Showing papers in "Journal of Plant Biochemistry & Physiology in 2014"

Salinity Tolerance in Plants: Revisiting the Role of Sulfur Metabolites

Abstract: Salinity is becoming a major threat to plant productivity loss in agricultural system. Plants respond to saline environment by modulating the inherent mechanisms to adjust to the changing environment. The understanding of the mechanisms that plants operate under saline environment is essential beginning in efforts to reduce the adverse effects of salinity stress. The agricultural system is tightly linked with the fertilizer input and thus the judicious application of fertilizers is expected to lead positive effects in reversing the salinity effects. Sulfur is a macronutrient with essential roles in plant development under optimal and stressful environment. Several compounds are synthesized from sulfur metabolism useful in reversing the adverse effects of abiotic stress because of their free radicals scavenging property. Sulfur-containing metabolites, amino acids (cysteine and methionine), vitamins (biotin and thiamine), thioredoxin system, glutathione lipoic acid and glucosinolats have potential to promote or modify physiological and molecular processes under salinity stress in plants. Thus, modulation of sulfur metabolites production could alter physiological and molecular mechanisms to provide tolerance against salinity. The present review discusses the role of sulfur-containing compounds in modifying various physiological and molecular processes in plants to confer salinity tolerance in plants.

Impact of Gold Nanoparticles on Physiological and Biochemical Characteristics of Brassica juncea

Abstract: Agricultural crops are an essential base component of all ecosystems and it is important to assess the impact of nanoparticles on them and the risks involved. In this study we have investigated the impact of the different concentrations (ppm) of citrate stabilized gold nanoparticles (GNPs) ranging from 100 to 400 on physiological and biochemical parameters of the seedlings of Brassica juncea as a model oil crop system. GNPs were synthesized and characterized through Uv-visible spectra and transmission electron microscopy. The qualitative accumulation of GNPs into seedlings of Brassica juncea was ascertained through cyclic voltammetry and Laser Induced Breakdown Spectra (LIBS). Exposure of GNPs caused a decrease in overall growth of Brassica juncea was attributed to increase in free radical stress, supported by a general increase in biomarkers such as antioxidative enzymes, proline and hydrogen peroxide due to the formation of reactive oxygen species.

The Ethylene: From Senescence Hormone to Key Player in PlantMetabolism

Abstract: Senescence is a natural process that denotes completion of life cycle after the release of hormones responsible for the process. From evolutionary point of view, senescence was a phenomenon in the populations with the context of natural selection and persistence of plants. The available information from the plant demography and plant biology suggested that plants offer unique comparative studies on senescence. In the mid-1870, it was observed by Girardin [1] that certain trees and varieties of plants were defoliated when exposed to an illuminating gas [2]. Further, Neljubonv [3] suggested that the illuminating gas was ethylene responsible for fall of leaves, and that the olefin was identified as the biologically active component of the illuminating gas. It has been established that high ethylene concentration in plants causes senescence and loss of other plant’s functions, such as chlorophyll degradation, decline in photosynthetic enzyme activity and leaf abscission [4-7]. The ability of ethylene to induce senescence and abscission was also considered merely as an interesting and remarkable curiosity. Ethylene-induced senescence was found to be age-related phenomenon that was induced only after the leaves reached at specific developmental stage [8,9]. At the first developmental leaf stage, ethylene production is high and subsequently declines when leaves reach the fully expanded stage, and finally increases again during senescence. It has been found that ethylene precursor; 1-aminocyclopropane-1carboxylic acid (ACC) content and ethylene production increases in senescing leaves [10]. Later researches on ethylene suggested its contradictory reports on plant functions. The ethylene response is found variable and depends on the plant species because every plant or its part has different sensitivity to ethylene. Moreover, it has been now established that ethylene is an endogenous regulator not only for senescence but also of plant development under optimal and stressful environments. Therefore, it is appropriate to look into whether ethylene controls or influences plants developmental processes. Recent developments in ethylene biology indicated that ethylene plays important role in the regulation of plant metabolism under both optimal and different stressful environments [11-16] (Table 1).

Expansins: Cell Wall Remodeling Proteins with a Potential Function inPlant Defense

Abstract: Cell wall (CW) performs a number of important functions. This distinctive feature of plants determines cell structure, and plays major roles in intercellular communication and plant-microbe interactions, including defense responses against potential pathogens. Expansins are novel plant CW loosening proteins, are mainly involved in the pH-dependent extension of plant CWs that is called acid growth [1,2]. These plant CW remodeling proteins have important roles in plant cell growth, fruit softening, abscission, and emergence of root hairs, pollen tube invasion of the stigma and style, meristem function, pathogenicity and developmental processes. Expansins are linked with cell growth and CW changes that are induced by a number of plant hormones. In plants, two main families of expansin genes have been discovered: -expanins (

SNP as an Effective Donor of Nitric Oxide for in vitro Plant Cell and Tissue Culture

Abstract: Nitric oxide (NO) is a bioactive inorganic gas, free radical and highly labile of a low molecular weight and a half life of less than six seconds. It contains an unpaired electron in its outer orbital and because this fact, it bears the characteristics of a radical that can win or lose an electron and be converted to one of three different species: the radical (NO∙), the nitrosonium cation (NO+) or nitroxyl anion (NO-), which explains its high reactivity and its tendency to bind with reduced heme proteins [1]. These three forms of NO are swappable within the cell and are strongly dependent on the redox state thereof. The radical NO diffuses freely in aqueous solutions and is able to cross lipid membranes, move within cell compartments and from cell to cell [2].

