波动和静止水文情势下小叶章(Calamagrostis angustifolia)的生理生态特征

通过野外调查与控制试验相结合的方法,比较研究了波动和静止两种水文情势下,沼泽化草甸植物——小叶章(Calamagrostis angustifolia)某些生理生态特征(种群密度与高度、叶长、叶宽、茎长、节长以及叶绿素含量)对不同水分条件的响应。结果表明,不同水文情势对小叶章生理生态特征具有明显的影响。波动水文情势下,小叶章种群、形态指标及叶绿素含量总体随水分的增加而减小或下降,但是由于特定水文情势下形成的群落竞争格局的影响,小叶章单优群落分布带上小叶章各指标值明显大于其它水分带;静止水文情势下,小叶章各指标值呈波动变化,30 cm积水处理下的种群密度、高度、叶宽和茎长以及叶绿素含量与其它处理差别显著。波动水文情势下小叶章各指标测定值均大于静止水文情势下的,同一生活史阶段要较静止水文情势下的提前,生长能力较强。湿地水分条件不仅直接影响植物特性,还通过影响植物定植的土壤环境特征及群落内的竞争格局间接作用于植物。不同水分条件下,小叶章的生理生态特征是水分条件直接与间接作用的综合结果。

拟南芥转录共激活子ANGUSTIFOLIA3(AN3)调控花的雄蕊的形成

雄蕊是种子植物产生花粉的重要生殖器官,其是否正常发育关乎到植物的繁殖状况,并且会对农作物的产量造成影响。通过RT-PCR技术鉴定拟南芥转录共激活子ANGUSTIFOLIA3(AN3)的两个敲除突变体an3-1和an3-4;通过形态学检测发现,突变体an3-1和突变体an3-4的雄蕊较野生型雄蕊短,而雌蕊却无明显变化;通过构建AN3启动子GUS表达载体,对Pro-AN3-GUS植株的花组织进行染色,并观察,结果表明,AN3基因在拟南芥的种子胚、成熟的花粉、柱头、花瓣中均有表达。这个结果证明AN3能在拟南芥生殖生长期间在花器官等重要组织中表达,这个结果与an3-1和an3-4的雄蕊变短的结论一致。由此,我们得出结论:拟南芥转录共激活子AN3正向调控花的雄蕊的形成。

沙枣(Elaeagnus angustifolia)和孩儿拳头(Grewia．biloba G．Don var．parviflora)幼苗气体交换特征与保护酶对干旱胁迫的响应

以沙枣和孩儿拳头2年生盆栽苗为材料,采用称重控水的方法设置4个土壤含水量梯度(CK、T1、T2、T3),研究不同干旱胁迫对沙枣和孩儿拳头气体交换特征与保护酶的影响。结果显示:(1)干旱胁迫不仅引起两物种净光合速率、蒸腾速率、气孔导度、胞间CO2浓度的下降,而且使其日变化曲线在一定程度上发生改变;在轻度(T1)和中度胁迫(T2)下,两物种净光合速率下降主要是由气孔因素引起的,重度胁迫(T3)下,净光合速率下降主要是非气孔因素引起的。(2)随着干旱胁迫增加,沙枣瞬时水分利用效率呈现增加-下降-再增加趋势,孩儿拳头呈现下降趋势;两物种表观光能利用效率显著下降,重度胁迫下(T3),下降率达50%左右,孩儿拳头表观光能利用效率对干旱胁迫比较敏感;两物种表观CO2利用效率总体呈现下降趋势,沙枣表观CO2利用效率日进程经历了单峰(T1)、双峰(T2)、单峰(T3)的变化,孩儿拳头各处理的表观CO2利用效率日变化均呈现单峰曲线。(3)随着干旱胁迫加剧,两物种叶片的超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性先升高后降低,土壤含水量高于12.8%时,两物种SOD酶活性均高于CK,随着土壤含水量的降低,SOD酶活性低于CK;重度胁迫下(T3),沙枣POD酶活性虽然有所下降,但仍高于CK,而孩儿拳头则和CK无显著差异;两物种CAT酶活性在重度胁迫下(T3)显著低于CK;随着干旱胁迫程度的增加,两物种叶片中的丙二醛(MDA)含量均呈现升高趋势,孩儿拳头脂质过氧化程度受干旱胁迫的影响较大。

