for Journals by Title or ISSN
for Articles by Keywords
help

Publisher: Elsevier   (Total: 3040 journals)

 A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  

The end of the list has been reached or no journals were found for your choice.
Journal Cover Plant Physiology and Biochemistry
  [SJR: 1.167]   [H-I: 84]   [7 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0981-9428
   Published by Elsevier Homepage  [3040 journals]
  • Arsenic-induced genotoxic responses and their amelioration by diphenylene
           iodonium, 24-epibrassinolide and proline in Glycine max L.
    • Authors: Vibhuti Chandrakar; Bhumika Yadu; Rakesh Kumar Meena; Amit Dubey; S. Keshavkant
      Pages: 74 - 86
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Vibhuti Chandrakar, Bhumika Yadu, Rakesh Kumar Meena, Amit Dubey, S. Keshavkant
      Presence of the toxic metalloid, “arsenic (As)” is ubiquitous in the environment especially in the soil and water. Its excess availability in the soil retards growth and metabolism of plants via (a) slowing down the cell division/elongation, (b) overproduction of reactive oxygen species (ROS), (c) modulation of antioxidant enzymes, and (d) alteration of DNA profile/genomic template stability (GTS). In the current study, diphenylene iodonium (DPI), 24-epibrassinolide (EBL) and proline (Pro) were used to analyze their roles in eliminating the adverse effects of As. Glycine max L. (variety JS 335) seeds were subjected to As (75 μM, Sodium arsenite was used as source of As), and in combination with DPI (10 μM), EBL (0.5 μM) or Pro (10 mM), for five consecutive days, and effects of these treatment combinations were analyzed on germination percentage, biomass, membrane stability, GTS and expressions of defensive genes. In addition, the levels of As, ROS, malondialdehyde, DNA content, oxidation, fragmentation, polymorphism, DNase activity, endogenous Pro and pyrroline-5-carboxylate synthetase activity were evaluated. The results indicated that the treatments of DPI, EBL or Pro are capable to alleviate detrimental effects of As, gauged from above variables, but with different magnitudes. Apropos As-stress mitigation, Pro was found to be the most effective under the confines of the study protocol. This study certainly provides new ideas for intensifying studies to unravel elusive central mechanism of amelioration involving use of DPI, EBL or Pro in plants with confirmed As-toxicity.

      PubDate: 2017-01-08T09:12:38Z
      DOI: 10.1016/j.plaphy.2016.12.023
      Issue No: Vol. 112 (2017)
       
  • A comparative study of the dynamic accumulation of polyphenol components
           and the changes in their antioxidant activities in diploid and tetraploid
           Lonicera japonica
    • Authors: Dexin Kong; Yanqun Li; Mei Bai; Yali Deng; Guangxin Liang; Hong Wu
      Pages: 87 - 96
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Dexin Kong, Yanqun Li, Mei Bai, Yali Deng, Guangxin Liang, Hong Wu
      Polyploidization is an effective method to achieve a higher yield of secondary metabolism active ingredients in medicinal plants. Polyphenols are the main active substances that contribute to the antioxidant activity of Lonicera japonica. For studying on the effect of chromosome doubling and harvest time on the dynamic accumulation of the main active substances and antioxidant capabilities of L. japonica, the polyphenol composition contents (7 phenolic acids and 3 flavonoids) and the antioxidant capacity in buds and flowers of diploid and tetraploid L. japonica at six different growth stages were determined by HPLC-DAD and three common antioxidant assays (FRAP, OH RSC and DPPH ARP), and the correlation between the dynamic accumulation of the polyphenol components and antioxidant capacity was also analyzed in current research. The results indicated that the content of the most determined phenolic acids and flavonoids and the antioxidant capacity in most of the growth stages from tetraploid plants were significantly higher than those in the diploid plants. Furthermore, the changes in the antioxidant activity presented a significant positive correlation with the variations in the chlorogenic acid, rutin, hyperoside, luteoloside in the two ploidy levels of L. japonica plants. The higher yields of chlorogenic acid (158.97, 164.00, 199.85 mg), luteoloside (5.44, 4.03, 6.31 mg), hyperoside (1.15, 1.06, 1.30 mg) and total flavonoids (9.87, 8.67, 11.10 mg) from 100 buds or flowers in tetraploid plants occurred during the S3–S5 stages, and these stages also exhibited higher antioxidant activities. Therefore, the stages of S3–S5 are recommended as the best time for harvesting high-yield, high-quality tetraploid Flos Lonicerae Japonicae.

      PubDate: 2017-01-08T09:12:38Z
      DOI: 10.1016/j.plaphy.2016.12.027
      Issue No: Vol. 112 (2017)
       
  • Transcriptome profiling of sweetpotato tuberous roots during low
           temperature storage
    • Authors: Chang Yoon Ji; Won-Hyong Chung; Ho Soo Kim; Won Yong Jung; Le Kang; Jae Cheol Jeong; Sang-Soo Kwak
      Pages: 97 - 108
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Chang Yoon Ji, Won-Hyong Chung, Ho Soo Kim, Won Yong Jung, Le Kang, Jae Cheol Jeong, Sang-Soo Kwak
      Sweetpotato [Ipomoea batatas (L.) Lam] is a globally important root crop with high industrial value. However, because sweetpotato tuberous roots undergo chilling injuries that negatively affect their quality at temperatures below 10 °C, postharvest damage during the winter season is a major constraint for industrialization. To understand chilling injury response during postharvest low temperature storage, we used next-generation sequencing technology to comprehensive analyze the transcriptome of tuberous roots stored at optimal (13 °C) or low temperature (4 °C) for 6 weeks. From nine cDNA libraries, we produced 298,765,564 clean reads, which were de novo assembled into 58,392 unigenes with an average length of 1100 bp. A total of 3216 differentially expressed genes (DEGs) were detected and categorized into six clusters, of which clusters 2, 4, and 5 (1464 DEGs) were up-regulated under low temperature. The genes in these three clusters are involved in biosynthesis of unsaturated fatty acids, pathogen defense, and phenylalanine metabolism. By contrast, genes in clusters 1, 3, and 6 (1752 DEGs), which were generally down-regulated at low temperature, encode antioxidant enzymes or are involved in glycerophospholipid, carbohydrate, or energy metabolism. We confirmed the results of the transcriptome analysis by quantitative RT-PCR. Our transcriptome analysis will advance our understanding of the comprehensive mechanisms of chilling injury during low temperature storage and facilitate improvements in postharvest storage of sweetpotato tuberous roots.

      PubDate: 2017-01-08T09:12:38Z
      DOI: 10.1016/j.plaphy.2016.12.021
      Issue No: Vol. 112 (2017)
       
  • Pb low doses induced genotoxicity in Lactuca sativa plants
    • Authors: S. Silva; P. Silva; H. Oliveira; I. Gaivão; M. Matos; O. Pinto-Carnide; C. Santos
      Pages: 109 - 116
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): S. Silva, P. Silva, H. Oliveira, I. Gaivão, M. Matos, O. Pinto-Carnide, C. Santos
      Soil and water contamination by lead (Pb) remains a topic of great concern, particularly regarding crop production. The admissible Pb values in irrigation water in several countries range from ≈0.1 to ≈5 mg L−1. In order to evaluate putative effects of Pb within legal doses on crops growth, we exposed Lactuca sativa seeds and seedlings to increasing doses of Pb(NO3)2 up to 20 mg L−1. The OECD parameter seed germination and seedling/plant growth were not affected by any of the Pb-concentrations used. However, for doses higher than 5 mg L−1 significant DNA damage was detected: Comet assay detected DNA fragmentation at ≥ 5 mg L−1 and presence of micronuclei (MN) were detected for 20 mg L−1. Also, cell cycle impairment was observed for doses as low as 0.05 mg L−1 and 0.5 mg L−1 (mostly G2 arrest). Our data show that for the low doses of Pb used, the OECD endpoints were not able to detect toxicity, while more sensitive endpoints (related with DNA damage and mitotic/interphase disorders) identified genotoxic and cytostatic effects. Furthermore, the nature of the genotoxic effect was dependent on the concentration. Finally, we recommend that MN test and the comet assay should be included as sensitive endpoints in (eco)toxicological assays.

      PubDate: 2017-01-08T09:12:38Z
      DOI: 10.1016/j.plaphy.2016.12.026
      Issue No: Vol. 112 (2017)
       
  • Identification and expression analysis of the NAC transcription factor
           family in durum wheat (Triticum turgidum L. ssp. durum)
    • Authors: Mohammed Najib Saidi; Dhawya Mergby; Faiçal Brini
      Pages: 117 - 128
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Mohammed Najib Saidi, Dhawya Mergby, Faiçal Brini
      The NAC (NAM, ATAF and CUC) proteins belong to one of the largest plant-specific transcription factor (TF) families and play important roles in plant development processes, response to biotic and abiotic cues and hormone signaling. Our analysis led to the identification of 168 NAC genes in durum wheat, including nine putative membrane-bound TFs and 48 homeologous genes pairs. Phylogenetic analyses of TtNACs along with their Arabidopsis, grape, barley and rice counterparts divided these proteins into 8 phylogenetic groups and allowed the identification of TtNAC-A7, TtNAC-B35, TtNAC-A68, TtNAC-B69 and TtNAC-A43 as homologs of OsNAC1, OsNAC8, OsNTL2, OsNTL5 and ANAC025/NTL14, respectively. In silico expression analysis, using RNA-seq data, revealed tissue-specific and stress responsive TtNAC genes. The expression of ten selected genes was analyzed under salt and drought stresses in two contrasting tolerance cultivars. This analysis is the first report of NAC gene family in durum wheat and will be useful for the identification and selection of candidate genes associated with stress tolerance.

      PubDate: 2017-01-08T09:12:38Z
      DOI: 10.1016/j.plaphy.2016.12.028
      Issue No: Vol. 112 (2017)
       
  • Oil palm drought inducible DREB1 induced expression of DRE/CRT- and
           non-DRE/CRT-containing genes in lowland transgenic tomato under cold and
           PEG treatments
    • Authors: Azzreena Mohamad Azzeme; Siti Nor Akmar Abdullah; Maheran Abd Aziz; Puteri Edaroyati Megat Wahab
      Pages: 129 - 151
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Azzreena Mohamad Azzeme, Siti Nor Akmar Abdullah, Maheran Abd Aziz, Puteri Edaroyati Megat Wahab
      Dehydration-responsive element binding (DREB) transcription factor plays an important role in controlling the expression of abiotic stress responsive genes. An intronless oil palm EgDREB1 was isolated and confirmed to be a nuclear localized protein. Electrophoretic mobility shift and yeast one-hybrid assays validated its ability to interact with DRE/CRT motif. Its close evolutionary relation to the dicot NtDREB2 suggests a universal regulatory role. In order to determine its involvement in abiotic stress response, functional characterization was performed in oil palm seedlings subjected to different levels of drought severity and in EgDREB1 transgenic tomato seedlings treated by abiotic stresses. Its expression in roots and leaves was compared with several antioxidant genes using quantitative real-time PCR. Early accumulation of EgDREB1 in oil palm roots under mild drought suggests possible involvement in the initiation of signaling communication from root to shoot. Ectopic expression of EgDREB1 in T1 transgenic tomato seedlings enhanced expression of DRE/CRT and non-DRE/CRT containing genes, including tomato peroxidase (LePOD), ascorbate peroxidase (LeAPX), catalase (LeCAT), superoxide dismutase (LeSOD), glutathione reductase (LeGR), glutathione peroxidase (LeGP), heat shock protein 70 (LeHSP70), late embryogenesis abundant (LeLEA), metallothionine type 2 (LeMET2), delta 1-pyrroline-5- carboxylate synthetase (LePCS), ABA-aldehyde oxidase (LeAAO) and 9-cis- Epoxycarotenoid dioxygenase (LeECD) under PEG treatment and cold stress (4 °C). Altogether, these findings suggest that EgDREB1 is a functional regulator in enhancing tolerance to drought and cold stress.