The Effect of Palm Kernel Oil (PKO) Biodiesel-Contaminated Soil onMorphological and Biochemical Properties of Zea mays

Abstract: The effect of palm kernel oil (PKO) biodiesel-contaminated soil on morphological and biochemical properties of Zea mays (corn) was investigated Thirty polythene pots with drainage holes at the bottom, each containing 10 kg of surface soil, were randomly placed on a table in the screenhouse in a factorial combination of five treatment levels (4%, 30%, 20%, 10% and 0% w/w) of PKO biodiesel and were designated S4, S3, S2, S1 and S0 respectively Three seeds of maize per pot were planted Growth parameters (plant height, stem girth, relative water content (RWC), selected leaf properties (chlorophyll content (SPAD value) and soluble protein content (SPC)) and antioxidant indices were determined in the corn over a period of eight weeks after planting (WAP) Results showed that growth of corn planted in contaminated soil was significantly lower (p<005) than that of control Corn planted in the contaminated soil also showed a significant increase (p<005) in superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX) and glutathione reductase (GR) activities in leaves when compared with control plants The results suggest that PKO biodiesel-contaminated soil hindered availability of water, air and nutrients to corn roots, creating a drought condition which could induce oxidative stress in the plant and consequently retarding growth and yield of corn plant

Increasing Circulating Testosterone: Impact of Herbal Dietary Supplements

Abstract: Low circulating testosterone levels can present numerous problems related to the overall health and well-being of individuals, men in particular. This finding is well-documented in the literature and low testosterone appears more prevalent in older men, in particular those who are physically inactive and who present with elevated levels of body fat. Multiple botanical (herbal) products have been claimed to elevate circulating testosterone in men; however, data pertaining to the use of such herbal preparations obtained from human clinical trials are limited. This review examines the research to date pertaining to the use of herbal ingredients with regards to their ability to elevate blood testosterone levels. A collective summary of the findings indicate that certain herbal supplements may actually yield an increase in testosterone (e.g., Longjack root), while most others have little to no evidence in support of their use in human subjects. Additional, well-controlled clinical trials are needed to generate data relative to the use of herbal dietary supplements to increase circulating testosterone.

Plant Age Affects Wound-Induced Senescence in Lactuca Sativa L

Abstract: In the present study we investigated the performance of dark-stored wounded leaf discs and pieces (to some extent mimicking fresh-cut product) of Lactuca sativa L. in relation to the physiological maturity at harvest. We used two related genotypes, i.e. a green (cv. Troubadour) and a red butterhead (cv. Teodore) differing in their pigment levels. For both genotypes, senescence of the wounded (fresh-cut) tissue prepared from leaves of younger plants was significantly delayed compared to wounded tissue prepared from the more mature plants. Shelf-life (time to unacceptable quality) of fresh-cut was doubled when plants were harvested one week before the commercial harvesting date. To explain differences in shelf-life between fresh-cut products prepared from plants harvested at different age, a number of physiological and nutritional parameters were determined at harvest. The red lettuce contained about two times more chlorophyll, carotenoids, and polyphenolic antioxidants than the green lettuce, but the shelf-life of both genotypes was about similar. Increasing the amount of pigments and polyphenols through application of LED light (with high percentage blue) during cultivation did not affect the shelf life of the wounded leaf tissue. The content of chlorophyll, carotenoids, phenolic compounds, as well as total antioxidant capacity was not affected by age of the plants for either genotype. The content of ascorbic acid decreased with maturation in the green lettuce but it was not affected by maturity in the red lettuce. This shows that there are no obvious signs of leaf senescence with age and the differences in pigments and antioxidants show no relation to the fresh-cut shelf life and thus cannot explain the effect of plant age on senescence of the wounded tissue. The net photosynthesis rate and carbohydrate reserves in the red lettuce were about half of that in the green lettuce but the shelf-life of both genotypes was similar. The net photosynthesis rate was not influenced by plant maturity in the green lettuce, whereas it decreased with maturation in the red lettuce. A decrease in sucrose and starch, and therefore the total content of carbohydrates with aging was observed in both genotypes. This effect was more pronounced in the red than in the green lettuce. There was no apparent relationship between the absolute levels of the total carbohydrates and the shelf-life of the fresh-cut product showing that carbohydrate reserves in itself cannot explain the effect of plant age on senescence of the wounded tissue. The leaves from older plants apparently have a reduced capability to cope with the stress from wounding. No simple one to one relationship emerged between any of the measured nutritional parameters, their change during maturation and the eventual shelf-life of the fresh-cut produce.

