Abstract:In order to understand the difference in soil water use of Schima superba in dry and wet seasons, the sap flux densities (Js) of S. superba were continually monitored using Granier's thermal dissipation probes (TDP). Based on the measurements of leaf water potential (Ψ_L), parameters of hydraulic structures, such as leaf area index (LAI), and Huber value (A_S:A_L), in combination of the synchronized monitoring environment factors, the dry/wet seasonal changes in whole-tree hydraulic conductance (K_L), canopy stomatal conductance (G_S) and effective water storage for transpiration (Q) of S. superba were analyzed. The results showed that the soil water deficit in the dry season increased the resistance of water absorption and transpiration of S. superba. However, the G_S of S. superba was sensitive to the vapor pressure deficit (VPD) to keep midday leaf water potential (Ψ_L-mid), water potential gradient between leaves and the soil (ΔΨ_S-L) in dry and wet seasons. Moreover, the LAI、K_L and G_S of S. superba decreased to effectively regulate transpiration in the dry season. Meanwhile, the high contribution of effective water storage for transpiration (Q) to daily transpiration and Q per unit leaf area in the dry season would partially compensate the water stress. Since the S. superba plantation could maintain a vigorous transpiration with those adaptive regulations in the dry season during which it still had sufficient solar and thermal resources in south China, the whole-tree water use per unit leaf area of S. superba in the dry seasons was kept similar to that in wet seasons. Therefore, it was suggested that the regulating of K_L and G_S, the hydraulic compensation effect of Q, and the hydraulic characteristics, could to some extent explain that the whole-tree water use per unit leaf area of S. superba remained constant in the dry and wet seasons, and SWC had no significant effect on transpiration.

Abstract:In order to understand seasonal dynamics in soil microorganism community of evergreen broad-leaved forest in Wuyi Mountains, Fujian, the microbial diversity in soil was analyzed using the Illumina Miseq high-throughput sequencing technique. The results showed that the soil in evergreen broad-leaved forest in Wuyi Mountains was the typical southern acidic soil. The soil physic-chemical properties had no significant difference among four seasons except for the available potassium, soil temperature and pH. The diversity of soil microorganisms is very rich, and 206 bacterial genera belonging 23 phyla and 17 archaea genera belonging the phyla Thaumarchaeota and Euryarchaeota were identified. The Chao index reflecting the number of bacterial was the highest in the summer, while the Shannon index reflecting bacterial diversity in the summer was lower than that in the spring by 21%. Moreover, the Chao index and Shannon index for archaea in the summer were higher than those in the winter by 21.7% and 0.27%, respectively. There were 83.1% bacteria and 70.0% archaea shared in four reasons, suggesting a good stability of the core microbiome in different reasons in evergreen broad-leaved forest in the Wuyi Mountains. Clustering tree analysis at both of phylum and genus levels indicated that bacterial and archaea community of spring was very close to that of winter, while that of summer exhibited the most different to those of the other three seasons. Heatmap and redundancy analysis indicated that the soil pH was the main environmental factors affected the diversities of bacteria and archaea. The effective potassium, effective carbon and total nitrogen have a great influence on microbial community composition. Therefore, the diversity of soil microorganisms in evergreen broad-leaved forest in Wuyi Mountain had regular changes with the seasons.

Abstract:In order to understand the temporal and spatial distribution pattern and stoichiometry characteristics of carbon, nitrogen, phosphorus in litter and soil of Eucalyptus plantation, the contents of carbon, nitrogen, phosphorus in litter and soil of E. urophylla×E. grandis plantation under five forest ages were analyzed. The results showed that the C content in litter was significantly higher than that in soil, and had no significant difference among forest ages. The C content in surface soil (0-20 cm) at 1-year-old forest was the lowest, and that in other soil layers had no significant difference among forest ages. The N content of litter was higher significantly than that in soil, and which at 1-year-old forest was the highest. The N content of surface soil in 7-year-old forest was the highest, which in 1-year-old forest was the smallest. The P content of litter had no significant difference among forest ages except 1-year-old forest was obviously bigger than 3-year-old forest. The P content in soil had no significant difference among forest ages. The C:N in litter increased with forest ages, which was significantly higher than that in soil. The C:N, N:P in litter had no significant difference among forest ages, which were higher than soil. The N content in litter was negatively correlated with C and N contents in soil, and there were significant relation between C:N in litter and C:P, N:P in surface soil. The C and N accumulation in surface soil was restricted by N content in litter. Therefore, it was important in sustainable management of Eucalyptus plantation for reduce N limitation in litter, increase nutrient transfer efficiency and rational application of fertilizer.

