Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| a comparative analysis of phloem exudate proteins from cucumis melo, cucumis sativus and cucurbita maxima by polyacrylamide gel electrophoresis and isoelectric focusing. | proteins in sieve tube exudate from cucumis melo l., cucumis sativus l. and cucurbita maxima duch. were analysed by gel electrophoresis and isoelectric focusing. estimated molecular weights and isoelectric points for the major and minor proteins from each plant species are presented. electrophoresis revealed striking differences between the protein complements of exudatc from the two genera investigated. similarly, although a few exudate proteins from the two species of cucumis possessed identic ... | 1976 | 24424601 |
| some changes in the composition of the fruit of the glasshouse cucumber (cucumis sativus) during growth, maturation and senescence. | 1976 | 5628 | |
| fungicide residues. part v. determination of residues of chloraniformethan in grain and cucumbers by gas chromatography. | 1976 | 1259174 | |
| isolation and characterization of indole-3-acetaldehyde reductases from cucumis sativus. | in a continuing study of the biosynthetic pathway and regulatory mechanisms governing indole-3-acetic acid (auxin) formation, we report the isolation and initial characterization of three distinct indole-3-acetaldehyde reductases from cucumber seedlings. these enzymes catalyze the reduction of indole-3-acetaldehyde to indole-3-ethanol with the concomitant oxidation of nad(p)h to nad(p)+. two of the reductases are specific for nadph as second substrate, while the third is specific for nadh. the e ... | 1976 | 2607 |
| the enzymic formation of long chain aldehydes and alcohols by alpha-oxidation of fatty acids in extracts of cucumber fruit (cucumis sativus). | 1. an enzyme system that catalyses the alpha-oxidation of fatty acids to shorter chain products is present in acetone powders of cucumber fruits. 2. in the absence of nad+, the predominant product from palmitic acid is pentadecanal. addition of nad+ gives rise to a homologous series of n-alkanals, the concentrations of which are in the same order as that reported in the volatile products formed on homogenization of cucumbers, i.e. c15 greater than c14 greater than c13 greater than c12. 3. pentad ... | 1976 | 1252478 |
| developmental studies of nad-malate dehydrogenase isozymes in the cotyledon of cucumber seedlings grown in darkness and in light. | the total activity of nad-malate dehydrogenase (e.c. 1.1.1.37; mdh) in the cotyledons of cucumber (cucumis sativus l.) seeds and seedlings increased 10fold during the first 3 days of germination in darkness and then declined gradually to one third of the peak activity after 10 days. exposure of the seedlings to light at day 3 sharply reduced the activity to one third of the peak activity within 1 day but the residual activity remained fairly constant from day 4 to day 10. in extracts of cotyledo ... | 1976 | 24424831 |
| collaborative study of the determination of endosulfan, endosulfan sulfate, tetrasul, and tetradifon residues in fresh fruits and vegetables. | a method for the determination of endosulfan i, endosulfan ii, endosulfan sulfate, tetrasul, and tetradifon residues in fresh fruits and vegetables was studied collaboratively. the method consists of extraction of the product with acetonitrile, ether and elution from a florisil column with mixtures of hexane, methylene chloride, and acetonitrile, and determination of the residues by electron capture gas-liquid chromatography. this method was studied by 8 collaborators, using apples and cucumbers ... | 1976 | 1249036 |
| similarities among ribosomal rna's of angiospermae and gymnospermae. | competitive hybridization of ribosomal rnas was used to estimate similarities of nucleotide sequences between species of angiospermae and gymnospermae. similarities have been measured with respect to cucumis sativus. in angiospermae the nucleotide sequences are highly conserved except in the species of the family of compositae, where the percentages of similarity are clearly lower. in the gymnospermae the lowest similarity has been observed with torreya californica. a relationship is hypothesize ... | 1976 | 1011263 |
| deep-sea macroplanktonic sea cucumbers: suspended sediment feeders captured from deep submergence vehicle. | observations in situ confirm the swimming and feeding behavior in previously unreported dense assemblages of the holothurian peniagone diaphana, at a depth of 2000 meters, off southern california. proximate analysis of captured specimens indicates that this organism may represent a numerically significant, but low organic content member of many near-bottom deep-sea communities. | 1976 | 17840307 |
| microbody malate dehydrogenase isozyme in cotyledons of cucumis sativus l. during development. | the properties of the microbody malate dehydrogenase (ec 1.1.1.37) (mdh) isozyme from cotyledons of cucumus sativus l. were compared during development. it is concluded that the isozyme remains unaltered, despite the transition from glyoxysomal to peroxisomal function that occurs during greening of the cotyledons. this conclusion is based on electrophoretic behavior, chromatographic elution from deae-cellulose, molecular weight, kinetic behavior, and immunological identity. in most cases, the di ... | 1976 | 16659695 |
| organochlorine insectide residues in vegetables of the kitakyushu district, japan--1971-74. | the residue levels of organochlorine insecticides bhc, ddt, endrin, and dieldrin in the kitakyushu district, japan, were monitored from 1971 to 1974. agricultural uses of these insecticides were banned in 1970. bhc isomers, alpha, beta, gamma, and delta-bhc were detected in all vegetable samples taken; beta-bhc residue appeared in the highest levels. the proportions of each bhc isomer in total bhc residues were much different from those in the technical product. average residue levels of alpha, ... | 1976 | 1005058 |
| the formation of cis-3-nonenal, trans-2-nonenal and hexanal from linoleic acid hydroperoxide isomers by a hydroperoxide cleavage enzyme system in cucumber (cucumis sativus) fruits. | 1. a particulate enzyme fraction and an acetone powder preparation from cucumber fruits cleaved 9- and 13-hydroperoxyoctadecadienoic acids to form volatile aldehydes and oxoacid fragments. 2. from the 9-hydroperoxide, the major volatile fragments were cis-3-nonenal and trans-2-nonenal using particulate enzyme and acetone powder preparations, respectively. 3. hexanal was the only significant volatile fragment from the 13-hydroperoxide. 4. the particulate enzyme system was equally effective on bot ... | 1976 | 8126 |
| cobalt and plant development: interactions with ethylene in hypocotyl growth. | co(2+) promoted elongation of hypocotyl segments of light-grown cucumber (cucumis sativus) seedlings. time course and dose response data are presented and interactions with iaa, gibberellin, cyclohexanol, and cotyledons described. segments without cotyledons responded to co(2+) only if grown in gas-tight vessels with iaa added. when bases of cotyledons were ringed with an inhibitor of auxin transport, co(2+) caused no growth promotion in the hypocotyl. co(2+) prevented lateral swelling of hypoco ... | 1976 | 16659591 |
| auxin biogenesis: subcellular compartmentation of indoleacetaldehyde reductases in cucumber seedlings. | subcellular fractionation of cucumber (cucumis sativus l.) seedlings was achieved, and two of the enzymes in the auxin biosynthetic pathway were localized. nadh-specific indoleacetaldehyde reductase activity was observed only in the cytosol fractions obtained from separated hypocotyl and cotyledon tissue. in contrast, a portion of the nadph-specific indoleacetaldehyde reductase activity was associated with a microsomal fraction derived from these tissues. the nadph-specific indoleacetaldehyde re ... | 1976 | 16659584 |