      PubDate: 2017-01-08T09:12:38Z
      DOI: 10.1016/j.plaphy.2016.12.025
      Issue No: Vol. 112 (2017)
       
  • Antibacterial serine protease from Wrightia tinctoria: Purification and
           characterization
    • Authors: Sakthivel Muthu; Venkatesh Babu Gopal; Selvakumar Soundararajan; Karthikeyan Nattarayan; Karthik S. Narayan; Mythileeswari Lakshmikanthan; Sathuvan Malairaj; Palani Perumal
      Pages: 161 - 172
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Sakthivel Muthu, Venkatesh Babu Gopal, Selvakumar Soundararajan, Karthikeyan Nattarayan, Karthik S. Narayan, Mythileeswari Lakshmikanthan, Sathuvan Malairaj, Palani Perumal
      A serine protease was purified from the leaves of Wrightia tinctoria by sequential flow through method comprising screening, optimization, ammonium sulfate precipitation, gel filtration and ion exchange column chromatography. The yield and purification fold obtained were 11.58% and 9.56 respectively. A single band of serine protease was visualized on SDS-PAGE and 2-D gel electrophoretic analyses were revealed with the molecular mass of 38.5 kDa. Serine protease had an optimum pH of 8.0 and was stable at 45°C with high relative protease activity. The addition of metal ions such as Mg2+ and Mn2+ exhibits a high relative activity. Serine protease had a potent antibacterial activity against both Gram-positive and Gram-negative bacteria. A 10 μg/ml of serine protease was tested against S. aureus, M. luteus, P. aeruginosa and K. pneumoniae which had 21, 20, 18 and 17 mm of zone of inhibition respectively. Serine protease from W. tinctoria degrades the peptidoglycan layer of bacteria which was visualized by transmission electron microscopic analysis.
      Graphical abstract image

      PubDate: 2017-01-16T05:31:18Z
      DOI: 10.1016/j.plaphy.2017.01.003
      Issue No: Vol. 112 (2017)
       
  • Melatonin and resveratrol reverse the toxic effect of high boron (B) and
           modulate biochemical parameters in pepper plants (Capsicum annuum L.)
    • Authors: Eleana Sarafi; Pavlos Tsouvaltzis; Christos Chatzissavvidis; Anastasios Siomos; Ioannis Therios
      Pages: 173 - 182
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Eleana Sarafi, Pavlos Tsouvaltzis, Christos Chatzissavvidis, Anastasios Siomos, Ioannis Therios
      The objectives of this research were to test a possible involvement of melatonin (MEL) and resveratrol (RES) in restoring growth and to control boron (B) toxicity in peppers. The plants were subjected to four different nutrient solution treatments as following: 1) half-strength Hoagland's nutrient solution (Control), 2) half-strength Hoagland's nutrient solution+100 μM B (100 μMB), 3) half-strength Hoagland's nutrient solution+100 μM boron+100 μMresveratrol (100 μMRES), and 4) half-strength Hoagland's nutrient solution+100 μM B+1 μMmelatonin (1 μM MEL). Pepper plants subjected to B excess (100 μM) for 68 days (d) exhibited visible B toxicity symptoms, reduced rate of photosynthesis (Pn) and reduced dry weight (DW), while their leaf and fruit had the greatest increase of B concentration. The reduction of photosynthesis was restored, the reduction of DW was prevented, while the B leaf and fruit accumulation was moderated with the application of both 100 μMresveratrol (RES) and 1 μMmelatonin (MEL). Moreover, plants exposed to MEL and/or RES displayed no visible B toxicity symptoms. The present study revealed a novel role of MEL and/or RES in the adaptation of pepper plants to B excess based on plant growth, physiological and biochemical criteria.

      PubDate: 2017-01-16T05:31:18Z
      DOI: 10.1016/j.plaphy.2016.12.018
      Issue No: Vol. 112 (2017)
       
  • Sulphur alters chromium (VI) toxicity in Solanum melongena seedlings: Role
           of sulphur assimilation and sulphur-containing antioxidants
    • Authors: Madhulika Singh; Bishwajit Kumar Kushwaha; Samiksha Singh; Vipin Kumar; Vijay Pratap Singh; Sheo Mohan Prasad
      Pages: 183 - 192
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Madhulika Singh, Bishwajit Kumar Kushwaha, Samiksha Singh, Vipin Kumar, Vijay Pratap Singh, Sheo Mohan Prasad
      The present study investigates modulation in hexavalent chromium [Cr(VI) 25 μM] toxicity by sulphur (S; 0.5, 1.0 and 1.5 mM S as low (LS), medium (MS) and high sulphur (HS), respectively) in Solanum melongena (eggplant) seedlings. Biomass accumulation (fresh and dry weights), photosynthetic pigments, photosynthetic oxygen evolution and S content were declined by Cr(VI) toxicity. Furthermore, fluorescence characteristics (JIP-test) were also affected by Cr(VI), but Cr(VI) toxicity on photosystem II photochemistry was ameliorated by HS treatment via reducing damaging effect on PS II reaction centre and its reduction side. Enhanced respiration, Cr content and oxidative biomarkers: superoxide radical, hydrogen peroxide, lipid peroxidation and membrane damage were observed under Cr(VI) stress. Though Cr(VI) enhanced adenosine triphasphate sulfurylase (ATPS) and o-acetylserine(thiol)lyase (OASTL), glutathione-S-transferase (GST), glutathione reductase (GR) and ascorbate peroxidase (APX) activity, and content of total glutathione, cysteine and NP-SH, however, their levels/activity were further enhanced by S being maximum with HS treatment. The results show that Cr(VI) toxicity does increase under LS treatment while HS protected Cr(VI)-induced damaging effects in brinjal seedlings. Under HS treatment, in mitigating Cr(VI) toxicity, S assimilation and its associated metabolites such as cysteine, glutathione and NP-SH play crucial role.

      PubDate: 2017-01-16T05:31:18Z
      DOI: 10.1016/j.plaphy.2016.12.024
      Issue No: Vol. 112 (2017)
       
  • Magnesium and manganese affect photosynthesis, essential oil composition
           and phenolic compounds of Tanacetum parthenium
    • Authors: Soudeh Farzadfar; Fatemeh Zarinkamar; Mostafa Hojati
      Pages: 207 - 217
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Soudeh Farzadfar, Fatemeh Zarinkamar, Mostafa Hojati
      The accumulation of plant defense metabolites is closely associated with the concentration of nutrient elements, yet data related to the interactive effects of two nutrients on the deployment of phenolics and terpenoids are scare. In the present study, the interaction between magnesium (Mg) and manganese (Mn) on nutrient uptake, photosynthesis, oxidative status and the accumulation of phenolics and terpenoids in the leaves of feverfew plants grown at different concentrations of Mg and Mn was investigated. Nutrient uptake and photosynthesis were associated with the amount of applied Mg but could be modified by the concentration of Mn. Phenolic biosynthetic enzymes and individual phenolics were not only induced by Mg, but their levels were also dependent on the Mn supply. Additionally, the proportion of monoterpenes was enhanced by a deficiency of Mg rather than an excess of Mn. Deprivation of Mg also decreased the proportion of sesquiterpenes in the essential oil. Therefore, it appears that a high Mg and a low Mn supply lead to a marked shift from monoterpene to sesquiterpene production. Phenolic compounds also differentially accumulated under varying Mg and Mn concentrations. These results suggest a profound effect of the combined supply of Mg and Mn on the biosynthesis of terpenes and phenolics.

      PubDate: 2017-01-16T05:31:18Z
      DOI: 10.1016/j.plaphy.2017.01.002
      Issue No: Vol. 112 (2017)
       
  • Tomato SlGGP-LIKE gene participates in plant responses to chilling stress
           and pathogenic infection
    • Authors: Dong-Yue Yang; Meng Li; Na-Na Ma; Xing-Hong Yang; Qing-Wei Meng
      Pages: 218 - 226
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Dong-Yue Yang, Meng Li, Na-Na Ma, Xing-Hong Yang, Qing-Wei Meng
      Plants are always exposed to abiotic and biotic stresses which can adversely affect their growth and development. As an important antioxidant, AsA plays a vital role in plant defence against damage caused by stresses. In this study, we cloned a tomato GDP-L-galactose phosphorylase-like (SlGGP-LIKE) gene and investigated its role in resistance to abiotic and biotic stresses by using antisense transgenic (AS) tomato lines. The AsA content in AS plants was lower than that in WT plants. Under chilling stress, the growth of AS plants was inhibited significantly, and they yielded higher levels of ROS, REC and MDA but demonstrated weaker APX activity than that shown by WT plants. Additionally, the declined values of Pn, Fv/Fm, oxidisable P700, and D1 protein content of PSII in AS lines were significant. Furthermore, the effect on xanthophyll cycle of AS plants was more severe than that on WT plants, and the ratio of zeaxanthin (Z)/(V + A + Z) and (Z + 0.5 A)/(V + A + Z) in AS lines was lower than that in WT plants. In spite of chilling stress, under Pseudomonas syringae pv.tomato (Pst) DC3000 strain infection, AS plants showed lesser bacterial cell growth and dead cells than those shown by WT plants. This finding indicated that AS plants demonstrated stronger resistance against pathogenic infection. Results suggest that SlGGP-LIKE gene played an important role in plant defence against chilling stress and pathogenic infection.

      PubDate: 2017-01-16T05:31:18Z
      DOI: 10.1016/j.plaphy.2017.01.006
      Issue No: Vol. 112 (2017)
       
  • Functional characterization of a novel jasmonate ZIM-domain interactor
           (NINJA) from upland cotton (Gossypium hirsutum)
    • Authors: Le Wang; Shu-Ming Wu; Yue Zhu; Qiang Fan; Zhen-Nan Zhang; Guang Hu; Qing-Zhong Peng; Jia-He Wu
      Abstract: Publication date: Available online 4 January 2017
      Source:Plant Physiology and Biochemistry
      Author(s): Le Wang, Shu-Ming Wu, Yue Zhu, Qiang Fan, Zhen-Nan Zhang, Guang Hu, Qing-Zhong Peng, Jia-He Wu
      The jasmonic acid (JA) signalling pathway plays roles in plant development and defence against biotic and abiotic stresses. We isolated a cotton NINJA novel interactor of JA ZIM-domain) gene, designated GhNINJA, which contains a 1305 bp open read frame. The GhNINJA gene encodes a 434 amino acid peptide. According to quantitative real-time PCR analysis, GhNINJA is preferentially expressed in roots, and its expression level is greatly induced by Verticillium dahliae infection. Through a virus-induced gene silencing technique, we developed GhNINJA-silenced cotton plants, which had significantly decreased expression of the target gene with an average expression of 6% of the control. The regenerating lateral root growth of silenced plants was largely inhibited compared to the control. Analysis by microscopy demonstrated that the cell length of the root differentiation zone in GhNINJA-silenced plants is significantly shorter than those of the control. Moreover, the silenced plants exhibited higher tolerance to V. dahliae infection compared to the control, which was linked to the increased expression of the defence marker genes PDF1.2 and PR4. Together, these data indicated that knockdown of GhNINJA represses the root growth and enhances the tolerance to V. dahliae. Therefore, GhNINJA gene can be used as a candidate gene to breed the new cultivars for improving cotton yield and disease resistance.

      PubDate: 2017-01-08T09:12:38Z
      DOI: 10.1016/j.plaphy.2017.01.005
       
  • Sanguinarine-induced oxidative stress and apoptosis-like programmed cell
           death(AL-PCD) in root meristem cells of Allium cepa
    • Authors: Aneta Żabka; Konrad Winnicki; Justyna Teresa Polit; Janusz Maszewski
      Abstract: Publication date: Available online 4 January 2017
      Source:Plant Physiology and Biochemistry
      Author(s): Aneta Żabka, Konrad Winnicki, Justyna Teresa Polit, Janusz Maszewski
      A vast number of studies on plant cell systems clearly indicate that various biotic and abiotic stresses give rise to the uncontrolled increase in the level of reactive oxygen species (ROS). Excess concentrations of ROS result in damage to proteins, lipids, carbohydrates, and DNA, which may lead, in consequence, to the apoptotic cell death. The current study investigates the effects of sanguinarine (SAN), a natural alkaloid derived from the roots of Sanguinaria canadensis, on root apical meristem cells of Allium cepa. It is shown that SAN treatment generated large amounts of hydrogen peroxide (H2O2) and superoxide anion (O2·−). Oxidative stress induced in SAN-treated cells was correlated with DNA fragmentation, formation of micronuclei (MN), altered and ‘degenerated’ chromatin structures characteristic of apoptosis-like programmed cell death (AL-PCD). The experiments with SAN + MG132 (a proteasome inhibitor engaged in Topo II-mediated formation of cleavable complexes) and SAN + ascorbic acid (AA; H2O2 scavenger) seem to suggest, however, that the high level of H2O2 is not the only factor responsible for changes observed at the chromatin level and for the consequent cell death. Our findings imply that Topo II-DNA covalent complexes and 26S proteasomes are also involved in SAN-induced DNA damage.