沙枣(Elaeagnus angustifolia L.)研究现状与展望

沙枣(Elaeagnus angustifolia L.)是胡颓子科胡颓子属的一种小乔木,是一种集生态效益与经济效益于一体的资源植物,是西北地区具有开发利用前景的重要资源。对我国上世纪60年代至今对沙枣的研究文献作一综述,包括沙枣果实、花、叶、果核及树液的成分、木材的理化性质、沙枣的生理生态学特性、引种实验、繁殖方法、品种划分等方面的工作。最后提出了沙枣利用中存在的问题及建议。

Nitrogen cycling of atmosphere-plant-soft system in the typical Calamagrostis angustifolia wetland in the Sanjiang Plain,Northeast China

The nitrogen （N） distribution and cycling of atmosphere-plant-soil system in the typical meadow Calamagrostis angustifolia wetland （TMCW） and marsh meadow Calamagrostis angustifolia wetland （MMCW） in the Sanjiang plain were studied by a compartment model. The results showed that the N wet deposition amount was 0.757 gN/（m^2·a）, and total inorganic N （TIN） was the main body （0.640 gN/（m^2·a））. The ammonia volatilization amounts of TMCW and MMCW soils in growing season were 0.635 and 0.687 gN/m^2, and the denitrification gaseous lost amounts were 0.617 and 0.405 gN/m^2, respectively. In plant subsystem, the N was mainly stored in root and litter. Soil organic N was the main N storage of the two plant-soil systems and the proportions of it were 93.98% and 92.16%, respectively. The calculation results of N turnovers among compartments of TMCW and MMCW showed that the uptake amounts of root were 23.02 and 28.18 gN/（m^2·a） and the values of aboveground were 11.31 and 6.08 gN/（m^2·a）, the re-translocation amounts from aboveground to root were 5.96 and 2.70 gN/（m^2·a）, the translocation amounts from aboveground living body to litter were 5.35 and 3.38 gN/（m^2·a）, the translocation amounts from litter to soil were larger than 1.55 and 3.01 gN/（m^2·a）, the translocation amounts from root to soil were 14.90 and 13.17 gN/（m^2·a）, and the soil （0-15 cm） N net mineralization amounts were 1.94 and 0.55 gN/（m^2·a）, respectively. The study of N balance indicated that the two plant-soil systems might be situated in the status of lacking N, and the status might induce the degradation of C. angustifolia wetland.

Plant Diversity Performance After Natural Restoration in Reclaimed Deyeuxia angustifolia Wetland

Deyeuxia angustifolia wetlands were widely distributed in the Sanjiang Plain in Northeast China. Due to strong demand for food production, large-area wetlands were reclaimed to farmlands, which threatened regional ecological security greatly. Since the 21 th century, returning farmlands to wetlands was widely adopted for natural restoration in the Sangjiang Plain. As the first reflection of wetland restoration, vegetation succession of restored D. angustifolia wetlands should be fully assessed. In this study, vegetation investigation was carried out in three restored D. angustifolia wetlands with 5, 8 and 12 yr restoration, respectively. Meanwhile, a natural D. angustifolia wetland was selected as reference wetland. Results showed that community composition changed greatly and there was visible community succession. Community dominant species changed from composite to gramineae as restoration time increasing.At first, weeds community appeared in the restored wetlands, especially the xerophytes developed to the pioneer species rapidly. And then, mesophytes and wetland species became the dominant species in the restored wetlands. Finally, wetland species, especially D. angustifolia, occupied the dominant position of restored community. Shannon-wiener index(H) and Simpson index(D) both decreased to close to natural D. angustifolia wetlands. Compared with natural D. angustifolia wetland, species composition and diversity in restored wetlands were more complex and higher. As restoration time increasing, there were not significant differences between community characteristics of restored wetlands and natural wetland. All these suggested that vegetation in reclaimed D. angustifolia wetland could be restored naturally, but its restored period is 10 yr at least. From another angle, it is important to protect current natural wetlands.

Sulfur cycle in the typical meadow Calamagrostis angustifolia wetland ecosystem in the Sanjiang Plain,Northeast China

