| selection and characterization of a carrot cell line tolerant to glyphosate. | cultured carrot (daucus carota l.) cells were adapted to growing in 25 millimolar glyphosate by transfer into progressively higher concentrations of the herbicide. tolerance was increased 52-fold, and the adaptation was stable in the absence of glyphosate. the uptake of glyphosate was similar for adapted and nonadapted cells. activity of the enzyme 5-enolpyruvylshikimic acid-3-phosphate synthase was 12-fold higher in the adapted line compared to nonadapted cells, while activities of shikimate de ... | 1984 | 16663884 |
| stimulation of carrot somatic embryogenesis by proline and serine. | serine and proline, when added in a wide range of concentrations to daucus carota cultures during pre-growth in the presence of 2,4-d(2,4-dichlorophenoxyacetic acid), extended in time and quantity the mitotic divisions and stimulated significantly the number of embryos regenerated when the hormone subsequently was omitted from the medium. a specific effect of these amino acids on regeneration is suggested, since proline (as hydroxyproline) and serine are the two major constituents of the cell wa ... | 1984 | 24253519 |
| cross-linking of soluble extensin in isolated cell walls. | the extensin component of primary cell walls has generally been considered to be an intrinsically insoluble cell wall glycoprotein. recent data have established that cell wall extensin is in fact secreted in a soluble monomeric form which slowly becomes insolubilized in the cell wall probably through the oxidative formation of isodityrosine cross-links. we now show that isolated cell walls from aerated root slices of daucus carota have the capacity to insolubilize extensin through the formation ... | 1984 | 16663856 |
| electrical polarity in embryos of wild carrot precedes cotyledon differentiation. | endogenous electrical currents traverse embryos of a higher plant, the wild carrot daucus carota l. current enters the apical pole and leaves the region near the presumptive radicle in the radially symmetric globular embryo. current also enters the exposed surfaces of incipient globular embryos. this electrical polarity precedes differentiation of vascular tissue and cotyledon development. localized current is observed at both growing ends of the embryos in subsequent stages of embryogenesis. in ... | 1984 | 16593519 |
| fusion of spinach mesophyll protoplasts with carrot root parenchyma protoplasts and the effect on spinach chloroplasts. | mesophyll protoplasts of spinach (spinacia oleracea l.) have been fused, using polyethylene glycol, with root parenchyma protoplasts of carrot (daucus carota l.) to enable studies of spinach chloroplasts in a foreign cytoplasm. after 24 h culture, electron microscopy of the fused protoplasts showed many intact chloroplasts, but some chloroplasts were completely disrupted, showing loss of chloroplast envelope and stroma. spinach protoplasts showed normal chloroplast structure 24 h after peg treat ... | 1984 | 23196088 |
| regulation of the shikimate pathway of carrot cells in suspension culture. | the activity of the first enzyme of the shikimate pathway, 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase, is demonstrated in extracts of daucus carota cells grown in suspension culture. maximum specific enzyme activity is found midway through the logarithmic growth of the culture; cells in lag and stationary phases of growth have lower enzyme levels. the enzyme is activated by tyrosine and tryptophan. the extent of activation varies during cell growth. | 1984 | 16663628 |
| comparative effects of ethylene and cyanide on respiration, polysome prevalence, and gene expression in carrot roots. | treatment of carrot roots (daucus carota l.) with 10 microliters per liter ethylene in o(2) evokes a three- to four-fold increase in polysome prevalence and associated poly(a)(+) rna. the increase in polysome prevalence is attended by a similar change in co(2) evolution. the increase in polysomal poly(a)(+) mrna constitutes primarily a generic increase in constitutive mrnas as assayed by in vitro translation. however, changes in the relative abundance of several in vitro translatable ethylene sp ... | 1984 | 16663623 |
| inhibition of flavonoid biosynthesis by gibberellic acid in cell suspension cultures of daucus carota l. | in carrot cells (daucus carota l.), cultured in the presence of gibberellic acid, anthocyanin synthesis is blocked at the level of chalcone synthase. by feeding suitable precursors for anthocyanins (naringenin, eriodictyol, dihydroquercetin) biosynthesis of cyanidin glycosides can be restored. after addition of these substrates to the culture medium in the presence of gibberellic acid, the activity of chalcone synthase remained as low as in the control without precursors. the highest increase in ... | 1984 | 24258782 |
| pectic polysaccharides in carrot cells growing in suspension culture. | pectic polysaccharides in the cell wall of suspension-cultured carrot cells (daucus carota l.) were fractionated into high- and low-molecular-weight components by molecular-sieve chromatography with a sepharose 4b column. during the phase of cell-wall expansion, the relative content of low-molecular-weight polymers rapidly increased. electrophoretic analyses of these fractions showed that the high-molecular-weight components were largely composed of neutral and weakly acidic polymers while the l ... | 1984 | 24258676 |
| the effect of aldicarb on nematode population and its persistence in carrots, soil and hydroponic solution. | aldicarb, temik 15 g, was incorporated in furrows at 3.37 and 6.73 kg ai (active ingredient)/ha and carrots (daucus carota l.) were directly seeded on the same day. the numbers of nematode larvae were significantly suppressed in the treated plots; averages were 249, 74, and 51/50 cc soil samples for control (0), 3.37 and 6.73 kg ai/ha, respectively. aldicarb treatment resulted in a 28% yield increase as compared to the untreated. aldicarb residue in carrots was 28 ppb for the low treatment and 4 ... | 1984 | 6747220 |
| a link between transport and plasma membrane redox system(s) in carrot cells. | carrot (daucus carota l.) cells grown in suspension culture oxidized exogeneous nadh. the nadh oxidation was able to stimulate k+ (86rb+) transport into cells, but it did not affect sucrose transport. n,n'-dicyclohexyl-carbodiimide, diethylstilbestrol, and oligomycin, which only partially inhibited nadh oxidation, almost completely collapsed the k+ (86rb+) transport. vanadate, which is less effective as an ion transport inhibitor, was less effective in inhibiting the nadh-driven transport of k+ ... | 1984 | 6242153 |
| arginine decarboxylase and polyamines required for embryogenesis in the wild carrot. | embryogenic cultures of daucus carota treated with 1 millimolar alpha-difluoromethylarginine, a specific inhibitor of arginine decarboxylase, exhibited nearly a 50 percent reduction in embryo formation compared with controls. putrescine and spermidine concentrations in the treated cells were greatly reduced. addition of putrescine, spermidine, or spermine to the culture medium restored embryogenesis in the treated cultures. embryogenesis was not significantly affected by alpha-difluoromethylorni ... | 1984 | 17746056 |
