We analyzed the effects of the human being activities on this regions forest based on comparing the biodiversity status of the Changbai Mountain Nature Reserve in 1963 and 2006. We also evaluated the longterm protection effect since establishment of the national nature reserve. Species richness Margalef index, diversity Simposon index and life form spectrum were adopted to analyze the 43year change of plant species composition and plant species diversity in broadleaved and Korean Pine mixed forests on the northfacing slope. The investigations executed in 1963 and 2006 were conducted at the same altitude interval (800～1 000 m). Though the lumber prohibition has been put into practice since establishing the Nature Reserve, we found no significant differences in dominant species composition, Margalef index and Simposon index in the tree layer between the two years. However, human activities under the tree layer were not well controlled. 1) Pineseed collection and trade seriously lessened the Korean Pines seed resources, which would increase the regeneration difficulty of this species. 2) Collecting herbal medicine and gathering the pine seeds disturbed the understory plants growth. The plant species diversity of the herb layer decreased significantly due to the human activities. The proportions of the species number and relative number of chamaephytes and hemicryptophyte species both declined. To prevent the decreasing trend of the plant diversity and to utilize the biological resource sustainably, nature reserve management and programming should be strengthened.

This paper evaluated the aesthetic quality of forest scenery in Kanas tourism district by using scenic beauty estimation method（SBE）,and studied its relationship with natural fire disturbance. The results indicated: 1）The scenic beauty value of forest scenery was universally high, and people preferred the forest scenery with rich tree species and orderly storey. 2）There was a close relationship between forest scenery aesthetic quality and the time occurring natural fire disturbance. The earlier natural fire disturbance occurred the lower aesthetic value forest scenery was, vice versa. Fire disturbance was one of the main factors which influenced the forest scenery aesthetic quality by controlling formation of tree structure. This knowledge would provide reliable theoretic guidance and feasible scientific approaches for sustainable management of forest landscape and protection of biological diversity in terms of scenery aesthetic quality.

Lianas (woody vines) and the host trees were investigated in ten 20 m×50 m sample plots which were set respectively in valleys and hillslopes in the moist evergreen broadleaved forest in the Ailao mountains, SW China. In total, we recorded 402 climbing lianas DBH ≥1 cm, representing 23 species in 21 genera and 16 families, and 1 522 host trees DBH ≥10 cm, belonging to 47 species in 30 genera and 15 families. Compared to other subtropical forests, the lianas in the studied forest were rich in species, but low in abundance. The species richness, abundance and basal area of lianas were significantly higher in valley than in hillslope sites, whereas hosttrees did not differ significantly between the two sites. Lianas had a clumped distribution on trees, and there was a significant difference in the percentage of liana climbing among different host tree species (P ＜ 0.001), suggesting that lianas have some host selectivity. Those trees with smooth bark, such as Vaccinium duclouxii, Rhododendron leptothrium and Ilex gintungensis, were less likely to host lianas, while some trees with rough or slightly rough bark, such as Castanopsis wattii, Acer heptalobum, Symplocos sumuntia and S. ramosissima, were more likely to carry lianas than other tree species. The ratio of trees with lianas was higher in large sizeclass trees than in small sizeclasses. There were significant correlations between the DBH of stem twiners, hook climbers and the DBH of host trees (P ＜ 0.001), while there were no significant correlations between the DBH of root, tendril climbers and host trees (P ＞ 0.05).

Patterns of species diversity along the altitude on the northern slope of Xiaodonggou in the Altai mountains were explored. The results indicated that: the vegetation structure and composition were generally simple, and the diversity was low. Diversity order of the following three life forms was: trees < shrubs < herbaceous plants. Diversities of trees and shrubs exhibited a unimodal pattern with increasing altitude, peaking at the range of 1 600 m-1 800 m. The herbaceous plant diversity exhibited a monotonically increasing trend with the increase of altitude. Change in total diversity of the three life forms along the altitudinal gradient showed a unimodal pattern. Mixed coniferous broadleaved forest (1 600 m -1 700 m) had higher species diversity, where peak values for trees, shrubs, and total species diversity appeared. In the study area, tree crown density decreased along the altitudinal gradient, so that the diversity of herbaceous plants had an increasing trend along the altitudinal gradient accordingly.

