Abstract:Soil water holding capacity of plantations established on severely eroded lands was studied in tropical region of South China. Four plantations representing a chronic series of restoration, including barren land, Eucalyptus forest, mixed broad-leaved plantation and secondary natural forest, were compared. Soil bulk density, water holding capacity and soil porosity were determined. The results showed that barren land with little vegetation cover had high soil bulk density (>1.5 g cm-3), and Eucalyptus plantation established on barren land made soil hardened and the water holding capacity became worse partly because of litter removal by villagers. Replacement of Eucalyptus plantation with mixed broad-leaved plantation markedly increased the water holding capacity of soil. Soil bulk density (0~40 cm) of the mixed broad-leavedf plantation was below 1.3 g cm-3 , and the total porosity was 46.1%～51.4%,and their non-capillary porosity were 15.0%～22.7%. The maximum water storage of the soil (0～40 cm) was 1892 t hm-2, a level similar to those of many other broad-leaved forests. The secondary natural forest located nearby had a better water-holding capacity than the mixed broad-leaved plantation. The surface soil bulk density was only 1.07 g cm-3, and the total porosity was 58%, and the maximum water-holding capacity was 538 g kg-1. Compared to those in 1983, mixed broad-leaved plantations largely improved soil physical properties with lowered soil bulk density and enhanced water-holding capacity. However, soils of barren land and Eucalyptus plantation had changed little, with hard surface soil and low water holding capacity. The results indicated that establishment of highly diversified plantation could enhance water infiltration and water holding capacity of soil.

Abstract:The growth, biomass and calorific values of 2-year-old Eucalyptus hybrid clone DH201 (Eucalyptus grandis  E. tereticornis) as an energy forest in Leizhou Peninsula were studied under different densities. The results showed that the effects of density on diameter at breast height (DBH) and height (HT) were significant, and which stand volumes were different at different development stages. The individual biomass was decreased with increment of density. The stand volume and biomass in 1-year-old were biggest at density of 10000 ind. hm-2 for 52.57 m3 hm-2 and 32.02 t hm-2, respectively, and which those in 2-year-old were biggest at 2500 ind. hm-2 for 75.85 m3 hm-2 and 45.66 t hm-2, respectively. The effects of densities on wood calorific values and ash contents were not different significantly. It suggested that the optimal densities for bio-engery plantations at 1- and 2-year-old were 10000 and 2500 ind. hm-2, respectively.

Abstract:The community structure and water holding capacity of litter and soil of Eucalyptus urophylta×E. eamalducensis plantations under different management densities in Yong’an City were studied. The results showed that the management density obviously affected the plantation structure, which had significant correlations to DHB and tree height, with correlation coefficient of -0.99 and -0.93, respectively, and that to stand volume with r=0.84．The effects of densities on species diversities from shrub layer to herb layer were different, which had significant correlation to shrub layer with r=0.94, and poor correlation to herb layer with r=-0.52. The species composition of undergrowth layer were great different under 5 different densities, and the vegetation yield under low density was the biggest．The litter maximum water holding capacity had significant correlation to stand densities with r=0.94．

Abstract:A field experiment was conducted in Acacia auriculaeformis plantation at the Heshan Hilly Land Interdisciplinary Experimental Station to investigate the short-term effects of earthworm (Ocnerodrilus occidentalis) and plant (Evodia lepta) on soil N2O and CH4 fluxes. The N2O and CH4 fluxes were measured in situ using the static chamber technique and analyzed with gas chromatogram for 15 days. The results showed that E. lepta did not significantly enhance soil N2O and CH4 fluxes, but fake plant (to simulate the physical effects of E. lepta) significantly increased soil N2O emissions (P<0.05). Earthworm promoted soil N2O fluxes in both control (without plant or fake plant) and the treatment with E. lepta by 26.7% and 66.3%, respectively. Contrary to our hypothesis, the effects of additional earthworm on soil N2O fluxes were not always positive. In the treatment with fake plant, the earthworm effects decreased the N2O fluxes by 39.7%. Meanwhile, the earthworm increased the CH4 uptake by 10.3% in control, but decreased the CH4 uptake by 90.6% in the treatment with fake plant and decreased CH4 uptake by 301.8% in the treatment with E. lepta. Earthworm addition shifted the soil CH4 from uptake to emission in the treatment with E. lepta and significantly decreased soil CH4 uptake in the treatment with fake plant (P<0.05). The results indicated that earthworm could accelerate soil N2O emission and might even convert CH4 sinks into sources in the A. auriculaeformis plantation. The physical effect of E. lepta facilitated soil N2O emission, while the biological processes of E. lepta might suppress soil N2O efflux. No significant correlations between N2O as well as CH4 fluxes and hydrothermal factors were found in the present study. In order to reduce the soil greenhouse gas emission, it will be useful to consider both the independent and interactive effects of plant physical processes, plant biological processes and earthworm activity on the efflux and influx of soil greenhouse gases.