| reinforced polyproline ii conformation in a hydroxyproline-rich cell wall glycoprotein from carrot root. | the salt-extractable hydroxyproline-rich cell wall glycoprotein from carrot (daucus carota l.) roots is composed of 35% (w/w) protein, 3% (w/w) galactose, and 62% (w/w) arabinose. the arabinose is attached to hydroxyproline as tetra- and trisaccharides. the circular dichroism of the glycoprotein shows that it is completely in the polyproline ii conformation. after deglycosylation of the glycoprotein, the polyproline ii conformation of the peptide backbone was lost. this indicates that the carboh ... | 1984 | 16663405 |
| effect of parental flowering and dispersal times on offspring fate in daucus carota (apiaceae). | seeds collected from parents that flowered at different times were dispersed onto experimental plots at different times during the normal dispersal season. parental flowering and dispersal times, which are correlated with each other, independently affected offspring germination, growth, and time of reproduction. estimated population growth rates were highest for offspring that were dispersed early in the dispersal season and that came from early flowering parents. the data provide evidence that ... | 1983 | 28310498 |
| inactivation of aphidicolin by plant cells. | plant cells are endowed with an aphidicolin inactivating activity. data on cultured cells show that the rate of inactivation depends on the cell type, daucus carota cells being the most effective among the other tested materials (oryza sativa and nicotiana plumbaginifolia). also germinating seedling of haplopappus gracilis and of citrullus vulgaris inactivate aphidicolin.inactivation, which may lead to unexpected results when a prolonged incubation with the drug is required, as in the case of th ... | 1983 | 24258125 |
| orientation and integrity of plasma membrane vesicles obtained from carrot protoplasts. | two fractions enriched in plasma membrane derived from suspension-cultured carrot (daucus carota l.) cells were examined to determine if they differed from each other either in physical nature or in orientation. parameters studied included the protein composition of purified membranes derived from trypsinized and nontrypsinized protoplasts as well as from trypsinized purified plasma membranes, the effect of inhibitors and membrane perturbants on atpase activity, the binding of [acetyl-(14)c]conc ... | 1983 | 16663225 |
| selective inhibition of proline hydroxylation by 3,4-dehydroproline. | the effect of proline analogs on peptidyl proline hydroxylation has been studied in vivo using aerated root slices of daucus carota. one analog, 3,4-dehydroproline, acted at micromolar concentrations to rapidly and selectively inhibit peptidyl proline hydroxylation. a structurally altered hydroxyproline-rich cell wall glycoprotein was synthesized and secreted by dehydroproline-treated tissue. the capacity to hydroxylate proline recovered slowly following a short pulse treatment with the analog, ... | 1983 | 16663215 |
| ozone degrades into hydroxyl radical under physiological conditions : a spin trapping study. | defining the reactants is a critical step towards elucidating the mechanism of ozone toxicity to biomembranes. to document ozone-induced ho.radicals, the spin trap 5,5-dimethyl-1-pyrroline-n-oxide was used and the resulting spin adduct was monitored with electron spin resonance spectroscopy. chelexed potassium phosphate buffer (10 millimolar and 0.2 molar) at ph 7.2 and 7.8 was exposed to ozone (1-40 microliters per liter) by directing a stream of ozone over the surface for 60 seconds. under the ... | 1983 | 16663113 |
| changes in non-cellulosic cell-wall polysaccharides during the growth of carrot cells in suspension cultures. | the cell-wall composition of carrot (daucus carota l.) cells has been studied during their growth in suspension culture. pectic and hemicellulosic polymers were fractionated according to molecular size by a sepharose 4b column. polyuronides in the pectic fraction were resolved into high- and low-molecular-weight components. the low-molecular-weight polyuronides were relatively free of neutral sugars and showed a marked increase during the growth of the cell wall. hemicellulosic polysaccharides w ... | 1983 | 24264546 |
| characteristics of sulfate transport across plasmalemma and tonoplast of carrot root cells. | compartmental analysis of (35)so(4) (2-) exchange kinetics is used to obtain so(4) (2-) fluxes and compartment contents in carrot (daucus carota l.) storage root cells, where 2 to 5% of the so(4) (2-) taken up is reduced to organic form. the necessary curve fitting is verified by (a) consistency between ;content versus time' and ;rate versus time' plots of washout data; (b) agreement between loading and washout kinetics; and (c) correct identification of the fastest exchange phase as being from ... | 1983 | 16662961 |
| effects of aspartate and other compounds on glyphosate uptake and growth inhibition in cultured carrot cells. | the strong correlation between glyphosate uptake and growth inhibition of cultured carrot (daucus carota l. cv danvers) cells incubated in the presence of aspartate suggests that aspartate reverses glyphosate inhibition of growth primarily by reducing intracellular glyphosate concentration. other compounds which reverse glyphosate inhibition of cell growth gave a range of effects on glyphosate uptake: succinate, alpha-ketoglutarate, glutamate, pyruvate, and malate at 10 millimolar and phenylalan ... | 1983 | 16662877 |
| characterization of a selenocystine-resistant carrot cell line : alterations in cystine and sulfate uptake. | a selenocystine-resistant carrot cell line, c-1, was isolated from a haploid carrot (daucus carota) cell culture, ha. the c-1 variant takes up cystine, but not cysteine, more slowly than does ha. the selenocystine resistance is maintained in culture in the absence of selection and is expressed in regenerated plants. results based on chromatographic separation of sulfur metabolites from cells fed with [(35)s]cystine suggest a block either in the uptake or reduction of cystine in the variant. both ... | 1983 | 16662864 |
| kinetics of golgi apparatus membrane flux following monensin treatment of embryogenic carrot cells. | ultrastructural changes resulting from treatment with the sodium selective ionophore, monensin, were studied in embryogenic suspension cultures of carrot, daucus carota (l.) in the presence of 10 microm monensin, an early change in the golgi apparatus was an increase in the number of cisternae per stack (dictyosome). an average of one additional cisterna per stack was formed within the first 2 to 4 min of monensin treatment; in some experiments a second cisterna was formed within about 8 min. th ... | 1983 | 6852059 |
