Abstract:The structure, species composition and seasonal dynamics of benthic diatom assemblages in two kinds of wetland, mangrove and reed wetland, in Qi’ao Island, Zhuhai were investigated from March 2007 to January 2008. Samples of surface sediment layer (5 cm) were collected and detected under microscope. There were 113 taxa benthic diatom belonging to 28 genera, of which 95 taxa in mangrove and 42 taxa in reed wetland. Abundance of benthic diatoms ranged from 14.3 to 553.5 cells cm-3. The diversity indices and evenness index varied greatly in different sites and sampling time, but those in mangrove were higher than those in reed wetland. Species composition significantly differed in the two sites. Pennales, such as species from Gyrosigma, Pleurosigma and Pinnularia were dominant in the mangrove, while Centrales dominated in the reed wetland, such as Cyclotella and Coscinodiscus. Analysis of similarity indicated that the effects of site sediment were more important than that of season.

Abstract:The distribution of cyanobacteria and microcystin in two pumped storage reservoirs, Fenghuangshan Reservoir and Nanping Reservoir in Guangdong Province was bimonthly investigated in 2008. Forteen genera were identified, and most of them were filamentous and colonial ones, such as Pseudanabaena, Limnothrix, Dactylococcopsis, Cylindrospermopsis and Chroococcus. Cyanobacteria abundance in two reservoirs ranged from 119 to 137373 cells mL-1, and microcystin concentration from 0 to 2.26 μg L-1. In Fenghuangshan Reservoir with relatively long retention time (160 d), microcystin concentration was lower than the national standard for drinking water of 1 μg L-1 throughout the year, which the maximum was in March. In the short retention time (60 d) reservoir, Nanping Reservoir, the concentration of microcystin was higher than that in Fenghuangshan reservoir in the flood season with the maximum in July. In Fenghuangshan Reservoir, the abundance of cyanobacteria was one order higher than that in Nanping reservoir. Maximal abundance occurred in dry season (March) in both the reservoirs, and nutrient loading related to pumping strategy and temperature were two possible factors in seasonal variation of cyanobacteria abundance. In Fenghuangshan Reservoir, Pseudanabaena, Limnothrix and Cylindrospermopsis were dominant in cyanobacteria and contributed more than 50% of the total abundance at most of time. In Nanping Reservoir, cyanobacteria was dominated by filamentous species in dry season and by colonial species in flood season. The temperature and nutrient loading related to pumping strategy seemed to key factors inducing cyanobacteria seasonally dominated by different ecotypes of species in Nanping Reservoir.

Abstract:Southern China suffered one of the most destructive frozen rain and snow ever since 1954, from the middle of January to early February in 2008. The damage status and crown debris amounts of natural secondary forests of Chebaling Nature Reserve and Tianjingshan Station of Nanling National Nature Reserve in northern Guangdong Province, were investigated after the disaster. The results showed that the natural secondary forests were damaged heavily, with the broken of branch, top and stem of the big trees, and stem bent of the smaller trees commonly. The proportions of uproot trees were increased with slope degree increasing. The total standing crop of crown debris in forests ranged from 38.12 to 43.52 t hm-2 with an average of 41.25 t hm-2. The leaf litter varied from 11.79 to 12.87 t hm-2 with an average of 12.47 t hm-2. The total amounts of woody debris of branch and trunk by the disaster varied from 24.27 to 30.65 t hm-2 with an average of 28.41 t hm-2. The crown debris of natural evergreen broadleaved forest caused by the disaster were significantly more than that of the evergreen and deciduous broadleaved mixed forest and Chinese fir plantation. The disaster increased litterfall debris in short period, which will not only increase dangers of fires, pests and diseases, but also change the structure and function of the forest ecosystem.

