By collecting data from published literature on biomass measurements of Cunninghamia lanceolata forests, we explored the variation and its determinants of three common biomass estimation factors, i.e. biomass conversion and expansion factor (BCEF), biomass expansion factor (BEF), and root:shoot ratio (R). Means of BCEF, BEF and R were 0.616 Mg·m^-3 (n=245, SD=0.426), 1.489 (n=334, SD=0.379) and 0.247 (n=268, SD=0.083), respectively. All biomass estimation factors decreased and then leveled off (P<0.001) with increasing stand age and tree size (mean diameter at breast height, mean tree height, and standing volume), while they increased with increasing stand density (P<0.001). Values of BEF and R decreased significantly with increasing mean annual temperature (P<0.05), while BCEF values did not show the changing trends. With increasing mean annual precipitation, values of BCEF and R had no changing trends, but BEF values decreased and then increased above 1 550 mm (P<0.001). Therefore, stand and climatic variables should be considered when applying BEF and R to estimate forest biomass across broad climatic gradients, especially with BEF.

In this study, forest carbon stock and its spatial distribution of Xianju County, Zhejiang, were simulated by using a sequential Gaussian co-simulation algorithm based on data, collected in a forest resource inventory from sample plots in 2008, and the Landsat Thematic Mapper^TM image. The obtained forest carbon map was assessed using three accuracy measures of overall estimate consistency (OEC), average coefficient of variation (ACV), and relative root mean square error (RRMSE). Moreover, temporary sample plots were selected surrounding the permanent sample plots and the data were collected. The permanent and temporary plot data sets were respectively combined with the TM image to scale up forest carbon stock from a spatial resolution of 30 m × 30 m to 1 km × 1 km using a sequential Gaussian block co-simulation algorithm. The up-scaled map from the temporary plot data were used to assess the accuracy of the corresponding map from the permanent plot data and to analyze their spatial representatives. The results showed that the 2008's forest carbon stock estimated for the county was 2 667 878 Mg. Most of the stock was found in the southern and northern mountainous areas and less amount of the stock in the central west to the east narrow areas that had lower elevation. The forest carbon density varied from 0 to 65.7 Mg·hm^-2. Whether all the permanent plots or half of them were used, the population estimates of forest carbon fell into the confidence intervals of the plot data at a significant level of 5%. When the data from the permanent sample plots were compared with those from the temporary plots, the coefficient of correlation for carbon density was 0.95 and 0.85 at the spatial resolutions of 30 m × 30 m and 1 km × 1 km, respectively. This result implied that when forest carbon stock was scaled up from a spatial resolution of 30 m × 30 m to 1 km × 1 km, the obtained map using the permanent plots re-produced the spatial distribution of the forest carbon density very well. In addition, if a cost efficiency was defined as (1-RRMSE)/number of sample plots, using half of the sample plots showed a higher cost efficiency than using all the sample plots, implying this cost efficiency indicator can be used to determine an appropriate number of field plots in sampling design for generating spatial distribution of forest carbon stock.

Abstract: The tree-ring structure, including tree-ring width, earlywood width and latewood width, of Chestnut trees (Castanea mollisima) in Beijing area was investigated to establish the standardized chronologies (STD) and residual chronologies (RES). The relationships between chestnut radial growth and climate factors, and the radial growth response to the climatic condition were analyzed to screen the climatic factors that could be used for climate reconstruction in Beijing area. Results showed that chronologies of ring width and latewood width had better quality than that of earlywood width. RES were superior to STD, and its overall sample representative reached 93% and the first principal component could explain 40% of variance. The correlation analysis and response analysis indicated that the responses of ring width, earlywood width and latewood width to climate factors were different. This study suggests that in the future climatic reconstruction, different tree-ring structure indicators should be used to reconstruct different climate factors. Specifically, the tree-ring width and latewood width could be utilized for the reconstruction of temperature in June, the latewood width could be utilized for the reconstruction of precipitation in July, and the earlywood width could be used for the reconstruction of temperature in March and April.