| inhibition of cultured cell growth by tungstate and molybdate. | the growth of suspension cultured cells of nicotiana tabacum (tobacco) was inhibited completely by 100 μm tungstate. even though molybdate reversed the tungstate inactivation of nitrate reductase activity, the growth inhibition was not reversed. the growth inhibition of n. tabacum, daucus carota, glycine max and solanum tuberosum suspension cultured cells by tungstate was similar in media with or without amino acids as a source of reduced nitrogen. only in the case of g. max was a slight reversa ... | 1983 | 24257847 |
| a new flavone glycoside from seeds of daucus carota. | phytochemical examination of seeds of daucus carota l. resulted in the isolation of apigenin -4'-o-beta-d-glucoside, kaempferol-3-o-beta-d-glucoside and a new flavone glycoside which was characterised as apigenin-7-o-beta-d-galactopyranosyl-(1-->4)-o-beta-d-mannopyranoside. | 1982 | 17396982 |
| comparative studies of the phytochrome system in cell cultures from different plants. | phytochrome contents have been assayed in vivo in cell suspension cultures of petroselinum hortense, daucus carota and glycine max. after transferring the cells to fresh medium phytochrome increased in parallel with the increase in cell number, whereas the amount of phytochrome per cell remained constant. the rate of phytochrome reaccumulation after pretreatment with 15 h red light was very similar in all three systems (2.8-3.6 δ(δe) 10(-5)/h). dark reversion and a fast and slow pfr destruction ... | 1982 | 24257714 |
| quantitation of gibberellins and the metabolism of [(3)h]gibberellin a 1 during somatic embryogenesis in carrot and anise cell cultures. | in a carrot (daucus carota l.) cell line lacking the ability to undergo somatic embryogenasis, and in carrot and anise (pimpinella anisum l.) cell lines in which embryogenesis could be regulated by presence or absence of 2,4-dichlorophen-oxyacetic acid (2,4-d), in the medium (+2,4-d=no embryogenesis,-2,4-d=embryo differentiation and development), the levels of endogenous gibberellin(s) (ga) were determined by the dwarfrice bioassay, and the metabolism of [(3)h]ga1 was followed. embryos harvested ... | 1982 | 24271967 |
| analysis of the garden carrot (daucus carota l.) for linear furocoumarins (psoralens) at the sub parts per million level. | | 2014 | 7096793 |
| reversal of glyphosate inhibition of carrot cell culture growth by glycolytic intermediates and organic and amino acids. | various cytokinins and purines were ineffective in reversing glyphosate (0.25 millimolar)-induced growth inhibition of carrot (daucus carota l.) cell suspension cultures. aspartate was particularly effective in reversing glyphosate inhibition, but asparagine and various combinations of lysine, methionine, threonine, and homoserine (eventual products of aspartate metabolism) were not effective. when organic acids of the tricarboxylic acid cycle were added to the medium, particularly good reversal ... | 1981 | 16662096 |
| transfer of liposome-sequestering plasmid dna into daucus carota protoplasts. | reverse-phase evaporation lipid vesicles (rev) liposomes, consisting of phosphatidyl choline and stearylamine in 1:3 molar ratio, encapsulated approximately 30% of exogenously supplied recombinant dna vector, pbr322. the dna sequestered in rev liposomes was highly tolerant to dnase.a two-step procedure was developed, which involves encapsulation of dna with liposomes using one-tenth phosphate-buffered saline-0.5 molar mannitol, followed by incubation of liposome-dna with protoplasts in phosphate ... | 1981 | 16662045 |
| characterization of carrot cell wall protein : ii. immunological study of cell wall protein. | antiserum was raised against a synthetic nona-peptide which was predicted to have considerable homology with the unhydroxylated, unglycosylated precursor of cell wall proteins from several plants. the antiserum is able to recognize the major cell wall protein of incubated carrot (daucus carota) root discs which is produced when the discs are treated with a proline hydroxylase inhibitor and then labeled with radioactive proline. this technique has potential applications in studying cell wall bios ... | 1981 | 16662034 |
| characterization of carrot cell wall protein : i. effect of alpha, alpha'-dipyridyl on cell wall protein synthesis and secretion in incubated carrot discs. | a single glycoprotein accounts for the majority of radioactivity secreted to the cell wall when incubated carrot (daucus carota) discs are labeled with radioactive proline or arabinose. the ferrous chelator alpha,alpha'-dipyridyl prevents the synthesis of this protein. a new proline-labeled protein is made in the presence of alpha,alpha'-dipyridyl and is secreted to the cell wall. the protein has little, if any, carbohydrate attached to it and has a molecular weight of 55,000 daltons. this prote ... | 1981 | 16662033 |
| biotransformation of cardenolides by plant cell cultures1. | a culture of daucus carota cell line ca68, previously shown to specifically hydroxylate digitoxigenin at the c-5 position, has been shown also to convert gitoxigenin and oleandrigenin to their corresponding 5beta-hydroxy derivatives. these two products have not been identified previously. 5beta-hydroxygitoxigenin has been identified by physico-chemical methods and data on its mass spectrum and (13)c-nmr spectrum are reported. 5beta-hydroxyoleandrigenin was identified from its high resolution mas ... | 1981 | 17401955 |
| parameters influencing the liposome-mediated insertion of fluorescein diacetate into plant protoplasts. | maximum uptake of liposome-encapsulated fluorescein diacetate by daucus carota protoplasts was observed when 6 x 10(6) protoplasts per milliliter were incubated with 2.4 x 10(7) liposomes per milliliter for 1 hour. in the case of nicotiana glutinosa protoplasts, optimum ratio of protoplasts to liposomes was 1:10, where 2.3 x 10(5) protoplasts per milliliter were provided. neutral and positive liposomes were found to be efficient vehicles to transfer their contents into plant protoplasts. when pr ... | 1981 | 16661727 |
| predictions of fate from rosette size in four "biennial" plant species: verbascum thapsus, oenothera biennis, daucus carota, and tragopogon dubius. | individual plants were marked in field populations of four biennial plant species, verbascum thapsus l., oenothera biennis l., daucus carota l., and tragopogon dubius scop., and followed for 2 or 3 years. the relationship of both rosette size and age to the probability of an individual dying, remaining vegetative, or flowering was determined for each species. in all four species, a minimum size must be reached before flowering can be induced and above that minimum the probability of flowering in ... | 1981 | 28309802 |
| role of auxin and sucrose in the differentiation of sieve and tracheary elements in plant tissue cultures. | the differentiation of sieve and tracheary elements was studied in callus culture of daucus carota l., syringa vulgaris l., glycine max (l.) merr., helianthus annuus l., hibiscus cannabinus l. and pisum sativum l. by the lacmoid clearing technique it was found that development of the phloem commenced before that of the xylem. in not one of the calluses was differentiation of tracheary elements observed in the absence of sieve elements. the influence of indole-3-acetic acid (iaa) and sucrose was ... | 1980 | 24306691 |