| the enzymic cleavage of linoleic acid to c9 carbonyl fragments in extracts of cucumber (cucumis sativus) fruit and the possible role of lipoxygenase. | 1. homogenates and acetone powders of cucumber fruits catalyse the enzymic conversion of linoleic acid to aldehyde and oxoacid fragments in high yield, up to 60% with acetone powder extracts. 2. the major products are trans2-nonenal--a major component of the characteristic odour of cucumber--and 9-oxononanoic acid. 3. the cleavage reaction is a heat-labile, aerobic process, optimal at ph 6 (approx.). 4. substrate specificity studies indicate that a lipoxygenase-type of reaction is involved in th ... | 1976 | 820376 |
| chloroplast biogenesis: xx. accumulation of porphyrin and phorbin pigments in cucumber cotyledons during photoperiodic greening. | a study of greening in cucumber (cucumis sativus l.) cotyledons grown under a light (14-hour) dark (10-hour) photoperiodic regime was undertaken. the pools of protoporphyrin ix, mg-protoporphyrin ix monoester, protochlorophyllide, and protochlorophyllide ester were determined spectrofluorometrically. chlorophyll a and b were monitored spectrophotometrically. pigments were extracted during the 3rd hour of each light period and at the end of each subsequent dark period during the first seven growt ... | 1977 | 16660176 |
| [interaction of ascorbate oxidase with inorganic anions]. | from the peelings of cucumber cucumis sativus and marrow squash cucurbita pepo var. giramontia highly purified ascorbate oxidase preparations were obtained. molecular weights, optical and epr spectra, total copper contents and different type copper contents of the both proteins were similar. the effects of nan3, kcn, i- and f- on the optical and epr spectra of the proteins were studied. the incubation of ascorbate oxidase with these anions lead to the partial reduction of the copper. the data ob ... | 1977 | 588636 |
| extraction and gas-liquid chromatographic determination of hexachlorophene from several plant tissues. | conditions are described for extraction, cleanup, derivatization, detection, and quantitation of hexachlorophene (hcp) residues from several types of plant material. wet plant tissue was homogenized and extracted with ethyl ether, dried, and methylated with excess diazomethane. samples were precleaned by column chromatography on silica gel with benzene-petroleum ether (1 + 1), and then 1-10 microliter concentrated sample was chromatographed on a 6' column of 3% se-30 on 80-100 mesh gas-chrom q. ... | 1977 | 893328 |
| subcellular localization and developmental changes of aspartate-alpha-ketoglutarate transaminase isozymes in the cotyledons of cucumber seedlings. | the total activity of aspartate-alpha-ketoglutarate transaminase in the cotyledons of cucumber (cucumis sativus l.) seeds increased 17-fold during the first 2 days of germination in darkness and then declined gradually to 20% of the peak activity after 10 days. exposure of the seedlings to light at day 3 accelerated the decline. the enzyme in the cotyledon extracts from seedlings at various ages was resolved into six distinct isozymes by starch gel electrophoresis. isozymes 1 and 2 were glyoxyso ... | 1977 | 16659941 |
| [determination of patulin in foodstuffs part ii: determination of patulin in tomatoes, pears, apples cucumbers and plums (author's transl)]. | an analytical method for the determination of patulin in tomatoes, pears, apples, cucumbers and plums is described. the determination limit of the method is 40 mug patulin/kg. with additions between 100-500 mug patulin/kg the recovery rates lie between 86--95%. after a pre-purification of the crude extract by column chromatography and liquid-liquid extraction the patulin is determined thin-layer chromatographically by reflectance measurement at 273 nm. | 1977 | 855502 |
| the role of cotyledons in phototropism of de-etiolated seedlings. | simulated "phototropic" curvatures caused by differential masking of the cotyledons of de-etiolated seedlings exposed to white light are unconnected with true phototropism. in cucumis sativus l. and helianthus annuus l. such curvatures result from a red-light-induced inhibition coming from the exposed cotyledon. true phototropic bending in these species under long-term exposure to fairly high irradiances (as in nature) is a response to blue light. it occurs even when cotyledons are completely co ... | 1977 | 24419892 |
| phenylalanine ammonia lyase and cinnamic acid hydroxylases as assembled consecutive enzymes on microsomal membranes of cucumber cotyledons: cooperation and subcellular distribution. | 1. cooperation between phenylalanine ammonia-lyase (pal, ec 4.3.1.5) and cinnamic acid hydroxylases was investigated using microsomal fractions from cotyledons of cucumber (cucumis sativus l.). the interpretations were based on experiments which demonstrate a limited exchange between the pool of cinnamic acid formed by the membrane-bound phenylalanine ammonia-lyase and the cinnamic acid pool external to the enzyme-membrane system. 2. the extent of cooperation between the microsomal enzymes was p ... | 1977 | 24419691 |
| sterols of male and female flowers of cucumis sativus. | sterols of male and female flowers of cucumis sativus l. were similar in composition. the principal compound was 24ξ-ethyl-5α-cholesta-7,22-dien-3β-ol. five other 5α-δ(7) were detected: 24ξ-methyl-7-ene, 24ξ-ethyl-7-ene, 24-ethyl-7,24(28)z-diene, 24ξ-ethyl-7,25-diene and 24ξ-ethyl-7,22,25-triene. small amounts of δ(5) (cholesterol, 24ξ-methylcholesterol and 24ξ-ethylcholesterol) were detected. the possible significance of these sterols is discussed. | 1977 | 24419688 |
| [thin-layer chromatographic determination of chlordimeform in cucumbers and apples]. | the author describes two methods for the thin-layer chromatographic determination of chlordimeform residues in cucumbers and apples. chlordimeform is determined alone or together with its relevant metabolites after conversion into 4-chloro-o-toluidine. the limit of detection is 0.1 and 0.05 p.p.m., respectively. the rate of recovery is 76-85 and 90-105%, respectively. studies on the stability of the residues and on the metabolism and distribution of chlordimeform in cucumbers are discussed. | 1977 | 876348 |
| influence of nitrogen supply on host and multiplication of cucumber mosaic virus. | the effect of several concentrations of nitrogen (0, 21, 70, 210, 420 and 630 ppm) on the growth and multiplication of cucumber mosaic virus in cucumber (cucumis sativus l. barshati) grown in sand culture was studied. the effect of nitrogen nutrition on the concentration of virus appeared to be directly related to vegetative growth of the host. 420 ppm level yielding the best growth also showed the highest virus concentration and total nitrogen percentage at 30th day of infection. | 1977 | 67769 |
| occurrence of patulin in fruit and vegetables. | in different varieties of apples and pears suffering from brown rot, patulin was found in about 50 p. 100 of samples investigated (about 120). patulin levels as high as 1 g/kg rotten material were found 2-3 days after the fruit was removed from the cold store where it had been stored for 5 months. a significant diffusion into the healthy plant tissue was not observed in apples, but in peaches, tomatoes and pears. vegetable products with natural patulin content: apples, pears, peaches, apricots, ... | 1977 | 613910 |