In this paper, different expressions of a genetic model were presented for the halfsib progeny test of forest trees at a single site. Formulas of estimating the variance components were derived by using ANOVA method for both balanced data and unbalanced data based on the genetic model, and the procedures were also given for calculating sampling variances of the estimators and the statistic for hypothesis test of variance components. Furthermore, a formula of family heritability was given for unbalanced data, and the procedures to calculate sampling variances of family heritability and single tree heritability were also described. For any two quantitative traits, the methods to calculate the genetic correlation coefficient and its sampling variance were presented. Finally, a Windows software was developed to calculate all the parameters of the genetic model and can be freely used by forest breeders.

This paper reported that speciesspecific SSR markers were used to identify Liriodendron tulipifera, L. chinense and hybrid Liriodendron. Overall, 90 genotypes were taken as DNA amplification templates, of which 30 came from 20 provenances of L. chinense, 30 from 5 provenances of L. tulipifera, and 30 from 30 mating combinations of hybrid Liriodendron. Upon two round amplifying and screening, one speciesspecific pair primers for Liriodendron were screened from 176 pair primers. With the pair primers, a 190 bp fragment from L. chinense, 180 bp fragment from L. tulipifera, and a 190 bp and a 180 bp fragment from hybrid Liriodendron were respectively amplified. To testify the veracity of these pair primers, 10 individuals from L. chinense, 5 from L. tulipifera, and 10 from hybrid Liriodendron were used as amplification templates, and the results showed 100% veracity for species identification. Therefore, the development of the pair primers provided an effective, stable and reliable method for speciesspecific identification in Liriodendron at the molecular level.

A Granier TDP method was applied to continuously monitor sap flow of Schima superba which is native tree species in South China and data of the changes of environmental factors was synchronously collected to explore dynamic characteristic of trunk sap flux density at different temporal scales and its relation with different dominance and environment factors. The results showed that the daily pattern of sap flux density of dominant, middle and depressed woods exhibited a singlepeak curve. The maximum sap flux density of middle wood was slightly higher than that of dominant wood, but the depressed wood was far below those of middle and dominant. Photosynthetically active radiation (PAR) was major factor influencing trunk sap flux density of dominant and middle woods, while air temperature (TA) influenced mainly the depressed wood under the drought stress. Soil moisture (SM) did not apparently influence instantaneous sap flux density, but daily accumulated amount of flux in dominant woods.

Sorption and desorption characteristics of two phenolic acids, phydroxybenzoic acid and benzoic acid, in the rhizosphere soil of continuous cropping poplar plantations were investigated in order to find accumulation mechanism of the phenolic acids. An isotherms adsorption and desorption method and HPLC test were used. The results showed that rhizosphere soil of poplar plantation had strong adsorptive capacity to phydroxybenzoic acid and benzoic acid. The average adsorption rate of benzoic acid in the rhizosphere soil acid was from 39.53% to 47.46%, which was lower than that of phydroxybenzoic acid with an average adsorption rate from 63.39% to 72.26%. Fruendlich isotherms adsorption equation well described the adsorption process of those two phenolic acids in poplar rhizosphere soil, and there existed a significant linear relation between C_e (adsorption equilibrium concentration) and C_s (absorbance). The adsorption of those two phenolic acids belonged to physical adsorption. But, phydroxybenzoic acid had a stronger desorption capacity in different poplar plantation rhizosphere soil and the average desorption rate was from 46.62% to 52.89%. In comparison, the desorption rate of benzoic acid was lower, especially in balanced adsorption solution at high concentration. This rule was in accordance with the adsorption constant in the rhizosphere soil of different poplar generation. The sorption and desorption of those two phenolic acids reflected the property of environmental behavior in rhizosphere soil and could interpret accumulation of the phenolic acids in poplar rhizosphere soil.

