Articles

5(5) September 2012 issue
 
September 2012 issue
Southern Cross Publishing Group©2012
Australia




Research Note

Polymorphism analysis of cryopreserved Dendrobium Bobby Messina protocorm-like bodies (PLBs) using RAPD markers

Jessica Jeyanthi James Antony, Ranjetta Poobathy, Monica Danial, Uma Rani Sinniah, Sreeramanan Subramaniam

School of Biological Sciences, Universiti Sains Malaysia (USM), Minden Heights, 11800, Penang, Malaysia

Abstract 
Dendrobium Bobby Messina, a sympodial orchid, is a new Dendrobium orchid hybrid from Indonesia with the parentage of (Imelda Romualdez × Jaquelyn Thomas). This orchid is cultivated for its cut flowers and potted plants, and is valued for its attractive flowers. Cryopreservation is a feasible long term storage method, whereby plants are stored at ultra low temperature using liquid nitrogen (-196
°C). Protocorm-like bodies (PLBs) are an attractive target explant for orchid cryopreservation. In this study, cryopreservation using plant vitrification solution 2 (PVS2) was carried out on PLBs of Dendrobium Bobby Messina using optimum conditions, and growth recovery was obtained at 40%. In the screening of suitable primers to detect polymorphism in both cryopreserved and non-cryopreserved PLBs in comparison with the stock culture, 20 primers were used but only 10 primers were able to generate bands. However, the number of bands produced in cryopreserved and non-cryopreserved PLBs from 3 primers and 1 primer indicated polymorphism and partial polymorphism respectively. The RAPD results from 6 selected primers indicated that the genetic stability of PLBs following cryopreservation was maintained. Hence, this method can be utilised as a potential cryopreservation approach for the germplasm conservation of Dendrobium Bobby Messina orchid.

Pages 427-431 | Full Text PDF
Photosynthetic and chlorophyll fluorescence regulation of upland cotton (Gossiypium hirsutum L.) under drought conditions

Dongxiao Li, Cundong Li, Hongchun Sun, Liantao Liu, Yongjiang Zhang

Key Laboratory of Crop Growth Regulation of Hebei Provinced, Agricultural University of Hebei province, Baoding 071001, China
Key Laboratory of Agricultural Water Resources & Hebei Key Laboratory of Agricultural Water-Saving, Centre for Agricultural Resources Research, Institute of Genetic and Developmental Biology, CAS, Shijiazhuang, P.R. China

Abstract
To investigate physiological characteristics of photosynthesis at different stages of growth, the transgenic cultivar Lumianyan28 was treated under two conditions with relative water content of < 60% (drought treatment) and 70-80% (well watered control), respectively. Results obtained from leaves of main stem showed that drought decreased the transpiration efficiency and inner transpiration efficiency of functional leaves which refers to the forth main stem leave from top before tip pruning, and thereafter, refers to the third one or the second one in the later period. It can be inferred that plants were most sensitive to soil drought at the initial bloom stage. Due possibly to the reduction of thylakoid stacking, the content of chlorophyll a/b and net photosynthetic rate of the water-stressed plants were significantly lower than those of the well-watered control plants at the initial bloom stage. The transpiration rate of the functional leaves under drought treatment was remarkably higher than those of control plants at the bud stage, showing the relative significance of transpiration. The photosynthetic electron transport rate (ETR) of the main stem leaves correlated with the net photosynthetic rate under drought treatment (correlation coefficient=0.907*). However, such a correlation was not detected in the well-watered leaves. These results suggested that regulating photosynthetic system at crucial stages was the defense response of cotton plant to drought. However, this ability was very limited and progressively reduced along with prolonged drought.

