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1.
Embryonal-suspensor masses from immature embryos from cones of Sitka spruce (Picea sitchensis (Bong.) Carr.) proliferated on a modified Murashige & Skoog medium with N6-benzyl-aminopurine, kinetin, 2,4-dichlorophenoxyacetic acid and an organic nitrogen source. The slimy white embryonal-suspensor masses with proembryos were maintained on a solid proliferation medium with reduced amounts of growth regulators. Transfer of embryonal-suspensor masses to a non-woven polyester carrier with liquid maturation media containing ±2-cis-4-trans-abscisic acid and a reduced amount of inositol and organic nitrogen resulted in synchronized embryo formation. Further development was achieved on a medium without ±2-cis-4-trans-abscisic acid and organic nitrogen. Somatic embryos were successfully transferred ex vitrum.Abbreviations ABA ±2-cis-4-trans-abscisic acid - BAP N6-benzyl-aminopurine - ESM embryonal-suspensor masses - KIN kinetin - 2,4-D 2,4-dichlorophenoxyacetic acid  相似文献   

2.
Shoot multiplication of hornbeam was stimulated onWPM, QL andDKW medium supplemented with a low concentration of BAP or BPA (0.1-0.2 mg I -1) andIBA (0.1 mg I -1). Low concentration of thidiazuron promoted axillary bud formation, higher concentration inhibited shoot elongation. Microshoots were rooted onWPM supplemented with a low auxin concentration (IBA or NAA 0.2-0.5 mg I -1). High rooting percentages were obtained. Shoot proliferation of ash was stimulated on MS andDKW medium supplemented withBAP orBPA (2.0-5.0 mg I -1) andIBA (0.1 mg I -1). Root formation was promoted onWPM containing a low auxin concentration. Rooted plantlets were transplanted into soil and after hardening off the micropropagated trees were planted in the field. The planted trees grew normally without showing signs of abnormality.  相似文献   

3.
There are several factors thought to assist invasive weeds in colonization of ecosystems. One of these factors is allelopathy, the negative effect of chemicals produced by one plant on neighboring plants, frequently mediated through root exudates and other plant leachates. Acroptilon repens (Asteraceae) is one of the most invasive and ecologically threatening weed species in western North America. A bioassay-guided fractionation of the root extracts of this plant led to the isolation of five polyacetylenic compounds, of which one [5′-methoxy-1′-(5-prop-1-yn-1-yl-2-thienyl)-hexa-2′,4′-diyin-6′-yl acetate] was hitherto unknown. The structures of these compounds were elucidated on the basis of spectroscopic analysis (IR, ESIMS, 1H, 13C NMR and 2D NMR). All of the compounds obtained, except 1-chloro-4-(5-penta-1,3-diyn-1-yl-2-thienyl)but-3-yn-2-ol, showed phytotoxic activity against Arabidopsis thaliana seedlings. The presence of 4′-chloro-1′-(5-penta-1,3-diyn-1-yl-2-thienyl)-but-2′-yn-3′-ol was detected in the root exudates of aeroponically grown A. repens plants. None of the polyacetylenes isolated in this study were found in Colorado soils collected between September 2006 and July 2007 in an A. repens colonized site. However, polyacetylene 5 in A. repens infested soil from Washington was found in June, 2007. Contrary to our previous report, the compound 7,8-benzoflavone (6) was not detected in root exudates, nor was it encountered in extracts of roots, aerial parts or infested soil. Since we could not repeat this work, the original report has been retracted [Stermitz, F.R., Bais, H.P., Foderaro, T.A., Vivanco, J.M., 2003. 7,8-Benzoflavone: a phytotoxin from root exudates of invasive Russian knapweed [A retraction]. Phytochemistry 64, 493-497.].  相似文献   