In order to investigate the photosynthetic characteristics of cortex of Salix matsudana branches, this study measured the photosynthetic pigment content of current year branches and fully expanded leaves of S. matsudana cultured in artificial climate chamber. The two kinds of chloroplasts were isolated by sucrose density gradient centrifugation, and their intact rate was measured and their differences between light response characteristics and chlorophyll fluorescence characteristics were analyzed comparatively. The result showed that the chlorophyll content and carotenoid content of the cortex were approximately 10.0% and 13.7% of that from the leaf, respectively. The ratio of chlorophyll-a to chlorophyll-b in the cortex was lower than that of the leaf, and the ratio of chlorophyll to carotenoid was conversely. The intact rate of acquired chloroplasts was more than 80%, which was able to meet the needs of research on photosynthetic physiological characteristics of chloroplasts. The rate of photosynthetic oxygen evolution of cortical chloroplasts was lower than that of leaf chloroplasts all the way under the light intensity of 100, 200, 300, 500, 800 μmol·m^-2s^-1, respectively. The light saturation point of cortical chloroplasts was at 300 μmol·m^-2s^-1 with the maximum rate of photosynthetic oxygen evolution of 35.58 μmol·mg^-1 Chl h^-1 while the leaf was at 500 μmol·m^-2s^-1 with the maximum rate of photosynthetic oxygen evolution of 42.78 μmol·mg^-1Chl h^-1, respectively. The maximum photochemical efficiency of PSⅡ(F_v/F_m) of cortical chloroplasts was greater than that of leaf chloroplasts by 30.2% averagely, and the potential photochemical activity of PSⅡ(F_v/F_o) was greater than the leaf chloroplasts by 36.1% averagely. In summary, the photosynthetic rate and light saturation point of cortical chloroplasts of S. matsudana were lower than those of the leaves, however the cortical chloroplast had characteristics such as higher light energy conversion efficiency and lower chlorophyll a/b ratio which was adapted to the light environment within the branches.

Three apple (Malus domestica) cultivars including Fuji, Gala and Golden Delicious were pollinated before the blooming period with pollens from different pollination trees. The ascorbic acid (AsA) metabolism relative enzymes, including ascorbate oxygenase (AAO), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDHAR), L-galactono-1,4-lactone dehydrogenase (GalLDH), L-galactose dehydrogenase (GalDH), in the fruits were determined every 20 days during fruit development stage. The results showed that AsA contents increased significantly during 40–60 days after pollination. The GalLDH activity of the pollinated fruits was significantly higher than that of the control. The GalDH activity of the pollinated fruits was also higher than that of the control even though the enzyme had relatively low activity during fruit development process. The activity of MDHAR and DHAR in the pollinated fruits was relatively higher than the controls during the fruit development stage, while the activity of AAO and APX in the pollinated fruits was lower than the controls, but there were no significant differences in those enzymes activities between the pollinated fruits and the controls. Besides, the activity of AAO, APX, DHAR, and MDHAR maintained a relatively high level at the early fruit development stage, then declined and finally remained stable at a low level. The study suggests that the increase of the synthetase activity leads to the increase of AsA contents in the pollinated fruit.

This work is aimed at understanding important habitat characteristics of the genus Rosa in Xinjiang to provide information for assessment, protection and utilization of wild rose resources. Based on a field investigation and previous published literature, we investigated the geographical and meteorological characteristics of 14 wild Rosa species only or majorly distributed in Xinjiang. Results showed that all investigated Rosa species grew in south slope except R. fedtschenkoana and R. acicularis. Elevation distribution was between 1 000-2 000 m for most of these Rosa species, with R. persica, R. berberifolia and R. laxa distributed at lower than 1 000 m. Based on the data of temperature and rainfall, it was inferred that these Rosa species could tolerate the great fluctuate of annual temperature and drought. Among 14 wild Rosa species, R. albertii had the strongest tolerance to freeze, while R. persica and R. berberifolia had the strongest tolerance to heat. We divided the 14 wild Rosa species into 5 groups according to hierarchical cluster analysis of their associated plants. The group V, including R. persica and R. berberifolia, exhibited great difference from other groups, indicating that its habitat characteristics were different from other Rosa species. Correlation analysis of elevation distribution of these Rosa species revealed that elevation distributions of R. persica and R. berberifolia, R. fedtschenkoana and R. acicularis, as well as R. iliensis and R. schrenkiana were significantly correlated, respectively. We also conducted CCA (Canonical Correspondence Analysis) for R. persica which is valuable in breeding however the distribution area is reduced rapidly. Based on data from 18 sampling fields of 6 major distribution areas, we found that elevation, rainfall and average temperature in July were the major factors determining the distribution of R. persica. In summary, our results provided valuable references to evaluation, protection and application of wild Rosa species which are located in Xinjiang.

