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1.
Identification of Endogenous Gibberellins in Dormant Bulbils of Chinese Yam, Dioscorea opposita
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It is known that dormancy of the genus Dioscorea is induced by application of gibberellin (GA) A3. To understand the role of GAs in dormancy induction, endogenous GAs have been identified by Kovats retention indices and full mass spectra from capillary gas chromatography-mass spectrometry analysis of purified extract from dormant bulbils of Dioscorea opposita Thunb. These include GA4, GA9, GA12, GA19, GA20, GA24, GA36, and GA53; their presence suggests the occurrence of two biosynthetic pathways in D. opposita bulbils, the early 13-hydroxylation pathway and the non-13-hydroxylation pathway. 相似文献
2.
Identification of Ten Gibberellins from Sporophytes of the Tree fern, Cyathea australis 总被引:2,自引:1,他引:1
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Yamane H Yamaguchi I Kobayashi M Takahashi M Sato Y Takahashi N Iwatsuki K Phinney BO Spray CR Gaskin P Macmillan J 《Plant physiology》1985,78(4):899-903
Ten gibberellins (GAs) have been identified by Kovats retention indices and full mass spectra from GC-MS analysis of purified extracts of sporophytes of the tree-fern, Cyathea australis. These include the known GA1, GA4, GA9, GA15, GA24, GA35, and GA58 and three new GAs, 12β-hydroxyGA9 (GA69), 12α-hydroxyGA9 (GA70) and 12β-hydroxyGA4 (GA71). The structure of GA71 was established by the preparation and characterization of its methyl ester (as a metabolite of GA4 methyl ester in a culture of prothallia of Lygodium japonicum). 相似文献
3.
《Bioscience, biotechnology, and biochemistry》2013,77(11):1953-1954
Eight gibberellins (GAs) were identified in extracts of buds of Aralia cordata by full scan GC/MS and by Kovats retention indices. These GAs comprised five GAs on the early-13-hydroxylation pathway [GA1, GA19, GA20, GA44, and GA53] and three other GAs [GA4, GA15, and GA37]. The major GAs were GA19 and GA44. 相似文献
4.
The endogenous gibberellins (GAs) in leaf tissues of two day-neutral cultivars (Rapella and Selva) of strawberry (Fragaria × ananassa Duch.) were analysed using combined gas chromatography -- mass spectrometry (GC-MS). Seven of the later members of the 13-hydroxylation GA biosynthetic pathway were identified, by comparison of Kovats retention indices and mass spectral data obtained for methyl ester trimethylsilyl ether derivatives, either with data obtained from authentic compounds or literature values. GA1, GA3, GA8, GA17, GA19, GA20 and GA29 were detected in extracts of both cultivars. 相似文献
5.
Dormancy in Peach (Prunus persica L.) Flower Buds : I. Floral Morphogenesis and Endogenous Gibberellins at the End of the Dormancy Period
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Luna V Lorenzo E Reinoso H Tordable MC Abdala G Pharis RP Bottini R 《Plant physiology》1990,93(1):20-25
Flower buds of peach (Prunus persica L.) trees, cv Novedad de Cordoba (Argentina), were collected near the end of the dormant period and immediately before anthesis. After removal of scale leaves, morphological observations of representative buds, made on transverse and longitudinal microtome sections, showed that all verticils making up the flower are present in an undifferentiated form during the dormant period (June). Flower buds collected at the end of dormant period (August) showed additional growth and differentiation, at which time formation of two ovules was beginning in the unicarpelar gynoecium. Dehiscence of anthers had not yet occurred 10 days before full bloom, and the ovules were still developing. Free endogenous gibberellin (GA)-like substances were quantified by bioassay (Tan-ginbozu dwarf rice microdrop) after SiO2 partition column chromatography, reversed phase C18-high performance liquid chromatography, and finally Nucleosil [N(CH3)2]high performance liquid chromatography. Bioactive fractions were then subjected to capillary gas chromatography-mass spectrometry-selected ion monitoring (GC-MS-SIM). Gibberellins A1, A3, and A8 were tentatively identified in peach flower buds using GC-SIM and Kovat's retention indices, and relative amounts approximated by GC-SIM (2:8:6 for GA1, GA3, and GA8, respectively). The highest concentration (330 nanograms per gram dry weight) of free GA1/GA3 was found in dormant buds (June) and diminished thereafter. The concentration free of GA1/GA3 did not increase immediately prior to bud break. However, high GA1/GA3 concentrations occurred during stages where rate of growth and cellular differentiation of (mainly fertile) verticils can be influenced. 相似文献
6.
