Scientific Program

Conference Series Ltd invites all the participants across the globe to attend Global Summit on Plant Science San Antonio, USA.

Day 2 :

  • Track 4: Plant Pathology and Weed Science
    Track 5: Medicinal Plants
    Track 6: Plant Morphology and Metabolism
    Track 11: Plant Genetics and Epigenetics
Speaker
Biography:

Nabil Killiny is Assistant Professor in the Department of Entomology and Nematology & Citrus Research and Education Center (CREC), Institute of Food and Agriculture Sciences, University of Florida. The French Society of Phytopathology, awarded with student fellow travel Award, 2004 Synergistic Activities: Ad Hoc Manuscript Review: Plant Pathology, Phytopathology, Journal of Bacteriology, PLoS One, Journal of Insect Physiology, Molecular Plant-Microbe Interactions, Current Microbiology, Electron Microscope Techniques, Biomedicine and Biotechnology, European Journal of Plant Pathology.

Abstract:

Virus-based vectors as regular laboratory tools to express foreign genes in plants are often developed for short-term laboratory experiments in plants. They are also used to knockdown the expression of plant endogenous genes. It is challenging to develop vectors that continuously express foreign genes for long-term. However, the newly developed vectors open up opportunities to create plants that show disease resistance or attract insect predators permanently. Citrus currently is threatened with Huanglongbing (HLB), a major disease that caused by Gram-negative bacterium Candidatus Liberibacter asiaticus and transmitted by the Asian citrus psyllid, Diaphorina citri. A developed Citrus tristeza virus (CTV)-based vector that shows stability is considered viable for use in the field to control HLB. Many potential uses for this vector have been addressed. We used this vector to disturb quorum-sensing resulting in interrupting the bacterial growth within the plant and the transmission by the insect. Interestingly, we can also use CTV-based vector to mitigate the insect though RNA interference (RNAi). CTV-vector could be engineered with truncated genes of D. citri to induce gene silencing causing mortality or malformation. Additionally, using CTV-vector to knockdown citrus endogenous genes such as phytoene desaturase (PDS) or delta amino levulinic acid dehydratase (-ALAd), allowed us to bioengineer psyllid attractant plants that could be used as trapping borders in Citrus groves. CTV-based vector would be a powerful tool for fast-track screening of sequences for RNAi, antibacterial peptides and understanding the pathogenicity of Ca. Liberibacter asiaticus to provide sustainable solutions for the control of HLB.

Ajith Anand

DuPont Pioneer, USA

Title: Gene targeting approaches in corn
Speaker
Biography:

Ajith Anand completed his PhD under Professor M.S. Swaminathan, from Madras University and postdoctoral studies in the Departments of Biochemistry, Kansas State University and the Plant Biology Division, Samuel Roberts Noble Foundation, Oklahoma. He is currently employed with DuPont Pioneer, researching on enabling technologies for precision genome modification and monocot transformation. He has published more than 30 papers in refereed journals, authored five book chapters, organized and served in professional conferences, routinely presented research papers in International conferences and has filed patents. Dr. Anand is also a member of several societies and serves in the editorial board of repute journals.

Abstract:

Even though transgenic plant production in the industry is routine, the current technology relies on methods resulting in integration of the transgenes in random sites in the genome, causing unpredictable and instable gene expression. In contrast to randomly generated traits, precision genome modification/integration presents distinct advantages by producing well-defined events, reduced cost for trait introgression and potentially shortened timelines to market. Targeted integration of traits into predefined genetic loci and targeted genome modification presents the opportunity for precision genome engineering, which likely could deliver more stable and predictable biotech traits. Rapid developments in the field of gene targeting specifically, Site-Specific Recombination (SSR) and Homologous Recombination (HR), and the potential of the technology to revolutionize genomics and plant biotechnology has resulted in its broad adoption. Both this technology has been widely applied in animals, but with limited success in plants. I will discuss the significant breakthroughs and refinements made in the application of SSR and HR for gene targeting in corn.

Speaker
Biography:

Prof. Ilan Chet completed his Ph.D. in microbiology at the Faculty of Agriculture of the Hebrew University of Jerusalem. He has published more than 390 articles, edited five books and holds 38 patents. Prof. Chet served as Dean of the Faculty of Agriculture and Vice President of the Hebrew University and was President of the Weizmann Institute of Science. He was visiting professor at Harvard, Colorado State, Cornell and Rutgers Universities. Prof. Chet was awarded with the Max-Planck, the Israel Prize, the Wolf Prize and more. He is nowadays Deputy Secretary General of the Secretariat of the Union for the Mediterranean.