| [patulin in foods of vegetable origin. 2. several kinds of fruit and vegetables and fruit and vegetable products (author's transl)]. | patulin was found in fruit with spontaneous brown rot (bananas, pineapples, grapes, peaches, apricots) as well as in moldy compots and in sallow-thorn juice. fruit, vegetables and fruit and vegetable product were artificially infected with penicillium expansum, p. urticae and byssochlamys nivea; patulin was subsequently found in peaches, apricots, greengages, bananas, strawberries, honeydew melons, tomatoes, red and green paprika, cucumbers and carrots; in several kinds of compot, in tomato juic ... | 1977 | 857490 |
| [mode of action and inhibition of polygalacturonase covalently bound to polysaccharide and glass carriers]. | endo-polygalacturonase (ec 3.2.1.15.) from aspergillus spec. is much changed as far as its mode of action and the interaction with vegetable inhibitors of pectinase (from green beans and cucumbers) are concerned when it is covalently bound to insoluble carriers (sepharose, cellulose powder, macroporous glass and nonporous ballotinis). whereas a 2% degradation of substrate by the soluble enzyme caused a 50% decrease of viscosity of citrus pectic acid, the comparable degradation of substrate was i ... | 1978 | 692641 |
| plant microbody proteins. purification and glycoprotein nature of glyoxysomal isocitrate lyase from cucumber cotyledons. | 1. isocitrate lyase from cotyledons of cucumber seedlings (cucumis sativus) has been purified 100-fold. two methods of preparing the soluble glyoxylate cycle enzyme are described: an elaborated method which used crude extracts of cucumber cotyledons, and another procedure which started with purified glyoxysomes from 4-day-old cotyledons and included a separation of glyoxysomal matrix enzymes by zonal centrifugation. the product behaved as a single species when tested by (a) polyacrylamide gel el ... | 1978 | 103713 |
| regulation of glyoxysomal enzymes during germination of cucumber: 2. isolation and immunological detection of isocitrate lyase and catalase. | the glyoxysomal enzymes isocitrate lyase and catalase have been isolated from etiolated cucumber (cucumis sativus) cotyledons. the enzymes co-purified through polyethyleneimine precipitation and (nh(4))(2)so(4) precipitation, and were resolved by gel filtration on sepharose 6b followed by chromatography on diethylaminoethyl-cellulose (isocitrate lyase) or hydroxylapatite (catalase). purity of the isolated enzymes was assessed by sodium dodecyl sulfate-polyacrylamide electrophoresis, isoelectric ... | 1978 | 16660600 |
| distinction between nuclear satellite dnas and chloroplast dna in higher plants. | triton x-100 solubilized chloroplast dna but not nuclear dna from a mixture of chloroplasts and nuclei. the buoyant density of chloroplast dna was different from that of the satellite dna in all of the species examined (phaseolus coccineus, cucumis sativus, cucumis melo, antirrhinum majus, vicia faba, oenothera fruiticosa youngii). chloroplast dna constituted between 4.3% and 0.25% of the total leaf dna in these species, and was present as 5 to 20 copies in each chloroplast. | 1978 | 16660649 |
| albumins, glyoxysomal enzymes and globulins in dry seeds of cucumis sativus: qualitative and quantitative analysis. | 1) albumins and globulins were prepared from dry seeds of cucumbers (cucumis sativus) by differential extraction. the globulin fraction was analyzed by gel electrophoresis under denaturing conditions in the presence and absence of mercaptoethanol. the subunit (mr = 54000) of the tetramer (mr = 240000) was shown to be composed of two different peptides. microheterogeneity rendered the exact interpretation of the analysis difficult. 2) glyoxysomal proteins were already present in dry seeds: malate ... | 1978 | 422126 |
| lipases in the storage tissues of peanut and other oil seeds during germination. | the castor-bean endosperm-the best-studied material of reserve lipid hydrolysis in seed germination-was previously shown to have an acid lipase and an alkaline lipase having reciprocal patterns of development during germination. we studied oil seeds from 7 species, namely castor bean (ricinus communis l.), peanut (arachis hypogaea l.), sunflower (helianthus annus l.), cucumber (cucumis sativus l.), cotton (gossypisum hirsutum l.), corn (zea mays. l.) and tomato (lycopersicon esculentum mill.). t ... | 1978 | 24414640 |
| light-dependent emission of hydrogen sulfide from plants. | with the aid of a sulfur-specific flame photometric detector, an emission of volatile sulfur was detected from leaves of cucumber (cucumis sativus l.), squash and pumpkin (cucurbita pepo l.), cantaloupe (cucumis melo l.), corn (zea mays l.), soybean (glycine max [l.] merr.) and cotton (gossypium hirsutum l.). the emission was studied in detail in squash and pumpkin. it occurred following treatment of the roots of plants with sulfate and was markedly higher from either detached leaves treated via ... | 1978 | 16660257 |
| effects of brine treatment on pesticide residues during recycling of pickling brine. | the effects of 2 pickle brine recycling treatments on residues of selected insecticides, herbicides, and fungicides are presented. residues were determined in raw and brined cucumbers, in untreated brine, and in brine following pasteurization or chemical (naoh) treatment. the samples were extracted with acetone, partitioned into methylene chloride, cleaned up by gel permeation chromatography, and quantitatted by gas-liquid chromatography using nitrogen/phosphorus, electron capture, and flame pho ... | 1978 | 730651 |
| regulation of glyoxysomal enzymes during germination of cucumber: i. developmental changes in cotyledonary protein, rna, and enzyme activities during germination. | developmental patterns of glyoxylate cycle and photosynthetic activities have been correlated with electrophoretic profiles of cotyledonary rna and protein in both light- and dark-grown cucumber seedlings (cucumis sativus l.) cytoplasmic rrna increases 10-fold between days 0 and 5, and the steepest increase coincides with the most rapid rise in activities of the glyoxysomal enzymes, isocitrate lyase and malate synthase. chloroplast rrna and ribulose bisphosphate (rubp) carboxylase begin rising a ... | 1978 | 16660555 |
| analysis of plant genomes. iv. isolation and characterization of satellite dna components from two dicotyledons cucumber (cucumis sativus) and radish (raphanus sativus). | satellite dna fractions from cucumber and radish, two plants having low dna contents and relatively small chromosomes, were isolated and characterized. reassociation studies of satellite and total nuclear dna showed that the satellite fractions in these two plants contain most of the rapidly reassociating dna. cucumber satellite i was found to contain one major component (70% of the total satellite) having a density of 1.706 g/cm3 and a tm of 90.5 degrees c and a minor component with a density o ... | 1978 | 688067 |
| chloroplast biogenesis: xxii. contribution of short wavelength and long wavelength protochlorophyll species to the greening of higher plants. | the contribution of short and long wavelength membrane-bound fluorescing protochlorophyll species to the over-all process of chlorophyll formation was assessed during photoperiodic growth. protochlorophyll forms were monitored spectrofluorometrically at 77 k during the first six light and dark cycles in homogenates of cucumber (cucumis sativus l.) cotyledons grown under a 14-hour light/10-hour dark photoperiodic regime, and in cotyledons developing in complete darkness. in the etiolated tissue, ... | 1978 | 16660394 |
