Cyclic somatic embryogenesis and efficient plant regeneration from callus of safflower

J. Vijaya Kumar, B. D. Ranjitha Kumari, E. Castaño

Biologia plantarum 52:429-436, 2008 | DOI: 10.1007/s10535-008-0087-3

Efficient plant regeneration through somatic embryogenesis was established for safflower (Carthamus tinctorius L.) cv. NARI-6. Embryogenic calli were induced from 10 to 17-d-old cotyledon and leaf explants from in vitro seedlings. High frequency (94.3 %) embryogenic callus was obtained from cotyledon explants cultured on Murashige and Skoog's germination (MSG) basal medium supplemented with thidiazuron, 2-isopentenyladenine and indole-3-butyric acid. Primary, secondary and cyclic somatic embryos were formed from embryogenic calli in a different media free of plant growth regulators, however, 100 % cyclic somatic embryogenesis was obtained...

Improved in vitro rooting of Prunus dulcis Mill. cultivars

S. Tereso, C. M. Miguel, M. Mascarenhas, A. Roque, H. Trindade, J. Maroco, M. M. Oliveira

Biologia plantarum 52:437-444, 2008 | DOI: 10.1007/s10535-008-0088-2

A highly reproducible system was developed for efficient rooting of cultivars Boa Casta (BC) and Peneda and a BC seedling-derived clone (BC VII) of almond (Prunus dulcis Mill.). Twenty-four accessions derived from the clone BC VII and subjected to various in vitro culture treatments were screened. The long induction pre-treatment (LIP, 5 d), the brief induction pre-treatment (BIP, 16 h) and the hormonal shock by short dipping in hormone solution (1 min), were tested. BIP was the only that allowed rooting of cultivars. In BC VII, it induced high rooting frequencies (47-100 %) when using a solution of 0.4 mM indole-3-butyric acid solidified...

Localization of BAC clones on mitotic chromosomes of Musa acuminata using fluorescence in situ hybridization

E. Hřibová, M. Doleželová, J. Doležel

Biologia plantarum 52:445-452, 2008 | DOI: 10.1007/s10535-008-0089-1

A bacterial artificial chromosome (BAC) library of banana (Musa acuminata) was used to select BAC clones that carry low amounts of repetitive DNA sequences and could be suitable as probes for fluorescence in situ hybridization (FISH) on mitotic metaphase chromosomes. Out of eighty randomly selected BAC clones, only one clone gave a single-locus signal on chromosomes of M. acuminata cv. Calcutta 4. The clone localized on a chromosome pair that carries a cluster of 5S rRNA genes. The remaining BAC clones gave dispersed FISH signals throughout the genome and/or failed to produce any signal. In order to avoid the excessive hybridization...

Use of phosphomannose isomerase-based selection system for Agrobacterium-mediated transformation of tomato and potato

J. Bříza, D. Pavingerová, P. Přikrylová, J. Gazdová, J. Vlasák, H. Niedermeierová

Biologia plantarum 52:453-461, 2008 | DOI: 10.1007/s10535-008-0090-8

Two selection systems for Agrobacterium tumefaciens mediated transformation of tomato and potato were compared. In the tomato (Lycopersicon esculentum cv. Moneymaker), the highest transformation rate, 4.2 %, of cotyledon explants on mannose-selection medium was obtained when mannose/sucrose concentration in the regeneration medium was 5/15 g dm^-3. The best transformation efficacy with the commonly used concentration of 100 mg dm^-3 kanamycin as a selection agent was 9 %. In the potato (Solanum tuberosum cv. Bintje), the highest transformation frequency was 53.3 % when mannose concentration in the regeneration...

Cloning of differential expression fragments in cauliflower after Xanthomonas campestris inoculation

Y. Gu, Y. W. Mao, C. G. Wang, Q. C. Zhao, D. L. Sun, W. Q. Song

Biologia plantarum 52:462-468, 2008 | DOI: 10.1007/s10535-008-0091-7

A near isogenic line (NIL) of Brassica oleracea var. botrytis with resistant and susceptible lines C712 and C731, was used in this study. More than 100 differentially expressed cDNA fragments were obtained from black rot resistant cauliflower plants obtained using cDNA-amplified fragment length polymorphism (AFLP) after infection with the pathogen. Thirteen of these fragments were cloned and subjected to reverse Northern blot analysis using both infected and control cDNA pools. Two positive clones, M2 and M6, were isolated. Northern dot blot and Northern blot analyses showed that M2 was constitutively expressed, whereas M6 contained a...

