biologia plantarum

International journal on Plant Life established by Bohumil Němec in 1959

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Results 3871 to 3900 of 6170:

Detection of Ri T-DNA in transformed oilseed rape regenerated from hairy roots

M. Hrouda, Jana Dusbábková, J. Nečásek

Biologia plantarum 30:234-236, 1988 | DOI: 10.1007/BF02878767

A fertile plant with altered phenotype of oilseed rape (Brassica napus) spring cultivar HM-81 was regenerated from hairy root tumors incited by Agrobacterium rhizogenes 15834. Southern blot hybridization analysis revealed several copies of Tl and Tr-DNA of Ri plasmid.

Book review

Jarmila SolÁrovÁ

Biologia plantarum 30:299, 1988 | DOI: 10.1007/BF02878213

Book review

J. CHOD

Biologia plantarum 30:383, 1988 | DOI: 10.1007/BF02878195

ADP inhibition of the plasmalemma ATPase from Jerusalem artichoke tubers (Hèlianthus tuberosus L.)

G. Petel

Biologia plantarum 30:471, 1988 | DOI: 10.1007/BF02890519

The inhibitory effect of ADP on the plasma membrane ATPase from the parenchyma cells of Jerusalem artichoke (Helianthiis tuberosus L.) tubers was investigated in both physiological states (dormant or non-dormant). To begin with, several sources of ADP were employed, as many commercial ADP contain a variable and non-negligible amount of vanadate the inhibitory effect of which on plasmalemma ATPase is well known. By using vanadium-free ADP, it was possible to show that the plasma membrane ATPase was inhibited by ADP. Similar levels of inhibition were measured in dormant and non-dormant samples, showing that endogenous ADP is not responsible for the physiological regulation of ATPase activity in dormant and non-dormant materials.

Grain filling in relation to monocarpic senescence of wheat in varying source-sink ratios

A. K. Biswas, S. K. Mandal

Biologia plantarum 30:42-47, 1988 | DOI: 10.1007/BF02876422

Flag leaf removal at any stage of grain growth hastened senescence (reduction in chlorophyll content) of the sterile glumes whereas a removal of the latter did not alter senescence of the former. Kernel mass, grain mass per ear, harvest index and sink activity reduced more conspicuously by the removal of glumes than by the flag leaf removal. Removal of grains hastened senescence of the glumes only, although protein content increased at a later grain removal in the majority of source organs. Moisture contents of the developing grains were mostly reduced by the removal of either the flag leaf or the glumes, though flag leaf removal at anthesis affected it the most. Protein levels of the developing grains reduced at harvest only when the glumes were removed at anthesis but sugar levels in later phases always decreased irrespective of the time of removal and nature of the source organs.

Size and compositional heterogeneity of seeds in the winged bean pod (Psophocarpus tetragonolobus (L.)DC)

T. Kamala Devi, K. Sree Kumar

Biologia plantarum 30:142, 1988 | DOI: 10.1007/BF02878485

Differently positioned seeds in the mature pod of winged bean (Psophocarpus tetragonolobus (L.) DC) differ in mass and content of total protein and phosphorus and starch.

Book review

C. Záruba

Biologia plantarum 30:218, 1988 | DOI: 10.1007/BF02878762

Hexokinases of tobacco leaves: Subcellular localization and characterization

Milada ŠindelÁŘovÂ, L. ŠindelÂr

Biologia plantarum 30:275-284, 1988 | DOI: 10.1007/BF02878208

Subeellular localization of the enzymes which phosphorylate hexoses was studied in photosynthesizing tobacco leaves by means of differential centrifugation and centrifugation in sucrose gradient. More than 80 % of the total hexokinase activity of leaf tissues were found to be associated with the particulate fraction of mitochondria; however, the ratio of the particulate hexokinase fraction to the soluble fraction was influenced by the extraction medium applied. The particulate hexokinases showed a high affinity to glucose (Km = 26.8 μM) and a relatively low affinity to fructose (Km = 17.6 mM). They had a broad pH optimum, because 81 % of the phosphorylating activity obtained for glucose and 75 % of the activity obtained for fructose occurred in pH range from 7.9 to 9.1 (Tris-HCl buffer). The hexokinases were Mg2+ dependent with the highest activity occurring at equimolar Mg2+ and ATP concentrations. Their activity was enhanced by KC1, NaCl, and (NH4)2SO4 at 30 to 120 mM concentrations.