| a clonal analysis of anthocyanin accumulation by cell cultures of wild carrot. | the accumulation of anthocyanin by clones and subclones from a cell suspension culture of wild carrot (daucus carota l.) has been measured under standard conditions. clones which accumulate low amounts of anthocyanin were shown, by recloning after maintenance by serial passage, to have become heterogenous and to contain cells with increased accumulation of anthocyanin. there appears to be a maximum amount of anthocyanin that clones can accumulate. clones which accumulate the maximum amount of an ... | 1980 | 24306302 |
| anthocyanin accumulation and pal activity in a suspension culture of daucus carota l. : inhibition by l-α-aminooxy-β-phenylpropionic acid and t-cinnamic acid. | cells of daucus carota grown in a liquid medium produced large amounts of cyanidin as the only flavonoid aglycon. after inoculation in fresh medium a maximum activity of phenylalanine ammonia lyase (pal; ec 4.3.1.5) was observed within 24 h. l-α-aminooxy-β-phenylpropionic acid (l-aopp), thought to be a competitive inhibitor of pal, inhibited cyanidin accumulation up to 80%. in order to study the regulatory role of pal, the effects of l-aopp and t-cinnamic acid, the product of the deamination of ... | 1980 | 24306300 |
| increase in anthocyanin yield from wild-carrot cell cultures by a selection system based on cell-aggregate size. | wild-carrot (daucus carota l.) cell cultures were screened to yield small (less than 63 μm) or large (greater than 170 μm) cell aggregates which were then subcultured. cultures of the small-size class had a higher, those of the large-size class a lower anthocyanin yield than the unscreened culture. this relationship became accentuated with an increasing number of passages with screening prior to subculture. at the end of six months (12 passages), the pigment yield of the small-size class was tri ... | 1980 | 24306253 |
| 5-fluorouracil resistance in carrot cell cultures : its use in studying the interaction of the pyrimidine and arginine pathways. | physiological studies of 5-fluorouracil (5-fu)-resistant cell line of wild carrot (daucus carota l.), f5, showed that this variant is also resistant to 5-fluorouridine, but is as sensitive to 6-azauracil as the 5-fu-sensitive parent line, woo1c. high levels of exogenous uracil, uridine, and thymine are slightly toxic to f5, but not to woo1c. 5-fu sensitivity in woo1c cannot be reversed by bases and nucleosides; bases like uracil and thymine even increase 5-fu toxicity. no substantial differences ... | 1980 | 24310143 |
| the influence of hygroscopic movement on seed dispersal in daucus carota (apiaceae). | the influence of hygroscopic movement on seed dispersal in daucus carota was examined. when relative humidity increases, umbels containing mature fruits close; when relative humidity drops, umbels open. tests of the effectiveness of smalland large-angled umbels on dispersing seeds under various conditions demonstrate that umbels responding greatly to relative humidity (i.e. opening wide) lose seeds more quickly than do umbels responding little, and do not disperse them as far. as relative humidi ... | 1980 | 28309637 |
| binding of colchicine to a soluble fraction of carrot cells grown in suspension culture. | the binding of [(3)h]colchicine to soluble component prepared from carrot (daucus carota l.) cells in suspension culture was assayed by the diethylaminoethyl(deae)-cellulose powder method. the binding activity was very labile and the time course of the binding indicated that the colchicine-bound complex was also unstable. the reaction was enhanced by vinblastine but lumicolchicine had no effect. the optimum temperature for the reaction was 30° c, and the colchicine binding constant was calculate ... | 1980 | 24306371 |
| quantitative studies of embryogenesis in normal and 5-methyltryptophan-resistant cell lines of wild carrot : the effects of growth regulators. | the frequency of embryo formation was determined in normal and 5-methyltryptophan-resistant (5-mt(r)) cell lines of wild carrot (daucus carota l.) grown in the presence or absence of 2-isopentenyladenine (2-ip) and 2,4-dichlorophenoxyacetic acid (2,4-d). 2-ip stimulated the intitation of embryo formation and also accelerated embryo development. 2.4-d inhibited embryo differentiation at several stages: at 0.1 mg/l, it stopped regeneration at the earliest stage, resulting in callus growth instead ... | 1979 | 24311038 |
| expression of aspartokinase, dihydrodipicolinic acid synthase and homoserine dehydrogenase during growth of carrot cell suspension cultures on lysine- and threonine-supplemented media. | reduction in the amounts of activity of the first enzyme, aspartokinase (ec 2.7.2.4) and two branch-point enzymes, dihydrodipicolinic acid synthase (ec 4.2.1.52) and homoserine dehydrogenase (ec 1.1.1.3), located in the pathway for the synthesis of aspartate-family amino acids, occurred when cell suspension cultures of daucus carota l. var. danvers were grown in media containing 2 mm threonine or 2 mm lysine, endproducts of the pathway. activity of the lysine-sensitive form of aspartokinase was ... | 1979 | 232596 |
| synchronization of somatic embryogenesis in a carrot cell suspension culture. | synchronization of somatic embryogenesis was achieved in a carrot (daucus carota l. cv. "kurodagosun") suspension culture by sieving the initial heterogeneous cell population, by density gradient centrifugation in ficoll solutions, and by subsequent repeated centrifugations at a low speed (50g) for a short time (5 seconds), followed by transferring the cell clusters obtained, which were composed of 3 to 10 cells, to a medium containing zeatin (0.1 micromolar) but no auxin. the frequency of embry ... | 1979 | 16660907 |
| temperature interactions with growth regulators and endogenous gibberellin-like activity during seedstalk elongation in carrots. | stecklings (roots) of three cultivars of carrots (daucus carota l.) were vernalized 10 weeks at 5 c and subsequently grown at each of three greenhouse night/day temperature regimes: high (27/32 c), medium (21/27 c), and low (15/21 c). floral differentiation occurred first in the easy bolting cv. scarlet nantes, intermediate in cv. danvers 126, and last in cv. royal chantenay. stem elongation arising from the subapical meristematic region always preceded floral differentiation. extractable gibber ... | 1979 | 16660856 |
| amino acid levels in carrot cell suspension culture: no correlation with aspartate kinase isoenzyme levels. | free and protein amino acids were analyzed during the growth cycle of a suspension culture of carrot (daucus carota l.) in which there is a 10-fold increase in a lysine-sensitive isoenzyme of aspartate kinase during the early part of the growth cycle. there is little change in either total amino acids or in the amino acids derived from aspartate between 3 and 24 days of culture. it is estimated that the demand for net synthesis of aspartate-derived amino acids is decreased as the growth rate dec ... | 1979 | 16660772 |