Abstract:In order to establish induction system of hairy roots of Sedum alfredii, the leaves infected by Agrobacterium rhizogenes A4 as explants, the effect factors, such as pre-culture time, infection time and co-culture time, on induction rate of hairy roots were studied. The results showed that the hairy roots could be induced after 48 h pre-culture, infection for 6 min and 48 h co-culture with the highest induction rate of 85%. Furthermore, the rolB gene could be detected in induced hairy roots by PCR, which confirmed that the transgenic system of S. alfredii mediated by A. rhizogenes A4 was successful. So, it was the first time for induction system establishment of hairy roots in S. alfredii with A. rhizogenes A4.

Abstract:In order to understand the tolerance of cockscomb (Celosia cristata) seeds under short-term extreme high temperature for 30 min, the seed vigor and physiological indexes of early seedlings were studied by germination on paper. The results showed that the relative germination rate, germination energy and relative germination index of cockscomb seeds treated under 60℃ were 101.68%, 70%, 101.41%, respectively, and the relative harm rate was only-1.14%. The root length, lateral root number, root activity, chlorophyll content, SOD activity and MDA content of early seedlings had not significant difference with the control (P>0.05), but POD and CAT activities were significantly higher than the control (P<0.05). The seed vigor, CAT activity, root activity and chlorophyll content decreased with higher temperature. Therefore, the limiting temperature that cockscomb seeds could tolerant was 60℃, the CAT in cockscomb seeds was more sensitive than SOD and POD under high temperature, which could be used as an index to evaluate the reaction of plants to short-term high temperature.

Abstract:In order to understand the genetic relationship among of Asparagus officinalis L. germplasms, the genetic diversity of 19 asparagus parents were analyzed by ISSR. The results showed that 187 bands were amplified by 18 primers with polymorphism rate for 93.6%. UPGMA indicated the Nei's coefficient ranged from 0.56 to 0.80. These cultivars could be clustered into three groups according to average coefficient of 0.62. Asparagus officinalis ‘Green Dragon’ cultivar from US formed GroupⅠwhich had far relation with others. Group II consisted of some artificial breeding parents of ‘Gijnlim’ from Holland and ‘Grande’ from US. The other tested parents made up the Group III. The individuals derived from the same variety had large genetic distance. There were abundant genetic diversity among individuals of asparagus from ploidy breeding. Therefore, these would provide the theoretical basis and technical guidance for parent selection in hybrid breeding of asparagus.

Abstract:In order to understand the characteristics of cellulase in shoots of Camellia sinensis, the changes in cellulase activity and related gene expressions in three cultivars of C. sinensis were studied. The results showed that the cellulase activity in the three cultivars had significant difference. The activities of the endo-glucanase and exo-glucanase in ‘Pingyang Tezao’ and ‘Fuzao No. 2’ increased with leaf maturity, which was contrary to the ‘Shuchazao’. The β-glucosidase activity in the three cultivars was the lowest at stage of three leaves with a bud, and its activity in young parts was higher than that in maturity parts in shoots. Otherwise, the activity of β-glucosidase in tea shoots was higher than that of exo-glucanase. The expresions of five cellulase-related genes could be detected in shoots of three cultivars by semi-quantitative PCR, in which the expression of two homologous genes had significant difference. Therefore, the glucanase would play a role in quality formation of tea.

Abstract:The interaction between pollinating fig wasps (Agaonidae) and their host fig trees (Ficus, Moraceae) is a striking example of an obligate pollination mutualism. The effect factors on number and sex ratio of offspring wasps were studied by using F. hirta Vahl-waps (Valasia javana Mayr) system. The results showed that the community of fig wasps offspring had significant changes in different seasons. The number of pollinator offspring changed caused by non-pollinating fig wasps and foundress interference derived from season. The foundress interference increased sex ratio of offspring fig wasps significantly, but non-pollinating fig wasps had no effect on sex ratio. In addition, the survival time of pollinating wasps at female phase was about 15 h and the development time of pollinating wasps had significant difference between dry and wet seasons, which was long in dry season and short in wet season. Therefore, it was suggested that the pollinators of Ficus hirta had evolved the reproductive strategies to adapt seasonal change in Guangzhou.

