Radish Seeds Research Articles

Germination and growth inhibitory sesquiterpene lactones and a flavone from Tithonia diversifolia

Inhibitory effects of two sesquiterpene lactones tagitinin A, tagitinin C and a flavonoid hispidulin isolated from Tithonia diversifolia were determined on germination of radish, cucumber and onion seeds. The flavonoid hispidulin was more toxic to the crop seeds tested and the activity of tagitinin C was weaker than that of tagitinin A and hispidulin. Seventeen derivatives have been prepared from tagitinin A and C by chemical transformation and their phytotoxicity has been compared with the parent compounds (all at 250,μM) using radish seeds. The structural requirements related to their biological activity have also been delineated.

A growth inhibitory factor from lambsquarters (Chenopodium album)

Aqueous extract of air-dried lambsquarters (Chenopodium album) at 25 mg/ml significantly inhibited germination and growth of radish and wheat seeds. Soybean seed germination was not inhibited; however, hypocotyl growth was significantly reduced. Germination of radish seeds in sand amended with pulverized lambsquarters shoots at 2 and 4 mg/g was reduced 40 and 95%, respectively. Shoot dry weight and plant height were also reduced 30 and 9%, respectively, at 4 mg/g, but not at 2 mg/g concentration. Residues after extraction with water incorporated in sand were not inhibitory, indicating water solubility of the inhibitor(s). Aqueous extract of shoots decomposed for five days lost nearly 40% of its inhibitory effect; 20% of it still persisted in the extract of shoots decomposed for 30 days. The filtrate from ultrafiltration of aqueous extract through a pad of molecular-weight cutoff 1000 inhibited radish seeds germination and growth, indicating that the molecular weight of the inhibitor(s) was less than 1000. Partitioning of the aqueous extract by a series of solvents resulted in isolation of an inhibitor(s) in the butanol fraction. Seven phenolics were identified in this fraction using high-performance liquid chromatography (HPLC). Paper chromatographic analysis of the butanol fraction revealed six bands, of which one band withR f =0.83 inhibited germination and growth of radish seeds. Chlorogenic acid identified by HPLC appeared to be the principal component of the phytotoxin.

Hydrophilic foams containing corn products for horticultural use

AbstractPolyurethane foams containing equal amounts of commercial unmodified cornstarch and a polyisocyanate‐terminated polyether exhibit properties suitable for horticultural applications. The use of cornstarch in the foam formulation increased the volume by one‐fourth as compared to the foam without cornstarch. This volume increase represents an economic advantage of 20% savings based on material cost. When cornstarch or corn flour is added to the foam formulation, the foams are more resistant to compressive force. Upon wetting and draining, the foams prepared with no auxiliary blowing agent and containing corn products exhibit higher volumes than do the unfilled foams. Radish seeds planted inside 25 mm cubes of foams began to sprout after 1 day. Early developmental growth for the plants was similar in the control and cornstarch‐filled foams. Spectroscopic analyses of the starch‐containing foams revealed that 60–70% of the cornstarch was metabolized within 4–5 weeks by a microbial consortium. Control polyurethane foams were not affected by the microorganisms tested. © 1994 John Wiley & Sons, Inc.This article is a U.S. Government work and, as such, is in the public domain in the United States of America.

Purification and characterization of napin-like proteins from radish

Nine 2S albumin proteins from garden and sea radish seeds (Raphanus sativus and Raphanus raphanistrum n respectively) have been purified. Their molecular weights and amino acid compositions have been determined. Most of these proteins exhibit a molecular mass of 14.5 kDa, but one component of each species shows a slightly higher value (15.1 kDa). The amino acid compositions obtained are typical of napin-like proteins, although a different content of Tyr and basic residues was observed. The isolated proteins present circular dichroism and fluorescence spectra nearly iderbtical to each other, but different from those of rapeseed or mustard napins. The 2S albumins from radish exhibit about 53% α-helix, 14% β-bend, 16% β-turn and 17% aperiodic conformation