QTL Detection for Grain Water Relations and Genetic Correlations withGrain Matter Accumulation at Four Stages after Pollination in Maize

Abstract: Grain water relations were closely correlated with matter accumulation during grain development. In this study, QTL mapping for Grain Water Content (GWC) at four stages after pollination and Grain Dehydration Rate (GDR) during six intervals were done using 258 Recombinant Inbred Lines (RIL). Meta-QTL (mQTL) was revealed by meta-analysis using Bio Mercator for both traits herein and together with seven traits related with grain matter accumulation in our previous research. Among 40 QTL detected for GWC and 35 QTL for GDR, 45 QTL were stage/period specific. QTL on chromosome 5 could be considered as full-stage QTL. Eight of 11 mQTL included QTL for both traits. Grain matter traits were positively correlated with GWC, but negatively correlated with GDR in most cases. Low coincidences in QTL position and opposite allelic effects for two kinds of traits suggested that their simultaneous improvement might be realized. Selection for low grain moisture could be focused on QTL at bins 1.07- 1.08, 2.08, 4.03-4.04 and 5.03-5.04, while it should be followed to QTL at bins 7.02-7.03, 1.03-1.04 and 10.05-10.06 for high grain weight. However, this should be proved through practical selection, and the related marker intervals needed to be narrowed down in further research.

Transcriptome Analysis of Tessellated and Green Leaves in Paphiopedilum Orchids Using Illumina Paired-End Sequencing and Discovery SimpleSequence Repeat Markers

Abstract: Transciptome analysis based on next generation sequencing allows quantitative comparisons of gene expression across diverse species. Using Illumina sequencing, we generated a total of 35.7 and 30.1 million paired-end reads with lengths of 100 bp from Paphiopedilum concolor tessellated leaves and Paphiopedilum hirsutissimum green leaves, respectively. De novo assembly yielded 68,602 and 54,273 unigenes with average lengths of 844 and 874 bp for each species leaves, respectively. Based on BLAST searches with known protein sequences, 46.6% unigenes from P. concolor and 48.6% unigenes from P. hirsutissimum were annotated. Gene ontology, cluster of orthologous groups and kyoto encyclopedia of genes and genomes annotations revealed that the functions of the transcripts from the two Paphiopedilum species leaves covered a similarly broad set of molecular functions, biological processes and metabolic pathways. Gene expression profiles analyses between the two Paphiopedilum species leaves revealed that a total of 1,544 genes were obviously differentially expressed. To confirm the differential expression results, the expression profiles of 8 selected genes were analyzed by quantitative real-time PCR. Both transcript differences analysis and leaf internal morphology observation between the two Paphiopedilum species leaves demonstrated that chloroplast, cytoplasm, thylakoid membrane, extracellular region, and nucleus related genes probably played crucial roles in the two Paphiopedilum species leaves formation during evolutional processes. Finally, 8,523 potential EST-SSRs were identified, and 7,864 primer pairs for 6,210 SSRs were obtained. This study provides a valuable clue to understand the mechanisms of Paphiopedilum leaves formation during evolutional adaptation, and supplies us with a large leaf sequence resource for novel gene discovery and marker-assisted studies in Paphiopedilum plants.

Natural Antioxidants and their Role against Human Cancer

Abstract: Volume 2 • Issue 2 • 1000e125 J Plant Biochem Physiol ISSN: 2329-9029 JPBP, an open access journal Plant natural products are gaining more attention during the last decade as nature cure for human cancer, which is the main reason for human death in all over the world, especially with a growing number of aging populations in developed and developing countries. 41% of the developed antitumor agents in 2012 were either natural products or modified natural products [1]. Plant natural products have been correlated with antibacterial and antioxidant activities [2,3]. Antioxidants are the major plant products that play a role as anticancer agents [4], by acting as reducing agents, hydrogen donators, and singlet oxygen quenchers that suppress the naturally produced free radicals and delaying oxidative reactions such as lipid oxidation [5,6]. Further, antioxidant studies have suggested associations between the consumption of phenolic-rich food and beverage and reduced oxidative stress-related diseases [7].