Abstract:

Triohoderma is a fungus acting as a biocontrol agent. Biological control, the use of specific organisms that interfere with plant pathogens, is a nature-friendly, ecological approach to overcome the problems caused by hazardous chemical methods in plant protection. Mycoparasitism is an efficient biocontrol mechanism evolving extracellular chitinases, ß-1-3 glucanases and proteases. Cloning these genes into plants can induce their resistance to diseases. Moreover, these fungi can induce systemic resistance (ISR) to diseases by priming the expression of several plant defense related genes which enables Trichoderma- treated plants to be more resistant to subsequent pathogen infection. Root colonization by Trichoderma trains results in massive changes in plant metabolism leading to accumulation of antimicrobial compounds in the whole plant. Recent studies demonstrate that Trichoderma can also include resistance to plants in the presence of various abiotic stresses like drought and salinity. Understanding the molecular basis of the diverse modes of action of these versatile beneficial fungi is a central goal of our research.

Speaker
Biography:

Nurul Faridi has completed his PhD at the University of Cambridge, England, UK, 1988 and worked at the International Rice Research Institute and Intl. Maize and Wheat Research Institute, Mexico from 1989 to 1994, and then worked in the Department of Soil & Crop Sciences, Texas A&M University until 2003 before joining with the USDA Forest Service. He has been working in conventional and molecular plant cytogenetics for the last 25 years and published about 70 papers in reputed journals.

Abstract:

The American chestnut (Castanea dentata, 2n = 2x = 24), once known as the “King of the Appalachian Forest”, has been nearly decimated by chestnut blight caused by a fungal pathogen (Cryphonectria parasitica) that was accidentally imported on nursery stock from Asia in the late 1800s. Efforts are being made to transfer the blight resistance gene(s) from Chinese chestnut (C. mollissma) into American chestnut through backcross breeding and genetic engineering. A number of genetic linkage maps have been reported and are being utilized to accelerate the breeding program through marker-assisted selection. Additionally, the chestnut is being sequenced to enable gene discovery efforts aimed at facilitating molecular breeding and/or genetic engineering. It is generally understood that plant genomes contain large amounts of repetitive DNA, which interferes with efficient physical map construction and genome assembly. To aid the assembly process we are using 16 to 20 genetically and physically mapped BAC clones as probes from each of the 12 linkage groups (LGs) in fluorescence in situ hybridization (FISH). A full structural characterization of the LG_B chromosome of Chinese chestnut has been completed using 20 BAC clones, and all the BACs are found to be hybridized LG_B specific chromosome. The same analysis is being completed for LG_E to evaluate a long-standing hypothesis of a reciprocal translocation involving these chromosomes. In addition, we have assigned each of the 12 LGs to individual chromosomes of Chinese chestnut and a cyto-molecular map is being developed. The resultant map will be essential for completing the arrangement of the reference genome sequence and genes for chestnut. Details of our research results and further plans will be presented and discussed.

Russel J. Reiter

University of Texas Health Science Center, San Antonio

Title: Phytomelatonin: helping plants to survive and to thrive
Speaker
Biography:

Dr. Russel J. Reiter, Ph.D., is Professor in the Department of Cellular and Structure Biology at the University of Texas Health Science Center, San Antonio, Texas, USA, Dr. Reiter has received three honorary M.D. degrees and one honorary D.Sc. degree. He has received numerous awards for his research including the A. Ross McIntyre Gold Metal (USA), the US Senior Scientist Award (Germany), Lizoni Lincee Award (Italy), the Inaugural Aaron B. Lerner Pioneer Award (FASEB, USA), etc. His scientific publications have been cited in the scientific literature more than 83,000 times; his h-index is 140. Thomson’s Institute lists Dr. Reiter as one of the World’s Most Influential Scientific Minds-2014 and he is listed in the top 100 scientists in the world in terms of frequency of citation in the fields of Cell Biology and Biochemistry. He is the Editor-in-Chief of the Journal of Pineal Research (2013 impact factor = 7.81) and is or has been on the Editorial/Advisory Board of 26 other journals.