HAM (Hairy Meristem) subfamily in GRAS family is a group of transcription factors that play important roles in plant growth and morphogenesis. By using RT-PCR and RACE technique, a HAM homologous gene, DlSCL 6 was cloned from Dendrocalamus latiflorus. This gene has 2 006 bp in full-length including the 5' untranslated region (UTR) of 129 bp, 3' UTR of 266 bp, and coding region of 1 611 bp. DlSCL6 protein has five conserved domains (LHR Ⅰ, VHIID, LHR Ⅱ, PFYRE, and SAM), and is relatively high consistent to SCL6 proteins in some monocots, and some consistent of 43% to the Arabidopsis thaliana. A recombinant protein with approximately 60 kDa was obtained in the expression of this gene in Escherichia coli. The sense transgenic plants derived from ectopic expression of DlSCL 6 in A. thaliana showed prolonged vegetative growth, delayed flowering, and increased rosette leaf number, while the antisense transgenic plants had early flowering and thin plants and significantly reduced rosette leaves number. This study indicates that DlSCL 6 gene can influence the shoot apical meristem status, and hence result in changes in morphogenesis.

In this study, four hybrid hazelnuts (Corylus heterophylla×C. avellana), main cultivars in Xinjiang, named Dawei, Liaozhen7, Yuzhui and Ping'ou15, were used as maternal parent and the hybrid hazels of 1-25,84-102, 85-57,84-5,B-21 as male parents for controlled pollination according to a testcross mating design. The combining ability of the parents was analyzed based on nut characters of intraspecific cross to illuminate the feasibility of hybrid hazelnut pollination tree configuration and the influence of parents on their fruit characters. The results of variance analysis showed that these nut characters of intraspecific crosses displayed significant differences among seven different hybridized combination, but not significant differences between repeated blocks.The general combining ability and the maternal effects were significant, while the special combining ability and the male effects were not significant. These nut characters of intraspecific crosses were mainly controlled by the additive gene effects and affected more by the maternal. Ping'ou15, should be used as a main variety, and further promoted in Xinjiang because of its excellent fruit quality parameters and its better fruit shape. The male parent 84-5 could be regarded as the main pollination cultivars because of the greatest general combining ability of the nut three diameter mean value, fruit weight, kernel rate and the fruit cavity coefficient. Additionally, the shell thickness has a negative effect, which all are conducive to nut economic characters and make it suitable to be used as a pollinating cultivar.

In this study, the suppression subtractive hybridization (SSH) method was employed to screen the differential expressed genes in Amorpha fruticosa roots induced by AMF during the colonization process. The results showed that 47 unigenes were obtained, and 35 of them could be aligned with known function genes in GenBank through Blast. According to GO classified information, Blast annotation and related literatures, the 35 unigenes were assigned into eight categories including stress and defense (24%), substance metabolism (17%), energy metabolism (14%), protein synthesis (11%), signaling (11%), cellular structre/cytoskeleton (11%), transcription related (6%), protein folding and degradation related (6%). Among them, stress and defense genes, and metabolism genes occupied the largest fraction, implying stress and defense related genes and substance metabolism related genes should play an important role in the symbiosis process between A. fruticosa and AMF. These genes are widely involved in the biological process of life activity, thus, the process of AMF and A. fruticosa symbiosis is a system involving a variety of biological activities.