Genetic analysis of fertility-restorer genes in rice

Y. P. Tan, S. Q. Li, L. Wang, G. Liu, J. Hu, Y. G. Zhu

Biologia plantarum 52:469-474, 2008 | DOI: 10.1007/s10535-008-0092-6

Wild-abortive (WA), Honglian (HL) and Baro-II (BT) are three important cytoplasmic male sterility (CMS) types in rice. It is essential to investigate genetic mode and allelism of fertility restorer (Rf) genes and the relationship between Rf and CMS. Fertility of the all test-cross F₁ plants shows that the restorer-maintainer relationship is similar for HL-CMS and BT-CMS, while that is variance for WA-CMS and HL-CMS (or BT-CMS), respectively. Genetic analysis of Rf genes indicates that HL-or BT-CMS are controlled by single dominant Rf gene and WA-CMS is controlled by one or two pairs of dominant Rf genes,...

Gene expression profiling in maize roots under aluminum stress

G. M. A. Cançado, F. T. S. Nogueira, S. R. Camargo, R. D. Drummond, R. A. Jorge, M. Menossi

Biologia plantarum 52:475-485, 2008 | DOI: 10.1007/s10535-008-0093-5

To investigate the molecular mechanisms of Al toxicity, cross-species cDNA array approach was employed to identify expressed sequence tags (ESTs) regulated by Al stress in root tips of Al-tolerant maize (Zea mays) genotype Cat100-6 and Al-sensitive genotype S1587-17. Due to the high degree of conservation observed between sugarcane and maize, we have analyzed the expression profiling of maize genes using 2 304 sugarcane (ESTs) obtained from different libraries. We have identified 85 ESTs in Al stressed maize root tips with significantly altered expression. Among the up-regulated ESTs, we have found genes encoding previously identified proteins...

Suppression subtractive hybridization identifies differentially expressed genes in Brassica napus chlorophyll-reduced mutant

H. Y. Wang, Y. H. Hu, Y. Liu, Y. T. Zhou, M. L. Wang, Y. Zhao

Biologia plantarum 52:486-492, 2008 | DOI: 10.1007/s10535-008-0094-4

Suppressive subtraction hybridization (SSH) was used to identify differentially expressed genes caused by a chlorophyll-reduced mutation in B. napus. The cDNA fragments, derived from SSH positive subtractive library (tester: normal wild type, driver: mutant) were cloned into pMD18-T vector. Two hundred SSH cDNA clones were screened by dot blot array, and 151 clones were identified as differentially expressed cDNA fragments in Cr3529 line. Thirty-six positive clones which showed marked expression differences were selected and sequenced. After redundant cDNAs were removed, 33 differentially expressed unique cDNA section clones were obtained. Among...

Putative primary involvement of Arabidopsis phosphoinositide-specific phospholipase C1 within abscisic acid-induced stomatal closing

A. Cousson

Biologia plantarum 52:493-501, 2008 | DOI: 10.1007/s10535-008-0096-2

Stomatal closing to abscisic acid (ABA) was studied in leaf epidermal peels of a dexamethasone (Dex)-inducible transgenic line expressing the phospholipase C AtPLC1 antisense in the Columbia genetic background. In the absence of Dex, the Ca²⁺ buffer, ethylene glycol-bis(b-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) and the phopholipase C inhibitor, 1-[6-{[17β-3-methoxyestra-1,3,5(10)-trien-17-yl]amino}hexyl]-1H-pyrrole-2,5-dione (U73122) specifically inhibited the response to 20 µM ABA, whereas the Ca²⁺ buffer, 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid...

Changes of pH of solutions during perfusion through stem segments: further evidence for hydrogel regulation of xylem hydraulic properties?