Effects of cadmium chloride (CdCl₂) on morphology and architecture of roots and the content of malondialdehyde (MDA) in roots were studied using seedlings of Malus hupehensis var. pingyiensis grown in solution culture system. The results showed that 10-20 mg·L^-1CdCl₂ significantly decreased the fractal dimension (FD) of roots, taproot length, and root diameter in 5 days after treatment. The FD, the length of lateral roots, the surface area, volume and diameter of roots all decreased in 15 day treatment with 2.5-20 mg·L^-1 CdCl₂. The growth of lateral roots was more susceptible to CdCl₂ than taproots. CdCl₂ of 2.5-20 mg·L^-1 increased the proportion of thick root and altered the composition of roots significantly. The change of root composition was more significant with the increasing of CdCl₂ concentration. MDA content in roots increased significantly with 2.5-20 mg·L^-1 CdCl₂ treatment At the same concentration of CdCl₂, the change degree of root architecture parameters was higher than that MDA content in roots. The alteration of root architecture and morphology was derived from cell damage caused by CdCl₂.

Three twoyearold woody saltbushes (Atriplex gardneri, A. tridentata, A. canescens) and Hippophae rhamnoides were used to study effects of drought stress on physiological characteristics of woody saltbush. Three levels of soil moisture were used as the following: control (CK), moderate water stress (T₁), and severe water stress (T₂), and the soil moisture was controlled by weighing the pots. The results showed that: 1) the water holding capacity of three kinds of woody saltbush was far higher than H. rhamnoides, because of maintenance high bound water content; 2) under drought stress conditions, the cell membrane oxidation of A. gardneri and A. tridentata was low. MDA, resulted from cell membrane oxidation, of A. canescens under T₂ treatment was increased 19.3% than that of CK. The membrane permeability of three saltbushed did not significantly increased, suggesting good cell membrane structure and function. Under T₁ and T₂ drought level, a significant variation for MDA content of H. rhamnoides was found, increased 20.68% and 24.34% respectively in comparison with the control. There was severe cell membranes oxidation, which caused permeability of cell increased 37.38% and 41.58% respectively. 3) drought stress had no obviously impact on the synthesis of photosynthetic pigment of saltbushes. Under T2 treatment the Chl a and Chl b of H. rhamnoides was decreased 27.76% (P<0.05) and 44.18% (P<0.05) respectively. 4) according to the viewpoint of stomatal restriction value presented by Farquhar, under moderate drought stress, the decrease of P_n was caused by closure of stomata except A. tridentata whose low P_n was caused by nonstomatal factors. 5) Subordinate function value was used to evaluate the drought tolerant ability for the four species. The order was: H. rhamnoides>A. tridentata>A. gardneri>A. canescens.

In order to explore bioantisepsispreservation agents of fruits, inhibition effect of Bacillus subtilis to rot pathogen of blood orange and bioantisepsispreservation of B. subtilis preparation were investigated. Three effective bacteriostatic compositions were found in B. subtilis through the paper chromatography and the gel filtration chromatography. Two of them were big molecular weight substance with small quantity, while the orther was small molecular weight with a great amount. They had different bacteriostasis to the fungus of blood orange fruit. Alternaria spp. was sensitive to all the three components, while Penicillium spp. was sensitive to component Ⅱ and Ⅲ, which suggested that the antibiotic effect of the broadspectrum antagonistic microorganism had some selectivity. Biopreservation experimentation showed that the higher concentration of B. subtilis powder had better antiseptic effect, and protected fruits from dehydration. When the powder was diluted 20-100 times, the relative control effect decreased from 15.2% to 7.4%. Generally, the effect was better with 1-10 times dilution. Heating treatment could decrease the antiseptic effect of the components by 33.6%, however, the effect would increase 28.2% when aspirin was mixed with B. subtilisagents. Treatment time with the bioagents also had influence on the antiseptic effect. Within eight hours, the longer treatment time the better control effect. Generally treatment for 4-8 hours was the best. If biopowder combined preservation technique the control effect would enhance further. Rate of fruit weight loss would decrease and the edibility would increase, and the control effect would be comparable to 2,4-D, sportak and guoguang.