The gibberellin (GA) content of E-1, a tall genotype of early flowering lettuce (Lactuca sativa L.), and of three selected GA-responsive dwarfs, dwf1, dwf2, and dwf21, has been determined using 13C-labeled internal standards and gas chromatographymass spectrometry (GC-MS). In the shoots of the E-1 parent, GA1, 3-epi-GA1, GA3, GA5, GA8, GA19, GA20, GA29, and GA53 were identified by full scan GC-MS and Kovats retention indices. Purification by immunoaffinity chromatography selective for 13-hydroxy GAs, was necessary for GA identification. Relative to the parent E-1, the concentrations of GA1, GA8, GA20, and GA29 in the shoots of dwf2 plants were reduced to about 10% and in shoots of dwf21 plants to less than 50%. In dwf1 the levels of GA1, GA8, and GA29 were also reduced to less than 50% of the parent E-1, but the level of GA20 was fivefold higher than in E-1. Plant height was correlated with the endogenous levels of GA1 and GA8. 相似文献
7.
Implication of Gibberellins in Head Smut (Sporisorium reilianum) of Sorghum bicolor 总被引:1,自引:1,他引:0
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The head smut fungus, Sporisorium reilianum ([Kuhn] Landon and Fullerton), was shown to reduce plant height in infected Sorghum bicolor ([L.] Moench) plants. The major reductions occurred in the internodes nearest the panicle and were more severe in naturally infected than in inoculated plants. Less affected plants developed reproductively sterile panicles, and eventually smutted panicles developed phyllodied growths which progressed into leafy shoots. Extracts of smutted, sterile, and healthy (control) panicles of field-grown plants exhibited gibberellin (GA)-like activity in the dwarf rice bioassay. When extracts were purified and assayed with deuterium-labeled GA standards by gas chromatography-mass spectrometry-selected ion monitoring (GC-MS-SIM), GA1, GA3, GA19, GA20, and GA53 were detected based on coelution with the standards, identical Kovats retention index values, and matching ion masses and relative abundances for three major ions. In addition, based on published Kovats retention index values, ion masses, and relative abundance values, GA4, GA7, GA8, GA14, GA29, and GA44 were tentatively identified. Quantitative analysis revealed that panicles of healthy control plants contained from 60 to 100% higher total concentrations of GAs than panicles of smutted plants. These comparisons were most striking for the early 13-hydroxylation pathway precursors GA53, GA44, and GA19 but not for GA20. Extracts of S. reilianum sporidia and culture medium exhibited GA-like bioactivity, and GA1 and GA3 were detected based on GC-MS-SIM assay with 2H-labeled internal standards. Quantitative analysis of these GAs showed increasing concentrations from 4 to 7 to 10 days of culture and a decline at 20 days. This is the first GC-MS-SIM detection of GAs in a non-Ascomycete fungus, and the disease symptoms and quantitative data suggested that fungal infection may interfere with biosynthesis of GAs by the host plant. 相似文献
8.
I. F. Kappers W. Jordi F. M. Maas L. H. W. van der Plas 《Journal of Plant Growth Regulation》1997,16(4):219-225
In alstroemeria (Alstroemeria hybrida), leaf senescence is retarded effectively by the application of gibberellins (GAs). To study the role of endogenous GAs in
leaf senescence, the GA content was analyzed by combined gas chromatography and mass spectrometry. Five 13-hydroxy GAs (GA19, GA20, GA1, GA8, and GA29) and three non-13-hydroxy GAs (GA9 and GA4) were identified in leaf extracts by comparing Kováts retention indices (KRIs) and full scan mass sprectra with those of
reference GAs. In addition, GA15, GA44, GA24, and GA34 were tentatively identified by comparing selected ion monitoring results and KRIs with those of reference GAs. A number of
GAs were detected in conjugated form as well. Concentrations of GAs in alstroemeria changed with the development of leaves.
The proportion of biologically active GA1 and GA4 decreased with progressive senescence and the fraction of conjugated GAs increased.