磁場中への周期的暴露がハツカダイコン種子の発芽と生育に及ぼす影響

磁場中への周期的暴露がハツカダイコン種子の発芽と生育に及ぼす影響

発芽および生長中におけるかいわれ大根種子の脂質の変化について

発芽および生長中におけるかいわれ大根種子の脂質の変化について

Response of seedlings of radish (Raphanus sativus) to osmotic shock and external hydrostatic pressure

The effects of an osmotic shock (300 mM mannitol, –0. 67 MPa) or/and increased external hydrostatic pressure on seedlings (42‐h‐germinated seeds) of radish (Raphanus sativus L. cv. Tondo Rosso Quarantino) were investigated. The osmotic shock did not inhibit H+ extrusion and net K‐ uptake, and did not affect the levels of malic acid, reducing sugars, sucrose or amino acids or of the energy charge (i. e. the synthesis of energy‐rich phosphate bonds), but inhibited the synthesis of proteins. RNA and DNA, measured as incorporation of labelled precursors. When the osmotic shock was applied together with an increased external hydrostatic pressure of the same magnitude (+0. 67 MPa), the same metabolic parameters and the inhibition of synthesis of RNA and DNA were not substantially affected, while the inhibition of protein synthesis was practically reversed and the energy charge decreased; the recovery of protein synthesis was not due to a change in labelled leucine uptake capability. Increased external hydrostatic pressure alone decreased the energy charge without affecting the other parameters considered.The possibility that protein synthesis activity is directly controlled by cell turgor pressure (internal hydrostatic pressure) is discussed.

Purification and Sequencing of Radish Seed Calmodulin Antagonists Phosphorylated by Calcium-Dependent Protein Kinase

A family of radish (Raphanus sativus) calmodulin antagonists (RCAs) was purified from seeds by extraction, centrifugation, batch-wise elution from carboxymethyl-cellulose, and high performance liquid chromatography (HPLC) on an SP5PW cation-exchange column. This RCA fraction was further resolved into three calmodulin antagonist polypeptides (RCA1, RCA2, and RCA3) by denaturation in the presence of guanidinium HCl and mercaptoethanol and subsequent reverse-phase HPLC on a C8 column eluted with an acetonitrile gradient in the presence of 0.1% trifluoroacetic acid. The RCA preparation, RCA1, RCA2, RCA3, and other radish seed proteins are phosphorylated by wheat embryo Ca(2+)-dependent protein kinase (CDPK). The RCA preparation contains other CDPK substrates in addition to RCA1, RCA2, and RCA3. The RCA preparation, RCA1, RCA2, and RCA3 inhibit chicken gizzard calmodulin-dependent myosin light chain kinase assayed with a myosin-light chain-based synthetic peptide substrate (fifty percent inhibitory concentrations of RCA2 and RCA3 are about 7 and 2 microM, respectively). N-terminal sequencing by sequential Edman degradation of RCA1, RCA2, and RCA3 revealed sequences having a high homology with the small subunit of the storage protein napin from Brassica napus and with related proteins. The deduced amino acid sequences of RCA1, RCA2, RCA3, and RCA3' (a subform of RCA3) have agreement with average molecular masses from electrospray mass spectrometry of 4537, 4543, 4532, and 4560 kD, respectively. The only sites for serine phosphorylation are near or at the C termini and hence adjacent to the sites of proteolytic precursor cleavage.

カイワレダイコンの生長に及ぼす磁界環境の影響

This study wvs carried out in order to investigate the effects of magnetic field on early growth of radish (Raplianus sativus L.) seedling. The water culture system (Hyponica 401) and exposing system of various kinds of magnetic field were prepared and set the mulch, made of holes of 4×7=28, fer leaf vegetable on it. And then, the radish seeds were sowed and grown in each of mulch holes. From the experimental results, we concluded that frequency of 7 Hz and magnetic field intensity of 450 A/m were best conditions.