| derepression and repression of lysine-sensitive aspartokinase during in vitro culture of carrot root tissue. | the increment of lysine-sensitive aspartokinase (ec 2.7.2.4) activity during in vitro culture of carrot (daucus carota, cv. oogata sanzun) root tissue was explained in terms of derepression caused by an earlier decrease in the endogenous level of lysine, a possible end product repressor. tissue content of free lysine decreased to about one-third of the initial level after 1 day of culture and no lysine was detected in the 2nd day. inclusion of lysine (0.1 to 1.0 millimolar) in the culture medium ... | 1979 | 16660771 |
| freeze preservation of somatic embryos and clonal plantlets of carrot (daucus carota l). | cell suspensions of carrot (daucus carota l.) can be cryopreserved by slow freezing (about 2 c per minute) in medium containing dimethylsulfoxide as a cryoprotectant. after storage in liquid nitrogen and thawing they demonstrate a high viability and are able to resume growth. such a method entirely fails to preserve clonal plantlets; somatic embryos cease organized development at the time of freezing and recover growth only by secondary embryogenesis. modification of the procedure, involving the ... | 1979 | 16660748 |
| polyamine metabolism in embryogenic cells of daucus carota: ii. changes in arginine decarboxylase activity. | embryogenic cultured cells of daucus carota have been shown to synthesize putrescine from exogenously supplied [(14)c]arginine at twice the rate of control nonembryogenic cells. in the present paper, the activity of arginine decarboxylase (arginine carboxy-lyase, ec 4.1.1.19), an important enzyme in the synthesis of putrescine, was assayed and also found to be elevated by as much as 2-fold in embryogenic cells. this difference between embryogenic and nonembryogenic cells was observed as early as ... | 1979 | 16660725 |
| changing fatty acid composition during somatic embryogenesis in cultures of daucus carota. | the fatty acid composition of five embryo stages following the induction of embryogenesis in cultures of daucus carota have been studied. quantitative rather than qualitative changes in fatty acid content were observed, although globular embryos do possess some fatty acids of long (c 20 and above) chain length not observed in earlier or later stages in development. the major fatty acids present were c 16:0, 18:0, 18:1, 18:2 and 18:3. | 1979 | 24407389 |
| transfer of organelles of the alga chlamydomonas reinhardii into carrot cells by protoplast fusion. | a mutant of chlamydomonas reinhardii which lacks a cell wall was fused with daucus carota protoplasts using polyethylene glycol and the resulting fusion products were cultured. fusion involved integration of chlamydomonas and carrot plasma membranes and the release of algal organelles into the carrot cytoplasm. chlamydomonas basal bodies, nuclei and chloroplasts were frequently observed in the fusion products. cultured fusion products regenerated cell walls and divided; most chlamydomonas organe ... | 1979 | 24407323 |
| biosynthesis of myo-inositol and its role as a precursor of cell-wall polysaccharides in suspension cultures of wild-carrot cells. | the biosynthesis of myo-inositol (mi) and its role as a precursor of cell-wall polysaccharides was studied in supension cultures of wild carrot (daucus carota l.) cells. suspension cultures, grown in the presence or absence of 2,4-dichlorophenoxyacetic acid for 7 and 14d were incubated with [u-(14)c]glucose and [2-(3)h]mi in the presence of different concentrations of unlabeled mi. synthesis of [(14)c]mi from [u-(14)c]glucose occurred under all conditions. the amount of mi synthesized from gluco ... | 1979 | 24317946 |
| biosynthesis of cell-wall polysaccharides in cultured carrot cells. | biosynthesis of the cell wall in carrot cells (daucus carota l.) cultured in a synthetic liquid medium was studied by measuring the incorporation of radioactive glucose and myo-inositol (mi). when the cells were fed with [(14)c]glucose in the presence of 0.01% mi, the label soon appeared in the neutral sugars in the cell wall but little radioactivity was found in the uronic-acid residues even after a prolonged incubation. on the other hand, radioactivity derived from [(3)h]mi was found to be dis ... | 1979 | 24317945 |
| relationship of indole-3-acetic acid and tryptophan concentrations in normal and 5-methyltryptophan-resistant cell lines of wild carrots. | a 5-methyltryptophan(5-mt)-resistant cell line of wild carrot (daucus carota l.), w001, that exhibited auxin-independent callus growth, was found to accumulate indole-3-acetic acid (iaa) and tryptophan (trp). anthranilate-synthetase activity in w001 cell extract was less sensitive to feedback inhibition by trp than in the original 5-mt-sensitive cell lines. it is hypothesized that the resistant enzyme allowed more trp synthesis and accumulation which, in turn, affected the iaa concentration in t ... | 1979 | 24317760 |
| regulatory isoenzymes of aspartate kinase and the control of lysine and threonine biosynthesis in carrot cell suspension culture. | aspartate kinase (ec 2.7.2.4) from carrot (daucus carota l.) cell suspension culture has been partially resolved into lysine-sensitive and threonine-sensitive components by gel filtration chromatography. the yield of lysine-sensitive aspartate kinase changed independently of the yield of the threonine-sensitive activity during the 4-week growth cycle of the culture, and this provides additional evidence for the existence of two independently regulated isoenzymes. exogenously supplied lysine and ... | 1978 | 16660554 |
| polyamine metabolism in embryogenic cells of daucus carota: i. changes in intracellular content and rates of synthesis. | changes in the metabolism of polyamines, which seem to be involved in transcription and translation in animal systems, have been studied in cultured cells of daucus carota (carrot) undergoing embryogenesis. putrescine levels were elevated by as much as 2-fold over the control within 24 hours after transfer of the cells to embryogenic medium. spermidine levels were elevated also but spermine levels appeared to be lower in embryogenic cells. embryogenic cells incorporated [(14)c]arginine into putr ... | 1978 | 16660531 |
| inhibition of deoxyribonuclease activity in the medium surrounding plant protoplasts. | after 1 hour, exogenous deoxyribonucleic acid was degraded within a culture medium at 25 c (ph 6) containing protoplasts of daucus carota l. var. sativa. low temperature incubation (1 c) or the addition of 45 millimolar sodium citrate to the medium eliminated dnase activity for at least 4.5 hours. this dnase activity was not reduced at ph 7 or 9, nor by addition of 200 millimolar adenosine 5'-triphosphate.techniques were developed to ensure high protoplast plating efficiencies and high regenerat ... | 1978 | 16660499 |