In nature, the effects of foraging experience on Kerria yunnanensis offspring population were studied. With the same foraging experience, the offspring of K. yunnanensis had different population density on different host tree species. The realized sex ratio of offspring had significant difference between Ficus glomerata var. chittagonga and Dalbergia obtusifolia, but no significant difference between other host trees. The offspring population mortality had no difference (P＞0.05) between Ficus glomerata var. chittagonga and Dalbergia balansae, whereas it had significant difference (P＜0.05) between other host trees. There was extremely signifcant difference (P＜0.01) in oviposition of offspring female between Ficus glomerata var. chittagonga and Dalbergia balansae, between Ficus cunia and Dalbergia balansae, but there was no difference (P＞0.05) between Ficus glomerata var. chittagonga and Ficus cunia. R₀ had certain difference among all host trees. With different experience, the offspring of K. yunnanensis had the same population density on the same host tree species, had different realized sex ratio, population mortality and oviposition (P＜0.05). After one life cycle on Dalbergia balansae and Ficus cunia, the R₀ on Ficus cunia had no difference (P＞0.05), after one life cycle on Dalbergia balansae and Ficus glomerata var. chittagonga, the R₀ on Ficus glomerata var. chittagonga had extremely significant difference (P＜0.01).

By using the emission factor(EF) method,this paper estimated the gases released from shrubs, herbages and litters layer between different forest type in Daxin’an Mountains during forest fires from 1980 to 2005The result showed that the amounts of CO₂, CO, C_xH_y, NO and SO₂ released from shrubs, herbages and litters layer were 25.04×10⁶, 5.72×10⁶, 0.21×10⁶, 0.09×10⁶ and 0.24×10⁶ t respectively. Betula platyphyllaLarix gmelinii, Betula platyphylla Rhododendron simsii and Quercus mongolica Lespediza bicolor were the main forest type for releasing the gases, accounting for more than seventy percent of total release. Additionally, the amount of SO₂ and NO released from Daxin’an Mountains would make up fifty percent of biomass fuels in China, it was almost the same quantity as the crop residues that are extensively concerned in agriculture field.

In this paper, we studied the forest fuel and potential fire behavior in terms of average maximal wind speed derived from records in Weijiacun Forest Center from 2000 to 2006. The fuel types were classified into coniferous forest, broadleaf forest, mixed forest, and sparse forest based on forest inventory and sample plots. Vertical and horizontal distribution of the fuel was calculated from sample plots and tree biomass model, including fuel loading, thickness and height. Based on fuel distribution and wind simulation, fire spread rate, fire intensity, and flame height of surface fire and crown fire were calculated. The fuel loading was 81.93,57.46,107.02 and 51.92 t·hm^-2 ,and crown base height was 230.0, 200.0, 200.0, and 280.0 cm respectively in coniferous forest, broadleaf forest, mixed forest, and sparse forest. Surface fire spread rate was 0.1～0.22 m·s^-1, and crown fire spread rate was 012～2.25 m·s^-1. Surface fire line intensity was 144～6 595 kW·m^-1, and crown fireline intensity was 3 214～189 002 kW·m^-1. Flame height of surface fire was 0.37～2.50 m, and flame height of crown fire was 1.75～13.4 m. All above quantitative data were crucial in fuel management and fire safety issues.

The wood anatomy of 43 collections, from East Asia, of 5 species within Sect. Illicium (Illiciaceae, Illicium Linn.) and 13 species, one subspecies of Sect. Cymbostemon (Spach.) A.C. Smith (Illiciaceae, Illicium Linn.) is investigated by light microscopy and scanning electron microscopy. The wood is diffused porous. Vessel elements are long, narrow, thinwalled, and angular; ends highly oblique; perforation plates are scalariform with many bars; vesselray pitting is scalariform. Rays are heterogeneous II, and uniseriate with procumbent cells. Axial parenchyma is sparse, diffuse arrangement. Most of species in Illiciaceae have above these ancestral features which support the family is one of the most primitively woody groups with vessels in extant dicotyledon. The comparison of the wood anatomic characters between Sect. Illicium and Cymbostemon shows marked quantitive differences. Furthermore, many features are shared in both Illiciaceae and Schisandraceae which suggests that the two families are closely related and it seem reasonable to set up Illiciales including Illiciaceae and Schisandraceae. At the same time, some differences in wood of the two families exist, which support the construction of Illiciaceae only including Illicium and also indicate Illiciaceae may be more primitive than Schisandraceae. Moreover, the vulnerability of Sect. Cymbostemon is found higher than that of Sect. Illicium, which theoretically shows that Sect. Cymbostemon distributed higher altitude and latitude, may suffer more intensity of drought and frost than Sect. Illicium, and the difference of vulnerability also support the division of Illicium into two sections in East Asia.