天然型アブシジン酸によるダイコンの抽ダイ抑制効果

Three experiments were conducted on the effect of abscisic acid (S-ABA, the natural form) on bolting of Japanese radish (Raphanus sativus L.).Exp. 1. Dry or pre-imbibed seeds of Japanese radish (cv. Taibyousoubutori) were soaked in water (control), 100 or 1, 000 ppm S-ABA for 24 or 48 hr at 15 °C and sown immediately into small planter (6 x 6 x 6 cm3) filled with soil. The planters were kept at 8 °C for 10 or 20 days and then transferred to a growth chamber kept at 22 °C (day) and 18 °C (night). Treatment with 1, 000 ppm S-ABA significantly inhibited bolting of the seedlings.Exp. 2. Four lots of seeds was soaked in water, 250, 500 or 1, 000 ppm S-ABA at 15°C for 24 hr, allowed to dry completely, stored at 4 °C for 5 months and then sown in planters as above. The inhibitory effect of S-ABA on bolting of seedling persisted throughout the drying and storage periods.Exp. 3. Pre-germinated seeds of eight Japanese radish cultivars were dipped in water or 50 ppm S-ABA at 5 °C for 20 days and then sown. In another test, young seedlings of eight radish cultivars were sprayed with water or 250 ppm S-ABA during vernalization for 14 days at 8 °C. Thereafter, they were grown in the greenhouse. Seed-dipping or foliar spray applications of S-ABA inhibited bolting. The efficiency of S-ABA, however, was cultivar-dependent ; seeds and seedlings of 'Taibyousoubutori' and 'Natsuminowase No. 3' were most sensitive to S-ABA, whereas those of Wakayama and 'Kaiwaredaikon' were less sensitive. The treatment with 50 ppm S-ABA on pre-germinated seeds was more inhibitory than was the foliar application at 250 ppm.These results show that S-ABA is useful in preventing bolting of Japanese radish.

In Vitro Antifungal Activity of a Radish (Raphanus sativus L.) Seed Protein Homologous to Nonspecific Lipid Transfer Proteins

A basic 9-kD protein was purified from seeds of radish (Raphanus sativus L.). The 43 amino-terminal amino acids show extensive sequence identity with nonspecific lipid transfer proteins from other plant species. The radish seed nonspecific lipid transfer protein-like protein inhibits the growth of several fungi in vitro.

α-l-Arabinofuranosidase from Radish (Raphanus sativus L.) Seeds

An alpha-l-arabinofuranosidase has been purified 1043-fold from radish (Raphanus sativus L.) seeds. The purified enzyme was a homogeneous glycoprotein consisting of a single polypeptide with an apparent molecular weight of 64,000 and an isoelectric point value of 4.7, as evidenced by denaturing gel electrophoresis and reversed-phase or size-exclusion high-performance liquid chromatography and isoelectric focusing. The enzyme characteristically catalyzes the hydrolysis of p-nitrophenyl alpha-l-arabinofuranoside and p-nitrophenyl beta-d-xylopyranoside in a constant ratio (3:1) of the initial velocities at pH 4.5, whereas the corresponding alpha-l-arabinopyranoside and beta-d-xylofuranoside are unsusceptible. The following evidence was provided to support that a single enzyme with one catalytic site was responsible for the specificity: (a) high purity of the enzyme preparation, (b) an invariable ratio of the activities toward the two substrates throughout the purification steps, (c) a parallelism of the activities in activation with bovine serum albumin and in heat inactivation of the enzyme as well as in the inhibition with heavy metal ions and sugars such as Hg(2+), Ag(+), l-arabino-(1-->4)-lactone, and d-xylose, and (d) results of the mixed substrate kinetic analysis using the two substrates. The enzyme was shown to split off alpha-l-arabinofuranosyl residues in sugar beet arabinan, soybean arabinan-4-galactan, and radish seed and leaf arabinogalactan proteins. Arabinose and xylose were released by the action of the enzyme on oat-spelt xylan. Synergistic action of alpha-l-arabinofuranosidase and beta-d-galactosidase on radish seed arabinogalactan protein resulted in the extensive degradation of the carbohydrate moiety.

Analysis of two novel classes of plant antifungal proteins from radish (Raphanus sativus L.) seeds.