Abstract:

This presentation will summarize the advances that have been made in terms of the identified functions of melatonin in plants. Melatonin is an endogenously-produced molecule in all plant species that have been investigated. Its concentration in plant organs varies in different tissues, e.g., roots versus leaves, and with their developmental stage. As in animals, the pathway of melatonin synthesis in plants utilizes tryptophan as an essential precursor molecule. Melatonin synthesis is inducible in plants when they are exposed to abiotic stresses (extremes of temperature, toxins, increased soil salinity, drought, etc.) as well as to biotic stresses (fungal infection). Melatonin aids plants in terms of root growth, leaf morphology, chlorophyll preservation and fruit development. There is also evidence that exogenously-applied melatonin improves seed germination, plant growth and crop yield and its application to plant products post-harvest shows that melatonin advances fruit ripening and may improve food quality. Since melatonin was only discovered in plants two decades ago, there is still a great deal to learn about the functional significance of melatonin in plants. It is the hope of the author that the current summary will serve as a stimulus for scientists to join the endeavor of clarifying the function of this phylogenetically-ancient molecule in plants and particularly in reference to the mechanisms by which melatonin mediates its multiple actions.

Speaker
Biography:

Dr. Hanson completed his PhD in Plant Pathology from the University of Wisconsin at Madison in 1997 studying mechanisms of Geminivirus replication. Following post-doctoral work in molecular virology and viral oncology Dr. Hanson has held a faculty position in Molecular Plant Pathology at New Mexico State University. Dr. Hanson’s current research includes molecular and biotechnology work on viruses, fungi, prokaryotes, and nematodes affecting agricultural production

Abstract:

Viruses are pathogens that replicate much more rapidly than their hosts and often utilize error prone genome replication mechanisms which function to produce large populations of diverse progeny. This replication strategy has been proposed as a mechanism that enables rapid evolution and adaptation of viruses. Recent advances in deep sequencing methodologies have enabled the observation of viral populations as they replication during infection of individual hosts. Beet Curly top virus (BCTV) is a typical geminivirus that causes substantial disease on a wide variety of crops which has previously been shown to have error prone replication. In the described study we used deep sequencing to characterize the evolution of BCTV populations during plant infection. Ion Torrent sequencing was used to characterize BCTV progeny isolated from upper non-inoculated leaves of plants infected with an infectious clone of BCTV. Our results show that Ion Torrent sequencing is sufficiently accurate for detecting SNPs in populations of progeny virus but that the platform is not useful for detecting indels in viral progeny due to the high error rate of the platform. As expected, we found that SNPs did not accumulate in known functional domains necessary for viral replication. Our results also reveal several additional protected areas of the genome that likely represent novel and previously undescribed functional domains. Thus, deep sequencing is proving to be a versatile tool not only for estimating viral mutation rates but also for identifying functionally important regions of the genome that could be targetted in future studies examining viral replication.

Speaker
Biography:

Prof. Pushpa Agrawal completed her Ph. D. degree in the year 1984 from DAVV, Indore and postdoctoral studies from Miami University, USA and India Institute of Science Bangalore, India. She is Professor of Biotechnology and Dean, Post graduate studies in Biotech and Chemical Engineering at R. V. College of Engineering, Bangalore India. Many scholars are pursuing and completed Ph.D. under her guidance. She has presented over 100 research papers in conferences and published more than 40 papers in reputed journals. Prof. Pushpa has coauthored a book on biotechnology and chapters in 2 books and has been serving as managing editor and editorial board member of reputed journals. She has received various awards, honors and fellowships.

Abstract:

The use of chemical fertilizers and pesticides in commercial farming gives the threat of gradual aggravation of soil fertility. Use of agriculturally important microorganisms in different combinations is the only solution for restoration of soils. The bioformulations using humic acid with suitable biocontrol microorganisms namely, Pseudomonas fluorescens and Trichoderma harzianum have been developed to replace chemical fertilizers. Trichoderma harzianum is a major biocontrol agent against a wide range of phyto-pathogenic organism of economically important crops and extensively used in various parts of the world for plant disease management. These biocontrol agents are also known to degrade complex organic molecules into simpler molecules which help to improve soil fertility. Humic acid is an organic fertilizer which enhances the plant growth. The bioorganic formulations have been developed for controlling or suppressing of fungal diseases (Fusarium species) as well as to increase the plant growth and yield by increasing the soil fertility in an ecofriendly manner. The present report reveals an additive effect of microorganism with humic acid in both disease management and better plant growth. The results revealed that the Trichoderma harzianum with 2% humic acid based formulation was effective in inhibiting Fusarium growth invitro. The liquid bioformulations of humic acid along with the Pseudomonas fluorescens was tested and compared for viability as well as its inhibitory characteristics against Fusarium oxysporum, a fungus which cause wilt of tomato. Cell viability tests were carried out for the bioformulations by plate count method. Field studies were conducted for two crop varieties- radish and tomato. The results of in vivo and in vitro studies revealed better support for the viable cells as well as leafing and fruit characteristic in pots kept in field.