A. Gascó, E. Gortan, S. Salleo, A. Nardini

Biologia plantarum 52:502-506, 2008 | DOI: 10.1007/s10535-008-0097-1

Changes in hydraulic conductivity (K_h) and pH were measured in stem segments of laurel (Laurus nobilis L.) during perfusion with iso-osmotic solutions of KCl, NaCl and sucrose. Sucrose had no effect on K_h while 100 mM NaCl or KCl induced up to 22 and 35 % increase of K_h with respect to deionized water, respectively. Increases in K_h were accompanied by a sharp drop in pH from 6.0 (inlet solution) to 5.0 (outlet solution). The same effect was observed with both KCl and NaCl solutions but not in the case of sucrose. Also, similar changes of K_h and pH were observed for stems killed after immersion...

Nucleolar vacuolation in soybean root meristematic cells during recovery after chilling

D. Stępiński

Biologia plantarum 52:507-512, 2008 | DOI: 10.1007/s10535-008-0098-0

The nucleolar vacuole formation in soybean root meristematic cells from seedlings grown 3 d at temperature 25 °C (control), 3 d at temperature 25 °C and then transferred to 10 °C (chilling) for 4 d, and after recovery for 1.5, 3, 6, 12 and 24 h at 25 °C were observed on semi-thin sections. Simultaneously, autoradiographic studies with ³H-uridine on squashed preparations were carried out. During recovery of plants, the number of vacuolated nucleoli increased gradually from 24 % after 1.5 h up to 40 % after 24 h, while in the control there were 18 % of nucleoli with vacuoles and after 4-d chilling only 5 %. Labelling of cells during 20-min...

Physiology and biochemistry of waterlogging tolerance in plants

R. K. Sairam, D. Kumutha, K. Ezhilmathi, P. S. Deshmukh, G. C. Srivastava

Biologia plantarum 52:401-412, 2008 | DOI: 10.1007/s10535-008-0084-6

Waterlogging is a serious problem, which affects crop growth and yield in low lying rainfed areas. The main cause of damage under waterlogging is oxygen deprivation, which affect nutrient and water uptake, so the plants show wilting even when surrounded by excess of water. Lack of oxygen shift the energy metabolism from aerobic mode to anaerobic mode. Plants adapted to waterlogged conditions, have mechanisms to cope with this stress such as aerenchyma formation, increased availability of soluble sugars, greater activity of glycolytic pathway and fermentation enzymes and involvement of antioxidant defence mechanism to cope with the post hypoxia/anoxia...

Production of reactive oxygen species and development of antioxidative systems during in vitro growth and ex vitro transfer

P. Baťková, J. Pospíšilová, H. Synková

Biologia plantarum 52:413-422, 2008 | DOI: 10.1007/s10535-008-0085-5

Ex vitro transfer is often stressful for in vitro grown plantlets. Water stress and photoinhibition, often accompanying the acclimatization of in vitro grown plantlets to ex vitro conditions, are probably the main factors promoting production of reactive oxygen species (ROS) and in consequence oxidative stress. The extent of the damaging effects of ROS depends on the effectiveness of the antioxidative systems which include low molecular mass antioxidants (ascorbate, glutathione, tocopherols, carotenoids, phenols) and antioxidative enzymes (superoxide dismutase, ascorbate peroxidase, catalase, glutathione reductase, monodehydroascorbate...

Production of recombinant human lactoferrin from transgenic plants

G. Stefanova, M. Vlahova, A. Atanassov

Biologia plantarum 52:423-428, 2008 | DOI: 10.1007/s10535-008-0086-4

Molecular farming provides a powerful tool for low cost production of recombinant proteins with pharmaceutical value. The use of transgenic plants has been increasingly tested as alternative system for obtaining biologically active human lactoferrin in plants. Precise selection of plant species, transformation techniques and expression cassettes, in addition to conduction of detailed glycosylation and immunogenicity studies, serves as basis of obtaining safe recombinant human lactoferrin in high concentrations for the use of pharmacy. On the other hand, expression of antimicrobial protein lactoferrin in plants is a promising opportunity for crop quality...

Kays, S.J., Nottingham, S.F.: Biology and Chemistry of Jerusalem Artichoke Helianthus tuberosus L.

