Influence of ethanolic extract of Tephrosia purpurea Linn. on mast cells and erythrocytes membrane integrity

The ethanolic extract of T. purpurea Linn. was studied for its in vitro effect on rat mast cell degranulation and erythrocyte membrane integrity in vitro. The extract in concentration of 25-200 microg/ml showed a dose-dependant inhibition of rat mast cell degranulation induded by compound 48/80 and egg albumin. T. purpurea extract was found to inhibit haemolysis of erythrocytes induced by hypotonic solution but accelerated haemolysis induced by heat at a concentration of 100 microg/ml. The studies reveal that the ethanolic extract of T. purpurea may inhibit degranulation of mast cells by a mechanism other than membrane stabilization.     

美洲冬青的组织培养与快速繁殖

1植物名称美洲冬青[Ilex verticillata (Linn.) A.Gray],由美国缅因大学张冬林博士提供。2材料类别带腋芽的嫩茎段。3培养条件启动培养基:(1)MS 6-BA0.5mg·L-1(单位下同) IBA0.1。增殖与壮苗培养基:(2)MS 6-BA1.0 NAA0.5;(3)MS KT1.0 NAA0.5;     

Water Stress in Sunflower (Helianthus annuus L.) 2. Effects on Leaf Cells and Leaf Area

Three water stress treatments were applied at early, mid andlate stages of vegetative development in sunflower. The effectsof these stresses on leaf area, cell frequency, number of cellsper leaf and palisade cell area were examined. Final leaf area was reduced in all stress treatments. The largestreduction occurred in leaves that were unfolding or about tounfold at the commencement of stress. At full expansion of theseleaves cell frequency had increased, cell number had decreasedand cell area had decreased. These results help to explain theeffects of stress on final leaf area, especially the reducedarea of the lower leaves that are most sensitive to water stress. Helianthus annuus L., sunflower, water stress, node number, leaf area     

Bioactivity of alkamides isolated from Echinacea purpurea (L.) Moench.

Alkamides from the roots of Echinacea purpurea (L.) Moench were examined for anti-inflammatory activity in an in vitro model system. Cyclooxygenase-I (COX-I) and cyclooxygenase-II (COX-II) inhibitory activities were assessed at pH 7 for alkamides isolated from E. purpurea roots to compare inhibitory activities between the two cyclooxygenase isozymes. At 100 microg/ml, several E. purpurea alkamides inhibited COX-I and COX-II enzymes in the range of 36-60% and 15-46%, respectively, as compared to controls. Mosquitocidal activity was assessed at 100 and 10 microg/ml, with 100% mortality against Aedes aegyptii L. larvae noted for several E. purpurea alkamides at 100 microg/ml.     

驱虫斑鸠菊的组织培养与快速繁殖

1 植物名称驱虫斑鸠菊[Vernonia anthelmintica (Linn.)Willd.],别名:印度山茴香. 2 材料类别果实. 3 培养条件以MS为基本培养基.芽诱导培养基为:(1)1/2MS;继代增殖培养基为:(2)MS+BA1.0 mg·L-1+NAA 0.2:(3)MS+BA 1.0+NAA 0.5:(4)MS+6-BA 1.0+NAA 1.0;生根培养基为:(5)MS+NAA 0.1;(6)1/2MS+NAA 0.5.     

Distribution of Endophytic Bacteria in Alopecurus aequalis Sobol and Oxalis corniculata L. from Soils Contaminated by Polycyclic Aromatic Hydrocarbons

