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Eco-friendly biosynthesis of nanoparticles from medicinal plants as reducing agent has gained importance due to its potential therapeutic uses. In the present study Silver nanoparticles (AgNPs) were eco-friendly synthesized using the leaf extracts of the medicinal plant Tropaeolum majus. The obtained AgNPs were characterized by UV - visible spectrum, FTIR, SEM and XRD which clearly showed the reduction of Ag+ ions to Ag0. In addition, the aqueous and ethanolic extracts were analyzed for phytochemicals and its antioxidant activities. GC–MS spectrum showed the presence of 25 compounds with benzeneacetic acid as the dominant contents. The synthesized AgNPs revealed maximum absorption spectrum at 463 nm and FTIR vibrational peaks at 3357.46, 21,966.52, 2118.42, 1637.27, 658.571 and 411.728 cm−1 respectively. SEM and XRD studies evidenced the nature of nanocrystalline with face centered cubic (fcc) crystal structure. Both AgNPs and plant extracts showed more inhibition activity against Pseudomonas aeroginosa compared to other bacteria with MIC value of 6.25 μg/ml. Antifungal activities was higher for Penicilium notatum with MIC value 31.2 μg/ml. The IC50 values for MCF7 for aqueous extract were found to be 4.68 μg/ml, ethanol extract 7.5 μg/ml, AgNPs 2.49 μg/ml, and doxorubicin 1.4 μg/ml. The IC50 values for VERO cell line for aqueous extract was 8.1 μg/ml, ethanol extract with 6.8 μg/ml, silver nanoparticles 5.3 μg/ml and doxorubicin 2.6 μg/ml respectively. Conclusively, the antibacterial, antifungal, antioxidant and anticancer properties of the synthesized AgNPs from Tropaeolum majus act as major therapeutic drug for microbial infectious disease and other health associated disorders.

This work reported the natural dyes extracted from yellow and orange Nasturtium (Tropaeolum majus) flower petals and then used them as sensitizer in dye-sensitized solar cells (DSSCs) for the first time. The functional groups present in the dyes were identified by FTIR spectroscopy which revealed the characteristic peaks of pigments anthocyanins and carotenoids. The UV–Visible analysis of dye extracts showed absorption in the visible region and the dye loaded TiO2 exhibited broad absorption. The density functional theory (DFT) calculation was performed on Lutein, Cyanidin-3-sophoroside, Delphinidine-3-dihexoside and Pelargonidin-3-sophoroside to find out the HOMO and LUMO levels of each. The DSSCs were constructed using these natural extracts as sensitizer dye and photovoltaic performance such as conversion efficiency (η), short-circuit current density (Jsc), open-circuit voltage (Voc) and fill factor (FF) were investigated. The electrochemical impedance spectroscopy (EIS) studies were performed to analyze the charge transfer characteristics. The light-to-electricity conversion efficiency of 0.28% is achieved with Voc of 0.556 V, Jsc of 0.72 mA/cm2 and FF of 0.70 for natural sensitizer extracted from orange petals of Nasturtium flowers.

Background Nasturtium (Indian cress, Tropaeolum majus) is known for its pharmacological value in the treatment of bacterial infections of the upper air tract and urinary bladder. However, scientific data on the anti-inflammatory potency in human-derived cells is missing. Purpose The aim of this study was to investigate the potential of nasturtium to inhibit the lipopolysaccharide (LPS) induced inflammatory response in primary human cells of the immune system. Study design The anti-inflammatory activities of nasturtium and its fractions were evaluated via regulation of arachidonic acid (AA) pathway and MAPK kinase cascade. Fraction H4 which was responsible for the anti-inflammatory effects was further characterized. Methods Human peripheral blood mononuclear cells (PBMC) were either treated with plant extracts or fractions thereof, stimulated with LPS and/or N-formyl-methionyl-leucyl-phenylalanine (fMLP) and analysed for COX and LOX, release of prostaglandin PGE2, leukotriene LTB4, TNF-alpha and ERK signaling pathway activation. The plant extracts were separated into four fractions by HPLC; fraction H4 was subjected to UHPLC-ToF/MS analysis to identify potential bioactive compounds. Results We found that aqueous extracts of nasturtium did exert strong concentration dependent suppression of LPS-triggered TNF-alpha release and COX pathway signaling, including PGE2 synthesis. Whereas COX-1 protein expression was not impacted, LPS-triggered COX-2 protein expression was concentration dependently blocked by the plant extract but not COX-2 enzyme activity. These findings suggest a mechanism of action for the plant extract which is different from non-steroidal anti-inflammatory drugs (NSAIDs). Moreover, the plant extract blocked leukotriene LTB4 release, the major end product of the 5-LOX pathway from PBMC. Down-regulation of ERK1/2 and c-Jun activation preceded COX-2 suppression upon plant extract treatment in the presence of LPS. Using HPLC separation of the aqueous extract followed by metabolomic analysis we could limit the number of relevant bioactive compounds in the extract to about 50. Conclusions This study provides a rationale for the anti-inflammatory efficacy of nasturtium observed in man and gives first insight into the underlying molecular mechanisms.

The glucosinolate (GSL) content is an important quality parameter of crops, such as mustard, horseradish or nasturtium, which are grown for their taste as condiments or for medical purposes. Accordingly, an enhancement of the GSL content should promote the large-scale cultivation of these plants. It is well known that GSLs reveal a high significance in plant defense, and that several stress factors cause an increase in the GSL concentration. The goal of the present study was to evaluate the means to stimulate the GSL biosynthesis during plant growth by applying moderate stress. The impact of different treatments on the GSL content and on growth of Tropaeolum majus L. was investigated in a greenhouse trial. Moderate stress was induced by drought, by the addition of salt, or the application of growth regulators (methyl jasmonate, salicylic acid). Moreover, cell wall lysate was applied to the plants to mimic biotic stress, such as pathogen attack. Evapotranspiration (ETP), biomass development, specific leaf weight (SLW), plant pigments, and thiol contents had been recorded to evaluate physiological changes in response to the treatments. The glucotropaeolin (GT) content, representing the sole GSL of T. majus was measured as target compound. Drought and MeJA application increased the GT concentration on dry weight basis and impacted on ETP, dry matter content, SLW and plant pigments, too. Application of salt, SA and cell wall lysate did not affect the GT concentration in a consistent way. Moderate drought and the application of MeJA are suitable tools to increase the GT concentration in T. majus . However, in case of drought the higher GT concentration was only reached at the expense of biomass production. High GT concentrations together with reasonable yields were only achieved by MeJA application.