Effect of high boron levels on growth and some metabolic activities of the halotolerantdunaliella tertiolecta

A. M. Ahmed, M. A. Zidan, M. S. Adam

Biologia plantarum 30:357-361, 1988 | DOI: 10.1007/BF02878190

Growth of Dunaliella tertiolecta was retarded when the alga was exposed to high boron (B) concentrations between 50 and 200 g m-3. Photosynthetic oxygen evolution as well as respiratory oxygen uptake were significantly suppressed with the rise of B concentration. Similarly the contents of chlorophyll, glycerol, lipid and proteins were lowered, while that of saccharides was raised.

Sulphate ion influx and efflux inhydrodictyon reticulatum

Renata Rybová, Ludmila Nešpůrková, K. Janáček

Biologia plantarum 30:440, 1988 | DOI: 10.1007/BF02890514

Sulphate ion is accumulated in the cells of the algaHydrodidyon reticulatum to a concentration approximately 30 mmol 1-1. The rate of SO4 2- uptake is increased markedly in the light, however, the effect is observable only after the cells have been kept in the light for about one hour. Uptake of sulphate is strongly inhibited by phosphorylation uncouplers and also by DIDS. The two-phase sulphate uptake kinetics, reported earlier was confirmed in experiments in which competition with phosphate anion was tested. Phosphate competes with sulphate only in the range of higher substrate concentrations (from 0.2 mmol 1-1) and does not affect the system which works at low substrate concentrations. Efflux of SO4 2- is very slow; the reason of the flux hindrance is not yet known.

Antimutagenic effects of diethyldithiocarbamate towards maleic hydrazide- and N-nitrosodiethylamine-induced mutagenicity in theTradescantia mutagenicity assay

T. Gichner, J. Velemínský, R. Rieger

Biologia plantarum 30:14, 1988 | DOI: 10.1007/BF02876417

InTradescantia, clone 4430, diethyldithiocarbamate (DEDTC) markedly decreased the frequency of somatic mutations induced by maleic hydrazide (MH) and N-nitrosodiethylamine (NDEA). In contrast, DEDTC had no such effect on N-methyl-N-nitrosourea-induced mutagenesis. The putative degradation and conversion products of MH (maleic acid diamide, succinic acid, maleic acid, lactic acid and hydrazine) exhibited no mutagenic activity in theTradescantia mutagenicity assay.

Effect of GA3 and BAP on respiration, phosphate uptake and metabolism in foliar discs of Pelargonium zonale after ageing

J. Beraud, M. Penot

Biologia plantarum 30:111, 1988 | DOI: 10.1007/BF02878478

Respiration rate of foliarPelargonium discs was insensitive to ageing. The addition of BAP or GA3 to the ageing medium did not produce any effect.
The presence of GA3 or BAP in the ageing medium induced an increase (27 %) or a decrease (45 %) of the phosphate uptake. The analysis of phosphorylated compound labelling showed that these two hormones decreased32P incorporation in the non-acid soluble fraction and increased32P incorporation in the acid soluble organic fraction. GA3 and BAP had little effect on the distribution of radioactivity between the different acid soluble compounds, but they increased the ATP level.
These results suggest that both GA3 and BAP increase the basal metabolism, but they seem to act differently on the development of the uptake mechanism during ageing.

Book review

J. Krekule

Biologia plantarum 30:198, 1988 | DOI: 10.1007/BF02878757

Proton extrusion by Leaf Discs ofVicia faba L.: Influence of inhibitors and phytohormones on H+ extrusion†

U. Petzold, I. Dahse, P. Jacob

Biologia plantarum 30:252-259, 1988 | DOI: 10.1007/BF02878203

The present investigations were designed to elucidate the linkage of medium acidification to metabolism and to study the influence of phytohormones (IAA, ABA) and fusieoccin (FC) on H+ extrusion from peeled leaf tissue of Vicia faba. H+ release, which was sensitive to the metabolic inhibitors sodium azide, vanadate, DCCD, and cycloheximide, was promoted by 5 to 50 μM IAA and 10 μ FC, but transiently diminished by 10 μM ABA. FC was a much more powerful inducer of H+ extrusion than IAA. Other weak acids such as acetate and citrate had no effect on H+ extruding activity of Vicia leaf tissue indicating that the IAA effect is specific. These results support the view that IAA and ABA control of cell growth can be attributed entirely to a modulation of H+ pump activity.

Book review

T. Gichner

Biologia plantarum 30:337, 1988 | DOI: 10.1007/BF02878185

Nutritional changes induce xylogenesis in callus ofHaplopappus gracilis (NUTT.) A. Gray

Wiesława Kutternozińska, Lucyna Wajda, W. Korohoda

Biologia plantarum 30:409, 1988 | DOI: 10.1007/BF02890508

Xylogenesis was induced in cultures of calli ofHaplopappus gracilis (NUTT.) A. Gray by metabolic shocks brought about by changes in nutrition. Xylogenesis was observed to occur in response to three changes in callus nutrition, caused by the following modifications of Eriksson's nutrient medium and culture conditions: i) omission of sucrose in the medium for 3 to 6 days and then transfer of the calli onto complete Eriksson's medium; ii) replacement of sucrose by 0.36*mol l-1 xylose for the whole culture period; iii) omission of nitrogen sources(i.e. glycine and NH4NO3 omission and replacement of KNO3 with equimolar KCI) for the whole culture period.
The induction of xylogenesis in response to nutritional stress inH. gracilis can be used as a suitable model system for research concerning plant cell differentiation.

