Abstract:The seedlings of 4 dominant tree species of tropical seasonal rain forest, such as Pometia tomentosa, Barringtonia macrostachya, Myristica yunnanensis and Knema globularia, were transplanted at three altitudinal sites (low 600 m in Menglun; middle 1 100 m in Caiyanghe; high 1 600 m in Mengsong) in Xishuangbanna. The parameters of photosynthesis and biomass of these seedlings were measured. The results showed that the low temperature at high altitude caused dormancy or photosynthetic system destroy. The maximum photosynthesis rate (Pmax) and dry biomass of four seedlings declined significantly along the increment of elevation. The diurnal change pattern of photosynthetic rate of four seedlings at low and middle altitude both showed double-peak type, which the first peak appeared at 11: 00~12: 00 am and the next peak at 4: 00~5: 00 pm, and the first peak was higher significantly at low altitude than that at middle altitude. Except for K. globularia, the root biomass fraction (RMF) of seedlings of the others increased with the increment of altitude. It is concluded that the biomass and photosynthetic rate of these seedlings are mainly limited by temperature, which is the potential reason that these species disappeared in rain forest community at high altitude. Furthermore, It is an important characteristic adapted to limited environmental temperature that RMF of four seedlings increased with the increment of altitude.

Abstract:The physiological and ecological characteristics, and nutrient utilization of Bauhinia corymbosa were studied by plot investigation. The species is a heliophyte liana and distributes mainly in open forest fringe, hillside, and village side in tropical and subtropical areas, and grow well on the red soil and lateritic red soil. The average photosynthetic rate, stomatal conductance and transpiration rate were 3.306 μmol m-2s-1, 0.25 mol m-2s-1 and 4.10 mmol m-2s-1, respectively. The weighted nutrient contents of N, P, K, Ca, Na, and Mg in B. corymbosa were 1.11%, 0.09%, 0.56%, 0.86%, 0.21% and 0.06%, respectively. The nutrient utilization efficiency of B. corymbosa is high and N content in leaf is the highest, and do Na content in branch, P and Mg contents in root. The ecological and biological characteristics of B. corymbosa were beneficial to growing, climbing and adapting to environment.

Abstract:To accumulate the information for research on diffusion mechanism and ecological effect of Oenothera laciniata Hill, the community invaded by O. laciniata in Wenzhou, Zhengjiang Province and the seasonal dynamics of specie composition in soil seed bank were studied based on field investigation and germination experiment. The results showed that there were 46 species in the soil seed bank, and the species richness and their abundance among the soil layer showed remarkable difference, in the order as 0~2 cm>2~5 cm>5~10 cm. The Sorensen’s similarity coefficient for species composition aboveground and in the seed bank was 0.632, showing that the invaded community was at the initial stages of succession. The seed of O. laciniata had a characteristic of dormancy, and seed could periodically break dormancy at the process of bud. The importance value of O. laciniata in the community had positive correlation with the species diversity of community, but not significantly (P>0.05). It is proper time to control the spread of O. laciniata by eradicating it at its vegetative growth phase from November to next April .

Abstract:The relationships between modules Modular and biomass of Dendrocalamus minor var. amoenus were studied. The results showed that diameter at breast height (DBH) had significant correlation with other components. The DBH was linear to total height (H), height under branch (L), with R2=0.5017，Radj2=0.4741，F＝18.13，P＝0.0005, R2=0.7804, Radj2=0.7682,F＝63.9525, P<0.0001, respectively, and had quadratic polynomial relation to wall thickness ratio, with R2=0.7728，Radj2=0.7559，F=45.9109，P<0.0001. The relationship between organ biomass and DBH, H were significant, and the stepwise regression model (R2>0.66，F>15，P<0.0052) was established of 1~4-year-old bamboo. It indicated that the biomass of 1- and 2-year-old individuals were determined by DBH and H, while those of 3-, and 4-year-old individuals were only by DBH.

Abstract:Energy characteristics of 6-year-old trees of Eucalyptus grandis, E. saligna, E. cloeziana, E. pellita and E. torelliana in Zhangmutou Forest Farm in southern Guangdong Province were studied. The results showed that there were significant differences in ash content and caloric value of various above and below ground components (P<0.01). Ash contents ranged from 0.16% to 8.37%, with the components in E. grandis, E. saligna, E. pellita and E. torelliana had order as leaves> bark>branches> roots>stem-wood, and that in E. cloeziana as bark>leaves>branches>roots>stem-wood. Gross caloric values (GCV) of various components ranged from 15.12 to 18.85 kJ g-1 with leaves having the highest GCVs and bark the lowest. For E. grandis and E. pellita, the order of components was leaves>branches> stem-wood>roots>bark, for E. saligna and E. torelliana was leaves>stem-wood>branches>roots>bark and for E. cloeziana leaves>branches>roots>stem-wood>bark. Ash free caloric values (AFCV) of components ranged from 16.37 to 19.87 kJ g-1 and the order of components by AFCVs were the same as those for GVCs for E. grandis, E. saligna, E. cloeziana and E. torelliana, and that for E. pellita as leaves>branches>bark> stem-wood >roots. For whole tree, E. grandis and E. pellita had the highest mean GCV and AFCV values respectively, while E. torelliana had the lowest.

