Origin and development of secondary somatic embryos in transformed embryogenic cultures of Medicago sativa

B. Uzelac, S. Ninković, A. Smigocki, S. Budimir

Biologia plantarum 51:1-6, 2007 | DOI: 10.1007/s10535-007-0001-4

Non-transformed and transformed embryogenic cultures of alfalfa (Medicago sativa L. cv. Zaječarska 83), long-term maintained on growth regulator-free medium, were histologically analyzed. In all examined cultures, somatic embryos at various stages of development were observed and secondary embryos were formed in the cotyledonary, hypocotylary and radicular region of the primary embryos. Detailed histological analysis of the torpedo shape somatic embryo revealed that secondary somatic embryos arose directly from single epidermal cells of hypocotylary axis after an unequal periclinal division. Bipolar proembryos were composed of one smaller cytoplasm...

Micropropagation of Juniperus phoenicea from adult plant explants and analysis of ploidy stability using flow cytometry

J. Loureiro, A. Capelo, G. Brito, E. Rodriguez, S. Silva, G. Pinto, C. Santos

Biologia plantarum 51:7-14, 2007 | DOI: 10.1007/s10535-007-0003-2

We report here the successful micropropagation of adult Juniperus phoenicea L. with respective ploidy stability studies. Microcuttings with axillary buds were grown on five media supplemented with different growth regulator combinations. Best elongation rates were achieved on Driver and Kuniyuki (DKW) medium supplemented with kinetin alone or with naphthaleneacetic acid (NAA), while Rugini olive (OM) medium stimulated the development of new branches. Shoots growing on Murashige and Skoog (MS) medium browned and showed necrotic zones. Shoots of second to fourth subcultures usually had higher elongation rates than those of the first culture. For...

Genetic stability, ex vitro rooting and gene expression studies in Hagenia abyssinica

T. Feyissa, M. Welander, L. Negash

Biologia plantarum 51:15-21, 2007 | DOI: 10.1007/s10535-007-0004-1

Randomly amplified polymorphic DNA (RAPD) markers were used to assess genetic stability of 80 micropropagated Hagenia abyssinica plants, 40 of axillary origin and 40 of adventitious origin. The shoots were isolated from the same mother tree and micropropagated for over two years. Among the 83 RAPD primers screened, 16 gave reproducible band patterns. These 16 primers produced 115 bands for each plant. One plant from axillary origin showed two unique bands with primer OPC-11. All other plants showed identical band patterns. Generally, there was no significant difference in the shoot multiplication rate between shoots of axillary and adventitious...

Assessment of genetic fidelity of micropropagated Swertia chirayita plantlets by ISSR marker assay

P. Joshi, V. Dhawan

Biologia plantarum 51:22-26, 2007 | DOI: 10.1007/s10535-007-0005-0

Inter simple sequence repeat (ISSR) marker assay was employed to validate the genetic fidelity of Swertia chirayita plantlets multiplied in vitro by axillary multiplication upto forty-two passages. Sixteen ISSR primers generated a total of 102 amplicons among the tissue-cultured plants. Forty-eight amplicons were amplified in the outlier (a Swertia species). The outlier (negative control) was employed to rule out the possibility that the invariant fingerprint was due to chance alone and that the ISSR technique employed was not discriminatory enough to detect the off-types. A homogenous amplification profile was observed for all...

Development of the CELLOP optimisation model for plant cell cultivation

M. Eeva, P. Vuorela, P. Tammela, M. Nyman, S. Ojala, K. Fagerstedt, H. Haario, H. Vuorela

Biologia plantarum 51:27-33, 2007 | DOI: 10.1007/s10535-007-0006-z

A mathematical computer-aided model CELLOP was constructed in which the desirability functions in a three-dimensional experimental design can be used to find the optimal growing conditions for plant cells. CELLOP is intended for the optimisation of 3 to 6 physical, chemical, or biological variables in the cultivation conditions of plant cell cultures. The model was used to optimise the culturing conditions (calcium, inorganic nitrogen, and sucrose concentrations) for coumarin-producing, spontaneously embryogenic cell lines of angelica Angelica archangelica L. subsp. archangelica and hogs fennel Peucedanum palustre (L.) Moench....