Universal Molecular Markers for Plant Breeding and Genetics Analysis

Abstract: information from an unknown but related genome. Indeed, Wu and co-workers have developed universal primers in solanaceous species with single-copy orthologs (COSII), and successfully applied COSII to the study of syntenic relationships among tomato, eggplant, pepper, and Nicotiana [18-21]. These results have a great significance for the analysis of those genomes where marker and sequence density is scarce or lacking but is available in case of a related taxon [22-24]. Thus, if one were to consider a crop plant for molecular breeding work, say for instance, the cluster bean (Cyamopsis tetragonoloba) or any other leguminous crops, where such data are scanty or altogether lacking, it is now possible to deploy markers and genome sequence derived orthologs from the sequenced leguminous taxon closest in relation to these crops with no or little genome sequence data to achieve an unprecedented level of rich marker density in a much shorter period of time than that it would otherwise have taken to develop de novo the entire set of marker data. This possibility of developing markers universally based on markers and sequences of orthologs of a related sequenced genome is exciting in its potential application to even trees which have always been less studied for molecular breeding on account of their long generation times. Several papers have highlighted the existence of gene and marker synteny across taxa. The important rationale here is the derivation of present day genomes from an ancestral one during the course of evolution. That this has happened is the basis for the several phylogenetic and phylogenomic studies reported so far in plants. Tracing the evolutionary history of the genome is in fact based on the synteny / co linearity of genes and gene orders. It is because of the expectation of a synteny that it also becomes easy to identify deviations from the synteny that occasionally occurs due to transposition, mutations recombination events so that certain portions of the genome

The SNARE Proteins (In Plants) Beyond the Nobel Prize

Abstract: SNAREs (N-ethylmaleimide-sensitive factor adaptor protein receptors) are small polypeptides characterized by a specific domain called SNARE motif. This can form a coiled-coil structure and interacts with other SNARE motifs via hetero-oligomeric interactions to form highly stable protein-protein interactions. The derived complex is called SNARE-complex and allows membrane fusion. SNAREs also interact with several proteins acting as regulators of this complex formation. Their indubitable importance was certified by the Nobel Prize 2013 for Medicine, awarded to the scientist who clarified the way they interact, James E. Rothman. Nobel Prize was shared with the other two scientists contributing to the description of vesicle traffic, Randy W. Schekman, and Thomas C. Sudhof, but SNAREs certainly have central role in the determination of traffic specificity. Recently the model that won the Nobel was enormously enriched by further discoveries, about SNAREs in particular. In fact SNAREs stoichiometry reveals that they are more abundant than required for membrane traffic.

28-Homobrassinolide-Induced Exaggerated Growth, Biochemical MolecularAspects of Brassica Juncea L. RLM-619 Seedlings under High TemperatureStress

Abstract: The present study was pertaining to study the mechanism and signaling of BRs under high temperature stress in Brassica juncea L. plants. Results advised that high temperature stress reduced the shoot length, root length, fresh weight of the plants but 28-homobrassinosteroids (28-homoBL) treatment reduced the toxic effect of high temperature stress by improving the same of B. juncea L. plants. To ascertain these free radical scavenging enzymes (superoxide dismutase (SOD), Catalase (CAT), Peroxidase (POD), Ascorbate peroxidase (APOX), Polyphenol oxidase (PPO) and Indole acetic acid oxidase (IAAO) and lipid oxidation (MDA) were assayed along with photosynthetic pigments, total carbohydrates, reducing sugars and non-reducing sugars. All studied scavenging enzymes activities were ameliorated by the homoBL treatments. The pigments decreased under temperature stress were also protected by homoBL treatments. Proteins profiling by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDSPAGE) were also studied to know the behavior of proteins under temperature stress as well as with the treatment of homoBL. Protein bands disappeared in temperature stress while in the presence of homoBL treatment existing proteins displayed more accumulation leading to the appearance of new bands. Native-PAGE of SOD, CAT and POD suggested the presence of in isoenzymic forms in cells. Application of different concentration of homoBL increased intensities of these isoenzymes under temperature and normal condition as compared to control untreated seedlings. The gene expression of SOD and CAT also suggested that synthesis these enzymes were decreased under high temperature stress but ameliorated with the treatment of homoBL. Present study demonstrated that 28-homoBL have stress-ameliorative properties in B. juncea seedlings exposed to high temperature stress by improving seedling growth and enhancing protein content as well as activities of SOD, CAT, APOX, PPO and IAA Oxidase. Further, it was suggested by decreasing the MDA content after the treatments of 28-homoBL. This study demonstrate the culmination of BR’s as an anti-stressor for protection of plant exposed to high temperature stress but extensive studies are still needed to know the various aspects related to stress and role of brassinosteroids in regulating them at molecular and signaling level.

Dynamic Element Concentrations and Similar Proteome of the Rhizome and Root of Miscanthus X Gigantheus

Abstract: In the perennial biomass grass Miscanthus, the rhizome, a below-ground storage organ, is important for its nutrient-efficiency. Here, macro- and microelements in the rhizome and other organs were measured in different seasons. All nutrient concentrations were generally low, indicating high nutrient efficiency to build up biomass, and differed markedly between the organs, including root and rhizome. Active translocation from the shoots increased the rhizome N and P concentrations. After the growth period, most elements remained constant in the shoot. Although the rhizome and the root massively differed in their elemental concentrations, morphology and structure, their proteome was highly similar when analyzed by 2D-gel analysis. Only ~10% of the detected proteins differed, with stress-related proteins found more abundant in the rhizome and glycolysis-related proteins higher expressed in the root. The highly similar proteome of rhizomes and roots suggests major functional similarities in sub-surface organs, despite clear morphological, structural and nutritional differences.