| mechanisms of resistance to sulfur dioxide in the cucurbitaceae. | the relative resistance of four cultivars of the cucurbitaceae (cucumis sativus l. cv. national pickling, and inbred line sc 25; cucurbita pepo l. cv. prolific straightneck squash, and cv. small sugar pumpkin) to so(2) was determined. according to plots of the degree of exposure to so(2) (which depends on the so(2) concentration and the duration of the exposure), there is an 8-fold difference in resistance to this toxic gas among these cultivars. however, if the degree of injury is plotted as a ... | 1978 | 16660380 |
| absence of parallelism between polyamine and nucleic acid contents during induced growth of cucumber cotyledons. | the cytokinins (benzyladenine or benzyladenosine) decreased spermidine and spermine contents despite increasing putrescine content, when administered to isolated cotyledons of cucumis sativus l. var. guntur in organ culture. kcl decreased putrescine contents, although marginally increasing polyamine contents. the cytokinins and/or kcl augmented nucleic acid biosynthesis and accumulation, resulting in enhanced growth and differentiation of the isolated cotyledons. these observations show that pol ... | 1978 | 656071 |
| photosynthetic apparatus in chilling-sensitive plants : ii. changes in free fatty acid composition and photoperoxidation in chloroplasts following cold storage and illumination of leaves in relation to hill reaction activity. | the composition of free fatty acids (ffa) in relation to hill reaction activity and photoperoxidation of lipids was studied in chloroplasts isolated from fresh, cold and dark-stored as well as illuminated leaves of lycopersicon esculentum mill., phaseolus vulgaris l. and cucumis sativus l. following the cold and dark-storage of leaves the loss of hill reaction activity is accompanied by approximately a 5-fold increase in the amount of ffa and by an increase in the percentage of unsaturated ffa, ... | 1978 | 24414468 |
| photosynthetic apparatus in chilling-sensitive plants : i. reactivation of hill reaction activity inhibited on the cold and dark storage of detached leaves and intact plants. | chloroplast isolated from the detached leaves of chilling-sensitive plants-phaseolus vulgaris l., cucumis sativus l., and lycopersicon esculentum mill.-stored in the cold for 2-4 days in the dark exhibit an almost complete loss of hill reaction activity, which on illumination of leaves is restored to almost the original level. in contrast, illumination of either chloroplast suspensions or homogenates from leaves stored in the cold in the dark does not cause restoration of electron transport. col ... | 1978 | 24414467 |
| concanavalin a-mediated agglutination of plant plastids. | cucumber (cucumis sativus l.) and pear (pyrus domestica medik.) fruit proplastids, and pea (pisum sativum l., cv. meteor) leaf chloroplasts, extracted by osmotic rupture of protoplasts isolated after degradation of the cell walls by cellulase and pectinase, agglutinated in the presence of con a. agglutination of cucumber proplastids was inhibited by anti-con a and by methyl α d-gluco/manno pyranosides but not by methyl α d-galactopyranoside. fluorescein isothiocyanate-conjugated con a (fitc-con ... | 1978 | 24413938 |
| cucumber seedling indoleacetaldehyde oxidase. | extracts of light-grown cucumis sativus l. seedlings catalyzed the oxidation of indole-3-acetaldehyde to indole-3-acetic acid. no added cofactors were required. inhibitor studies indicated that the enzyme is a metalloflavoprotein. while indole-3-aldehyde, benzaldehyde, and phenylacetaldehyde partially inhibited the oxidation of indole-3-acetaldehyde, suggesting that they may serve as alternative substrates, it is proposed that indoleacetaldehyde is the major substrate in vivo. 2,4-dichlorophenox ... | 1978 | 16660220 |
| indoleacetaldehyde in cucumber seedlings. | the presence of indoleacetaldehyde in cucumber (cucumis sativus l.) cotyledons was demonstrated by thin layer chromatographic r(f) values in three solvent systems, by the formation and hydrolysis of a bisulfite adduct, and by chemical reduction to indoleethanol and oxidation to indoleacetic acid. bioassays indicated a minimum indoleacetaldehyde content in etiolated cotyledons of 0.7 mug per kg fresh weight. tissue samples from all parts of both green and etiolated cucumber seedlings reduced exog ... | 1978 | 16660219 |
| plant plasma membrane. correlation between glucan synthase ii activity and a mannosyl transferase activity. | in cotyledons of germinating cucumber seeds (cucumis sativus), plasma membranes were investigated biochemically and partially characterized. glucan synthease ii was utilized as a marker to locate plasma membrane vesicles within fractions obtained by differential centrifugation or within sucrose gradients used either in zonal centrifugations or in sedimentations to equilibrium density. thorough homogenization led to a homogeneous population of plasma membrane vesicles which could be clearly separ ... | 1979 | 116951 |
| the control of food mobilisation in seeds of cucumis sativus l. : ii. the role of the embryonic axis. | removal of the embryonic axis from germinated cucumber seeds, either on the second of fourth day after imbibition, subsequently results in reduced rates of lipid and protein degradation and in the accumulation of free sugars and amino acids in the cotyledons. these isolated cotyledons show an inherent capacity for expansion growth which apparently results from an increased rate of water uptake. when water uptake is inhibited by incubating samples in polyethylene glycol the rate of lipid degradat ... | 1979 | 24318331 |
| the control of food mobilisation in seeds of cucumis sativus l. : i. the influence of embryonic axis and testa on protein and lipid degradation. | the development of maximal rates of lipid and protein hydrolysis in cucumber cotyledons depends upon the removal of the testa and the presence of the embryonic axis. the testa appears to exert at least part of its inhibitory influence by suppressing the development of enzyme activity associated with lipolysis and proteolysis. there is, however, no evidence to suggest that the presence of the embryonic axis is a pre-requisite for the development of optimal enzyme activity. | 1979 | 24318330 |
| identification of traumatin, a wound hormone, as 12-oxo-trans-10-dodecenoic acid. | 12-oxo-trans-10-dodecenoic acid (trans-10-oda) is an oxidation product of polyunsaturated fatty acids in plant tissues. the structural similarity of trans-10-oda and traumatic acid, a compound considered to be a wound hormone, suggested that trans-10-oda might be a precursor of traumatic acid. both trans-10-oda and traumatic acid were active in the wehnelt bean assay. the results were more consistent with trans-10-oda than with traumatic acid. cucumber (cucumis sativus l. var. national pickling) ... | 1979 | 16660762 |
| light-dependent induction of polyunsaturated fatty acid biosynthesis in greening cucumber cotyledons. | greening cucumber (cucumis sativus l.) cotyledons exhibited dramatic increases in the ability to desaturate exogenously added [1-(14)c]oleic acid and [1-(14)c]linoleic acid within 2 to 3 hours of illumination. these increases were effectively inhibited by 10 micrograms per milliliter cycloheximide. oleate desaturation remained at a high level in constant light for 5 to 6 days after induction and then declined by about 50%; when returned to the dark, the tissue showed a sharp decrease in conversi ... | 1979 | 16660723 |
| chloroplast biogenesis: xxiv. intrachloroplastic localization of the biosynthesis and accumulation of protoporphyrin ix, magnesium-protoporphyrin monoester, and longer wavelength metalloporphyrins during greening. | the intraplastidic localization of the endogenous metabolic pools from protoporphyrin to protochlorophyll was determined in cucumis sativus. the endogenous protoporphyrin, mg-protoporphyrin monoester + longer wavelength metalloporphyrins, protochlorophyllide and protochlorophyllide ester were membrane-bound. protoporphyrin was synthesized in the stroma and subsequently became associated with the membranes. the membrane-associated protoporphyrin was then converted into mg-protoporphyrin monoester ... | 1979 | 16660702 |
