevention and control of severe diseases.

As a new plant hormone, brassinolide (BR) has been widely used in agriculture and forestry due to its advantages of high efficiency, environmental protection and wide spectrum. BR can promote the elongation and division of plant cells, enhance the photosynthetic capacity of leaves, and regulate the development of roots, thereby improving plant growth and development, and increasing the yield. BR significantly affects the reproductive growth of plants, by regulating the flowering time of plants, prolonging the flowering period, and increasing the number of flowers. However, a few studies have pointed out that BR has an inhibitory effect on flowering. BR could promote the fruit setting and improve the seed and fruit quality. After the plants are subjected to external stress, the antioxidant system of plants is damaged, and the growth and development of plants are retarded. Spraying BR could increase the activity of antioxidant enzymes, reduce the content of malondialdehyde, and enhance the stress resistance of plants. With the innovation of research method and facilities, the mechanism of BR signal transduction, and the functions and mechanisms of BR-related genes are revealed. BR signal transduction is regulated by kinases, receptor proteins, transcription factors and other elements. BRI1/BAK1 can recognize BR molecules on the surface of cell membrane. Under the action of protein kinases (BSK1, BSU1, BIN2, CDG1), transcription factors (BZR1, BES1) are activated to regulate the expression of BR responsive genes. Genes related to BR biosynthesis and signal transduction, such as DAS5, DET2, DWF4, CPD and BAK1 have been identified, cloned, and transformed into different species using transgenic technology, which could improve the growth of transgenic plants and enhance the resistance of plants to adversity. This paper reviews the research progress in the fields of BR regulation of plant vegetative and reproductive growth, the enhancement of plant stress tolerance, and molecular mechanism of BR, discusses the existing problems in BR research, and prospectes the future research direction of BR.

Objective: The main purpose of this paper is to study the reasons that seven plants, including Metasequoia glyptostroboides, Liquidambar formosana, Broussonetia papyrifera, Populus tomentosa, Chaenomeles sinensis, Liriodendron chinense and Fraxinus chinensis do not become the hosts of Corythucha ciliata although the volatiles from the leaves of these seven plants have a significant attracting effect on C. ciliata adults, soas to provide a basis information for the use of non-host plants by tree species arrangement or their extracts to prevent and control C. ciliate. Method: The crude extracts from the leaves of the seven non host plants were obtained by grinding and filtration. The crude extracts were fed to the adults of C. ciliata to determine the impact on their survival. The crude extracts and dilutions of different volume fraction were applied to the leaves of Platanus acerifolia to determine the repellent activity against the adults of C. ciliata. Result: The survival status of C. ciliata adults fed with crude leaf extracts of 7 non-host plants was significantly lower than the control (water), and the median lethal time, 99% lethal time and average survival time were extremely significant shorter than those of C.ciliata adults treated with water, especially C. sinensis. The crude extracts from the leaves of the seven non-host plants all have repellent effects on C. ciliata adults. The highest repellent rate was B. papyrifera (74.84%), followed by F. chinensis (70.74%), L. formosana (53.90%), C. sinensis (53.33%), M. glyptostroboides (51.66%), P. tomentosa (49.47%) and L. chinense (43.19%). When the crude extracts were diluted, the repellent effects decreased, but the effects did not decrease unidirectionally with the decrease in volume fraction. Conclusion: That the crude extracts of these seven non-plant which have an attractive olfactory effect, contain substances that are toxic or and repellent to the adults of C. ciliata, may be one of the reasons why these plants are not used by C. ciliata. Among the seven plants, the extracts of B. papyrifera had the strongest repelling effect and the extracts of C. sinensis have the greatest toxicity to C. ciliata. The possible applications of the two plants in the control of C. ciliata can be studied further.