| morphogenetic responses of cultured totipotent cells of carrot (daucus carota var. carota) at zero gravity. | an experiment designed to test whether embryos capable of developing from isolated somatic carrot cells could do so under conditions of weightlessness in space was performed aboard the unmanned soviet biosatellite kosmos 782 under the auspices of the joint united states-soviet biological satellite mission. space flight and weightlessness seem to have had no adverse effects on the induction of embryoids or on the development of their organs. a portion of the crop of carrot plantlets originated in ... | 1978 | 17847331 |
| electron microscopic studies in cultivated plants. ii. fresh and stored roots of daucus carota l. | scanning (sem) and transmission (tem) electron microscopic studies in fresh and stored roots (4 months at an average temperature of +8 degrees c) of daucus carota l. (carrots) were carried out. chief stress was laid on the analysis of the histological and cytological structure of the secondary phloem parenchyma cell. sem images show the three-dimensional histological arrangement of the cells. moreover, the outlines of lipid droplets, mitochondria, starch grains, and carotin pigment crystals are ... | 1978 | 636662 |
| dna, rna and protein content of tissue during growth and embryogenesis in wild-carrot suspension cultures. | a highly selected population of cells (clumps from 63 to 125 micron in diameter), obtained by screening 14-day-old stock suspension cultures of wild carrot (daucus carota l.), was used to initiate cultures in this study. time-course changes in dna, rna and protein were followed when these cultures were grown in the presence or absence of 2.25 mum 2,4-dichlorophenoxyacetic acid (2,4-d). the data show that growth of these cultures, particularly in the early part of the growth curve, is different f ... | 1978 | 669724 |
| growth and embryo formation in wild-carrot suspension cultures with ammonium ion as a sole nitrogen source. | wild-carrot (daucus carota l.) suspension cultures grew and produced embryos on ammonium ion as a sole source of nitrogen in the absence of any exogenous kreb's cycle acid when the ph of the medium was controlled by continuous titration with with koh or khco3. | 1978 | 27444 |
| regulation of lysine and threonine synthesis in carrot cell suspension cultures and whole carrot roots. | aspartokinase (ec 2.7.2.4), homoserine-dehydrogenase (ec 1.1.1.3) and dihydrodipicolinic-acid-synthase (ec 4.2.1.52) activities were examined in extracts from 1-year-old and 11-year-old cell suspension cultures and whole roots of garden carrot (daucus carota l.). aspartokinase activity from suspension cultures was inhibited 85% by 10 mm l-lysine and 15% by 10mm l-threonine. in contrast, aspartokinase activity from whole roots was inhibited 45% by 10 mm lysine and 55% by 10 mm threonine. this dif ... | 1978 | 24414879 |
| oleosomes (spherosomes) from daucus carota suspension culture cells. | isolated oleosomes from daucus carota l. cells are lipid droplets consisting mainly of triacylglycerols (>97%) and very little protein (1-2%). the boundary between the lipid phase and the cytosol, which is visible on electron micrographs, is not built up by a true phospholipid-containing unit or half unit membrane. enzymatic activities of lipid metabolism were not found to be associated with oleosomes with the exception of very low (contaminating) acyl-coa:1,2-diacylglycerol acyltransferase (ec ... | 1978 | 24414559 |
| lipids, lipid turnover, and phospholipase d in plant suspension culture cells (daucus carota). | the lipid pattern of daucus carota l. suspension culture cells and other plant cell strains was analyzed. phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, and triacylglycerol were the main components. the characteristic plastidal and mitochondrial lipids could also be identified. all strains tested exhibited a phospholipase d activity. several lipid precursors were found to be well utilized by the cells and to be special markers for certain lipids or parts of the lipid molecu ... | 1978 | 24414107 |
| isolation and identification of substances inducing formation of tracheary elements in cultured carrot-root slices. | the roots of a carrot (daucus carota l.) cultivar, kuroda-gosun, contain active substances causing formation of tracheary elements in cultured root phloem slices. in the roots of another carrot cultivar, hokkaidô-gosun, such substances could not be detected but when root-phloem slices of this cultivar were cultured in the light, active substances were produced in the tissue. from the behavior in thinlayer chromatography and data from gas chromatography and mass spectrometry, the major active sub ... | 1978 | 24413942 |
| the influence of gibberellic acid on reassociation kinetics of dna of daucus carota l. | carrot dna, extracted from the tap root of untreated and gibberellic acid (ga3)-treated plants and of different varieties, was analyzed by reassociation kinetics. differences due to ga3 treatment appear mainly in the intermediate repeated dna region. differences in approximately the same region are found using carrot dna of different varieties, which also show differences in the slow reassociating sequences. by hybridizing a "family" of the "unique" dna range with dna obtained from ga3-treated p ... | 1978 | 24408253 |
| change in the proportion of two aspartokinases in carrot root tissue in response to in vitro culture. | two isofunctional aspartokinases (ec 2.7.2.4) exist in fresh root tissue of carrot (daucus carota, cv. oogata sanzun). the threoninesensitive portion constitutes about 70% of the activity; the lysinesensitive, less than 20%. culture of slices of carrot tissue for 3 days reversed the ratio as the lysine-sensitive activity preferentially increased. inhibition by threonine and lysine was additive in both enzyme preparations from fresh and cultured tissues. the activities were resolved into two dist ... | 1978 | 16660222 |
| [flavonols and flavones of vegetables. viii. flavones of carrot leaves (author's transl)]. | the flavonoid constituents of carrot leaves (daucus carota l. ssp. sativa) were separated by means of cellulose column chromatography, and the following compounds were obtained crystalline and identified by usual procedures: luteolin 7-beta-d-glucoside as the main flavon, luteolin 4'-beta-d-glucoside, luteolin 7-beta-d-glucuronide, apigenin 7-beta-d-glucoside, apigenin 7-rutinoside, chrysoeriol 7-beta-d-glucoside. luteolin 7-rutinoside also was identified, but could not be obtained crystalline. | 1977 | 595898 |
| effects of ethephon, ethylene, and 2,4-dichlorophenoxyacetic acid on asexual embryogenesis in vitro. | asexual embryogenesis in daucus carota l. ;queen anne's lace' callus was suppressed by ethephon, ethylene, and 2,4-dichlorophenoxyacetic acid (2,4-d). the ethephon effect could be attributed to volatile and nonvolatile substances. the volatile component was probably entirely ethylene. ethylene was liberated in the cultures in direct proportion to ethephon added to the medium. autoclaving of ethephon caused a substantial decrease of measurable ethylene. continuous exposure of callus to 5 mul/l et ... | 1977 | 16660109 |