The bacterial wilt, uptake of phosphate, and phosphate ester levels in the resistant and susceptible alfalfa plants

I. Hanker, Anna Kůdelová

Biologia plantarum 30:63-73, 1988 | DOI: 10.1007/BF02876428

7 days or 7 weeks old alfalfa plants (Medicago sativa L.), susceptible (S) and resistant (R) to bacterial wilt, were inoculated withCorynebacterium michiganense pv.insidiosum and on day 8 and 15 after inoculation the levels of acid-soluble phosphate esters (P-esters) were determinated by means of32P labelling in the shoots or roots. The most significant changes were recorded in the roots of the older R plants grown in full Knop nutrient solutions on day 8 after inoculation. The marked reduction of inorganic phosphate (P1) uptake by whole R plants is accompanied by a decrease in the levels of fructose-l, 6-bisphosphate (Fru-P2), glucose-6-phosphate (Glc-6-P), fructose-6-phosphate (Fru-6-P), adenosine mono-, and diphosphate (AMP and ADP), phosphorylcholine (P-choline) and a proportional increase in the level of P1. In the S plants, infection affected neither P1 uptake nor P1 proportions. In the plants grown after inoculation in diluted Knop's solutions (0.147 mM KH2PO4), infection induced a reduction of the radial transport of P1 to the segments of R roots whereas a reduction of the levels was only recorded in some P-esters [AMP, ADP, dihydroxyacetone phosphate (DHAP), and P-choline, but no decrease of Fru-P2, Glc-6-P and Fru-6-P]. In the S plants, P1 transport and the levels of P-esters were increased by the infection. P1 transport exhibited considerable metabolic dependence (DNP, DCCD). Bacterial infection probably had no influence on the activity of the plasma membrane ATPases.

Book review

Ingrid Tichá

Biologia plantarum 30:178, 1988 | DOI: 10.1007/BF02878752

Book review

M. Marek

Biologia plantarum 30:236, 1988 | DOI: 10.1007/BF02878768

Effect of kinetin on interspecific crosses inBrassica

N. Sarla

Biologia plantarum 30:305-308, 1988 | DOI: 10.1007/BF02878215

Application of kinetin to four interspecific crosses in Brassica, either singly or in combination with NAA, resulted in larger length and retention time of ovaries, increased frequency of ovules with embryos and aided embryo development.

Overcoming interspecific incompatibility in the crossBrassica campestris ssp.japonica xBrassica oleracea var.botrytis using irradiated mentor pollen

N. Sarla

Biologia plantarum 30:384-386, 1988 | DOI: 10.1007/BF02878196

The cross B. campestris ssp. japonica x B. oleracea var. botrytis fails due to incompatibility barrier at the stigma. To realize this cross, irradiated compatible pollen (mentor pollen) was used before the incompatible pollination. The presence of mentor pollen stimulated the incompatible pollen to germinate and effect fertilization and seed set. One hybrid was thus obtained. Most of the seeds were inviable. Of the 5 plants raised one was a hybrid and 4 resembled the female parent.

On the economy of plant form and function. Proceedings of the Sixth Maria Moors Cabot Symposium, "Evolutionary Constraints on Primary Productivity: Adaptive Patterns of Energy Capture in Plants"

Javrmila Solárová

Biologia plantarum 30:474, 1988 | DOI: 10.1007/BF02890520

Changes in the content of some phenolic compounds in connection with flower- and fruit-formation of vine

D. Lilov, Yordanka Angelova

Biologia plantarum 29:34-37, 1987 | DOI: 10.1007/BF02902313

The quantitative changes of chlorogenic acid in shoots and leaves of two groups of grape vines differing in their flower- and fruit-formation have been studied. It was established that in most cases the acid level was lower in both shoots and leaves of grape vines with suppressed growth and intensified generative processes. The results obtained suggest that the lower content of chlorogenic acid is related to the reduced growth of shoots and acceleration of generative processes.

The action of the testa upon the germination of seeds ofCucumis anguria L.