4.
Alriksson  A.  Olsson  M. T. 《Plant and Soil》1995,(1):103-110
The aim of this study was to test the hypothesis that afforestation changes the content and distribution of soil organic carbon, nutrients and pH in the A-horizon of land previously used in agriculture, and that such soil changes depend on stand development. The investigation was evaluated as a completely randomised design with three treatments representing different age classes of trees: 20 years (Y20), 40 years (Y40) and 55 years (Y55). Eighteen trial plots, six per treatment, were established in plantations of Picea abies (L.) Karst. on soils of similar texture and mineralogy. Tree volume was 220 m3 ha-1 in Y20, 400 in Y40 and 440 m3 ha-1 in Y55.Concentrations of carbon (C) and nitrogen (N) were significantly higher in the uppermost part of the soil in the older stands Y40 and Y55 than in Y20. The total amount of organic C in the litter layer plus the top 15 cm of the soil differed between age classes, with Y40 and Y55 having the largest amounts. A reference layer (15–20 cm) was used in calculating the amount of soil C that had accumulated in the horizon since afforestation, being about 10 tonnes ha-1 of C in Y20 and 19 tonnes ha-1 in Y40 and Y55.Cation exchange capacity (CEC) and base saturation (BS) was higher in the older stands. Carbon contents and CEC were strongly correlated. In Y40 and Y55, pH was significantly lower than in Y20 in the lower part of the soil horizon. There was a general decrease with depth of C, N, CEC, K+ and Mg2+ in the soil horizon. BS, Ca2+, Na+ and pH showed a somewhat different pattern of distribution, with deceasing values in the upper part of the soil horizon and increasing values in the lower part of the soil horizon.Abbreviations BD Bulk density - CEC cation exchange capacity - BS base saturation - Ca2+ calcium ion - Mg2+ magnesium ion - K+ potassium ion - Na+ sodium ion - C carbon - Ca a accumulated carbon content - C t total carbon content - N nitrogen - Y20 age class 20 years - Y40 age class 40 years - Y55 age class 55 years  相似文献   

5.
Rhizome buds, excised from threeCurcuma spp., and ginger, inoculated aseptically on MS medium with varying levels of BAP and kinetin, produced multiple shoots. For shoot multiplication, a concentration of 3.0 mg/l BAP was found to be optimum for all the species.In vitro plants were successfully established in the field and were morphologically uniform. A simple method to extend the subculture interval was used and its relevance to germplasm conservation is discussed.Abbreviations BAP 6-benzylaminopurine - kinetin 6-furfurylaminopurine - MS Murashige and Skoog (1962)  相似文献   

6.
H. Urlaub  G. Jankowski 《Planta》1982,155(2):154-161
Cell homogenates from Catharanthus roseus (L.) G. Don. grown S-autotrophically on sulfate in the dark are capable of reducing adenylysulfate (APS) to cysteine. This reduction required a particulate protein fraction from the cell extract and reduced ferredoxin as the electron donor. The protein fraction (MW 700,000±50,000) was found to contain Fd:NADP+ reductase, glutathione reductase and an unspecific dithiol reductase, and APS-sulfotransferase and thiosulfonate reductase activity. Resolution into these individual enzyme activities led to a non-restorable loss of the APS reducing activity. It was observed that a slow gradual decay of the APS reducing activity was accompanied by a likewise slow generation of a ferredoxin-dependent sulfite reductase.Enzymes and abbreviations APS Adenosine 5-phosphosulfate - APS-kinase E.C.2.7.1.25 - ATP-sulfurylase E.C.2.7.7.4 - Fd ferredoxin - Fd-NADP+-reductase E.C.1.6.7.1. - Glutathione reductase E.C.1.6.4.2. - G6P Glucose 6-phosphate - G6PDH glucose 6-phosphate dehydrogenase, E.C.1.1.49 - GSSG oxidized glutathione - GSSO3H S-sulfoglutathione - MVH reduced methylviologen - OASS O-acetylserine sulfhydrylase-E.C. 4.2.99.8 - Sulfite reductase E.C.1.8.1.2  相似文献   