Abstract:The root and shoot growth, root biomass, and root distribution of four species, such as Cyperus flabelliformis, Hymenocallis littoralis, Phragmites australis, and Vetiveria zizanioides, were studied in a surface-flow constructed wetland. The results showed that root and shoot growth pattern were similar among C. flabelliformis, V. zizanioides, and H. littoralis, with a fast growth stage before September or October, and a slow growth stage during the following months, while P. australis was very different, with slow growth of root and shoot before July, and rapid growth maintained throughout winter. H. littoralis exhibited significantly faster root growth and significantly larger root biomass than other species (P<0.01), while V. zizanioides showed significantly slower root growth and a significantly smaller root biomass than other species (P<0.01). Roots of V. zizanioides generally grew vertically, while the roots of the other species were predominantly distributed in the shallow layer of the substrate. C. flabelliformis produced the most tillers, and had the highest leaf area index (LAI), while V. zizanioides showed the smallest LAI. The results suggest that P. australis could be planted with other wetland species to achieve high decontamination rates in treatment wetlands during the autumn and winter months. Results also suggest that H. littoralis, a lower stratum plant, could be paired with tall and early growing species like C. flabelliformis as a beneficial component of the poly-cultivated wetland community.

Abstract:The spores of Hypodematium crenatum (Forssk.) Kuhn were artificially cultured, and the spore germination and gametophyte development were observed under the microscope. Spores were bean-shaped in equatorial view and elliptical in polar view, monolete, perispore with folds, dark brown. The spore germination belonged to the Vittaria-type, while the gametophyte development is Aspidium-type. The mature prothallium was cordate and bearing two kinds of trichomes (papillary and long needle-like). The rhizoids were bifurcated and enlarged. The mature prothallium is bisexual. The antheridia consist of 3 cells and varied antheridia at different developmental stages occurred on one prothallium. The archegonia are long and always curved to growing point. The characteristics of spore germination and gametophyte development of H. crenatum was relatively advanced and showing a highly adaptation to the limestone environment.

Abstract:Four bamboo species have been flowering in recent years in the garden of Bamboo Research Institute of Nanjing Forestry University. The floral morphology of 4 bamboo species, Shibataea chinensis, Arundinaria simonii f. heterophylla, Chimonobambusa sichuanensis, Arundinaria amabilis var. convexa, are described and supplemented. Among them the flowering characteristics of Shibataea chinensis and Arundinaria simonii f. heterophylla are provided for the first time.

Abstract:After examining the type specimen Elmer 12785, it reveals that Hypoestes pulgarense Elmer is different from other Hypoestes Soland ex R. Br. in its solitary or few flowers clustered in leaf axils and bithecous anthers spurred on lower thecae and is a member of Justicia L. Therefore, a new combination, Justicia pulgarensis (Elmer) C. M. Gao & Y. F. Deng, is proposed herein.

Abstract:Two new species, Rhododendron eriobotryoides Xiang Chen & Jia Y. Huang and R. jinboense Xiang Chen & X. Chen (Ericaceae), from Guizhou Province, China are described and illustrated. Rhododendron eriobotryoides is close to R. denudatum from which it differs by having thinner and sparser flocculence on the leaf blade abaxial surface, puberulent filaments, and a glandular style. Rhododendron jinboense differs from the most morphologically similar species R. brevinerve by the former’s oblong-elliptic and U-shaped leaf blades, a more floriferous inflorescence, a longer corolla, puberulent filaments, and a densely tomentose ovary. Both of the new species are Critically endangered, (CR), based on the IUCN Red List Categories and Criteria, therefore, careful protection is highly desired.

Abstract:The diversities of earth- and rock-type bryophytes in Baili Azalea National Forest Park, Guizhou Province were studied. The results showed that there were 57 species bryophytes, belonging to 34 genera and 17 families, in which 35 earth-type species to 27 genera and 35 families, and 19 rock-type species to 12 genera and 10 families, 3 species facultative. The species similarity coefficient between two types was 0.22. Probability of interspecific encounter index and Shannon-Wiener index were low, while Simpson index was relatively high. It suggested that the bryophyte distribution in Baili Azalea National Forest Park was significantly influenced by substrates.