The sulfur cycle and its compartmental distribution within an atmosphere-plant-soil system was studied using a compartment model in the typical meadow Calamagrostis angustifolia wetland in the Sanjiang Plain Northeast China. The results showed that in the typical meadow C. angustifolia wetland ecosystem, soil was the main storage compartment and current hinge of sulfur in which 98.4% sulfur was accumulated, while only 1.6% sulfur was accumulated in the plant compartment. In the plant subsystem, roots and litters were the main storage compartment of sulfur and they remained 83.5% of the total plant sulfur. The calculations of sulfur turnover through the compartments of the typical meadow C. angustifolia wetland ecosystem demonstrated that the above-ground component took up 0.99 gS/m^2 from the root, of which 0.16 gS/m^2 was translocated to the roots and 0.83 gS/m^2 to the litter. The roots took in 1.05 gS/m^2 from the soil, subsequent translocation back to the soil accounted for 1.31 gS/m^2, while there was 1.84 gS/m^2 in the litter and the net transfer of sulfur to the soil was more than 0.44 gS/（m^2·a）. The emission of H2S from the typical meadow C. angustifolia wetland ecosystem to the atmosphere was 1.83 mgS/（m^2·a）, while carbonyl sulfide （COS） was absorbed by the typical meadow C. angustifolia wetland ecosystem from the atmosphere at the rate of 1.76 mgS/（m^2·a）. The input of sulfur by the rainfall to the ecosystem was 4.85 mgS/m^2 during the growing season. The difference between input and output was 4.78 mgS/m^2, which indicated that sulfur was accumulated in the ecosystem and may cause wetland acidify in the future.

Extraction, Identification and Antioxidative Properties of the Flavonoid-Rich Fractions from Leaves and Flowers of Cassia <i>angustifolia</i>

Flavonoids identification, total flavonoids content and antioxidant activity of the extracts from the leaves as well as flowers of Cassia angustifolia were determined. Five different extraction techniques were used for the extraction of flavonoids from leaves and flowers. Total flavonoid contents (TFC) in the extracts were determined by UV-visible spectrophotometry. Individual flavonoids were identified and quantified by high-performance liquid chromatography coupled with photodiode array detection and electrospray ioniza- tion tandem mass spectrometry (HPLC-PDA-ESI-MS). It has been examined that aqueous ethanol (70%) fractions of C. angustifolia flowers and leaves are highly rich in flavonoids and microwave extraction is the best method for the extraction of individual flavanoid constituents (1 - 9) as well as total flavonoid contents. It was also found that compound 8 was absent in the leaves and compounds 2 and 5 could not be identified. The extracts of C. angustifolia flowers and leaves show strong antioxidant activity.

Two New Sequiterpenoids from Helicteres angustifolia

A new sesquiterpenoid lactone, 3,6,9-trimethyl-pyrano[2,3,4-de]chromen-2-one (1) and a novel sesquiterpenoid quinone, 6-[2-(5-acetyl-2,7-dimethyl-8-oxo-bicyclo[4.2.0]octa-1,3,5- trien-7-yl)-2-oxo-ethyl]-3,9-dimethylnaphtho[1,8-bc]pyran-7,8-dione (2) together with a known perezone (3) were isolated from the roots of Helicteres angustifolia. The structures were elucidated as mainly on the basis of 1D and 2D NMR spectroscopic data.

Curcuma angustifolia ameliorates carbon tetrachloride-induced hepatotoxicity in HepG2 cells and Swiss albino rats

Objective:To determine the antioxidant and hepatoprotective potential of methanol extract of rhizome of Curcuma angustifolia(MECA)against carbon tetrachloride(CCl4)-induced hepatic damage in vitro and in vivo.Methods:DPPH,ABTS and reducing power assays were performed to estimate the antioxidant effect of MECA.In vitro cytotoxicity of MECA against HepG2 cells was evaluated,whereas serum biochemical parameters and levels of antioxidative enzymes were measured in vivo and in vitro.Additionally,histopathological studies were estimated in order to investigate the hepatoprotective efficacy of MECA.Furthermore,GC-MS analysis of the extract was performed to identify the chemical components.Results:MECA exhibited strong antioxidant activity and attenuated CCl4-induced decrease in the viability of HepG2 cells.Additionally,MECA significantly restored the ALT,AST,ALP,TP and albumin level in comparison with the CCl4 group.After pre-treatment with MECA,effects of SOD,CAT and GSH were increased as well as lipid peroxidation amount decreased on CCl4-induced hepatotoxicity in in vitro and in vivo model.Furthermore,histopathological observation confirmed that MECA reduced liver injury induced by CCl4 in rats.GC-MS analysis confirmed the presence of bioactive constituents such as α-tocopherol(12.27%),phytol(7.61%),squalene(3.71%),β-sitosterol(2.19%),eugenol(2.59%),curcumenol(1.20%),β-elemene(1.00%)and eucalyptol(0.89%).Conclusions:MECA contains antioxidant and hepatoprotective constituents such asα-tocopherol,phytol,squalene and eugenol and exerts hepatoprotective effect both in vitro and in vivo.

