Abstract:The spatial patterns and differentiation of species diversity of seed plants in Yunnan, China, were investigated based on distribution datasets of plant species at large scale, geographical information system and statistic methods. The results indicated that the discreteness of datasets of plant diversity and flora differentiation increased from families to genera and species. Compared with genera and species, the spatial variation and diversity centers of families were not obvious, which may be due to different historical periods in geology reflected by families, genera and species. The diversities of genera and species in southern Yunnan were richer than those of other areas except northwest Yunnan. The diversity centers of species were mainly observed in northwest Yunnnan, southern Yunnan, regions of Ailao Mountain, Wuliang Mountain, and Kunming region, which may be related to the geographical patterns of habitat heterogeneity and energy. Compared with families, the spatial variation of genera differentiation was more easily observed and showed similar patterns with species diversity, indicating significant correlation between plant diversity and flora differentiation. Compared with families, the centers of genera differentiation were obvious. On the whole, the spatial patterns of species diversity of seed plants and its differentiation were jointly shaped by habitat heterogeneity, energy and geological history.

Abstract:In order to understand water use characteristics of Schima superba plantation and their relationships with environmental factors, Granier’s thermal dissipation probes were applied to measure sap flow density of 15 trees in a typical plantation stand, in which environmental factors including photosynthetically active radiation (PAR), air relative humidity, air temperature and soil moisture were recorded synchronously. Stand transpiration (Jd) and canopy stomatal conductance (gs) were then calculated based on sap flow density, sapwood area, environmental humidity and temperature from December 2007 (dry season) and September 2008 (wet season). The results showed that trees with larger sapwood areas had greater contribution of stand transpiration. Jd was found to be significantly different during wet and dry seasons, which had an average of 21.1 g H2O s-1 in September but only 7.03 g H2O s-1 in December, indicating a dramatic seasonal variation of it. In the meantime, Jd was found to be significantly correlated with environmental factors, in which PAR had the largest correlation coefficient and followed by vapor pressure deficit (VPD), air relative humidity and air temperature in sequence. On the other hand, the maximum gs were calculated to be 30.8 mmol m-2s-1 and 19.7 mmol m-2s-1 in September and December, respectively. It had positive linear relationship with PAR but negative one with VPD when PAR was larger than 1000 μmol m-2s-1 and VPD was over 2 kPa. However, gs did not present any statistically significant relation with soil moisture either in July or December, indicating that soil moisture was not the major environmental factor influencing stand transpiration of S. superba during our study periods.

Abstract:The carbon stock and total organic carbon (TOC) stability in soils of four typical plantations at 25-year-old in South China were investigated. The TOC content, labile carbon pool and soil microbial carbon in soil depth of 0~10 cm and 10~20 cm were determined. The results showed that soil TOC contents were in order as Acacia mangium > Acacia auriculaeformis > Pinus ellettii > Schima superba forest. Legume plantations (A. mangium and A. auriculaeformis) had markedly higher TOC content than non-legumes plantations (P. ellettii and S. superba). The TOC contents in two soil layers of A. mangium plantation were twice as high as those of S. superba plantation. S. superba plantation had the highest labile carbon pool (7.80 mg g-1) and the shortest turnover time (49 d). On the contrast, A. mangium plantation had the lowest labile carbon pool (2.14 mg g-1) and Clab/TOC (8.63%). A. mangium plantation had more stable TOC than other 3 plantations. The microbial carbon contents in surface soil layer (0~10 cm) were in order as A. mangium plantation>P. ellettii plantation>A. auriculaeformis plantation>S. superba plantation. It suggested more microbes favored transformation of litter into soil organic matter. At the subsoil layer (10~20 cm), soil microbial carbon in A. auriculaeformis plantation was significantly higher than those in others forest types, though it was very low in this layer. A. mangium plantation had the lowest microbial carbon content. It suggested that soil TOC accumulation in plantations was closely related to stability of organic matter and quantity of soil microbes.

Abstract:The introduction experiments of 21 cold-tolerant species with 53 provenances of Eucalyptus at 5.5-year-old had been carried out, which survival and growth characteristics were studied. The results showed that there were significant differences among species and provenances in plant height, DBH and volume and survival. The tested species/provenances could be divided into five clusters by cluster analysis. The E. grandis, E. dunnii and E. benthamii, derived from Near Coffs Harbour NSW (20116) and NSW (20633 and 18788), respectively, had high volume growth at 5-year-old for 171.03 m3 hm-2, 158.61 m3 hm-2 and 110.962 m3 hm-2, respectively. The original altitude had little effect on growth and adaptability, whereas rainfall pattern was the key factor for introduction. The best species/provenances were introduced from 26º~30ºS including southern Queensland, New South Wares and northern Victoria of Austria. E. dunnii, E. grandis, E. benthamii and E. saligna could tolerant the low temperature of -4℃～-4.5℃, so that they were suitable for introduction in mountane region of western Fujian.