Abstract:Twenty phenotypic characters from 5 natural populations of Camellia tunghinensis Chang were investigated. The variations in most phenotypic characters among populations were larger than those within populations, in which the variations in 13 characters among populations, such as fruits weight and diameter, eg., were very significant (P＜0.01). The variance range of SMPF/FM was the biggest, and that of seed longitudinal diameter was the smallest. The differences in overall phenotype among populations were not significant. The variation coefficient of 5 populations was in order of SFSH1 (0.272)＞MJG (0.217)＞SFSH (0.207)＞SHL (0.190)＞DGL (0.170). The correlations between average height, plant diameter at basal and various phenotypes characters were not significant, but it existed among phenotypic characters.

Abstract:The floral biology of Acacia auriculiformis A. Cunn. ex Benth. was investigated in a seed orchard at Shadui Town, Jiangmen City, Guangdong Province with the flower morphology observed under light microscopy and scanning electron microscopy (SEM). A. auriculiformis flowered from August to December. Its spike inflorescence consisted of 114.9±11.9 flowers, bearing 124.1±16.5 anthers in each flower. Within each anther existed eight pollen sacs, and eight polyads were produced with 16 pollen grains in each. It thus accounted of 15885 grains per flower. The pistil contained an average of 14.4±1.8 ovules with a smooth, wet stigma and a solid style. Pollen to ovule ratio (P/O) was 1103.1. Anthesis normally began at night and the whole process of flowering could be divided into 5 stages. The phenomena that style emerged from flower bud before stamen and that stamen emerged firstly were all observed during anthesis at different trees, which was inferred that A. auriculiformis was homogamous. As observed under SEM, anther began to dehisce along dehiscent line at stage 2, and completely opened at stage 4. Abundant polyads were released between 9:00 and 12:00. The stigma exudate emerged apparently during the first half-day after anthesis and then decreased gradually. Stigmas started to wilt at 3~4 days after anthesis. The stigma receptivity lasted about 3 days and the peak of receptivity began after 10: 00 at the first day.

Abstract:The chromosome numbers of six species of Chinese Melastoma L. and Tibouchina Aubl. in Melastomataceae and karyotypes of four speices of Melastoma were investigated. The results showed that the four Chinese Melastoma species was found to be diploid with the chromosome number 2n=24. The chromosome number of Tibouchina urvillean and T. heteromall was 2n=36. The karyotype formulae were as follows: M. malabathricum 2n=10m(2SAT)+14sm; M. sanguineur 2n=10m+12sm+2st; M. dodecandrum 2n=12m+12sm; M. intermedium 2n=12m＋10sm+2st. The karyotype analysis showed that the chromosomes in Melastoma were short in length, ranging from 0.43 to 1.79 µm. The arm ratios of all the chromosomes were larger than 2. The karyotypes were of Stebbins’s 2B type. The karyotypes of Melastoma were reported for the first time.

Abstract:The chromosome numbers and karyotypes of two species of Halophila are reported. Somatic chromosome numbers of the two species all were 2n=18(x=9). Their karyotype formulas were as follows: 2n = 2x = 18 = 4m + 14sm for H. ovalis (R. Br.) Hook. f., and 2n = 2x = 18 = 8m + 10sm for H. beccarii Asch which is reported for the first time. The karyotypes of the two species belong to category 2B of Stebbins.