      PubDate: 2017-01-08T09:12:38Z
      DOI: 10.1016/j.plaphy.2017.01.004
       
  • Peach leaf curl disease shifts sugar metabolism in severely infected
           leaves from source to sink
    • Authors: Stefano Moscatello; Simona Proietti; Roberto Buonaurio; Franco Famiani; Vittorio Raggi; Robert P. Walker; Alberto Battistelli
      Pages: 9 - 18
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Stefano Moscatello, Simona Proietti, Roberto Buonaurio, Franco Famiani, Vittorio Raggi, Robert P. Walker, Alberto Battistelli
      Peach leaf curl is a disease that affects the leaves of peach trees, and in severe cases all of the leaf can be similarly affected. This study investigated some effects of this disease on the metabolism of peach leaves in which all parts of the leaf were infected. These diseased leaves contained very little chlorophyll and performed little or no photosynthesis. Compared to uninfected leaves, diseased leaves possessed higher contents of fructose and especially glucose, but lowered contents of sucrose, sorbitol and especially starch. The activities of soluble acid invertase, neutral invertase, sorbitol dehydrogenase and sucrose synthase were all higher in diseased leaves, whereas, those of aldose-6-phosphate reductase and sucrose phosphate synthase were lower. The activities of hexokinase and fructokinase were little changed. In addition, immunblots showed that the contents of Rubisco and ADP-glucose phosphorylase were reduced in diseased leaves, whereas, the content of phosphoenolpyruvate carboxylase was increased. The results show that certain aspects of the metabolism of diseased leaves are similar to immature sink leaves. That is photosynthetic function is reduced, the leaf imports rather than exports sugars, and the contents of non-structural carbohydrates and enzymes involved in their metabolism are similar to sink leaves. Further, the effects of peach leaf curl on the metabolism of peach leaves are comparable to the effects of some other diseases on the metabolism of photosynthetic organs of other plant species.
      Graphical abstract image

      PubDate: 2016-12-23T03:51:50Z
      DOI: 10.1016/j.plaphy.2016.12.001
      Issue No: Vol. 112 (2016)
       
  • Implications of terminal oxidase function in regulation of salicylic acid
           on soybean seedling photosynthetic performance under water stress
    • Authors: Yanping Tang; Xin Sun; Tao Wen; Mingjie Liu; Mingyan Yang; Xuefei Chen
      Pages: 19 - 28
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Yanping Tang, Xin Sun, Tao Wen, Mingjie Liu, Mingyan Yang, Xuefei Chen
      The aim of this study is to investigate whether exogenous application of salicylic acid (SA) could modulate the photosynthetic capacity of soybean seedlings in water stress tolerance, and to clarify the potential functions of terminal oxidase (plastid terminal oxidase (PTOX) and alternative oxidase (AOX)) in SA′ s regulation on photosynthesis. The effects of SA and water stress on gas exchange, pigment contents, chlorophyll fluorescence, enzymes (guaiacol peroxidase (POD; EC 1.11.1.7), superoxide dismutase (SOD; EC 1.15.1.1), catalase (CAT; EC 1.11.1.6), ascorbate peroxidase (APX; EC 1.11.1.11) and NADP-malate dehydrogenase (NADP-MDH; EC1.1.1.82)) activity and transcript levels of PTOX, AOX1, AOX2a, AOX2b were examined in a hydroponic cultivation system. Results indicate that water stress significantly decreased the photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (E), pigment contents (Chla + b, Chla/b, Car), maximum quantum yield of PSⅡphotochemistry (Fv/Fm), efficiency of excitation capture of open PSⅡcenter (Fv’/Fm’), quantum efficiency of PSⅡphotochemistry (ΦPSⅡ), photochemical quenching (qP), and increased malondialdehyde (MDA) content and the activity of all the enzymes. SA pretreatment led to significant decreases in Ci and MDA content, and increases in Pn, Gs, E, pigment contents, Fv/Fm, Fv’/Fm’, ΦPSⅡ, qP, and the activity of all the enzymes. SA treatment and water stress alone significantly up-regulated the expression of PTOX, AOX1 and AOX2b. SA pretreatment further increased the transcript levels of PTOX and AOX2b of soybean seedling under water stress. These results indicate that SA application alleviates the water stress-induced decrease in photosynthesis may mainly through maintaining a lower reactive oxygen species (ROS) level, a greater PSⅡefficiency, and an enhanced alternative respiration and chlororespiration. PTOX and AOX may play important roles in SA-mediated resistance to water stress.

      PubDate: 2016-12-30T04:07:50Z
      DOI: 10.1016/j.plaphy.2016.11.016
      Issue No: Vol. 112 (2016)
       
  • Molecular cloning, characterization, heterologous expression and in-silico
           analysis of disordered boiling soluble stress-responsive wBsSRP protein
           from drought tolerant wheat cv.PBW 175
    • Authors: Gurmeen Rakhra; Tarandeep Kaur; Dhiraj Vyas; Arun Dev Sharma; Jatinder Singh; Gobind Ram
      Pages: 29 - 44
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Gurmeen Rakhra, Tarandeep Kaur, Dhiraj Vyas, Arun Dev Sharma, Jatinder Singh, Gobind Ram
      The structural and physico-chemical properties that account for the multi-functionality of dehydrins remain largely unknown. In this study, we identified, sequenced and cloned a stress regulated cDNA encoding a dehydrin-like boiling stable protein (designated as wBsSRP; wheat boiling stable stress responsive protein) from drought stressed seedlings of drought tolerant cultivar of wheat (PBW 175). qRT-PCR analysis documented high transcripts levels of wBsSRP during drought and cold conditions in the tolerant cv. PBW 175 as a part of adaptive response to stress while the levels were significantly lower in the sensitive cv. PBW 343. We also describe in-silico characterization and molecular modeling of wBsSRP through homology search, motif analysis, secondary structure prediction, active site prediction and 3D structure analysis. The physico-chemical properties and theoretical data of wBsSRP depicts that it is a canonical group 2 LEA protein. The recombinant wBsSRP protein when expressed in E. coli detected a specific differential band (∼11 kDa) on SDS- PAGE after IPTG induction. The functional analysis of wBsSRP in E. coli revealed that wBsSRP is essential for the survival of E. coli as well as for maintaining bacterial growth under various stress conditions. In vitro peroxidase protection assay during heat stress (50 and 100 °C) showed that in the presence of wBsSRP, peroxidase activity was significantly retained and/or increased. Based upon the findings, it is suggested that wBsSRP accentuated the effects of stress by acting as a protectant and by the stabilization of membranes, thereby contributing to the improved stress tolerance of the recombinant E. coli under various abiotic stress conditions. We suggest that these findings might provide the rationale for the mechanism of how these proteins obviate the adverse effects of dehydration stress.

      PubDate: 2016-12-30T04:07:50Z
      DOI: 10.1016/j.plaphy.2016.12.017
      Issue No: Vol. 112 (2016)
       
  • Differential phenolic production in leaves of Vitis vinifera cv. Alvarinho
           affected with esca disease
    • Authors: Marta R.M. Lima; Mafalda L. Felgueiras; Ana Cunha; Gisela Chicau; Federico Ferreres; Alberto C.P. Dias
      Pages: 45 - 52
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Marta R.M. Lima, Mafalda L. Felgueiras, Ana Cunha, Gisela Chicau, Federico Ferreres, Alberto C.P. Dias
      Esca is a destructive disease of complex etiology affecting grapevines worldwide. A major constraint to the study and control of esca is that the disease is not diagnosed until external leaf and/or fruit symptoms are visible; however external symptoms usually appear several years after infection onset. We studied the phenolic content of V. vinifera cv. Alvarinho leaves using high performance liquid chromatography-diode array detection-mass spectrometry (HPLC-DAD-MS)/LC-MS. Leaves from affected cordons with and without visible symptoms (diseased and apparently healthy leaves, respectively) and leaves from asymptomatic cordons (healthy leaves) were analyzed. Application of principal components analysis (PCA) to HPLC data showed a clear separation between diseased, apparently healthy, and healthy leaves, with the apparently healthy leaves clustered in a medial position. Several compounds were highly correlated with diseased leaves indicating a differential phenolic production due to esca disease in V. vinifera cv. Alvarinho leaves. Total phenolic production was shown to significantly increase in diseased leaves, compared to healthy leaves, with apparently healthy leaves containing a medial amount. Trans-caffeoyltartaric acid, trans-coumaroyl-tartaric acid, quercetin-3-O-glucoside, quercetin-3-O-galactoside, kaempferol-3-glucoside and myricetin were identified among the compounds associated with disease and their content shown to change similarly to total phenolic production. This study shows that it is possible to discriminate between diseased, healthy and apparently healthy leaves by applying PCA to HPLC data.
      Graphical abstract image

      PubDate: 2016-12-30T04:07:50Z
      DOI: 10.1016/j.plaphy.2016.12.020
      Issue No: Vol. 112 (2016)
       
  • Overexpression of a stress-responsive U-box protein gene VaPUB affects the
           accumulation of resistance related proteins in Vitis vinifera ‘Thompson
           Seedless’
    • Authors: Li Jiao; Yali Zhang; Jiang Lu
      Pages: 53 - 63
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Li Jiao, Yali Zhang, Jiang Lu
      Many U-box proteins have been identified and characterized as important factors against environmental stresses such as chilling, heat, salinity and pathogen attack in plant. Our previous research reported the cloning of a novel U-box protein gene VaPUB from Vitis amurensis ‘Zuoshanyi’ grape and suggested a function of it in related to cold stress in the model plant Arabidopsis system. In this study, the role of VaPUB in response to biotic and abiotic stress was further analyzed in the homologous grapevine system by studying the transcript regulation and the protein accumulation in VaPUB transgenic vines. The expression analysis assay shown that VaPUB was significantly up-regulated 6 h after cold treatment and as early as 2 h post inoculation with Plasmopara viticola, a pathogen causing downy mildew disease in grapevine. Over-expressing VaPUB in V. Vinifera ‘Thompson Seedless’ affected the microstructure of leaves. The proteome assay shown that the accumulation of pathogenesis-related protein PR10 and many proteins involved in carbon and energy metabolism, oxidation reaction and protein metabolism were significantly altered in transgenic vines. In comparison with wild type plants, the expression level of PR10 family genes was significantly decreased in VaPUB transgenic vines under P. viticola treatment or cold stress. Results from this study showed that the U-box protein gene PUB quickly responded to both biotic stress and abiotic stress and significantly influenced the accumulation of resistance related proteins in grapevine.