Hsin-Sheng Tsay

Chaoyang University of Technology,Taiwan

Title: Herb-based functional foods: from laboratories to the market
Speaker
Biography:

Prof. Tsay has more than 47 years research experience in Biotechnology of diverse crop plants including medicinal herbs. He has worked with Prof. Toshio Murashige, University of California, Riverside for his PhD on tobacco anther culture. For the last 13 years, he has been working at the Chaoyang University of Technology. There he has served as Dean, College of Science and Engineering; Director and Chair Professor of Graduate Institute of Biotechnology. Prof. Tsay has transferred more than 20 technologies pertaining to the functional foods for commercialization. He has published 265 research papers, has guided 23 PhDs and more than 100 Masters students. Prof. Tsay is on editorial boards of several international journals.

Abstract:

Consumption of alternative herbal folk medicines has had a tremendous increase in the last decade. A number of medicinal plants contain secondary metabolites which have many biologically active compounds. They are used against hepatic fibrosis and heart ischemia-reperfusion and proved to have anti-oxidant, anti-thrombosis, anti-hypertension, anti-stress, anti-virus, anti-tumor, anti-ulcer, anti-diabetic, anti-aging and anti-inflammatory activities. Non-availability of quality planting materials, low germination, slow plant growth, disease and pest incidence are major obstacles in the cultivation of conventional medicinal plants. In Taiwan, many economically important medicinal plants and herbs are produced using various explant materials by tissue culture technique to meet the increasing demand for their medicinal properties. Rapid multiplication through in vitro tissue culture can be advantageous for the continuous supply throughout the year. We have developed and standardized efficient, simple and rapid tissue culture protocols of many medicinal plants; optimized the conditions in the greenhouse and successfully established the regenerated plantlets in the field for the large scale commercial production. Availability of tissue culture protocol is the first step towards the development of the genetic transformation system.

Speaker
Biography:

Tatsuya Iwata has completed his Ph.D. at the age of 27 years from Kyoto University, Japan, and postdoctoral studies in Osaka Prefecture University and Nagoya Institute of Technology (NITech) in Japan. He is an assistant professor of NITech. He has engaged in the study of proteins which function by light absorption, especially, flavin-binding photoreceptors. Using various kinds of spectroscopic techniques, he is to reveal molecular mechanisms of those photoreceptors.

Abstract:

Various types of Flavin (FAD or FMN)-binding photoreceptors have been discovered in plants and photosynthetic microorganisms from the 1990s to the 2000s. They are named cryptochrome, LOV-domain-containing proteins (e.g. phototropin), and BLUF-domain-containing proteins (e.g. photoactivated adenylyl cyclase). They are classified by their structures and photoreactions. The photoreactions of crypto-chrome, LOV domain, and BLUF domain are reduction of flavin, flavin-cysteine adduct formation, and rearrangement of hydrogen-bonding network, respectively. Why are photoreactions different despite the identical pigments? Because flavin is surrounded by amino acid residues in a protein and amino acid residue(s) must lead to specific response. The purpose of my research is to identify components (amino acid residues) which lead to specific responses. Also, another purpose is to reveal structural changes for the signal transduction. Fourier transform infrared (FTIR) spectroscopy is a useful method to investigate how structural changes take place in the chromophore and apoprotein. Especially we focus on the hydrogen-bonding alteration of X−H groups (X = N, O, S), which are difficult to be obtained from the X-ray crystallographic analyses. Here, I will present our FTIR studies of flavin-binding photoreceptors, cryptochromes, LOV domain, and BLUF domain as well as photolyase. Photolyase is not a light-signaling protein but is similar as cryptochromes in amino acid alignments and tertiary structures. Photolyase is a DNA repair protein by use of near UV light. Unique protein structural changes obtained by the FTIR analysis will be discussed in relation to their functions.

