Abstract:In order to understand soil respiration characteristics of tea garden from Red Soil Region in South China, soil respiration rate in a 3-year-old tea garden were investigated with LI-Cor8100 open soil carbon flux system from January to December in 2011. The seasonal variation and spatial heterogeneity of soil respiration rate were studied. The results showed that monthly dynamic changes of soil respiration rate in the tea garden correlated significantly with temperature (P<0.01). Soil temperature at 10 cm depth could explain 67.79%-88.52% of monthly dynamic changes of soil respiration at four observation areas in the tea garden. The Q₁₀ value of soil respiration derived from the exponential equation at different observation areas in tea garden ranged from 1.58 to 1.86. There was obvious spatial heterogeneity for soil respiration at tea line scale in tea garden, the soil respiration rate was higher close to tea tree base. The spatial variation of root biomass could explain 82.68% of spatial heterogeneity of soil respiration rate. So, the difference in spatial distribution of roots was main reason for spatial heterogeneity of soil respiration rate.

Abstract:In order to determine the vertical contents and the seasonal variations of none-labile carbon (NLC) under different forest types, soils samples at 0～10, 10～20 and 20～40 cm depth were collected from six forests, including shrub-grass forest, masson pine forest, Eucalyptus forest, native-species forest, Acacia forest and monsoon evergreen broad-leaved forest, respectively, in Heshan. The results showed that soil NLC declined with the soil depth in the six types of forest with the highest NLC contents at the surface layer (0～10 cm depth). At the surface layer soil, the contents of NLC were significantly different among the forest types with the highest level in Acacia forest and the lowest level in masson pine forest. At the deeper layers (10～20 cm and 20～40 cm depth), the Acacia forest had the highest NLC while the other 5 forest types had the contents of NLC without significant differences. Among the six forest types, there were seasonal patterns of soil NLC with the higher ratios of NLC to soil organic carbon (SOC) in wet season than in dry season. The ratios of NLC/SOC among the six forest types indicated that Acacia forest and shrub-grass forest were helpful to increase the contents of soil NLC at all layers,while masson pine forest, Eucalyptus forest, native-species forest, and monsoon evergreen broad-leaved forest were helpful to stabilize the contents of SOC at deeper soils.

Abstract:The purpose was to comprehend the dynamic changes in carbon and nitrogen storage of Phyllostachys edulis forest with rhizome expansion, the changes in carbon and nitrogen storage of P. edulis forest in Yong'an City, Fujian Province were studied with abandoned land and 14-year-old Chinese fir (Cunninghamia lanceolata) forest as control. The results showed that the carbon and nitrogen storage of forest was higher significantly than that of abandoned land. The carbon storage of P. edulis forest deceased firstly and then increased quickly when Chinese fir transformed into moso bamboo. The carbon storage reached the maximum when moso bamboo forest was 10 years old, and then decreased with age increasing. The change trend of carbon storage was difference from that of nitrogen storage. The nitrogen storage of moso bamboo forest with more than 10-year-old was higher significantly than that of 14-year-old Chinese fir, and the nitrogen storage of moso bamboo forest at the age of 5 were lower significantly than that of Chinese fir. The carbon and nitrogen storages of all forest types were in the order: soil layer > tree layer > litter-fall layer > vegetation layer under canopy. Meanwhile, the carbon and nitrogen storages in soil layer decreased while those in tree layer increased. The carbon and nitrogen storages in litter-fall of moso bamboo were higher than those in abandoned land, and lower than those in Chinese fir forest. Meanwhile, the carbon and nitrogen storages in litter-fall of moso bamboo forest decreased with stand age increasing. The low carbon and nitrogen storages in litter-fall of moso bamboo forest may decline continued carbon sequestration capacity. So, it was important to balance the carbon and nitrogen storages between tree layer and soil layer.

Abstract:Examination of specimens (including the types) has shown that Senecio daochengensis Y. L. Chen is conspecific with S. atrofuscus Grierson and thus is placed in synonymy under the latter. A distribution map and a key to S. atrofuscus and its related species are provided.