      PubDate: 2016-12-30T04:07:50Z
      DOI: 10.1016/j.plaphy.2016.12.019
      Issue No: Vol. 112 (2016)
       
  • Insights on germinability and desiccation tolerance in developing neem
           seeds (Azadirachta indica): Role of AOS, antioxidative enzymes and
           dehydrin-like protein
    • Authors: Balram Sahu; Alok Kumar Sahu; Srinivasa Rao Chennareddy; Avinash Soni; Subhash Chandra Naithani
      Pages: 64 - 73
      Abstract: Publication date: March 2017
      Source:Plant Physiology and Biochemistry, Volume 112
      Author(s): Balram Sahu, Alok Kumar Sahu, Srinivasa Rao Chennareddy, Avinash Soni, Subhash Chandra Naithani
      The germinability and desiccation tolerance (DT) in developing seed are regulated by cellular metabolism involving active oxygen species (AOS) and protective proteins during maturation drying. The aim of the present investigation was to unravel the functions of AOS (superoxide, H2O2 and OH-radical), antioxidative enzymes (SOD, CAT and APX) and dehydrin-like proteins in regulating the germinability and DT in undried and artificially desiccated developing neem seeds. Germination was first observed in seeds of 8 weeks after anthesis (waa) whereas DT was noticed from 9 waa. High levels of superoxide in undried and artificially desiccated seeds of 9 waa were rapidly declined up to 15 waa with simultaneous increase in levels of SOD (quantitative and isoenzymes) that dismutates superoxide with corresponding formation and accumulation of H2O2. Activities and isoenzymes of APX and CAT were promoted in seeds from 9 to 12 waa. Intensity of dehydrin-like proteins increased as development progressed in seeds with higher intensities in slow dried (SD) seeds. Desiccation modulated the metabolism for the acquisition of germinability and DT in the developing neem seeds from 8 to 15 waa by altering the levels of superoxide, H2O2 and OH-radical those possibly act as signalling molecules for reprogramming protective proteins. Desiccation mediated the expression of new bands of SOD and APX in undried as well as SD seeds during 9–12 waa but the bands were more intense in SD seeds. The superoxide and H2O2-regulated intensity of dehydrin-like protein in SD seeds further validated our conclusion.

      PubDate: 2016-12-30T04:07:50Z
      DOI: 10.1016/j.plaphy.2016.12.022
      Issue No: Vol. 112 (2016)
       
  • Map-based cloning and characterization of the novel yellow-green leaf gene
           ys83 in rice (Oryza sativa)
    • Authors: Xiaozhi Ma; Xiaoqiu Sun; Chunmei Li; Rui Huan; Changhui Sun; Yang Wang; Fuliang Xiao; Qian Wang; Purui Chen; Furong Ma; Kuan Zhang; Pingrong Wang; Xiaojian Deng
      Pages: 1 - 9
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Xiaozhi Ma, Xiaoqiu Sun, Chunmei Li, Rui Huan, Changhui Sun, Yang Wang, Fuliang Xiao, Qian Wang, Purui Chen, Furong Ma, Kuan Zhang, Pingrong Wang, Xiaojian Deng
      Leaf-color mutants have been extensively studied in rice, and many corresponding genes have been identified up to now. However, leaf-color mutation mechanisms are diverse and still need further research through identification of novel genes. In the present paper, we isolated a leaf-color mutant, ys83, in rice (Oryza sativa). The mutant displayed a yellow-green leaf phenotype at seedling stage, and then slowly turned into light-green leaf from late tillering stage. In its yellow leaves, photosynthetic pigment contents significantly decreased and the chloroplast development was retarded. The mutant phenotype was controlled by a recessive mutation in a nuclear gene on the short arm of rice chromosome 2. Map-based cloning and sequencing analysis suggested that the candidate gene was YS83 (LOC_Os02g05890) encoding a protein containing 165 amino acid residues. Gene YS83 was expressed in a wide range of tissues, and its encoded protein was targeted to the chloroplast. In the mutant, a T-to-A substitution occurred in coding sequence of gene YS83, which caused a premature translation of its encoded product. By introduction of the wild-type gene, the ys83 mutant recovered to normal green-leaf phenotype. Taken together, we successfully identified a novel yellow-green leaf gene YS83. In addition, number of productive panicles per plant and number of spikelets per panicle only reduced by 6.7% and 7.6%, respectively, meanwhile its seed setting rate and 1000-grain weight (seed size) were not significantly affected in the mutant, so leaf-color mutant gene ys83 could be used as a trait marker gene in commercial hybrid rice production.

      PubDate: 2016-11-24T13:41:53Z
      DOI: 10.1016/j.plaphy.2016.11.007
      Issue No: Vol. 111 (2016)
       
  • Ectopic expression of GA 2-oxidase 6 from rapeseed (Brassica napus L.)
           causes dwarfism, late flowering and enhanced chlorophyll accumulation in
           Arabidopsis thaliana
    • Authors: Jindong Yan; Xiaoying Liao; Reqing He; Ming Zhong; Panpan Feng; Xinmei Li; Dongying Tang; Xuanming Liu; Xiaoying Zhao
      Pages: 10 - 19
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Jindong Yan, Xiaoying Liao, Reqing He, Ming Zhong, Panpan Feng, Xinmei Li, Dongying Tang, Xuanming Liu, Xiaoying Zhao
      Gibberellins (GAs) are endogenous hormones that play an important role in higher plant growth and development. GA2-oxidase (GA2ox) promotes catabolism and inactivation of bioactive GAs or their precursors. In this study, we identified the GA2-oxidase gene, BnGA2ox6, and found it to be highly expressed in the silique and flower. Overexpression of BnGA2ox6 in Arabidopsis resulted in GA-deficiency symptoms, including inhibited elongation of the hypocotyl and stem, delayed seed germination, and late flowering. BnGA2ox6 overexpression reduced silique growth, but had no effect on seed development. Additionally, BnGA2ox6 overexpression enhanced chlorophyll b and total chlorophyll accumulation, and downregulated mRNA expression levels of the CHL1 and RCCR genes, which are involved in the chlorophyll degradation. These findings suggest that BnGA2ox6 regulates plant hight, silique development, flowering and chlorophyll accumulation in transgenic Arabidopsis.

      PubDate: 2016-11-24T13:41:53Z
      DOI: 10.1016/j.plaphy.2016.11.008
      Issue No: Vol. 111 (2016)
       
  • Identification of caleosin and oleosin in oil bodies of pine pollen
    • Authors: Buntora Pasaribu; Chii-Shiarng Chen; Yue Ken Liao; Pei-Luen Jiang; Jason T.C. Tzen
      Pages: 20 - 29
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Buntora Pasaribu, Chii-Shiarng Chen, Yue Ken Liao, Pei-Luen Jiang, Jason T.C. Tzen
      Unique proteins including steroleosin, caleosin, oleosin-L, and oleosin-G have been identified in seed oil bodies of pine (Pinus massoniana). In this study, mature pollen grains with wing-like bladders were collected from pine (Pinus elliottii). Ultrastructural studies showed that oil bodies were present in pollen grains, but not the attached bladders, and the presence of oil bodies was further confirmed by fluorescent staining with BODIPY 493/503. Stable oil bodies were successfully purified from pine pollen grains, and analyzed to be mainly composed of triacylglycerols. Putative oleosin and caleosin in pine pollen oil bodies were detected by immunoassaying with antibodies against sesame seed caleosin and lily pollen oleosin. Complete cDNA fragments encoding these two pollen oil-body proteins were obtained by PCR cloning. Sequence alignment showed that pine pollen caleosin (27 kDa) was highly homologous to pine seed caleosin (28 kDa) except for the lack of an appendix of eight residues at the C-terminus in accord with the 1 kDa difference in their molecular masses. Pine pollen oleosin (15 kDa) was highly homologous to pine seed oleosin-G (14 kDa) except for an insertion of eight residues at the N-terminus in accord with the 1 kDa difference in their molecular masses.

      PubDate: 2016-11-24T13:41:53Z
      DOI: 10.1016/j.plaphy.2016.11.010
      Issue No: Vol. 111 (2016)
       
  • UPLC-QTOF analysis reveals metabolomic changes in the flag leaf of wheat
           (Triticum aestivum L.) under low-nitrogen stress
    • Authors: Yang Zhang; Xin-ming Ma; Xiao-chun Wang; Ji-hong Liu; Bing-yan Huang; Xiao-yang Guo; Shu-ping Xiong; Gui-Xiao La
      Pages: 30 - 38
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Yang Zhang, Xin-ming Ma, Xiao-chun Wang, Ji-hong Liu, Bing-yan Huang, Xiao-yang Guo, Shu-ping Xiong, Gui-Xiao La
      Wheat is one of the most important grain crop plants worldwide. Nitrogen (N) is an essential macronutrient for the growth and development of wheat and exerts a marked influence on its metabolites. To investigate the influence of low nitrogen stress on various metabolites of the flag leaf of wheat (Triticum aestivum L.), a metabolomic analysis of two wheat cultivars under different induced nitrogen levels was conducted during two important growth periods based on large-scale untargeted metabolomic analysis using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF). Multivariate analyses—such as principle components analysis (PCA) and orthogonal partial least square discriminant analysis (OPLS-DA)—were used for data analysis. PCA yielded distinctive clustering information among the samples, classifying the wheat flag samples into two categories: those under normal N treatment and low N treatment. By processing OPLS-DA, eleven secondary metabolites were shown to be responsible for classifying the two groups. The secondary metabolites may be considered potential biomarkers of low nitrogen stress. Chemical analyses showed that most of the identified secondary metabolites were flavonoids and their related derivatives, such as iso-vitexin, iso-orientin and methylisoorientin-2″-O-rhamnoside, etc. This study confirmed the effect of low nitrogen stress on the metabolism of wheat, and revealed that the accumulation of secondary metabolites is a response to abiotic stresses. Meanwhile, we aimed to identify markers which could be used to monitor the nitrogen status of wheat crops, presumably to guide appropriate fertilization regimens. Furthermore, the UPLC-QTOF metabolic platform technology can be used to study metabolomic variations of wheat under abiotic stresses.
      Graphical abstract image

      PubDate: 2016-12-01T02:35:03Z
      DOI: 10.1016/j.plaphy.2016.11.009
      Issue No: Vol. 111 (2016)
       
  • cDNA-AFLP analysis of transcripts induced in chickpea plants by TiO2
           nanoparticles during cold stress
    • Authors: Saeed Amini; Reza Maali-Amiri; Rahmat Mohammadi; Seyyedeh-Sanam Kazemi- Shahandashti
      Pages: 39 - 49
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Saeed Amini, Reza Maali-Amiri, Rahmat Mohammadi, Seyyedeh-Sanam Kazemi- Shahandashti
      We evaluated the effect of TiO2 nanoparticles (NPs) on cold tolerance (CT) development in two chickpea (Cicer arietinum L.) genotypes (Sel96Th11439, cold tolerant, and ILC533, cold susceptible) by using cDNA-amplified fragment length polymorphism (cDNA-AFLP) technique during the first and sixth days of cold stress (CS) at 4 °C. Selective amplification by primer combinations generated 4200 transcript-derived fragments (TDFs) while 100 of them (2.62%) were differentially expressed. During CS, 60 differentially expressed TDFs of TiO2 NPs-treated plants were cloned and 10 of them produced successfully readable sequences. These data represented different groups of genes involved in metabolism pathways, cellular defense, cell connections and signaling, transcriptional regulation and chromatin architecture. Two out of 10 TDFs were unknown genes with uncharacterized functions or sequences without homology to known ones. The network-based analysis showed a gene-gene relationship in response to CS. Quantitative reverse-transcriptase polymerase chain reaction (qPCR) confirmed differential expression of identified genes (six out of 10 TDFs) with potential functions in CT and showed similar patterns with cDNA-AFLP results. An increase in transcription level of these TDFs, particularly on the first day of CS, was crucial for developing CT through decreasing electrolyte leakage index (ELI) content in tolerant plants compared to susceptible ones, as well as in TiO2 NPs-treated plants compared to control ones. It could also indicate probable role of TiO2 NPs against CS-induced oxidative stress. Therefore, a new application of TiO2 NPs in CT development is suggested for preventing or controlling the damages in field conditions and increasing crop productivity.