J. Lachman

Biologia plantarum 52:492, 2008 | DOI: 10.1007/s10535-008-0095-3

Palaniswamy, U.R.: Asian Crops and Human Dietetics

J. Pospíšilová

Biologia plantarum 52:552, 2008 | DOI: 10.1007/s10535-008-0108-2

Stability of β-glucuronidase gene expression in transgenic Tricyrtis hirta plants after two years of cultivation

S. Mori, E. Oka, H. Umehara, H. Kobayashi, Y. Hoshi, M. Kondo, K. Ogata, M. Nakano

Biologia plantarum 52:513-516, 2008 | DOI: 10.1007/s10535-008-0099-z

Transgenic plants of Tricyrtis hirta carrying the intron-containing β-glucuronidase (GUS) gene under the control of the CaMV35S promoter have been cultivated for two years. Four independent transgenic plants produced flowers 1-2 years after acclimatization, and all of them contained one copy of the transgene as indicated by inverse polymerase chain reaction (PCR) analysis. All the four transgenic plants showed stable expression of the gus gene in leaves, stems, roots, tepals, stamens and pistils as indicated by histochemical and fluorometric GUS assays, although differences in the GUS activity were observed among different organs...

In vitro propagation of Capsicum chinense Jacq.

K. Sanatombi, G. J. Sharma

Biologia plantarum 52:517-520, 2008 | DOI: 10.1007/s10535-008-0100-x

An efficient micropropagation protocol was established for Capsicum chinense Jacq. cv. Umorok, a pungent chilli cultivar. Shoot-tip explants were cultured on Murashige and Skoog (MS) medium containing cytokinins (22.2-88.8 µM 6-benzylaminopurine, BAP, 23.2-93.0 µM kinetin, Kin, or 22.8-91.2 µM zeatin, Z) alone or in combination with 5.7 µM indole-3-acetic acid (IAA). Maximum number of shoots were induced on medium containing 91.2 µM Z or 31.1 µM BAP with 4.7 µM Kin. The separated shoots rooted and elongated on medium containing 2.5 or 4.9 µM indole-3-butyric acid (IBA). Axillary shoots were induced...

In vitro clonal propagation of Nyctanthes arbor-tristis

G. R. Rout, A. Mahato, S. K. Senapati

Biologia plantarum 52:521-524, 2008 | DOI: 10.1007/s10535-008-0101-9

Rapid shoot multiplication of Nyctanthes arbor-tristis L. was achieved from axillary meristems on Murashige and Skoog (MS) basal medium supplemented with 1.0-1.5 mg dm^-3 6-benzylaminopurine (BA), 50 mg dm^-3 adenine sulfate (Ads) and 3 % (m/v) sucrose. Inclusion of indole-3-acetic acid (IAA) in the culture medium along with BA + Ads promoted a higher rate of shoot multiplication. Maximum mean number of microshoots per explant (6.65) was achieved on the MS medium supplemented with 1.5 mg dm^-3 BA, 50 mg dm^-3 Ads and 0.1 mg dm^-3 IAA after 4 weeks of culture. The elongated shoots rooted within...

Development of a sequence characterized amplified region (SCAR) marker associated with high rooting ability in Larix

H. Li, S. G. Zhang, J. M. Gao, C. G. Wang, Y. Zhang, L. W. Qi, L. Chen, W. Q. Song

Biologia plantarum 52:525-528, 2008 | DOI: 10.1007/s10535-008-0102-8

In this study, bulked segregant analysis (BSA) was used on Larix leptolepis × Larix olgensis hybrids to identify a random amplified polymorphic DNA (RAPD) marker associated with high rooting ability in larch. Two DNA bulks: H (high rooting ability) bulk and L (low rooting ability) bulk were constructed according to the rooting percentages of the stock plants. Among the 328 primers, only S356 could amplify a specific band, named S356₄₄₅, which only existed in the H bulk and was further confirmed following selective genotyping of individual hybrids. Grounded on the border sequences, S356₄₄₅ was converted to a sequence...

Factors influencing shoot multiplication of lotus (Nelumbo nucifera)

S.-Y. Shou, L.-X. Miao, W.-S. Zai, X.-Z. Huang, D.-P. Guo

Biologia plantarum 52:529-532, 2008 | DOI: 10.1007/s10535-008-0103-7

Effect of plant growth regulators, explant size, season of explant collection, temperature (20, 25 and 30 °C) and photoperiod on in vitro lotus (Nelumbo nucifera Gaertn.) shoot formation and growth were examined. Shoots formation was greatly influenced by growth regulators, explant size and season of explant collection. The maximum number of shoots were induced from bud explants on Murashige and Skoog (MS) medium containing 4.44 µM benzyladenine (BA) + 0.54 µM α-naphthalene acetic acid (NAA). Explants formed by bud of one expanded and one unexpanded leaf, which was collected in spring gave encouraging results of shoot...