The fungus Pochonia chlamydosporia(previously Verticillilum chlamydosporium), which has high parasitic rate on Meloidogyne incognita eggs, is a promising biological control agent for plant nematodes. The culture medium and condition of liquid fermentation of P. chlamydosporia were optimized with orthogonal design. At meantime, kinetic models of spore output and substrate consumption and amino nitrogen generation were established based on Logistic and Boltzmann Equation of Grow/Sigmoidal model and the parameters of the models were determined by Origin Pro V8.6 software. The results showed that under the culture condition of temperature 28 ℃ and in 500 mL flasks, the optimal fermentation medium and culture condition were obtained, including glucose 15.0 g·L^-1, corn flour 15.0 g·L^-1, soybean powder 20.0 g·L^-1,KH₂PO₄ 0.25 g·L^-1, MgSO₄·7 H₂O 0.25 g·L^-1, inoculum volume 5%(V/V), the best initial pH value 5.0, filling capacity 40%(V/V)and rotational speed 190 r·min^-1. The maximum specific spore growth rate was 0.030 2 h^-1 at 88.1 h, specific reducing sugar consumption rate was 0.033 4 h^-1 at 86.8 h and specific amino nitrogen generation rate was 6.864×10^-4h^-1 at 110.8 h. The model simulation fitted well with the experimental observations, which made it possible to reflect the kinetic characteristics of P.chlamydosporia during the liquid fermentation. These results could be employed for large scale production of P. chlamydosporia.

Antifungal protein AMP produced by Streptomyces purpeofuscus YSSPG3 was purified from the fermentation. In order to reveal the anti-disease mechanism of AMP to hybrid bamboo blight, hybrid bamboo seedlings were treated with different concentrations of antifungal protein by spraying foliage or soaking root, and inoculated with or without Arthrinium phaeospermum. The effects of antifungal protein on disease index, and the major defense-related enzymes activities were investigated. The results showed that disease index of the bamboo seedlings treating with 10 times, 20 times, and 50 times dilution of antifungal protein stock solution (360.56 μg·mL^-1 antifungal protein in the stock solution) was significantly lower than the no-treatment control. After being induced by the antifungal protein, the defense-related enzymes activities of the seedlings, such as superoxide dismutase (SOD), polyphenol oxidase (PPO), peroxidase (POD), catalase (CAT) and phenylalanine ammonialyase (PAL), had different responses to the blight infection. The enzyme activities in the seedling leaves treated with both inducement by the antifungal protein and challenge inoculation with A. phaeospermum had a greater increase than those only treated with inducement. Regardless of challenge inoculation or not, the activities of SOD, PPO, POD, PPO, CAT and PAL in the leaves induced by the antifungal protein had the positive correlations with the concentration of the induced antifungal protein. Amplitude of sequential variation and increment of POD, PPO, CAT activities induced by soaking root was greater than that induced by spraying leaves; There was no significant difference in SOD and PAL between the two inducement methods. The correlation analysis showed that the PPO, POD and CAT activities induced by spraying leaves with antifungal protein had significant correlation with infection index. The SOD and PAL activities induced by soaking root with antifungal protein had significant correlation with infection index. It is suggested that the defense-related enzymes activities might have internal association with infection index.

Gasterophilosis is a significant threat to equids in the desert steppe of Xinjiang, China, where Gasterophilus pecorum (Diptera: Gasterophilidae) is the dominant botfly species. A population analysis was conducted on 195 individual G. pecorum larvae collected from three host species, the Przewalski's horse, the domestic horse and the Asiatic wild ass. The sequence of the maternally inherited mitochondrial cytochrome oxidase subunit I (COI) gene in the 195 G. pecorum larvae was analyzed to assess the population differentiation of G. pecorum, and 57 haplotypes was obtained. High haplotype diversity was observed among G. pecorum populations from all host species, indicating that the G. pecorum infecting one host had multiple maternal ancestors. By using the neighbor joining method, a phylogenetic tree was constructed and consisted of six clades, suggesting a high degree of genetic differentiation. The G. pecorum infecting the three hosts had a low degree of genetic differentiation, and the G. pecorum populations infecting Przewalski's horse and wild ass had the most frequent gene exchanges, indicating that G. pecorum infecting Przewalski's horse were mainly transmitted from the Asiatic wild ass. The infectious period of G. pecorum lagged and the infection prosperous period occurred after the domestic horses left. The study revealed the etiology and the prime of the Gasterophilus infection in Xinjiang, and had important implications for further study of this parasite as well as for the management and conservation of Przewalski's horse.