Speaker
Biography:

Noura has completed her B.Sc and M.Sc. degree in (Agriculture Science /Plant production) 2001, 2007 in Salahaddin University – Erbil / College of Agriculture and published one paper in Mesopotamia Journal of Agriculture. She has joined assistant lecturer for 6 years in the same University and College and started her PhD project at Deakin University School of Life and Environmental Sciences, under the supervision of David Cahill and Jim Rookes in Geelong Waurn Ponds Campus

Abstract:

Ascorbic acid (AsA) participates in several aspects of plant growth, development, and productivity. Under optimum growth conditions, plants accumulate variable amounts of AsA in different organs. This project has examined, in Arabidopsis thaliana, the effect of AsA on growth and seed production through analysis of morphological and physiological parameters. The highest levels of AsA were found in flowering buds, premature siliques, leaves, and stems, respectively. In addition, the AsA level correlated positively with concentrations of indole acetic acid (IAA) but inversely with salicylic acid (SA) concentrations. Plants synthesise AsA through six different pathways and primarily through the galactose pathway. A mutant defective in production of GDP-mannose pyrophosphorylase, vtc1-1, had significantly reduced growth parameters such as root growth rate, root length, number of leaves, leaf area and plant height compared with vtc5-1 (defective in GDP-L-galactose phosphorylase production), dhar1 (defective in mitochondrial dehydroascorbate reductase) apx1 (defective in cytosolic ascorbate peroxidase) and the Col-0 wild type background. The role of AsA as a signal for the promotion of cell expansion was verified in embryonic root cap studies. In addition, AsA promoted cell division by rapid stimulation of differentiation in surrounding cells of the root quiescent centre in Col-0 compared with vtc1-1. A lack of AsA increased the intensity of hydrogen peroxide production in roots and also increased the number of secondary roots. Surprisingly the number of flowers and siliques per plant, the number of seeds per silique and seed size were also all affected in vtc1-1, which indicates a key role for AsA in plants.

Speaker
Biography:

I took my Licentiate Degree in Chemistry in 1973 at Ribeirão Preto School of Philosophy, Sciences and Literature, Department of Chemistry, University of São Paulo; my Doctorate Degree in Sciences - Emphasis in Organic Chemistry in 1978 at University of São Paulo, Institute of Chemistry, São Paulo, under the supervision of Dr. Otto R. Gottlieb. I carried out postdoctal research as a visiting scholar at University of Strathclyde, Glasgow, Scotland-U.K, under the guidance of Professor Peter G. Waterman in Feb./87 to Jun/89. My academic career started at São Carlos Federal University, Department of Chemistry, as an Assistant Professor in 1976; in 1978 I was promoted to Associate Professor and in 2005 to Full Professor.

Abstract:

A high performance liquid chromatography-ultraviolet (HPLC-UV) method was developed for quantifying hesperidin and rutin levels in leaves and stems of Citrus limonia, with a good linearity over a range of 1.0-80.0 and 1.0-100.0 µg mL-1 respectively, with r2 > 0.999 for all curves. The limits of detection (LOD) for both flavonoids were 0.6 and 0.5 µg mL-1, respectively, with quantification (LOQ) being 2.0 and 1.0 µg mL-1, respectively. The quantification method was applied to C. sinensis grafted onto C. limonia with and without CVC (citrus variegated chlorosis) symptoms after Xylella fastidiosa infection. The total content of rutin was low and practically constant in all analyses in comparison with hesperidin, which showed a significant increase in its amount in symptomatic leaves. Scanning electron microscopy studies on leaves with CVC symptoms showed vessel occlusion by biofilm, and a crystallized material was noted. Considering the difficulty in isolating these crystals for analysis, tissue sections were analyzed by matrixassisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) to confirm the presence of hesperidin at the site of infection. The images constructed from MS/MS data with a specific diagnostic fragment ion (m/z 483) also showed higher ion intensities for it in infected plants than in healthy ones, mainly in the vessel regions. These data suggest that hesperidin plays a role in the plant-pathogen interaction, probably as a phytoanticipin. In similar stem inoculating experiments we determined the population of X. fatidiosa in symptomatic plant, which shoed the highest bacterial population in the leaves, in stem and roots it was present but lower than in leaves. The chemical profile of scion and rootstock differed notably for absence in the second of flavonoid glycosides and low content of coumarins in the first. Thus, we also developed a rapid and sensitive HPLC method for quantitative determination of the coumarins xanthyletin and seselin in roots of C. sinensis grafted on C. limonia. The method showed a good linearity and was also applied to Citrus sinensis grafted onto C. limonia with and without CVC symptoms. The total content of seselin was practically constant in all analyses in comparison with xanthyletin, which showed a significant increase in its amount in symptomatic plants. These data suggest that xanthyletin plays a role in the plant-pathogen interaction, probably as a phytoanticipin in roots. The HPLC-UV method developed here and applied to citrus plants showed an increase in hesperidin and xanthyletin contents in asymptomatic plants. Between the samples analyzed the plants without CVC symptoms are the plants with a positive PCR test for X. fastidiosa, whereas the negative control were the plants that were not inoculated with bacteria. Thus these increases may indicate the presence of the bacteria. Hence the HPLC-UV methods have become a powerful tool for detecting CVC in citrus before the symptoms appear. Thereby, informing the citrus producers in advance when the plant should be removed from the orchard. This could prevent the disease from being transmitted to other plants by insects and also represent significant savings in pesticide application costs (See doi:10.1016/j.phytochem.2015.02.011).