Hairy root culture of Plumbago indica as a potential source for plumbagin

M. Gangopadhyay, D. Sircar, A. Mitra, S. Bhattacharya

Biologia plantarum 52:533-537, 2008 | DOI: 10.1007/s10535-008-0104-6

Hairy roots of Plumbago indica were established at high frequency (90 %) by infecting leaf explants with Agrobacterium rhizogenes strain ATCC 15834. The axenic root cultures were established under darkness in hormone-free liquid Murashige and Skoog medium containing 3 % sucrose. The highest plumbagin content was found to accumulate in roots at their exponential phase of growth. A low pH (4.6) and a low concentration of sucrose (1 %) were beneficial for root growth in darkness, while pH 5.6 and 3 % sucrose under continuous irradiance enhanced plumbagin accumulation in roots up to 7.8 mg g^-1(d.m.). Direct shoot regeneration from...

An improved protocol for micropropagation of elite genotypes of Simmondsia chinensis (Link) Schneider

A. Singh, M. P. Reddy, J. S. Patolia

Biologia plantarum 52:538-542, 2008 | DOI: 10.1007/s10535-008-0105-5

An efficient micropropagation protocol was developed for elite male and female genotypes of Simmondsia chinensis using nodal segments. Bud initiation was found to be best on Murashige and Skoog's (MS) medium supplemented with 4.44 µM 6-benzylaminopurine (BAP) and 88.8 µM adenine. Upon sub-culture, 10-15 shoots per explant were obtained when 4.44 µM BAP and 74.0 µM adenine were incorporated in the medium. Increase in KNO₃ concentration in the medium improved shoot multiplication rate and in vitro flowering in 20 % of male cultures. Elongated shoots were harvested, pulse treated for 48 h on liquid medium...

Population genetic diversity in the polyploid complex of wheatgrasses using isoenzyme and RAPD data

A. Refoufi, M. A. Esnault

Biologia plantarum 52:543-547, 2008 | DOI: 10.1007/s10535-008-0106-4

Thirty five bands (alleles) from six enzyme systems and fifty seven random amplified polymorphic DNA (RAPD) fragments were selected to analyse the genetic diversity of 33 polyploid wheatgrasses (Triticeae) populations of species Thinopyrum junceiforme and Elytrigia pycnantha, and two hybrids, one pentaploid and one novel 9-ploid. Dice's similarity coefficient, the UPGMA-derived phenograms from RAPD, and allozymes markers showed that the clustering of wheatgrass populations was based on ploidy level. These markers had similar levels of diversity between populations, with high genetic similarity within the same ploidy-level and within...

Protein profiling in F₁ and F₂ generations of two tomato genotypes differing in ripening time

G. R. Rodríguez, L. Sequin, G. R. Pratta, R. Zorzoli, L. A. Picardi

Biologia plantarum 52:548-552, 2008 | DOI: 10.1007/s10535-008-0107-3

Pericarp polypeptide profiles were analyzed at three ripening stages in the F₁ hybrid and the F₂ population from the cross between the accessions: LA1385 (Lycopersicon esculentum var. cerasiforme) and 804627 (L. esculentum, a homozygous genotype for the nor mutant). Six polymorphic polypeptides were observed in LA1385, while no polymorphic polypeptides among ripening stages was observed in 804627. On the other hand, some polypeptides in the F₁ hybrid were not observed in the parents whereas others were present in both parental genotypes and were unnoticeable in the hybrid genotype. From a...

Influences of cefotaxime and carbenicillin on plant regeneration from wheat mature embryos

Y. Yu, Z.-M. Wei

Biologia plantarum 52:553-556, 2008 | DOI: 10.1007/s10535-008-0109-1

The influences of cefotaxime and carbenicillin on regeneration potential of wheat (Triticum aestivum L.) mature embryos were investigated. Filter-sterilized cefotaxime enhanced regeneration capacity although it did not affect the average number of shoots per explant. The highest regeneration capacity of 55.4 % was obtained on regeneration medium supplemented with 100 mg dm^-3 cefotaxime. Filter-sterilized carbenicillin did not stimulate plant regeneration. However, higher concentration (100 mg dm^-3) accelerated callus browning and inhibited the following regeneration. Autoclaved antibiotics at all tested concentrations showed...