| somatic hybridisation of daucus carota and d. capillifolius by protoplast fusion. | protoplasts isolated from cultured cells of albino carrot (daucus carota) and normal green d. capillifolius were fused by polyethylene glycol. selection of somatic hybrid plants was based on the restoration of photosynthetic function in hybrids. green plantlets selected from embryo cultures were characterized on the basis of leaf morphology. the interspecific protoplast fusion resulted in green plants with leaves which were intermediate between those of the parents. the somatic hybrids between o ... | 1977 | 24317689 |
| morphometric measurements of daucus carota suspension culture cells. | standard stereologic methods have been applied to electron micrographs of daucus carota l. suspension culture cells. the relative frequencies of the different membrane systems within the cells have been determined and compared with published data form mature leaf cells. | 1977 | 24420523 |
| purification and substrate specifities of hydroxycinnamate: coa ligase from anthocyanin-containing and anthocyanin-free carrot cells. | callus cells of daucus carota l. have different phenylpropanoid pathways depending on the medium composition. cells propagated on a medium with gibberellic acid do not accumulate cyanidin but incorporate [(14)c]phenylalanine into chlorogenic acid at a high rate. cells grown on a medium free of gibberellic acid accumulate cyanidin in very large amounts. we here describe partial purification of hydroxycinnamate: coa ligase, and its properties in these two cell lines. the enzymes extracted from the ... | 1977 | 24420100 |
| synthesis of phenylalanine ammonia-lyase in anthocyanin-containing and anthocyanin-free callus cells of daucus carota l. | when callus cells of daucus carota are grown on a medium containing gibberellic acid (ga3) in a physiological concentration of 3x10(-6) m the cells cease to accumulate anthocyanins. this anthocyanin-free cell line has a very low activity of phenylalanine ammonia-lyase. after density labelling with d2o an intensive de novo synthesis of the phenylalanine ammonia-lyase (e.c. 4.3.1.5; pal) in the anthocyanin-containing cells does occur. 58% of the c-bound h-atoms are replaced by deuterium. the antho ... | 1977 | 24419894 |
| relation between auxin autotrophy and tryptophan accumulation in cultured plant cells. | auxin autotrophy was studied in cultured carrot (daucus carota l.), tobacco (nicotiana tabacum l.), and potato (solanum tuberosum l.) cell lines. of 10 carrot lines resistant to 5-methyltryptophan (5mt), which accumulate free tryptophan (trp) because of an altered control enzyme, 5 were auxinautotrophic while the normal parent line was not. carrot lines selected from the same parent line as resistant to other amino-acid analogs were not auxinautotrophic, like the parent. the only 5mt-resistant p ... | 1977 | 24419686 |
| influence of carbohydrates on quantitative aspects of growth and embryo formation in wild carrot suspension cultures. | wild carrot (daucus carota l.) cell suspensions were grown on a mineral salt medium supplemented with 10 mmmyoinositol in the presence and absence of 2.25 mum 2,4-dichlorophenoxyacetic acid (2,4-d), and a variety of carbon sources.the data obtained on growth and embryo number in the absence of 2,4-d show that wild carrot suspensions were able to utilize sucrose, glucose, fructose, galactose, mannose, maltose, raffinose, or stachyose as a carbon source. a highly significant correlation between dr ... | 1977 | 16659793 |
| rapidly-labelled rna species isolated from cell suspensions of daucus carota. | | 1977 | 918306 |
| phenylalanine-ammonia-lyase activity and biosynthesis of anthocyanins and chlorogenic acid in tissue cultures of daucus carota (author's transl). | | 1976 | 981382 |
| estrogenic and pregnancy interceptory effects of carrot daucus carota seeds. | | 1976 | 992821 |
| on the mechanism of the uptake of vaucheria chloroplasts by carrot protoplasts treated with polyethylene glycol. | chloroplasts from the alga, vaucheria dichotoma (l.) ag., are taken up into protoplasts of carrot (daucus carota l.) during polyethylene-glycol treatment. since chloroplasts are found with equal frequency in uni- and multinucleate protoplasts, chloroplast uptake does not depend on protoplast fusion. however, higher frequencies of chloroplast uptake are observed when experimental conditions favor greater aggregation of protoplasts. the intracellular localization of chloroplasts is confirmed by el ... | 1976 | 24424824 |
| variation of cell cycle duration within suspension cultures of daucus carota and its consequence for the induction of ploidy changes with colchicine. | | 1976 | 935509 |
| the duration of the cell cycle of daucus carota l. in vivo and in vitro. | | 1975 | 1132430 |
| involvement of the golgi apparatus in the synthesis and secretion of hydroxyproline-rich cell wall glycoproteins. | pulse labeling of carrot root phloem parenchyma (daucus carota l. cv. nantes) tissue with (14)c-proline followed by fractionation of the cytoplasmic organelles on sucrose gradients was used to determine the identity of the membranous organelles involved in the secretion of the hydroxyproline-rich glycoproteins of the cell wall. identification of the organelles was done through electron-microscopical observations and through the localization of marker enzymes on the sucrose gradients. enrichment ... | 1975 | 16659117 |
| release of hydrolytic enzymes from the cell walls of intact and disrupted carrot callus tissue. | the effect of ionic strength and ph on the solubility of acid invertase (e.c. 3.2.1.26.) and α-glucosidase (e.c. 3.2.1.20.) from carrot daucus carota l. tissue cultures is presented. the action of these two factors on disrupted tissue is contrasted with the effects of the same treatment on the solubility of these enzymes from intact tissue. the results are discussed in terms of a unified theory on the solubility behaviour of acid invertase and other hydrolytic enzymes in plant cells. | 1975 | 24430368 |
| [induction of anthocyanin biosynthesis in tissue cultures of daucus carota (author's transl)]. | | 1975 | 1187875 |
| the control of glycolysis in aged slices of carrot root tissue. | the possibility that the rate of glycolysis in aged slices of carrot (daucus carota l.) is controlled by the enzyme phosphofructokinase was examined, by changing the rate of metabolism, by supplying the tissue with potassium chloride, potassium phosphate and potassium citrate and measuring the subsequent changes in levels of metabolites. potassium chloride and potassium phosphate stimulate glycolysis, potassium citrate inhibits glycolysis and the associated changes in metabolites are consistent ... | 1974 | 24442325 |
