Abstract:In order to understand the changes in soil C, N and P in forest succession, the soil organic carbon (SOC), nitrogen (N) and phosphorus (P) and the chemical stoichiometry characteristics were studied in three Dinghushan forests along a succession gradient. The results showed that both the contents of SOC and N decreased along soil depths and increased with succession stages. There were significant differences in contents of soil SOC and N between late succession and early succession (P < 0.05), and also between topsoil (0-20 cm) and other soil layers (P < 0.05). The content of soil P was the highest in middle succession forest, but there were no significant differences among three forests. For the distribution pattern of P along soil profile, the content of soil P increased with soil depth in early succession and decreased in late succession, which had no significant differences among soil layers in middle succession. Soil C:N was not affected by soil depth or succession process, while soil C:P and N:P increased with succession process and decreased with soil depth. It was suggested that the contents of SOC, N, and P with succession process and soil depth depended on the sources of soil C, N, P.

Abstract:In order to understand the gas exchange characters of water and soil conservation tree species, the photosynthetic and transpiration characters of five common urban forest tree species in Hanzhou, including Sapindus mukorossi, Choerospondias axillaris, Cinnamomum camphora, Elaeocarpus glabripetalus and Phyllostachys edulis, were studied. The results showed that the daily dynamic curve of photosynthetic rate (Pn) in Cinnamomum camphora, S. mukorossi, Choerospondias axillaris and P. edulis indicated bimodal type with obvious "noon break" phenomenon, while those in E. glabripetalus indicated single peak type without "noon break". The Pn was in the order of Cinnamomum camphora > P. edulis > S. mukorossi > Choerospondias axillaris > E. glabripetalus, while the transpiration rate (Tr) showed Cinnamomum camphora > S. mukorossi > P. edulis > Choerospondias axillaris > E. glabripetalus, and the water use efficiency (WUE) was E. glabripetalus > P. edulis > Choerospondias axillaris > S. mukorossi > Cinnamomum camphora. Tr, Gs and WUE had significant differences (P < 0.01) among five tree species by ANOVA analysis, while Pn and Ci had not significant difference. Pearson correlation analysis showed that Pn had significant positive correlation with Tr, Gs, PAR, and did Tr with Gs. WUE had significant negative correlation with Tr, Gs, and did Ci with PAR and Ta. Therefore, Cinnamomum camphora and S. mukorossi had high Tr with low WUE, so it was better to strengthen water and shading for reduce Tr in conservation process. P. edulis, Choerospondias axillaris and E. glabripetalus had low Tr with high WUE, showing that they could scientifically use soil moisture and adapt to drought environment.

Abstract:In order to understand the plant community structure in wetlands of Poyang Lake, the species-area relationship of three kinds of marshland plant communities were studied. The plant species number was investigated by nested plot method, and the species-area equations were fitted with 3 unsaturation curves. The results showed that based on the actual data, the number of the species rapidly increased at first with increment of sampling area, and then gradually became stable latter on. The size of 30 m² was determined as the minimum sampling area for the plant community. The fit effects of power function model on species-area relationship among 3 studied communities were the best with RSE of 0.35, 0.35, 0.56, AAD of 0.23, 0.17, 0.35 and AARD of 0.06, 0.02, 0.07, respectively; while those of exponential model and Fisher model were ordinary. Compared with the measured data, the minimum sampling areas under different scaling factors for 3 studied communities calculated by exponential model were the fittest to the actual situation. These would provide theory references for sample establishment in data collection of plant community in Poyang Lake Region.

Abstract:In order to explore the cultivation method of Anoectochilus roxburghii, its growth characters were studied planted at low altitude of 21-23 m in Xinghu National Wetland Park in Zhaoqing, Guangdong. The results showed that the culture location would select evergreen broad-leaf forest with canopy density about 65%. The base matrix included origin soil and peat soil with 1:1 (V/V). The tissue culture seedlings at grade I were selected as plantlets with length of aerial stem ≥ 4.16 cm, and stem diameter ≥ 0.176 cm. The survival rate could reach up to 83.3%-86.7% grown under average temperature of 18.3℃-24.5℃ and relative humidity of 84%-87% in March to April. After transplanted for 120 days, the aerial stem length and fresh weight per plant increased by 3.33 cm and 0.71 g, respectively. With the increment of temperature and humidity in May, the survival rate of A. roxburghii significantly decreased to 70.3%, and insect attack occurred frequently. Therefore, the reasonable cultivation technique under forest would contribute to development and utilization germplasm resources of Anoectochilus roxburghii.