7.
Cowpea (Vigna unguiculata (L.) Walp.) nodules have been investigated by means of cytochemical and immunocytochemical procedures at the ultrastructural level in order to assess the role of the uninfected cells in ureide biogenesis. Uricase activity in the nodules was shown by cytochemical methods to be localized exclusively in the numberous large peroxisomes confined to the uninfected cells; the small peroxisomes in the infected cells did not stain for uricase. Uricase was also localized in the peroxisomes of uninfected cells by immunogold techniques employing polyclonal antibodies against nodule-specific uricase of soybean. There was no labeling above background of any structures in the infected cells. The results indicate that the uninfected cells are essential for ureide biogenesis in cowpea. Although tubular endoplasmic reticulum, the presumptive site of allantoinase, increases greatly in the uninfected cells during nodule development, it virtually disappears as the nodules mature. The inconsistency between the disappearance of the tubular endoplasmic reticulum from older nodules and the high allantoinase activity reported for older plants remains to be explained.Abbreviations DAB 3,3-diaminobenzidine - ER endoplasmic reticulum - GARG goat anti-rabbit immunoglobulin G - IgG immunoglobulin G - kDa knodalton - Mr apparent molecular mass - SDS-PAGE sodium dodecyl sulfate-polyacrylamide gel electrophoresis  相似文献   

8.
A new iridoid, 5β,6β-dihydroxyantirrhide (1) was isolated from the dried leaves of Pseuderanthemum carruthersii (Seem.) Guill. var. atropurpureum (Bull.) Fosb. (Acanthaceae), together with 13 known compounds, including two iridoids, linarioside and antirrhinoside; five phenylethanoids, echipuroside A, verbascoside, isoverbascoside, isomartynoside and osmanthuside B; and six flavonoids, luteolin 7-O-β-d-glucopyranoside, luteolin 7-O-rutinoside, apigenin 7-O-rutinoside, apigenin 6-C-α-l-arabinopyranosyl–8-C-β-l-arabinopyranoside, apigenin 6,8-di-C-α-l-arabinopyranoside and apigenin 6-C-β-d-xylopyranosyl–8-C-α-l-arabinopyranoside. Their chemical structures were elucidated by 1D and 2D NMR as well as HR-ESI-MS spectroscopic analysis. Some purified compounds were evaluated the acetylcholinesterase inhibition and cytotoxic activities against the HeLa cervical cancer cell line and the MCF-7 breast cancer cell line at the concentration of 100 μg/mL. Luteolin 7-O-β-d-glucopyranoside exhibited cytotoxic activities against both the HeLa cervical cancer cell line and the MCF-7 breast cancer cell line. Verbascoside and isoverbascoside showed strong cytotoxic activity against the MCF-7 breast cancer cell line. The tested compounds showed the AChE inhibitory activity fairly weak.  相似文献   

9.
The need for conservation of biotic diversity is well recognized. However, improved techniques for the efficient, cost effective-preservation of plant germplasm are needed. The conservation and distribution of plant germplasm in vitro is gaining acceptance. However, increased usage is dependent upon the ability of curators to minimize culture maintenance requirements. This report examines the effect of various levels of sucrose, photoperiod, temperature, sorbitol and mannitol on minimal growth storage of Ipomoea batatas (L.) Lam. Growth was reduced 50% with a temperature reduction of from 21.1 to 15.6°C. Sucrose concentrations of 15 and 20 g l-1 resulted in reduced plant stature with few adverse effects on plantlet viability or morphology. Reduction of photoperiod from 16 to 4 h produced smaller, slightly chlorotic, but otherwise normal plants. The addition of sorbitol or mannitol to culture media generally produced undesirable effects on gross plant morphology and loss of apical dominance. Genotype x growth retarding treatment interactions were observed for all variables examined.Abbreviations PL plant introduction - f.w. fresh weight - SE standard error  相似文献   

10.
Redroot pigweed is one of the injurious agricultural weeds on a worldwide basis. Understanding of its interference impact in crop field will provide useful information for weed control programs. The effects of redroot pigweed on cotton at densities of 0, 0.125, 0.25, 0.5, 1, 2, 4, and 8 plants m-1 of row were evaluated in field experiments conducted in 2013 and 2014 at Institute of Cotton Research, CAAS in China. Redroot pigweed remained taller and thicker than cotton and heavily shaded cotton throughout the growing season. Both cotton height and stem diameter reduced with increasing redroot pigweed density. Moreover, the interference of redroot pigweed resulted in a delay in cotton maturity especially at the densities of 1 to 8 weed plants m-1 of row, and cotton boll weight and seed numbers per boll were reduced. The relationship between redroot pigweed density and seed cotton yield was described by the hyperbolic decay regression model, which estimated that a density of 0.20–0.33 weed plant m-1 of row would result in a 50% seed cotton yield loss from the maximum yield. Redroot pigweed seed production per plant or per square meter was indicated by logarithmic response. At a density of 1 plant m-1 of cotton row, redroot pigweed produced about 626,000 seeds m-2. Intraspecific competition resulted in density-dependent effects on weed biomass per plant, a range of 430–2,250 g dry weight by harvest. Redroot pigweed biomass ha-1 tended to increase with increasing weed density as indicated by a logarithmic response. Fiber quality was not significantly influenced by weed density when analyzed over two years; however, the fiber length uniformity and micronaire were adversely affected at density of 1 weed plant m-1 of row in 2014. The adverse impact of redroot pigweed on cotton growth and development identified in this study has indicated the need of effective redroot pigweed management.  相似文献   