Two novel classes of antifungal proteins were isolated from radish seeds. The first class consists of two homologous proteins (Rs-AFP1 and Rs-AFP2) that were purified to homogeneity. They are highly basic oligomeric proteins composed of small (5-kDa) polypeptides that are rich in cysteine. Both Rs-AFPs have a broad antifungal spectrum and are among the most potent antifungal proteins hitherto characterized. In comparison with many other plant antifungal proteins, the activity of the Rs-AFPs is less sensitive to the presence of cations. Moreover, their antibiotic activity shows a high degree of specificity to filamentous fungi. The amino-terminal regions of the Rs-AFPs show homology with the derived amino acid sequences of two pea genes specifically induced upon fungal attack, to gamma-thionins and to sorghum alpha-amylase inhibitors. The radish 2S storage albumins were identified as the second novel class of antifungal proteins. All isoforms inhibit growth of different plant pathogenic fungi and some bacteria. However, their antimicrobial activities are strongly antagonized by cations.

Sequences of the Cotton Group 2 LEA/RAB/Dehydrin Proteins Encoded by Lea3 cDNAs

The 18 cloned cotton Lea (late embryogenesis-abundant) mRNAs are a diverse group encoding proteins that may be desiccation protectants (5). Lea mRNAs are coordinately induced by ovule abscission in cotton embryos during the postabscission stage before desiccation (5) and in cultured embryos by desiccation, osmotic stress, or exposure to ABA, a plant hormone that may be a transducer of water-related stresses (6). Homologs of the cotton Lea3 cDNA clone D 1I (1) have been identified as rab (responsive to ABA) in rice seedlings exposed to ABA or salt (10) and maize embryos and calli exposed to ABA (9), Dhn (dehydrin) in maize and barley seedlings exposed to water stress (2), pcD27-04 and pcC6-19 in dried leaves and ABA-treated calli of the resurrection plant Craterostigma plantagineum (7), RSLEA2 in dry seeds of radish (8), and TAS14 in tomato seedlings exposed to osmotica or ABA (4). Although the organization and amino acid sequences of these Group 2 LEA/RAB/dehydrin proteins are highly conserved, the carboxy terminus of the cotton D 1I LEA3 protein is singularly divergent. Because the nucleotide sequence of D 11 could encode a more typical terminus if there were frame-shift mutations or sequencing errors (2), we have independently determined the sequence of Dl I and, for comparative purposes, also determined the entire nucleic acid sequence of D147b and part of D71 and D131, three additional Lea3 cDNA clones (Table I). The nucleotide and deduced amino acid sequences of D147b and a comparison with those of Dl I are presented in Figure 1. We note that the published sequence of DIl (1) contains two relatively unimportant errors. First, D 1I contains two additional nucleotides at the 5' end that were not previously reported. Second, D 1 contains a G at D 11 nucleotide 353, not a C as previously reported. The latter cor' Supported by National Institutes of Health grant No. GM29495 to G.A.G. and U.S. Department of Agriculture/Cooperative State Research Service grant No. 91-37100-6615 to T.J.C.

Plasma Membrane Ca-ATPase of Radish Seedlings

The effect of calmodulin on the activity of the plasma membrane Ca-ATPase was investigated on plasma membranes purified from radish (Raphanus sativus L.) seedlings. Calmodulin stimulated the hydrolytic activity and the transport activity of the plasma membrane Ca-ATPase to comparable extents in a manner dependent on the free Ca(2+) concentration. Stimulation was marked at low, nonsaturating Ca(2+) concentrations and decreased increasing Ca(2+), so that the effect of calmodulin resulted in an increase of the apparent affinity of the enzyme for free Ca(2+). The pattern of calmodulin stimulation of the plasma membrane Ca-ATPase activity was substantially the same at pH 6.9 and 7.5, in the presence of ATP or ITP, and when calmodulin from radish seeds was used rather than that from bovine brain. At pH 6.9 in the presence of 5 micromolar free Ca(2+), stimulation of the plasma membrane Ca-ATPase was saturated by 30 to 50 micrograms per milliliter bovine brain calmodulin. The calmodulin antagonist calmidazolium inhibited both basal and calmodulin-stimulated plasma membrane Ca-ATPase activity to comparable extents.