Pages 432-437 | Full Text PDF
A WRKY transcription factor gene isolated from Poncirus trifoliata shows differential responses to cold and drought stresses

Mehtap Sahin-Çevik

Department of Agricultural Biotechnology, Faculty of Agriculture, Süleyman Demirel University, Isparta, 32260, TURKEY

Abstract
Partial sequences of a number of cDNAs showing homology with WRKY genes were amplified from two-day cold-acclimated Poncirus trifoliata by reverse transcription-polymerase chain reaction (RT-PCR) using degenerate primers designed based on conserved signature sequences of the WRKY domain. The full-length sequence of one of these cDNAs designated as PtrWRKY2 was obtained using rapid amplification of cDNA ends (RACE) method. PtrWRKY2 cDNA was 2,070 bp in length containing an open reading frame (ORF) encoding a polypeptide of 540 amino acids. The polypeptide was homologous to WRKY transcription factors (TFs) having double WRKY domains with Cys2His2 signature motif. The PtrWRKY2 gene was clustered with putative WRKY TFs having double WRKY domains and showed close phylogenetic relation with putative WRKY TFs mostly from woody perennial plants. The expression of the PtrWRKY2 gene was analyzed by Northern blot in cold-hardy Poncirus and cold-sensitive Citrus species, Citrus grandis (pummelo) having the same gene with more than 95% nucleotide sequence homology. The results revealed that the expression of the PtrWRKY2 gene was initially induced in response to cold in both cold-hardy Poncirus and cold-sensitive pummelo; however, the expression was decreased at 1 h of cold acclimation and then, clearly repressed in Poncirus and pummelo. On the other hand, drought stress had no effect on the expression of the PtrWRKY2 gene in pummelo, but its expression was repressed by drought stress in Poncirus indicating a negative regulation. The results showed that PtrWRKY2 encodes a WRKY TF and its expression showed differential responses to cold acclimation and dehydration stress in Poncirus and Citrus

Pages 438-445 | Full Text PDF
Exogenous ABA and polyamines enhanced salvianolic acids contents in hairy root cultures of Salvia miltiorrhiza Bge. f.alba

Gangping Hao, Haiwei Ji, Yanlin Li, Renjiu Shi, Jianmei Wang, Lei Feng, Luqi Huang

Department of Biochemistry, Taishan Medical University, Tai’an 271000, People’s Republic of China
Institute of Chinese Materia Medica, Chinese Academy of Chinese Medical Science, Beijing 100700, China


Abstract
Salvia miltiorrhiza Bge. f.alba is a variety of S. miltiorrhiza Bunge which is a well-known and very important traditional chinese medicinal herb. In this study, we successfully induced hairy roots from leaves of S. miltiorrhiza Bge.f.alba by Agrobacterium rhizogenes ACCC10060. As determined by high performance liquid chromatography (HPLC), these hairy root cultures had the ability to produce salvianolic acid B and salvianic acid A, two main salvianolic acids in S. miltiorrhiza Bge.f.alba. The effects of ABA and polyamines (PAs, including putrescine (Put), spermidine (Spd) and spermine (Spe) on salvianolic acids production were studied. The results showed that phenylalanine ammonia-lyase (PAL) activity, salvianolic acid B and salvianic acid A contents increased 1.8, 2.0 and 3.3 times after 80
µmol L-1 ABA treatment for 10 d, 12 d and 10 d, respectively. Similarly, Put was the most effective polyamine among the three PAs, and the effects of Put and Spd for salvianolic acids production were better than that of Spe. Moreover, hairy root cultures treated with 50 mg L-1 Put produced the highest levels of hairy root growth (13.23 g L-1 culture), salvianolic acid B (12.13 mg g-1 DW) and salvianic acid A (3.95 mg g-1 DW) among the three PAs. After treated with the mixture of Put and Spd (50 mg L-1each) for 10 d, 12 d and 10 d respectively, PAL activity, salvianolic acid B and salvianic acid A production were about 1.82, 2.05 and 3.45 times as those in the control, respectively. These findings indicate that exogenous ABA and PAs can enhance two salvianolic acids production in hairy root cultures of S. miltiorrhiza Bge.f.alba.

Pages 446-452 | Full Text PDF
Primers to amplify flowering locus T (FT) transcript in mango (Mangifera indica) and their potential use in other angiosperms

Sergio de los Santos-Villalobos, Fannie Isela Parra-Cota, Stefan de-Folter, Juan José Peña-Cabriales

Centro de Investigación y de Estudios Avanzados-IPN (CINVESTAV), Unidad Irapuato. Km. 9.6 Libramiento Norte, Carretera Irapuato-León, CP 36500, Irapuato, Guanajuato, México
Laboratorio Nacional de Genómica para la Biodiversidad (LANGEBIO), CINVESTAV-IPN, Km. 9.6 Libramiento Norte, Carretera Irapuato-León, CP 36821, Irapuato, Guanajuato, México