| cytoplasmic streaming in the root cortex and its role in the delivery of potassium to the shoot. | the influence of cytochalasin b (cb), a potent inhibitor of cytoplasmic streaming, on (86)rb-labelled k(+) translocation by detopped lycopersicon esculentum mill., cucumis sativus l. and zea mays l. plants was examined by measuring the radioactivity in xylem exudate before and after the addition of cb to the medium bathing the roots. cb caused complete cessation of cytoplasmic streaming in root segments within 15 min but was without effect on either total (86)rb uptake or exudation. thus factors ... | 1979 | 24317771 |
| a lectin from the exudate of the fruit of the vegetable marrow (cucurbita pepo) that has a specificity for beta-1,4-linked n-acetylglucosamine oligosaccharides. | lectins are present in the exudate (presumably from the phloem) of the fruits of three species of the cucurbitaceae, namely vegetable marrow (cucurbita pepo), melon (cucumis melo) and cucumber (cucumis sativus). they are all strongly inhibited in their activities by chitin oligosaccharides, but only weakly by n-acetylglucosamine. glycopeptides from soya-bean agglutinin and fetuin are also strong inhibitors of cucurbita pepo lectin, indicating that it interacts with internal n-acetylglucosamine r ... | 1979 | 534476 |
| effects of plant diversity and time of colonization on an herbivore-plant interaction. | experimental field plantings showed that plant diversity strongly affected the population dynamics of a specialist herbivore, the striped cucumber beetle, acalymma vittata (fab.) (coleoptera: chrysomelidae). population densities over time were characterized by two peaks in numbers (from colonization and reproduction, respectively) and were consistently higher in cucumber monocultures (cucumis sativus l.) than in polycultures of cucumbers, corn (zea mays l.), and broccoli (brassica oleracea l.). ... | 1979 | 28310287 |
| fluorescent pseudomonads in the rhizosphere of plants and their relation to root exudates. | fluorescent pseudomonads were present in chernozem soil not influenced by plant roots (10(3)-10(4) per g dry soil) in the rhizosphere soil of various plants (10(4)-10(5) per g soil) and on roots (10(3) to 10(7) per g fresh roots), depending on the species and age of the plant. relative species representation of fluorescent pseudomonads changed on the roots and in the plant rhizosphere as compared with free soil. pseudomonas fluorescens, representing 60-93% of the population of fluorescent pseudo ... | 1980 | 6769769 |
| physiological effects of cotyledons on gibberellin-induced cucumber hypocotyl elongation. | the cotyledon requirement for gibberellin-induced hypocotyl elongation of light-grown cucumber (cucumis sativus l. cv. aonaga-jibae) seedlings was studied. gibberellin a7 was used. at the saturation dosage, gibberellin-induced elongation was roughly proportional to the amount of the cotyledon retained. the cotyledon dependence of gibberellin-induced elongation was most marked when decotylization was done at the time of gibberellin treatment or at 24 hr after it. however, when the time of decotyl ... | 1980 | 25385960 |
| importance of rna synthesis whthin the lag phase preceding benzyladenine-induced growth of cucumber cotyledons in the dark. | changes in the rate of synthesis of cellular constituents were studied in detached cucumber cotyledons (cucumis sativus l. cv. ohio) after treatment with benzyladenine (ba). ba treatment stimulated rna and dna syntheses. the stimulation of rna synthesis occurred within the lag phase preceding ba-induced growth, while that of dna synthesis came during the growth. on the other hand, the stimulation by ba was not detected for protein and lipid syntheses. 5-fluorouracil (fu, 10(-3) m) plus thymidine ... | 1980 | 25385958 |
| ethylene production by chilled cucumbers (cucumis sativus l.). | chilling at 2.5 c accelerated the synthesis of 1-aminocyclopropane-1-carboxylic acid (acc) and c(2)h(4) production in cucumber fruit. skin tissue contained higher levels of acc and was more sensitive to chilling than was cortex tissue. accumulation of acc in chilled tissue was detected after 1 day of chilling and remained elevated even after c(2)h(4) production started to decline. these data suggest that acc synthesis is readily stimulated by chilling, whereas the system that converts acc to c(2 ... | 1980 | 16661538 |
| characterization of alpha-galactosidase from cucumber leaves. | two forms of alpha-galactosidase (alpha-d-galactoside galactohydrolase, e.c. 3.2.1.22) which differed in molecular weight were resolved from cucumis sativus l. leaves. the enzymes were partially purified using ammonium sulfate fractionation, sephadex gel filtration, and diethylaminoethyl-sephadex chromatography. the molecular weights of the two forms, by gel filtration, were 50,000 and 25,000. the 50,000-dalton form comprised approximately 84% of the total alpha-galactosidase activity in crude e ... | 1980 | 16661511 |
| in vivo pathway of oleate and linoleate desaturation in developing cotyledons of cucumis sativus l. seedlings. | exogenous [1-(14)c]oleic acid and [1-(14)c]linoleic acid were taken up and esterified to complex lipids by greening cucumber (cucumis sativus l.) cotyledons. both (14)c-labeled fatty acids were initially esterified to phosphatidylcholine prior to eventual accumulation in triacylglycerols and galactolipids. kinetic data suggest that esterification occurs prior to desaturation and that phosphatidylcholine is the initial site of both [(14)c]-oleate and [1-(14)c]linoleate esterification and of [1-(1 ... | 1980 | 16661499 |
| polyunsaturated fatty acid biosynthesis in cotyledons from germinating and developing cucumis sativus l. seedlings. | etiolated cucumis sativus l. cotyledons preferentially catabolized exogenous [1-(14)c]oleic acid and [1-(14)c]linoleic acid with relatively little incorporation into complex lipids or desaturation of the (14)c-labeled fatty acids. following a 16-hour exposure to light, the greening cotyledons efficiently desaturated the exogenous (14)c-labeled fatty acids. a small amount of oleate desaturation to linoleate was observed in etiolated tissue, but hardly any linoleate desaturation to alpha-linolenat ... | 1980 | 16661498 |
| occurrence and biosynthesis of glyoxysomal enzymes in ripening cucumber seeds. | glyoxysomal enzymes, being necessary during seed germination, are already synthesized at the stage of seed maturation. two stages of embryogenesis of cucumber seeds (cucumis sativus) were investigated. one was characterized by the presence of microbodies showing catalase and enoyl-coa hydratase activities. microbodies at a later stage contained, in addition, malate synthase and isocitrate lyase. the biosynthesis of three microbody components was followed in a pulse chase-labelling experiment whi ... | 1980 | 7450675 |
| 19s cytosolic malate synthase. a small pool characterized by rapid turnover. | a pool of 19s malate synthase was detected in the cytosol. this pool was separated from the microsomal and glyoxysomal malate synthase when cotyledons of germinating seed of cucumis sativus were fractionated. an early stage of seed germination was selected for our investigations, when 100s "microsomal" malate synthase was also present. 1) when l-[35s]methionine was applied in vivo to label cellular proteins the small pool of 19s malate synthase was found to contain the highest specific activity ... | 1980 | 7439887 |
