Biologia plantarum, 2011 (vol. 55), issue 1

Article

Micropropagation of Zingiber rubens and assessment of genetic stability through RAPD and ISSR markers

S. Mohanty, M. K. Panda, S. Sahoo, S. Nayak

Biologia plantarum 2011, 55:16-20 | DOI: 10.1007/s10535-011-0002-1

Protocol was developed for high frequency in vitro multiplication of an endemic species, Zingiber rubens Roxb. The sprouted buds of the rhizomes were cultured on Murashige and Skoog (MS) medium supplemented with 6-benzyladenine (BA; 0.5-5.0 mg dm^-3), indole-3-acetic acid (IAA; 0.5-2.0 mg dm^-3), kinetin (KIN; 1.0-3.0 mg dm^-3), naphthaleneacetic acid (NAA; 0.5-1.0 mg dm^-3) and adenine sulphate (ADS; 80-100 mg dm^-3). MS basal medium supplemented with 3 mg dm^-3 BA and 0.5 mg dm^-3 IAA was optimum for shoot elongation. The elongated shoots (1-2 cm) were transferred...

A two-step protocol for shoot regeneration from hypocotyl explants of oilseed rape and its application for Agrobacterium-mediated transformation

G. -X. Tang, K. Knecht, X. -F. Yang, Y. -B. Qin, W. -J. Zhou, D. Cai

Biologia plantarum 2011, 55:21-26 | DOI: 10.1007/s10535-011-0003-0

A two-step protocol for improving the frequency of shoot regeneration from oilseed rape (Brassica napus L.) hypocotyl explants was established. The protocol consists of a pre-culture on callus induction medium (CIM) and a subsequent shoot regeneration on shoot induction medium (SIM). The SIM was Murashige and Skoog medium supplemented with different concentrations of 6-benzylaminopurine (BA; 2-5 mg dm^-3) and naphthaleneacetic acid (NAA; 0.05-0.15 mg dm^-3). Maximum frequency of shoot regeneration (13 %) was on the SIM medium containing 4 mg dm^-3 BA and 0.1 mg dm^-3 NAA, but it increased to 24.45 % when...

Silencing of the LeSGR1 gene in tomato inhibits chlorophyll degradation and exhibits a stay-green phenotype

Z.-L. Hu, L. Deng, B. Yan, Y. Pan, M. Luo, X.-Q. Chen, T.-Z. Hu, G.-P. Chen

Biologia plantarum 2011, 55:27-34 | DOI: 10.1007/s10535-011-0004-z

The full-length cDNA of LeSGR1 was cloned from tomato by RT-PCR and RACE. The cDNA encoded a protein of 272 amino acid residues and was deposited in GenBank (accession No. DQ100158). Northern analysis suggests that LeSGR1 gene specifically expresses in senescent leaves and mature fruits of tomatoes. Desiccation and flooding induce the expression of LeSGR1 in tomato leaves and stems. Both in ethylene-insensitive mutants (Nr) and ripening inhibitor mutants (rin), the expression of LeSGR1 is markedly decreased compared with that in the wild type. Alignment of the nucleotide sequence of SGR1 cloned...

Expression profiles of PtrLOS2 encoding an enolase required for cold-responsive gene transcription from trifoliate orange

D. C. Liu, L. G. He, H. L. Wang, M. Xu, Z. H. Sun

Biologia plantarum 2011, 55:35-42 | DOI: 10.1007/s10535-011-0005-y

Low expression of osmotically responsive genes 2 (LOS2) encodes an enolase (2-phospho-D-glycerate hydrolase, EC 4.2.1.11) that converts 2-phospho-D-glycerate (PGA) to phosphoenolpyruvate (PEP) in the glycolytic pathway in Arabidopsis. Meanwhile, it is a transcriptional activator of cold-responsive gene, negatively controlling the expression of STZ/ZAT10, a zinc finger transcriptional repressor of cold-responsive gene from Arabidopsis. A novel LOS2 gene, designated PtrLOS2 (GenBank accession number GQ144341), was isolated from trifoliate orange [Poncirus trifoliata (L.) Raf.]. The PtrLOS2 cDNA...