Abstract
Mango (Mangifera indica) is a commercially important fruit crop around the world. So far, Flowering Locus T (FT), a floral integrator gene, has not been identified in this plant as well as in other economically important angiosperms. Two pairs of primers to amplify fragments of FT transcripts from M. indica were designed using an alignment of forty-one amino acid sequences of this transcript belonging to fifteen angiosperm species. Designed primers, FTf1/FTr2 and FTf2/FTr2, amplified fragments of approximately 210 and 150 bp, respectively, which were sequenced by Sanger platform. Sequences obtained were analyzed and compared, using BLAST, with those of FT deposited in the NCBI GenBank database, FT transcripts of 207 bp (Accession No. JX316911) and 147 bp (Accession No. JX316912) from M. indica showed high identity with FT of Populus nigra (86% and 84%, respectively). In addition, FTf2/FTr2 was able to amplify 150 bp fragments from Duranta dombeyana (Accession No. JX316913), Gazania linearis (Accession No. JX316915), and Lantana camara (Accession No. JX316914), with significant identity to FT of Xanthium strumarium (82%), Helianthus annuus (91%), and Ficus carica (79%), respectively. Furthermore, phylogenetic relationship analysis showed that the fragment of 147 bp from M. indica FT transcript has more similarity to those belonging to the subclass Rosidae, while FT from D. dombeyana, G. linearis and L. camara are more related to the subclass Asteridae. Overall, these primers may be useful to amplify fragments of FT transcript from other angiosperm species for a variety of downstream applications, such as monitoring their expression profiles under certain conditions, isolation of FT full-length transcripts, etc. This will lead to propose more precise models and alternatives to control the flowering in plants of interest.

Pages 453-457 | Full Text PDF
Review article

A decade of plant proteomics in South Korea: the international plant proteomics organization (inppo) perspective and involvement


Su-ji Lee, Kyu Young Kang, Nam-Soo Jwa, Dea-Wook Kim, Ganesh Kumar Agrawal, Abhijit Sarkar, Renu Deswal, Jenny Renaut , Dominique Job, Randeep Rakwal, and Sun Tae Kim

Department of Plant Bioscience, Pusan National University, Miryang, 627-706, South Korea
Division of Applied Life Science (BK21 program), Gyeongsang National University, Jinju 660-701, South Korea
Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701, South Korea
Department of Molecular Biology, Sejong University, Gunja-dong, Seoul 143-747, South Korea
National Institute of Crop Science, Rural Developmental Administration, Suwon 441-857, South Korea
Research Laboratory for Biotechnology and Biochemistry (RLABB), GPO Box 13265, Kathmandu, Nepal
CSIR-Senior Research Fellow, Department of Botany, Banaras Hindu University, Varanasi 221005, India
Department of Botany, University of Delhi, Delhi-7, India
Centre de Recherche Public-Gabriel Lippmann, Department of Environment and Agrobiotechnologies, Belvaux, GD, Luxembourg
CNRS/UCBL/INSA/Bayer CropScience Joint Laboratory, UMR 5240, Bayer CropScience, 14-20 rue Pierre BAIZET, F-69263, Lyon cedex, France

Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba Ibaraki 305-8572, Japan
Department of Anatomy I, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555, Japan

Abstract
In this review, we discuss the contribution of proteomics focusing on plant responses to various environmental stimuli in South Korea. Due to improvements in proteomics methods and applications in various research fields in South Korea, plant proteomics have and will continue to provide systematic approaches to address biological questions and understanding of the network between plants and environmental stimuli. We also introduce the International Plant Proteomics Organization (INPPO; www.inppo.com <http://www.inppo.com>), a global initiative to advance plant proteomics research worldwide that is also designed to highlight national plant proteomics topics via a common global platform. Thus, we expect INPPO to generate further interest and activity among South Korean plant proteomics researchers and within the plant biology scientific community. Finally, to help network the plant proteomics community in South Korea, the creation of an INPPO-South Korea chapter is proposed.