The aim of our study was to determine antioxidant activity of aqueous and hydroethanolic extracts obtained from both freeze-drying leaves and flowers, as well as juice squeezed from the fresh herb of Tropaeolum majus L. In cell-free systems the scavenging of synthetic radical (DPPH) and two radicals (O 2 − , H 2 O 2 ) was evaluated. In in vitro experiments, the effect on reactive oxygen species (ROS) production by f-MLP-stimulated neutrophils, as well as the effect on ROS generation by human skin fibroblasts after UV irradiation were determined. In studies on fibroblasts, the protective effect of the extracts/juice against cell membrane damage caused by UV irradiation was also tested. The tested extracts/juice were chemically characterized by the determination of the content of flavonoids, total phenols and ascorbic acid. Scavenging activity of the tested extracts/juice against synthetic radical-DPPH was low. Against H 2 O 2 and O 2 − the extracts showed stronger antioxidant activity, while the juice was significantly active only against O 2 − . In the human neutrophils model the hydroethanolic extract most strongly inhibited production of ROS. The weakest activity was shown by the juice. Studies on human skin fibroblasts showed no cytotoxic activity of the tested extracts/juice. We also observed inhibition of ROS production by tested extracts/juice induced by UVA as well as by UVB irradiation. The strongest inhibition of ROS production after UVA irradiation was shown by the juice, while after UVB irradiation the most potent was the hydroethanolic extract. Our results partly explain the use of extracts from nasturtium in skin diseases, such as sunburns.

The aim of this study was comparison of antioxidant, anti-inflammatory, and antimicrobial activity, as well as chemical composition of extracts of Tropaeolum majus L. herb. Aqueous and hydroethanolic extracts derived from dried and freeze-dried nasturtium herb, prepared both at room temperature and at 90 °C, were studied. In the studies there were no significant differences between antioxidant activity of the extracts. All extracts showed scavenging activity against all the examined reactive species in a concentration-dependent manner. The strongest scavenging activity they showed against reactive nitrogen species, NO (SC50 4.54 ± 0.26–10.90 ± 1.39 μg/mL) and ONOO − (SC50 2.49 ± 1.50–6.37 ± 1.86 μg/mL). Among reactive oxygen species, they showed strong scavenging activity against H 2 O 2 (SC50 14.90 ± 3.91–38.63 ± 9.28 μg/mL). Scavenging activity against O 2 − was weaker, while against HClO the extracts showed very weak activity, practically at the level of statistical error. Against synthetic radical – DPPH scavenging activity of the tested extracts was negligible. The extracts demonstrated stronger antioxidant activity in ex vivo experiment on human neutrophils. The extracts showed no inhibitory activity on hyaluronidase, but at a concentration of 50 μg/mL they inhibited the activity of COX1 by approximately 60%. Lack of antimicrobial activity of the extracts seems to be associated with a low content of benzyl isothiocyanate. The aqueous extracts were characterized by the presence of esters of quinic acid with cinnamic acids (chlorogenic acids, p-coumaroylquinic acids) and the presence of flavonoids. Meanwhile the hydroethanolic extracts were mainly rich in the above mentioned acid esters.

A deep-sequencing approach was pursued utilizing 454 and Illumina sequencing methods to discover new genes involved in xyloglucan biosynthesis. cDNA sequences were generated from developing nasturtium (Tropaeolum majus) seeds, which produce large amounts of non-fucosylated xyloglucan as a seed storage polymer. In addition to known xyloglucan biosynthetic genes, a previously uncharacterized putative xyloglucan galactosyltransferase was identified. Analysis of an Arabidopsis thaliana mutant line defective in the corresponding ortholog (AT5G62220) revealed that this gene shows no redundancy with the previously characterized xyloglucan galactosyltransferase, MUR3, but is required for galactosyl-substitution of xyloglucan at a different position. The gene was termed XLT2 for Xyloglucan L-side chain galactosylTransferase position 2. It represents an enzyme in the same subclade of glycosyltransferase family 47 as MUR3. A double mutant defective in both MUR3 (mur3.1) and XLT2 led to an Arabidopsis plant with xyloglucan that consists essentially of only xylosylated glucosyl units, with no further substitutions.

Ethnopharmacological relevance Tropaeolum majus L. (Tropaeolaceae) is a medicinal herb popularly used in Brazil for treatment of inflammatory and cardiovascular diseases. Despite some published data on its efficacy, there are still few toxicological data describing the safety of this plant. The aim of this study was to evaluate the (anti)estrogenic and (anti)androgenic activity of the hydroethanolic extract obtained from Tropaeolum majus L. (HETM), as well as its possible effects on uterine contractility. Materials and methods Three experimental protocols were performed, (a) uterotrophic assay, (b) Hershberger assay and (c) an ex vivo test to investigate the effects of maternal administration of HETM on uterine contractility at the end of pregnancy. In all protocols three doses of the HETM were administered to Wistar rats: 3, 30 and 300 mg/kg. Results In vivo tests for detection of (anti)androgenic and (anti)estrogenic activities did not show any significant alterations. Similarly, no alterations were observed on uterine contractility induced by oxytocin and arachidonic acid. Conclusions HETM was unable to produce (anti)estrogenic or (anti)androgenic activities in the short-term in vivo screening assays performed. In addition, there was no evidence that HETM can affect uterine contractility following gestational exposure of rats.