11.
Summary The potential of somatic embryogenesis was evaluated for 10 cultivars of sweet potato through extensive embryogenic response and isozyme analysis. Embryogenic callus was induced by incubating lateral buds on Murashige and Skoog medium containing 10 M 2,4-dichlorophenoxyacetic acid for 6–8 weeks. The frequency of embryogenic response was low, and varied with genotypes, ranging from 0 to 17%. Embryo to plantlet formation could be enhanced by the use of the combination of 2,4-dichlorophenoxyacetic acid with kinetin, both used at 0.01 M. Embryogenic callus with its potential of plantlet formation has constantly been maintained for over two years. However, after several subcultures, 0.5 to 12% of embryogenic callus reverted irreversibly into friable fast-growing non-embryogenic callus whose ability to regenerate shoots was then definitively lost. The isozymes of esterase, peroxidase, glutamate oxaloacetate transaminase and acid phosphatase investigated in this study were found appropriate to distinguish compact embryogenic from friable non-embryogenic callus in sweet potato. In fact, the callus reversion was associated with a loss of bands or a decline in isozyme activity. On the contrary, very small changes in isozyme activity or no specific changes at all were observed during the differentiation of embryogenic callus into globular embryos.Abbreviations Acp acid phosphatase - BAP 6-benzylaminopurine - cv cultivar - df degree of freedom - 2,4-D 2,4-dichlorophenoxyacetic acid - Est esterase - Got glutamate oxaloacetate transaminase - IAA indole-3-acetic acid - MS Murashige and Skoog (1962) medium - Prx peroxidase - Tris tris(hydroxymethyl)aminomethane  相似文献   

12.
Association mapping is a powerful high-resolution mapping tool for complex traits. The objective of this study was to identify QTLs for partial resistance to Phytophthora sojae. In this study, we evaluated a total of 214 soybean accessions by the hypocotyl inoculation method, and 175 were susceptible. The 175 susceptible accessions were then evaluated for P. sojae partial resistance using slant board assays. The 175 accessions were screened with 138 SSR markers that generated 730 SSR alleles. A subset of 495 SSR loci with minor allele frequency (MAF) ≥ 0.05 was used for association mapping by the Tassel general linear model (GLM) and mixed linear model (MLM) program. This soybean population could be divided into two subpopulations and no or weak relatedness was detected between pairwise accessions. Four SSR alleles, Satt634-133, Satt634-149, Sat_222-168 and Satt301-190, associated with partial resistance to P. sojae were detected by both GLM and MLM methods. Of these identified markers, one marker, Satt301, was located in regions where P. sojae resistance QTL have been previously mapped using linkage analysis. The identified markers will help to understand the genetic basis of partial resistance, and facilitate future marker-assistant selection aimed to improve resistance to P. sojae and reduce disease-related mortality in soybean.  相似文献   

13.
By means of gas chromatography-selected ion monitoring-mass spectrometry using an isotope-dilution assay with 4,5,6,7-tetradeutero-indole-3-acetic acid as the internal standard, indole-3-acetic acid has been estimated to be present in aseptically cultured gametophytes of wild-type Physcomitrella patens (Hedw.) B.S.G. at a level of 0.075 g g–1 dry weight or 2.1 ng g–1 fresh weight.Abbreviations IAA indole-3-acetic acid - d4IAA 4,5,6,7-tetra-deutero-indole-3-acetic acid - [14C]IAA indole-3-[2-14C]-acetic acid - GC-SIM-MS gas chromatography-selected ion monitoring-mass spectrometry  相似文献   

