Showing papers by "Sarvajeet Singh Gill published in 2013"

Silver nanoparticles in soil–plant systems

Abstract: Silver nanoparticles (AgNPs) have broad spectrum antimicrobial/biocidal properties against all classes of microorganisms and possess numerous distinctive physico-chemical properties compared to bulk Ag. Hence, AgNPs are among the most widely used engineered NPs in a wide range of consumer products and are expected to enter natural ecosystems including soil via diverse pathways. However, despite: (i) soil has been considered as a critical pathway for NPs environmental fate, (ii) plants (essential base component of all ecosystems) have been strongly recommended to be included for the development of a comprehensive toxicity profile for rapidly mounting NPs in varied environmental compartments, and (iii) the occurrence of an intricate relationship between “soil–plant systems” where any change in soil chemical/biological properties is bound to have impact on plant system, the knowledge about AgNPs in soils and investigations on AgNPs–plants interaction is still rare and in its rudimentary stage. To this end, the current paper: (a) overviews sources, status, fate, and chemistry of AgNPs in soils, AgNPs-impact on soil biota, (b) critically discusses terrestrial plant responses to AgNPs exposure, and (c) illustrates the knowledge-gaps in the current perspective. Based on the available literature critically appraised herein, a multidisciplinary integrated approach is strongly recommended for future research in the current direction aimed at unveiling the rapidly mounting AgNPs-fate, transformation, accumulation, and toxicity potential in “soil–plant systems,” and their cumulative impact on environmental and human health.

A DESD-box helicase functions in salinity stress tolerance by improving photosynthesis and antioxidant machinery in rice (Oryza sativa L. cv. PB1)

Abstract: The exact mechanism of helicase-mediated salinity tolerance is not yet understood. We have isolated a DESD-box containing cDNA from Pisum sativum (Pea) and named it as PDH45. It is a unique member of DEAD-box helicase family; containing DESD instead of DEAD/H. PDH45 overexpression driven by constitutive cauliflower mosaic virus-35S promoter in rice transgenic [Oryza sativa L. cv. Pusa Basmati 1 (PB1)] plants confers salinity tolerance by improving the photosynthesis and antioxidant machinery. The Na+ ion concentration and oxidative stress parameters in leaves of the NaCl (0, 100 or 200 mM) treated PDH45 overexpressing T1 transgenic lines were lower as compared to wild type (WT) rice plants under similar conditions. The 200 mM NaCl significantly reduced the leaf area, plant dry mass, net photosynthetic rate (PN), stomatal conductance (gs), intercellular CO2 (Ci), chlorophyll (Chl) content in WT plants as compared to the transgenics. The T1 transgenics exhibited higher glutathione (GSH) and ascorbate (AsA) contents under salinity stress. The activities of antioxidant enzymes viz. superoxide dismutase (SOD), ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and glutathione reductase (GR) were significantly higher in transgenics; suggesting the existence of an efficient antioxidant defence system to cope with salinity induced-oxidative damage. Yeast two-hybrid assay indicated that the PDH45 protein interacts with Cu/Zn SOD, adenosine-5′-phosphosulfate-kinase, cysteine proteinase and eIF(4G), thus confirming the involvement of ROS scavenging machinery in the transgenic plants to provide salt tolerance. Furthermore, the T2 transgenics were also able to grow, flower, and set viable seeds under continuous salinity stress of 200 mM NaCl. This study provides insights into the mechanism of PDH45 mediated salinity stress tolerance by controlling the generation of stress induced reactive oxygen species (ROS) and also by protecting the photosynthetic machinery through a strengthened antioxidant system.

Physiological Role of Nitric Oxide in Plants Grown Under Adverse Environmental Conditions

Abstract: Plant production in the recent times is facing various kinds of abiotic stress which are considered as major factors limiting crop productivity worldwide. Radical global climatic and other environmental changes have forced the need for a better understanding of plant stress responses and tolerance, particularly in the light of increasing intense stressors like salinity, drought, flooding, toxic metals, temperature extremes, high-light intensity, UV-radiation, herbicides, ozone, among others. Over the past decade, the understanding of plant adaptation to environmental stress, including both constitutive and inducible determinants, has grown considerably. Exploring suitable crop improvements or ways to alleviate stress is one of the tasks of plant biologists. Research on nitric oxide (NO) in plants has gained considerable attention in recent years mainly due to its function in plant growth and development and as a key signaling molecule in different intracellular processes. The role of NO in stress responses in plants has been increasingly focused in plant science over the last decade. NO is an essential signaling molecule with multiple physiological and biochemical functions involving the induction of different intracellular processes, including the expression of defense-related and redox-regulated genes in the detoxification of abiotic and biotic stress-induced reactive oxygen species (ROS). Although significant progress has been made in understanding NO biosynthesis and signaling in plants, several crucial questions remain unanswered. In this chapter, we review recent progress in NO research in a broader context of abiotic stress tolerance and discuss its diverse roles in physiological and biochemical processes in plants and the protective mechanisms it exhibits towards abiotic stress tolerance.