Ethnopharmacological relevance Previous studies have shown that the extracts obtained from Tropaeolum majus L., and its main compound isoquercitrin (ISQ), exhibit pronounced diuretic effects, supporting the ethnopharmacological use of this plant. The aim of this study was to evaluate the efficacy and mechanisms underlying the diuretic action of an ethanolic extract of Tropaeolum majus (HETM), its purified fraction (TMLR), and its main compound ISQ, in spontaneously hypertensive rats (SHR). Materials and methods The diuretic effects of HETM (300 mg/kg; p.o. ), TMLR (100 mg/kg; p.o. ), and ISQ (10 mg/kg; p.o. ), were compared with classical diuretics in 7 days repeated-dose treatment. The urinary volume, sodium, potassium, chloride, bicarbonate, conductivity, pH and density were estimated in the sample collected for 15 h. The plasmatic concentration of sodium, potassium, urea, creatinine, aldosterone, vasopressin, nitrite and angiotensin converting enzyme (ACE) activity were measured in samples collected at the end of the experiment (seventh day). Using pharmacological antagonists or inhibitors, we determine the involvement of bradykinin, prostaglandin and nitric oxide (NO) in ISQ-induced diuresis. In addition, reactive oxygen species (ROS) and the activity of erythrocytary carbonic anhydrase and renal Na + /K + /ATPase were evaluated in vitro . Results HETM, TMLR and ISQ increased diuresis similarly to spironolactone and also presented K + -sparing effects. All groups presented both plasmatic aldosterone levels and ACE activity reduced. Previous treatment with HOE-140 (a B2-bradykinin receptor antagonist), or indomethacin (a cyclooxygenase inhibitor), or L-NAME (a NO synthase inhibitor), fully avoided the diuretic effect of ISQ. In addition, the 7 days treatment with ISQ resulted in increased plasmatic levels of nitrite and reducing ROS production. Moreover, the renal Na + /K + /ATPase activity was significantly decreased by ISQ. Conclusion Our results suggest that the mechanisms through ISQ and extracts of Tropaeolum majus increase diuresis in SHR rats are mainly related to ACE inhibition, increased bioavailability of bradykinin, PGI2, and nitric oxide, besides an inhibitory effect on Na + /K + -ATPase.

Fluorescently labeled derivatives of a xyloglucan (XG) nonasaccharide Glc(4)Xyl(3)Gal(2) (XLLG) were used as glycosyl acceptors in assays of xyloglucan endotransglycosylase (XET) from germinated nasturtium (Tropaeolum majus) seeds. We have investigated how the type of the oligosaccharide label influences the kinetic parameters of the reaction. The fluorescent probes used to label XLLG were anthranilic acid (AA), 8-aminonaphtalene-1,3,6-trisulfonic acid (ANTS), fluorescein isothiocyanate (FITC), and sulforhodamine (SR), respectively. The obtained data were compared with those of the reactions where aldose and/or alditol forms of tritium-labeled xyloglucan-derived nonasaccharide served as the respective acceptors. Modification at C-1 of the reducing-end glucose in XLLG by substitution with the fluorophore markedly affected the kinetic parameters of the reaction. The Michaelis constants K(m) for individual acceptors increased in the order [1-(3)H]XLLGXLLG-SR[1-(3)H]XLLGolXLLG-FITCXLLG-ANTSXLLG-AA, while the turnover numbers characterized by k(cat) decreased in the order XLLG-FITCXLLG-SRXLLG-ANTS[1-(3)H]XLLGol[1-(3)H]XLLGXLLG-AA. Catalytic efficiency (expressed as k(cat)/K(m)) with XLLG labeled with SR or FITC was 15 and 28 times, respectively, higher than with the tritium-labeled natural substrate [1-(3)H]XLLG. Comparison of the kinetic parameters found with acceptors labeled with different types of labels enables to select the most effective substrates for the high-throughput assays of XET.

Psoriasis pathogenesis includes immune activation and oxidative damage. Tropaeolum majus is a plant rich in antioxidant anthocyanins. This study aimed to evaluate the effect of Tropaeolum majus extracts on psoriasis-like wounds. The ethyl acetate, ethanolic and hydroethanolic extracts were obtained by maceration. Their anthocyanins content was determined by differential pH method. Mice were allocated in normal and negative control groups (n=12) treated with 10% glycerol and groups receiving extract (50 mg/mL). Topical treatments were daily (5 days). Later, half of each group was euthanized to collect skin for analyzes of TNF-α, IL-1β, lipid peroxidation, protein carbonylation and reduced glutathione (GSH). The other half was kept to determine the time for wounds’ clearance. Anthocyanins concentration was 0.6 ± 0.1; 6.9 ± 0.9 and 10.9 ± 0.6 mg/g in ethyl acetate, ethanolic and hydroethanolic extracts. Wounds severity was reduced by 35% and up to 45% by the ethanolic and hydroethanolic extracts, as well as the time for clearance. Concentration of TNF-α and IL-1β was normalized by these extracts, along with lipid peroxidation and protein carbonylation. Extracts caused recovery of GSH, mainly the hydroethanolic one. The antipsoriatic activity was associated with antioxidant action.

Five forms of xyloglucan endotransglycosylase/hydrolase (XTH) differing in their isoelectric points (pI) were detected in crude extracts from germinating nasturtium seeds. Without further fractionation, all five forms behaved as typical endotransglycosylases since they exhibited only transglycosylating (XET) activity and no xyloglucan-hydrolysing (XEH) activity. They all were glycoproteins with identical molecular mass, and deglycosylation led to a decrease in molecular mass from approximately 29 to 26.5 kDa. The major enzyme form having pI 6.3, temporarily designated as TmXET(6.3), was isolated and characterized. Molecular and biochemical properties of TmXET(6.3) confirmed its distinction from the XTHs described previously from nasturtium. The enzyme exhibited broad substrate specificity by transferring xyloglucan or hydroxyethylcellulose fragments not only to oligoxyloglucosides and cello-oligosaccharides but also to oligosaccharides derived from beta-(1,4)-d-glucuronoxylan, beta-(1,6)-d-glucan, mixed-linkage beta-(1,3; 1,4)-d-glucan and at a relatively low rate also to beta-(1,3)-gluco-oligosaccharides. The transglycosylating activity with xyloglucan as donor and cello-oligosaccharides as acceptors represented 4.6%, with laminarioligosaccharides 0.23%, with mixed-linkage beta-(1,3; 1,4)-d-gluco-oligosaccharides 2.06%, with beta-(1,4)-d-glucuronoxylo-oligosaccharides 0.31% and with beta-(1,6)-d-gluco-oligosaccharides 0.69% of that determined with xyloglucan oligosaccharides as acceptors. Based on the sequence homology of tryptic fragments with the sequences of known XTHs, the TmXET(6.3) was classified into group II of the XTH phylogeny of glycoside hydrolase family GH16.

Plant surfaces provide a large variety of functional structures. Epicuticular waxes represent the most common multifunctional surface structures existing in plants. Their ability to self-assemble into nanostructures has been studied. Artificial surfaces covered with wax nanotubules have been developed. Thermal evaporation has been used to deposit waxes, isolated from the leaves of Tropaeolum majus (Nasturtium), on artificial substrates. The thermal evaporation of multi-component T. majus wax combined with specimen storage at 50 °C led to homogeneously covered artificial surfaces with superhydrophobic properties and low hysteresis. Fabricated structures and surface chemistry mimic the superhydrophobic surfaces of T. majus leaves. It has been demonstrated that superhydrophobicity and low hysteresis are connected to the nanostructure formed by hydrophobic wax tubules. The developed method for surface coating is based on self-assembly of multi-component waxes and results in a homogeneous coating of artificial surfaces with three-dimensional wax tubules.