Production of asiaticoside and madecassoside in Centella asiatica in vitro and in vivo

Z. A. Aziz, M. R. Davey, J. B. Power, P. Anthony, R. M. Smith, K. C. Lowe

Biologia plantarum 51:34-42, 2007 | DOI: 10.1007/s10535-007-0008-x

The localization was determined of the triterpenoids, asiaticoside and madecassoside, in different organs of glasshouse-grown plants and cultured material, including transformed roots, of two phenotypes of Centella asiatica (L.) Urban of Malaysian origin. Methanolic extracts of asiaticoside and madecassoside were prepared for gradient HPLC analysis. The two phenotypes of C. asiatica exhibited differences in terpenoid content that were tissue specific and varied between glasshouse-grown plants and tissue culture-derived material. Terpenoid content was highest in leaves, with asiaticoside (0.79 ± 0.03 and 1.15 ± 0.10 % of...

Chromosome analysis and sorting in Vicia sativa using flow cytometry

P. Kovářová, A. Navrátilová, J. Macas, J. Doležel

Biologia plantarum 51:43-48, 2007 | DOI: 10.1007/s10535-007-0009-9

Procedures were developed for flow cytometric analysis and sorting of mitotic chromosomes (flow cytogenetics) of common vetch (Vicia sativa L., 2n=12). Suspensions of intact chromosomes were prepared from root tips after cell cycle synchronization, formaldehyde fixation, and mechanical homogenization. On average, 3 × 10⁵ morphologically intact chromosomes could be isolated from 25 root tips. Flow cytometric analysis of DAPI-stained chromosomes resulted in histograms of relative fluorescence intensity (flow karyotypes) containing four peaks, representing particular chromosomes and/or pairs of chromosomes with similar relative DNA content....

Green fluorescent protein reveals variability in vacuoles of three plant species

G. P. Di Sansebastiano, L. Renna, M. Gigante, M. De Caroli, G. Piro, G. Dalessandro

Biologia plantarum 51:49-55, 2007 | DOI: 10.1007/s10535-007-0010-3

Two vacuolar green fluorescent proteins (GFP) were stably inserted in Nicotiana tabacum and Nicotiana benthamiana genome, with unexpected difficulties, and compared with A. thaliana cv. Wassilewskaja transgenic plants expressing the same constructs. GFP fluorescence was strong in all tissues of A. thaliana but it was barely visible in Nicotiana. Confocal microscopy analysis revealed a variable distribution of the marker in those cells where GFP fluorescence was visible. The role of light dependent proteases was the variable pointing out more inter-species diversity. GFPs degradation was much higher in Nicotiana...

Decreased amount of reducing sugars in transgenic potato tubers and its influence on yield characteristics

O. Navrátil, L. Fischer, J. Čmejlová, M. Linhart, J. Vacek

Biologia plantarum 51:56-60, 2007 | DOI: 10.1007/s10535-007-0011-2

This work focuses on the comparison of field characteristics and amounts of reducing sugars in cold-stored tubers of transgenic plants derived from two potato cultivars. The bacterial gene coding for phosphofructokinase under the tuber-specific promoter was used to support the glycolysis in stored tubers. While the tubers from untransformed control plants steadily accumulated reducing sugars during cold storage, the tubers from transformed plants regardless the genotype were characterized by subsequent decrease in the sugar content. After long period of cold storage the greatest reduction in the reducing sugar content was by more than 60 % compared...