Abstract:The conserved region of β-Gal gene of papaya (Carica papaya L.) pulp was cloned, which encoded a key enzyme of β-galactosidase involved in the cell wall degradation. The RNAi intermediate expression vector of pKAN/RG was constructed containing β-Gal gene in an inverted repeat orientation with the help of pKANNIBAL vector. hptⅡ gene of the modified pCAMBIA 1300 vector was replaced by the hairpin structure of pKAN/RG, which resulted in the formation of intermediate expression vector of p1300-/MFRG. Single T-DNA region of p1300-/MFRG was isolated and incorporated into the pCAMBIA 2301 vector to produce the RNAi Two-T-DNA plant expression vector of p2301/TTRG. The transformation of p2301/TTRG into Agrobacterium tumefaciens EHA 105 was confirmed by restriction enzyme analysis and PCR assay. The embryogenic calli of papaya which had kanamycin resistance and GUS expression were obtained by genetic transformation.

Abstract:The finger map of longan (Dimdcarpus longan Lour. ‘Honghezi’) cotyledon embryo RNA was established by cDNA-AFLP, which extracted from thirty-five-day (early) and fifty-day (late) cotyledon embryos after anthesis, respectively. There were 41 differential fragments cloned and sequence analysed, in which 21 differential expression fragments had high homology with some known genes, the function mainly involved in the abaxial polarity of lateral organ, glycolysis, energy metabolism, ion transport, cell wall elongation, cell cycle regulation, RNA transcription, RNA translation and regulation, protein phosphorylation regulation and protein degradation, signal transduction and so on. While the others had low or no homology with known genes.

Abstract:Plant regeneration through callus induction were established by using young sheath of fruit sugarcane (Saccharum officenarum ‘Badila’), and the transformation of calli mediated by Agrobacterium tumefaciens was studied. The optimum media were MS + 2.0 mg L-1 2,4-D for calli induction, MS + 2,4-D 2.0 mg L-1 + 6-BA 1 mg L-1 for differentiation; and MS + IAA 2.0 mg L-1 for root induction, respectively. Plant expression vector pMG225, including cryIA gene and CPTI gene, was transformed into calli of fruit sugarcane by Agrobacterium tumefaciens. It confirmed that cryIAc gene had been integrated into fruit sugarcane genome by PCR and Southern blot analysis.

Abstract:The component and stability of anthocyanidins in petals of sixteen Freesia refracta cultivars were analyzed by the specific color reactions and UV-visible spectrum. The results showed that the petal anthocyanidins in all cultivars belonged to flavonoids, including flavones, anthocyanins substance, and might contain isoflavones, but no flavonols, flavanones, flavanonols, chalcones and aurones. The cultivar of yellow petals lines also contained carotenoids. The anthocyanins under dark were more stable than that under light. And there were some effects of temperature on the stability of petal anthocyanidins.

Abstract:The effects of exogenous Se on the topography and quantitative characters of Agaricus brasiliensis S. Wasser fruit bodies were studied under scanning electronic microscope (SEM). When exogenous Se was 30 mg kg-1, the length, width and number of spores of Agaricus brasiliensis S. Wasser increased by 20.92％, 5.41％ and 114.13％, respectively, and had significant difference (P<0.01) to the control. When treated with 10 and 20 mg kg-1 Se, the maximum and minimum diameters and number of the cystidium increased by 34.78％ and 7.73%, 13.40％ and 15.26％, 27.78％ and 33.33％ (P<0.01), respectively, and the minimum width of the mycelium increased by 45.90％ and 50.82％ (P<0.01), respectively. The morphological structures of the spore, cystidium and mycelium varied under SEM.

Abstract:Under the artificial climate incubator, the effects of seed coat and temperature on the germination of Hevea brasiliensis seeds were studied. The results showed that seed coat had significant mechanical inhibition on the water absorption and the germination of H. brasiliensis seeds. The seed germination sped up and germination index increased when removed seed coat, but germination rate significantly decreased from 83.8% to 47.85%, and vigor index from 332.3 to 187.9, respectively. The seed germination delayed obviously and the germination rate reduced under below 15℃. The germination rate, germination index and vigor index of kernel all increased with the elevation of temperature, while those of seeds were up to peak at 20℃(94.7%), 30℃(1.86), and 25℃(374.4), respectively. The coefficient of germination rate increased first, and then decreased. In the rubber cultivation and the construction of rubber plantation, the restrict effect of seed coat on water lose of kernel and non-sensitivity to lower temperature could be utilized to prolong seed storage period, increase germination rate and improve seedling quality.