Abstract:Glochidion multiloculare (Rottler ex Willd.) Voigt and Glochidion moonii Thwaites, two species of Glochidion J. R. et G. Forst. (Euphorbiaceae) are newly recorded from China.

Abstract:Staurogyne diandra E. Hossain is transferred to the genus Ophiorrhiziphyllon Kurz. for its flowers with two fertile stamens; a new combination, Ophiorrhiziphyllon diandra (E. Hossain) H. J. Xin, D. V. Hai & Y. F. Deng, is proposed.

Abstract:Liparis sootenzanensis Fukuyama，previously only reported from Taiwan, was reported in mainland China for the first time. The species is characterized by its pseudobulb stout with large leaves. Its racemose inflorescence has 10-flowered. Flower is light green, with silk petals and obovate lip with serrulate edges at apex.Voucher specimens were preserved in Herbarium of Maolan Reserve (HML).

Abstract:Eria foetida Aver (Orchidaceae) was reported as a new record from China. Detailed description and colourful photos were provided.

Abstract:The genus Deinocheilos W. T. Wang（Gesneriaceae）and the species Deinocheilos jiangxiense W. T. Wang were reported as new records from Zhejiang Province, China. The voucher specimens are preserved in the herbarium of Zhejiang Forestry College (ZJFC)

Abstract:From March 2008 to April 2009, the morphological taxonomy of Microcystis collected from several typical scene lakes/ponds in Guangzhou was studied. Eleven Microcystis taxa had been identified totally as M. aeruginosa Kützing, M. botrys Teiling, M. firma Kützing, M. flosaquae Wittrock, M. ichthyoblabe Kützing, M. novacekii Komárek, M. pallida (Farlow) Lemm., M. pseudofilamentosa Crow, M. smithii Komárek & Anagnostidis, M. viridis A. Braun and M. wesenbergii Komárek. Their morphological characters were described and photoed under light microscope, and the morphological differences among Microcystis species were compared.

Abstract:Longan fruits of 19 varieties introduced to Guangzhou were compared and evaluated in the characteristics of fruit quality. The results showed that there were no significant differences in most of the apparent characteristics among the varieties except for the fruit shape and flesh texture, and there were also some correlations between some of the characteristics. There were significant negative correlations between fruit size and total soluble solids (TSS) content, as well as between skin thickness and TSS. The fruits with thin skin, thick pulp or with the shape of oblate spheroid in transverse were positively correlated to the high edible rate. The 19 varieties were classified into 3 clusters using a hierarchical clustering method and evaluated according to the 8 quality indices. By performing a factor analysis based on the principal component, the 8 quality indices were represented with 3 principal components (their cumulative contribution reached 88.27%). It was concluded that the simplified evaluation indices included mass per fruit, fruit shape index, edible and pulp thickness rate. Further more, the clustering results of 19 varieties according to the factor scores and the simplified indices were coincident with each other.

Abstract:Four emerged Macrophytes, Sagittaria trifolia, Echinodorus berteroi, Acorus calamus and Phragmites australis, were cultured with synthetic wastewater in phytotron hydroponic system. The eco-physiological characteristics, such as biomass, root length, root lifespan, root porosity, root radial oxygen loss (ROL), photosynthesis and decontamination efficiency of total nitrogen, total phosphorus and COD were compared. The results showed that ROL positive correlated to root porosity, photosynthetic rate and biomass (P<0.05), and significant to root length (P<0.01). The removal rate of TP and COD correlated to photosynthetic rate and ROL, respectively, while the removal rate of TN significantly positive correlated to biomass (P<0.01), and it is negative to root/shoot ratio. Compared with A. calamus and P. australis, S. trifolia and E. berteroi had large biomass, well-developed root system, relatively high physical index in root porosity, ROL and photosynthesis, and a closer or even better decontamination efficiency. It suggested that S. trifolia and E. berteroi might be excellent species for constructing wetlands.