Agrobacterium-mediated high frequency transformation in dwarf recalcitrant rice cultivars

P. Kant, S. Kant, R. K. Jain, V. K. Chaudhury

Biologia plantarum 51:61-68, 2007 | DOI: 10.1007/s10535-007-0012-1

The Agrobacterium-mediated transformation was done in rice (Oryza sativa L. var. indica) cv. HKR126 and elite cross-bred cv. Pusa Basmati1 (PB1), using strain LBA4404 containing pCAMBIA1300 cloned with gene cassettes; potato proteinase inhibitor and Bacillus thuringiensis endotoxin (plasmid JDW53) or mannitol-1-phosphate dehydrogenase (plasmid RKJ108). Co-cultivation with scutellar-calli derived from mature seeds showed stable and highly efficient transformation. In cvs. HKR126 and PB1, 35 % and 41 % of hygromycin resistant calli were obtained. The transformation efficiency in PB1 (22.0 %) was much higher than in HKR126...

Agrobacterium tumefaciens-mediated transformation of blackgram: An assessment of factors influencing the efficiency of uidA gene transfer

R. Saini, P. K. Jaiwal

Biologia plantarum 51:69-74, 2007 | DOI: 10.1007/s10535-007-0014-z

Agrobacterium tumefaciens strain EHA105 carrying a binary vector pCAMBIA2301, which contains a neomycin phosphotransferase gene (nptII) and a β-glucuronidase (GUS) gene (uidA) interrupted with an intron, was used for transformation of Vigna mungo cotyledonary node explants. Various factors such as preculture and wounding of explants, manipulations in inoculation and co-cultivation conditions were found to play a significant role in influencing tissue competence, Agrobacterium virulence and compatibility of both, for achieving the maximum transformation frequencies. The stable transformation with 4.31 % efficiency...

Estimation of endogenous contents of phytohormones during internode development in Merremia emarginata

D. Patel, V. S. Thaker

Biologia plantarum 51:75-79, 2007 | DOI: 10.1007/s10535-007-0015-y

During the entire period of internode growth of Merremia emarginata contents of gibberellic acid (GA₃), phenyl-acetic acid (PAA), indole-3-acetic acid (IAA, free and conjugated) and abscisic acid (ABA, free and conjugated) were estimated by ELISA using polyclonal antibodies raised against each hormones. At the time of internode elongation free auxin content was low and increased with the decrease in the rate of elongation. In contrast, conjugated IAA showed declining trend where free IAA content was remarkably high, suggesting thereby that conjugated IAA might have mobilized during the later phase of internode development. The endogenous...

Kinetin regulates plant growth and biochemical changes during maturation and senescence of leaves, flowers, and pods of Cajanus cajan L.

D. Mukherjee, R. Kumar

Biologia plantarum 51:80-85, 2007 | DOI: 10.1007/s10535-007-0016-x

Aspects of plant growth such as height, branch number, leaf number, leaf area, pod area, 100-seed mass, etc., were correlated with biochemical changes such as contents of chlorophyll (Chl), proteins, DNA, and RNA, and protease activity during development and senescent phases in leaves, flowers, and pods of Cajanus cajan L. cv. UPAS-120 after treatments with kinetin (Kn). A significant increase was noticed in branch number, leaf number, leaf area, and seed mass while other growth processes registered a small increase after Kn application. Effectiveness of 5 µM Kn was also noticed in minimizing the loss of Chls, proteins, and nucleic...

Superoxide dismutase activity in C₃ and C₃/CAM intermediate species of Clusia

Z. Miszalski, A. Kornas, K. Gawronska, I. Ślesak, E. Niewiadomska, J. Kruk, A. L. Christian, E. Fischer-Schliebs, R. Krisch, U. Lüttge

Biologia plantarum 51:86-92, 2007 | DOI: 10.1007/s10535-007-0018-8

The C₃-CAM intermediate Clusia minor L. and the C₃ obligate Clusia multiflora H.B.K. plants were exposed for 7 d to a combination of drought stress and high irradiance of about 1200 µmol m^-2 s^-1 for 12 h per day. In both species under these conditions a strong decrease in stomatal conductance was observed at dawn and dusk. Changes in stomatal behaviour of C. minor were accompanied by only a low nocturnal accumulation of malate and citrate. Thus, in C. minor drought stress applied in combination with high irradiance limited CAM expression, and possibly this is the main reason...