| the pasteur effect in carrot root tissue. | the presence of a pasteur effect in aged discs of carrot (daucus carota l.) storage tissue and its apparent absence in fresh discs was confirmed. changes in the concentration of glycolytic intermediates have been determined, following the transfer of fresh and aged discs from air to nitrogen. in addition the changes in glycolytic intermediates associated with the ageing of the discs have also been measured. the results are analysed and interpreted to indicate that in aged discs the enzyme phosph ... | 1974 | 24442324 |
| [relationship between anthocyanin synthesis and activity of phenylalanine ammonia-lyase (pal) in callus cells of daucus carota]. | two celllines from daucus carota callus were tested for phenylalanine ammonia-lyase activity. the white callus (dcw) has only 15% of the enzyme activity of the blue callus (dcb). the enzyme activity reaches a maximum value after a cultivation period of 21 days, whereas the maximum in anthocyanin content is reached after 28 days. we can demonstrate here a good correlation between one of the enzymes and the end product of the anthocyanin biosynthesis.the crude extract from dcw cells has no inhibit ... | 1974 | 24458301 |
| fluxes of a nonelectrolyte and compartmentation in cells of carrot root tissue. | permeation of thiourea into cells of carrot (daucus carota l.) storage root discs was found to be governed by its concentration gradient only. the analysis of the course of thiourea efflux from preloaded discs shows two distinct exponential curves, apart from an initial very fast component. reasons are given for relating the first exponential part of the curve to efflux from the cytoplasm and the second exponential part to efflux from the vacuole.the rate constant for thiourea efflux through the ... | 1974 | 16658696 |
| transfer of algal chloroplasts into protoplasts of higher plants. | polyethylene-glycol treatment of mixed suspensions of isolated protoplasts and of chloroplasts induces chloroplast uptake by the protoplasts. chloroplasts of algal origin (vaucheria dichotoma (l.) ag.) were transferred with high frequency into protoplasts of daucus carota l. | 1974 | 24442619 |
| investigations on the growth and metabolism of cultured explants of daucus carota : v. effects of trace elements and growth factors on the solutes accumulated. | earlier papers of this series relate to different growth-promoting substances and systems which, singly and in combination, have interacted with trace elements (mn and mo) and fe to induce growth and to affect the metabolism of aseptic cultures of carrot. the solutes of cultured carrot cells (k(+), na(+), cl(-), total solutes) are also affected. two clones were grown in 9 combinations of growth factors and under 4 trace-element regimes (a complete complement including fe, and this complement lac ... | 1973 | 24469575 |
| ethylene-induced phenylalanine ammonia-lyase activity in carrot roots. | ethylene enhanced the activity of phenylalanine ammonialyase in carrot (daucus carota l., var. "nauty") root tissue. slight increase in enzyme activity was exhibited by root discs incubated in ethylene-free air. it was probably due to the ethylene formed within the sliced tissue. addition of ethylene to the air stream increased phenylalanine ammonia-lyase activity and the total protein content of the discs until maximum activity was reached after 36 to 48 hours of incubation. the continuous pres ... | 1973 | 16658459 |
| further studies on the photosynthesis of carrot tissue cultures. | the influence of kinetin and sucrose on the photosynthetic activity of carrot (daucus carota) tissue cultures in relation to growth was investigated. the results showed that light contributes heavily to the growth of tissue cultures measured in terms of fresh and dry weight and cell division activity. in light, the fresh weight, dry weight, and number of cells per explant were about or more than doubled. this indicated that after the development of chloroplasts, carrot tissue cultures can grow a ... | 1973 | 16658393 |
| isolation and properties of deoxyribonucleic acid from protoplasts of cell suspension cultures of ammi visnaga and carrot (daucus carota). | a procedure is described for the isolation of native dna from protoplasts of ammi (ammi visnaga) and carrot (daucus carota) cells. protoplasts were produced from 40 grams of fresh cells by enzyme hydrolysis and lysed with sodium dodecyl sulfate. the dna was purified by treatment with pronase and ribonuclease. final isolation was achieved by sucrose density gradient centrifugation.the melting temperature of ammi and carrot dna in 0.15 m nacl and 15 mm trisodium citrate buffer, ph 7.0, was 84.0 c ... | 1972 | 16658166 |
| anthranilate synthetase from 5-methyltryptophan-susceptible and -resistant cultured daucus carota cells. | | 1972 | 4652566 |
| induced changes in permeability of plant cell membranes to water. | the half-time for tho equilibration was three times longer for a living carrot (daucus carota l.) cylinder than for a dead one. furthermore, the energy of activation of tho flux was more than twice as high for the living cylinder. passage through living membranes thus constitutes a rate-limiting step for tho flux in carrot tissue.co(2) increased the half-time (t((1/2))) for tho equilibration. treatment with abscisic acid or with tertiary butanol decreased t((1/2)). in neither case was the select ... | 1972 | 16658009 |
| the greening of chromoplasts in daucus carota l. | evidence was obtained for the transformation of chromoplasts to chloroplasts in the cortex parenchyma of carrot during exposure to light. typical chromoplasts containing carotene crystals but no lamellar system were observed at the onset of illumination. the ensuing synthesis of chlorophyll and a lamellar system was accompanied by disappearance of the carotene crystals. only chloroplasts were present after 48 hr in the light. the different stages of plastid development were observed using the el ... | 1971 | 24493398 |
| investigations on the growth and metabolism of cultured explants of daucus carota : iv. effects of iron, molybdenum and the components of growth promoting systems and their interactions. | the induction and maintenance of growth in small, standard explants of carrot root exposed to a trace-element-free basal nutrient medium (b (**)) have been investigated. the organic growth factors that induce the growth are complex as represented by a trace-element-limited coconut-milk preparation (cm(**)) or the component parts of distinct growth promoting systems mediated by inositol or by 3-indoleacetic acid (iaa). in system i inositol interacts with growth factors from aesculus, of which a k ... | 1971 | 24487636 |
| [structure of the carotene crystals of daucus carota]. | | 1971 | 5555933 |
| phytochrome in cultured wild carrot tissue: ii. dark transformations. | disappearance and transformation of phytochrome in light-treated, dark-grown cultured tissue of wild carrot (daucus carota l.) have been analyzed. evidence is presented for the existence of two populations of far red-absorbing phytochromes: one which is subject to reversion, and a second which undergoes loss of photoreversibility. phytochrome levels and transformation characteristics have been compared for several strains and developmental stages of cultured wild carrot tissue. | 1970 | 16657464 |