沙枣（Elaeagnus angustifolia L．）在黄河三角洲盐碱地的应用前景

黄河三角洲是我国三大三角洲之一，总面积达5．4×105 hm2，其中盐碱地面积达70％以上，并且仍在以每年1．3×105 hm2的速度增加．黄河三角洲地区土地盐碱化程度高，夏季降雨集中，春秋季较干旱，这些不利的环境因素导致该地区生态环境比较脆弱，绿化造林难度大，植被覆盖面积小，当地的景观生态系统比较单一．因此，筛选优质抗盐碱树种并建立一套完整的绿化栽培体系，以提高黄河三角洲地区的绿化面积是现在所面临的严峻问题．沙枣由于抗旱耐盐碱成为改良黄河三角洲地区的绿化树种，本文综述了沙枣作为黄河三角洲地区盐碱地绿化树种的应用前景．

A new flavonoid glucoside from Cassia angustifolia

A new flavonoid glucoside with a known one was isolated from the leaves of Cassia angustifolia. Based on the spectral analysis, including MS, ^1H NMR, ^13C NMR, DEPT, ^1H-1HCOSY, HMQC, HMBC and NOSEY, their chemical structures were determined as kaempferol-3-O-[（6＇＇＇-O-trans-sinnapoyt）-β-D-glucopyranosyl （1 → 6）]-β-D-glucopyranoside 1 and apigenin-6,8-di-C-glycoside 2.

Comparative studies on leaf epidermal micromorphology and mesophyll structure of Elaeagnus angustifolia L.in two different regions of desert habitat

In order to obtain qualitative and quantitative characteristics of leaf epidermal micromorphology and mesophyll structure to evaluate the responses ofElaeagnus angustifolia L. to different environmental factors, epidermal micromorphology was observed by scanning electron microscopy （SEM）, and mesophyll structure was studied by light microscopy （LM） and transmission electron microscopy （TEM）. Materials were selected from Linze County, Gansu Province （material A） and Qitai County, Xinjiang Uygur Autonomous Region （material B） of China. Results show that lamina thickness was higher in material A, with one layer of epidermal cells in both adaxial and abaxial surfaces, and epidermal cell radial length was significantly longer in the adaxial surface. E. angustifolia leaves are typically bifacial, with a higher ratio of palisade to spongy tissue in material A. The thickness of trichome layer of epidermis was thicker in material A. In contrast, cell wall and cuticular wax of the epidermal cells were thinner in material A than in material B. Chloroplast ultrastructure was different with the approximate spherical chloroplast containing numerous starch grains and osmiophilic granules in ma- terial A, while only the spindly chloroplast contained starch grains in material B. Multiple layers of peltate or stel- late-peltate trichomes occupied both leaf surfaces in material A and the abaxial surface in material B, while the adaxial surface of material B contained few trichomes. Stomata were not observed on the leaf surfaces in materials A and B by SEM because of trichome obstruction. Our results indicate that the leaf structure of E. angustifolia is closely correlated with environmental factors, and the combination of leaf epidermal micromorphology and mesophyll structure afford re- sistance to environmental stress.

Studies on the Antibacterial Activity of the Extract of Stachysarpheta angustifolia

Objective:To investigate the scientific bases for the traditional use of stachytarpheta angustigolia.MEthods:In vitro antibacterial activity of the aqueous and ethanol extract of the plant was investigated using the agar cup plate diffustion method.Results:The ethanol extract of the plant showed antibacterial activity against Escherichia coli,Streptococcus faecalis,Shigella dysenteriae,Staphylococcus aureus(S.aureus),Salmonella sp., pseudomonas aeruginosa and Neisseria gonorthoseae,while the water extract was active against Escherichia coli,Streptococcus faecalis,Shigella dysenteriae,Staphylococcus aureus and Pseudomonas aeruginasa.The ethanol extract exhibited higher antibacterial activity than the water extract,The minimum inhibitory comcentration(MIC) and minimum bactericidal concentration(MBC) of the ethanol extract were0.65g/L and 0.85g/L,respectively.against S.aureus.Treatment of the extract at higher temperature,60℃ increased the sensitivity of the test of ganisms to the plant extract.Phytochemical analysis indicated that the plant possesses tannins,saponins as well as phenols.Concluslon:A scientific basis that the plant possesses antibacterial activity and it could be a probable source of therapeutic agent.