Sugarcane genes differentially expressed during water deficit

F. A. Rodrigues, J. P. Da Graça, M. L. De Laia, A. Nhani-Jr, J. A. Galbiati, M. I. T. Ferro, J. A. Ferro, S. M. Zingaretti

Biologia plantarum 2011, 55:43-53 | DOI: 10.1007/s10535-011-0006-x

To identify genes that are up and down-regulated by water deficit in sugarcane we used the macroarray methodology and the expression level of 3 575 independent sugarcane cDNAs was measured by hybridization with RNA extracted from plants submitted to mild, moderate and severe water deficit. We identified approximately 1 670 differentially expressed genes from which 62 % were up-regulated by different stress-conditions, whereas many repressed genes were exclusive for each time-point. Analysis of similarity showed that approximately 24 % of the differentially expressed genes shared homology with proteins involved in different processes such as signal...

RFLP mapping of loci controlling self-incompatibility in Brassica campestris and their comparative mapping with B. napus and B. oleracea

J. Panigrahi, P. Kole, C. Kole

Biologia plantarum 2011, 55:54-60 | DOI: 10.1007/s10535-011-0007-9

RFLP analysis of a cDNA probe SLG6, governing self incompatibility (SI) in Brassica oleracea, using a recombinant inbred population of Brassica campestris followed by genetic linkage analysis led to the detection of two marker loci, SLG6a and SLG6b controlling SI. SLG6a was mapped in linkage group (LG) 9 and was flanked by the RFLP markers ec4f10 (6.4 cM) and wg5b9 (4.2 cM). SLG6b positioned in LG 2 and was flanked by the RFLP markers wg2d11 (9.9 cM) and ec4e7 (26.9 cM). These results indicated the scope of marker-aided introgression of these genes into self-compatible genotypes...

Molecular cloning and characterization of nitrogen source responsive GS1 gene from melon

Y. -W. Deng, Y. -D. Zhang, S. -Q. Guan, Y. Chen, W. Jiang, D. -M. Tang, D. -F. Huang

Biologia plantarum 2011, 55:61-67 | DOI: 10.1007/s10535-011-0008-8

A full-length cDNA clone encoding cytosolic glutamine synthetase (GS1; EC 6.3.1.2) was isolated from melon (Cucumis melo L.) for the first time by RT-PCR and RACE approach. The clone, designated as M-GS1 (accession No. DQ851867), contains 1494 nucleotides with an open reading frame (ORF) of 1068 nucleotides. The deduced 356 amino acid sequence showed high similarity with previously reported GS1s from various plant species. Sequence analysis revealed that the predicted protein contains a GS β-Grasp domain, a GS catalytic domain, and the main conserved motifs characteristic of a plant GS1. The phylogenetic analysis displayed that M-GS1...

Maternal origin, genome constitution and evolutionary relationships of polyploid Elymus species and Hordelymus europaeus

Y. Ni, N. Asamoah-Odei, G. Sun

Biologia plantarum 2011, 55:68-74 | DOI: 10.1007/s10535-011-0009-7

The trnS/psbC region of chloroplast DNA (cpDNA) was sequenced for 18 Elymus polyploid species, Hordelymus europaeus and their putative diploid ancestors. The objective was to determine the maternal origin and evolutionary relationships of these polyploid taxa. Phylogenetic analysis showed that Elymus and Pseudoroegneria species formed a highly supported monophyletic group (100 % bootstrap values), suggesting that Pseudoroegneria is the maternal genome donor to polyploid Elymus species studied here. The phylogenetic tree based on cpDNA sequence data indicates that E. submuticus contains...