Promotive Effects of DCPTA on Seedling Development and Growth of Radish

A radish (Raphanus sativus L. cv. Scarlet turnip white tipped) seedling growth test was developed to examine promotive effects of 2-(3,4-dichlorophenoxy) triethylamine (DCPTA) on seedling vigor and plant development. Compared with controls, seed treatment using 30 μm DCPTA significantly (P = 0.05) enhanced the rates of root and hypocotyl elongation and seedling dry weight. Enhanced hypocotyl development by DCPTA showed a significant linear correlation (r = 0.83) with the increased taproot yield of mature plants grown from DCPTA-treated seeds. The harvestable taproot yield and harvest index of plants grown from seeds treated with 30 μm DCPTA were increased 109% and 38%, respectively, as compared with controls. Incubation of radish seeds in 30 μm DCPTA with actinomycin-D, alpha-amanitin, amisomycin, or cordycepin significantly reduced DCTPA-mediated seedling growth. These results indicate that nuclear gene expression and translation of mRNA on 80S ribosomes are required for the acceleration of seedling development by DCPTA.

Coat-imposed dormancy by coumarin in radish seeds: the influence of light

Abstract Continuous white light induced a secondary dormancy in 40% of radish seeds (Raphanus sativus L. «Saxa»); this value was increased to 80% by coumarin 2 × 10 4 M. Either darkness or removal of the coat were found to be dormancy breaking agents for seeds not germinated in the above conditions.

Effects of selected trace metals on germinating seeds of six plant species

Seeds of cabbage, lettuce, millet, radish, turnip, and wheat were treated with solutions containing Be, Ni, Tl, or V, and subsequent effects on seed germination and radicle elongation were measured after three days. Treatment with low concentrations of Be, Ni, or V stimulated root elongation in most species. Higher concentrations of these elements and all treatment with Tl caused reductions in root elongation. In general, turnip and lettuce were the most sensitive of the plants studied to the metals tested, while wheat and millet were the least sensitive.

Occurrence of the Beet Leafhopper-Transmitted Virescence Agent in Red and Daikon Radish Seed Plants in Washington State

Occurrence of the Beet Leafhopper-Transmitted Virescence Agent in Red and Daikon Radish Seed Plants in Washington State

Response to osmotic medium and fusicoccin by seeds of radish (Raphanus sativus) in the early phase of germination

The effect of increasing osmotic values of the medium (mannitol) on the growth and the response mechanisms of seeds of radish (Raphanus sativus L., cv. Ton do Rosso Quarantino) during the early phase of germination was investigated in the presence or absence of fusicoccin (FC). Decreasing the water potential in the medium inhibited the growth and the evolution of protein synthesis and enhanced H+ extrusion, net uptake of K+ and malic acid synthesis. FC, which stimulates these latter functions, counteracted the inhibitory effect of the decreasing water potential of the medium on growth and protein synthesis. Neither in the absence nor in the presence of FC did decreasing water potential of the medium enhance the synthesis of soluble sugars and amino acids to support the osmotic pressure of the seeds. The osmotic and water potentials of the seeds increased during germination. FC made the increase more rapid, while mannitol kept both potentials low. The pressure potentials of the seeds also decreased with time, and both FC and mannitol enhanced this change. If the seeds were without turgor, the development of protein synthesis was blocked. The seeds counteract the effect of decreasing water potentials in the medium by: a) enhancing H+ extrusion (and, as a consequence, wall loosening and transport mechanisms) and the synthesis of malic acid as apparent in the presence of FC; b) regulating the osmotic potentials of the cells (with a lower dilution of the osmotic compounds present in the seeds due to the diminished uptake of water); c) controlling the growth through the effects of a) and b) on the pressure potentials (internal hydrostatic pressure) of the seeds and on protein synthesis.