Abstract:The natural water moisture and effective water holding capacity of coarse woody debris (CWD) in three typical forest ecosystems in Tianbaoyan National Nature Reserve were studied. The results showed that the water holding capacity of CWD was lowest in the Crytomeria fortunei forest；the water holding capacity was in order as fallen tree＞snags＞stumps in Rhododendron simiarum forest, and snags＞fallen tree＞stumps in Tsuga longibracteata and Crytomeria fortunei forests. The effective water holding capacity of CWD increased with decay class of CWD increment，as well as the natural moisture content of CWD.

Abstract:The habitat and natural regeneration capacity of Dracaena cambodiana Pierre ex Gagnep in Hainan Island and the extent of human damage to its wild population were investigated and analyzed, and its endangered reasons were also discussed. The results showed that D.cambodiana was a typical rock-associated plant species and mainly distributed in the high-temperature and less-rainfall regions. D. cambodiana usually grew in the gap of steep and bare limestone or granite, or in sandy loam soil alongside the rock, and its associated species were often some small trees and shrubs. Due to the unrestricted exploitation of the wild plants and the destruction of its habitats, the wild resources of D. cambodiana have been very limited. In natural conditions, there were three ways for the regeneration of D. cambodiana, including the reproduction through seeds and the sprouts from roots and stumps. However, under the existing habitats, all of them were unable to effectively enlarge their wild population. It was concluded that the original habitat destruction and the unrestricted exploitation were the external factors for the endangerment of D. cambodiana, and the failure of seed germination or seedling growth under the poor habitats was the internal and major factor causing its endangerment, both of which made the species in an endangered status.

Abstract:The internal transcribed sequence of the nuclear ribosomal DNA (nrDNA-ITS) was chosen as the target sequence to resolve the phylogeny of the genus Viola in China. 66 sequences (39 of which were reported for the first time) of 55 ingroup taxa were collected, with Hybanthus concolor and Scyphellandra pierrei as outgroups. Molecular phylogenetic trees strongly supported the monophyly of Sect. Viola, Sect. Diffusae, Sect. Bilobatae and Sect. Vaginatae. The close sister relationship among Subgen. Melanium, Sect. Viola and Sect. Trigonocarpae was revealed, however, the clade of Sect. Trigonocarpae got low support. Subgen. Dischidium was confirmed to have a very close relationship with Subgen. Chamaemelanium by maximum parsimony tree, but the two Sections (Sect. Longicalcaratae and Sect. Brevicalcaratae) under Subgen. Dischidium should be combined together. Phylogenetic trees also showed that Pinnatae should be treated as a subsection under Sect. Adnatae. Besides, the systematic status of V. lucens, V. magnifica, V. dissecta and V. yunnanensis were discussed combining molecular results with morphologic characters.

Abstract:Minor venation patterns of Syndiclis, Beilschmiedia, Potameia, Sinopora, and Endiandra were observed. The results showed that their venation patterns could be grouped into three types, the Type A with fine leaf reticulations bearing no free ending of veinlets, the Type B with fine leaf reticulations having free and simple ending of veinlets, and the Type C with coarse leaf reticulations possessing profusely branched ending of veinlets. Beilschmiedia was provided with the most diversified venation including all 3 types while other genera had only one of the 3 types each. Syndiclis, Sinopora, and the Chinese Endiandra shared the Type A venation pattern which was different from Potameia with the Type C venation pattern.

Abstract:Pollinaria morphology of 17 species of Tylophora in China was observed under light microscope (LM). Four types of retinaculum (oblong, square, triangle and inverse triangle) and three types of pollinia (spheroidal, prolate and perprolate) were observed. The length of the caudicle, the shape and size of retinaculum and pollinia varied markedly. So these characters could be used to discriminate different species within Tylophora. Therefore, they were of significance in studying on classification of Tylophora.

Abstract:The distribution and development of mucilage cells of Anredera cordifolia (Tenore) Steenis were studied by using paraffin sectioning. The results showed that mucilage cells generally exist in stem, leaf and leaf stalk of A. cordifolia. They scattered single in the pith and cortex of stem, and existed in both palisade tissue and spongy tissue of leaf, which spongy tissue had more mucilage cells than palisade tissue. There was a few mucilage cells in leaf stalk distributed in cortexes around of vascular bundles. The development of mucilage cells could be divided into 4 stages, such as initial cell stage, vacuolation stage, mature stage, and disintegration stage. The mucilage cell originated in the sixth leaf primordium, and the development of mucilage cells are not synchronized to that of stem and leaf.