V. J. M. Cardoso, G. M. Felippe

Biologia plantarum 30:48-52, 1988 | DOI: 10.1007/BF02876423

In negatively photoblastic seeds of Cucumis anguria L. the scarification of micropyle overcame the inhibitory effect of "white light ", although far-red radiation inhibited the germination in both intact and scarified seeds. The moistened testa powder transmitted more far-red than red radiation. Thus the testa could act as a filter of radiation and maintain a high far-red/red ratio at the photosensitive site of the embryo, which must be localized near the micropyle.

The effect of potassium on germinating wheat embryos at different viability levels

L. Petruzzelli

Biologia plantarum 30:147-151, 1988 | DOI: 10.1007/BF02878486

The effect of potassium administration in early germination of wheat (Triticum durum L., cv. Appulo) was studied by incubating isolated embryos at different viability levels with 1 mM KC1. The stimulation of germination and growth in aged embryos by K+ was accompanied by a significant increase in (3H) leucine incorporation into protein and in phospholipid synthesis as evidenced by TLC analysis of embryo phospholipids extracted after 24 h of imbibition. The metabolic improvement mediated by the cation would in turn repair aging damage occurring at subcellular sites including membranes.

Composition of the walls of stem and leaves of vitrifying carnation

C. Kevers, R. Goldberg, J. Chu-Ba, Th. Gaspar

Biologia plantarum 30:219-223, 1988 | DOI: 10.1007/BF02878763

Vitrification of stem explants of carnation was brought about by culturing in liquid medium. Cellulose and lignin levels were decreased in vitrified stems and leaves. Isolated cell walls of vitrified tissues were also characterized by low calcium content, low Ca2+/uronic acids ratio, low ratio of uronic acids to neutral sugars due to higher amounts of the latters. All these characteristics may account for the high wall plastic potential previously measured in vitrifying internodes.

Book review

Ingbid Tichá

Biologia plantarum 30:284, 1988 | DOI: 10.1007/BF02878209

Pyruvate kinase, an enzyme subject to regulation inDioscorea alata

U. Oluoha

Biologia plantarum 30:362-372, 1988 | DOI: 10.1007/BF02878191

Different species of yam tubers were examined for the presence of pyruvate kinase and phosphatase activities, Pyruvate kinase was purified 25 fold with a yield of 50 %. using ammonium sulphate precipitation and ion exchange chromatography on DEAE-Sephadex. Partially purified enzyme showed normal Michaelis-Menten kinetics. However, pyruvate kinase from crude extract of dormant yam tuber showed slight sigmoid response towards phosphoenol-pyruvate and magnesium and to a certain extent ADP. The enzyme is activated by AMP and inhibited by ATP and citrate in both crude and partially purified preparations. Further studies on the effect of energy charge on the enzyme strongly suggest that pyruvate kinase from D. alata is a regulatory enzyme. No evidence was found for the presence of more than one pyruvate kinase in germinating D. alata tuber. With the exception of D. dumentorum, all the other three species of yams studied contain very little or no detectable phosphatase activity during dormancy. However, phosphatase activity increased during germination in all the species, thus excluding the use of sprouting yam tubers for kinetic study of pyruvate kinase.

Sulphate uptake by leaf mesophyll and bundle sheath cells of maize plants

C. Passera, M. Ferretti

Biologia plantarum 30:451, 1988 | DOI: 10.1007/BF02890515

Uptake of35S-sulphate by bundle sheath strands (BSC) from leaves of maize plants (Zea mays L. ev. Dekalb L 72 A) was higher than that by isolated mesophyll protoplasts (MC) of maize. Ion uptake followed the Michaelis-Menten kinetic satuiation curves. SO2 4-uptake increased after addition of malate, NADPH, malate + NADP+ to BSC suspensions, but not to MC susp: nsions.

Effect of season of collection of explants on micropropagation ofChrysanthemum morifolium

R. N. Prasad, H. C. Chaturvedi

Biologia plantarum 30:20-24, 1988 | DOI: 10.1007/BF02876418

The season of collection of shoot tips from field-grown plants ofChrysanthemum morifolium cv. Birbal Salmi was found to be crucial for their proliferation and establishment of plants in vitro. Shoot tips collected only during the period of March to April proliferated and survived. Shoot apices and segments of leaf, stem (nodal und internodal) and root, excised from aseptically established plants, were cultured on Murashige and Skoog's medium supplemented with different concentrations and combinations of Kn, BAP, IAA and NAA. A maximum number of 9 off-shoots differentiated, without intervening callus formation, from a shoot tip in a treatment containing 1.5 mg l-1 BAP and 0.1 mg-1 NAA in 60 days. A single-node stem segment produced less shoots in the same treatment. Other kinds of expiants produced only callus. About 2-cm-long shoots, excised from cultures of proliferating shoots, were rooted 100 %, acclimatized and grown in soil. They grew normally and flowered true-to-type.

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