| the control of food mobilization in seeds of cucumis sativus l. : iii. the control of protein degradation. | an analysis of the in vitro activities of proteolytic enzymes from cotyledons of germinating cucumber seeds has been carried out and the effects of protein degradation products on such activities monitored. aminopeptidase activity is substantially inhibited with either l-leucine or l-phenylalanine and trypsin activity with l-arginine. aminopeptidase activity was also markedly reduced in the presence of individual di- and tripeptides. of the peptides tested, however, only l-tryptophyl-l-phenylala ... | 1980 | 24306301 |
| molds in brined cucumbers: cause of softening during air-purging of fermentations. | softening of cucumbers in fermentations purged at high air-flow rates was caused by molds growing in the brined cucumbers, not in the brine. this conclusion is based on the following results: (i) no microorganisms were isolated in significant numbers from brines that caused softening of pasteurized brined cucumbers, (ii) no pectinolytic enzyme activities were produced in cucumber brines in the absence of cucumbers, (iii) the pickles in some air-purged fermentations became very soft without the a ... | 1980 | 16345619 |
| nmr study of the interaction of plastocyanin with chromium(ii) analogues of inorganic electron transfer reagents. | high resolution nuclear magnetic resonance spectroscopy has been used to examine the interaction of plastocyanins from french bean (phaseolus vulgaris) and cucumber (cucumis sativus) with three complexes--potassium hexacyano-chromate(iii), hexamminechromium(iii) nitrate and tris(1,10-phenanthroline)-chromium(iii) perchlorate--which are analogues of inorganic electron transfer reagents. the results indicate a high degree of specificity in the binding of these complexes and two binding sites on th ... | 1980 | 7388013 |
| individual quantitative rdna variation in three species of the cucurbitaceae family. | individual quantitative variation in rdna content within three species of the cucurbitaceae family has been studied by rrna/dna filter hybridization experiments. the results showed a 2.3-fold range of variation in the number of ribosomal cistrons per diploid cell in an ecballium elaterium natural population. this range of variation is compared with the smaller range observed in three cucumis sativus and in two cucurbita pepo varieties obtained as f1 hybrids between pure lines. | 1980 | 7437009 |
| a developmental study of photosystem i peripheral chlorophyll proteins. | an isolated "native" photosystem i (psi complex) contains three spectral populations of chlorophyll a antennae (mullet, burke, arntzen 1980 plant physiol 65: 814-822). it was hypothesized that nearly one-half of these antennae ( approximately 45 chl/p(700)) are associated with polypeptides of 21,500 to 24,500 daltons. the present study utilizes two developmental systems to verify this association.chloroplasts were isolated from a chl b-less barley mutant and from partially-developed cucumber cot ... | 1980 | 16661289 |
| opening of the hypocotyl hook in seedlings as influenced by light and adjacent tissues. | the influence of the cotyledons and apical bud and the root system on the light-induced opening of the hypocotyl hook of etiolated seedlings of gossypium hirsutum l., phaseolus vulgaris l., helianthus annuus l., ipomoea alla l., ipomoea sp., cucumis sativus l., linum usitatissimum l., hibiscus esculentus l., and raphanus sativus l. was studied. light stimulated the opening of hypocotyl hook in all cases, but the cotyledons and roots had different effects in different plants. generally, the prese ... | 1980 | 24309708 |
| chlorophyll determination in intact tissues using n,n-dimethylformamide. | photosynthetic pigments from etiolated cucumber (cucumis sativus var. beit alpha improved, hazera co., gedera) cotyledons were extracted by direct immersion of the intact cotyledons into the solvent n,n-dimethylformamide (dmf). the solvent is especially efficient when pigment concentration is low; time and tools are saved and the loss of pigment that usually occurs in more complicated extraction procedures is prevented. the specific absorption coefficient of chlorophyll a in dmf was also determi ... | 1980 | 16661217 |
| suspected foodborne carbamate pesticide intoxications associated with ingestion of hydroponic cucumbers. | in the period april 1--15, 1977, nine residents of one nebraska town experienced violent illnesses with short duration following ingestion of locally grown hydroponic cucumbers. despite a thorough investigation, the etiologic agent of illness was not determined. from july 16--25, 1978, a second similar outbreak occurred in an adjacent city. five individuals experienced illness similar to that which occurred in 1977, also following ingestion of hydroponic cucumbers grown at the same greenhouse in ... | 1980 | 7355886 |
| indoleacetaldehyde reductase of cucumis sativus l: kinetic properties and role in auxin biosynthesis. | indoleacetaldehyde reductase catalyzes the conversion of indoleacetaldehyde to indole ethanol in extracts of cucumis sativus l., with reduced pyridine nucleotide required as co-substrate. nadh and nadph result in markedly different enzyme behavior, as reflected in reaction kinetics and in responses to inhibitors and activators. it is not yet clear whether there are two separate enzymes, one specific for nadh and the other for nadph, or whether there is a single enzyme differentially influenced b ... | 1980 | 16661122 |
| separation and characteristics of galactose-1-phosphate and glucose-1-phosphate uridyltransferase from fruit peduncles of cucumber. | galactose-1-phosphate uridyltransferase (ec 2.7.7.10), responsible for the conversion of galactose-1-phosphate (gal-1-p) to uridine diphosphate galactose (udpgal) was examined in fruit peduncles of cucumis sativus l. two uridyltransferases (pyrophosphorylases), from i and ii, were partially purified and resolved on a diethylamino-ethyl-cellulose column. form i can utilize glucose-1-phosphate (glc-1-p), while form ii can utilize either gal-1-p or glc-1-p, with a preference for gal-1-p. form i was ... | 1981 | 24276942 |
| temperature effects on the activity of the alternative respiratory pathway in chill-sensitive cucumis sativus. | after 48 hours at 2 degrees c, hypocotyls from chill-sensitive cucumis sativus seedlings showed a burst of o(2) uptake. the alternative pathway became engaged to close to 45% full capacity during this postchilling respiratory burst. however, it only accounted for up to 50% of this increased respiratory o(2) uptake. by 24 hours after chilling, when the seedlings were fully recovered from visible symptoms of chilling injury, the flux through the alternative pathway was back to the level (about 10% ... | 1981 | 16662129 |
| rapid suppression of growth by blue light : biophysical mechanism of action. | the mechanism of the rapid inhibition of hypocotyl elongation by blue light was investigated in cucumber (cucumis sativus l.) and sunflower (helianthus annuus l.) seedlings by measuring the changes in turgor during the response. a special device, based on the resonance frequency principle, was built which permitted simultaneous and continuous measurements of both tissue rigidity (turgor) and growth rate on a single intact hypocotyl. the large decrease in growth rate following blue irradiation wa ... | 1981 | 16662124 |