Received May 26, 1997; accepted August 12, 1997 相似文献
9.
Endogenous Gibberellins from Sporophytes of Two Tree Ferns, Cibotium glaucum and Dicksonia antarctica 总被引:2,自引:1,他引:1
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Yamane H Fujioka S Spray CR Phinney BO Macmillan J Gaskin P Takahashi N 《Plant physiology》1988,86(3):857-862
Gibberellin A1 (GA1), 3-epi-GA1, GA4, GA9, 11α-hydroxyGA12, 12α-hydroxyGA12, GA15, GA17, GA19, GA20, GA25, GA37, GA40, GA58, GA69, GA70, and GA71 have been identified from Kovats retention indices and full scan mass spectra by capillary GC-MS analyses of purified extracts from sporophytes of the tree fern, Cibotium glaucum. Abscisic acid, dihydrophaseic acid, an epimer of 4′-dihydrophaseic acid, and the epimeric ent-6α, 7α, 16α, 17-(OH)4 and ent-6α, 7α, 16β, 17-(OH)4 derivatives of ent16, 17-dihydrokaurenoic acid, in addition to the epimeric 16α, 17- and 16β, 17-dihydroxy-16, 17-dihydro derivatives of GA12, were also identified in extracts of C. glaucum. An oxodihydrophaseic acid and a hydroxydihydrophaseic acid were also detected. In extracts of sporophytes of Dicksonia antarctica, GA4, GA9, 12α- and 12β-hydroxyGA12, GA15, GA25, and GA37 were identified by the same criteria, as well as abscisic acid, phaseic acid, 8′-hydroxymethylabscisic acid and dihydrophaseic acid. This is the first time that GA40 has been identified in a higher plant; it is also the first report of the natural occurrence of the two gibberellins, 11α- and 12β-hydroxyGA12. The total gibberellin (GA) content in C. glaucum (tall) was at least one order of magnitude greater than that of D. antarctica (dwarf) based on total ion current response in GC-MS and bioassay data. Abscisic acid was a major component of D. antarctica and the oxodihydrophaseic acid was a major component of C. glaucum. 相似文献
10.
《Bioscience, biotechnology, and biochemistry》2013,77(9):1500-1502
In the xylem exudate extracted from the current-year stems of apple (Malus domestica Borkh.), gibberellins A15, A17, A18, A19, A23, A44, and A53 were identified, and 16,17-dihydro-17-hydroxy GA19 was presumed from full-scan mass spectra and Kovats retention indices. 相似文献
11.
Identification of Gibberellins A(1), A(5), A(29), and A(32) from Immature Seeds of Apricot (Prunus armeniaca L.) 总被引:1,自引:1,他引:0
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Gibberellins (GAs) A1, A5, and A29 were identified, and also GA32 was confirmed, as endogenous GAs of immature seeds (3-4 weeks after anthesis, 0.25-0.5 gram fresh weight) of apricot (Prunus armeniaca L.) based on capillary gas chromatography (GC), retention time (Rt), and selected ion monitoring (SIM), in comparison with authentic standards. Fractions subjected to GC-SIM were purified and separated using sequential solvent partitioning → paper chromatography → reverse phase C18 high performance liquid chromatography (HPLC) → bioassay on dwarf rice cv Tan-ginbozu. Two other peaks of free GA-like bioactivity (microdrop and immersion dwarf rice assays) were eluted from C18 HPLC at Rts where GA4/7 and GA8 (or other GAs with similar structures) would elute. Also, three unidentified GA glucoside-like compounds (based on bioactivity on the immersion assay, and no bioactivity on the microdrop assay) were noted. There were very high amounts of GA32 (112 ng of GA3 equivalents per gram fresh weight), and minor amounts (0.5 ng of GA3 equivalents) for each of GA1 and GA5, respectively, based on the microdrop assay. 相似文献
12.