      PubDate: 2016-12-01T02:35:03Z
      DOI: 10.1016/j.plaphy.2016.11.011
      Issue No: Vol. 111 (2016)
       
  • Characterization and fine-mapping of a novel premature leaf senescence
           mutant yellow leaf and dwarf 1 in rice
    • Authors: Luchang Deng; Peng Qin; Zhi Liu; Geling Wang; Weilan Chen; Jianhua Tong; Langtao Xiao; Bin Tu; Yuantao Sun; Wei Yan; Hang He; Jun Tan; Xuewei Chen; Yuping Wang; Shigui Li; Bingtian Ma
      Pages: 50 - 58
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Luchang Deng, Peng Qin, Zhi Liu, Geling Wang, Weilan Chen, Jianhua Tong, Langtao Xiao, Bin Tu, Yuantao Sun, Wei Yan, Hang He, Jun Tan, Xuewei Chen, Yuping Wang, Shigui Li, Bingtian Ma
      Leaves are the main organs in which photosynthates are produced. Leaf senescence facilitates the translocation of photosynthates and nutrients from source to sink, which is important for plant development and especially for crop yield. However, the molecular mechanism of leaf senescence is unknown. Here, we identified a mutant, yellow leaf and dwarf 1 (yld1), which exhibited decreased plant height and premature leaf senescence. Nitroblue tetrazolium and diamiobenzidine staining analyses revealed that the concentrations of reactive oxygen species were higher in yld1 leaves than in wild type leaves. The photosynthetic pigment contents were significantly decreased in yld1. The yld1 chloroplasts had collapsed and were filled with abnormal starch granules. Combining bulk segregant and MutMap gene mapping approaches, the mutation responsible for the yld1 phenotype was mapped to a 7.3 Mb centromeric region, and three non-synonymous single nucleotide polymorphisms located in three novel genes were identified in this region. The expression patterns of the three candidate genes indicated that LOC_Os06g29380 had the most potential for functional verification. Plant hormone measurements showed that salicylic acid was highly accumulated in yld1 leaves when compared with wild type leaves, and yld1 was more sensitive to salicylic acid than wild type. This work lays the foundation for understanding the molecular regulatory mechanism of leaf senescence, and may reveal new connections among the molecular pathways related to leaf senescence, starch metabolism and salicylic acid signaling.

      PubDate: 2016-12-01T02:35:03Z
      DOI: 10.1016/j.plaphy.2016.11.012
      Issue No: Vol. 111 (2016)
       
  • Biochemical precursor effects on the fatty acid production in cell
           suspension cultures of Theobroma cacao L.
    • Authors: O. Parra; A.M. Gallego; A. Urrea; L.F. Rojas; C. Correa; L. Atehortúa
      Pages: 59 - 66
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): O. Parra, A.M. Gallego, A. Urrea, L.F. Rojas, C. Correa, L. Atehortúa
      Cocoa butter (CB) is composed of 96% palmitic, stearic, oleic, linoleic and linolenic fatty acids that are responsible for the hardness, texture and fusion properties of chocolate. Through in vitro plant cell culture it is possible to modify CB lipid profiles and to study the fatty acid biosynthesis pathway on a subcellular level, evaluating fundamental aspects to enhance in vitro fatty acid production in a specific and controlled way. In this research, culture media was supplemented with acetate, biotin, pyruvate, bicarbonate and glycerol at three different concentrations and the effects on the biomass production (g/L), cell viability, and fatty acids profile and production was evaluated in in vitro cell suspensions culture. It was found that biotin stimulated fatty acid synthesis without altering cell viability and cell growth. It was also evident a change in the lipid profile of cell suspensions, increasing middle and long chain fatty acids proportion, which are unusual to those reported in seeds; thus implying that it is possible to modify lipid profiles according to the treatment used. According to the results of sucrose gradients and enzyme assays performed, it is proposed that cacao cells probably use the pentose phosphate pathway, mitochondria being the key organelle in the carbon flux for the synthesis of reductant power and fatty acid precursors.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.11.013
      Issue No: Vol. 111 (2016)
       
  • Functional regulation of ginsenoside biosynthesis by RNA interferences of
           a UDP-glycosyltransferase gene in Panax ginseng and Panax quinquefolius
    • Authors: Chao Lu; Shoujing Zhao; Guanning Wei; Huijuan Zhao; Qingling Qu
      Pages: 67 - 76
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Chao Lu, Shoujing Zhao, Guanning Wei, Huijuan Zhao, Qingling Qu
      Panax ginseng (Asian ginseng) and Panax quinquefolius (American ginseng) have been used as medicinal and functional herbal remedies worldwide. Different properties of P. ginseng and P. quinquefolius were confirmed not only in clinical findings, but also at cellular and molecular levels. The major pharmacological ingredients of P. ginseng and P. quinquefolius are the triterpene saponins known as ginsenosides. The P. ginseng roots contain a higher ratio of ginsenoside Rg1:Rb1 than that in P. quinquefolius. In ginseng plants, various ginsenosides are synthesized via three key reactions: cyclization, hydroxylation and glycosylation. To date, several genes including dammarenediol synthase (DS), protopanaxadiol synthase and protopanaxatriol synthase have been isolated in P. ginseng and P. quinquefolius. Although some glycosyltransferase genes have been isolated and identified association with ginsenoside synthesis in P. ginseng, little is known about the glycosylation mechanism in P. quinquefolius. In this paper, we cloned and identified a UDP-glycosyltransferase gene named Pq3-O-UGT2 from P. quinquefolius (GenBank accession No. KR106207). In vitro enzymatic activity experiments biochemically confirmed that Pq3-O-UGT2 catalyzed the glycosylation of Rh2 and F2 to produce Rg3 and Rd, and the chemical structure of the products were confirmed susing high performance liquid chromatography electrospray ionization mass spectrometry (HPLC/ESI-MS). High sequence similarity between Pq3-O-UGT2 and PgUGT94Q2 indicated a close evolutionary relationship between P. ginseng and P. quinquefolius. Moreover, we established both P. ginseng and P. quinquefolius RNAi transgenic roots lines. RNA interference of Pq3-O-UGT2 and PgUGT94Q2 led to reduce levels of ginsenoside Rd, protopanaxadiol-type and total ginsenosides. Expression of key genes including protopanaxadiol and protopanaxatriol synthases was up-regulated in RNAi lines, while expression of dammarenediol synthase gene was not obviously increased. These results revealed that P. quinquefolius was more sensitive to the RNAi of Pq3-O-UGT2 and PgUGT94Q2 when compared with P. ginseng.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.11.017
      Issue No: Vol. 111 (2016)
       
  • Distinct cold responsiveness of a StInvInh2 gene promoter in transgenic
           potato tubers with contrasting resistance to cold-induced sweetening
    • Authors: Xun Liu; Weiling Shi; Wang Yin; Jichun Wang
      Pages: 77 - 84
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Xun Liu, Weiling Shi, Wang Yin, Jichun Wang
      Potato (Solanum tuberosum L.) vacuolar invertase (β-fructofuranosidase; EC 3.2.1.26) inhibitor 2 (StInvInh2) plays an important role in cold-induced sweetening (CIS) of potato tubers. The transcript levels of StInvInh2 were increased by prolonged cold in potato tubers with CIS-resistance but decreased in potato tubers with CIS-sensitivity. However, the transcript regulation mechanisms of StInvInh2 responding to prolonged cold are largely unclear in CIS-resistant and CIS-sensitive genotypes. In the present study, the 5′-flanking sequence of the StInvInh2 was cloned, and cis-acting elements were predicted. No informative differences in StInvInh2 promoter structure between resistant and sensitive-CIS potato genotypes were observed. Histochemical assay showed that the promoter of StInvInh2 mainly governed β-glucuronidase (GUS) expression in potato microtubers. Quantitative analysis of GUS expression suggested that StInvInh2 promoter activity was enhanced by prolonged cold in CIS-resistant genotype tubers but suppressed in CIS-sensitive tubers. These findings provide essential information regarding transcriptional regulatory mechanisms of StInvInh2 in cold-stored tubers contrasting CIS capacity.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.11.021
      Issue No: Vol. 111 (2016)
       
  • Mining, identification and function analysis of microRNAs and target genes
           in peanut (Arachis hypogaea L.)
    • Authors: Tingting Zhang; Shuhao Hu; Caixia Yan; Chunjuan Li; Xiaobo Zhao; Shubo Wan; Shihua Shan
      Pages: 85 - 96
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Tingting Zhang, Shuhao Hu, Caixia Yan, Chunjuan Li, Xiaobo Zhao, Shubo Wan, Shihua Shan
      In the present investigation, a total of 60 conserved peanut (Arachis hypogaea L.) microRNA (miRNA) sequences, belonging to 16 families, were identified using bioinformatics methods. There were 392 target gene sequences, identified from 58 miRNAs with Target-align software and BLASTx analyses. Gene Ontology (GO) functional analysis suggested that these target genes were involved in mediating peanut growth and development, signal transduction and stress resistance. There were 55 miRNA sequences, verified employing a poly (A) tailing test, with a success rate of up to 91.67%. Twenty peanut target gene sequences were randomly selected, and the 5′ rapid amplification of the cDNA ends (5′-RACE) method were used to validate the cleavage sites of these target genes. Of these, 14 (70%) peanut miRNA targets were verified by means of gel electrophoresis, cloning and sequencing. Furthermore, functional analysis and homologous sequence retrieval were conducted for target gene sequences, and 26 target genes were chosen as the objects for stress resistance experimental study. Real-time fluorescence quantitative PCR (qRT-PCR) technology was applied to measure the expression level of resistance-associated miRNAs and their target genes in peanut exposed to Aspergillus flavus (A. flavus) infection and drought stress, respectively. In consequence, 5 groups of miRNAs & targets were found accorded with the mode of miRNA negatively controlling the expression of target genes. This study, preliminarily determined the biological functions of some resistance-associated miRNAs and their target genes in peanut.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.11.018
      Issue No: Vol. 111 (2016)
       
  • Identification and subcellular localization analysis of two rubber
           elongation factor isoforms on Hevea brasiliensis rubber particles
    • Authors: Longjun Dai; Zhiyi Nie; Guijuan Kang; Yu Li; Rizhong Zeng
      Pages: 97 - 106
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Longjun Dai, Zhiyi Nie, Guijuan Kang, Yu Li, Rizhong Zeng
      Rubber elongation factor (REF) is the most abundant protein found on the rubber particles or latex from Hevea brasiliensis (the Para rubber tree) and is considered to play important roles in natural rubber (cis-polyisoprene) biosynthesis. 16 BAC (benzyldimethyl-n-hexadecylammonium chloride)/SDS-PAGE separations and mass spectrometric identification had revealed that two REF isoforms shared similar amino acid sequences and common C-terminal sequences. In this study, the gene sequences encoding these two REF isoforms (one is 23.6 kDa in size with 222 amino acid residues and the other is 27.3 kDa in size with 258 amino acid residues) were obtained. Their proteins were relatively enriched by sequential extraction of the rubber particle proteins and separated by 16 BAC/SDS-PAGE. The localization of these isoforms on the surfaces of rubber particles was further verified by western blotting and immunogold electron microscopy, which demonstrated that these two REF isoforms are mainly located on the surfaces of larger rubber particles and that they bind more tightly to rubber particles than the most abundant REF and SRPP (small rubber particle protein).