| gas-liquid chromatographic method for determining oxamyl in peppers, tomatoes, and cucumbers. | a simple and fast gas-liquid chromatographic method has been developed to determine residues of oxamyl insecticide in peppers, tomatoes, and cucumbers. following sample extraction with ethyl acetate and cleanup on an alumina column, the compound is determined using a thermionic nitrogen-phosphorus detector. the limit of detection is 0.02 ppm based on 40 g sample. average recoveries for oxamyl at 0.025-1.0 ppm for all 3 products were 88-97%. | 1981 | 7287618 |
| studies on the mechanism of photoinhibition in higher plants: i. effects of high light intensity on chloroplast activities in cucumber adapted to low light. | cucumber plants (cucumis sativus l.), grown at low quantum flux density (120-150 microeinsteins per square meter per second) were photoinhibited by a three-hour exposure in air to ten times the light intensity experienced during growth. chloroplasts were isolated from photoinhibited and control leaves and the following activities determined: o(2) evolution in the presence of ferricyanide, photosystem i activity, noncyclic and cyclic photophosphorylation, and light-induced proton uptake. chloroph ... | 1981 | 16661828 |
| the control of food mobilisation in seeds of cucumis sativus l. : v. the effect of light on lipid degradation. | the degradation of neutral lipid and the development of lipase activity in cucumber cotyledons is stimulated by white light. malate synthase and isocitrate lyase activities show no stimulation. lipase activity and neutral lipid breakdown are also enhanced by red light, far-red light proving ineffective. far-red light reverses the effect of red light indicating the involvement of phytochrome in the control of lipase activity. although light stimulates neutral lipid degradation it appears that muc ... | 1981 | 24302321 |
| in vitro auxin binding to cellular membranes of cucumber fruits. | specific binding of 1-naphthaleneacetic acid (naa) to crude membrane preparations from cucumber (cucumis sativus l.) was demonstrated. this in vitro binding had a ph optimum of 3.75 and an equilibrium dissociation constant of 10 to 20 micromolar with 1250 picomoles binding sites per gram fresh weight. the naa-binding sites were pronase sensitive. the supernatant from the fruit partially inhibited the in vitro naa binding to fruit membranes. naa, 2-naphthoxyacetic acid, 3-indoleacetic acid, 2-4-d ... | 1981 | 16661764 |
| rapid suppression of growth by blue light: occurrence, time course, and general characteristics. | the inhibition of stem elongation in dark-grown seedlings by blue light was studied with marking techniques and with a high-resolution, growth-measuring apparatus. blue light rapidly suppresses growth in a variety of cultivated species. in some species, the inhibition persists only during the period of irradiation, after which time growth quickly returns to the high dark rate, whereas, in other species, the light response has an additional long-term component which lasts for at least several hou ... | 1981 | 16661718 |
| chloroplast biogenesis 34: spectrofluorometric characterization in situ of the protochlorophyll species in etiolated tissues of higher plants. | the fluorescence emission and excitation properties of protochlorophyll in etiolated cucumber (cucumis sativus l.) cotyledons and primary bean (var. red kidney) leaves were characterized at 77 k. contrary to previous studies, it appears that the short-wavelength protochlorophyll emission band consists of four fluorescent components, instead of only one nonphototransformable protochlorophyll. it was demonstrated that etiolated cucumber cotyledons synthesize and accumulate nontransformable protoch ... | 1981 | 16661643 |
| carcinogenicity of dichlorvos. | dichlorvos, 2,2-dichlorovinyl dimethyl phosphate, an organophosphate insecticide, is widely used for the control of agricultural, industrial, and domestic pests (fig. 1) [1]. dichlorvos is administered orally as an anthelmintic to swine, horses, cats, and dogs. it is applied by dermal application to cattle, goats, sheep, swine, and chickens to control fleas, flies, and mites. cucumbers, radishes, lettuce, and tomatoes are treated with dichlorvos in greenhouses. aerosols and strips are used for t ... | 1981 | 7009035 |
| host susceptibility of the papaya mosaic virus in sri lanka. | 75 plant species from 11 families were tested in sri lanka for their susceptibility to transferring the papaya mosaic virus. after inoculation with this virus, six species, cucurbita pepo, cucumis sativus, nicotiana tabacum, chenopodium amaranticolor, gomphrena globosa and lycopersicum esculentum, developed such symptoms, and after re-isolation from the host plant the virus again infected papaya plants. thus these species are possible alternate hosts of papaya mosaic virus in sri lanka. | 1981 | 7342959 |
| entrance and growth of lactic acid bacteria in gas-exchanged, brined cucumbers. | entrance of lactic acid bacteria into the interior of brined cucumbers was found to be greatly influenced by gas composition of the cucumbers before brining. exchange of the internal gas of fresh cucumbers with o(2) resulted in absorption of bacteria into the subsequently brined fruit within a few hours. bacteria were absorbed into nonexchanged cucumbers to a lesser extent. little bacterial absorption occurred in n(2)-exchanged cucumbers. stomata of the cucumber skin appeared to be a likely port ... | 1981 | 16345903 |
| a soil-free system for assaying nematicidal activity of chemicals. | a biological assay system for studying the nematicidal activity of chemicals has been devised using a model consisting of cucumber (cucumis sativus l. cv. long marketer) seedlings growing in the dispo(r) growth-pouch apparatus. meloidogyne incognita was used as the test organism. the response was quantified in terms of the numbers of galls produced. statistical procedures were applied to estimate the ed(50) values of currently available nematicides. this system permits accurate quantification of ... | 1981 | 19300800 |
| divergence, differential methylation and interspersion of melon satellite dna sequences. | melon (cucumis melo) satellite dna consists of two components, q and s, each with a buoyant density in cscl of 1.707 g/ml, but differing by 9 degrees c in "melting" temperature. these physical properties appear to be in contradiction, since both depend on g + c content. in order to resolve this anomaly, base compositions were directly determined for isolated fractions. the low-"melting" component s contains 41.8% g + c, with 6% of c present as 5-methylcytosine, whereas q dna contains 54% g + c, ... | 1981 | 6172117 |
| organization of highly repetitive satellite dna of two cucurbitaceae species (cucumis melo and cucumis sativus). | the prominent satellites of the cucurbitaceae cucumis melo (melon) and cucumis sativus (cucumber) have been characterized, in actinomycin/cscl gradients where the satellite sequences can be separated from ribosomal, organelle, and main band dna the location of the satellites is different indicating a different gc content. the purified satellite of c. melo is cut by hindiii into a repeat unit of 380 bp; alui digestion gives rise to two bands (about 80 and 220 bp in size). the hindiii repeat unit ... | 1982 | 6278425 |
| a comparative study in vitro of physiological activity of triterpene glycosides of marine invertebrates of echinoderm type. | 1. the cytostatic and antimicrobial activity of triterpene glycosides of 19 holothurian species of the pacific tropical zone has been studied. 2. it has been demonstrated that yeast and tumor cells display a comparable sensibility to the action of triterpene oligosides of sea cucumbers. 3. gram-positive and gram-negative bacteria are not sensible to the action of glycosides in doses to 500 mkg/ml. 4. triterpene glycosides-stichoposides, thelothurins and oligosides of holothuria of genus bohadsch ... | 1982 | 6128178 |