沙枣(Elaeagnus angustifolia L.)的大、小孢子发生和雌雄配子发生

小孢子形成为同时型,小孢子在一个四分体中的排列为辐射(两侧)对称。药壁由表皮、药室内壁、中层和绒毡层所组成;成熟时仅由表皮和纤维层所组成;药壁的特点为中层一层和腺质(分泌)绒毡层。花粉粒为三角形和具三孔沟的,释放时为2细胞。大孢子的孢原为1—2个细胞,直接起大孢子母细胞功能。胞质分裂横向,大胞子排列是“直线型”,四分体中合点端大孢子为功能大孢子单核胚囊经过三次有丝分裂形成成熟胚囊(雌配子体)。沙枣的胚囊为蓼型(1卵器,3反足细胞和一个2核的中央细胞)。

Extraction and Structure Investigation of the Poly-saccharides from the Pollen of Typha Angustifolia L.

Three polysaccharides, TAA, TAB, TAC have been isolated from the pollen of Typha angustifolia L. , and purified by hot water extraction, alcohol precipitation, Sevage method, gel filtration (Sephadex G50) and ion-exchange chromatography on DEAE Sephadex A25 and DEAE-cellulose. Their purities were tested by gel filtration and electrophoresis. Their structures were characterized by paper chromatography of the hydrolysis products, GLC analysis of the alditol acetates, alkylation analysis, 1H NMR and 13C NMR spectra. TAA is mainly composed of a-L-arabinofuanose, β-D-galactose and α-D-galacturonic acid, while the backbones of TAB and TAC are composed of (1→5)-linked α- L-arabinofuranosyl residues.

The eff ect of Rhizophagus irregularis on salt stress tolerance of Elaeagnus angustifolia roots

We assessed the eff ects of arbuscular mycorrhizal fungi(AMF)Rhizophagus irregularis inoculation on salt stress tolerance in roots of the drought-tolerant plant Elaeagnus angustifolia.We studied a plant growth index,spore density and hyphal length density of AMF,the Na+contents and ultrastructure of root cells,as well as rhizosphere soil enzyme activities of mycorrhizal and non-mycorrhizal E.angustifolia seedlings under diff erent salt stress.Under salt stress,growth of E.angustifolia with mycorrhizal inoculation was higher than that of non-inoculated treatments.The spore density and hyphal length density decreased signifi cantly under salt stress in rhizosphere soil of mycorrhizal E.angustifolia seedlings(p<0.05).The root cells of E.angustifolia seedlings inoculated with R.irregularis at 300 mmol L−1 salt had more organelles,greater integrity,and lower root Na+contents than those of non-inoculated seedlings.In addition,the results showed notably higher activities of catalase,phosphatase,urease and saccharase in rhizosphere soil of the mycorrhizal seedlings in response to salinity compared to those of the non-mycorrhizal seedlings.Therefore,AMF inoculation could enhance salt stress tolerance in roots of E.angustifolia.

Bousmekines A-E,New Alkaloids from Two Bousigonia Species:B.angustifolia and B.mekongensis

Four new monoterpenoid indole alkaloids,bousmekines A-D(1-4),and one new pyranopyridine alkaloid,bousmekine E(5),were isolated from the twigs and leaves of Bousigonia angustifolia and Bousigonia mekongensis.Their structures including absolute configurations were elucidated by a combination of MS,NMR,ECD calculation,and single-crystal X-ray diffraction analysis.Compound 2 was an eburnea-type MIAs characterized by a rare chlorine atom while 5 possessed a novel pyranopyridine moiety.Their cytotoxicities against several human cancer cell lines were evaluated and compound 1 exhibited significant cytotoxicity with IC50 values of 0.8-7.4μM.

Phytoextraction of Metal Contaminants by Typha Angustifolia: Interaction of Lead and Cadmium in Soil-Water Microcosms

A greenhouse study was conducted on phytoextraction and accumulation of lead (Pb) and cadmium (Cd) from contaminated soil – water microcosms by the narrow-leaved cattail, Typha angustifolia. The plants were grown in sandy loam soil containing 1,666 and 38.5 mg/L of Pb(NO3)2 and Cd(NO3)2 respectively. The trends of lead and cadmium by T. angustifolia for all soil – water microcosms suggested interaction effects as decreased soil lead concentrations and increased water cadmium concentrations over time. T. angustifolia expressed trends as increased biomass in all contaminated shoots and roots examined. Cadmium uptake in shoot and root biomass slightly decreased when lead was initially added to the soil but cadmium uptake in root biomass increased after 30 days. Data suggested an interaction between lead and cadmium and possible that lead uptake was inhibited when cadmium was present.