After the application of 2.36 Curies per millimole [2,3-3H]gibberellin A20 (GA20) to 21-day-old maize (Zea mays L., hybrid CM7 × CM49) plants, etiolated maize seedlings, or maturing maize cobs, a number of 3H-metabolites were observed. The principal acidic (pH 3.0), ethyl acetate-soluble metabolite was identified as [3H]GA1 on the basis of co-chromatography with standard [3H]GA1 on SiO2 partition, high resolution isocratic elution reverse phase C18 high performance liquid chromatography and gas-liquid chromatography radiocounting. Two other acidic metabolites were identified similarly as [3H]GA8 and C/D ring-rearranged [3H]GA20, although gas-liquid chromatography radiocounting was not performed on these metabolites. Numerous acidic, butanol-soluble (e.g. ethyl acetate-insoluble) metabolites were observed with retention times on C18 high performance liquid chromatography radiocounting similar to those of authentic glucosyl conjugates of GA1 and GA8, or with retention times where conjugates of GA20 would be expected to elute. Conversion to [3H]GA1 was greatest (23% of methanol extractable radioactivity) in 21-day-old maize plants. In etiolated maize seedlings, the C/D ring-rearranged [3H]GA20-like metabolite was the major acidic product, while conversion to [3H]GA1 was low. 相似文献
13.
《Bioscience, biotechnology, and biochemistry》2013,77(4):564-566
A new gibberellin (GA) was identified from extracts of cotyledons of 7 day-old canola seedlings (Brassica campestris cv. Tobin). This GA is 12α-hydroxy-GA1 and has been assigned the trivial name of GA85. Isolation was monitored by the Tan-ginbozu dwarf rice micro-drop assay after each high-performance liquid chromatography (HPLC) step. Identification was based on Kovats retention index (KRI) and the mass spectrum of the methyl ester, trimethylsilyl ether (MeTMSi) derivative after analysis by gas chromatography-mass spectrometry (GC-MS) in comparison with an authentic sample of 12α-hydroxy-GA1. Based on quantitation by the dwarf rice micro-drop assay, GA85 is one of the major biologically active GAs in cotyledons of young canola seedlings. 相似文献
14.
E. Jensen S. Eilertsen A. Ernsten O. Juntilla R. Moe 《Journal of Plant Growth Regulation》1996,15(4):167-171
The effect of day/night temperature regimes on stem elongation and on the content of endogenous gibberellins (GAs) in vegetatively propagated plants of Campanula isophylla cv. Hvit have been studied. Compared with a constant temperature regime at 18°C (18/18°C), stem and internode elongation was enhanced significantly by a combination of high day/low night temperature (21/15°C) and inhibited by an opposite regime (15/21°C). Gibberellins A1, A19, A44, A53, and A97 were identified as endogenous components in Campanula. (GA97 was earlier referred to as 2-OH-GA53.) Quantitative analysis of the endogenous GAs indicates that temperature regimes that stimulate elongation growth are accompanied by an increase in the level of GA1, GA19, and GA44. On the other hand, in plants grown under conditions that reduced stem elongation growth, there was an increased level of GA97.Abbreviations DIF
difference between day temperature and night temperature
- GA
gibberellin
- HPLC
high performance liquid chromatography
- GC-MS
gas chromatography-mass chromatography
- SPE
solid phase extraction
- TMS
trimethylsilyl
- MSTFA
N-methyl-N-TMS-trifluoroacetamide
- KRI
Kovats retention index
- SIM
selected ion monitoring
- D2
deuterated 相似文献
15.
Paul Gaskin Michael Hutchison Norman Lewis Jake MacMillan Bernard O. Phinney 《Phytochemistry》1984,23(3):559-564
The metabolism of several ring C and D-functionalized ent-kaur-16-en-19-oic acids by cultures of Gibberella fujikuroi, mutant B1-41a, to the corresponding derivatives of the normal fungal gibberellins (GAs) and ent-kaurenoids is described. A range of 12α- and 12β-hydroxyGAs and ent-kaurenoids are characterized by their mass spectra and GC Kovats retention indices. The mass spectral and GC data are used to identify the 12α-hydroxy derivatives of GA12, GA14, GA37 and GA4 (GA58), and of the 12β-hydroxy derivatives of ent-7α-hydroxy- and ent-6α, 7α-dihydroxykaurenoic acids, in seeds of Cucurbita maxima. Similarly the metabolites of GA9, formed in seeds of Pisum sativum and cultures of G.fujikuroi, mutant B1-41a, are identified as 12α-hydroxyGA9. ent-11β-Hydroxy- and ent-11-oxo-kaurenoic acids are metabolized by the fungus to the corresponding 11-oxygenated derivatives of the normal fungal ent-kaurenoids and some C20-GAs; no 11-oxygenated C19-GAs are formed. Grandiflorenic acid, 11β-hydroxygrandiflorenic acid, attractyligen and ent-15β-hydroxykaurenoic acid are metabolized to unidentified products. 相似文献
16.