14.
Embryonal-suspensor mass lines (ESM lines) from mature embryos of three open-pollinated families of Norway spruce [Picea abies (L.) Karst.] were stabilized on several culture media varying in nutrient composition. A pattern of relationship between parameters of polyembryogenic culture performance and medium composition was genetically determined. Stabilized ESM lines could be classified into two phenovariants: (i) lines of homogenous ESM composed entirely of somatic proembryos, and (ii) lines of heterogeneous ESM composed of a mixture of nonembryogenic callus and aggregates of somatic proembryos. The formation of one or the other phenovariant was independent of genotype, but strongly determined by the medium composition.Abbreviations ABA abscisic acid - BA 6-benzyladenine - ESM embryonal-suspensor mass - N nitrogen - NAA -naphthyl-1-acetic acid  相似文献   

15.
Rhamphichthys rostratus (L.) emits brief pulses (2 ms) repeated very regularly at 50 Hz. The electric organ shows a heterogeneous distribution of the electrocyte tubes and the occurrence of three electrocyte types (caudally innervated, rostrally innervated and marginallycaudally innervated). In the sub-opercular region the electric organ consists of a pair of tubes containing only caudally innervated electrocytes. At the abdominal region the EO consists of three pairs of tubes. Each pair contains one of the described electrocyte types. The number of electrocyte tubes increases toward the tail to reach nine or ten pairs in the most caudal segments. In the intermediate region most tubes contain doubly innervated electrocytes except the ventral pair that contains caudally innervated electrocytes. The caudal 25% contains exclusively caudally innervated electrocytes. The electric organ discharge consists of five wave components (V1 to V5). Electrophysiological data are consistent with the hypothesis that V1 results from the activity of the rostral faces of rostrally innervated electrocytes. V2 results from the activities of rostral faces of marginally-caudally innervated electrocytes while V3 results from the activities of caudal faces of most electrocytes. Curarization experiments demonstrated that V4 and V5 result from action potential invasion and are not directly elicited by neural activity.Abbreviations AEN1 anterior electromotor nerve 1 - AEN2 anterior electromotor nerve 2 - BMB boraxic methylene blue - CIE caudally innervated electrocytes - EMF electromotive force - EO electric organ - EOD electric organ discharge - I current amplitude - MCIE marginally-caudally innervated electrocytes - MT medial tubes - PEN posterior electromotor nerve - R n internal impedance - RIE rostrally innervated electrocytes - Rl load resistor - SAT short abdominal tubes - V voltage amplitude  相似文献   

16.
Four cycloartane- (hareftosides A–D) and oleanane-type triterpenoids (hareftoside E) were isolated from Astragalus hareftae along with fifteen known compounds. Structures of the compounds were established as 3,6-di-O-β-d-xylopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane (1), 3,6,24-tri-O-β-d-xylopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane (2), 3-O-β-d-xylopyranosyl-3β,6α,16β,25-tetrahydroxy-20(R),25(S)-epoxycycloartane (3), 16-O-β-d-glucopyranosyl-3β,6α,16β,25-tetrahydroxy-20(R),24(S)-epoxycycloartane (4), 3-O-[β-d-xylopyranosyl-(1→2)-O-β-d-glucopyranosyl-(1→2)-O-β-d-glucuronopyranosyl]-soyasapogenol B (5) by the extensive use of 1D- and 2D-NMR experiments along with ESI-MS and HR-MS analyses.  相似文献   

17.
Callus production from willow (Salix viminalis L.) protoplasts   总被引:2,自引:0,他引:2  
Protoplasts were isolated from cell suspensions of Salix viminalis (basket willow) clone 78-0-90 and S. schwerinii clone 77-0-77, using cellulysin and macerase in modified Woody Plant medium. For clone 78-0-90, 6.3 · 106 ± 1.9 · 106 protoplasts were obtained per gram fresh weight. Cell divisions started two days after protoplast isolation and gave rise to callus which has been maintained in culture for up to four years. Protoplast yield from the clone 77-0-77 was lower (less than 106 protoplasts per gram cells), cell division was infrequent and no callus was obtained. Protoplasts were also isolated from the leaves of willow shoot cultures using cellulysin and pectolyase, but these did not show cell divisions.Abbreviations BA benzyladenine - 2,4-D 2,4-dichlorophenoxyacetic acid - MS medium Murashige & Skoog (1962) medium - WP medium Woody Plant medium (Lloyd & McCown 1981)  相似文献   