Speaker
Biography:

Dr. Ahmad earned his PhD degree in Botany (Plant Biotechnology) in 2008 from Aligarh Muslim University, Aligarh, India. Subsequently he joined the Plant Biotechnology Laboratory, Botany Department, AMU, Aligarh as Postdoc Fellow and is since been carrying out his research work there. He has published more than 30 research papers in various National and International journals. He has also been conferred with two prestigious awards Viz. Young Scientist of the Year 2010 by Council of Science Technology, Lucknow, UP and Jr. Scientist of The Year 2010 National Environmental Science Academy, New Delhi. He is also a member of several scientific societies and editorial board in various reputed journals.

Abstract:

An unprecedented growth in the plant based pharmaceutical and cosmetic industry has been witnessed during the last decade. The sudden increase in the demand of the medicinal plants has caused a stark increase in the prices of such species. Most of these species are being harvested from the wild, creating ecological imbalances, threatening extinction of many species and depletion of genetic resources. Some of these species are endemic and great disparities in the prices are observed in different parts of the world owing to their poor transportation abilities. European Union and US are among the top trading entities of the world, while, some of the most species rich places in the world such as India contribute very little (0.5%), to the global market. Exploration, propagation and commercialization of the delitescent natural wealth in such phyto-diversity rich areas, holds great potential both in commercial and scientific fields. We have identified some of the important medicinal plant species in India viz. Rauvolfia serpentina, Rauvolfia tetraphylla, Ruta graveolens, Salix tetrasperma, Vitex negundo, Vitex trifolia and Withania somnifera, containing alkaloids with medicinal properties Different strategies were orchestrated using biotechnological applications such as micropropagation, syn-seed production and hairy root culture for enhancing their potential for commercial use. These protocols can be used for propagation, transportation and developing biofactories. Easy availability of these species will benefit the pharmaceutical companies on one hand while also desist destruction of the natural population maintain ecological balance

Speaker
Biography:

Abstract:

Wild fruits are known to play significant role in preventing free radicals mediated diseases. This property is largely due to the phenolic and other metabolites present in the fruits, which are reported to have strong antioxidant activity. Considering to this study was designed to optimize the extraction of phenolic and antioxidants in Berberis asiatica fruits using response surface methodology (RSM). Solvent selection was done based on the preliminary experiments and a three-level-five-factor, Central Composite Design (CCD) consisted of 46 experiments was conducted to analyzed the effect of extraction temperature (X1: 30 – 80°C), extraction time (X2: 30 – 90 min), sample to solvent ratio (X3: 1:10 – 1:50), pH of the solvent (X4: 3 – 5) and solvent concentration (X5: 20 – 80 %) for extraction of total phenolic content (TPC), total anthocyanin content (TAC), total tannins content (TTC), and antioxidant activity [2,2-azinobis-3-ethylbenzthiazoline-6-sul- phonic acid (ABTS)]. Results revealed that extraction temperature (X1), sample to solvent ratio (X3) and solvent concentration (X5) significantly influenced response variables and independent variables. The regression coefficient (R2) was found satisfactory for all the models. The lack of fit was found non-significant (p>0.05) for TPC, TAC, and TTC indicating that the models could adequately fit the experimental data. Response surface analysis showed that under optimal extraction conditions the phenolic antioxidant extraction maximized. These values are in accordance with the predicted values, indicating the success of RSM in optimizing the extraction conditions. This method can be used further for scaling up nutraceutical and pharmaceutical applications and also can be implemented in other fruits of the region for harnessing their potential in commercial sector.