Abstract:Both herbarium and field observation have shown that Dalbergia peishaensis Chun et T. Chen is conspecific with D. tsoi Merr. et Chun. Therefore, D. peishaensis is reduced to synonym under D. tsoi herein.

Abstract:Three species of the genus Ardisia (Primulaceae) were reported as new records from Kachin State of Myanmar, such as Ardisia corymbifera Mez, Ardisia maculosa Mez and Ardisia interjacens C. M. Hu & J. E. Vidal.

Abstract:Oberonia falcata King & Pantl. and O. kanburiensis Seidenf. are new to Chinese flora. O. falcata is characterized by elongate stem, falcate leaves, reflexed sepals and the midlobes of lip bilobed, with acute angle and acute apexes. O. kanburiensis is marked with fringed petals and lip, which constrict at middle part then widen forward to the greatest width.

Abstract:The aim of this study was to find the relationship between megasporogenesis, development of female gametophyte and morphological changes of flower, ovule in Siraitia grosvenorii. The ovaries were observed under light microscope by means of paraffin wax fixation. The results showed that ovule of Siraitia grosvenorii was anatropous, bitegmic and crassinucellar. The chalazal megaspore of linear tetrad developed into Polygonumtype embryo sac. Morphological changes of flower and ovule indicated different developmental stages of megasporogenesis and female gametophyte. As the length of ovary ranged from 7 to 9 mm and the nucellus were oval-shape, 45.83% megaspore mother cells were at the stage of meiosis. These suggested that the morphological characteristics of flower and ovule could be used to distinguish different stages of megasporogenesis and female gametophyte development of Siraitia grosvenorii.

Abstract:Dendrobium huoshanense is a traditional precious and rare Chinese herbal medicine. In order to improve propagation and cultivation technique of seedlings, the way of artificial pollination, techniques of aseptic sowing and seedling transplanting were studied. The results showed that fruit setting rate of cross-pollination in greenhouse through artificial pollination exceeded 65%, while that of self-pollination was less than 4%, and the fruit development of cross-pollination is better than that of self-pollination. However, the time of fruit ripening was similar both cross-pollination and self-pollination. Under aseptic culture condition, the fruit setting rate of cross-pollination reached 18.18% through artificial pollination, and the fruit ripening time was shorter 67 days than that in greenhouse. The germination rate of seeds derived from cross-pollination and stored at 4℃ for 2.5 years could exceed 80%, which was higher 20% than that from self-pollination. The culture medium supplemented with juice of potato, banana and apple could promote seedling growth, and among them, banana juice was the best. The optimum transplant matrix was mixed with 3/10 bark in bottom and 7/10 sawdust on upper layer, the survival could reach 78% and the number of new buds was 2.7 per clump, which may relate to its good water retention and air permeability.

Abstract:In para rubber tree (Hevea brasiliensis), HbSUT3 plays the role of key sucrose transporter (SUT) in sucrose loading into laticifers and rubber productivity, whereas HbSUT5 is putatively involved in the regulation of sucrose loading into laticifers. To further investigate the functions of the two SUT genes, digoxigenin-labeled cRNA probes were prepared, and used by in situ hybridization to detect the distribution patterns of HbSUT3 and HbSUT5 mRNAs in tissues of rubber young stems and midribs. The results showed that the two SUT genes were mainly expressed in phloem and cortex of barks in young stems, whereas they were expressed in all tissues of midribs except for xylem. The expressions of HbSUT3 were similar between young stems and midribs, while the expression of HbSUT5 in young stems was much higher than that in midribs. It was suggested that HbSUT3 and HbSUT5 could involve in activities, such as phloem loading, sucrose transportation and supply to sink cells, and they also had functional differentiation.