Characterization of Mg-dechelating substance in senescent and pre-senescent Arabidopsis thaliana leaves

A. M. Büchert, P. M. Civello, G. A. Martínez

Biologia plantarum 2011, 55:75-82 | DOI: 10.1007/s10535-011-0010-1

The removal of Mg²⁺ is an important step in the chlorophyll degradation pathway and extracts from senescent and presenescent Arabidopsis thaliana leaves were analyzed for Mg-dechelatase activity, using chlorophyllin, an artificial derivative of the natural substrate, chlorophyllide. The optimum temperature and pH for this reaction were determined to be at approximately 50 °C and 7.2, respectively. Mg-dechelatase activity was enhanced by addition of EDTA and inhibited by MgCl₂, HgCl₂ and reduced glutathione, indicating phenomenons such as retroinhibition by reaction products and dependence on the redox state of...

Photosynthesis and chlorophyll fluorescence response to low sink demand of tubers and roots in Dahlia pinnata source leaves

S. T. Yan, X. D. Li, W. D. Li, P. G. Fan, W. Duan, S. H. Li

Biologia plantarum 2011, 55:83-89 | DOI: 10.1007/s10535-011-0011-0

Photosynthetic rate (P_N) and chlorophyll (Chl) fluorescence induction of source leaves in response to a low sink demand created by girdling the branch (GB) between the root-tuber-system and the leaves were studied in Dahlia pinnata L. cv. Rigolet during the stage of rapid tuber growth in the greenhouse. GB resulted in significantly lower values of P_N, stomatal conductance (g_s), and transpiration rate (E), but in higher leaf temperature (T_l) compared with those of controls. With exception of maximum quantum yield of photosystem 2 (PS 2) photochemistry (F_v/F_m) and maximum ratio...

Variability of photosynthetic capacity and water relations of Pinus sylvestris L. in the field

U. Lüttge, P. Escher, R. Paluch, H. Pfanz, C. Wittmann, H. Rennenberg, K. Rakowski

Biologia plantarum 2011, 55:90-98 | DOI: 10.1007/s10535-011-0012-z

Measurements of dependence of photosynthetic electron transport on irradiance and analyses of stable isotope ratios (δ¹⁸O, δ¹³C, δ¹⁵N) were performed on 4 to 6-year-old pine trees (Pinus sylvestris L.) in the primeval forest reserve of Białowieża and on 21-year-old pine trees of a plantation of different provenances at the Sękocin Forest Station near Warsaw, Poland. Small differences in maximum photosynthetic electron transport rates, ETR_max were related to growth. Stable isotope analyses suggest that water relations play an important role for the performance of P. sylvestris...

Genotypic variation in photosynthesis in cacao is correlated with stomatal conductance and leaf nitrogen

A. J. Daymond, P. J. Tricker, P. Hadley

Biologia plantarum 2011, 55:99-104 | DOI: 10.1007/s10535-011-0013-y

Variation in photosynthetic parameters was observed between eight contrasting cacao (Theobroma cacao) genotypes. Net photosynthetic rate (P_N) ranged from 3.4 to 5.7 μmol(CO₂) m^-2 s^-1 for the genotypes IMC 47 and SCA 6, respectively. Furthermore, genotypic differences were detected in quantum efficiency ranging from 0.020 to 0.043 μmol(CO₂) μmol^-1(photon) for UF 676 and AMAZ 15/15, respectively. Differences in PN were correlated with both stomatal conductance (g_s) and leaf nitrogen per unit area. Some variation in water use efficiency was observed between genotypes,...