Pages 458-465 | Full Text PDF
Research Note

Production of astragaloside and flavones from adventitious root cultures of Astragalus membranaceus var. mongholicus

Aye Aye Thwe, Nguyen Thi Thanh Mai, Xiaohua Li, Yeji Kim, Yeon Bok Kim, Md. Romij Uddin, Young Seon Kim, Hanhong Bae, Haeng Hoon Kim, Mi Young Lee and
Sang Un Park

Department of Crop Science, College of Agriculture & Life Sciences, Chungnam National University, 79 Daehangno, Yuseong-gu, Daejeon, 305-764, Korea
TKM-Based Herbal Drug Research Group Researcher, Korea Institute of Oriental Medicine, 1672 Yuseongdae-ro, Yuseong-gu, Daejeon, 305-811, Korea
School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Korea
Department of Well-being Resources, Sunchon National University, 413 Jungangno, Suncheon, Jeollanam-do, 40-742, Korea

Abstract
Many plants contain various secondary metabolites that have medicinal value. Their content varies across plant parts. We carried out in vitro adventitious root induction from leaf explants of Huang-qi (Astragalus membranaceus) using different nutrient media supplemented with various plant hormones. The level of astragaloside and flavones were analyzed from the adventitious roots of A. membranaceus grown under these different media conditions. Among the different media and plant hormones, Murashige and Skoog medium supplemented with 1.0 mg/L 1-naphthaleneacetic acid resulted in the greatest degree of adventitious root induction. The highest concentration of calycosin (11.7 µg/g dry weight), calycosin-7-glu (13.3 µg/g dry weight), and glucoraphanin (241.9 µg/g dry weight) were observed in roots grown in half-strength Schenk & Hildebrandt mineral solution, half-strength Gamborg’s B5 medium, and full-strength Gamborg’s B5 media, respectively.

Pages 466-470 | Full Text PDF
| Supplementary data
Large-scale identification of differentially expressed genes in maize inbreds susceptible and resistant to Fusarium ear rot

Yuan Guangsheng, Zhang Zhiming, Xiang Kui, Zhao Maojun, Shen Yaou, Pan Guangtang

Key Laboratory of Crop Genetic Resources and Improvement, Ministry of Education, Maize Research Institute, Sichuan Agricultural University, Ya’an 625014, Sichuan Province, China

Abstract
Fusarium ear rot is a destructive disease in maize mostly caused by the fungus Fusarium verticillioides (FV), which results in reduction of grain yield. To understand the host response to FV infection in maize, we examined gene expression changes in bract tissue of resistant inbred line Bt-1, as well as susceptible inbred line Ye478, at the fourth day after inoculation with FV, based on the genechip experiment. Results showed that seven expressed genes were specifically up-regulated (>1.5-fold) in response to FV in Ye478, while 482 genes were significantly up-regulated in Bt-1, compared to their controls. Overall, the identity of the up-regulated genes indicates that the response of maize bract tissue to FV infection involves a complicated host-pathogen interaction. To the best of our knowledge, this study represents the first large-scale identification of genes differentially expressed in maize ear rot after FV infection, providing new insight into the host processes potentially involved in maize defense against this pathogen.

Pages 471-475 | Full Text PDF | Supplementary data
Stigmasterol treatment increases salt stress tolerance of faba bean plants by enhancing antioxidant systems

R. A. Hassanein, H. A. Hashem, and R. R. Khalil

Department of Botany, Faculty of Science, Ain Shams University, Cairo, Egypt
Department of Botany, Faculty of Science, Benha University, Benha, Egypt

Abstract 
The effect of different concentrations of NaCl (100, 150, and 200 mM) on cell membrane stability, photosynthetic pigment and carbohydrate contents, antioxidant enzymes activities, glutathione contents, and lipid peroxidation (malondialdehyde content) in faba bean (Vicia faba) leaves were investigated. In addition, the role of stigmasterol, a promising plant development regulatory substance in increasing tolerance to salt stress was evaluated. The results revealed that salt-stressed bean plants treated with stigmasterol had an increased membrane stability index, and photosynthetic pigment and carbohydrate contents compared with salt-stressed plants untreated with stigmasterol. The level of antioxidant system components (catalase, ascorbic acid peroxidase, and reduced glutathione) increased in response to stigmasterol treatment. Enhanced antioxidant activities helped to decrease oxidative damage from salt and develop tolerance against salt stress in stigmasterol-treated faba bean plants. An increase in the degree of salt tolerance induced by stigmasterol was indicated by the improvement of the membrane stability index, photosynthetic activity and consequently the carbohydrate pool. The data provided evidence that stigmasterol treatment reduced the adverse effects of salt stress on faba bean plants, and might play a key role in providing stress tolerance by stimulation of the antioxidant system as a stress protection mechanism.