Abstract:SCoT-PCR amplification system of macadamia (Macadamia spp.) was optimized and established by using single factor design, such as Mg²⁺, dNTPs, primer, Taq DNA polymerase and DNA template, and DNA fingerprint maps of macadamia germplasms were constructed. The results showed that final volume of optimum reaction system was 20 μL, including 2.5 mmol L^-1 Mg²⁺, 0.3 mmol L^-1 dNTPs, 0.8 μmolL^-1 primer, 1.0 U Taq DNA polymerase, 40 mgL^-1 template DNA, and 2 μL 10 × buffer with ddH₂O water. The suitable annealing temperature of primers was 50℃. The optimum SCoT-PCR system was shown to be steady and reliable. The 12 germplasms of macadamia could be absolutely identified by primer SC5 and SC34 + SC39 with 99.988% probability of confidence, every germplasm of macadamia had a unique fingerprint map. It showed that the optimum SCoT-PCR system could be applied effectively in germplasm identification and genetic diversity analysis of macadamia.

Abstract:In order to compare the phenolics in Salvia miltiorrhiza with different sources, the phenolics extracted from different sources were studied by chemical fingerprinting method, and salvianolic acid B as marker molecule was quantitatively analyzed. The results showed that the absolute amounts of phenolics in S. miltiorrhiza roots were seriously affected by different factors, such as origin, harvest time, root disease, root color, root diameter, and the part of plant. However, these factors had little influence on relative amounts of phenolics. The chemical fingerprinting of phenolics derived from different sources had high similarity. The content of salvianolic acid B harvested in August was the highest, and which was significantly reduced by diseases, such as root rot and nematode. Contents of phenolics in the brick red roots were the highest, compared to puce and white roots. The bigger the diameter, the higher contents of phenolics were. So, these could provide the basis for quality evaluation and resource utilization of S. miltiorrhiza.

Abstract:In order to understand the chemical constituents extracted from Myoporum bontioides A. Gray, eleven flavonoid compounds were isolated from the leaves of M. bontioides by chromatographic separation methods. On the basis of spectral data, they were identified as tangeretin (1), sinensetin (2), 5,4'-dihydroxy-6,7,8,3'-tetramethoxyflavone (3), 4',5,7,8-pentamethoxyflavone (4), 5-demethylnobiletin (5), 5-hydroxy- 6,7,3',4'-tetramethoxyflavone (6), nobiletin (7), dihydrokaempferol (8), luteolin (9), 3-methoxy-3',4',5,7- tetrahydroxyflavone (10), and apigenin (11). All these compounds were obtained from M. bontioides for the first time except compound 9. The compounds 1, 2, 8 and 9 had strong antifungal activity against Colletotrichum musae by using spore germination inhibition assay. So, these could provide a theoretical basis for utilizing the active ingredients in leaves of M. bontioides.

Abstract:In order to understand taxonomy position of Aquilarioideae, belonging to Thymelaeceae, the chemical constituents extracted from the genus Aquilaria was summarized, and the chemotaxonomy of subfamily Aquilarioideae was discussed by comparing the chemical constituents from other subfamilies in Thymelaeceae. It was regarded that the evolution status of subfamily Aquilarioideae was lower than that of subfamily Thymelaeoideae according to the types of diterpenoid and flavonoid, but higher than that of subfamily Gonystyloideae according to the type of triterpenoid. At the same time, 2-(2-phenylethyl) chromones and dibenzophenones were taken as the characteristic components of the genus Aquilaria, or even subfamily Aquilarioideae. Therefore, the status of subfamily Aquilarioideae was approved and regarded as the lower evolution group in Thymelaeceae, exiting between subfamily Thymelaeoideae and subfamily Gonystyloideae.

Abstract:Dendrobium, epiphyticly growing on tree or rock, is one of the largest genus in orchid family, belonging to Dendrobiinae of Epidendroideae. Most of species in this genus have high medicinal and ornamental values. Howerver, the wild species of Dendrobium has been threatened because of over-collection and habitat deterioration in recent years. Dendrobium is one of typical orchid mycorrhizal plants, it needs symbiosisn with mycorrhizal fungi to complete its life cycle under natural conditions. Mycorrhizal fungus have important roles in Dendrobium seed germination and plant growth. the conformation of Dendrobium mycorrhizae, effects and diversity of mycorrhizal fungi in Dendrobium were reviewed, as well as the mycorrhizal technology utilization in Dendrobium. In addition, some ideas based on the current researches are proposed for future studies.