Antioxidant Activity of Pulse Hydrocolloids: Classical Screening MethodsDepending on Water Soluble Phenolic Antioxidants Need Revision toMeasure True Antioxidant Potential of Pulses

Abstract: The aim of this study is to show the presence of considerable amounts of antioxidants bound on pulse hydrocolloids. For this purpose, 6 lentil and 4 chickpea cultivars were tested for their free radical scavenging based antioxidant capacities in water soluble extracts and hydrocolloid extracts. The results clearly showed that the antioxidant potential of pulses based on hydrocolloid extracts accounts for 28 to 89% of those based on soluble phenolic antioxidants. Moreover, the antioxidant activity measurements in hydrocolloid extracts help much more than those in water extracts to determine differences among the antioxidant potentials of pulse cultivars. Extensive screening studies have been conducted by plant breeders to understand the importance of different phenotypic and genetic factors as well as the growth conditions on antioxidant status of the plants. This work clearly showed that not only water extracts, but also hydrocollid extracts should be considered to conduct realistic screening studies.

The Physiological Characteristics, Expression of Oxidosqualene CyclaseGenes and Accumulation of Triterpenoids in White Birch (Betula platyphyllasuk) Saplings by Sa and Meja Treatment

Abstract: The pentacyclic triterpenoids from birch (Betula platyphylla suk) have broad pharmacological activities and can be potentially used for the development of anti-cancer and anti-AIDS drugs. In this study, we explored the effects of spraying 3-year old white birch with different concentration of methyl jasmonate (MeJA) and salicylic acid (SA) on the expression of key genes in triterpenoid biosynthesis pathways and on the accumulation and physiological characteristics of triterpenoids in birch saplings. The results show that, spraying different concentration of MeJA and SA could obviously promote accumulation of total triterpenoids in 3-year old white birch. The triterpenoid content in the stem bark was significantly increased after 1d of treatment with 1 mmol·L-1 MeJA (MJ2) and after 14 d of treatment with 5 mmol·L-1 SA(SA1), triterpenoid contents of MJ2 and SA1 reaching 81.86 mg/g and 91.40 mg/g, increased by 46.11% and by 45.07% compare control(CK), respectively. In addition, MeJA and SA treatment increased the contents of chlorophyll a and b, antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), and photosynthetic performance, and affected the content of soluble sugar and soluble protein in birch leaf. Fluorescence quantitative polymerase chain reaction (qPCR) results showed that MeJA and SA treatment deferentially enhanced the expression of key genes farnesyl diphosphate synthase (FPS), cycloartenol synthase (BPX and BPX2), lupeol synthase (BPW) and beta-amyrin synthase (BPY) in triterpenoid synthesis pathway in birch bark and leaves. The results showed that MeJA and SA induced triterpenoid synthesis of birch plant is closely related with not only the expression of key genes of triterpenoid synthesis pathway but also photosynthesis, anti-stress response and physiological indexes, suggesting regulation of triterpenoid synthesis of birch by MeJA and SA may involve in more complex mechanisms at physiological and molecular level.

Comparative Genomic View of The Inositol-1,4,5-TrisphosphateReceptor in Plants

Abstract: Terrestrial plants lack inositol-1,4,5-trisphosphate (IP3) receptor regulating transient Ca2+ increase to activate cellular Ca2+-dependent physiological events. To understand an evolutional route of the loss of the IP3 receptor gene, conservation of the IP3 receptor gene in algae was examined in silico based on the accumulating information of genomes and expression sequence tags. Results clearly demonstrated that the lack of the gene was observed in Rhodophyta, Chlorophyta except for Volvocales and Streptophyta. It was therefore hypothesized that the plant IP3 receptor gene was eliminated from the genome at multiple occasions; after divergence of Chlorophyta and Rhodophyta and of Chlorophyta and Charophyta.

Composite Insecticides Effects on Defensive and Nutritious Compounds inCotton Leaves

Abstract: As cotton plant is treated with insecticides especially with pyrethroids, aphids and mites often increase Understanding the effects of insecticide preparations on sugars and soluble proteins which are expected to be food niche and defensive compounds will help to predict the probable side-effects of them The effects of five composite insecticide preparations on soluble proteins, total and reducing sugars, terpenoid aldehydes, and chitinase and peroxidase activities of the leaves of one Cotton cultivar were studied Field experiments were carried in cotton fields of Tokshin district of Turpan region (Xinjiang Autonomous Region, China) The effects of insecticide preparations were reversely correlated with the activities of chitinase and peroxidase enzymes The gained results showed that, after treatment with insecticide preparations, the quantity of soluble proteins increased whereas the activity of the PR proteins was lower than control leaves Terpenoid aldehydes having anti-feedant properties also increased All composite insecticides lowered the quantity of reducing sugars However nonlinear changes were observed with the total sugars in cotton leaves after treatment

