Pavel Šiffel - † 12^th July 2003

J. Šantrůček

Biologia plantarum 2004, 48:I | DOI: 10.1023/B:BIOP.0000024316.17713.ce

Changes in Peroxidases and Catalase Activity During in vitro Rooting

A.N. Molassiotis, K. Dimassi, G. Diamantidis, I. Therios

Biologia plantarum 2004, 48:1-5 | DOI: 10.1023/B:BIOP.0000024267.68394.96

Enzyme changes in non-rooted (treated with Fe-EDTA) and rooted (treated with Fe-EDDHA) stems of rootstock GF-677 (Prunus amygdalus×P. persica) during adventitious root formation in vitro have been recorded. The first roots appeared approximately after 12 d on the rooting medium. By contrast to non-rooted stems, rooted stems showed a maximum of soluble peroxidase activity on the 9^th day, of ionically bound peroxidase to cell wall on the 6^th and 12^th day and of catalase on the 6^th and the 15^th day. A time course study of changes of soluble peroxidases isoenzymes showed that there...

Breckle, S.-W.: Walter's Vegetation of the Earth. The Ecological Systems of the Geo-Biosphere

J. Gloser

Biologia plantarum 2004, 48:6 | DOI: 10.1023/B:BIOP.0000024317.84235.0d

Culture Tube Closure-Type Affects Potato Plantlets Growth and Chlorophyll Contents

A. Chanemougasoundharam, D. Sarkar, S.K. Pandey, F. Al-Biski, O. Helali, J.S. Minhas

Biologia plantarum 2004, 48:7-11 | DOI: 10.1023/B:BIOP.0000024268.20248.33

The effect of different hermetic and non-hermetic closure-types (aluminum foil, cotton bung, cotton plug, polypropylene cap and Steristopper) on potato (Solanum tuberosum L.) plantlets growth and chlorophyll contents was studied in three genotypes belonging to different maturity groups. Plantlets grown in culture tubes closed with aluminum foils and polypropylene caps had higher fresh mass and shoot length, but lower chlorophyll contents, higher senescence index and various morphological abnormalities. Non-hermetic closures like cotton plugs and Steristoppers were found optimum for plant growth without any morphological abnormalities....

Schekman, R., Goldstein, L., Rossant, J. (ed.): Annual Review of Cell and Developmental Biology. Volume 19

T. Gichner

Biologia plantarum 2004, 48:12 | DOI: 10.1023/B:BIOP.0000024318.21873.39

Rapid in vitro Regeneration of Sesbania drummondii

S.B. Cheepala, N.C. Sharma, S.V. Sahi

Biologia plantarum 2004, 48:13-18 | DOI: 10.1023/B:BIOP.0000024269.72171.42

This paper describes rapid propagation of Sesbania drummondii using nodal explants isolated from seedlings and young plants. The nodal segments proliferated into multiple shoots on Murashige and Skoog's (MS) medium supplemented with 22.2 μM benzyladenine. MS medium containing 2.2 and 4.5 μM thidiazuron induced 5 - 6 shoots per stem node from 3-month-old plants. Nodal explants when cultured on MS medium containing combinations of benzyladenine (8.8 and 11.1 μM) and indole-3-butyric acid (0.24 - 2.46 μM) or indole-3-acetic acid (0.28 - 2.85 μM) gave lesser number of shoots. Callus induced on cotyledonary explants when subcultured...

Genotype- and Sex-Specific Protocols for in vitro Micropropagation and Medium-Term Conservation of Jojoba

R.K. Tyagi, S. Prakash

Biologia plantarum 2004, 48:19-23 | DOI: 10.1023/B:BIOP.0000024270.02186.1f

Nodal explant cultures from field-grown five jojoba genotypes (EC 99690, EC 99692, EC 99692, EC 267779 and EC 171284; male and female plants), could be established on Murashige and Skoog (MS) medium. The nodal explants of different genotypes as well as sex elicited differential requirements of N⁶-benzyladenine (BA) for optimum shoot regeneration and medium-term conservation. Female nodal explants of EC 99692 produced maximum shoots (10 shoots per explant) followed by male of EC 171284 (9.3 shoots per explant) on MS + 10 μM BA. The pulse treatment of 50 μM indole-3-butyric acid for 20 min caused in vitro rhizogenesis in 44 -...