Combined drought and heat stress in wheat: changes in some heat shock proteins

B. Grigorova, I. Vaseva, K. Demirevska, U. Feller

Biologia plantarum 2011, 55:105-111 | DOI: 10.1007/s10535-011-0014-x

The influence of combined and individually applied drought and heat stress was studied in two wheat (Triticum aestivum L.) cultivars: resistant cv. Katya and susceptible cv. Sadovo. Relative water content decreased and electrolyte leakage increased due to individual and combined application of both stresses. Initial heat shock protein profile has been outlined via SDS electrophoresis of leaf extracts. The results obtained were confirmed by immunoblotting with anti-HSP70 monoclonal antibodies, anti-HSP110 polyclonal antibodies and anti-α β-crystalline polyclonal antibodies. The effect of simultaneously applied water stress and...

Effects of jasmonate and some other signalling factors on bean and onion growth during the initial phase of cadmium action

W. Maksymiec

Biologia plantarum 2011, 55:112-118 | DOI: 10.1007/s10535-011-0015-9

Short-time direct and indirect effects of 25 μM Cd on the growth of dicotyledon (Phaseolus coccineus) and monocotyledon (Allium cepa) plants were investigated in the presence of inhibitors of ethylene synthesis, NADPH oxidase, and the octadecanoid pathway. Only 5 min-long action of Cd was enough for inhibition of growth in bean roots, but its recovery time was extended to several days. After 7 h treatment, Cd was significantly accumulated in bean roots, but maximum H₂O₂ accumulation was seen after 1 h. Cd-induced H₂O₂ accumulation decreased especially after addition of ethylene inhibitor...

Characterization of a type 3 metallothionein isolated from Porteresia coarctata

B. Usha, N. S. Keeran, M. Harikrishnan, K. Kavitha, A. Parida

Biologia plantarum 2011, 55:119-124 | DOI: 10.1007/s10535-011-0016-8

Metallothioneins are involved in detoxification of heavy metals. A cDNA encoding type 3 metallothionein (PcMT3) was isolated from the salt stressed leaf cDNA library of Porteresia coarctata (Roxb.) Tateoka (wild rice) that grows well in the heavy metal laden estuarine soils. The PcMT3 cDNA (581 bp) encodes a protein of 64 amino acids. PcMT3 is highly homologous (82 %) to OsMT-I-3a of rice, but is unique from other type 3 plant MTs due to the presence of an additional glycine residue in the C-terminal domain. Analysis of the 5' upstream region of PcMT3 showed the presence of cis-acting elements like the CG box and...

Glutathione in adaptation of Arabidopsis thaliana to cadmium stress

M. Wójcik, A. Tukiendorf

Biologia plantarum 2011, 55:125-132 | DOI: 10.1007/s10535-011-0017-7

The role of glutathione (GSH) in the adaptation of wild type Arabidopsis thaliana plants to Cd stress was investigated. The nutrient solution (control or containing 50 or 100 μM Cd) was supplemented with buthionine sulfoximine (BSO; 50, 100, 500 μM, to decrease the GSH content in plants) or GSH (50, 100, 500 μM, to increase its content in plants) in order to find how GSH content could regulate Cd stress responses. BSO application did not influence plant biomass, while exogenous GSH (especially 500 μM) reduced root biomass. BSO (500μM) in combination with Cd (100 μM) increased Cd toxicity on root growth (by over 50 %), most...

Strategies of cadmium and zinc resistance in willow by regulation of net accumulation

T. Landberg, P. Jensén, M. Greger

Biologia plantarum 2011, 55:133-140 | DOI: 10.1007/s10535-011-0018-6

This work was performed to find out if metal resistant clones of Salix viminalis L. are capable to achieve high resistance to the metals by regulating their net accumulation. Salix clones with low or high resistance in combination with low or high accumulation capacity of either Zn or Cd were cultivated from cuttings in nutrient solution. The investigation included leakage and uptake experiments using ⁶⁵Zn or ¹⁰⁹Cd and analysis of root cation exchange capacity (CEC). Some plants were pre-treated with unlabeled 0.5 μM Cd or 2.5 μM Zn 24 h prior to the experiments to induce possible tolerance mechanisms. To find...