Qualitative and Quantitative Analyses of Gibberellins in Vegetative Shoots of Normal, dwarf-1, dwarf-2, dwarf-3, and dwarf-5 Seedlings of Zea mays L 总被引:18,自引:7,他引:11
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Fujioka S Yamane H Spray CR Gaskin P Macmillan J Phinney BO Takahashi N 《Plant physiology》1988,88(4):1367-1372
Gibberellins A12 (GA12), GA53, GA44, GA19, GA17, GA20, GA29, GA1, and GA8 have been identified from extracts of vegetative shoots of normal (wild type) maize using full scan capillary gas chromatography-mass spectrometry and Kovats retention indices. Seven of these gibberellins (GAs) have been quantified by capillary gas chromatography-selected ion monitoring using internal standards of [14C4]GA53, [14C4]GA44, [2H2] GA19, [13C1]GA20, [13C1]GA29, [13C1]GA1, and [13C1]GA8. Quantitative data from extracts of normal, dwarf-1, dwarf-2, dwarf-3, and dwarf-5 seedlings support the operation of the early 13-hydroxylation pathway in vegetative shoots of Zea mays. These data support the positions in the pathway blocked by the mutants, previously assigned by bioassay data and metabolic studies. The GA levels in dwarf-2, dwarf-3, and dwarf-5 were equal to, or less than, 2.0 nanograms per 100 grams fresh weight, showing that these mutants are blocked for steps early in the pathway. In dwarf-1, the level of GA1 was very low (0.23 nanograms per 100 grams fresh weight) and less than 2% of that in normal shoots, while GA20 and GA29 accumulated to levels over 10 times those in normals; these results confirm that the dwarf-1 mutant blocks the conversion of GA20 to GA1. Since the level of GAs beyond the blocked step for each mutant is greater than zero, each mutated gene probably codes for an altered gene product, thus leading to impaired enzyme activities. 相似文献
17.
Identification of Gibberellins in Spinach and Effects of Light and Darkness on their Levels 总被引:17,自引:9,他引:8
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The endogenous gibberellin (GA) content of spinach (Spinacia oleracea) was reinvestigated by combined gas chromatography-mass spectrometry analysis. The 13-hydroxy GAs: GA53, GA44, GA19, GA17, GA20, GA5, GA1, GA29, and GA8; the non-3, 13-hydroxy GAs: GA12, GA15, GA9, and GA51; and the 3β-hydroxy GAs: GA4, GA7, and GA34, were identified in spinach extracts by comparing full-scan mass spectra and Kovats retention indices with those of reference GAs. In addition, spinach plants contained GA7-isolactone, 16,17-dihydro-17-hydroxy-GA53, GA29-catabolite, 3-epi-GA1, and 10 uncharacterized GAs with mass spectra indicative of mono- and dihydroxy-GA12, monohydroxy-GA25, dihydroxy-GA24, and dihydroxy-GAg. The effect of light-dark conditions on the GA levels of the 13-hydroxylation pathway was studied by using labeled internal standards in selected ion monitoring mode. In short day, the GA levels were higher at the end of the light period than at the end of the dark period. Levels of GAs at the end of each short day were relatively constant. During the first supplementary light period of long day treatment, GA53 and GA19 declined dramatically, GA44 and GA1 decreased slightly, and GA20 increased. During the subsequent high-intensity light period, the GA20 level decreased and the levels of GA53, GA44, GA19, and GA1 increased slightly. Within 7 days after the beginning of long day treatment, similar patterns for GA53 and GA19 occurred. Furthermore, when these plants were transferred to darkness, an increase in the levels of GA53 and GA19 was observed. These results are compatible with the idea that in spinach, the flow through the GA biosynthetic pathway is much enhanced during the high-intensity light period, although GA turnover occurs also during the supplementary period of long day, both effects being responsible for the increase of GA20 and GA1 in long day. 相似文献
18.