The diamondback moth, Plutella xylostella (L.) is considered a specialist on Brassicaceae, but it is capable of expanding its food range by incorporation of non-brassicaceous plants into its diet. The use of a new food plant may change food availability and vulnerability of P. xylostella to its natural enemies, especially specialist parasitoids. In this laboratory study, we evaluated the bottom-up effects of two Brassicaceae viz. Brassica napus L. and Descurainia sophia (L.) Webb ex Prantl and two non-Brassicaceae viz. Tropaeolum majus L. and Cleome hassleriana Chodat on several fitness correlates of the specialist parasitoid, Diadegma insulare (Cresson) reared on P. xylostella larvae. Percentage of parasitism of host larvae by D. insulare varied among the plant species and was highest on T. majus and lowest on D. sophia. Values of several fitness correlates for D. insulare differed when the host was feeding on various plant species. Egg to adult development was fastest on B. napus followed by C. hassleriana, D. sophia and T. majus. Female wasps reared on C. hasseleriana lived the longest in absence of food. The response of D. insulare to potential food-plant expansion by its host P. xylostella is discussed.

Major anthocyanins, ascorbic acid content, total phenolic content, and the radical scavenging activity against ABTS and DPPH radicals in petals of orange Nasturtium flowers ( Tropaeolum majus ), were investigated. Anthocyanin (ACN) content in the petals was 72 mg/100 g FW and pelargonidin 3-sophoroside represented 91% of the total ACN content. The ascorbic acid content was 71.5 mg/100 g and the total phenolic content as determined by the Folin–Ciocalteau method was 406 mg GAE/100 g FW. The radical scavenging activities against ABTS and DPPH radicals were 458 and 91.87 μm trolox eq/g FW, respectively. The excellent free radical scavenging activities along with high phenolic and ascorbic acid content of Nasturtium flowers suggest that they could be source of natural pigments and antioxidants for applications in functional foods.

Tropaeolum majus L. (Tropaeolaceae), popularly known as “chaguinha”, is well recognized in Brazilian traditional medicine as diuretic agent, although no scientific data have been published to support this effect. Aim of the study To evaluate the diuretic activity of the infusion and the hydroethanolic extract (HETM) of Tropaeolum majus , and possible mechanism of action. Material and methods The infusions (2,5 – 10%) and the HETM doses (150, 300 mg/kg) were orally administered to rats. Urinary excretion, the electrolytes levels, and urea and creatinine were measured in of saline-loaded rats. Results The oral administration of 10% (corresponding to 500 mg/kg) of the infusion increased significantly the urinary Na + excretion. Only the oral administration of 300 mg/kg of HETM increased significantly the urinary and Na + excretion. Prolonged administration of the HETM (300 mg/kg) significantly increased diuresis and the urinary excretion of Na + , but others parameters were unaffected. To gain some evidence in possible involvement of prostaglandins system in diuretic action, the oral administration of HETM (300 mg/kg) in association indomethacin (5 mg/kg) reduced the urinary and sodium excretion when compared only HETM group. Conclusion The results suggest that HETM could present compound(s) responsible for diuretic activities with no signs of toxicity, and the mechanism could involve prostaglandin system.

Glucotropaeolin and total phenolic concentrations were assessed in three different organs (inflorescences, leaves, unripe seeds) of nasturtium ( Tropaeolum majus L.), which are consumed as herbal plant products, in order to determine the effect of short-term and moderate UV-B exposure as targeted postharvest stress treatment on the secondary plant metabolism. For this purpose, nasturtium plants were subjected to two UV-B radiation levels: 0.075 and 0.15 W h m − 2 . The results clearly demonstrate that the plant response to short-term and moderate UV-B exposure is organ-, plant tissue age-, and phytochemical-specific and that these factors influence a change of secondary metabolism as revealed by the different phytochemical concentration levels elicited. Industrial relevance In food processing UV treatment is mainly attributed to disinfection. This study examined the feasibility of short-term and moderate UV-B application as emerging technology for enhancing health-promoting phytochemicals in freshly consumed plant products (inflorescences, leaves, unripe seeds) demonstrated by the herbal plant nasturtium. Optimizing phytochemical concentration by targeted postharvest UV-B applications will add health value and subsequently generate new opportunities for growers and processors by achieving the health-oriented food market.

Using a degenerate primers approach, a cDNA of a putative microsomal fatty acid desaturase showing high homology to other plant microsomal FAD2 (Δ12) desaturases was obtained from Tropaeolum majus. This cDNA contains an open reading frame of 1152 bp encoding a protein of 383 amino acids. Expression of the T. majus FAD2 oleate-Δ12 desaturase homolog in yeast cells resulted in accumulation of an appreciable amount of cis-9,12-hexadecadienoic (16:2Δ9,12) and linoleic acid (18:2Δ9,12), fatty acids not normally present in wild type yeast, indicating that the gene encodes a functional FAD2 enzyme. Genetic analyses showed that the T. majus FAD2 is represented by at least one constitutively expressed gene. Transformation of a low linoleic (18:2Δ9,12) Arabidopsis mutant line (AL63) with the T. majus FAD2 cDNA restored oleate-Δ12 desaturase activity and wild type proportions of linoleate in the seed oils of the transgenic plants.

Changes of cuticular wax morphology, chemistry, and wettability of Brassica oleracea (Brassicaceae), Eucalyptus gunnii (Myrtaceae) and Tropaeolum majus (Tropaeolaceae), with different types of surface waxes, cultivated at three levels of relative air humidities (RH) (a: 20–30%, b: 40–75% and c: 98% RH) have been investigated. Wax chemistry was investigated by gas chromatography (GC) and mass spectroscopy (MS), micro morphology by scanning electron microscopy (SEM) and surface wettability by measuring the contact angle. Grown at 98% RH, all species showed decreased total wax mass and wax crystal density but significantly increased leaf surface wettability. In contrast cultivation at 20–30% RH led to increased total amounts of wax and reduced surface wettability. SEM investigations and GC/MS analysis revealed that wax crystal morphology and qualitative wax composition of Brassica were altered after cultivation at 98% RH, whereas chemical composition and morphology of wax crystals in Tropaeolum and Eucalyptus remained unchanged.