| effect of marine glycosides on adenosinetriphosphatase activity. | marine glycosides from the sea cucumbers actinopyga agassizi, holothuria atra, bohadschia argus, cucumaria fraudatrix, astichopus multifidus and thelenota ananas inhibit both na+-k+ atpase and mg2+-atpase of rat brain in vitro. the glycoside-cholesterol complex of these compounds does not influence atpase activity. asterosaponins from starfishes linckia guildingi and linckia laevigata possess a slight inhibiting effect. the triterpene glycosides from sea cucumbers are more powerful inhibitors th ... | 1982 | 6213068 |
| emission of hydrogen sulfide by leaf tissue in response to l-cysteine. | leaf discs and detached leaves exposed to l-cysteine emitted a volatile sulfur compound which was proven by gas chromatography to be h(2)s. this phenomenon was demonstrated in all nine species tested (cucumis sativus, cucurbita pepo, nicotiana tabacum, coleus blumei, beta vulgaris, phaseolus vulgaris, medicago sativa, hordeum vulgare, and gossypium hirsutum). the emission of volatile sulfur by cucumber leaves occurred in the dark at a similar rate to that in the light. the emission of leaf discs ... | 1982 | 16662510 |
| estimation of osmotic parameters accompanying zeatin-induced growth of detached cucumber cotyledons. | water potential (psi), the osmotic potential (psi(pi)), and the pressure potential (psi(p)) of detached cotyledons isolated from cucumis sativus l. cv marketer seedlings after 0, 1.5, and 3 days growth with and without zeatin were determined. from zero time to 3 days, cotyledons incubated without exogenous zeatin exhibited a slight decrease in psi (from -0.4 to -1.0 bars), while those grown with zeatin developed even more negative values (about -4 bars). both groups showed rising psi(pi) values ... | 1982 | 16662734 |
| evaluation of h secretion relative to zeatin-induced growth of detached cucumber cotyledons. | cytokinins promote expansion of cotyledons detached from seedlings of more than a dozen species. the zeatin-enhanced expansion of cucumber (cucumis sativus l. cv marketer) cotyledons was investigated. in addition, whether acid secretion is involved in wall loosening accompanying such accelerated growth was evaluated. for cotyledons abraded with carborundum or cut into either eight or 18 pieces, we detected no zeatin-enhanced acidification of the growth medium during growth periods of 3 days. mea ... | 1982 | 16662700 |
| isolation and estimation of cytokinins and cytokinin-containing transfer rnas from cucumis sativus l. var. guntur seedlings. | n(6)-(delta(2)-isopentenyl) adenosine antibodies were used for the isolation of free cytokinins and cytokinin-containing trnas from parts of cucumis sativus l. var. guntur seedlings and for the estimation of cytokinins in them. immobilized n(6)-(delta(2)-isopentenyl) adenosine antibodies retained trnas containing n(6)-(delta(2)-isopentenyl) adenosine and n(6)-(4-hydroxy-3-methylbut-2-enyl) adenosine with equal efficiencies. there were at least five cytokinins in the free form in cucumber seedlin ... | 1982 | 16662686 |
| in vitro synthesis of the chlorophyll isocyclic ring : transformation of magnesium-protoporphyrin ix and magnesium-protoporphyrin ix monomethyl ester into magnesium-2,4-divinyl pheoporphyrin a(5). | developing chloroplasts of cucumis sativus l., cv beit alpha which were incubated with either mg-protoporphyrin ix or mg-protoporphyrin ix monomethyl ester in darkness produced a partially phototransformable protochlorophyllide species that was tentatively identified as mg-2,4-divinyl pheoporphyrin a(5). s-adenosylmethionine stimulated mg-2,4-divinyl pheoporphyrin a(5) formation irrespective of the starting material used. in the case of mg-protoporphyrin ix monomethyl ester, this stimulation was ... | 1982 | 16662656 |
| resistance to injury by sulfur dioxide : correlation with its reduction to, and emission of, hydrogen sulfide in cucurbitaceae. | in cucurbitaceae young leaves are resistant to injury from acute exposure to so(2), whereas mature leaves are sensitive. after exposure of cucumber (cucumis sativus l.) plants to so(2) at injurious concentrations, illuminated leaves emit volatile sulfur, which is solely h(2)s. young leaves emit h(2)s many times more rapidly than do mature leaves. young leaves convert approximately 10% of absorbed [(35)s]so(2) to emitted [(35)s]h(2)s, but mature leaves convert less than 2%. these results suggest ... | 1982 | 16662511 |
| metabolism of exogenous indoleacetic acid to its amide conjugates in cucumis sativus l. | incubation of hypocotyl segments of light-grown cucumis sativus l. in 0.1 millimolar 3-indoleacetic acid for 16 hours led to the formation of indoleacetylaspartate and indoleacetylglutamate. there was no evidence for the formation of other conjugates of 3-indoleacetic acid with individual amino acids during the period from 4 to 48 hours of incubation. indoleacetylglutamate reached its maximum concentration after about 4 hours of incubation and indoleacetylaspartate after about 8 hours. these lev ... | 1982 | 16662461 |
| a simple method for the determination of resistance to gas diffusion in plant organs. | a simple method was developed for the determination of resistance coefficients for ethylene diffusion in plant tissues based on the kinetic analysis of the efflux of preloaded ethane gas. efflux curves were analyzed to obtain first-order rate constants and resistance coefficients. resistance coefficients determined by the ethane efflux and steady-state methods were found to agree well. employing the ethane efflux method, it was shown that over 97% of gas exchange of tomato (lycopersicum esculent ... | 1982 | 16662447 |
| evidence for an intracellular sulfur cycle in cucumber leaves. | h2s emission from cucumber (cucumis sativus l.) leaf discs supplied with l-cysteine in the dark is inhibited 80-90% by aminooxyacetic acid (aoa), an inhibitor of pyridoxal-phosphate dependent enzymes. exposure to l-cysteine in the light enhanced the emission of h2s in response to this sulfur source. turning off the light reduced the emission of h2s to the rate observed in continuous dark; turning on the light enhanced the emission of h2s to the rate observed in continuous light. therefore, in th ... | 1982 | 24276346 |
| effect of benzyladenine treatment duration on delta-aminolevulinic acid accumulation in the dark, chlorophyll lag phase abolition, and long-term chlorophyll production in excised cotyledons of dark-grown cucumber seedlings. | cotyledons excised from dark-grown cucumber (cucumis sativus l. cv. aonagajibai) seedlings were incubated in the dark with the cytokinin benzyladenine for different time periods. then, various greening parameters were examined, including protochlorophyll(ide) to chlorophyll(ide) photoconversion and delta-aminolevulinic acid accumulations in the dark, both triggered by a 5-minute red-light pulse.benzyladenine rapidly stimulates delta-aminolevulinic acid accumulation, protochlorophyll(ide) regener ... | 1982 | 16662270 |
| mechanism of action of the diphenyl ether herbicide acifluorfen-methyl in excised cucumber (cucumis sativus l.) cotyledons : light activation and the subsequent formation of lipophilic free radicals. | cucumber (cucumis sativus l.) cotyledons were sensitive to the diphenyl ether herbicide acifluorfen-methyl (afm); methyl 5-[2-chloro-4-(trifluoro-methyl)phenoxyl-2-nitrobenzoate. injury was detected by monitoring the efflux of (86)rb(+) from treated tissues after exposure to light (600 micro einsteins per meter(2) per second; photosynthetically active radiation).afm exhibited activity in green and etiolated tissues in the presence of both 1 micromolar 3-(3,4-dichlorophenyl)-1,1-dimethylurea (dcm ... | 1982 | 16662237 |