Abstract:In order to understand the seed characteristics and the rhythm of seedling breeding of Tutcheria kweichowensis, the biological characteristics, including seed thousand grain weight, viability, water content and water absorption, the germination rate of seeds under different storage methods, the annual growth rhythm of seedlings were studied. The results showed that the thousand grain weight, viability and water content of seeds were 0.920 kg, 66.17% and 11.75%, respectively, and the maximum water absorption was up to 15.62%. Low temperature wet sand storage could be used for long-term storage, while short-term accelerating germination was suitable for wet sand storage at 25℃, relative humidity 80% for 40 days, seed germination rate could reach more than 80%. The annual growth rhythm of the seedlings was "slow-fast-slow". The active growth period was from May to September, the seedling growth in height and ground diameter accounted for 65.48% and 42.02% of the year, respectively. Therefore, according to the growth characteristics, it would have great significance to improve the seedling quality and production efficiency by adopting different seedling measures in different growth stages, strengthening field management and the supply of water and fertilizer.

Abstract:In order to understand the effect of the environment of tropical coral islands on plant growth, the ecological adaptability of three species grown in tropical coral islands was studied, including Cynodon dactylon, Acacia auriculaeformis and Casuarina equisetifolia. The results showed that the antioxidant enzyme activities, such as SOD, CAT and POD, and proline content in three species grown in coral islands increased significantly (P < 0.05) compared with the same species grown in Seedling Base in Wenchang, Hainan Province. The malondialdehyde content in leaves of A. auriculaeformis and C. dactylon grown in coral islands also significantly increased (P < 0.01), while it had no difference in C. equisetifolia. Therefore, it was indicated that these species would adapt well to the harsh environmental conditions on the coral island through enhanced activities of antioxidant enzymes and increased contents of osmotic adjustment substances.

Abstract:In order to understand the effect of shading on growth and quality of Callicarpa nudiflora seedlings, the photosynthetic characteristics, chlorophyll fluorescence parameter, the content of chlorophyll and total flavonoid of two-year-old seedlings were studied under different shading treatments, including shading 30%, 50%, 70% and 0%, respectively. The results showed that the diurnal variation curve of net photosynthetic rate (Pn) of C. nudiflora was bimodal type under 0% and 30% shading, and with the increment of shading, diurnal variation curve of Pn was from bimodal into unimodal type gradually. The transpiration rate (Tr) and stomatal conductance (Gs) were unimodal type, and the peak value also gradually decreased with the increment of shading. The diurnal changes in PSⅡ maximal efficiency (Fv/Fm) and potential efficiency (Fv/Fo) showed ‘V’ type, those average value under shading treatments were significantly higher than those under 0% shading, and significantly increased (P < 0.05) with the increment of shade. The contents of chlorophyll a (Chl a), chlorophyll b (Chl b), carotenoid (Car) in the leaves significantly increased with the increment of shading (P < 0.05), but the Chl a/b and Car/Chl decreased with the increment of shading, the content of total flavonoids in the leaves increased at first and then decreased, and reached up to maximum under shade of 30%. Therefore, from the photosynthetic characteristics, C. nudiflora seedling would be suitable for growth under 0% shade, but in order to gain high flavonoids, it would be a good choice under 30% shading.

Abstract:In order to understand the relationships of tea cultivars in Fujian Province, the genetic diversities of 43 tea (Camellia sinensis) cultivars were analyzed by using 23 pairs of primers selected from the 38 pairs of SSR markers. Seven pairs of SSR primers with less amplification bands and relatively high polymorphisms were further selected to construct the fingerprints of tea cultivars. Cluster analysis showed that the 43 tea cultivars could be divided into ten groups. The farthest genetic distance is ‘Baxiancha’ and the closest genetic distance is between ‘Fuding-dahaocha’ and ‘Jiulongdabaicha’. The genetic diversity of Oolong tea cultivars was higher than that of green tea cultivars. There was high similar coefficient among cultivars originated from common parents, and usually clustered into the same group. Similarly, the cultivars originated from the same region were usually formed into the same group, while the cultivars with farther geographical distance showed large genetic distance. These would provide references for cultivars selection and genetic improvement of tea tree.