The phenotypic and genetic variation of nondestructive testing traits among 20 clones of the living trees of Larix kaempferi by using Pilodyn and microsecond timer were studied. Variant analysis revealed that the phenotypic and genetic variation coefficients for SWV(stress wave velocity) were 5.09% and 3.57%, which higher than those of P_s and P_n. The clonal repeatability for the nondestructive testing traits ranged from 0.34 to 0.48 in this study, which meant that variation in nondestructive testing traits of L. kaempferi were controlled genetically at medium level. The correlations between nondestructive testing traits and wood properties were analysed, and the results showed that there were significant negative correlations between P_s, P_n and ring density, early wood density, ring wall thickness to lumen area and early wood wall thickness to lumen area. The SWV had significant negative correlations with ring microfibrillar angle, early wood microfibrillar angle and late wood microfibrillar angle, but had significant positive correlations with ring modulus of elasticity, early wood modulus of elasticity and late wood modulus of elasticity. The results of the multiple regression analysis showed that the top two contribution rates of wood property to the P_s, P_n and SWV were ring density and early wood wall thickness to lumen area, ring density and ring wall thickness to lumen area, and early wood microfibrillar angle and ring modulus of elasticity. Linear regression equations between nondestructive testing traits and corresponding wood properties were constituted, and the results showed that the coefficient of determination of linear regression equation between P_s and ring density (0.340) was slightly smaller than those of P_n (0.360). The coefficients of determination of linear regression equations between SWV and early wood microfibrillar angle, ring modulus of elasticity were 0.348 and 0.316.

Experiments were conducted to compare drying quality of six species of eucalyptus veneer. Industrial veneer roller dryer was adopted and the tree species were Eucalyptus urophylla×E. grandis, E. saligna, E. grandis, E. cloeziana, E. dunnii and E. pellita. The results showed that the tree species influenced veneer drying quality significantly. Based on the final moisture content(MC)and the evenness of MC,drying quality was better for E. pellita, E. urophylla×E. grandis and E. cloeziana, but the final MC of E. dunnii did not meet the MC requirements for the low drying rate. There was no significant difference in checks amount and checks length of veneer of these wood species after drying; based on the distortion of veneer, drying quality was better for E. saligna, E. pellita and E. dunnii; as the increased amount of holes by knot dropping in veneer drying process, drying quality was better for E. urophylla×E. grandis, E. dunnii and E. saligna. In summary, the drying quality of E. pellita, E. urophylla×E. grandis, E. cloeziana and E. saligna veneer could satisfy the requirements of plywood manufacturing, but E. dunnii and E. grandis veneer drying need to be studied further.

The poplar (Populus deltoides cv.I-69/55) wood was treated by high-intensity microwave pretreatment with microwave equipment under different initial wood moisture content, microwave radiation power and microwave radiation time. The results showed the transverse permeability of the poplar wood can be significantly increased by the microwave pretreatment; the wood permeability increased at first and then decreased with increased initial wood moisture content, and which increased with the increase of microwave radiation power and radiation time. Compared with the control group, the 24 h water absorption at atmospheric pressure of microwave pretreated wood simple was increased by around 50%, and the reasonable parameters range for initial wood moisture content, radiation power and radiation time were 25%-65%, 10-20 kW and 60-90 s, respectively. The optimal condition for microwave pretreatment was 56%, 19 kW and 89 s for initial wood moisture content, radiation power and radiation time, respectively. This appropriate microwave pretreatment generates high internal steam pressure, resulting in the rupturing of wood cell pore membranes and ray cells. Therefore, the great increase of permeability in the radial and longitudinal direction can be achieved and created favorable conditions for the fabrication of high value-added functional wood based composites materials.

A method for fast poplar wood liquefaction in phenol by using microwave energy was successfully developed. The optimum conditions for microwave-assisted poplar wood liquefaction in phenol are as follows: moisture content 30%-40%, reaction time 15 min, phenol to wood (P/W) ratio 2.5, wood powder diameter 0.18-0.25 mm, and liquefaction yield 87%. It was proved that microwave improved the liquefaction rate at least 6 times faster than conventional heating. Wood was degraded to low molecular weight substances including alcohols, acids, ether, aldehyde and phenolic compounds. Viscosity of liquefied wood products was remarkably decreased from 8 250 mPa·s to 3 015 mPa·s. And 100 g of liquefied wood reacted with about 2.1 mol of formaldehyde. There were only seven main conpounds, including phenol, 2,3-butanediol, 1,2-propanediol, 2-ethoxy-propane, 1,1-diethoxy-ethane, diisopropyl formal and 12-crown-4 in diethyl ether-soluble portions from liquefied wood products. It was concluded that the reaction mechanism was somewhat different between microwave-assisted and traditional wood phenolation. Cellulose and hemicellulose were firstly degraded into monosaccharides. And monosaccharides could be further cracked into 2, 3- butanediol, 1, 2-propanediol, ethylene glycol and ethanedial, and so on. These substances reacted with each other and converted to 2-ethoxy-propane, 1, 1-diethoxy-ethane, diisopropyl formal and 12-crown-4.