Laimer, M., Rücker, W. (ed.): Plant Tissue Culture, 100 years since Gottlieb Haberlandt

J. Krekule

Biologia plantarum 2004, 48:24 | DOI: 10.1023/B:BIOP.0000024319.66103.22

Transformation of Indica Rice Through Particle Bombardment: Factors Influencing Transient Expression and Selection

K.B.R.S. Visarada, N.P. Sarma

Biologia plantarum 2004, 48:25-31 | DOI: 10.1023/B:BIOP.0000024271.38723.a6

Embryogenic, friable and small (ca. 3 mm) calli showed optimum gus expression and were best suited for selection during genetic transformation of rice through particle bombardment. Through prolonged culture of mature seeds on original callus induction medium, this type of calli could be produced in large numbers across several elite rice genotypes. To minimize the non-transformed escapes 50 mg dm^-3 hygromycin and 8 mg dm^-3 glufosinate ammonium were found to be critical during selection. Addition of selection marker during regeneration was essential. Regular and frequent (every 15 d) transfer of calli to fresh selection...

Whitelock, L.M.: The Cycads

J. Ďurkovič

Biologia plantarum 2004, 48:32,40 | DOI: 10.1023/B:BIOP.0000024320.52092.32

Changes in Antioxidative Protection in Bean Cotyledons During Natural and Continuous Irradiation-Accelerated Senescence

D. Procházková, N. Wilhelmová

Biologia plantarum 2004, 48:33-39 | DOI: 10.1023/B:BIOP.0000024272.98338.5b

We employed continuous irradiation (CL) for induction of premature senescence caused by enhanced production of reactive oxygen species. As a model plant we used bean (Phaseolus vulgaris L. cv. Jantar) cotyledons because they have well defined and a quite short life span. Senescence of bean cotyledons induced by CL progressed more rapidly than natural senescence: the life span of CL cotyledons was 13 d compared to 16 d in controls (C). Chl content was significantly lower in 10- and 13-d-old CL plants than in C plants and the change with age was not statistically significant. Activities of all antioxidative enzymes declined either with senescence...

Antioxidant Enzyme Isoforms on Gels in Two Poplar Clones Differing in Sensitivity After Exposure to Ozone

R. Bernardi, C. Nali, P. Ginestri, C. Pugliesi, G. Lorenzini, M. Durante

Biologia plantarum 2004, 48:41-48 | DOI: 10.1023/B:BIOP.0000024273.35976.cb

The effect of acute ozone (O₃) fumigation on isozyme patterns of superoxide dismutase (SOD), peroxidase (POD) and ascorbate peroxidase (APX) in mature (ML) and young leaves (YL) of two poplar clones, contrasting in O₃-sensitivity was analysed. Untreated leaves of both the O₃-sensitive (O₃-S) clone Eridano of Populus deltoides×P. maximowiczii and the O₃-resistant (O₃-R) clone I-214 of P.×euramericana showed four distinct SOD isoforms with a relative mobility (R_f) of 0.54 (MnSOD), 0.60 (Cu/ZnSOD), 0.65 (unidentified), and 0.71 (Cu/ZnSOD). After O₃-fumigation...

Antioxidant Systems in Ripening Tomato Fruits

K. Mondal, N.S. Sharma, S.P. Malhotra, K. Dhawan, R. Singh

Biologia plantarum 2004, 48:49-53 | DOI: 10.1023/B:BIOP.0000024274.43874.5b

Two cultivars of tomato (Lycopersicon esculentum Mill.), Selection-7 (shelf life 7-8 d) and ARTH-3 (shelf life 14-15 d) were analyzed for oxidative stress and the antioxidant enzyme system at different stages of fruit ripening. The results presented here suggest that during the early stages of fruit ripening, efficient antioxidant system protects the tomato fruits against the damaging effect of progressive oxidative stress. At later stages, however, oxidative damage occurs due to decreased activities of the ROS scavenging enzymes.

Calmodulin from Pharbitis nil: Purification and Characterization

K. Jaworski, A. Szmidt-Jaworska, A. Tretyn, J. Kopcewicz

Biologia plantarum 2004, 48:55-60 | DOI: 10.1023/B:BIOP.0000024275.66196.d9

A protein, identifiable as calmodulin (CaM), has been isolated from the seedling tissue of Pharbitis nil. The method has been developed to isolate a high quality protein from plant tissue containing the high content of polyphenols. This protein was relatively heat-stable and bound to hydrophobic resin in calcium-dependent manner. It was recognized by the antibody against pea and carrot, but did not bind to antibody against Dictyostelium discoideum. This protein had M_r of 15 kDa and 18.5 kDa in the presence and absence of Ca₂₊, respectively, and was able to stimulate calmodulin-deficient cAMP phosphodiesterase. Based...