The effect of urea addition number and interval on the performance of urea-formaldehyde resins and the properties of plywood were studied by response surface methodology for the first time. The main chemical groups were qualitative analyzed using FTIR for exploring the effect of urea addition number and interval on these groups. The results showed that the solid content and curing time of UF (urea-formaldehyde) resins can not be notably affected by the number of additions and the interval of urea. and the viscosity, hydromethyl content, free formaldehyde content of the UF resins and properties of plywood were prominently affected by the number of additions and the interval between additions of urea. The main chemical groups of UF resins were influenced by the number of additions and the interval of urea. When the number of additions were two and the interval of urea was 20 min, the performance of UF resins and the properties of plywood were better.

In this paper， the waste plastic mixture was simulated by mechanically mixing polypropylene (PP) and polyethylene (PE)， the PP/PE mixture was blended and at the same time grafted with maleic anhydride (MAH) by reactive extruding， and the wood plastic composites was prepared with the grafted blend， which was used as matrix， and wood fiber. By comparing the infrared spectrogram of the grafted PP/PE blend with that of the unmodified blend， it proved that MAH was grafted onto PP/PE blend. Mechanical testing results showed that the flexural strength and unnotched impact strength of the composites were both significantly enhanced by the blendinggrafting modification of plastic mixture. When MAH dosage was 1%， the flexural strength increased 50.4% and the un-notched impact strength increased 90.8%， and the flexural strength and the un-notched impact strength of the composite prepared from waste plastic increased 40.2% and 53.4% respectively. The micromorphological analysis indicated that with modification the compatibility of PP and PE in the blend system was improved and the interfacial adhesion between wood fiber and PP/PE blend was also enhanced， thus it exhibited the elevation of the mechanical property. This blendinggrafting modification method can be considered as a feasible approach to expand the use of mixing waste plastics in the manufacture of high performance wood plastic composites.

The velocities of the chip flow could be as high as 60 m·s^－1 during MDF milling process, which made chip flow boundary and diffusion angle very difficult to be estimated. Meanwhile, the efficiency of dust absorbing could also be directly affected by characteristics of chip flow. In this research, clear images of chip flow were taken by CCD cameras from MDF milling process. The thresholds of these images were computed by applying Otsu's method. Based on those calculated thresholds, the images obtained from CCD cameras were converted to the binary images. Principle of eightconnectivity was adopted to collect the coordinates of chip flow boundary pixels. The boundary lines of the chip flow in the images could be detected and further traced by linking suitable boundary pixels based on their coordinates. Furthermore, diffusion angles of chip flow were determined when the least square method was applied. The experimental results showed that the diffusion angle of the chip flow dramatically increased when milling velocity was higher than 60 m·s^-1. Therefore, image processing method presented in this paper could provide the insightful understandings of characteristics of chip flow. Also this study could help further researches on both of highefficiency dust removal systems and dust collection hood design.

The concept of forest spatial structure，the forest spatial structure indices and the existing problems are introduced and discussed Then, current status and trend of forest spatial structure study is particularly described. This paper especially points out that many current studies mainly focus on diagnosis，description and simulation of forest spatial structure，and few study results are applied in forest management activities. Regulation and control of forest spatial structure facing to realistic forest management activities will be the study trend.

Terpenoid is an important secondary metabolites of plant, and it is involved in host recognition, information communication, and tritrophic system relation. Terpene synthases is one of most important regulatory enzymes in biosynthetic pathway of terpenoids, specially in regulation of terpene biodiversity. In conifers, studying terpene synthases deeply could make us use terpenoids to defend deseases and insect pests well. This paper focus on physical and chemical properties, gene and amino acid sequence characteristics, and regulation of conifer terpene synthases in recent years so that benefit research work in China.