According to ANSYS program and optimizing principle getting at the first order torsional vibration shape function for free plate, the relation between lumber shear modulus and the first-order torsional frequency for the free plate was induced by the method of energy. The correctness of this formula was verified by the three aspects of mathematical simulation of lumber shear modulus, experimental test and static test. Transient excitation method can measure the spectrum of Sitka spruce, domestic Pinus massoniana, Pinus tabulaeformis, Cunninghamia lanceolata and Quercus mongolica wood free plates. With the aid of cross-power spectrum concept from the spectrum diagram we can identify first-order torsional frequency of free plate.

The differences in the terrain and geographic conditions are the important factors resulting in the regional differences in the farmers' input and output of forestland (FIOF). With 1 790 data coming from 8 provinces, by regression models, this paper quantitatively analyzed the impact of the factors on the FIOF, such as the terrain, geographic and other factors. It also analyzed the relations between the FIOF under the influences of these factors. The results showed that: geographically, the rural economic development, the accessibility and the population concentration had significantly affected the FIOF. Topographically,farmer's income of the forestland was significantly affected by terrain conditions, and farmer's income of the forestland in the mountains and hills were significantly higher than in the plains. Among them, the affecting coefficients of the rural economic development,the accessibility and the population concentration on farmer's investment of forestland were 0.128 8, 0.128 7 and 0.162 9. Its affecting coefficients on farmer's income of forestland were 0.152 4, 0.171 8 and 0.198 9. The impacting coefficients of mountainous and hills terrain on farmer's income of forestland were 0.101 9 and 0.016 9.In addition to terrain and geographic conditions, the main source of operating funds, the access to easily apply for timber harvesting indicators, the access to have the product market information services, the access to have financial services, the access to have intermediary services, which had significant impact on the FIOF. Based on these results, the corresponding countermeasures were put forward.

In attempts to foster sustainable forest management practices, households' intentions in choosing different forestry management models have been widely recognized as a core issue in forest management. This paper analyzed the factors influencing households' intention in choosing individual household management, partnership management and joint shareholding management. Based on data collected through a household survey of 842 households in Sanming, Fujian Province, principal component analysis and multinomial logit model were used to analyze the above-mentioned households' intention. Principal component analysis showed that the three factors of the forest management level, policy and logging quota accounted for 72.21% of the total variance. The multinomial logit model exhibited that household's education level, dispersion degree of forestland, difficulty obtaining logging quota, percentage of forestry income in total household income, forestry management level, number of household labor and policy were found to be the main factors influencing choosing the forestry management model. Thus, the government should fully respect farmers' intentions in choosing forestry management model and guide them to choose the suitable management model in local conditions. Further support should be strengthened to promote the overall forestry development.

The genus Juglans (Juglandaceae) consists of about 21 species, which are disjunct groups and distributed mainly in Asia, Europe, and America. The germplasm resources are rich and the varieties are wide in Juglans, which are with long cultivation history. Many species in Juglans are of biological and economical importance because of their high quality timber and nutritious nuts. In this article, the history and progress of molecular phylogeny and biogeography were reviewed. The confused phylogenetic issues were summarized and discussed for Chinese endemic species J. hopeiensis, J. cathayensis, and J. mandshurica, also endangered species of J. cinerea that belongs to section Cardiocaryon. This review made some prospects for future researches on the genetic diversity, origin and distribution, and evolution history in Juglans. With the rapid development of molecular biological technology, the next generation sequencing techniques would be useful tools in studying the phylogeny and biogeography of Juglans (non-model plants).