Pages 476-485 | Full Text PDF
The alleviative effect of salicylic acid on the physiological indices of the seedling leaves in six different wheat genotypes under lead stress

Weiyi Song, Aizhen Zheng, Hongbo Shao, Liye Chu, Marian Brestic and Zhengbin Zhang  

Department of Life Science, Shangqiu Normal University, 476000, Shangqiu, China
The CAS /Shandong Provincial Key Laboratory of Coastal Environmental Processes, Yantai Institute of Costal Zone Research, Chinese Academy of Sciences (CAS), 266003, Yantai, China
Institute of Life Sciences, Qingdao University of Science and Technology (QUST), 266042, Qingdao, China
Center for Agricultural Resources Research, Institute of Genetic and Developmental Biology, Zone Research, Chinese Academy of Sciences (CAS), 050021, Shijiazhuang, China  
Department of Plant Physiology, Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia

Abstract
In this research, relevant physiological indices were measured in seedling leaves of six different wheat genotypes growing at three-leaves stage. The seedlings were cultured under hydroponic cultivation and treated by different lead ion (Pb2+) treatments (namely 10, 50, 100, 200 mg L-1 Pb2+ stresses, respectively) and Pb2+-SA (salicylic acid) jointed-treatments (namely 200 mg L-1 SA-alleviated 10, 50, 100, 200 mg L-1 Pb2+ stresses, respectively). The results showed that stress induced by the application of Pb2+ triggered significant inhibitory effects on indices such as chlorophyll content, ascorbate peroxidase (APX) activity, catalase (CAT) activity, malonic dialdehyde (MDA) content and proline content. Moreover, application of SA exerted certain alleviative effects on these indices in seedling leaves of all genotypes. Peroxidase (POD) activity, superoxide dismutase (SOD) activity and soluble sugar content were significantly affected by inhibitory effects of Pb2+ stress, while SA exerted limited alleviative effects on these parameters. For all physiological indices, SA had the most apparent alleviative effects on seedling leaves of all genotypes treated by the maximum Pb2+ concentration, namely, 200 mg L-1 Pb2+ stress. No significant differences were observed in response of all genotypes to stress, in terms of the change in physiological indices values, indicating that hydroponic cultivation at same nutrition conditions minimized the differences in stress tolerance or resistance of all genotypes. These data provide a basic study on physiological mechanism of wheat resistance (tolerance) to heavy metal stress.

Pages 486-493 | Full Text PDF
In silico characterization and molecular modeling of GntR family regulators in Xanthomonas axonopodis pv. citri: Implications for primary metabolism or virulence

Liping Liu, Jinwang Qu, Na Li, Dazhi Li, Guiyou Long and Ziniu Deng

Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Hunan Agricultural University, Changsha 410128, China
National Center for Citrus Improvement, Hunan Agricultural University, Changsha 410128, China

Abstract
Xanthomonas axonopodis pv. citri (Xac) causes citrus canker, a serious threat to the citrus industry worldwide. The GntR family is a group of helix-turn-helix bacterial transcriptional regulators, and may be involved in bacterial virulence or primary metabolism. In this study, genome-wide sequence analysis of Xac strain 306 revealed that two genes encode the FadR-like regulators. Moreover, one gene encodes the YtrA-like regulator, one gene MocR-like regulator, and three the HutC-like regulators. Furthermore, an attempt was done to predict the 3D models of these regulators using I-TASSER server. Backbone conformation of the modeled structure by PROCHECK revealed that more than 95% of the residues fall in the allowed regions. ProQ results confirmed the high quality of modeled structure and verified the 3D profiles at satisfying level. Considering the auto-regulatory characteristic of GntR-like genes, the potential binding sites were identified by analyzing the primary amino acid sequences. On the basis of reciprocal BLAST search, GntR orthologs in other members of the genus Xanthomonas were also identified. Our analysis provides valuable clues for initiation of experimental characterization of these regulators and enhances our understanding about their roles in citrus-Xac interactions.

Pages 494-502 | Full Text PDF | Supplementary data
Plant Omics Journal | September 2012 issue