The distributions of endophytic bacteria in Alopecurus aequalis Sobol and Oxalis corniculata L. grown in soils contaminated with different levels of polycyclic aromatic hydrocarbons (PAHs) were investigated with polymerase chain reaction followed by denaturing gradient gel electrophoresis technology (PCR-DGGE) and cultivation methods. Twelve types of PAHs, at concentrations varying from 0.16 to 180 mg·kg⁻¹, were observed in the roots and shoots of the two plants. The total PAH concentrations in Alopecurus aequalis Sobol obtained from three different PAH-contaminated stations were 184, 197, and 304 mg·kg⁻¹, and the total PAH concentrations in Oxalis corniculata L. were 251, 346, and 600 mg·kg⁻¹, respectively. The PCR-DGGE results showed that the endophytic bacterial communities in the roots and shoots of the two plants were quite different, although most bacteria belonged to Firmicutes, Proteobacteria, Actinobacteria and Bacteroidetes. A total of 68 endophytic bacterial strains were isolated from different tissues of the two plants and classified into three phyla: Firmicutes, Proteobacteria and Bacteroidetes. In both plants, Bacillus spp. and Pseudomonas spp. were the dominant cultivable populations. With an increase in the PAH pollution level, the diversity and distribution of endophytic bacteria in the two plants changed correspondingly, and the number of cultivable endophytic bacterial strains decreased rapidly. Testing of the isolated endophytic bacteria for tolerance to each type of PAH showed that most isolates could grow well on Luria-Bertani media in the presence of different PAHs, and some isolates were able to grow rapidly on a mineral salt medium with a single PAH as the sole carbon and energy source, indicating that these strains may have the potential to degrade PAHs in plants. This research provides the first insight into the characteristics of endophytic bacterial populations under different PAH pollution levels and provides a species resource for the isolation of PAH-degrading endophytic bacteria.     

红果腺肋花楸的组织培养及快速繁殖

1植物名称红果腺肋花楸[Aronia arbutifolia(Linn.)Pers.‘Brilliantissima’],由美国缅因州大学张冬林博士提供。2材料类别带腋芽的嫩茎段。     

Water Stress and Leaf Growth of Field Beans (Vicia faba L.) in the Field: Leaf Number and Total Leaf Area

The leaf area growth of field beans grown under covers in thefield was measured non-destructively on plants subjected tothree different degrees of soil water stress by means of dryingcycles of different lengths in 1974 and 1975. After a periodof 46 days the total leaf area of the well-watered plants wasabout double that of the non-watered ones. The total leaf areaat the final-sampling and the mean plant water potential duringthe observation period were linearly related with highly significantcorrelation coefficients (0·96 in 1974 and 0·86in 1975). The differences between treatments in total leaf areawere mainly produced by the mechanisms determining leaf sizerather than those associated with leaf production and maintenance,namely leaf production, unfolding and death. In neither yearwas leaf production or unfolding sensitive to water stress beforeflowering. Plant water potential () exerted a cumulative longterm effect on these two mechanisms. The threshold values of for reducing the rates of leaf production and unfolding weremore negative in the drier year (1975). Leaf death was affectedby drought earlier than leaf production and unfolding. Vicia faba, field bean, water stress, leaf area     

香樟、枸树主茎水分传导能力分布研究

本文从植物生长发育的机理发出,从理论推导出植物主茎传导能力与主茎长度、导管长度的关系式,导管越长,榈传导能力越大,香樟主茎长度大于１８ｃｍ、枸树大于１２ｃｍ时,传导能力随样品长度线笥变化;较知时,传导能力随样品长度的缩短迅速增加,出现短路现象。试验测定了香樟、枸树主茎水分长距离运输的传导能力分布,结果与理论预示的安全一致,表明理论分析是正确可靠的,这一规律具有普遍意义。     

Rates of Leaf Initiation and Leaf Growth in Agropyron repens (L.) Beauv.

Rates of leaf initiation, emergence, and growth have been measuredduring the period between the production of one and of ten matureleaves on the primary shoot of Agropyron repens. There is aprogressive decline in the growth rate of successively formedleaves so that at the time of formation of the next leaf primordiumeach primordium is smaller than its predecessor at a comparablestage of development. There is also a trend towards a diauxicpattern of growth with a lag phase apparently coinciding withthe transition from apical to intercalary growth of the youngleaf. Up to the six-leaf stage the rate of leaf formation exceedsthe rate of emergence and leaf primordia accumulate on the shootapex. Thereafter the rate of emergence exceeds the rate of formation.These changes in rates of leaf formation and growth are interpretedin terms of competition for assimilates between expanding leavesand leaf primordia, and between the primary and axillary shootapices.     