Interactive Effects of Thiourea and Phosphorus on Clusterbean Under Water Stress

U. Burman, B.K. Garg, S. Kathju

Biologia plantarum 2004, 48:61-65 | DOI: 10.1023/B:BIOP.0000024276.03834.8d

Effects of phosphorus and thiourea application (either alone or in combination) were studied on clusterbean (Cyamopsis tetragonoloba Taub.) plants subjected to water stress by withholding irrigation at pre- and post-flowering stages in pot culture trial. Water stress significantly decreased shoot water potential, relative water content of leaves, net photosynthetic rate, contents of total chlorophyll, starch and soluble proteins as well as nitrate reductase activity at both the growth stages. Application of phosphorus and thiourea or combined application increased most of these parameters. Results revealed synergistic effects of P and thiourea...

Effects of Nitrate Nutrition on Nitrogen Metabolism in Cassava

J.L. Cruz, P.R. Mosquim, C.R. Pelacani, W.L. Araújo, F.M. DaMatta

Biologia plantarum 2004, 48:67-72 | DOI: 10.1023/B:BIOP.0000024277.51293.02

Two experiments were conducted independently with plants of cassava (Manihot esculenta Crantz) growing in sand with nutrient solutions with four nitrate concentrations (0.5, 3, 6 or 12 mM). In leaves, nitrate-N was undetectable at the low nitrate applications; total-N, ammonium-N, amino acid-N, reduced-N and insoluble-N all increased linearly, while soluble proteins did it curvilinearly, with increasing nitrate supply. In contrast, soluble-N did not respond to N treatments. Total-N and soluble proteins, but not nitrate-N or ammonium-N, were much higher in leaves than in roots. Plants grown under severe N deficiency accumulated ammonium-N and...

Effect of High Temperature on Protein Expression in Strawberry Plants

N.A. Ledesma, S. Kawabata, N. Sugiyama

Biologia plantarum 2004, 48:73-79 | DOI: 10.1023/B:BIOP.0000024278.62419.ee

Strawberry plants (Fragaria×ananassa Duch.) cvs. Nyoho and Toyonoka were exposed to temperatures of 20, 33, and 42 °C for 4 h, and protein patterns in leaves and flowers was analyzed by 2-dimensional polyacrylamide gel electrophoresis and immunoblotting. In leaves and flowers of both cultivars, the content of most proteins decreased, but a few new proteins appeared in response to heat stress. These heat shock proteins (Hsps) were detected in the range of 19 - 29 kDa in leaves, and 16 - 26 kDa in flowers. The intensity of a 43 kDa protein spot increased in response to heat stress in Nyoho flowers, but not in Toyonoka flowers. The peaHsp17.7...

Thermotolerance of Pearl Millet and Maize at Early Growth Stages: Growth and Nutrient Relations

M. Ashraf, M. Hafeez

Biologia plantarum 2004, 48:81-86 | DOI: 10.1023/B:BIOP.0000024279.44013.61

Thermotolerance of pearl millet (Pennisetum glaucum cv. ICMV-94133) and maize (Zea mays cv. Golden) was assessed at germination and vegetative stage. Final percentage of germinated seeds and rate of germination (number of days to 50 % germination) decreased due to high temperature (45 °C) similarly in the both species. In contrast, at the vegetative stage, high temperature (38/27 °C) caused a significant reduction in shoot dry mass of maize, whereas this attribute remained almost unchanged in pearl millet. Relative growth rate and net assimilation rate (NAR) increased significantly in pearl millet due to high temperature, but in contrast,...

The Regulation of the Plasma Membrane Redox System and H⁺-transport in Adaptation of Reed Ecotypes to Their Habitats

K.-M. Chen, H.-J. Gong, S.-M. Wang, C.-L. Zhang

Biologia plantarum 2004, 48:87-92 | DOI: 10.1023/B:BIOP.0000024280.36595.99

The redox system and H⁺-transport activities in the plasma membranes from two ecotypes of reed (Phragmites communis Trin.), named swamp reed (SR) and dune reed (DR) according to their habitats, were investigated. Compared to the SR, the DR possessed the very high rates of NADH oxidation and Fe(CN)₆^3- and EDTA-Fe³⁺ reduction when NADH was taken as the electron donor. As NADPH was an electron donor, the rate of NADPH oxidation was also significantly higher in the DR than that in the SR. In addition, the H⁺-transport activity in the plasma membranes was also significantly higher in the DR than...