Variation induced by plant grafting is universal phenomenon, which has been widely used in studies on material transport and flowering regulation and signal transmission mechanism of long distance. In this paper, the reasons of graft-induced genetic variation were analyzed, and three kinds of RNA molecules with long-distance transportability in the grafted plants were emphatically summarized, including exogenous viriods or virus RNA, small non-protein-coding RNA (snRNA) and plant endogenous mRNA. This article systematically reviewed the latest research progress in transfer mechanisms of RNA in grafted plants at home and abroad. This review discussed the future breeding researches by using grafting and the existing problems.

Photosynthetic and growth responses of two-year-old Metasequoia glyptostroboides seedlings to drought following flooding were explored upon simulating water level change in the hydro-fluctuation belt of the Three Gorges Reservoir Area (TGRA). The seedlings were subjected to treatments of six water regimes, including control (C), control followed by drought (CD), continuous half-submersion (HS), half-submersion followed by drought (HSD), continuous full-submersion (FS) and full-submersion followed by drought (FSD). Results showed that net photosynthetic rate (P_n) of M. glyptostroboides seedlings in the HS group (submersion for 60-day) was significantly higher than that in C group. Conversely, a submersion for 120 d, the P_n in HS, and root and total biomass were significantly lower than that in C. However, under drought treatment, the P_n and stomatal conductance (S_c) in CD and HSD were significantly decreased as compared to that in C, while there were no significant differences in P_n and S_c between FSD and C. Similarly, the root and total biomass significantly declined in all of the three drought conditions compared to C. By the end of the recovery period, P_n and S_c of the seedlings under different water stresses were increased to a comparable level as that of C, respectively, except for the P_n in HSD and FS. These results indicated previous flooding had no detectable effect on subsequent sensitivity of M. glyptostroboides seedlings to drought. The M. glyptostroboides showed certain adaptation to the flooding and drought, and thus can be considered as a candidate for the restoration in the hydro-fluctuation belt of the TGRA.

Biomass allocation, photosynthesis and root morphology of Padus maackii one-year-old bare-root seedlings under constant fertilization (CF), exponential fertilization (EF), doubled exponential fertilization (DEF) and no fertilization (CK) regimes were investigated. 1) By the end of the growing season, the root/shoot ratio of seedlings under EF treatment was maximum, and was 6.7%,14.3%,23.1% greater than that with CK, CF and DEF treatment (P<0.05), respectively. 2) The order of seedling height and collar diameter with different fertilization was EF > DEF > CF > CK. Seedling height and collar diameter of EF treatment was 16.6% and 28.1% higher than those of CK, respectively (P<0.05). 3) Tap root length of seedlings under different fertilization treatments was in an order of CK>EF>CF>DEF. The number of first-order lateral root of EF was 19,and more than that with CK,CF,DEF treatment (P<0.05). 4) Photosynthetic rate of EF treatment was 11.66 μmol·m^-2s^-1, and was 17.7% (P<0.05), 7.2% (P<0.05) and 4.2% (P>0.05) greater than that with CK, CF and DEF treatment, respectively. 5) Compared with OF treatment, average length of first-order roots (absorptive roots) under EF and DEF treatment was 15.8%,16.7% higher (P<0.05), respectively; Average diameter of first-order roots under EF and DEF treatment was 5.3%,2.1% greater than that with CF treatment (P>0.05), respectively; Specific root length of first-order root under EF and DEF treatment was 13.9%,14.7% longer than that with CF treatment (P>0.05), respectively. The fifth-order root of EF treatment had greater average length, average diameter and specific root length compared with CF treatment. Exponential fertilization regimes effectively promoted photosynthetic rate and improved root morphology, meanwhile, increased biomass accumulation and nutrient absorption in P. maackii seedlings.