Speaker
Biography:

Abstract:

Common pokeweed plant (Phytolacca Americana) produces pokeweed antiviral protein (PAP) as a defense mechanism against foreign pathogenic invaders. PAP is a ribosome inactivating protein (RIP) and an RNA N-glycosidase that removes specific purine residues from the sarcin/ricin (S/R) loop of large rRNA, arresting protein synthesis at the translocation step. PAP is also a cap-binding protein, and is a potent antiviral agent against many plant, animal, and human viruses. Our research aims to elucidate the antiviral mechanism of RNA depurination and to understand how PAP recognizes and targets various RNA substrates. We have investigated interactions between PAP and Turnip mosaic virus genome linked protein (VPg). VPg functions as a cap analog in cap-independent translation, and potentially target PAP to uncapped IRES-containing RNA. Fluorescence spectroscopy and HPLC techniques were used to quantitatively describe PAP depurination activity and PAP-VPg interactions. PAP binds to VPg with high affinity (29.5 nM); the reaction is enthalpically driven and entropically favored. Further, VPg is a potent inhibitor of PAP depurination of RNA in wheat germ lysate, and competes with structured RNA derived from tobacco etch virus (TEV) for PAP binding. VPg may confer an evolutionary advantage by suppressing one of the plant defense mechanisms, and also suggests the possible use of this protein against the cytotoxic activity of RIPs.

Speaker
Biography:

Dr Ambrose Okem has completed his PhD from University of KwaZulu-Natal and currently doing postdoctoral fellowship at Cape peninsula University of Technology in medicinal plant research. He has published more than 10 papers in reputed journals and has been serving as reviewer of reputed journals.

Abstract:

Hypoxis hemerocallidea is one of the most highly utilized medicinal plants in South Africa and has received considerable attention with regards to its cultivation in order to meet the high demand. To date there is no information about the physiological responses of H. hemerocallidea exposed to heavy metal stress. Our study used an invitro propagation model to study the effect of cadmium (Cd) and aluminium (Al) on H. hemerocallidea plant growth and biochemical composition. Overall, growth of plantlets exposed to Cd and high concentrations of Al was significantly reduced. Furthermore, Cd, Al and Cd: Al combinations significantly reduced the level of photosynthetic pigments. Hypoxis hemerocallidea exhibited some tolerance mechanisms to Cd and Al stress by accumulating high concentrations of free-proline and malondialdehyde after 6 weeks of in vitro culture. Analysis of cell wall and cytoplasmic fractions showed that H. hemerocallidea significantly accumulated higher amounts of Cd and Al in the cytoplasmic fractions from the roots and corms, respectively. These results explain some of the underlining mechanisms involved in the uptake and translocation of heavy metals in H. hemerocallidea. Cd and Al interfered with the uptake and accumulation of essential mineral elements in micropropagted H. hemerocallidea. Thus there is an urgent need to monitor the accumulation of heavy metals in this highly valued medicinal plant to ensure safety and quality of medicinal products.

Speaker
Biography:

Mohamed Lazali has completed his Ph.D at the age of 28 years from National Higher School of Agronomy of Algiers and postdoctoral studies from SupAgro-INRA of Montpellier, France. He has published more than 10 papers in reputed journals and serving as an editorial board member of repute.

Abstract:

Low availability of phosphorus (P) is a major constraint to crop production, and efforts are being made to identify crop genotypes with tolerance to low P and greater P use efficiency (PUE). Cowpea (Vigna unguiculata L. Walp) varieties vary in their adaptation to low-P soils. In order to investigate to what extent this variation may be related to PUE for symbiotic nitrogen fixation (SNF), five genotypes, Adrar, El Kala, Djenet, Tizi Ouzou and Bejaia, were grown in semi-hydroponic culture in a greenhouse at two levels of phosphorus supply corresponding to P sufficiency or P deficiency. At the flowering stage, the biomass of plants and nodules and their P contents was determined after measuring the quantity of N2 fixed. The results showed that nodule and shoot biomass were less when P was deficient. The genotypes which presented the maximum growth during the experiment presented a high efficiency in use of the rhizobial symbiosis calculated as the slope of plant biomass regression as a function of nodulation. Under P deficiency, efficiency in use of P was significantly increased in the tested genotypes and accompanied with an increase of quantity of N2 fixed, especially in the genotypes El Kala, Djenet and Adrar. The genotypes with high PUE for SNF have better growth under P deficiency than the genotypes with low PUE for SNF, confirming that this functional trait may contribute to improve the cowpea-rhizobia symbiosis. Hence the large differences show that traits for more P uptake-efficient plants exist in the tested cowpea genotypes. This opens the possibility to breed for more P uptake-efficient varieties as a way to bring more sparingly soluble soil P into cycling in crop production and obtain capitalization of soil Preserves.