Fine Scale Genetic Mapping of the TT9 Locus of Arabidopsis thaliana

Abstract: Numerous transparent testa (tt) or tannin deficient seed (tds) mutants have been isolated in the model plant Arabidopsis thaliana These mutants are characterized by a reduction or lack of proanthocyanidins in the testa, resulting in pale brown or yellow seeds Among the tt mutants, all the corresponding genes have been cloned except for tt9 and 13 As a first step towards determining the identity of the tt9 locus, fine scale genetic mapping was carried out using a mapping population resulting from a cross between tt9 plants in the Landsberg erecta (Ler) ecotype background with wild-type Columbia (Col) plants Several simple sequence length polymorphism markers were developed, and a large population of plants was analyzed Extensive analysis of this mapping population suggests the tt9 locus is found in a 140,000 base pair region on chromosome three According to the TAIR 10 genome release for Arabidopsis, there are thirty-four genes in this region Several approaches were utilized in an effort to identify which of these genes is the TT9 locus, including sequencing of candidate genes, comparison of steady-state mRNA levels of candidate genes in the parental line and the tt9 mutant, and analysis of T-DNA tagged lines However, the TT9 locus has not yet been identified based on any of these analyses This suggests that the mutation of interest may lie in a non-coding region of a candidate gene, in a micro-RNA, or other as-yet-unannotated gene in the mapping interval The fine-scale mapping described here will facilitate future efforts to identify a definitive causative mutation in this elusive locus, for example, by whole genome sequencing

Characterization of a Glycan Exo-Hydrolase that Shows a Biphasic Expressionin the Course of an In Vitro Culture of Photoautotrophic Oxybasis rubraCells

Abstract: Like plant leaves, suspension cultures of photoautotrophic Oxybasis rubra Fuentes-Bazan (syn. Chenopodium rubrum L.) cells pass through distinct developmental phases when grown under CO2 as the sole carbon source: an initial cell division phase of 4 weeks, a stationary phase of another 4 weeks and an aging phase (3-4 weeks) when the cell senesce and finally die. These phases are reflected by differential gene expression. A gene that was strongly expressed in the course of the stationary phase but much lesser during the exponential growth phase of the cell culture was isolated from a cDNA-library of stationary cells and completed by 5’-RACE. From homology analysis, the gene was tentatively identified as glycan exo-hydrolase (Oxybasis rubra glycan exo-hydrolase, OrGEH). Heterologous expression in E. coli yielded a protein with a preference to hydrolyze the s-D-galactopyranoside, s-D-fucopyranoside and s-D-glucopyranoside of the corresponding artificial p-nitrophenyl substrates. Possible function of the protein in cell-wall metabolism was confirmed by extracellular localization of the GFP-fusion protein in transformed Nicotiana benthamiana leaves, by an N-terminal signal sequence for the secretory pathway and by the positive response of gene expression to auxin. Suspension cultured OrGEH RNAi-lines showed not only strongly reduced cell division activity but also lack of the stationary phase during which the cells usually double their biomass by extension growth. Although the natural substrate of the protein is not known we propose a function of OrGEH in the processing of cell wall components during cell division and cell extension growth.

SNP Array' A Powerful Platform to Accelerate Genetic Studies andBreeding

Abstract: Volume 2 • Issue 1 • 1000e119 J Plant Biochem Physiol ISSN: 2329-9029 JPBP, an open access journal Lots of traits in cereals are quantitatively inherited and controlled by multiple genes. In general, these kinds of traits have wide natural variations. Linkage analysis and Linkage Disequilibrium (LD) analysis are the main approaches to discover and locate target genes underlying the traits. Several kinds of molecular markers such as restriction fragment length polymorphism and simple sequence repeats have been used for genetic mapping. But these markers are not suitable for developing a high-density genetic map. Due to its abundance and uniform distribution throughout a genome, and single nucleotide polymorphisms (SNPs) are considered to be the most desirable molecular markers and have been demonstrated to be efficient markers for developing high-density genome scan [1,2]. Wholegenome sequencing and oligonucleotide microarray are the two main strategies used to create SNP markers. Because of its economic cost, SNP array, a high-throughput genome scan, is an important tool for genetic studies and breeding applications. A SNP array designed with a very huge number of SNPs evenly spaced genetically across genomes has been developed in maize, rice and wheat [3-5]. But currently, they are not widely used for genetic analysis. The most important factor limited the application of SNP array is its comparative high cost to researchers. Meanwhile, the researchers also focus on how many SNPs are positioned on the array and when low-, mediumor high-density SNP arrays are used.

Rhizospheric Bioweapons for Tuber Yield Enhancement in ChlorophytumBorivilianum against Meloidogyne Incognita Infestation

Abstract: Chlorophytum borivilianum Santapau and Fernandez (Liliaceae) is a therapeutically important tuber crop, vulnerable to Meloidogyne incognita (Kofoid and White) Chitwood infestation. Therefore, the present study was designed to explore the efficacy of rhizospheric microbes viz. Bacillus megaterium, Pseudomonas fluorescens, Glomus intraradices, and Trichoderma harzianum CIMAP-RPN01, both singly and in combinations, for the successful management of M. incognita as well as to determine the comparative impact of different microbes on the growth/yield of C. borivilianum. Maximum reduction in M. incognita infestation was recorded in dual treatment viz. T. harzianum + P. fluoresces followed by that of T. harzianum + B. megaterium. This study proves the beneficial effects of rhizospheric microbes in galvanizing the quality and quantity yields of this medicinally important crop.