Abstract:In order to gain high yield strain of huperzine A (HupA) from Huperzia serrata (Thunb.) Trev. in vitro, the hydrogen peroxide (H₂O₂) induced thallus was studied. The results showed that the HupA content in induced thallus significantly increased. The strain SH42 had highest yield of HupA with relative growth rate and HupA content for 4499.28% and 261.17 μg g^-1 DW, respectively, which increased 2.35 times and 2.43 times of the initial strain, respectively. Moreover, there were significant difference spectral band in SOD isozymes and soluble protein among strains. The variation characteristics were stable after nine generations. Therefore, it was suggested that H₂O₂ had good induced effect on thallus of Huperzia serrata, which could be used for screening high-yield strain of HupA in vitro.

Abstract:Hoya vangviengiensis Rodda & Simonsson (Asclepiadoideae, Apocynaceae) is reported as newly recorded species from China. The description of the species is also provided. A small number species of Hoya R. Br. being non-laticiferous is introduced. The vouchers are deposited in the Herbarium of South China Botanical Garden, Chinese Academy of Sciences (IBSC).

Abstract:Ophiorrhiza hispida was reported from China in many documents. According the specimens and field investigation, it is misidentification of O. pseudofasciculata.

Abstract:Oligostachyum heterophyllum M. M. Lin, a new species from western Fujian, China is described and illustrated. It is similar or related to O. scabriflorum (McClure) Z. P. Wang et G. H. Ye on morphological characters, but differs in its thin culm with less than 1.5 cm in diam., culm sheaths initially palely purple-green, setose, bases of setae forming persistent papillae and has no spots abaxially, no white powdery and scorched edge, base with densely fine setae; ligule pale stramineous; blade erect, base unshrinked; leaf sheaths puberulous.

Abstract:In order to understanding the relationship between the endangered mechanism and the female reproductive development of Diplopanax stachyanthus Hand.-Mazz., the megasporogenesis and development of female gametophytes were observed by using the paraffin section method. The results showed that the pistil of D. stachyanthus was single carpel, ovary inferior with one locule and one ovule. The amphitropous ovule located on a short flake placenta with single integument and thick nucellus. The single sporogonium differentiated from epidermis of nucellus; the megaspore tetrad was linear. In mature embryo sac, two polar nucleis fused into secondary nucleus before fertilization, three antipodal cells were undeveloped and degraded. The abnormal development happened at 2-nucleate embryo sac stage, two nuclei division was uneven and the small nuclei degenerated and disappeared. Therefore, it was suggested that the abnormal development of D. stachyanthus female gametophyte was the main reason for low setting rate.

Abstract:In order to understand the chemical constituents of Swietenia macrophylla King, thirteen compounds were isolated from its roots. On the basis of spectral data, they were identified as 1,5-dihydroxyxanthone (1), 1,6-dihydroxy-5-methoxyxanthone (2), euxanthone (3), 1,2-dimethoxyxanthone (4), (+) catechin (5), (+) sesamin (6), bis-(2-ethylhexyl) phthalate (7), 3-oxotirucalla-7,24-dien-21-oic acid (8), (20S)-3β-acetoxy-24-methylenedam-maran-20-ol (9), cycloeucalenol (10), β-sitosterol (11), 7-deacetoxy-7-oxogedunin (12) and 7-deacetoxy-7α-hydroxygedunin (13). Among them, compounds 1-4, 6-10 and 13 were isolated from the genus Swietenia for the first time. Moreover, compound 4exhibited inhibitory activity against acetylcholinesterase.

Abstract:To clarify the chemical constituents in strawberry (Fragaria×ananassa Duch.) cv. Falandi, nineteen compounds were isolated from the ethanol extract of its fresh fruits by means of chromatographic separation techniques. On the basis of spectral data, their structures were identified as p-hydroxybenzoic acid (1), ethyl gallate (2), ellagic acid 3-O-α-L-rhamnoside (3), benzyl β-D-glucoside (4), icariside F2 (5), benzyl 6-O-α-L-arabinofuranosyl-β-D-glucoside (6), phenethyl 6-O-α-L-arabinofuranosyl-β-D-glucoside (7), trans-cinnamoyl β-D-glucoside (8), cis-cinnamoyl β-D-glucoside (9), trans-p-coumaroyl β-D-glucoside (10), cis-p-coumaroyl β-D-glucoside (11), trans-feruloyl β-D-glucoside (12), kaempferol (13), trans-tiliroside (14), kaempferol 3-O-β-D-glucuronide (15), quercetin (16), quercetin 3-O-β-D-glucoside (17), quercetin 3-O-β-D-glucuronide (18), and phloridzin (19). Compounds 1-12 belong to aromatics and the others are flavonoids. All of them were reported from cv. Falandi and compounds 4-9 from strawberry for the first time.