Speaker
Biography:

Fanyana Mtunzi has completed his PhD at the age of 36 years from North-West University (South Africa). He is the Senior Lecturer at Vaal University of South Africa. He has published more than 20 papers in reputed journals and has been serving as an editorial board member of repute.

Abstract:

Rhus leptodictya commonly known as a mountain karee belongs to the family Anacadeceae and has been used since antiquity in tradition medicine. In the present study antimicrobial and antioxidant potentials of the leaves of Rhus leptodictya were studied, followed by isolation of at least one active compound which showed antibacterial and antioxidant potentials. Extractions were performed based on the polarity of the solvent used. The solvents used were hexane, dichloromethane, ethyl acetate, acetone and methanol. Dichloromethane was found to be extracting more compounds than the other used solvents. Thin layer chromatography (TLC) was used to determine the chemical composition of the extracts by employing different solvent systems. The results showed that, of the solvent systems used, namely ethyl acetate: methanol: water (EMW) 40: 5: 1; chloroform: ethyl acetate: formic acid (CEF) 5: 4: 1 and benzene: ethanol: ammonium hydroxide (BEA) 90:10:1, BEA produced better separations. To determine the antioxidant potential of the leaves, 2.2-diphenyl picrylhydrazyl (DPPH) was used. Different spot with different Rf values were found to be active by show of yellow colour on the TLC plate. The yellow colour is due to the proton gained by DPPH when it reacts with active compound. Bioutography results showed that different leaves were active against selected bacterium. Minimum inhibitory concentration studies showed that the methanol extract was more active against B.subtilis and S.pnuemonia at concentration less than 0.1 mg/ml respectively. Dichloromethane extract was found to be the least effective on S.pneumonia, as compared to the methanol, acetone and ethyl acetate extracts. In terms of the total activity, the ethyl acetate concentration showed better total activity than the other extracts studied in this research. A new compound 7,8-trihydroxy-2-(4’hydroxy phenyl)-3-5-[5’’,6’’-dihydroxy-2’’-O-(4’’’hydroxyphenyl)-4-1t-chromen-4’’-one]-41t-chromen-4-one was isolated and characterized by H1-NMR,C13-NMR, MS and IR. According to the literature search, this compound has never been isolated from any plant and it has showed both antioxidant and antibacterial activity.

Speaker
Biography:

Abstract:

The aim of this investigation was to evaluate pest management potential of some medicinal plants, against different strains of Tribolium castaneum, Trogoderma granarium and Cryptolestes ferrugineus, the most common and major insect pests of stored grain. Essential oils extracted from Datura stramonium, Eucalyptus camaldulensis, Moringa oleifera and Nigella sativa with concentrations of 5, 10, 15 and 20% were applied on filter papers to make physical contact or to repel the insects under a constant temperature of 30 ± 2 °C and 65 ± 5% relative humidity. All essential oils exhibited considerable insecticidal and repellent activities against test insects. Among the essential oils, D. stramonium showed the highest toxicity, i.e. 32.26, 23.83 and 56.41% mortality and repellency 74.1, 73.9 and 80.2% against T. castaneum, T. granarium and C. ferrugineus, respectively. Concentration and exposure time significantly affected the mortality and repellency. Overall repellency in all treatments was found higher after 48hr as compared to 24 and 72hr. Bioactivities were observed in the order of D. stramonium > E. camaldulensis > N. sativa > M. oleifera. The results clearly advocate the use of essential oils as integrated pest management technique to protect grain during storage.

Speaker
Biography:

Abstract:

The investigations reported in this manuscript were carried on the screening of One hundred and seventy eight chickpea germplasm lines/cultivars against wilt disease, caused by Fusarium oxysporum f. sp. ciceris. The screening was conducted in vivo (field) conditions. The field screening was accompanied with the study of some epidemiological factors affecting the occurrence and severity of the disease. Among the epidemiological factors maximum temperature range (28-40°C), minimum temperature range (12-24°C), relative humidity (19-44%), soil temperature (26-41°C) and soil moisture range (19-34°C) was studied for affecting the disease incidence/severity. The results revealed that air temperature were positively correlated with diseases. Soil temperature data revealed that in all cultivars disease incidence were maximum as 39°C. Most of plants show 40-50% disease incidence. Disease incidence decreased at 33.5°C. The result of correlation of relative humidity of air and wilt incidence revealed that all cultivars/lines were negatively correlated with relative humidity. With increasing relative humidity wilt incidence decreased and vice versa.