Abstract:A floristic study of the Tongledashan Nature Reserve in Yunan County, Guangdong Province, China was carried out. The seed plants are found to be abundant in this area, represented by 1 002 species belonging to 542 genera in 149 families. This flora, composed mainly of phytogeographical elements from the northern border of the Chinese southern subtropical and tropical regions, is characterized by rich floristic components and complex phytogeographical elements. In addition, there are a plenty of rare, endangered, and endemic species in this area, indicating the ancient origin of this flora. Compared with its neighbouring floras, the flora of the Tongledashan Nature Reserve is closely related to those of Longhushan Nature Reserve in Guangxi, and Heishiding Nature Reserve in Guangdong，but only distantly related to that of the Wulingyuan Nature Reserve in Hunan.

Abstract:A new species of Gesneriaceae, Chirita pseudoheterotricha T. J. Zhou, B. Pan & W. B. Xu, from limestone areas in Guangxi, China, is described and illustrated. The new species is similar to C. heterotricha Merr. in leaf shape, but differs in its internodes of rhizome 2~8 mm long, leaf blade and petiole densely glandular- pubescent on both surfaces, lateral veins 3~4 on each sides, inflorescence spreading glandular-pubescent, calyx-lobe lanceolate, corolla-lobe oblong, filaments twisted at the middle, densely purple glandular-puberulent.

Abstract:Based on the field expedition within recent years in Fujian Province，the new records of vascular plants were discovered. The two newly recorded genera are Brasenia Schreb. and Asyneuma Griseb. et Schenk., and the six newly recorded species are Brasenia schreberi J. F. Gmel.，Asyneuma chinense D. Y. Hong, Garcinia oblongifolia Champ. ex Benth., Dicranopteris tetraphylla (Rosenst.) C. M. Kuo, Dalbegia benthamii Prain, Galium paradoxum Maxim. The new records have been described in detail.

Abstract:The chromosomes of two new varieties ‘Yunyan 77-2’ and ‘Yunyan 77-4’ and their parents ‘PR107’ and ‘GT1’ were observed, and the breeding process of the new varieties was summarized. The results showed that the chromosome number of ‘PR107’ and ‘GT1’ is 2n=2x=36, whereas 2n=3x=54 for ‘Yunyan 77-2’ and ‘Yunyan 77-4’. ‘Yunyan 77-2’ and ‘Yunyan 77-4’ are triploids. It is an effective way to breed new Hevea varieties by establishing a pollination garden of special parents, setting reasonable screening criteria and selecting the polyploid seedlings under stress circumstances.

Abstract:By using paraffin method, the root anatomical structure of Philodendron pitfieri Engl. under water culture were observed, and the morphological characteristics adapting to aquatic environment were discussed. The results showed that compared with soil culture, the root cap was not obvious with less amyloplast and polysaccharose substance under water culture. The root epidermis under water culture was thinner than that of soil culture, with little root hair or not, in which cortex parenchyma tissue developed with big cell, solution proliferative aerenchyma in intercellular space, and thin cell wall. However, the root cap under soil culture was big, with strong PAS reaction and no aerenchyma tissue.

Abstract:Twelve compounds were isolated from the aerial parts of Pogostemon cablin （Blanco ） Benth. On the basis of spectral data, they were identified as: apigenin(1), 3,5,4'-Trihydroxy-7-methoxyflavone (2), 5,7-Dihydroxy-3,4'-dimethoxyflavone (3), apigenin 7-galacturonide (4)，apigenin 7-(O-methylglucuronide) (5), luteolin 7-O-(6-O-methyl-β-D-glucuronopyranoside)（6）， 4',5-Dihydroxy-3',7-dimethoxyflavanone (7), quercetin-7-β-D-glucoside (8) 3,23-dihydroxy-12-oleanen-28-oic acid (9), syringaresinol-β-D-glucoside (10), verbascoside(11), orobanchoside（12），campneoside I (13). Compounds 2～13 were isolated from this plant for the first time.

Abstract:The chemical constituents extracted from tubers of Polygonum multiflorum Thunb. originated from Deqing of Guangdong Province were isolated by using chromatographic techniques. On the basis of spectral data, eight phenolic components were identified, such as physcion-8-β-D-(6′-O-acetyl)glucoside (1), physcionin (2), emodin (3), epicatechin (4), torachrysone 8-O-β-D-glucopyranoside (5), 2,3,5,4′-tetrahydroxystilbene 2-O-β-D-glucopyranoside (6), 4-hydroxybenzaldehyde (7), 5-carboxymethyl-7-hydroxy-2-methylchromone (8). Compounds 1, 7 and 8 were isolated from this plant for the first time.

Abstract:The reasons of dormancy, methods of breaking dormancy, and the effect of environment factors on dormancy and germination of Rosa seeds were analysed. There were some resons caused Rosa seeds dormancy, such as the restriction of pericarp and testa, physiological dormancy in embryo and inhibitory substances in pericarp, testa and embryo. Therefore, breaking dormancy methods in some Rosa plants were also reviewed, including derestriction and removing inhibitory substances, etc. The environment factors, such as temperature, water and light had important effects on seed dormancy and germination during development and ripening stages. Otherwise, microbial action and the time of hip collection affected seed dormancy and germination of Rosa plants. The dormancy mechanism of Rosa seeds was complex, and had great differences among various Rosa species.