Abstract:Habenaria lindleyana Steud., a newly recorded species of Habenaria from Guangxi, China is reported. Its morphological description and photos are provided. The vouchers are deposited in the Herbarium of Guangxi Institute of Botany, Chinese Academy of Sciences (IBK).

Abstract:Coelachne japonica Hack. (Gramineae) was reported as a newly recorded species in China, and it was found in Juxi of Cangnan Xian and Huangqiao of Taishun Xian in Zhejiang Province. According to the records, this species was endemic to Honshu and Kyushu of Japan. The main morphological characters, habitat, photographs and voucher specimens were provided for identification, and Coelachne from Zhejiang was revised.

Abstract:Sidastrum Baker f. (Malvaceae) is reported as a newly naturalized genus in China. Sidastrum micranthum (A. St.-Hil.) Fryxell was found in Guangdong, China for the first time. The voucher specimens are deposited in Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences, Hainan (ATCH).

Abstract:In order to understand the chemical constituents of Clerodendranthus spicatus (Thunb.) C. Y. Wu, eleven compounds were isolated from its aerial part cultivated in Hainan. On the basis of spectral data, their structures were identified as: vomifoliol (1), (-)-syringaresinol (2), 3,4-dihydroxyphenylethl alcohol (3), sinesetin (4), 5,6,7,4'-tetramethoxyflavone (5), 5-hydroxy-6,7,3',4'-tetramethoxyflavone (6), 6-hydroxy-5,7,4'-trimethoxyflavone (7), 5-hydroxy-6,7,3',4'-tetramethoxyflavanone (8), 3,3',5-trihydroxy-4',7-dimethoxyflavanone (9), pinoresinol (10) and ursolic acid (11). Compounds 3, 9 and 10 were obtained from this species for the first time. The compounds 3-5 exhibited inhibitory activity against acetylcholinesterase.

Abstract:In order to understand the chemical constituents of Dendrobium sinense, ten compounds were isolated from whole herb by column chromatography. On the basis of spectral data, their structures were identified as chrysotoxine (1), 2',4'-dihydroxy chalcone (2), 2,5,7-trihydroxy-4-methoxy-9,10-dihydrophenanthrene (3), 4,7-dihydroxy-2,3-dimethoxy-9,10-dihydrophenanthrene (4), 2,5-dihydroxy-3,4-dimethoxy-9,10-dihydrophenanthrene (5), 2,7-dihydroxy-3,4,6-trimethoxy-9,10-dihydrophenanthrene (6), (E)-coniferyl aldehye (7), trans-p-hydroxylethyl cinnamate (8), p-hydroxyphenylpropionic methyl ester (9) and lasiodiplodin (10). All the compounds were obtained from this plant for the first time. Compounds 2, 6, 7 and 10 had a certain inhibitory activity on acetyl-cholinesterase.

Abstract:In order to understand the chemical constituents from Lentopodium lenotopodioides (Asteraceae), eight phenylpropanoids were obtained from its whole herbs by multiple chromatographic separation techniques. On the basis of spectral data, their structures were identified as dihydrodehydrodiconiferyl alcohol 4-O-β-d-glucoside (1), dihydrodehydrodiconiferyl alcohol 9'-O-β-d-glucoside (2), dehydrodiconiferyl alcohol 9'-O-β-d-glucoside (3), dehydrodiconiferyl alcohol 9'-methyl ether-4-O-β-d-glucoside (4), (-)-pinoresinol 4-O-β-d-glucoside (5), (-)-medioresinol 4-O-β-d-glucoside (6), citrusin C (7), and caffeic acid (8). Compounds 2-7 were obtained from this species for the first time. The inhibitory rates of these compounds toward α-glucosidase were less than 50% at the concentration of 500 μmol L^-1.

Abstract:The nature environment affects plants mainly in the aspect of climate, hydrology, soil and terrain. On large scales, climate type obviously affects the zonal distribution and spatial patterns of plant species. On medium and small scales, soil, hydrology, topography and their interaction usually affect the necessary environment and resource condition for plant growth, and even becoming decisive factors on species diversity in plant community. Multivariate quantitative analysis is an important method in researching ecology relationship of plant community, and plays a key role in revealing the relationship between plant community and environment. As a powerful tool of quantitative analysis, ordination methods often play an important role in studying plant ecology, which become a trend in applying to plant community distribution and community structure. The application of ordination methods was reviewed from the angle of plant community distribution and community structure, the main problems were analyzed, and the development direction in future was proposed, so as to provide references for the choice of ordination methods in the future.