Study of Resistance of Musa acuminata to Fusarium oxysporum using RAPD markers

M.A. Javed, M. Chai, R.Y. Othman

Biologia plantarum 2004, 48:93-99 | DOI: 10.1023/B:BIOP.0000024281.85427.6d

Suckers collected from different populations of Musa acuminata ssp. malaccensis were found to be highly resistant to race 4 of Fusarium oxysporum f. sp. cubense (FOC) suggesting that local wild banana populations co-evolved with the pathogen. Seedlings from these wild banana plants segregated for resistance to the pathogen. The infected seedlings were characterized based on external and internal symptoms and the variable response to FOC was mainly due to the genetic factors. Using the technique of random amplified polymorphic DNA (RAPD), 96 major amplification products from 15 primers were identified. Only 10 out of 96 markers...

Shoot Regeneration in Four Begonia Genotypes

F.J. Espino, R. Linacero, J. Rueda, A.M. Vázquez

Biologia plantarum 2004, 48:101-104 | DOI: 10.1023/B:BIOP.0000024282.01087.a3

In vitro regeneration of four Begonia genotypes, B. semperflorens, B. rex, B.×elatior, and hybrid of Begonia with unknown parents 'Tiger' was carried out starting from leaf and petiole segments as explants. Five Murashige and Skoog's derived media were tested, three of them supplemented with α-naphthaleneacetic acid (NAA) and 6-benzyladenine (BA), and the other two with NAA and kinetin (KIN) in different concentrations. Shoot regeneration was preferentially induced on the BA containing media, quantitative differences being observed among explants and genotypes.

Growth, Water Content, and Proline Accumulation in Drought-Stressed Callus of Date Palm

J.M. Al-Khayri, A.M. Al-Bahrany

Biologia plantarum 2004, 48:105-108 | DOI: 10.1023/B:BIOP.0000024283.74919.4c

This study was conducted to examine the response of date palm (Phoenix dactylifera L., cvs. Barhee and Hillali) calli to water stress. Callus derived from shoot tip explants was inoculated in liquid Murashige and Skoog medium containing 10 mg dm^-3α-naphthaleneacetic acid, 1.5 mg dm^-3 2-isopentenyladenine, and 0 to 30 % (m/v) polyethylene glycol (PEG 8000) to examine the effect of water stress. After 2 weeks, callus growth, water content, and proline accumulation were assessed. Increasing water stress caused a progressive reduction in growth as expressed in callus fresh mass, relative growth rate, and index of tolerance....

In vitro Shoot Bud Differentiation from Leaf Segments of Achras sapota

S.D. Purohit, A. Singhvi, R. Nagori

Biologia plantarum 2004, 48:109-112 | DOI: 10.1023/B:BIOP.0000024284.84740.75

Direct shoot bud differentiation was achieved in leaf segments of Achras sapota cv. Cricket Ball inoculated on Schenk and Hildebrandt's medium supplemented with 5.0 μM thidiazuron and 8.88 μM benzylaminopurine. Leaves from middle part of the shoots and segments obtained from middle portion of leaf showed highest potential to regenerate shoot buds. Histological examination of developing shoot buds showed their de novo regeneration with clear vascular connection with the mother tissues.

Detection of Intra-Clonal Genetic Variability in Vegetatively Propagated Tea Using RAPD Markers

M. Singh, J. Saroop, B. Dhiman

Biologia plantarum 2004, 48:113-115 | DOI: 10.1023/B:BIOP.0000024285.44356.99

The role of random amplified polymorphic DNA (RAPD) markers in detecting intra-clonal genetic variability in vegetatively propagated UPASI-9 clone of tea (Camellia sinensis) was studied. Twenty five decamer primers were used, of which three did not amplify, three gave single bands and the rest of nineteen primers generated upto twelve bands (an average of 6.3 bands per primer). Twenty one primers exhibiting amplified products gave monomorphic banding patterns. Only one primer (OPE-17) gave a unique extra band of similar size in four plants.

Characterisation of Soybean and Wheat Seeds by Nuclear Magnetic Resonance Spectroscopy

P. Krishnan, D.K. Joshi, M. Maheswari, S. Nagarajan, A.V. Moharir

Biologia plantarum 2004, 48:117-120 | DOI: 10.1023/B:BIOP.0000024286.23683.05

The effects of equilibration under different air relative humidities (RH, 1 - 90 %) and temperatures (35 and 45 °C) on soybean (Glycine max) and wheat (Triticum aestivum) seeds were studied using different techniques. Seed moisture content, electrical conductivity (EC) of seed leachate and per cent seed germination were measured following standard procedures, and compared with nuclear magnetic resonance spin-spin relaxation time (T₂) measurements. Moisture contents of soybean and wheat seeds, following the reverse sigmoidal trend, were greater at 35 than at 45 °C at any particular RH. Changes in T₂ were related to...