Effect of seed soaking with thiols on the antioxidant enzymes and photosystem activities in wheat subjected to water stress

N. S. Nathawat, J. S. Nair, S. M. Kumawat, N. S. Yadava, G. Singh, N. K. Ramaswamy, M. P. Sahu, S. F. D'Souza

Biologia plantarum 51:93-97, 2007 | DOI: 10.1007/s10535-007-0019-7

Photosystem 1 and 2 and antioxidant enzyme activities were determined in wheat (Triticum aestivum L. cv. Sonalika) leaves. Seedlings from both control seeds and seeds soaked in solutions like dithiothreitol, thioglycollic acid and thiourea were subjected to water stress induced by polyethylene glycol. Photosystem 1 and 2 activities were less inhibited by water stress due to seed soaking with sulphydryl compounds. The changes in activities of antioxidant enzymes induced by water stress were higher in seedlings from thiol-pretreated seeds than from water-soaked seeds.

Effect of drought on biomass, protein content, lipid peroxidation and antioxidant enzymes in two sesame cultivars

F. Fazeli, M. Ghorbanli, V. Niknam

Biologia plantarum 51:98-103, 2007 | DOI: 10.1007/s10535-007-0020-1

The effects of drought on growth, protein content, lipid peroxidation, superoxide dismutase (SOD), peroxidase (POX), catalase (CAT) and polyphenol oxidase (PPO) were studied in leaves and roots of Sesamum indicum L. cvs. Darab 14 and Yekta. Four weeks after sowing, plants were grown under soil moisture corresponding to 100, 75, 50 and 25 % field capacity for next four weeks. Fresh and dry masses, and total protein content in leaves and roots decreased obviously under drought. However, several new proteins appeared and content of some proteins was affected. Measurement of malondialdehyde content in leaves and roots showed that lipid peroxidation...

Expression of dehydrins under heat stress and their relationship with water relations of sugarcane leaves

A. Wahid, T. J. Close

Biologia plantarum 51:104-109, 2007 | DOI: 10.1007/s10535-007-0021-0

The heat stress-induced dehydrin proteins (DHNs) expression and their relationship with the water relations of sugarcane (Saccharum officinarum L.) leaves were studied. Sugarcane seedlings were subjected to heat stress (day/night temperature of 40/35 °C) under relative humidity 60/65 % to avoid aerial desiccation and determinations made at 4, 12, 24, 36, 48, 60 and 72 h. The leaves showed a sharp decline in the water and osmotic potentials, and relative water content during first 12 h of heat stress, but a regain in their values in 24 h. The pressure potential (ψ_p) decreased initially but increased later and approached control...

Salinity induced changes in proline and betaine contents and synthesis in two aquatic macrophytes differing in salt tolerance

S. B. Tripathi, K. Gurumurthi, A. K. Panigrahi, B. P. Shaw

Biologia plantarum 51:110-115, 2007 | DOI: 10.1007/s10535-007-0022-z

The present work investigated the effect of NaCl and seawater salinity (SWS) on accumulation of proline and glycinebetaine (betaine) and expression of two key enzymes of their biosynthetic pathway, betainealdehyde dehydrogenase (BADH) and Δ¹-pyrroline-5-carboxylate synthetase (P5CS) in two aquatic macrophytes, salt-tolerant Najas gramenia and moderately-salt-tolerant Najas indica. N. gramenia did not show any accumulation of betaine or expression of BADH in response to NaCl or SWS treatments. The content of proline increased significantly in response to the salt treatments. High expression of P5CS was also observed, however,...

Accumulation and detoxification of cadmium in Brassica pekinensis and B. chinensis

C. P. Liu, Z. G. Shen, X. D. Li

Biologia plantarum 51:116-120, 2007 | DOI: 10.1007/s10535-007-0023-y

The effect of excessive Cd on the growth and metal uptake by leafy vegetables Brassica chinensis L. (cv. Wuyueman) and Brassica pekinensis (Lour.) Rupr. (cv. Qingyan 87-114) were studied in hydroponic solution culture. The Cd concentration higher than 10 µM significantly decreased the root elongation and leaf chlorophyll contents of both plant species. The shoots of B. pekinensis had significantly higher concentrations of total and water-soluble Cd than B. chinensis. The roots of both species accumulated more Cd than the shoots in all the Cd treatments. Most of the Cd in the roots was found in the cell walls. The shoot/root...