Maturity Response of Ratoon Cane (Saccharium officinarium L.) as Affected by Pre-Harvest Cultural Practices in the Tropical Area of Ethiopia

Abstract: To attain maximum sucrose accumulation,optimum maturity recommendation was needed depending on the soil type, cultivar type and environmental factors. To this end, an experiment was conducted to determine maturity response of ratoon cane (Saccharium officinarium L.) as affected by pre-harvest cultural practices. The sugarcane variety B52-298 was used as a test crop. The two experimental factors were four drying off periods (25, 45, 65 and 85 days) and four harvest ages (360, 390, 420 and 450days) and their factorial combination was tested using randomized complete block design with three replications. Analysis of variance (ANOVA) showed that Drying off period significantly influenced maturity testing factors (P<0.001). Hand refractometer brix% of all stalk parts, were significantly increased when the level of drying off period was increased with a peak at 65 days. In contrast, soil moisture content, sheath moisture content, were reduced with increasing drying off period. Effect of harvest age also significantly influenced the sheath moisture content and hand referactometer brix (P<0.001). Increase in harvest age, significantly increased hand refractometer brix% of all stalk parts. Adjusting the drying off period to 65 days and harvest age to 450 days for variety B52-298 under the tested soil condition for ratoon crop is recommended as best maturity with optimum sucrose accumulation and is recommend for harvest.

K. daigremontiana as a Model Plant for the Study of Auxin Effects in PlantMorphology

Abstract: A large number of studies have been conducted in order to understand the mechanisms by which shoots, plantlets and vegetative propagules are produced. According to the first studies reported by Yarbrough [2, 3], in the fern species Camptosorus rhizophyllus (which has two different kinds of leaves), shoots are produced at the tip of long acuminate leaves, while in the species Tolmiea menziesii shoots are originated in a notch near the junction of the petiole and the leaf blade; in both cases, the shoots are produced from meristematic tissue and once they are mature are naturally detached from the leaf and fall to the ground originating a new plant. Also, in the orchid Malaxis paludosa, cells at the tip of mature leaves have an intense meristematic activity which originates embryo-like structures that once the mature leaf is wilted the small shoot detaches originating a new plantlet [4]. This phenomenon has been widely studied in plants of the Crassulaceae family, mainly in the genus Kalanchoe. According to the capacity to asexually produce such plants, species of this genus have been classified in four categories: a) plants which do not produce plantlets (K. marmorata, K. rhombopilosa, K. tomentosa and K. thyrsiflora), b) plants that spontaneously produce plantlets (K. daigremontiana), c) plants that produce plantlets by the action of an environmental stress (K. pinnata, K. fedstchenkoi, K. strepthantha, K prolifera and K. crenata) and d) plants that produce spontaneously plantlets by the action of stress and/or (K.

Defoliation Influences Starch Granule Distribution and Structure in Medicagosativa L. Taproots as Revealed by SEM and TEM

Abstract: Taproots of mature Medicago sativa L. plants store abundant starch that cycles with defoliation. Starch is a key component that provides energy for regrowth of alfalfa plants post defoliation (PD). Starch is located mostly in the parenchyma cells of wood medullary ray and bark tissues. The objectives of this study were to investigate the influence of defoliation on the distribution of starch granules in cells within bark and wood tissues and changes to starch granule structure. Plants were grown to maturity in the greenhouse, defoliated, and root samples were analyzed by SEM from plants sampled on different days PD. TEM was used to study the structure of starch granules on Days 0, 12, and 28 PD and 12 day non-defoliated plants. A one-way ANOVA revealed a significant difference in the distribution of starch granules between the two tissues over the 35 day PD interval. The distribution of starch granules declined significantly on Days 10 and 12 when compared with Days 1 to 8 PD. Starch granules increased between Days 14 and 35 in bark cells, and in medullary ray cells the starch grain increase between Days 14 and 35 showed variations. There was a preponderance of smooth, clearly defined, and continuous surface starch granules in cells on Day 28 PD. In contrast, the surfaces of most starch granules appeared rough, irregular, and had various size crevices on Day 12 PD and non-defoliated plants. On rare occasions, intact amyloplasts were seen during times of net starch synthesis, but never during times of net starch degradation. This study revealed the post defoliation timeline when the lowest number of starch granules and major structural changes in amyloplasts occur. These results indicate when to target genes regulating reserve starch degradation in alfalfa with potential to contribute to alfalfa productivity.