Using combinations of different polysaccharides as glycosyl donors and of oligosaccharides fluorescently labeled by sulforhodamine (SR) as glycosyl acceptors, we screened for the presence of transglycosylating activities in extracts from nasturtium (Tropaeolum majus). Besides xyloglucan endotransglycosylase/hydrolase (XTH/XET, EC 2.4.1.207) activity, which transfers xyloglucanosyl residues from xyloglucan (XG) to XG-derived oligosaccharides (XGOs), a glycosyl transfer from XG to SR-labeled cellooligosaccharides and laminarioligosaccharides has been detected. The XGOs also served as acceptors for the glycosyl transfer from soluble cellulose derivatives carboxymethyl cellulose and hydroxyethylcellulose. The effectivity of these polysaccharides as glycosyl donors for transfer to XG-derived octasaccharide [1-3H]XXLGol decreased in the order XG > HEC > CMC. Isoelectric focusing in polyacrylamide gels showed that bands corresponding to hetero-transglycosylase activities coincided with zones corresponding to XTH/XET. These results can be explained as due either to substrate non-specificity of certain isoenzymes of XTH/XET or to existence of enzymes catalyzing a hetero-transfer, that is the formation of covalent linkages between different types of carbohydrate polymers.

Two isoenzymes of xyloglucan endo-transglycosylase (XET, EC 2.4.1.207) were identified in nasturtium (Tropaeolum majus L.), so far. One is located in seeds (sXET) and is expressed during germination. The other enzyme (eXET) is confined to epicotyls and other growing regions. In this work, we examined catalytic properties of the two XETs and tried to find a correlation with their presumed functions. The two enzymes had similar isoelectric points at about pH 6.5 but had different pH-activity profiles and differed in Km values for xyloglucan-derived oligosaccharides (XGOS) as acceptor substrates. Moreover, they showed clearly distinct preferences in selecting the site of attack on xyloglucan (XG) molecules. While sXET selected the site of cleavage on XG molecules stochastically along the length of their polyglucose main chain and preferred low-molecular mass (MM) XGOS as glycosyl acceptors, eXET attacked the substrate molecule predominantly near the reducing end and showed no preference as to the size of XGOS acceptors. These properties corroborate well with the proposed functions of the two isoenzymes: the sXET plays a role in degrading XG reserves in seeds during germination, whereas the eXET is engaged in cell wall rearrangement and integration of new XG molecules into the preexisting cell wall structure during growth.

Five species of edible flowers were stored in polyethylene bags at −2.5 to 20 °C. Flowers were rated for visual quality each day for 2 weeks on a scale of 1–5 (5 being the highest quality). Viola tricolor L. ‘Helen Mount’ (viola), V. ×wittrockiana L. ‘Accord Banner Clear Mixture’ (pansy), and Tropaeolum majus L. ‘Jewel Mix’ (nasturtium) flowers showed similar losses in quality and were all rated a 5 when stored at 0 and 2.5 °C after 2 weeks. Borago officinalis L. (borage) stored at 0–5 °C were marketable, rated a 3 or higher, after 1 week, and those stored at −2.5 °C were still marketable after 2 weeks. Phaseolus coccineus L. ‘Dwarf Bees’ (scarlet runner bean) flowers when stored at 0–10 °C were still marketable after 1 week, but were unmarketable after 2 weeks, at any temperature.

Six partial cDNAs for cell wall degradation-related enzymes, xyloglucan endo-transglycosylase (XET), polygalacturonase (PG), pectin methylesterase (PME), pectate lyase (PL), cellulase (Cel), and β- d -galactosidase (GAL), were isolated from a veraison-specific subtractive library made from Kyoho grape (Vitis labruscana) berries. During the development of Kyoho grape berries, the expression of these genes was analyzed. Among the genes analyzed, XET gene expression was closely related to berry softening; slight XET gene expression was detected before veraison and was markedly increased at veraison (the stage of the onset of berry softening). In addition, the expression of the gene was berry specific. In the other genes, except for PL, however, no expression was detected during the berry development; PL was detected only after the coloring stage began. These observations suggest that XET plays an important role in grape berry softening. To obtain further information about this gene, a full-length cDNA clone (VXET 1) encoding XET was isolated from a cDNA library of Kyoho grape berries and characterized. The VXET 1 was 1326 bp in length and contained a 5′-untranslated region of 67 bp, an open reading frame of 873 bp, and a 3′-untranslated region of 386 bp. The deduced amino acid sequence of the VXET 1 showed 73.5% identity with the corresponding XET (NXG 1) from nasturtium (Tropaeolum majus) that has been shown to have endo-glucanase activity. These findings suggest that the VXET 1 product cleaves a cellulose–xyloglucan network of cell wall and induces the softening of Kyoho grape berries at veraison.

Summary The plant signal compounds jasmonic acid or salicylic acid were applied as abiotic elicitors to leaves of glucosinolate-containing members of the Tropaeolaceae (Tropaeolum majus) and Caricaceae (Carica papaya) and to leaves of the glucosinolate-free plant cucumber. Both compounds are known to induce the accumulation of glucosinolates in Brassica plants. In roots of glucosinolate-containing plants the two compounds enhanced glucosinolate levels or new glucosinolates were accumulated. In all plants treated with jasmonic acid a reduction of root colonization by the arbuscular mycorrhizal fungus Glomus mosseae was observed. No such effect occurred after the salicylic acid treatment. In addition, members of the glucosinolate-containing Tropaeolaceae family were inoculated with the arbuscular mycorrhizal fungus (AMF), and later on the glucosinolate content was determined in roots of mycorrhizal and in roots of non-mycorrhizal plants. Root colonization by the AMF resulted in a large increase of the glucosinolate content, however, the glucosinolate levels in mycorrhizal and in non-mycorrhizal plants showed no effect on root colonization by the AMF. From our results we concluded that the glucosinolate levels can not generally be linked to the nonhost status of glucosinolate-containing plants, however, a role of specific glucosinolates in the expression of the non-host status of glucosinolate-containing plants can not be excluded. Moreover, we found that the application of jasmonic acid highly suppresses mycorrhization and this suppression is not a glucosinolate-dependent mechanism.