Abstract:Michelia mannii King (Magnoliaceae), a previously known species only in Bristish India, is newly recorded from Vietnam. It was found in primary limestone forest in Cuc Phuong National Park, Northern Vietnam and in Langbiang Plateau, Lam Dong Province, Southern Vietnam. The specimens of this species are being preserved in CHI, CPNP, IBSC, L, and VFU.

Abstract:A total of 48501 expressed sequence tags (ESTs) of Castanea mollissima were obtained from database of Fagaceae Genomics, of which 8479 ESTs contain 12116 simple sequence repeats (SSRs) with motifs longer than 10 bp, with the frequency of SSRs up to 24.98%. Dinucleotide and trinucleotide repeats are the main EST-SSR types in Chinese chestnut, accounting for 38.05% and 42.20% of all EST-SSRs, respectively. The Chinese chestnut EST-SSR markers showed 100% transferability across the two endemic species to China, C. henryi and C. seguinii. There were 106, 108 and 101 polymorphic loci from 115 loci in C. mollissima, C. seguinii and C. henryi, respectively. While 260 out of the 575 alleles (45.22%) were shared among the three species, unique alleles in each species were also detected. These informative EST-SSR markers can be used in population genetic studies and comparative mapping of Chinese chestnuts.

Abstract:ζ-carotene Desatura (ZDS) is one of the rate-limiting enzymes in the carotenoids biosynthetic pathway. The ZDS gene named as FaZDS was cloned from strawberry (Fragaria ananassa Duchesne) fruit using RT-PCR and RACE techniques. The results showed that the length of FaZDS cDNA was 2148 bp with an open reading frame of 1710 bp, which encoded a polypeptide of 569 amino acids. Homology analysis showed that the deduced ZDS protein was highly homologous to those from other species. Phylogenetic analysis also indicated that ZDS in strawberry was close to apple. Prokaryotic expression showed that recombinant FaZDS had highly expression in E. coli BL21. The FaZDS could express in flower, fruit and leaf by semi-quantitative RT-PCR analysis, with the order as flower > red fruit > pink fruit > white fruit > green fruit > leaf.

Abstract:The germination and seedling of immature seeds and embryos after anthesis 82~87 d of longan (Dimocarpus longan Lour. ‘Shixia’) were studied. The results showed that the germination and seedling rates of immature embryos sowed directly in clean sand were better than those of in vitro cultured immature seeds. Furthermore, although the germination time of immature embryos stored at 4℃ for 24 hours was slightly delayed in sand, there was no obvious inhibition effect on their germination rate and seedling growth. These results indicated that sowing directly in clean sand was a good way for immature seed and/or embryo rescue in sexual hybridization breeding of longan.

Abstract:The genetic transformation system of cucumber ‘New Jinchun 4’ mediated by Agrobacterium tumefaciens were studied. The cucumber leaves as explants were pre-cultured on MS + 1.0 mg L-1 6-BA + 0.15 mg L-1 IAA for 2 days. After infected by Agrobacterium (OD600=0.8, pH=5.7) for 8 min supplemented with 150 μmol/L acetosyringone (AS), the explants were co-cultured on MS + 1.0 mg L-1 6-BA + 0.15 mg L-1 IAA + 500 mg L-1 Carb + 40 mg L-1 Hyg for 2 days. The hpt gene were transformed successfully to regenerated plantlets by gus instantaneous expression and PCR test.

Abstract:The meiosis and male gametophyte development of Erigeron breviscapus were observed by using squash and transparent preparation technology, and the relationship between the development stage and the flower morphological characteristics was discussed. The results showed that cytokinesis of microspore mother cells in meiosis was simultaneous type, tetrad was tetrahedral, and mature pollen grain was 3-celled. The morphological characteristics of inflorescence and bud had relation to process of meiosis and male gamete development. The stages of meiosis and male gametophyte development could be distinguished according to the length of bud.

Abstract:Sesuvium portulacastrum (Aizoaceae) is a perennial, berbaceous facultative halophyte naturally growing in the tropical and subtropical coastal areas. The advances in mechanism research of Sesuvium portulacastrum under drought, high salinity and heavy metal stresses were reviewed. Meanwhile, its potential value and probably application were also discussed.

Abstract:The main research progresses on Phalaenopsis in vitro culture were reviewed, including explants selection, embryogenesis and protocorm-like body induction, medium, culture condition and method, and browning control, eg. Meanwhile, the bioreactor, genetic transformation, mutation breeding and other biotechnology were summarized. The flower stalk, tip of shoots and seeds from adult plants were common used as explants, and do the leaf, tip of shoots, root tips from tube plantlets. The main factors of explants browning were type of medium, pH, temperature and the physiological state. The researches about mutational breeding and genetic transformation in Phalaenopsis were still at preliminary stage.