An apoplastic chitinase CpCHT1 isolated from the corolla of wintersweet exhibits both antifreeze and antifungal activities

S. -H. Zhang, Y. Wei, J. -L. Liu, H. -M. Yu, J. -H. Yin, H. -Y. Pan, T. C. Baldwin

Biologia plantarum 2011, 55:141-148 | DOI: 10.1007/s10535-011-0019-5

The shrub Chimonanthus praecox L. (wintersweet) which is native to Chinese montane forests produces its flowers in the midst of winter. This indicates that the floral organs of this species are adapted to growth and development under freezing temperatures. Here, we report the isolation and preliminary characterisation of a 33 kDa apoplastic antifreeze chitinase (CpCHT1) from the petals and its corresponding cDNA. The chitinase activity of CpCHT1 was confirmed by activity staining. Antifreeze activity was validated in terms of the formation of bipyramidal ice crystals and high thermal-hysteresis values. CpCHT1 was also found to affect the germination...

Reviews

Problems and possibilities of monocot transformation

P. Sood, A. Bhattacharya, A. Sood

Biologia plantarum 2011, 55:1-15 | DOI: 10.1007/s10535-011-0001-2

Biotechnological improvement of monocots is often hampered by the lack of efficient regeneration systems, requisite wound responses and low cell competence. Despite these limitations, the biolistic and Agrobacterium methods have been successfully used to produce several transgenic monocots by adjusting the parameters that govern efficient delivery and integration of transgene(s) into plant genome. It is now possible to transform even difficult monocots using tailor-made gene constructs and promoters, suitable A. tumefaciens strains and a proper understanding of the entire process. This success has been reviewed in the present article...

Brief Communications

Morphology and glandular activity of unicellular trichomes of Epilobium hirsutum

S. Strgulc Krajšek, S. Kreft, A. Kladnik, K. Drašlar, N. Jogan, M. Dermastia

Biologia plantarum 2011, 55:149-152 | DOI: 10.1007/s10535-011-0020-z

The unusual glandular trichomes of willow-herbs (Epilobium hirsutum L.) were investigated. They are unicellular, without a specialized basal cell at the layer of the epidermis. They have a cutinized cell wall, a prominent and heavily cutinized wall thickening at the base, and a protruding pore on the top. Among other compounds they contain several flavonoids, e.g. quercitrin and myricitrin. Flavonoids were localized inside the upper part of the trichome cell and most likely were not excreted through the trichome pore.

Protein changes during programmed cell death in tobacco

I. Chaves, M. Alves, D. Carrilho, M. C. Duque-Magalhães, C. P. Ricardo, A. P. Regalado

Biologia plantarum 2011, 55:153-158 | DOI: 10.1007/s10535-011-0021-y

Programmed cell death (PCD) was induced by the Yariv reagent in Nicotiana tabacum cv. Bright Yellow-2 cell suspension. The analyses of proteins extracts by 2-D electrophoresis clearly show massive protein degradation which was mainly due to cysteine protease activity. In contrast, some proteins remained unchanged up to 72 h after PCD induction. Peptide mass fingerprints of these proteins, obtained by MALDI-TOF, identified calreticulin, heat shock protein (HSP) 60, HSP70, malate dehydrogenase and mitochondrial ATP synthase β-subunit.

Effect of salt stress on gene expression of superoxide dismutases and copper chaperone in Arabidopsis thaliana

H. Attia, N. Karray, N. Msilini, M. Lachaâl

Biologia plantarum 2011, 55:159-163 | DOI: 10.1007/s10535-011-0022-x

Arabidopsis thaliana plants (wild type accessions Col and N1438) were grown in nutrient solution for 34 d with or without 50 mM NaCl. Salt stress inhibited plant growth rate more in Col than in N1438 and a decrease in K⁺, Ca²⁺ and nitrogen contents was observed in both accessions. NaCl diminished accumulation of malate, fumarate and citrate only in Col accession. To measure the effect of NaCl on transcript level of superoxide dismutase (SOD) isoforms and copper chaperone for SOD genes, a semi-quantitative polymerase chain reaction (RT-PCR) method was developed using cDNA normalized against the EF1a gene in parallel...