Lead-induced oxidative stress and metabolic alterations in Cassia angustifolia Vahl.

M. I. Qureshi, M. Z. Abdin, S. Qadir, M. Iqbal

Biologia plantarum 51:121-128, 2007 | DOI: 10.1007/s10535-007-0024-x

Forty-five-days old plants of Indian senna (Cassia angustifolia Vahl.) were subjected to 0-500 µM lead acetate (Pb-Ac) in pot culture. Changes in contents of thiobarbituric acid reactive substances (TBARS), ascorbate, glutathione, proline, sennosides (a+b), and activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR), and catalase (CAT) were studied at pre-flowering (60 d after sawing, DAS), flowering (90 DAS) and post-flowering (120 DAS) stages of plant development. Compared with the controls, the Pb-Ac treated plants showed an increase in contents of TBARS, dehydroascorbate, oxidized...

Mapping of QTLs affecting copper tolerance and the Cu, Fe, Mn and Zn contents in the shoots of wheat seedlings

A. F. Bálint, M. S. Röder, R. Hell, G. Galiba, A. Börner

Biologia plantarum 51:129-134, 2007 | DOI: 10.1007/s10535-007-0025-9

Quantitative trait loci (QTLs) for Cu-tolerance were determined in wheat grown in control and Cu-treated soil in greenhouse. In addition, loci having an influence on the shoot Cu-, Fe-, Mn-and Zn-contents under non-stressed and Cu-stressed environments were mapped. One major QTL for Cu-tolerance was found on chromosome 5DL, while slighter effects were determined on the chromosomes 1AL, 2DS, 4AL, 5BL and 7DS. QTLs affecting the shoot Mn-and Zn-contents were found on the chromosomes 3BL and 3AL, respectively. The centromeric region on the chromosome 3B plays a role in the regulation of the shoot Fe-contents in the stressed plants. Under Cu-stress QTL...

Thaumatin gene confers resistance to fungal pathogens as well as tolerance to abiotic stresses in transgenic tobacco plants

M. V. Rajam, N. Chandola, P. Saiprasad Goud, D. Singh, V. Kashyap, M. L. Choudhary, D. Sihachakr

Biologia plantarum 51:135-141, 2007 | DOI: 10.1007/s10535-007-0026-8

We report here the development of transgenic tobacco plants with thaumatin gene of Thaumatococcus daniellii under the control of a strong constitutive promoter-CaMV 35S. Both polymerase chain reaction and genomic Southern analysis confirmed the integration of transgene. Transgenic plants exhibited enhanced resistance with delayed disease symptoms against fungal diseases caused by Pythium aphanidermatum and Rhizoctonia solani. The leaf extract from transgenic plants effectively inhibited the mycelial growth of these pathogenic fungi in vitro. The transgenic seeds exhibited higher germination percentage and seedling survival...

Agrobacterium-mediated transformation of indica rice with chitinase gene for enhanced sheath blight resistance

R. Nandakumar, S. Babu, K. Kalpana, T. Raguchander, P. Balasubramanian, R. Samiyappan

Biologia plantarum 51:142-148, 2007 | DOI: 10.1007/s10535-007-0027-7

Four rice indica genotypes of local importance were transformed with RC7, rice chitinase cDNA clone through Agrobacterium-mediated gene transfer method using mature seed derived calli as explants. The putative hygromycin resistant calli showed varied level of regeneration efficiency ranging from 2.0 to 7.6 %. The stable integration and expression of RC7 was confirmed through polymerase chain reaction (PCR) and Western analysis. Transformation efficiency ranged from 0.9 to 5.2 %. The expression of RC7 (35 kDa chitinase) in different tissues of transgenic plant (root, sheath and leaf) was proved through Western analysis and...