Tomonobu Toyomasu Hiroko Tsuji Hisakazu Yamane Masayoshi Nakayama Isomaro Yamaguchi Noboru Murofushi Nobutaka Takahashi Yasunori Inoue 《Journal of Plant Growth Regulation》1993,12(2):85-90
Gibberellin A1 (GA1), 3-epi-GA1 GA17, GA19, GA20, and GA77 were identified by Kovats retention indices and full-scan mass spectra from gas chromatography-mass spectrometry analysis of a purified extract of mature seeds of photoblastic lettuce (Lactuca sativa L. cv. Grand Rapids). Non-13-hydroxylated GAs such as GA4 and GA9 were not detected even by highly sensitive radioimmunoassay. These results show that the major biosynthetic pathway of GAs in lettuce seeds is the early-13-hydroxylation pathway leading to GA1, which is suggested to be physiologically active in lettuce seed germination. Quantification of endogenous GAs in the lettuce seeds by gas chromatography-selected ion monitoring using deuterated GAs as internal standards indicated that the endogenous level of GA1 increased to a level about three times that of dark control 6 h after a brief red light irradiation, and that far-red light given after red light suppressed the effect of red light. The contents of GA20 and GA19 were not affected by the red light irradiation. Evidence is also presented that 3-epi-GA1 is a native GA in the lettuce seeds. 相似文献
19.
Tissue-culture-propagated own-rooted cv. Spartan apple trees (Malus domestica Borkh.) planted in 1979 were treated in 1983 and 1985 via a soil-line trunk drench with the plant growth retardant paclobutrazol [(2RS, 3RS)-1-(4-chlorophenyl)-4.4-dimethyl-2-(1,2, 4-triazol-1-yl) pentan-3-ol]. Seeds of immature fruits from untreated and treated trees were sampled in 1989 ca 75 days after full bloom. After seeds were freeze-dried, gibberellins (GAs) were extracted, purified and fractionated via C18 reversed-phase high-performance liquid chromatography (HPLC). Gibberellins A1, A3, A4, A7, A8, A9, A15, A17, A19, A20, A24, A34, A35, A44, A51, A53, A54, A61, A62, A63 and A68 were identified by using C18 HPLC, gas chromatography-selected ion monitoring and Kovats retention indices. Eight of the GAs identified were also quantified by using deuterated internal standards. The paclobutrazol applications caused a 55% reduction of vegetative shoot elongation in 1989, but both treated and untreated trees had developed a biennial bearing pattern by that time (heavy bloom or “on year’in 1989). Levels of early 13-hydroxylation pathway GAs, viz. GA53, GA19, GA20, GA1 and also GA3, were not altered by treatment. However, GA4, GA7 and GA9 were increased 13.4, 6.5 and 3.8 times, respectively, in seeds of fruit from treated compared to untreated trees. 相似文献
20.
Manuel Talón Peter Hedden Eduardo Primo-Millo 《Journal of Plant Growth Regulation》1990,9(1-3):201-206
The gibberellin (GA) content of the reproductive organs ofCitrus sinensis (L.) Osb., cv. Bianca Comuna and the seedless variety, Salustiana, were examined by combined gas chromatography-mass spectrometry (GC/MS) at different stages of development. Gibberellins A1, A20, and A29 were identified in the reproductive buds of both cultivars 21 days prior to anthesis and in fruits 35 days after anthesis by comparison of their mass spectra and Kovats retention indices with those of standards. In addition, three uncharacterized isomers of GA1 were detected, one in buds and two in fruits. The presence of GA4 in both tissues, and of GA8 in the reproductive buds, was indicated by the occurrence of characteristic ions at the expected retention times, although their spectra were too weak for full identification. Vegetative shoots of cv. Salustiana contained gibberellins A1, A19, A20, and A29, and the unidentified isomer of GA1 present in reproductive buds. The presence of trace amounts of gibberellins A8 and A17 was also indicated. Although the two varieties did not differ qualitatively in the GAs present during flower and fruit development, the seedless variety contained slightly greater amounts. The concentrations of gibberellins A1, A4, and A20 were determined by gas chromatography-selected ion monitoring (GC/SIM) throughout ovary development and early fruit growth. In both varieties, the maximum GA1 concentration occurred at anthesis. Highest concentrations of gibberellins A20 and A4 were found in fruit 35 days after anthesis, although the GA1 concentration at this stage remained low. 相似文献