In this study, the trenching method and infrared gas exchange analyzer were used to research the characteristics of soil respiration in 3 different types of stands including coniferous forest, broad-leaved forest and conifer-broadleaved forest in Lanlingxi small watershed in Three Gorges Reservoir Area of China. The results indicated that the annual total soil respiration (R_total), root respiration (R_root), aboveground litter decomposition (R_litter) and soil organic matter (SOM) decomposition (R_SOM) of coniferous forest were 1.61, 0.47, 0.38, 0.76 μmol·m^-2 s^-1, respectively. The annual R_total,R_root,R_litter and R_SOM were 1.47,0.35,0.16,0.96 μmol·m^-2 s^-1 for broad-leaved forest and 2.04,0.76,0.48,0.80 μmol·m^-2 s^-1 for conifer-broadleaved forest, respectively. The respiration rates of soil and its components displayed obvious seasonal dynamics with maximum rate in summer and minimum rate in winter. Soil temperature was the main factor that affected soil and its components respiration rates, and there were significant positive exponential relationships between them (P<0.05). The annual Q₁₀ of R_total,R_root,R_litter and R_SOM were 2.01,1.52,2.73 and 3.03 for coniferous forest,2.51,1.42,3.46,3.08 for broad-leaved forest and 1.86,1.14,3.00,2.32 for conifer-broadleaved forest, respectively. These results suggested that the annual Q₁₀ value of R_root in the three types of stands was significantly lower than that of the total soil respiration and its other components respiration (P<0.05).

Supplementing light in the night can efficiently promote the seedlings growth of Picea crassifolia, but the families genetic variation with supplemental light and the relationship between seedlings growth and mineral elements content were not clear. In this study, we explore the effects of extending lighting time on seedling growth and nutrition absorption, and analyze the response of the family genetic difference to light supplemental. The biomass and mineral element content of nine families from superior trees in P. crassifolia with supplemental light were investigated in growing and bud set period. The results showed that biomass and mineral element content were significantly affected by family, lighting time and interacted by family and lighting time. The biomass of P. crassifolia was increased with supplemental light treatment, and the aboveground biomass and underground biomass were 2.01 and 1.54 times higher than that of the control, respectively. The seedlings with higher growth rate had lower N:P ratio which was mainly affected by the P content. The N:P ratio of seedlings with supplemental light (7.71) was significantly lower than that of the control (9.05) in July. There was a significant negative correlation between the P content and the aboveground biomass. With increased seedling growth promoted by supplemental light, the P content was probably diluted in synthesizing RNA and protein. Thus, it is necessary to apply phosphate fertilizer to seedlings with supplemental light. The family genetic differentiation and phenotypic plasticity to lighting time together brought about the different responses of different families in biomass and nutrient element content to the supplemental light, which makes it possible to select superior family under supplemental light.

Larvae of Melanotus cribricollis (wireworm), one of the most important pests of bamboo at shoot stage in southern China, can be effectively controlled by Metarhizium pingshaense. Compared with many other pests, cuticle of the larva of M. cribricollis is harder and smoother, which makes the infection process of M. pingshaense on M. cribricollis still unclear. In this research, the infection process was studied by observation under scanning electron microscope. The results showed that the conidia of M. pingshaense were mostly found on segmacoria and tips of the foot, secondly on conjunctivum and corrugation on the abdomen, with fewer on the smooth and hard parts. The larvae of M. cribricolli were mostly invaded by germ tube and appressorium of M. pingshaense, and then the mycelia and conidia appeared on the larva body. A germ tube formed at one end of the conidia in 12 h after inoculation. A small part of conidia germinated on the larva body surface while most of conidia penetrated into the larvae by the formed germ tubes in 18 h after inoculation. The germ tubes failed to invade the larvae could form mycelia and grow on surface of the cuticle, and then formed germ tube and appressorium at weak parts. The cuticle penetrated by germtubes or appressoria could be observed at the corrugation parts. The white mycelia firstly appeared at the legsocket of the infected larvae, and the mycelia growing out of the infected larva cuticle began to form new conidiophores and conidia. This study can lay a foundation for research of infection mechanism of M. pingshaense on M. cribricollis.

To understand the structure of insect community and insight into its inner connections, we classified insect communities in Taihu Wetland into different groups based on their taxonomic status and analyzed the relationships of niches between the groups in this study. The results showed that the spatial niche breadth, temporal niche breadth and temporal-spatial niche breadth were obviously different between different groups, indicating the groups fully utilized resources in Taihu Wetland. Among these groups, Hemiptera community had the widest temporal-spatial niche breadth, reflecting Hemiptera insects had the widest distribution and longest activity period; By contrast Dermaptera community had the narrowest temporal-spatial niche breadth, showing Dermaptera insects needed strict habitats and had relatively narrow distribution. Diptera and Coleoptera had relatively large spatial-temporal niche overlap value, which indicated that they had similar unitization of resource and a predator-prey or competitive relationship could be existed between the two groups in Taihu Wetland.