A chromogenic bioassay was utilized to determine the antithrombin activity of methylene chloride and methanol extracts prepared from 50 plants of Azores. Extracts of the six plants Hedychium gardneranum, Tropaeolum majus, Gunnera tinctoria, Hedera helix, Festuca jubata and Laurus azorica demonstrated activity of 78% or higher in this bioassay system.

Amino acid residues involved at the active site of Tropaeolum majus invertase (β- d -fructofuranoside fructohydrolase, EC 3.2.1.26) were determined. Photo-oxidation and Woodward's reagent K revealed the presence of histidyl and carboxylic groups at the active site of the enzyme. These groups were protected by sucrose and trehalose but not by fructose. Thiol groups were determined with sodium p -chloromercuribenzoate and with 5,5′-dithio- bis (2-nitrobenzoic acid). These groups were protected by fructose and to a lesser degree by sucrose, but were not protected by trehalose. The pH dependence of V max and K m at 27° and 37° is consistent with the presence of carboxyl and histidyl residues at the invertase active site. The p K a values obtained correspond to ionization heats of 1700 cal mol −1 and 6820 cal mol −1 . The results were consistent with the presence of imidazole, carboxylic and thiol groups at the active site.

A new cDNA clone ( AtXTR8 ) encoding a xyloglucan endo -transglycosylase (XET)-related protein was isolated from an Arabidopsis thaliana germinating seed cDNA library, using a differential screen. The predicted amino acid sequence displays only 38 to 42% amino acid identity with other members of the Arabidopsis XTR (XET-related) protein family but shows 64% identity to a xyloglucan endo -transglycosylase enzyme (TmNXG1) expressed in nasturtium ( Tropaeolum majus ) germinating seeds. The AtXTR8 transcipts are expressed in germinating seeds as early as 24 h after imbibition with highest level of accumulation reached at about 72 h. In adult plants, transcripts are mainly detected in roots and to a lower extent in inflorescence stems. During imbibition of the severely gibberellin-deficient gal-3 mutant seeds, transcripts are detected only if exogenous gibberellins are supplied in the medium. suggesting that gibberellins are directly or indirectly required for AtXTR8 gene expression. Unlike other XET genes such as TCH4, EXT and XTR3 which are rapidly activated by auxins in wild type Arabidopsis , the steady state level of AtXTR8 transcripts is not markedly increased by auxin treatment of 6-day-old seedlings. Phylogenetic analysis confirms that the XET and XTR protein sequences so far identified in various plant species split in three groups and Arabidopsis AtXTR8, which enzymatic activity has not been assessed, belongs to the least related group III.

Friable calli, obtained from Tropaeolum majus leaves, on Gamborg B5 medium supplemented with 2,4-D, kinetin and casein amino acids, were used for the establishment of cell suspension cultures in the same liquid medium. Different basal media, inoculum densities, sucrose concentrations, nitrogen sources and cysteine levels were assayed for biomass production. The best growth rates were achieved in Gamborg B5 medium supplemented with 1·5 mg litre −1 2,4-dichlorophenoxyacetic acid, 0·1 mg litre −1 kinetin, 2 g litre −1 casein amino acids, 100 mg litre −1 cysteine and with an initial inoculum of 50 g (fresh weight) litre −1 . The doubling time obtained under these conditions was about 55 h.

[14C]Fucose-labelled xyloglucan (XG) was synthesized from tamarind seed XG by incubating it with GDP-[14C]fucose plus solubilized pea fucosyltransferase, and [14C]fucose-labelled XG nonasaccharide was prepared from the parent hemicellulose by partial hydrolysis with fungal cellulase. alpha-L-Fucosidase activity was readily detected in crude enzyme extracts of growing regions of etiolated pea stems (Pisum sativum) and in cotyledons of germinating nasturtium seedlings (Tropaeolum majus) using the fucosylated XG-nonasaccharide as substrate. Both enzymes showed little activity against intact fucosylated XG and they were totally inactive against p-nitrophenyl-alpha-L-fucoside. Auxin treatment of pea stems, which greatly increased the activity of endo-1,4-beta-glucanases that hydrolyse XG in apical growing regions, failed to result in a similar increase in XG-nonasaccharide alpha-fucosidase activity. However, germination of nasturtium seed, which resulted in a large increase in endo-1,4-beta-glucanase (XG-ase) activity in the cotyledons, was accompanied by comparable increases in XG-alpha-fucosidase activity.

Summary The influence of abscisic acid (ABA) and t cinnamic acid, individually and in combination, on senescence of excised nasturtium ( Tropaeolum majus ) leaves as related to stomatal movements has been studied. ABA (10 ∔5 M) induced an acceleration of chlorophyll loss in dark that was accompanied by an increase in stomatal diffusive resistance (SDR) of leaves. Trans-cinnamic acid (tCA) prevented the ABA-induced loss of chlorophyll and there was a proportionate decrease in SDR. When applied alone tCA, in general, delayed the chlorophyll loss SDR being slightly lower at 10 ∔5 M than in control. tCA treatment resulted in a massive release of potassium ions from senescing leaves. Significance of the findings is discussed.

Summary The suspensor of the nasturtium, Tropaeolum majus L., is a several millimeter large, tripartite embryonic organ. The giant cells of the embryo-suspending thread (“embryo-suspensor”) are connected to the embryo with plasmodesmata. Their ultrastructure gradually changes from the apical pole to the basal cell mass. All cells, however, display large nuclei and nucleoli, and deep cytoplasmic invaginations. The intermediate suspensor cells contain many ribosomes and polysomes, indicating synthetic activity, while the basal ones develop wall ingrowths which are suggestive of transfer of nutritive material from the carpel to the embryo.

The lipid contents of callus cultures of rape ( Brassica napus ) and nasturtium ( Tropaeolum majus ) increase in response to decreasing the temperature, though to different degree. Irrespective of the incubation temperature the lipids in cultures of both plants contain as predominant classes steryl glycosides, esterified steryl glycosides, sterols, steryl esters and fatty acids and, as minor constituents, various proportions of triacylglycerols, phospholipids and several unidentified fractions. The ratio of phospholipids to triacylglycerols as well as the ratio of diacylglycerophosphorylethanolamines to dicylglycerophosphorylcholines increase with time both in rape cultures incubated at 30°C and in those kept at 5°C. The lipids in rape and nasturtium cultures grown at 30°C contain smaller proportions of polyunsaturated fatty acids than the lipids in cultures incubated at 5°C. Erucic acid, the major constituent fatty acid of the seed lipids, in both plants, occurs only in trace amounts in the lipids of callus cultures. In contrast, linoleic and linolenic acids, which occur only in traces in the seed lipids of nasturtium, are major constituent fatty acids in the lipids of callus cultures derived from seedlings of this plant. The levels of constituent polyunsaturated fatty acids in the diacylglycerophosphorylethanolamines and the diacylglycerophosphorylcholines increase with time whereas in the triacylglycerols only linolenic acid is slightly increased.