Abstract:The orchid diversity from Jinfo Mountain Nature Reserve, Chongqing, South China was studied. The results showed that 114 species orchids belonging to 48 genera distributed in Jinfo Mountain Nature Reserve, in which 47 species endemic to China and 3 species endemic to Jinfo Mountain. Vertical distribution pattern of orchid was obvious. The threatened status of orchid was significant different in different altitude. The species at low altitude were less threatened than those at high altitude. Some strategies were proposed for in situ conservation of orchid diversity in Jinfo Mountain Nature Reserve.

Abstract:9-cis-epoxycarotenoid dioxygenase (NCED) is the key enzyme of ABA biosynthesis in higher plant. The expression vector 35S∷AhNCED1∷GUS for peanut (Arachis hypogaea L.) was constructed. Then AhNCED1 gene was transformed into cotyledon of ‘Shanyou 523’, which is sensitive to drought stress, by immersing into Agrobacterium tumefciens strain LBA4404 bacterial suspension solution. The induction rate of adventitious buds with kanamycin-resistant was 100%, and in which there were 48.3% and 50% positive plantlets by PCR amplification and GUS histochemical identification, respectively. The ABA contents in aboveground organs of transgenic plants were higher than that in the wild (non-transformation) plants. When the leaves of the transgenic AhNCED1 plants subjected to PEG stress for 10 h, the expressions of AhNCED1 protein and endogenous ABA content were increased, as well as superoxide level decreased.

Abstract:The sex differences in Humulus scandens were studied by using inter-simple sequence repeat (ISSR) technique. 40 primes from total 62 primers could produce stable bands, and amplified 302 bands. A male-linked fragment with about 553 bp was amplified by I64 primer which was abundant in AT (64.3%). Then the male-linked marker was converted into SCAR marker.

Abstract:The changes in proteome of normal flower and floral reversion buds in longan (Dimocarpus longan Lour.) were studied by using Proteomics method. The results showed that ANS (anthocyanidin synthase) protein was found down-regulated expression in floral reversion buds. ANS cDNA was obtained (GenBank access number: FJ479616) by using RACE method, its full length was 1477 bp, with a 1071 bp open read frame. ANS gene was expressed in E. coli, and a 46 kD heterologous protein was obtained. It suggested that ANS protein play a role in floral reversion in longan.

Abstract:The reflectance characteristics of Hevea brasiliensis leaves were analyzed by using spectral curve and transform features. The results showed that the positions of blue edge, red edge and yellow edge were appeared at near 525 nm, 725 nm and 550 nm, respectively. The correlation between the reflectance spectral data and nitrogen content in rubber leaves was significant within the sensitive waveband (700~1300 nm), which correlation coefficient was the highest (r=0.8422) at the most sensitive waveband (730 nm). The linear regression between the reflectance spectral data and the nitrogen contents was established with the multiple correlation coefficient (R2) at 0.7094.

Abstract:The plant regeneration in vitro was studied using epicotyl segments of Citrus grandis Osbeck ‘Pingshanyou’ as explants. The results showed that the optimum explants were the upper segments of epicotyl, the optimum medium for adventitious shoots induction was MS+6-BA 1.0 mg L-1+TDZ 0.05 mg L-1+NAA 0.2 mg L-1+GA3 1.0 mg L-1+ sucrose 40 g L-1, the induction rate was 100% and the average adventitious shoots reached 8.35 after cultured for 4 weeks. The optimum medium for rooting was 1/2MS+NAA 1.5 mg L-1, the rooting and the average roots were 88.7% and 6.4, respectively. The plantlet survival was 90% after transplanted for 30 days.