Six plots were investigated and field data were obtained with the contiguous grid quadrate method in a natural Populus euphratica forest in the upper reaches of the Tarim river. We developed a static life table and a survival function of Populus pruinosa population based on the population life table and a theory of survival analysis. Survivorship curves，and the mortality rate were determined，and population dynamics were analyzed by using the spectral analysis. The results showed that： 1)Survival numbers of P.pruinosa populations were decreased with the increasing of age, and the expecting life of individuals with DBH larger than 40 cm declined obviously. 2)The Survivorship curve of the populations was Deevey Ⅲ. Four survival functions showed that the P.pruinosa population declined in young age and stabilized in old age. 3)There were two peaks of mortality rate existed in the lifespan：respectively occarred at the first and 11th age class periods. Seedling shortage was the restricting factor of development. 4) The spectral analysis of the populations showed that there was a marked periodic fluctuation in the process of natural regeneration. 5)The higher mortality rate of P. pruinosa seedlings might be integrated by the interplay of biological characteristics of P.pruinosa and deteriorating habitat（groundwater level decreasing）.

The variation of soil enzyme activities under a Karst forest was studied by comparing soil enzyme activity and soil nutrient content under different vegetation types and different ages of Zanthoxylum planispinum var. dingtanensis forest in Beipan River Karst gorge district. The Z. planispinum var. dingtanensis forest was the phase of the forest succession. The results indicated that, with increase of degradation intensity, the soil enzyme activity declined. The soil enzyme activity was in an order of forest>shrubbery(Z. planispinum var. dingtanensis forest)>bush>grassland. The soil enzyme activity declined obviously in the process of degradation. The soil enzyme activity of sucrase, amylase, proteinase, urease, phosphates, polyphen oxidase in the forest was higher than bush and grassland's. The Z. planispinum var. dingtanensis forest was on the mid of this process. Fertilization was able to stave off the soil's degeneration in short time. However the long-term effect of fertilization needs to be inspected.

An R2R3 MYB gene, PeMYBL1, was isolated from male inflorescence of Populus×euramericana by homologous cloning combined with in silico cloning techniques. The full length of PeMYBL1 cDNA was 1 094 bp encoding 276 amino acids. The deduced amino acid sequence contained two conserved MYB domains near the Nterminus, a conserved E1 motif and an acidic Ser/Thr rich region toward its C terminus. Phylogenetic analysis revealed that PeMYBL1 was clustered with AtMYB85 from Arabidopsis thaliana, ZmMYBL1 from Zea mays, OsMYB15 from Oryza sativa and ODORANT1 from Petunia hybrida. Furthermore, expression analysis by RTPCR showed that PeMYBL1 was expressed in root, stem, leaf, male and female infloresences, and abundantly accumulated in male inflorescences. The expression level of PeMYBL1 increased with the development of male inflorescences, indicating that PeMYBL1 is closely related to male flower development.

By using PCRbased molecular method，four new pear SFBB^-γ genes were isolated from 8 pear cultivars known as Sgenotypes. Length of PCR products from eight pear cultivars was around 1 200 bp. Sequencing the specific PCR fragments revealed four new SFBB^-γ genes that were respectively named as SFBB^16-γ（EU422956）, SFBB^-17-γ（EU422957）, SFBB²⁸-γ（EU422960）and SFBB^35-γ（EU422958）. As for different SFBB^-γ genes, variation in amino acid was higher in Fbox region and variable region 1, and lower in variable region 2 to 4 Phylogenetic analysis showed that there was a high level of difference between Japanese pear（Pyrus pyrifolia） SFBB^-γ genes and Xinjiang pear（P. sinkiangensis/i>） SFBB^-γ genes, as well as Japanese pear SFBB^-γ genes and Chinese white pear（P. bretschneideri） SFBB^γ genes. The results might reflect their genetic relationships among the species.

The increasingly mature nonlinear technique can facilitate accurate forecasting of transient sap flow process of plant. In this paper，the dominated tree species，Pinus tabulaeformis and Platycladus orientalis. in Beijing mountainous area were chosen for study. Their monitoring data range from June 18^th to September 9^th 2007 was derived to form the 1 985 sets of sample respectively. BP (back propagation) neural network models were established according to the theory of automaton network of discrete dynamic system，the target output of which was sap flow velocity and the inputs of which consisted of five influencing factors，ie，air temperature，relative humidity，light intensity，stem diameter growth and soil water potential. To improve the generalization quality of networks，Bayesian regularization and early stopping modes were involved in the training process. After training in two modes above，the linear regression between simulated outputs and the corresponding targets of test sample sets showed good fits (R>0.85)，which indicated a high forecasting precision of the models established，specifically when 11 neurons in hidden layer. Models demonstrated fine generalization under the two training modes in that the fit of test sample was equivalent to that of training sample，which further indicated their availability in practice.