Abstract:Alexandrium tamarense was a wide-spread species of dinoflagellate causing harmful algal blooms and paralytic shellfish poisoning around the world. The genetic diversity of 5 European and 4 Chinese strains of A. tamarense was analyzed by using microsatellite markers. Relative low genetic diversity was revealed in the 9 strains of A. tamarense, with effective number of alleles of 1.3243~3.2667 and gene diversity of 0.3630. Based on the markers, the 9 strains of A. tamarense were divided into three lineages with genetic differentiation of 0.7522, which related to their geographic origins. Chinese samples could be divided into two lineages, and the European strains belong to another lineage. High genetic differentiation among the three populations suggested the lack of gene flow.

Abstract:OsMATE, the closest homology of sorghum (Sorghum bicolor) SbMATE, was cloned by PCR technique from rice (Oryza sativa) leaves, and then its expression pattern was analysed in different tissues and under abiotic stresses by semi-quantitative RT-PCR. The result showed that OsMATE expressed lowly in rice roots and leaves, and almost none in leaf sheaths. OsMATE expressed strongly in rice roots induced by abiotic stresses, such as aluminum (Al), cadmium, arsenic, salt, iron, PEG6000, paraquat and ABA, while little expressed in leaves by arsenic, salt and PEG6000 stress. The expression of OsMATE in roots of the Al-resistant ‘XN1’ was more than that in the Al-susceptible ‘XX2’ under Al stress. It suggested that OsMATE could play an important role in stress resistance of rice under abiotic stresses.

Abstract:Four cardenolides were obtained from the latex of Antiaris toxicaria (Pers.) Lesch. On the basis of spectral data, they were identified as strophanthojavoside (1), convallatoxin (2), strophalloside (3), and glucostrophanthidin (4). Compound 4 was isolated from Antiaris toxicaria for the first time. Compounds 1~4 showed significant inhibitory activity towards chronic myelogenous leukemia (K562), human gastric carcinoma (SGC-7901), and human hepatoma (SMMC-7721) cell lines.

Abstract:Six compounds were isolated from mango (Mangifera indica L.) seed kernels. On the basis of spectral data and references, they were identified as gallic acid (1), methyl gallate (2), ethyl gallate (3), methyl m-digallate (4), p-hydroxybenzoic acid (5), and succinic acid monomethyl ester (6), which were obtained from mango seeds for the first time. Antimicrobial activity of compounds 1~5 against seven bacterial and four fungal strains was determined by using the agar plate dilution method. The results showed that the minimal inhibitory concentration (MIC) values of compound 1 against Staphylococcus aureus, S. epidermidis, Corynebacterium xerosis, and Micrococcus luteus were 50~100 µg mL-1, and compound 4 exhibited inhibitory activity against Pseudomonas aeruginosa.

Abstract:The effects of IBA and different cutting types, retaining leaves ways on cutting propagation of wild vegetable Solanum photeinocarpum cultured in water were studied. The results showed that the rooting from shoot with half leaf was 100% treated with 5～35 mg L-1 IBA, but the average of rooting was the highest treated with 20 mg L-1 IBA. The rooting from hardwoods with half leaf could be promoted treated with 15～35 mg L-1 IBA, which it had the best effect treated with 35 mg L-1 IBA. The softwoods and hardwoods treated with 20 and 25 mg L-1 IBA, respectively, the rooting effects was in order of segments with half leaf > whole leaf > without leaf.

Abstract:The changes in physiology and biochemistry of Citrus fruits and morphology of peel and pulp during juice sacs granulation were reviewed. The major factors and control measures of granulation of Citrus fruit were discussed.

Abstract:Hybridization of Paphiopedilum has been performed for more than 150 years and 20 262 hybrids had been registered in RHS until 1 July, 2009. The research progress and prospect of cross breeding of Paphiopedilum were reviewed, such as germplasm resources, hybrid registering, the method of cross breeding, the choice of hybridization parents, hybridization between Paphiopedilum and other genera, color heredity and the problem of cross breeding. The advice of breeding direction was also proposed according to the current situation of Paphiopedilum breeding in China.