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.11.006
      Issue No: Vol. 111 (2016)
       
  • Dark-chilling induces substantial structural changes and modifies
           galactolipid and carotenoid composition during chloroplast biogenesis in
           cucumber (Cucumis sativus L.) cotyledons
    • Authors: Joanna Skupień; Joanna Wójtowicz; Łucja Kowalewska; Radosław Mazur; Maciej Garstka; Katarzyna Gieczewska; Agnieszka Mostowska
      Pages: 107 - 118
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Joanna Skupień, Joanna Wójtowicz, Łucja Kowalewska, Radosław Mazur, Maciej Garstka, Katarzyna Gieczewska, Agnieszka Mostowska
      Plants in a temperate climate are often subject to different environmental factors, chilling stress among them, which influence the growth especially during early stages of plant development. Chloroplasts are one of the first organelles affected by the chilling stress. Therefore the proper biogenesis of chloroplasts in early stages of plant growth is crucial for undertaking the photosynthetic activity. In this paper, the analysis of the cotyledon chloroplast biogenesis at different levels of plastid organization was performed in cucumber, one of the most popular chilling sensitive crops. Influence of low temperature on the ultrastructure was manifested by partial recrystallization of the prolamellar body, the formation of elongated grana thylakoids and a change of the prolamellar body structure from the compacted “closed” type to a more loose “open” type. Structural changes are strongly correlated with galactolipid and carotenoid content. Substantial changes in the galactolipid and the carotenoid composition in dark-chilled plants, especially a decrease of the monogalactosyldiacylglycerol to digalactosyldiacylglycerol ratio (MGDG/DGDG) and an increased level of lutein, responsible for a decrease in membrane fluidity, were registered together with a slower adaptation to higher light intensity and an increased level of non-photochemical reactions. Changes in the grana thylakoid fluidity, of their structure and photosynthetic efficiency in developing chloroplasts of dark-chilled plants, without significant changes in the PSI/PSII ratio, could distort the balance of photosystem rearrangements and be one of the reasons of cucumber sensitivity to chilling.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.11.022
      Issue No: Vol. 111 (2016)
       
  • Effect of prolonged water stress on essential oil content, compositions
           and gene expression patterns of mono- and sesquiterpene synthesis in two
           oregano (Origanum vulgare L.) subspecies
    • Authors: Mohammad Reza Morshedloo; Lyle E. Craker; Alireza Salami; Vahideh Nazeri; Hyunkyu Sang; Filippo Maggi
      Pages: 119 - 128
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Mohammad Reza Morshedloo, Lyle E. Craker, Alireza Salami, Vahideh Nazeri, Hyunkyu Sang, Filippo Maggi
      Origanum vulgare L., recognized throughout the world as a popular medicinal and flavoring herb, contains a wide array of medicinally active components, including phenolic glucosides, flavonoids, tannins, sterols and high amounts of terpenoids. Especially the latter are often extracted by hydrodistillation resulting in the so-called essential oil that is rich in monoterpenes (e.g. carvacrol, thymol, linalyl acetate) and/or sesquiterpenes (e.g. (E)-β-caryophyllene, germacrene D, bicyclogermacrene, β-caryophyllene oxide). Water stresses in the arid and semiarid regions of the world severely affect growth and productivity of oregano. To determine the variation in essential oil and gene expression pathway of Iranian oregano under prolonged water stress, two native subspecies of O. vulgare (subsp. virens and subsp. gracile) were studied. The plants, grown in pots, were subjected to three water stress conditions, i.e. no stress, mild stress (60± 5% FMC) and moderate stress (40± 5% FMC). The studied subspecies exhibited significant differences in essential oil content, compositions, and patterns of gene expression under water stress conditions. The essential oil of O. vulgare subsp. gracile was rich in the phenolic monoterpene carvacrol (46.86–52.07%), whereas the sesquiterpene hydrocarbon (Z)-α-bisabolene (39.17–42.64%) was the major constituent in the oil of O. vulgare subsp. virens. Both the mild and moderate water stresses significantly increased the essential oil content of O. vulgare subsp. gracile, but did not significantly change the essential oil content of O. vulgare subsp. virens nor the level of carvacrol and (Z)-α-bisabolene in the investigated subspecies. Interestingly, the amount of (E)-β-caryophyllene in O. vulgare subsp. virens was significantly increased under water stress conditions. Gene expression studies supported the above findings and demonstrated that there are two different pathways affecting the biosynthesis of the terpenoid precursors geranyl pyrophosphate (GPP) and farnesyl pyrophosphate (FPP). In O. vulgare subsp. gracile, HMGR, Ovtps2 and CYP71D180 transcript were up-regulated under mild and moderate water stress conditions. Transcription of FPPS was apparently down-regulated in water-stressed O. vulgare subsp. gracile. Investigation of terpene synthases expression levels in oregano subspecies demonstrated that Ovtps2 and Ovtps6 controlled the concentration of carvacrol and (E)-β-caryophyllene in oregano essential oils, respectively.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.11.023
      Issue No: Vol. 111 (2016)
       
  • Molecular and physiological responses of Iranian Perennial ryegrass as
           affected by Trinexapac ethyl, Paclobutrazol and Abscisic acid under
           drought stress
    • Authors: Mohammad Hossein Sheikh Mohammadi; Nematollah Etemadi; Mohammad Mehdi Arab; Mostafa Aalifar; Mostafa Arab; Mohammad Pessarakli
      Pages: 129 - 143
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Mohammad Hossein Sheikh Mohammadi, Nematollah Etemadi, Mohammad Mehdi Arab, Mostafa Aalifar, Mostafa Arab, Mohammad Pessarakli
      Drought stress is the major limiting factor which affects turfgrass management in area with restricted rainfall or irrigation water supply. Trinexapac ethyl (TE), Paclobutrazol (PAC) and Abscisic acid (ABA) are three plant growth regulators (PGRs) that are commonly used on turf species for increasing their tolerance to different environmental stresses such as drought. However, little is known about the impact of PGRs on stress tolerance of Iranian Perennial ryegrass (Lolium perenne). The present study was conducted to examine the visual and physiological changes of Iranian Perennial ryegrass in response to foliar application of TE, PAC, and ABA under drought stress conditions. According to the obtained results, application of all three PGRs considerably restored visual quality of drought exposed plants. TE treatment increased chlorophyll content, proline content and resulted in less malondialdehyde (MDA) in drought stressed Perennial ryegrass. Application of all PGRs enhanced the relative water content (RWC) and decreased the electrolyte leakage (EL) and Hydrogen peroxide contents (H2O2 content) of plants under drought stress, though the impact of TE was more pronounced. Throughout the experiment, TE- and ABA-treated plant showed greater soluble sugar (SSC) content as compared to the control. Antioxidant enzymes activities of drought exposed plants were considerably increased by PGRs application. Catalase (CAT) and Superoxide dismutase (SOD) activities were greater in TE-treated grasses followed by PAC-treated plants. Ascorbate peroxidase (APX) and peroxidase (POD) activities were significantly enhanced by TE and ABA application. The results of the present investigation suggest that application of TE, ABA and PAC enhances drought tolerance in Perennial ryegrass. TE, PAC and ABA were all effective in mitigating physiological damages resulting from drought stress, however the beneficial effects of TE were more pronounced. The result obtained of real time-PCR suggested that regulation of CAT, APX, POD and SOD genes expression at translational levels highly depended on the application of TE, PAC and ABA. Also, the results showed that deletion mutation in SOD and POD genes were not leading to enzyme inactivation.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.11.014
      Issue No: Vol. 111 (2016)
       
  • Arsenic affects the production of glucosinolate, thiol and phytochemical
           compounds: A comparison of two Brassica cultivars
    • Authors: Chandana Pandey; Rehna Augustine; Medha Panthri; Ismat Zia; Naveen C. Bisht; Meetu Gupta
      Pages: 144 - 154
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Chandana Pandey, Rehna Augustine, Medha Panthri, Ismat Zia, Naveen C. Bisht, Meetu Gupta
      Arsenic (As), a non-essential metalloid, severely affects the normal functioning of plants, animals and humans. Plants play a crucial role in metabolic, physiological and numerous detoxification mechanisms to cope up with As induced stress. This study aimed to examine the differential response in two Brassica juncea cultivars, Varuna and Pusa Jagannath (PJn) exposed to different doses of As (50, 150, 300 μM) for 48 h duration. Change in morphological traits, concentration of individual as well as total GSL, sulfur related thiol proteins, sulfur content, and phytochemicals were analyzed in both cultivars. Accumulation pattern of As showed dose dependent accumulation in both the cultivars, being more in PJn. Our finding revealed that both cultivars were tolerant at low concentrations of As, while at higher concentration Varuna excelled over PJn. The increased tolerance of Varuna cultivar exposed to 150 and 300 μM concentration of As, correlated with its increased thiol related proteins, sulfur content and phytochemicals, which serves as defence strategy in the plant against oxidative stress. Differential pattern of total as well as individual GSLs content was observed in both Varuna and PJn cultivars. Varuna cultivar showed higher level of total and aliphatic GSLs, which serves as defence compound with other detoxification machineries to combat As stress. Our findings provide foundation for developing metalloid tolerant crops by analyzing the role of different genes involved in GSL mechanism and signaling pathways in different organs of plant.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.11.026
      Issue No: Vol. 111 (2016)
       
  • Identification of lipopolysaccharide-interacting plasma membrane-type
           proteins in Arabidopsis thaliana
    • Authors: Cornelius S. Vilakazi; Ian A. Dubery; Lizelle A. Piater
      Pages: 155 - 165
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Cornelius S. Vilakazi, Ian A. Dubery, Lizelle A. Piater
      Lipopolysaccharide (LPS) is an amphiphatic bacterial glycoconjugate found on the external membrane of Gram-negative bacteria. This endotoxin is considered as a microbe-associated molecular pattern (MAMP) molecule and has been shown to elicit defense responses in plants. Here, LPS-interacting proteins from Arabidopsis thaliana plasma membrane (PM)-type fractions were captured and identified in order to investigate those involved in LPS perception and linked to triggering of innate immune responses. A novel proteomics-based affinity-capture strategy coupled to liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed for the enrichment and identification of LPS-interacting proteins. As such, LPS isolated from Burkholderia cepacia (LPS B.cep. ) was immobilized on three independent and distinct affinity-based matrices to serve as bait for interacting proteins from A. thaliana leaf and callus tissue. These were resolved by 1D electrophoresis and identified by mass spectrometry. Proteins specifically bound to LPS B.cep. have been implicated in membrane structure (e.g. COBRA-like and tubulin proteins), membrane trafficking and/or transport (e.g. soluble NSF attachment protein receptor (SNARE) proteins, patellin, aquaporin, PM instrinsic proteins (PIP) and H+-ATPase), signal transduction (receptor-like kinases and calcium-dependent protein kinases) as well as defense/stress responses (e.g. hypersensitive-induced response (HIR) proteins, jacalin-like lectin domain-containing protein and myrosinase-binding proteins). The novel affinity-capture strategy for the enrichment of LPS-interacting proteins proved to be effective, especially in the binding of proteins involved in plant defense responses, and can thus be used to elucidate LPS-mediated molecular recognition and disease mechanism(s).

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.11.025
      Issue No: Vol. 111 (2016)
       
  • Nitric oxide protects carbon assimilation process of watermelon from
           boron-induced oxidative injury
    • Authors: Mohamed Farag; Ullah Najeeb; Jinghua Yang; Zhongyuan Hu; Zhang Ming Fang
      Pages: 166 - 173
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Mohamed Farag, Ullah Najeeb, Jinghua Yang, Zhongyuan Hu, Zhang Ming Fang
      Nitric oxide (NO) mediates plant response to a variety of abiotic stresses; however, limited information is available on its effect on boron (B)-stressed watermelon plants. The present study investigates the mechanism through which NO protects watermelon seedlings from B deficiency and toxicity stresses. Five days old watermelon seedlings were exposed to B (0, 0.5 and 10 mg L−1) alone or with 75 μmole of NO donor sodium nitroprusside (SNP) for 30 days. Both low and high B concentrations in the media altered nutrient accumulation and impaired various physiological processes of watermelon seedlings, leading to a significant reduction in biomass production. The plants exposed to B deficient or toxic concentrations had 66 and 69% lower shoot dry weight, respectively compared with optimum B levels. B toxicity-induced growth inhibition of watermelon seedlings was associated with high B translocation to shoot tissues, which caused lipid membrane peroxidation (12% increase) and chlorophyll destruction (25% reduction). In contrast, B deficiency accelerated generation of reactive oxygen species (ROS), specifically OH−1 and induced cellular oxidative injury. Exogenously applied SNP promoted leaf chlorophyll, photosynthesis and consequently biomass production in B-stressed watermelon seedlings by reducing B accumulation, lipid membrane peroxidation and ROS generation. It also activated antioxidant enzymes such as SOD, POD and APX, and protected the seedlings from ROS-induced cellular burst.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.11.024
      Issue No: Vol. 111 (2016)
       
  • Transcription activation activity of ERD15 protein from Morus indica
    • Authors: Bushra Saeed; Paramjit Khurana
      Pages: 174 - 178
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Bushra Saeed, Paramjit Khurana
      Early Responsive to Dehydration (ERD) genes are described as rapid response mediators of dehydration stress. Recently, ERD15 has emerged as a novel stress induced transcription factor which might be involved in mediating distinct stress responses in plants. In order to determine whether mulberry ERD15 can act as functional transcription factor, yeast-based assays were performed. Mulberry ERD15 was found to drive high level reporter gene expression in yeast which suggests it may function as a transcription factor. However, due to lack of an identifiable DNA binding domain, deletion analysis was carried out to determine the putative region of the protein involved in mediating protein-DNA interaction. Our results indicate that the region between 70 and 100 amino acids is critical in conferring transcription activation activity and might harbor the DNA binding region of ERD15.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.11.020
      Issue No: Vol. 111 (2016)
       