Medicago sativa L. β-Amylase Core Promoter has Motifs in Common with Arabidopsis Key Starch Degradation Genes

Abstract: β-amylase is an enzyme involved in the degradation of transitory starch in photosynthetic tissues of plants and is expressed in high levels in the roots of Medicago sativa L. How the β -amylase gene MsBAM1 is regulated in the roots is not clear. The aims of this study were to: isolate the core promoter of MsBAM1, decipher motifs in silico that are associated with the elevated root specific response, and to find common motifs among core promoters of important starch degradation genes in Medicago sativa MsBAM1 and Arabidopsis (AtGWD, AtPWD, AtMEX1, AtBAM 1 & 3, and AtISA3). Primers were designed from homologous β-amylase genes and used in PCR with M. sativa gDNA. Gel purified PCR band(s) were sequenced, verified and annotated. The starch genes and equal numbers of Arabidopsis non-starch genes promoters were analyzed by the transcription factor binding site database (PLACE). Motif frequencies between starch and non-starch genes were statistically analyzed. A TATA-box motif was identified in the MsBAM1 core promoter. Chi-square and Fisher’s exact test analyses revealed significance of the frequency of the motifs ROOTMOTIFTAPOX1 (RMP1) and GATABOX (GATA) between starch and non-starch genes, but not the DOF motif. The RMP1 and GATA motifs were detected in MsBAM1 and in all the Arabidopsis starch degradation genes but only in a few of the non-starch genes. However, the DOF motif was found in all starch and non-starch degradation genes in similar frequencies. These motifs may work in combination with other known cis-regulatory elements to confer root-enhanced expression in alfalfa roots and co-transcriptional regulation in the starch degradation pathway

Decrease of Auxin Binding Protein 1 Gene Expression Alters ShootDevelopment in Ramie

Abstract: AUXIN BINDING PROTEIN1 (ABP1) has long been proposed as a candidate of auxin receptor to mediate auxin action in plants. It is essential for plant organ development. The function of ABP1 in the development of ramie (Boehmeria nivea L.) remains unclear. Here, we examined the role of the ABP1 gene in the development of shoot in ramie, especially in leaf venation ontogeny, by transforming ABP1 antisense construct into the plants. We showed that ABP1 expression was decreased in ABP1 antisense transgenic plantlets. The decrease of ABP1 expression led to defects in plant growth including dwarf plant, and decreased apical dominance in the intact plant. In addition, ABP1 antisense lines exhibited a serious retard of leaf development involving small and twisted leaves, sparse trichome, and a decreased cell expansion. Moreover, the decreased ABP1 expression repressed the development of leaf venation. ABP1 antisense lines developed an incomplete leaf venation, which became smaller and lacked in some leaf tissues. Though the cell arrangement was normal in midrib and lateral vein, cell size was decrease and some cell layers were missing in midrib. The abnormal phenotype of leaf venation was attributed to the decreases in cell number and size. Our data support that ABP1 is necessary for shoot growth in ramie. More importantly, it plays a key role for the development of ramie leaf venation by regulating both cell expansion and division.

Potassium Fertilization - An Effective Mitigator of Unused Nitrogen inForage Sorghum

Abstract: Forages tend to accumulate elevated levels of nitrate when fields are heavily fertilized with nitrogenous fertilizers or are environmentally stressed due to drought, cold, frost, hail, etc. Elevated levels of nitrate have detrimental effects on animal health and are regarded as a causative factor for several mass cattle-death incidents. It was observed that nitrate concentration in Sorghum bicolor L. obtained from local fields of Uttar Pradesh (Ghaziabad and Meerut) and Haryana (Gurgaon and Faridabad) exceeded the safe limit (2500 mg of nitrate kg-1 of fresh wt.) in a significant number of samples (31.7%) studied. Given this, the investigation was conducted in earthen pots to determine nitrate contents in 16 genotypes of S. bicolor L. A significant difference in nitrate content was observed among genotypes, many of which accumulated nitrate to toxic levels. POP-52 (V9), a high nitrate reductase (HNR) genotype and EB-15 (V7), a low nitrate reductase (LNR) genotype of sorghum were selected to study the effect of potassium (K) application on nitrate accumulation in specially designed PVC-drums. The minimum nitrate concentration (V9= 816.6 mg/kg fresh wt. and V7= 2691.8 mg/kg fresh wt.), coupled with maximum NR activity (V9= 9.916 μmol NO2 –1 h–1 g–1 fresh wt. and V7= 5.018 μmol NO2 –1 h–1 g–1 fresh wt.) were observed in 60 day old K60 treated plants. K application reduced the nitrate concentration by 35.24% in V9 and by 25.54% in V7 genotypes by increasing nitrate reductase (NR) activity by 86.23 % in V9 and lesser increase of 32.07% in V7 genotype of sorghum at 30 days. A two- fold (approx.) decrease in nitrate concentration was observed at K60 in both genotypes from 30 to 60-days-after-sowing. K application also reduced considerably the nitrate in the leachate indicating that K is effective in mitigating nitrate pollution in plants and soil. The data emphasizes the importance of K in increasing the nitrogen use efficiency and of balanced fertilization in combating the nitrate-related implications on human beings, animals and environment.