In vitro cloning of Azadirachta indica from root explants

K. Arora, M. Sharma, J. Srivastava, S. A. Ranade, A. K. Sharma

Biologia plantarum 2011, 55:164-168 | DOI: 10.1007/s10535-011-0023-9

In vitro cultures of Azadirachta indica A. Juss. were raised by first culturing the root segments on modified Murashige and Skoog (MS) medium supplemented with 8.88 μM 6-benzylaminopurine (BAP), 9.84 μM N⁶-(2-isopentenyl) adenine (2iP), 5.71 μM indole-3-acetic acid (IAA), 81.43 μM adenine hemisulphate and 2.27 μM putrescine for 2 d followed by their transfer to the same medium except containing one-tenth of the initially used concentrations of BAP, 2iP and IAA. The regenerated shoots sustained proliferation in the basal medium supplemented with 1.11 μM BAP, 1.43 μM IAA and 135.72 μM adenine hemisulphate....

In vitro regeneration of an endangered medicinal plant Picrorhiza scrophulariiflora

P. Bantawa, O. Saha-Roy, S. Kumar Ghosh, T. Kumar Mondal

Biologia plantarum 2011, 55:169-172 | DOI: 10.1007/s10535-011-0024-8

A reproducible in vitro regeneration system for Nepalese kutki (Picrorhiza scrophulariiflora Pennell) was developed from in vitro leaf derived callus. Induction of more than seven shoot buds per explant was achieved on Woody plant medium (WPM) supplemented with 0.53 μM α-napthaleneacetic acid (NAA) and 0.23 μM kinetin (KIN). The shoots were elongated on WPM supplemented with 0.44 μM 6-benzylaminopurine (BAP) and rooted on WPM supplemented with 5.3 μM NAA within 2 weeks. The random amplified polymorphic DNA (RAPD) analysis indicated genetic uniformity of the micropropagated plants with its donor plants.

Subcellular localization of rice hexokinase (OsHXK) family members in the mesophyll protoplasts of tobacco

W. Cheng, H. Zhang, X. Zhou, H. Liu, Y. Liu, J. Li, S. Han, Y. Wang

Biologia plantarum 2011, 55:173-177 | DOI: 10.1007/s10535-011-0025-7

Hexokinase (HXK, EC 2.7.1.1) plays an important role in the metabolism and glucose signalling. To examine the characteristics of HXK gene family in rice, the subcellular localizations of ten hexokinases (OsHXK1 - OsHXK10) were determined using OsHXK::GFP fusion proteins in tobacco mesophyll protoplasts. As was previously demonstrated, OsHXK4 was detected in the chloroplast stroma, OsHXK5 and OsHXK6 in the mitochondria, and OsHXK7 and OsHXK10 in the cytoplasm. In the present study, OsHXKs were clearly divided into three types (A, B, C) based on their N-terminal sequences. The new type-C HXKs in plants, OsHXK1, OsHXK7 and OsHXK8,...

Effect of aluminum on the in vitro activity of acid phosphatases of four potato clones grown in three growth systems

L. A. Tabaldi, D. Cargnelutti, G. Y. Castro, J. F. Gonçalves, R. Rauber, D. A. Bisognin, M. R. C. Schetinger, F. T. Nicoloso

Biologia plantarum 2011, 55:178-182 | DOI: 10.1007/s10535-011-0026-6

The aim of this study was to assess the effect of aluminum on the in vitro activity of acid phosphatases (APases) of four potato clones, Macaca and Dakota Rose (Al-sensitive), and SMIC148-A and Solanum microdontum (Al-tolerant), grown in vitro, in hydroponics or in a greenhouse. The enzyme was assayed in vitro in the presence of 0, 1.85, 3.70, 5.55 and 7.40 mM Al. In plantlets grown in vitro, root APases were inhibited by Al in all clones, while shoot APases were inhibited by Al in S. microdontum and Dakota Rose and increased in Macaca at all Al concentrations. In plantlets grown in hydroponics, root APases...