In vitro plant regeneration from leaf explants of Ophiorrhiza japonica

G.-Y. Kai, L.-M. Dai, X.-Y. Mei, J.-G. Zheng, W. Wang, Y. Lu, Z.-Y. Qian, G.-Y. Zhou

Biologia plantarum 52:557-560, 2008 | DOI: 10.1007/s10535-008-0110-8

An efficient in vitro plant regeneration system from leaves of Ophiorrhiza japonica Blume was established for the first time. Callus formation rate was more than 90.4 % from leaf segments on Murashige and Skoog (MS) supplemented with either α-naphthaleneacetic acid (NAA) alone or in combination with 6-benzyladenine (BA). The highest shoot regeneration (78.9 %) was achieved on MS medium containing 2.0 mg dm^-3 BA and 0.2 mg dm^-3 NAA, with an average of 9.4 shoots developed per leaf segment. Shoot regeneration was also improved when the leaf explants were cultured in MS basal medium supplemented with 0.5 % (m/v)...

Impact of copper on reactive oxygen species, lipid peroxidation and antioxidants in Lemna minor

S. K. Panda

Biologia plantarum 52:561-564, 2008 | DOI: 10.1007/s10535-008-0111-7

Lemna minor L. treated with 20, 50, or 100 µM CuSO₄ accumulated Cu and reactive oxygen species (hydrogen peroxide and superoxide radical) in frond and root cells. The time-course analysis of lipid peroxidation showed high increment in malondialdehyde production only after 12 and 48 h of Cu treatment. Guaiacol peroxidase and superoxide dismutase activities decreased after 48 h while glutathione reductase activity enhanced 48 h after Cu-treatment. Ascorbate and glutathione contents increased with the increasing Cu stress.

Lead uptake, toxicity and accumulation in Phaseolus vulgaris plants

A. Piechalak, A. Malecka, D. Barałkiewicz, B. Tomaszewska

Biologia plantarum 52:565-568, 2008 | DOI: 10.1007/s10535-008-0112-6

The effects of lead were investigated in bean plants (Phaseolus vulgaris L. cv. Zlota Saxa) grown hydroponically in nutrient solution and exposed to Pb(NO₃)₂ (0.1, 0.5, 1 mM) with or without equimolar concentrations of chelator ethylenediaminetetraacetic acid (EDTA). The roots treated only with Pb(NO₃)₂ accumulated up to 25 g(Pb) kg^-1(d.m.), during 4-d exposure. However, in bean plants exposed to 0.5 mM Pb + 0.5 mM EDTA or 1 mM Pb + 1 mM EDTA 2.5 times less Pb was determined. In bean plants treated only with Pb, less than 6 % of total lead accumulated was transported to the aboveground parts,...

Effect of growth regulators and ethylmethane sulphonate on growth, and chlorophyll, sugar and proline contents in Dracaena sanderiana cultured in vitro

A. Junaid, A. Mujib, M. P. Sharma

Biologia plantarum 52:569-572, 2008 | DOI: 10.1007/s10535-008-0113-5

A high efficient four step protocol (callus initiation, regeneration, shoot elongation and rooting) for in vitro propagation of Dracaena sanderiana Sander ex Mast was developed. Callusing was achieved from nodal stem segment explants treated with various concentrations of ethylmethane sulphonate (EMS) on MS medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D; 1.5 g m^-3). A significant increase in callus induction percentage and biomass production was noticed from lower EMS treated lines (ET₁ and ET₂) comparatively to control and other (ET₃, ET₄ and ET₅)...

Response of the cherry rootstock to water stress induced in vitro

N. Sivritepe, U. Erturk, C. Yerlikaya, I. Turkan, M. Bor, F. Ozdemir

Biologia plantarum 52:573-576, 2008 | DOI: 10.1007/s10535-008-0114-4

The in vitro response of sweet cherry (Prunus cerasus × P. canescens) rootstock Gisela 5 to increasing water deficit in the culture medium was studied. Water stress induced by the incorporation of 1, 2 and 4 % polyethylene glycol (PEG-8000) into the Murashige and Skoog medium was applied for 6 weeks. PEG-induced water stress reduced shoot dry mass, length, water content and relative chlorophyll content. Water stress also induced leaf necrosis without causing loss of viability in the explants. The increase in malondialdehyde content indicated oxidative stress. The activities of antioxidant enzymes, such as superoxide dismutase (SOD),...