The invertase of Tropaeolum majus leaves was partially purified. Its optimum pH was ca 5.25 and its Km values for sucrose, raffinose, and stachyose were 5.3, 17 and 25 mM respectively. The products of the reaction were in vitro inhibitors of the enzyme. Fructose was a partial competitive inhibitor (K1, 49 mM) and glucose was a non- competitive classical inhibitor (K1, 57 mM). Proteins were activators of the enzyme. As activation by proteins suppressed the inhibitory effects of the reaction products, product inhibition does not appear to be involved in the physiological regulation of the enzyme.

beta-D-Galactosidase activity has been detected previously in the cotyledons of germinated nasturtium (Tropaeolum majus L.) seeds and has been linked to the hydrolysis in vivo of storage xyloglucan (amyloid) (Edwards, M., Dea, I. C. M., Bulpin, P. V., and Reid, J. S. G. (1985) Planta (Berl.) 163, 133-140). The major beta-D-galactosidase present in extracts from the cotyledons of 9-day seedlings has now been purified to apparent homogeneity. The enzyme (Mr 97,000, no subunits) comprised a range of closely related molecular species ranging in isoelectric point from pH 6.6 to 7.1. Further purification to give a single protein band on isoelectric focusing (pI = 7.1) was achieved by chromatofocusing. The pH optimum of the enzyme (mixed molecular species) was 4.0-5.0 (stable from pH 3-10), and the temperature optimum was 50 degrees C (stable to 50 degrees C). It hydrolyzed lactose and beta-D-galactopyranosides but not melibiose and alpha-D-galactopyranosides. It did not release the terminal nonreducing alpha-D-galactopyranosyl residues from seed galactomannans, but catalyzed the rapid removal of terminal nonreducing beta-D-galactopyranosyl residues from xyloglucans. On the basis of the ability of the enzyme to hydrolyze xyloglucans, the kinetics of xyloglucan hydrolysis, and an experimental demonstration of a clear correlation between xyloglucan depletion and the activity in vitro of this enzyme, it is argued that the cell-wall storage xyloglucan of the nasturtium seed is its natural substrate.

Summary The role of pentose phosphate pathway has been examined in the embryo suspensor of Tropaeolum majus . Quantitative cytochemical data on glucose-6-phosphate dehydrogenase and C 6 /C 1 ratio revealed very high level of pentose phosphate pathway in the suspensor cells of early embryo. The role of pentose phosphate pathway in providing pentose sugars for nucleic acid biosynthesis and reducing power (NADPH) etc. for the biosynthetic reductions in relation to the suspensor is discussed.

Summary The embryo, suspensor and suspensor haustorium of Tropaeolum majus were analysed separately for cellular content, protein content and cellular rates of synthesis of RNA and proteins. The pattern of synthesis differed in suspensor and the haustorium at all stages of embryo development: values for the suspensor were higher than the embryo. The observed data are correlated with the functions of suspensor.

Summary The pattern of dark carbon dioxide fixation in embryos, suspensors and haustoria of Tropaeolum majus in different stages of development (globular, heart and cotyledonary) is studied. A comparison is also made between PEP-carboxylase activity and 14CO2 incorporation in embryo, suspensor and haustoria. Phosphoenol-pyruvate carboxylase activity is correlated with the faculty of the young embryos (globular and heart-shaped) and its suspensor cells to fix CO2 by non-photosynthetic mechanisms. The present data provide biochemical evidence in characterizing physiological function of the suspensor in early embryogenesis (synthesis and transfer). Haustoria possibly acted as “transfer cells”.

Endo-(1----4)-beta-D-glucanase activity has previously been detected in the cotyledons of germinated nasturtium (Tropaeolum majus L.) seeds, and has been linked to the hydrolysis in vivo of storage xyloglucan (amyloid) (Edwards, M., Dea, I. C. M., Bulpin, P. V., and Reid, J. S. G. (1985) Planta (Berl.) 163, 133-140). Extracts from the cotyledons of 14-day seedlings are now shown to contain a single endo-glucanase activity, and it has been purified to apparent homogeneity by sequential anion-exchange chromatography, cation-exchange chromatography, and gel filtration. The purified enzyme gave a single protein band on polyacrylamide gel electrophoresis, dodecyl sulfate gel electrophoresis, and isoelectric focusing. The isoelectric point was 5.0, the pH optimum 4.5-5.0, and the temperature optimum 40 degrees C. Dodecyl sulfate electrophoresis gave a molecular weight of 29,000; permeation methods gave lower values. The enzyme contained about 5% carbohydrate. An endo mode of action on tamarind seed xyloglucan was deduced by monitoring solution viscosity and reducing power, and by analyzing the end products of the reaction. The specificity of the enzyme toward a wide range of substrates, including celluloses, carboxymethyl and hydroxyethyl celluloses, glucomannan, galactoglucomannans, mixed-linkage (1----3 and 1----4)-beta-D-glucan, laminarin, and xyloglucans from seeds and primary cell walls, was tested. Only the xyloglucans were hydrolyzed. It is concluded that the enzyme is a pure, endo-acting (1----4)-beta-D-glucanase which is novel in its apparently complete specificity toward xyloglucans. It is speculated that enzymes of this type may have escaped earlier detection because it is normal practice to screen for endo-(1----4)-beta-D-glucanase using artificial cellulose derivatives and that they may be widely involved in xyloglucan metabolism in plant cell walls.

Early embryogenesis in the nasturtium, Tropaeolum majus , is characterized by the development of a suspensor several times larger than the embryo proper. Scanning densitometric determination of the nuclear DNA (Feulgen) contents at the stage of a globular embryo revealed the existence of diploid nuclei (2C = 2.66 pg) only in the cells of the embryo proper, while all nuclei of the suspensor were endopolyploid (up to 2048C, i.e. 5447.68 pg). The majority of the nuclei display polytene chromosomes in the diploid number (2n = 28). Several elongated suspensor cells show, however, nuclei deficient in heterochromatin; the DNA content of these nuclei is relatively low and does not fit the geometrical order of the endopolyploidy classes. Both nuclear structure and DNA content thus indicate DNA (heterochromatin) underreplication to occur in certain cells of the suspensor.