Influence of irradiance on chlorophyll synthesis in Picea abies calli cultures

R. Balážová, A. Blehová, V. Demko, K. Breznenová, J. Hudák

Biologia plantarum 2011, 55:183-186 | DOI: 10.1007/s10535-011-0027-5

Dark-grown seedlings of Picea abies (L) Karst. are able to accumulate the highest amounts of chlorophyll (Chl) and its precursor protochlorophyllide (Pchlide) in all Pinaceae, but calli derived from 14-d-old green cotyledons of P. abies are completely white during the cultivation in the dark. Pchlide reduction is catalysed in the dark by light-independent protochlorophyllide oxidoreductase (DPOR). This enzyme complex consists of three protein subunits ChlL, ChlN and ChlB, encoded by three plastid genes chlL, chlN and chlB. Using semiquantitative RT-PCR, we observed very low expression of chlLNB genes...

Effects of cadmium on gas exchange and phytohormone contents in citrus

M. F. López-Climent, V. Arbona, R. M. Pérez-Clemente, A. Gómez-Cadenas

Biologia plantarum 2011, 55:187-190 | DOI: 10.1007/s10535-011-0028-4

The effect of increased Cd²⁺ concentrations in the watering solution on citrus physiology was studied by using two citrus genotypes, Cleopatra mandarin and Carrizo citrange. Cadmium content in roots and leaves was tested together with measurements of leaf damage, gas exchange parameters, and hormonal contents. Citrus roots efficiently retained Cd²⁺ avoiding its translocation to the shoots and Cleopatra mandarin translocated less Cd²⁺ than Carrizo. With increasing Cd²⁺ concentration all gas exchange parameters were decreased more in Carrizo than in Cleopatra mandarin. Cd-induced increases in abscisic acid...

Response of antioxidant enzymes to high NaCl concentration in different salt-tolerant plants

S. Mallik, M. Nayak, B. B. Sahu, A. K. Panigrahi, B. P. Shaw

Biologia plantarum 2011, 55:191-195 | DOI: 10.1007/s10535-011-0029-3

The effects of NaCl on the H₂O₂ content and the activities of catalase (CAT) and superoxide dismutase (SOD) were studied in diverse group of plants, such as a unicellular alga, Chlorella sp., an aquatic macrophyte, Najas graminea, and a mangrove plant, Suaeda maritima, all showing high tolerance to NaCl. Significant accumulation of H₂O₂ was observed in all the tested plants upon their exposure to 255 mM NaCl. The activity of both CAT and SOD increased significantly in response to the NaCl treatment. Growing the plants in presence of 255 mM NaCl also resulted in the synthesis of new isoforms...

The effects of abiotic stresses on the NADP-dependent malic enzyme in the leaves of the hexaploid wheat

Z. Y. Fu, Z. B. Zhang, Z. H. Liu, X. J. Hu, P. Xu

Biologia plantarum 2011, 55:196-200 | DOI: 10.1007/s10535-011-0030-x

The objective of this study was to examine the effects of different abiotic stresses on the activity of an NADP-dependent malic enzyme (NADP-ME) and the corresponding gene transcription in the leaves of the hexaploid wheat (Triticum aestivum L.) The activity of the NADP-ME enzyme was increased by water stress (20 % polyethylene glycol 6000), low temperature (4 °C), darkness, salinity (200 mM NaCl), abscisic acid and salicylic acid. The transcription of the TaNADP-ME1 gene decreased in response to all of the stresses except darkness and NaCl. In addition, the transcription of TaNADP-ME2 was down-regulated by all of the tested treatments...