  • Hydrogen sulfide alleviates mercury toxicity by sequestering it in roots
           or regulating reactive oxygen species productions in rice seedlings
    • Authors: Zhen Chen; Moshun Chen; Ming Jiang
      Pages: 179 - 192
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Zhen Chen, Moshun Chen, Ming Jiang
      Soil mercury (Hg) contamination is a major factor that affects agricultural yield and food security. Hydrogen sulfide (H2S) plays multifunctional roles in mediating a variety of responses to abiotic stresses. The effects of exogenous H2S on rice (Oryza sativa var ‘Nipponbare’) growth and metabolism under mercuric chloride (HgCl2) stress were investigated in this study. Either 100 or 200 μM sodium hydrosulfide (NaHS, a donor of H2S) pretreatment improved the transcription of bZIP60, a membrane-associated transcription factor, and then enhanced the expressions of non-protein thiols (NPT) and metallothioneins (OsMT-1) to sequester Hg in roots and thus inhibit Hg transport to shoots. Meanwhile, H2S promoted seedlings growth significantly even in the presences of Hg and superoxide dismutase (SOD, EC 1.15.1.1) or catalase (CAT, EC 1.11.1.6) inhibitors, diethyldithiocarbamate (DDC) or 3-amino-1,2,4-triazole (AT). H2S might act as an antioxidant to inhibit or scavenge reactive oxygen species (ROS) productions for maintaining the lower MDA and H2O2 levels, and thereby preventing oxidative damages. All these results indicated H2S effectively alleviated Hg toxicity by sequestering it in roots or by regulating ROS in seedlings and then thus significantly promoted rice growth.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.11.027
      Issue No: Vol. 111 (2016)
       
  • Zinc and selenium accumulation and their effect on iron bioavailability in
           common bean seeds
    • Authors: Marislaine A. de Figueiredo; Paulo F. Boldrin; Jonathan J. Hart; Messias J.B. de Andrade; Luiz R.G. Guilherme; Raymond P. Glahn; Li Li
      Pages: 193 - 202
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Marislaine A. de Figueiredo, Paulo F. Boldrin, Jonathan J. Hart, Messias J.B. de Andrade, Luiz R.G. Guilherme, Raymond P. Glahn, Li Li
      Common beans (Phaseolus vulgaris) are the most important legume crops. They represent a major source of micronutrients and a target for essential trace mineral enhancement (i.e. biofortification). To investigate mineral accumulation during seed maturation and to examine whether it is possible to biofortify seeds with multi-micronutrients without affecting mineral bioavailability, three common bean cultivars were treated independently with zinc (Zn) and selenium (Se), the two critical micronutrients that can be effectively enhanced via fertilization. The seed mineral concentrations during seed maturation and the seed Fe bioavailability were analyzed. Common bean seeds were found to respond positively to Zn and Se treatments in accumulating these micronutrients. While the seed pods showed a decrease in Zn and Se along with Fe content during pod development, the seeds maintained relatively constant mineral concentrations during seed maturation. Selenium treatment had minimal effect on the seed accumulation of phytic acid and polyphenols, the compounds affecting Fe bioavailability. Zinc treatment reduced phytic acid level, but did not dramatically affect the concentrations of total polyphenols. Iron bioavailability was found not to be greatly affected in seeds biofortified with Se and Zn. In contrast, the inhibitory polyphenol compounds in the black bean profoundly reduced Fe bioavailability. These results provide valuable information for Se and Zn enhancement in common bean seeds and suggest the possibility to biofortify with these essential nutrients without greatly affecting mineral bioavailability to increase the food quality of common bean seeds.

      PubDate: 2016-12-15T03:38:49Z
      DOI: 10.1016/j.plaphy.2016.11.019
      Issue No: Vol. 111 (2016)
       
  • Biochemical and physiological changes during fruit development and
           ripening of two sweet cherry varieties with different levels of cracking
           tolerance
    • Authors: Jordi Giné-Bordonaba; Gemma Echeverria; Dolors Ubach; Ingrid Aguiló-Aguayo; M. Luisa López; Christian Larrigaudière
      Pages: 216 - 225
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Jordi Giné-Bordonaba, Gemma Echeverria, Dolors Ubach, Ingrid Aguiló-Aguayo, M. Luisa López, Christian Larrigaudière
      The aim of this study was to investigate the biochemical and metabolic changes, related to oxidative stress, ethylene and respiration, cell wall modification and primary metabolism, between a high (‘Prime Giant’) and a low (‘Cristalina’) cracking susceptible sweet cherry cultivar during growth and ripening. While cherries are referred as a non-climacteric fruit, our results show that an increase of endogenous ethylene production at earlier fruit developmental stages is parallel to colour development and softening during growth. Higher cracking susceptibility was clearly associated to a higher fruit growth rate and accompanied by an increase net CO2 and ethylene production, on a cherry basis, leading to an enhanced accumulation of oxidative stress markers (i.e. H2O2 and MDA). As observed in other fruit species (i.e. tomatoes) higher cracking susceptibility was also related to enhanced activity of cell wall-modifying enzymes which in turn occurred in parallel to the ethylene rise. Overall, these results suggest that cracking development may be a more complex phenomenon than a mere consequence of altered fruit water absorption or turgor and point out the importance of ethylene on sweet cherry ripening and cracking development.

      PubDate: 2016-12-15T03:38:49Z
      DOI: 10.1016/j.plaphy.2016.12.002
      Issue No: Vol. 111 (2016)
       
  • Role of the C-terminal extension peptide of plastid located glutamine
           synthetase from Medicago truncatula: Crucial for enzyme activity and
           needless for protein import into the plastids
    • Authors: Maria João Ferreira; Diogo Vale; Luis Cunha; Paula Melo
      Pages: 226 - 233
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Maria João Ferreira, Diogo Vale, Luis Cunha, Paula Melo
      Glutamine synthetase (GS), a key enzyme in plant nitrogen metabolism, is encoded by a small family of highly homologous nuclear genes that produce cytosolic (GS1) and plastidic (GS2) isoforms. Compared to GS1, GS2 proteins have two extension peptides, one at the N- and the other at the C-terminus, which show a high degree of conservation among plant species. It has long been known that the N-terminal peptide acts as a transit peptide, targeting the protein to the plastids however, the function of the C-terminal extension is still unknown. To investigate whether the C-terminal extension influences the activity of the enzyme, we produced a C-terminal truncated version of Medicago truncatula GS2a in Escherechia coli and studied its catalytic properties. The activity of the truncated protein was found to be lower than that of MtGS2a and with less affinity for glutamate. The importance of the C-terminal extension for the protein import into the chloroplast was also assessed by transient expression of fluorescently-tagged MtGS2a truncated at the C-terminus, which was correctly detected in the chloroplast. The results obtained in this work demonstrate that the C-terminal extension of M. truncatula GS2a is important for the activity of the enzyme and does not contain crucial information for the import process.

      PubDate: 2016-12-15T03:38:49Z
      DOI: 10.1016/j.plaphy.2016.11.015
      Issue No: Vol. 111 (2016)
       
  • Use of Nicotiana tabacum transplastomic plants engineered to express a
           His-tagged CP47 for the isolation of functional photosystem II core
           complexes
    • Authors: Cristina Pagliano; Luca Bersanini; Rino Cella; Paolo Longoni; Laura Pantaleoni; Abhishek Dass; Sadhu Leelavathi; Vanga Siva Reddy
      Pages: 266 - 273
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Cristina Pagliano, Luca Bersanini, Rino Cella, Paolo Longoni, Laura Pantaleoni, Abhishek Dass, Sadhu Leelavathi, Vanga Siva Reddy
      This work focuses on the development of a molecular tool for purification of Photosystem II (PSII) from Nicotiana tabacum (L.). To this end, the chloroplast psbB gene encoding the CP47 PSII subunit was replaced with an engineered version of the same gene containing a C-terminal His-tag. Molecular analyses assessed the effective integration of the recombinant gene and its expression. Despite not exhibiting any obvious phenotype, the transplastomic plants remained heteroplasmic even after three rounds of regeneration under antibiotic selection. However, the recombinant His-tagged CP47 protein associated in vivo to the other PSII subunits allowing the isolation of a functional PSII core complex, although with low yield of extraction. These results will open up possible perspectives for further spectroscopic and structural studies.

      PubDate: 2016-12-15T03:38:49Z
      DOI: 10.1016/j.plaphy.2016.12.009
      Issue No: Vol. 111 (2016)
       
  • Seed priming improves chilling tolerance in chickpea by modulating
           germination metabolism, trehalose accumulation and carbon assimilation
    • Authors: Muhammad Farooq; Mubshar Hussain; Ahmad Nawaz; Dong-Jin Lee; Salem S. Alghamdi; Kadambot H.M. Siddique
      Pages: 274 - 283
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Muhammad Farooq, Mubshar Hussain, Ahmad Nawaz, Dong-Jin Lee, Salem S. Alghamdi, Kadambot H.M. Siddique
      Chilling stress is one of the major abiotic stresses affecting chickpea productivity worldwide. This study evaluated the potential role of seed priming in improving resistance to chilling stress in chickpea (cv. Punjab, 2008). The priming treatments involved soaking seeds of chickpea cultivar Punjab 2008 in either water for 8 h (on-farm priming), aerated water (hydropriming) for 18 h, or CaCl2 solution (ψs −1.25 MPa; osmopriming) for 18 h. Primed and untreated seeds were grown either at 18/15 °C (control) or 13/10 °C (chilling stress). Chilling stress suppressed the growth of chickpea while seed priming mitigated the adverse effects of chilling stress by improving stand establishment, growth, water relations, photosynthesis, α-amylase activity, sugar metabolism, antioxidant enzyme activity, membrane stability, and leaf accumulation of proline, nitrogen, potassium and soluble phenolics. Seed priming also improved the performance of chickpea under optimal (control) conditions. The overall order of improvement in resistance to chilling by using seed priming was osmopriming > hydropriming > on-farm priming. Osmopriming improved seedling dry weight, specific leaf area, leaf CO2 net assimilation rate, maximal photochemical efficiency of PSII, α-amylase activity, trehalose content and leaf relative water content by 10, 22, 17, 20, 73, 48 and 7%, respectively, relative to the non-primed control under chilling stress. Under optimal temperature conditions, the corresponding values were 30, 32, 16, 10, 83, 75 and 5%, respectively. Sugar metabolism, especially trehalose content, was strongly linked with stand establishment, photosynthesis, antioxidant potential (under chilling stress) and plant biomass. Overall, seed priming improved chickpea performance under both optimal temperature conditions and chilling stress through better germination metabolism and the accumulation of trehalose, which protected from oxidative damage and helped to maintain carbon assimilation and seedling growth.