Chitinase and peroxidase activities in sunflower hypocotyls: Effects of BTH and inoculation with Plasmopara halstedii

A. Roldán Serrano, J. Luna del Castillo, J. Jorrín Novo, A. Fernández Ocaña, M. V. Gómez Rodríguez

Biologia plantarum 51:149-152, 2007 | DOI: 10.1007/s10535-007-0028-6

Systemic acquired resistance (SAR) can be induced in plants by incompatible pathogens, pathogen derived extracts, or certain chemicals as benzothiadiazole (BTH). The aim of this work was to compare changes in peroxidase and chitinase activities, enzymes considered as PR-proteins, caused by BTH and the pathogen Plasmopara halstedii. Hypocotyls from susceptible and resistant BTH-treated sunflower seedlings showed increased peroxidase and chitinase activities. Inoculation with P. halstedii increased chitinase and peroxidase activities in inoculated hypocotyls from susceptible but not from resistant sunflower seedlings.

Geophytoelectrical current in trees of a subtropical rainforest in Mexico

L. Yáñez-Espinosa, T. Terrazas, L. López-Mata, L. Fucikovsky

Biologia plantarum 51:153-156, 2007 | DOI: 10.1007/s10535-007-0029-5

The geophytoelectrical current of three evergreen tropical tree species is studied as an indirect measure of their relative water content. Two intermediate shade-tolerant species (Aphananthe monoica and Pleuranthodendron lindenii), distributed in the middle and upper canopy strata, and an understory shade-tolerant species (Psychotria costivenia) were examined. The annual rhythm of geophytoelectrical currents per cm of diameter (DBH) is seasonal, with the highest occurrence in the winter and summer. There is a significant association between maximum temperature, moisture in the environment, and geophytoelectrical current per cm...

Increased antioxidant activity in Cassia seedlings under UV-B radiation

S. Agarwal

Biologia plantarum 51:157-160, 2007 | DOI: 10.1007/s10535-007-0030-z

Cassia auriculata L. seedlings were irradiated with ultraviolet B (UV-B) in an environment-control chamber. The two doses assayed (7.5 and 15.0 kJ m^-2) induced oxidative damage with an increase in lipid peroxidation and hydrogen peroxide and a decrease in chlorophyll and total phenol contents. The ascorbate and dehydroascorbate content as well as the reduced glutathione/oxidized glutathione content and ratio were significantly increased. The UV-B stress led to significant increases of the activity of superoxide dismutase, catalase, peroxidase and polyphenol oxidase. It is suggested that Cassia seedlings try to counteract high...

Withanolide production by in vitro cultures of Withania somnifera and its association with differentiation

M. Sharada, A. Ahuja, K. A. Suri, S. P. Vij, R. K. Khajuria, V. Verma, A. Kumar

Biologia plantarum 51:161-164, 2007 | DOI: 10.1007/s10535-007-0031-y

Withanolides-steroidal lactones, isolated from various Solanaceous plants have received considerable attention due to their potential biological activities. Five selected withanolides (withanone, withaferin A, withanolide A, withanolide B, withanolide E) were identified by HPLC-UV (DAD) - positive ion electrospray ionization mass spectroscopy in Withania somnifera (L.) Dunal cv. WSR plants and tissues cultured in vitro at different developmental phases. Cultures were established from five explants on Murashige and Skoog's medium supplemented with different plant growth regulators. Results suggest that production of withanolides...

Photosynthetic rate and yield formation in different maize hybrids

L. Ding, K. J. Wang, G. M. Jiang, M. Z. Liu, L. M. Gao

Biologia plantarum 51:165-168, 2007 | DOI: 10.1007/s10535-007-0032-x

The relationship between photosynthetic rate and yield formation processes of the newer and older maize hybrids were investigated. Leaf area at flowering (source) and kernel number (sink) of the newer hybrids were greater than the older ones although their light-saturated photosynthetic rate (P_sat) were not greater than the older ones before flowering. After flowering, P_sat and chlorophyll content of the newer hybrids declined more slowly than the older ones. They not only distributed almost all photosynthates produced after flowering to grain but also reallocated some reserved photosynthates produced before flowering to grain....