Abstract:The phytoactivity of toal alkaloids from stem of Cyperus iria to Oryza sativa, Nicotiana tabacum, Plantago asiatica, Eclipta prostrate, Leptochloa chinensis and antifungal activity against Magnaporthe grisea, Sclerotinia sclerotiovum, Alternaria solani, Fusarium graminearum, Dothiorella gregaria and Physalospora piricola were measured. The results showed that 250~4 000 μg mL-1 total alkaloids had not significant influence in seed germination of O. sativa, but significantly inhibited in seedling height of L. chinensis. Seed germination of N. tabacum, E. prostrate and P. asiatica, seedling height of N. tabacum, seedling fresh weight of O. sativa, N. tabacum and E. prostrate were significantly inhibited treated with 4 000 μg mL-1 total alkaloids. The total alkaloids of low concentrations significantly inhibited in seed germination of L. chinensis, seedling fresh weight of L. chinensis and P. asiatica, seedling root length and height of five species except of seedling height of N. tabacum. However, 25~400 μg mL-1 total alkaloids had no significant inhibition to the growth of F. graminearum, but had to the growth of P. piricola, and 100~400 μg mL-1 total alkaloids had significant inhibition to M. grisea, S. sclerotiovum and A. solani, while did 200~400 μg mL-1 total alkaloids to D. gregariaat, the growth of six fungi were significantly inhibited treated with 400 μg mL-1 total alkaloids, the inhibitory rates were 8.20%, 74.87%, 40.93%, 60.91%, 52.70% and 16.28%, respectively.

Abstract:Forty-five volatile constituents extracted from fresh flowers of five cultivars of Prunus mume, such as ‘Sanlun yudie’, ‘Beijing yudie’, ‘Danbaiyu’, ‘Danfen’ and ‘Jiangnan zhusha’, were identified by headspace solid-phase microextraction (SPME) with a DVB-CAR-PDMS 50/30 µm fiber and gas chromatography-mass spectrometry (GC-MS). The results showed that aromatic compounds were dominated in volatile constituents. The kind and content of compounds caused difference in flower fragrances of cultivars, but some important compounds, such as namely n-hexyl acetate, eugenol, benzyl acetate and α-pinene were common in all cultivars, which was the reason that the fragrance in all cultivars were similar.

Abstract:The effects of storage conditions on pollen germination of Casuarina cunninghamiana Miq. in vitro were studied. The results showed that the optimum concentrations of sucrose and boric acid on pollen germination of C. cunninghamiana Miq. were 15% and 250 mg kg-1, respectively. The solid medium supplemented with agar was beneficial to pollen germination. Pollen at low temperature could maintain germination ability for long time.

Abstract:A male sterile line of resynthsizing Brassica napus was discovered in the interspecific crossing between Brassica napus and B. rapa. The fertility segregation in brother-sister mating (BSM) lines and the hybrids F1, F2 lines from male sterile lines and B. napus cultivars were studied, which showed that the male sterile materialswere double recessive genic male sterile. Using self-crossing and test crossing of different lines in fertility segregated lines, 7 homozygous fertile lines (B1~B7) were screened out, and two genotypes (Ms1Ms1ms2ms2 and ms1ms1Ms2Ms2) were identified. These male sterile materials would play an important role in heterosis utilization and male sterile gene mapping.

Abstract:Granier’s sap flow system is a precise, sensitive and continuous thermal-electric measurement based on heat balance principle. However, any problem in the installation, measurement and maintenance could have direct impact on the data accuracy and reliability. Basing on many years’ experiential field work, in this paper, we introduce the principle and composition of the Granier’s sap flow measurement system, and focus on discussing the most common problems encountered in the installation and maintenance, hence to assist other users to apply the Granier’s sap flow system successfully.

Abstract:The advances in systematics of adaptively radiated Eleusine (Poaceae), involving inflorescence typology, comparative morphology, cytogenetics, molecular phylogeny, were overviewed. Systematic position for Eleusine as a member of subtribe Eleusininae has been verified based on molecular phylogenic analysis, the common characters of Eleusine included three subtypes of inflorescences, seven forms of genome, tetraploids originated from hybridization between diploids, C4 grasses adapted to the mosaic climatic region of semi-arid and semi-humid in east Africa. Based on reliable fossil record and currently geographic distribution, it suggest that Eleusine has originated in east Africa during the late Miocene, and radiated during the Pliocene-Pleistocene interval. The integrating investigation of molecular phylogeny, cytogenetics, paleogeology, paleoclimate data could provide evidence for polyploid orgin and lineage diversification of Eleusine.