The reproductive biology of Xanthoceras sorbifolia, an energy crop, was investigated through field observation, artifical pollination, anatomical techniques and fluorescence microscopy. Inflorescence buds of X. sorbifolia emerge at the beginning of March and flowers bloom in the following two months in Beijing, China. Flowering of individual trees lasts 25 to 30 days with the peak in the mid and late April. The inflorescence belongs to raceme with 20 to 50 flowers, which develop acropetally. The breeding system of X. sorbifolia is andromonoecious, i.e., hermaphroditic and male flowers appear on the same individual. Most inflorescences bear entirely male flowers, and a few inflorescences develop varying proportions of male and hermaphroditic flowers. Occasionally male flowers frequency is zero. Male flowers have obviously reduced nonfunctional pistils and are incapable of setting fruit. The pistils of male flower bear ovules prior to abortion. Dehiscence of five anthers in male flowers is asynchronous and anthers of only a few hermaphroditic flowers dehisce to shed pollens at anthesis. Although the pollen grains of both male and hermaphroditic flowers are viable, germination frequency of pollen of the hermaphroditic flowers on stigmas is extremely low. The most commonly observed visiting insects in this study area include honeybees, coccinellids and flies. Stigmas of the hermaphroditic flowers are receptive to self and crosspollens during the first 3 days of anthesis. Mature fruits merely come from crossfertilization while the development of selfpollinated ovaries is arrested soon after initially expanded growth. A freenuclear endosperm occurs in selffertilized ovules before abortion. Twocelled proembryoes were occasionally observed in the selffertilized ovules, but their development did not proceed and they degenerated after several days. This study revealed the trait of selfsterility in X. sorbifolia for the first time.

Crotalaria witches’-broom phytoplasma (CrWB) collected from Hainan Province, was classified and identified by sequencing techniques and Virtual RFLP. Two different type universal primer pairs of phytoplasma were used to amplify a 1.8 kb fragment of 16S rDNA and a 1.3 kb fragment of rp gene. The PCRamplified products were cloned and sequenced. The results of sequencing and homologuous comparison with other phytoplasmas showed that Crotalaria witches’-broom phytoplasma shared 99.9 % similarity with peanut witches’broom phytoplasma in 16S rRNA gene and 99.9% in rp gene. Crotalaria witches'-broom phytoplasma is sorted into Peanut witches'-broom group(16SrII), 16SrIIA, according to the results of Virtual RFLP of 16S rDNA, phylogenetic analysis of 16S rRNA and rp gene, which is related to Ca. Phytoplasma australasiae.

A total of 12 strains of Metarhizium anisopliae Sorokin were tested for pathogenicity to Hylobitelus xiaoi，and a superior strain was used to infect trials in a forest. The results indicated that the strain Ma1291-2 had strong pathogenicity to H.xiaoi after treatment for 30 d by dipping inoculation with (1.5±0.5)×10⁸ conidia·mL^-1. The correct mortality, the muscardine cadaver rate and the conidia content individual of H.xiaoi were respectively 70.59%, 70.81% and （1.90±0.34）×10⁸dia individual, and the quickest median lethal times (LT₅₀) were 13.89 d. The median lethal concentration (LC₅₀) was 1.135 3×10⁶ conidia·mL^-1. By infecting trials to H.xiaoi in a forest with the strain Ma1291-2, mortality of the treatment was extremely significant higher than the control, the correct mortality, the muscardine cadaver rate and the conidia content individual of H.xiaoi were 57.85%±1.19%, 55.43%±2.90% and (1.12±0.41)×10.8 conidia individual after 30 d, respectively, and the median lethal times (LT₅₀) was 16.56 d. The results suggest that the strain of Ma1291-2 has great application value.