Molecular characterization of Mauritanian date palm cultivars using plasmid-like DNAs markers

A. Ould Mohamed Salem, S. Rhouma, S. Zehdi, M. Marrakchi, M. Trifi

Biologia plantarum 51:169-172, 2007 | DOI: 10.1007/s10535-007-0033-9

Mauritanian date palm cultivars and progenies of two controlled crosses were analyzed according to the identity of mitochondrial plasmid-like DNAs. Starting from total genomic DNA and appropriate primers, polymerase chain reaction was designed to amplify either a 373-bp or a 265-bp fragments corresponding to the S and the R-plasmid respectively. Data proved that 5 cultivars out of 10 studied have exhibited the R-plasmid suggesting their resistance to the fusariosis. The existence of intra-cultivar variability has also been revealed in the cv. Ahmar. In addition, analysis throughout progenies of two controlled crosses suggested the strict maternal transmission...

Agar/galactomannan gels applied to shoot regeneration from tobacco leaves

N. Lucyszyn, M. Quoirin, M. M. Homma, M.-R. Sierakowski

Biologia plantarum 51:173-176, 2007 | DOI: 10.1007/s10535-007-0034-8

This study concerns the efficacy of partial agar substitution by galactomannans as support in plant regeneration media for Nicotiana tabacum. The production of multiple shoots from leaf-derived callus and their rooting were evaluated. The galactomannans applied were obtained from Cassia fastuosa (cassia) and Cyamopsis tetragonolobus (guar gum - a commercial galactomannan) seeds. The results obtained on media solidified with mixtures of agar/galactomannan (3 g dm^-3 each) gels were compared with those on media gelled with a standard concentration of agar (6 g dm^-3). The in vitro performance allowed to...

Effect of NaCl and CaCl₂ on growth and contents of minerals, chlorophyll, proline and sugars in the apple rootstock M 4 cultured in vitro

T. E. Sotiropoulos

Biologia plantarum 51:177-180, 2007 | DOI: 10.1007/s10535-007-0035-7

The apple (Malus domestica Borkh) rootstock M 4 shoots were grown in vitro for 4 weeks on Murashige and Skoog (MS) medium containing three NaCl concentrations (35, 100 and 200 mM) in combination with two CaCl₂ concentrations (5 and 10 mM). Inclusion of 10 mM CaCl₂ in the medium, in the presence of 35 mM NaCl, significantly increased the number of shoots and the fresh mass compared to 5 mM CaCl₂. The number of shoots, length of shoots, and the fresh mass of cultures were very low in the presence of 100 and 200 mM NaCl, independently of CaCl₂ concentration of the medium. By increasing NaCl and...

Growth, abscisic acid content, and carbon isotope composition in wheat cultivars grown under different soil moisture

T. Wang, X. Zhang, C. Li

Biologia plantarum 51:181-184, 2007 | DOI: 10.1007/s10535-007-0036-6

Changes in dry matter accumulation and allocation, abscisic acid content and carbon isotope composition of three wheat cultivars from dry, middle and wet climate regions were recorded at full maturity after exposure to different watering regimes (100, 50 and 25 % field capacity). Compared with the wet climate cultivar, the dry climate cultivar showed lower stem height, total leaf area, total dry biomass and total grain dry mass, and higher root/shoot ratio, abscisic acid content and carbon isotope composition under all watering regimes. Both water-limited treatments significantly reduced leaf growth and increased dry matter allocation into the roots...