18.
European Journal of Wildlife Research - Durch Vergleich von 145 Wolfsschädeln mit 165 Schädeln großer Hunde fand der Verfasser sieben Merkmale am Schädel und ein Merkmal am...  相似文献   

19.
L. Beerhues  H. Robenek  R. Wiermann 《Planta》1988,173(4):532-543
The two chalcone-synthase forms from leaves ofSpinacia oleracea L. were purified to apparent homogeneity. Antibodies were raised against both proteins in rabbits. The specificity of the antibodies was tested using immunotitration, immunoblotting, and immunoelectrophoresis techniques. The antibodies exhibited exclusive specificity for chalcone synthase and did not discriminate between the two antigens. The homodimeric chalcone synthases had the same subunit molecular weight but differed in their apparent native molecular weights. The peptide maps indicated extensive homology between the proteins. Chalcone-synthase activity was not detected in isolated spinach chloroplasts. Both enzyme forms were present in spinach cell-suspension cultures in which they were induced by light.Abbreviations DEAE diethylaminoethyl - DTE 1,4-dithioerythritol - EDTA ethylenediaminetetraacetic acid - HPLC high-performance liquid chromatography - IgG immunoglobulin G - SDS-PAGE sodium dodecyl sulfate-polyacrylamide gel electrophoresis Parts of the results were presented at the 14th International Botanical Congress at Berlin in July 1987  相似文献   

20.
 Pyrethrum (Tanacetum cinerariifolium (Trevir.) Schultz-Bip.) produces environmentally benign pesticides, the pyrethrins, and tansy (Tanacetum vulgare L.) lower terpenes of variable biological effectiveness. As an approach to improve the oil content and composition of tansy for enhanced biological activity, a somatic hybridization technique between tansy and pyrethrum was established. About 1×106 of leaf-mesophyll protoplasts of both species were mixed and fused with a solution containing 15% polyethylene glycol. Light-green and yellowish calli developed from the fusion experiments. The fusion-derived calli grew vigorously on MS medium supplemented with 6.4 mg l-1 of BAP, 0.8 mg l-1 of NAA, and 30–40 g l-1 of glucose. Nuclear DNA content, RAPD patterns, and volatile compounds were analyzed to determine the hybridity of the calli. The nuclear DNA content of the tansy and pyrethrum genotypes, and the protoplast-derived calli of tansy were 6.41, 7.39, 13.84, and 8.11 pg, respectively. The nuclear DNA content of individual calli derived from the protoplast fusion between tansy +tansy ranged from 8.84 (F43A) to 19.59 pg (F43C) while those of the tansy+pyrethrum fusions were 10.66 (F46A) and 31.87 pg (F46B). Using four 10-mer primers a total of 56 RAPD-PCR fragments were produced. The distance matrices of fragments were calculated by average linkage cluster analysis. Two visually separated clusters were observed. One cluster consisted of the two tansy genotypes and the fusion-derived callus F43A; the other consisted of pyrethrum and fusion-derived calli F46B and F46C. Volatile compounds, such as decadienal, artedouglasia oxide, heptadecane, syringaldehyde and coniferyl alcohol, analyzed by gas chromatography mass spectrometry, were found only in the protoplast fusion-derived calli F43A and F46B. Several less volatile compounds were also detected only in fusion calli. Hexadecanoic and linoleic acids were common to fusion-derived calli and tansy, and one unknown compound to fusion-derived calli and pyrethrum. Pyrethrins I and II were detected from pyrethrum, but not from the fusion-derived calli. The additive nuclear DNA content of protoplast fusion-derived calli and the results of the RAPDs suggest that interspecific fusions had occurred. The small number of volatile compounds detected from both the fusion calli and from the donor species indicates that the unorganized callus tissue is unable to produce tissue-specific volatile compounds. Received: 4 August 1998 / Accepted: 30 September 1998  相似文献   

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