海芋的组织培养与快速繁殖

1植物名称海芋[Alocasia macrorrhiza（Linn．）Schott]。 2材料类别块茎上的不定芽。 3培养条件（1）无菌外植体培养基：MS;（2）诱导愈伤组织培养基：MS＋6-BA1．0mg．L^-1（单位下同）＋NAA0．1;（3）丛生芽诱导及增殖培养基：MS＋6-BA3．0＋NAA0．1＋椰乳100;（4）壮苗及生根培养基：1／2MS＋NAA0．1。     

Molecular Specificity of Haustorial Induction in Agalinis purpurea (L.) Raf. (Scrophulariaceae)

An exogenous signal normally contained in host root exudateis required for initiation of the haustorium by the root parasiteAgalinis purpurea (L.) Raf. (Scrophulariaceae). Two flavonoidsthat induce haustoria have been isolated from gum tragacanthand a number of structural analogues have been synthesized.The results show that a high degree of molecular specificityis required for haustorial induction. Both isolated flavonoidscontain substituted 3-methoxyphenol functionality, and syntheticanalogues have shown that 4-substituted 3-methoxyphenol functionalityis critical for high levels of haustorial induction. These dataprovide a model for understanding host recognition at the levelof haustorial induction in parasitic angiosperms. Agalinis purpurea (L.) Raf. Scrophulariaceae, haustorial induction, flavonoids, molecular specificity, parasitic angiosperms, xenognosin     

Leaf Growth in Cotton (Gossypium hirsutum L.) 1. Growth in Area of Main-stem and Sympodial Leaves

A model is presented for growth of individual and successivemain-stem leaves of cotton, based on a series of indoor experimentsand data sets from the literature. Three variable parametersare used to describe individual leaf growth: relative growthrate of meristematic tissue (R¹), relative rate of approachof final area (R₂) and a ‘position parameter’ (t_0.5)which governs the transition from meristematic to extensiongrowth. Final area of a leaf does not occur in the model asa deterministic quantity but it is a result of the processesduring growth. The model generates successive mainstem leavesand sympodial leaves as an integrated system. Assimilate shortagesoccurring in the plant operate on R₁ leading to the characteristicchange of final leaf area along the mainstem. Gossypium hirsutumL., cotton, leaf growth, relative growth rate, meristematic tissue, extension growth, mathematical model     

重瓣棣棠花的组织培养和快速繁殖

1植物名称重瓣棣棠花[Kerria japonica（Linn．）DC．f．plenifloya（Witte）Rehd]。 2材料类别幼嫩茎段。     

鸦胆子的组织培养与快速繁殖

1植物名称鸦胆子[Brucea javanica（L．）Merr．]。 2材料类别带节茎段。     

Effects of acid irrigation and liming on nitrate reduction and nitrate content of Picea abies (L.) Karst. and Oxalis acetosella L.

Nitrate reductase activities (NRA) and nitrate concentration per unit biomass in Picea abies (L.) Karst. roots from four different soil horizons and in leaves and roots of the frequent field-layer species Oxalis acetosella L. were measured on six different irrigation and liming treatments within the Höglwald project, S-Bavaria, Germany. Liming increased and acid irrigation reduced soil nitrate availability when compared to control plots. Nitrate assimilation capacities of the respective plant compartments per unit of soil volume or ground area were calculated from the NRA per unit of biomass and from the biomass distribution on the various treatments.Mean NRA per unit of biomass in Picea abies roots ranged between 0.23 and 0.09 mol NO ₂ ^- g_-1 d.w. h_-1 without significant effects of soil horizon or treatment. Limed and non-limed treatments showed for Picea different root distributions within the soil profile, but root biomass per unit of ground area (295 to 220 g d.w. m^-2) was not affected by the various treatments. Thus, nitrate assimilation capacity of Picea roots per unit of ground area ranged between 19.5 and 11.4 mol NO ₂ ^- m^-2 h_-1 without major treatment effects.In laminae of Oxalis acetosella mean NRA per unit of biomass ranged between 2.91 and 0.27 mol NO ₂ ^- g_-1 d.w. h_-1 and, in contrast to Picea abies, treatment effects were found with NRA on limed plots increased and on acid irrigated plots reduced when compared to control plots. Mean leaf biomass of Oxalis per unit of ground area ranged between 9.57 and 0.66 g d.w. m^-2 and responded in a similar manner to the various treatments. Thus, for the Oxalis leaf NRA per unit of ground area (27.85 to 0.18 mol NO₂ m^-2 h_-1) a cumulative response to the variations in nitrate availability was found.The different responses of Picea abies and Oxalis acetosella to changes in soil nitrate availability are discussed with respect to their suitability to prevent soil nitrate leaching.