Multigenerational inbreeding in Succisa pratensis: Effects on fitness components

F. X. Picó, C. Mix, N. J. Ouborg, J. M. Van Groenendael

Biologia plantarum 51:185-188, 2007 | DOI: 10.1007/s10535-007-0037-5

We examined the effects of repeated inbreeding on fitness components of the long-lived perennial Succisa pratensis (Dipsacaceae). Plants from six populations differing in size were used to establish lines with expected inbreeding coefficients f of 0, 0.5 and 0.75. The effects of different inbreeding levels were measured for seed set, seed mass, percentage germination and seedling relative growth rate. Seed set decreased following one generation of inbreeding and seedling growth rate decreased after two generations of inbreeding. Our study indicated that the mutational load is difficult to purge and that continued inbreeding tends...

Influence of UV-B radiation on young triticale plants with different wax cover

E. Skórska, W. Szwarc

Biologia plantarum 51:189-192, 2007 | DOI: 10.1007/s10535-007-0038-4

Ultraviolet-B radiation (biologically effective dose 2.6 kJ m^-2 d^-1) had negative influence on morphology and physiology of the young triticale plants. Plants exposed to UV-B were of lower height than control plants, their leaves were narrow, and the rate of net photosynthesis was decreased. The line RAH 336, which wax cover is lesser than that of traditional cultivar Magnat, was more susceptible to UV-B radiation, considering primary photosynthesis reactions, recorded by chlorophyll a fluorescence. An activation of protective mechanisms was observed: plants responded to UV-B by an increase of the content of UV-B absorbing...

Developmental stage as a possible factor affecting cytokinin content and cytokinin dehydrogenase activity in Pinus sylvestris

A. E. Valdés, P. Galuszka, B. Fernández, M. L. Centeno, I. Frébort

Biologia plantarum 51:193-197, 2007 | DOI: 10.1007/s10535-007-0039-3

In the present study cytokinin dehydrogenase (CKX) activity was for the first time found in a conifer species, Pinus sylvestris. The activities were correlated with the endogenous cytokinin contents. Several enzyme substrates and two different electron acceptors were used to search for the enzyme activity in the extract from seeds, seedlings and plantlets. The highest specific activity was found in one-year-old plantlets with isopentenyladenine as the substrate and 2,6-dichlorophenolindophenol as the electron acceptor, at pH 8. An enhancement in the CKX specific activity corresponded to increasing contents of cytokinins, mainly isopentenyladenine...

Effects of sugars and growth regulators on in vitro growth of Dactylorhiza species

K. Wotavová-Novotná, H. Vejsadová, P. Kindlmann

Biologia plantarum 51:198-200, 2007 | DOI: 10.1007/s10535-007-0040-x

The influence of sugars and growth regulators on shoot and root growth of Dactylorhiza species was studied under in vitro conditions. The seedling development was stimulated with the application of glucose and sucrose at concentration of 10 g dm^-3 each. The improvement of shoot growth rate and shoot length was enhanced by cytokinins N ⁶-(2-isopentenyl)adenine or N ⁶-benzyladenine and their combination with auxin indolebutyric acid (IBA). The root growth rate and root length of seedlings increased in the presence of IBA and α-naphthaleneacetic acid. Individual Dactylorhiza species...

Fageria, N.K., Baligar, V.C., Clark, R.B.: Physiology of crop production

J. Čatský

Biologia plantarum 51:6, 2007 | DOI: 10.1007/s10535-007-0002-3

Singh, R.J., Jahuar, P.P. (ed.): Genetic Resources, Chromosome Engineering, and Crop Improvement. Cereals. Vol. 2

E. Sýkorová

Biologia plantarum 51:33, 2007 | DOI: 10.1007/s10535-007-0007-y

Huang, B. (ed.): Plant-Environment Interactions. 3^rd Edition

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Biologia plantarum 51:68, 2007 | DOI: 10.1007/s10535-007-0013-0

Montagnini, F. (ed.): Environmental Services of Agroforestry Systems

L. Nátr

Biologia plantarum 51:85, 2007 | DOI: 10.1007/s10535-007-0017-9

Contribution of physiological and morphological adjustments to drought resistance in two Mediterranean tree species

L. Serrano, J. Peñuelas

Biologia plantarum 51:192, 2007 | DOI: 10.1007/s10535-007-0087-8