Efficient Regeneration of Tetraploid Isatis indigotica Plants via Adventitious Organogenesis from Hypocotyl Explants

L. Zhang, G. Kai, T. Xu, Y. Pi, H. Zhang, X. Sun, K. Tang

Biologia plantarum 2004, 48:121-124 | DOI: 10.1023/B:BIOP.0000024287.23065.e8

An efficient in vitro plant regeneration system via hypocotyl segments of tetraploid Isatis indigotica Fort. was established. Murashige and Skoog's (MS) and Gamborg's (GB₅) media were found to be superior to White medium for promoting shoot regeneration. The highest shoot regeneration (92 %) was achieved from hypocotyls cultured on MS medium containing 8.9 μM benzyladenine (BA) and 2.7 μM naphthaleneacetic acid (NAA), with an average of 4.2 shoots developed per explant. Plant regeneration was also improved when the explants were cultured in MS basal medium containing 3 % (m/v) sucrose and grown under a 12-h photoperiod....

Glutamine: A Suitable Nitrogen Source for Enhanced Shoot Multiplication in Cucumis sativus L.

A. Vasudevan, N. Selvaraj, A. Ganapathi, S. Kasthurirengan, V. Ramesh Anbazhagan, M. Manickavasagam

Biologia plantarum 2004, 48:125-128 | DOI: 10.1023/B:BIOP.0000024288.82679.50

Shoot tip explants of cucumber (Cucumis sativus L. cv. Poinsett 76) were cultured in vitro on Murashige-Skoog medium with L-glutamine, ammonium nitrate, adenine sulphate, asparagine, ammonium succinate, potassium nitrate and sodium nitrate as the nitrogen sources along with optimal concentration of 0.044 mM benzyladenine to study their effects on in vitro morphogenesis. The explants grown with 0.068 mM L-glutamine displayed the highest culture response (74.6 %) and greatest shoot number per explant (13.6) at the end of two subcultures. The explants cultured with other nitrogen sources resulted in low culture frequency and low number...

In vitro Plant Regeneration and Genotype Conservation of Eight Wild Species of Curcuma

R.K. Tyagi, A. Yusuf, P. Dua, A. Agrawal

Biologia plantarum 2004, 48:129-132 | DOI: 10.1023/B:BIOP.0000024289.68669.ef

In vitro protocols for plantlet regeneration and medium-term genotype conservation of eight wild species of Curcuma have been optimized. Both the phenomena were genotype-dependent and influenced significantly by type and concentration of cytokinins used. In general, benzyladenine (BA) was found superior to other cytokinins tested for plantlet regeneration and γ,γ-dimethylallylaminopurine (2iP) for conservation. Number of shoots per culture ranged from 1.3 to 7.2 and conservation period from 264 to 379 d. In 30-d-old cultures, highest frequency of shoot regeneration could be obtained in C. malabarica (7.2 shoots per...

Influence of Acidity on Growth and Biochemistry of Pennisetum clandestinum

M. Sidari, M.R. Panuccio, A. Muscolo

Biologia plantarum 2004, 48:133-136 | DOI: 10.1023/B:BIOP.0000024290.38546.8a

Hydroponics were used to study the impact of acidity on growth, nutritive properties and metabolic changes in kikuyu grass (Pennisetum clandestinum Hochst). Four treatments (pH 6.0, 5.0, 4.0, and 3.0) were compared for effects on biomass, leaf and root length, crude protein, amino acid content and key enzymes of sugar metabolism. Reduction in biomass, root and leaf length, amino acid contents, glucose-6-phosphate dehydrogenase (G6PDH) and pyruvate kinase (PK) content was observed only at pH 3.0, in association with increased leaf proline content. Kikuyu grass is able to grow normally under mild acidity (down to at least pH 4.0).

Effect of Norway Spruce Planting Density on Shoot Morphological Parameters

R. Pokorný, O. Urban, M.V. Marek

Biologia plantarum 2004, 48:137-139 | DOI: 10.1023/B:BIOP.0000024291.70345.b4

Temporal and spatial variations of shoot structural parameters, including shoot silhouette to projected needle area ratio, are very important, e.g., for the correction of leaf area index estimated by indirect methods. Here we bring few examples of their evolution within mountain spruce monoculture planted in two different densities.