Summary Influence of cytokinins and other growth substances on translocation of some plant compounds in detached leaves An investigation was carried out to study the influence of cytokinins and some growth substances on senescence and translocation processes in detached leaves of Tropaeolum majus L. (and tobacco). The leaves were stored under humid conditions in the dark Kinetin, benzyladenine (BA), zeatin and gibberellic acid (GA3) (10 — 30 mg/l) applied on the whole leaf-blade (leaves without petiole) delayed the decomposition of chlorophyll and protein to about the same extent. The decomposition of carbohydrates was unaffected. Application of kinetin to one half of cut leaf-blades caused a translocation of carbohydrates, N- and P-compounds, and K-ions (or of Rb after treatment with labelled Rb) from the untreated to the treated leaf part. Ca and Na were not translocated. In some cases soluble N was accumulated on the place of treatment in spite of a netto-decomposition of protein. BA and zeatin were almost as effective as kinetin. It seems that cytokinins affect by „retention” or “attraction” all those mineral elements, from which a good mobility for retranslocation is known. GA had no effect on the translocation of the compounds mentioned, probably because of their migration to the untreated area also In cut leaves with petioles carbohydrates, N- and P-compounds and K-ions moved from the blades to the petioles. Following this a new synthesis of protein and carbohydrates in the petiole occured. Treatment of the leaf blade with cytokinins and GA diminished this translocation considerably. IAA however increased the downward stream. It is assumed that the absorbed IAA migrated downward into the petiole in the same way as auxin normally does in cut leaves, and therefore the accumulation in the petiole (“sink”) was increased. Uptake of GA and zeatin via the cut petiole delayed senescence as application on the leaf blade did, that is, over the whole leaf blade. In the case of kinetin and BA, however, the leaves remained green only in the area near the connection of leaf and petiole. This shows that the growth substances spread out in the leaf blade to a different extent The results obtained with kinetin on leaves from Tropaeolum were confirmed not only by detached leaves of tobacco but also by tobacco leaves still attached on plants.

An enzyme which catalyses the formation of desulfobenzylglucosinolate by glucosyl transfer from UDP glucose to phenylacetothiohydroximate has been isolated from leaves of Tropaeolum majus L. and purified 20-fold. The enzyme possessed a high degree of specificity for the sugar acceptor molecule (thiohydroximates), the donor nucleotide (UPD) and its sugar (glucose). The activity of the enzyme was increased by sulfhydryl, chelating and reducing compounds: the activity disappeared in the absence of β-mercaptoethanol and was strongly inhibited by mercuric chloride and p -chloromercuribenzoate. Cell-free extracts of other glucosinolate-containing plants, including Sinapis alba L., Nasturtium officinale R. Br. and Armoracia lapathifolia Gilib. contained a similar glucosyl-transferase activity. It is concluded that the glycosylation of phenylacetothiohydroximate is an integral step in the biosynthesis of benzylglucosinolate.

Results have been obtained consistent with the hypothesis that aci tautomers of nitro compounds are precursors of glucosinolates. When dl -[3-14C]phenylalanine and [14C]1-nitro-2-phenylethane were fed to shoots of Tropaeolum majus L., the incorporation of tracer from each compound into benzylglucosinolate was found to be similar. Conversion of 14C from 1-nitro-2-phenylethane into the aglycone moiety of benzyl-glucosinolate was specific. The natural occurrence of 1-nitro-2-phenylethane in T. majus and its formation in this plant from [1-14C]phenylacetaldoxime were demonstrated by gas chromatography and by means of a trapping experiment.

A number of glycosidases have been qualitatively identified in the seeds of Tropaeolum majus , the common nasturtium. A thioglucosidase, a β-glucosidase, a fructofuranosidase, and an enzyme causing partial hydrolysis of amylopectin and glycogen, have been isolated and partially purified. Hydrolytic activity also indicated the presence of an α-1,1-glucosidase and possibly the presence of a β-galactosidase, although the latter was not separated from β-glucosidase activity. The enzyme responsible for the hydrolysis of the polysaccharides was obtained as a crystalline protein, but the exact nature of the hydrolytic activity has not yet been determined.

The effects of sucrose irradiated with 0·5 to 3 Mrad of γ-rays and stored for different durations were studied in Tropaeolum majus, using the germination and tube growth of pollen as indices. The extent of the inhibitory effect increased with dosage and was either enhanced or reduced with storage depending upon the initial dose. It appears possible that the radiolytic products of sucrose formed at different dosages may be qualitatively different.

Summary A recently developed microtechnique ( Donike and Przybyllok , 1977) allowed the determination of auxin (IAA) concentrations in small tissue samples of early embryos of Tropaeolum . The suspensor, an embryonal haustorium-like organ, yielded significantly higher IAA amounts than the embryo proper. This finding confirms earlier suggestions on the possible functions of the suspensor in the nourishment of the embryo and the control of its development.

Summary The influence of atmospheric CO2 concentration on senescence of detached leaves of two C3 plants (Avena sativa, Tropaeolum majus) and one C4 plant (Zea mays) in light was studied. Leaf senescence was enhanced in CO2-free air only in leaves of oat and nasturtium. This seems to support the possibility that products of photorespiration are involved in senescence processes. The role of photorespiratory products in senescence is discussed, especially under consideration of plant adaptation to stress conditions like drought, salinity and high temperature.

(Z)-11-Eicosenoic (gondoic) and (Z)-13-docosenoic (erucic) acids were found in large proportions as constituent fatty acids of the triglycerides and polar lipids in seeds and petals of Tropaeolum majus. In the lipids of the other floral organs as well as in those of vegetative organs, only traces of these fatty acids were detected. During seed germination, the proportions of the two fatty acids did not change. (Z)-9,12- Octadecadienoic (linoleic) and (Z)-9,12,15-octadecatrienoic (linolenic) acids, which occurred only in traces in lipids of the seeds, were major constituent fatty acids of lipids in floral and vegetative organs as well as those of callus cultures.

Embryos and suspensors of Tropaeolum majus at the same stages of seed development were analysed for gibberellins by GC-MS. GA 63 was the only gibberellin present in both tissues. The amount of GA 63 in the suspensor is higher than in the embryo.