      PubDate: 2016-12-15T03:38:49Z
      DOI: 10.1016/j.plaphy.2016.12.012
      Issue No: Vol. 111 (2016)
       
  • Euphorbia milii-native bacteria interactions under airborne formaldehyde
           stress: Effect of epiphyte and endophyte inoculation in relation to IAA,
           ethylene and ROS levels
    • Authors: Gholamreza Khaksar; Chairat Treesubsuntorn; Paitip Thiravetyan
      Pages: 284 - 294
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Gholamreza Khaksar, Chairat Treesubsuntorn, Paitip Thiravetyan
      Better understanding of plant-bacteria interactions under stress is of the prime importance for enhancing airborne pollutant phytoremediation. No studies have investigated plant-epiphyte interactions compared to plant-endophyte interactions under airborne formaldehyde stress in terms of plant Indole-3-acetic acid (IAA), ethylene, reactive oxygen species (ROS) levels and pollutant removal efficiency. Euphorbia milii was inoculated with native plant growth-promoting (PGP) endophytic and epiphytic isolates individually to investigate plant-endophyte compared to plant-epiphyte interactions under continuous formaldehyde fumigation. Under airborne formaldehyde stress, endophyte interacts with its host plant closely and provides higher levels of IAA which protected the plant against formaldehyde phytotoxicity by lowering intracellular ROS, ethylene levels and maintaining shoot epiphytic community; hence, higher pollutant removal. However, plant-epiphyte interactions could not provide enough IAA to confer protection against formaldehyde stress; thus, increased ROS and ethylene levels, large decrease in shoot epiphytic population and lower pollutant removal although epiphyte contacts with airborne pollutant directly (has greater access to gaseous formaldehyde). Endophyte-inoculated plant synthesized more tryptophan as a signaling molecule for its associated bacteria to produce IAA compared to the epiphyte-inoculated one. Under stress, PGP endophyte interacts with its host closely; thus, better protection against stress and higher pollutant removal compared to epiphyte which has limited interactions with the host plant; hence, lower pollutant removal.
      Graphical abstract image

      PubDate: 2016-12-15T03:38:49Z
      DOI: 10.1016/j.plaphy.2016.12.011
      Issue No: Vol. 111 (2016)
       
  • Temperature and CO2 dependency of the photosynthetic photon flux density
           responses of leaves of Vitis vinifera cvs. Chardonnay and Merlot grown in
           a hot climate
    • Authors: Dennis H. Greer
      Pages: 295 - 303
      Abstract: Publication date: February 2017
      Source:Plant Physiology and Biochemistry, Volume 111
      Author(s): Dennis H. Greer
      Comparisons of the photosynthetic responses to light and temperature between related cultivars are important to understand how well matched they are to the climate where they are grown. Photosynthetic light responses at a range of leaf temperatures and two CO2 concentrations were measured on leaves of two grapevine cultivars (Vitis vinifera L.) Chardonnay and Merlot vines growing in field conditions. The objective was to assess the interaction between photon flux density (PFD), leaf temperature and CO2 on photosynthesis and to compare the two cultivars. Merlot leaves maintained higher light-saturated rates of photosynthesis at all leaf temperatures compared with the Chardonnay leaves. At low temperatures, a reduced photon yield offset with a high stomatal conductance accounted for the low rates of the Chardonnay leaves. At moderate to high temperatures, photon yields, PFDs at light saturation and stomatal conductances did not account for differences between Merlot and Chardonnay leaves. At elevated CO2 (800 μmol mol−1) concentrations, the differences in photosynthetic performance between the cultivars were enhanced, with 30% higher light saturated rates for Merlot compared with Chardonnay leaves. Merlot berries accumulated more sugar, consistent with published data. These results demonstrate Chardonnay, unlike Merlot, appeared to be poorly matched to the hot climate. However, considering the current market and political trends, low alcoholic wines (and, thus, low sugar grapes) should be preferred. Especially in hot climates, it is always hard to obtain such kind of wines and, thus, the most interesting agronomical challenge, especially for Chardonnay vines could be interpreted in an opposite way.

      PubDate: 2016-12-15T03:38:49Z
      DOI: 10.1016/j.plaphy.2016.12.015
      Issue No: Vol. 111 (2016)
       
  • The long-term resistance mechanisms, critical irrigation threshold and
           relief capacity shown by Eugenia myrtifolia plants in response to saline
           reclaimed water
    • Authors: José Ramón Acosta-Motos; José Antonio Hernández; Sara Álvarez; Gregorio Barba-Espín; María Jesús Sánchez-Blanco
      Abstract: Publication date: Available online 5 December 2016
      Source:Plant Physiology and Biochemistry
      Author(s): José Ramón Acosta-Motos, José Antonio Hernández, Sara Álvarez, Gregorio Barba-Espín, María Jesús Sánchez-Blanco
      Salts present in irrigation water are serious problems for commercial horticulture, particularly in semi-arid regions. Reclaimed water (RW) typically contains, among others elements, high levels of salts, boron and heavy metal. Phytotoxic ion accumulation in the substrate has been linked to different electric conductivities of the treatments. Based on these premises, we studied the long-term effect of three reclaimed water treatments with different saline concentrations on Eugenia myrtifolia plants. We also looked at the ability of these plants to recover when no drainage was applied. The RW with the highest electric conductivity (RW3, EC = 6.96 dS m−1) provoked a number of responses to salinity in these plants, including: 1) accumulation and extrusion of phytotoxic ions in roots; 2) a decrease in the shoot/root ratio, leaf area, number of leaves; 3) a decrease in root hydraulic conductivity, leaf water potential, the relative water content of leaves, leaf stomatal conductance, the leaf photosynthetic rate, water-use efficiency and accumulated evapotranspiration in order to limit water loss; and 4) changes in the antioxidant defence mechanisms. These different responses induced oxidative stress, which can explain the damage caused in the membranes, leading to the death of RW3 plants during the relief period. The behaviour observed in RW2 plants was slightly better compared with RW3 plants, although at the end of the experiment about 55% of the RW2 plants also died, however RW containing low salinity level (RW1, EC = 2.97 dS m−1) can be effective for plant irrigation.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.12.003
       
  • Expression profiles and hormonal regulation of tobacco NtEXGT gene and its
           involvement in abiotic stress response
    • Authors: Bulat Kuluev; Elena Mikhaylova Zoya Berezhneva Yuri Nikonorov Bogdan Postrigan
      Abstract: Publication date: Available online 5 December 2016
      Source:Plant Physiology and Biochemistry
      Author(s): Bulat Kuluev, Elena Mikhaylova, Zoya Berezhneva, Yuri Nikonorov, Bogdan Postrigan, Guzel Kudoyarova, Aleksey Chemeris
      Despite the intensive study of xyloglucan endotransglucosylases/hydrolases, their multifaceted role in plant growth regulation in changing environmental conditions is not yet clarified. The functional role of the large number of genes encoding this group of enzymes is also still unclear. NtEXGT gene encodes one of xyloglucan endotransglucosylases/hydrolases (XTHs) of Nicotiana tabacum L. The highest level of NtEXGT gene expression was detected in young flowers and leaves near the shoot apex. Expression of the NtEXGT gene in leaves was induced by cytokinins, auxins, brassinosteroids and gibberellins. NtEXGT gene was also up-regulated by salinity, drought, cold, cadmium and 10 μM abscisic acid treatments and down-regulated in response to 0 °C and 100 μM abscisic acid. Pretreatment of leaves with fluridone contributed to smaller increase in the level of NtEXGT transcripts in response to drought stress. These data suggest that NtEXGT gene is ABA-regulated and probably implicated in ABA-dependent signaling in response to stress factors. 35S::NtEXGT plants of tobacco showed higher rate of root growth under salt-stress conditions, greater frost and heat tolerance as compared with the wild type tobacco plants.

      PubDate: 2016-12-08T03:16:39Z
       
  • Proteomic analysis of the compatible interaction of wheat and powdery
           mildew (Blumeria graminis f. sp. tritici)
    • Authors: Jie Li; Xiwen Yang; Xinhao Liu; Haibo Yu; Congyang Du; Mengda Li; Dexian He
      Abstract: Publication date: Available online 5 December 2016
      Source:Plant Physiology and Biochemistry
      Author(s): Jie Li, Xiwen Yang, Xinhao Liu, Haibo Yu, Congyang Du, Mengda Li, Dexian He
      Proteome characteristics of wheat leaves with the powdery mildew pathogen Blumeria graminis f. sp. tritici (Bgt) infection were investigated by two-dimensional electrophoresis and tandem MALDI-TOF/TOF-MS. We identified 46 unique proteins which were differentially expressed at 24, 48, and 72 h post-inoculation. The functional classification of these proteins showed that most of them were involved in photosynthesis, carbohydrate and nitrogen metabolism, defense responses, and signal transduction. Upregulated proteins included primary metabolism pathways and defense responses, while proteins related to photosynthesis and signal transduction were mostly downregulated. As expected, more antioxidative proteins were activated at the later infection stage than the earlier stage, suggesting that the antioxidative system of host plays a role in maintaining the compatible interaction between wheat and powdery mildew. A high accumulation of 6-phosphogluconate dehydrogenase and isocitrate dehydrogenase in infected leaves indicated the regulation of the TCA cycle and pentose phosphate pathway in parallel to the activation of host defenses. The downregulation of MAPK5 could be facilitated for the compatible interaction of wheat plants and Bgt. qRT-PCR analysis supported the data of protein expression profiles. Our results reveal the relevance of primary plant metabolism and defense responses during compatible interaction, and provide new insights into the biology of susceptible wheat in response to Bgt infection.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.12.006
       
  • Ionomic and physiological responses to low nitrogen stress in Tibetan wild
           and cultivated barley
    • Authors: Xiaoyan Quan; Jianbin Zeng; Zhigang Han; Guoping Zhang
      Abstract: Publication date: Available online 6 December 2016
      Source:Plant Physiology and Biochemistry
      Author(s): Xiaoyan Quan, Jianbin Zeng, Zhigang Han, Guoping Zhang
      In a previous study, we identified the low-nitrogen (LN) tolerant accessions from the Tibetan wild barley (Hordeum vulgare subsp. spontaneum). In this study, two wild barley genotypes (XZ149, LN-tolerant and XZ56, LN-sensitive) and a barley cultivar ZD9 (H. vulgare) were used to determine the LN tolerant mechanism underlying the wild barley in the ionomic and physiological aspects. XZ149 exhibited higher LN tolerance with highest relative dry weight and N accumulation among three barley genotypes under LN stress. When exposed to LN stress, XZ149 had more N transportation from roots to leaves, and remained relatively higher activities of nitrate reductase (NR, EC.1.7.1.1) and glutamine synthetase (GS, EC.6.3.1.2) in leaves than other two genotypes, ensuring its higher capacity of N assimilation and utilization. The ionome analysis showed that LN stress had a significant effect on tissue ionome and the effect was genotypic and tissue-specific difference. On the whole, XZ149 maintained more stable Mn and Cu contents, and less reduction of root P, K and Ca contents than XZ56 and ZD9 when exposed to LN stress. It may be assumed that more N movement into shoots, greater N assimilating capacity and specific rearrangement of nutrient element levels less change in tissues under LN stress are attributed to LN tolerance in XZ149.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.12.008
       
  • Effects of Fe-deficient conditions on Fe uptake and utilization in
           P-efficient soybean
    • Authors: Wei Qiu; Jing Dai; Nanqi Wang; Xiaotong Guo; Xiaoli Zhang; Yuanmei Zuo
      Abstract: Publication date: Available online 7 December 2016
      Source:Plant Physiology and Biochemistry
      Author(s): Wei Qiu, Jing Dai, Nanqi Wang, Xiaotong Guo, Xiaoli Zhang, Yuanmei Zuo
      Phosphorus (P)-efficient soybean (Glycine max) plants absorb and utilize P with high efficiency. To investigate the effects of iron (Fe)-deficient conditions on the absorption and utilization of Fe in P-efficient soybean plants, two soybean cultivars with different P efficiency, the 03-3 (P-efficient variety) and Bd-2 (P-inefficient variety), were used in this study. The two soybean cultivars were grown in nutrient solution containing Fe concentrations of 0 (Fe0), 20 (Fe20), 40 (Fe40), or 80 (Fe80) μM for 7 days. The Fe reductase activity of roots was higher in 03-3 plants grown under the Fe0, Fe20, and Fe40 treatments than in Bd-2 plants and the total Fe uptake was greater in 03-3 plants under the Fe40 treatment. GmFRD3a was much more highly expressed in the stem of 03-3 than in that of Bd-2, and significantly more iron was transported to 03-3 plant shoots during Fe0 treatment. Chlorosis in young leaves caused by Fe deficiency under the Fe0 and Fe20 treatments was alleviated by increased Fe concentration in shoots. Increased levels of active Fe in young 03-3 leaves under Fe-deprivation conditions (Fe0) and maintenance of stable Fe concentrations in 03-3 shoots subjected to Fe20, Fe40, and Fe80 treatments suggested that the P-efficient 03-3 cultivar is also Fe-efficient. It is suggested that 03-3 soybean cultivar should be a good resource for application to farm field.

      PubDate: 2016-12-08T03:16:39Z
      DOI: 10.1016/j.plaphy.2016.12.010
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
Home (Search)
Subjects A-Z
Publishers A-Z
Customise
APIs
Your IP address: 54.161.249.135
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-2016