Iron Chlorosis in Grafted Sweet Orange (Citrus sinensis L.) Plants: Physiological and Biochemical Responses

V. Chouliaras, I. Therios, A. Molassiotis, G. Diamantidis

Biologia plantarum 2004, 48:141-144 | DOI: 10.1023/B:BIOP.0000024292.51938.aa

Fe deficiency was imposed in Citrus sinensis L. cultivars Valencia and New Hall grafted on C. aurantium and Swingle citrumelo rootstocks by the absence of Fe (-Fe) or by the presence of bicarbonate in the Hoagland nutrient solution. In Fe-deprived leaves total and active Fe concentration, and peroxidase and catalase activities were decreased while the ratios carotenoids/chlorophylls, P/Fe, and K/Ca were increased. Fe(III) chelate reductase activity was induced in (-Fe)-treated roots whereas it was depressed in bicarbonate-treated roots.

Improvement of Biomass Partitioning, Flowering and Yield by Triadimefon in UV-B Stressed Vigna radiata (L.) Wilczek

K. Rajendiran, M.P. Ramanujam

Biologia plantarum 2004, 48:145-148 | DOI: 10.1023/B:BIOP.0000024293.31266.a2

Elevated UV-B radiation (12.2 kJ m^-2 d^-1) as against the ambient level of 10 kJ m^-2 d^-1 affected flowering, productivity and biomass partitioning of green gram [Vigna radiata (L.) Wilczek cv. KM-2]. UV-B stress delayed flowering initiation and achievement of 50 % flowering, reduced flower retention by 25 %, potential yield by 18 % and all yield attributes such as pod number (25 %), pod mass (41 %), seed number (32 %) and seed mass (45 %). Harvest index and shelling percentage were also reduced by 31 and 7 %, respectively. Application of triadimefon (20 mg dm^-3) to unstressed plants accelerated...

Photosynthetic Responses for Vitis vinifera Plants Grown at Different Photon Flux Densities Under Field Conditions

M. Bertamini, N. Nedunchezhian

Biologia plantarum 2004, 48:149-152 | DOI: 10.1023/B:BIOP.0000024294.75496.a6

In grapevine (Vitis vinifera L.) leaf chlorophyll (Chl) a and Chl b and carotenoid contents were higher in plants grown at low photon flux densities (PFD) than in those grown at medium and high PFD. The highest Chl a variable to maximum fluorescence ratio F_v/F_m was observed in plants grown at medium PFD while the minimum fluorescence F₀ was highest in those at high PFD. In isolated thylakoids, both high and low PFD caused marked inhibition of whole chain and photosystem 2 (PS2) activities. The artificial exogenous electron donor diphenyl carbazide significantly restored the loss of PS2 activity...

Cadmium-Induced Changes in Chloroplast Lipids and Photosystem Activities in Barley Plants

A. Vassilev, F. Lidon, P. Scotti, M. Da Graca, I. Yordanov

Biologia plantarum 2004, 48:153-156 | DOI: 10.1023/B:BIOP.0000024295.27419.89

Fatty acid content and composition of chloroplast membranes, ethylene production associated with thylakoid lipids degradation as well as photosynthetic electron transport involving photosystems 1 and 2 were used to determine the effects of increasing Cd concentrations in the growth medium [0, 14, 28, and 42 mg (Cd) kg^-1(sand)] on the photosynthetic performance of barley plants (H. vulgare L., cv. CE9704). High concentrations of Cd triggered serious disturbances of the chloroplast membranes. Ethylene production increased whereas a drop of 18:3 fatty acid content occurred, indicating that Cd mediates lipid peroxidation in the thylakoids....

Growth and Endogenous Cytokinins of Juniper Shoots as Affected by High Metal Concentrations

L.Y. Atanasova, M.G. Pissarska, G.S. Popov, G.I. Georgiev

Biologia plantarum 2004, 48:157-159 | DOI: 10.1023/B:BIOP.0000024296.01389.f2

The growth and the content of endogenous cytokinins (CKs) of current-year-old shoots from juniper plants (Juniperus communis L.) growing over and off ore site were compared. The juniper shoots from ore site (M plants) had higher metal content and exhibited delayed growth. Less bases and nucleosides of Z- and iP- type CK and more iP-conjugates were present in the M shoots. These changes were probably due to inhibited CK export from the roots and/or altered CK metabolism forming less biologically active CKs.