Stomatal and chlorophyll fluorescence characteristics in European beech cultivars during leaf development

I. Čaňová, J. Ďurkovič, D. Hladká

Biologia plantarum 52:577-581, 2008 | DOI: 10.1007/s10535-008-0115-3

Changes in stomatal and chlorophyll fluorescence characteristics were analyzed in the course of leaf expansion in European beech (Fagus sylvatica L.) cultivars Aurea Pendula, Cristata, Rohanii, Rotundifolia and Viridivariegata. Stomatal length increased gradually from the second to the fifth phenological stage. Rotundifolia reached the highest mean stomatal length whereas Aurea Pendula and Cristata had the lowest values. Stomatal density for all cultivars decreased from the second to the fifth stage. Aurea Pendula reached the highest stomatal density in all phenological stages. The highest values of variable to maximum fluorescence ratio (F_v/F_m)...

Control of fusarium wilt of Solanum melongena by Trichoderma spp.

M. R. Chakraborty, N. C. Chatterjee

Biologia plantarum 52:582-586, 2008 | DOI: 10.1007/s10535-008-0116-2

Biological control of wilt of egg plant (Solanum melongena L.) caused by Fusarium solani was made with the application of five Trichoderma species, T. harzianum, T. viride, T. lignorum, T. hamatum and T. reesei. The effect of volatile and non-volatile antibiotics of Trichoderma origin on growth inhibition of the wilt pathogen was studied. T. harzianum showed maximum growth inhibition (86.44 %) of the pathogen through mycoparasitism. The non-volatiles produced by the Trichoderma species exhibited 100 % growth inhibition of the pathogen under in vitro condition. Production of siderophores...

Role of nitric oxide under saline stress: implications on proline metabolism

A. I. López-Carrión, R. Castellano, M. A. Rosales, J. M. Ruiz, L. Romero

Biologia plantarum 52:587-591, 2008 | DOI: 10.1007/s10535-008-0117-1

The present work is focused on the possible relationship between nitric oxide and the induction of proline in response to salt stress. The plants were subjected to 100 mM NaCl and sodium nitroprusside (SNP; the donor of NO) at different concentrations. The plants showed lower NaCl-induced oxidative stress and proline accumulation after application of low concentrations of SNP together with the NaCl treatment. The reduction in the proline content was related to increased activity of proline dehydrogenase. These results suggest that the NO could be capable of mitigating damage associated with salt stress.

Effects of silicon on defense of wheat against oxidative stress under drought at different developmental stages

H. J. Gong, K. M. Chen, Z. G. Zhao, G. C. Chen, W. J. Zhou

Biologia plantarum 52:592-596, 2008 | DOI: 10.1007/s10535-008-0118-0

The effects of silicon application before sowing on the drought-induced oxidative stress and antioxidant defense in wheat (Triticum aestivum L.) were investigated. Drought stress was applied by withholding watering till sampling at booting or filling stage. Application of Si increased the water potential of drought-stressed plants at filling stage, whereas it did not at booting stage. The superoxide dismutase (SOD) activity was inhibited and peroxidase (POD) activity was enhanced by drought at booting stage, and no differences were observed due to the Si treatment. At filling stage, however, application of Si increased the SOD activity and decreased...

Promotion of direct somatic embryogenesis of Oncidium by adjusting carbon sources

P. I. Hong, J. T. Chen, W. C. Chang

Biologia plantarum 52:597-600, 2008 | DOI: 10.1007/s10535-008-0119-z

To further optimize a culture medium for induction of direct embryo formation of Oncidium cvs. Gower Ramsey and Sweet Sugar, five kinds of carbon sources, cellibiose, fructose, glucose, maltose and sucrose at 10, 20, 30 and 60 g dm^-3 were tested in this study. Cellibiose supply had an inhibitory effect and resulted in high percentage of explant browning in both cultivars. By contrast, fructose, glucose and sucrose were all effective for direct embryo induction. In cv. Gower Ramsey, the suitable ranges of concentration were found at 30-60 g dm^-3 of sucrose, 10-20 g dm^-3 of glucose and 20-30 g dm^-3 of...