Genome-wide analysis of glutathione reductase (GR) genes from rice and Arabidopsis

Abstract: Plant cells and tissues remain always on risk under abiotic and biotic stresses due to increased production of reactive oxygen species (ROS). Plants protect themselves against ROS induced oxidative damage by the upregulation of antioxidant machinery. Out of many components of antioxidant machinery, glutathione reductase (GR, EC 1.6.4.2) and glutathione (GSH, γ-Glu-Cys-Gly) play important role in the protection of cell against oxidative damage. In stress condition, the GR helps in maintaining the reduced glutathione pool for strengthening the antioxidative processes in plants. Present study investigates genome wide analysis of GR from rice and Arabidopsis. We were able to identify 3 rice GR genes (LOC_Os02 g56850, LOC_Os03 g06740, LOC_Os10 g28000) and 2 Arabidopsis GR genes (AT3G54660, AT3G24170) from their respective genomes on the basis of their annotation as well as the presence of pyridine nucleotide-disulphide oxidoreductases class-I active site. The evolutionary relationship of the GR genes from rice and Arabidopsis genomes was analyzed using the multiple sequence alignment and phylogenetic tree. This revealed evolutionary conserved pyridine nucleotide-disulphide oxidoreductases class-I active site among the GR protein in rice and Arabidopsis. This study should make an important contribution to our better understanding of the GR under normal and stress condition in plants.

Plant acclimation to environmental stress

Abstract: 1 Plant Acclimation to Environmental Stress using Priming Agents Panagiota Filippou, Georgia Tanou, Athanassios Molassiotis, Vasileios Fotopoulos 2 Facing the Cold Stress by Plants in the Changing Environment: Sensing, Signaling and Defending Mechanisms Prince Thakur, Harsh Nayyar 3 Drought and Salinity Tolerant Biofuel Crops for the Thar Desert Karan Malhotra, Gulshan K Chhabra, Rachana Jain, Vinay Sharma, Shashi Kumar 4 Strategies for the salt tolerance in bacteria and archeae and its implications in developing crops for adverse conditions Satya P. Singh, Vikram Raval, Megha K. Purohit 5 Adverse Effects of Abiotic Stresses on Medicinal and Aromatic Plants and their Alleviation by Calcium M. Naeem, M. Nasir Khan, M. Masroor A. Khan, Moinuddin 6 Role of DREB-like Proteins in Improving Stress Tolerance of Transgenic Crops Deepti Jain, Debasis Chattopadhyay 7 Homeobox Genes as Potential Candidates for Crop Improvement under Abiotic Stress Annapurna Bhattacharjee, Mukesh Jain 8 APETALA2 Gene Family: Potential for Crop Improvement under Adverse Conditions Sowmya Krishnaswamy, Shiv Verma, Muhammad H. Rahman, Nat Kav 9 Osmoprotectants: Potential for Crop Improvement under Adverse Conditions Saurabh C. Saxena, Harmeet Kaur, Pooja Verma, Bhanu P. Petla, Venkateswara R. Andugula, Manoj Majee 10 Epigenetic Modifications in Plants under Adverse Conditions - Agricultural Applications Alex Boyko, Igor Kovalchuk 11 Physiological Role of Nitric Oxide in Plants Grown under Adverse Environmental Conditions Mirza Hasanuzzaman, Sarvajeet Singh Gill, Narendra Tuteja, Masayuki Fujita 12 Weeds as a Source of Genetic Material for Crop Improvement under Adverse Conditions Bhumesh Kumar, Meenal Rathore, A. R. G. Ranganatha 13 Sustainable Agriculture Practices for Food and Nutritional Security Vibha Dhawan 14 Arbuscular Mycorrhiza: Approaches for Abiotic Stress Tolerance in Crop Plants for Sustainable Agriculture Rupam Kapoor, Heikham Evelin, Piyush Mathur, Bhoopander Giri 15 Biofertilizers: A Sustainable Eco-friendly Agricultural Approach to Crop Improvement Ranjan Kumar Sahoo, Deepak Bhardwaj, Narendra Tuteja 16 Plant Pathogen Interactions: Crop Improvement under Adverse Conditions Kamal Kumar, Praveen Kumar Verma 17 Can G-proteins be the key proteins for overcoming environmental stresses and increasing crop yield in plants? Deepak Bhardwaj, Suman Lakhanpaul, Narendra Tuteja

Climate change and plant abiotic stress tolerance

Abstract: In this ready reference, a global team of experts comprehensively cover molecular and cell biology-based approaches to the impact of increasing global temperatures on crop productivity.

Crop Improvement Under Adverse Conditions

Abstract: No wonder you activities are, reading will be always needed. It is not only to fulfil the duties that you need to finish in deadline time. Reading will encourage your mind and thoughts. Of course, reading will greatly develop your experiences about everything. Reading crop improvement under adverse conditions is also a way as one of the collective books that gives many advantages. The advantages are not only for you, but for the other peoples with those meaningful benefits.

Nanobiotechnology: Scope and Potential for Crop Improvement

Abstract: The production level of foodgrains has become an issue of concern as it has shown a downward trend during the last decade. Since, there has been a drastic decrease in natural resources; it is through agriculture that we can visualize a self sustainable world. The growth in agriculture can be achieved only by increasing productivity through an effective use of modern technology as the land and water resources are limited. Nanobiotechnology provides the tool and technological platforms to advance agricultural productivity through genetic improvement of plants, delivery of genes and drug molecules, to specific sites at cellular levels. The interest is increasing with suitable techniques and sensors for precision in agriculture, natural resource management, early detection of pathogens and contaminants in food products and smart delivery systems for agrochemicals like fertilizers and pesticides. To achieve the goals of “nano-agriculture”, detailed investigation on the ability of nanoparticles to penetrate plant cell walls and work as smart treatment-delivery systems in plants, is needed. In this chapter, thorough studies and reliable information regarding the effects of nanomaterials on plant physiology and crop improvement at the organism level, are discussed.

Improving Crop Productivity in Sustainable Agriculture

Abstract: PART I CLIMATE CHANGE AND ABIOTIC STRESS FACTORS Climate Change and Food Security (R.B. Singh) Improving Crop Productivity Under Changing Environment (Navjot K. Dhillon, Satbir S. Gosal, and Manjit S. Kang) Genetic Engineering for Acid Soil Tolerance in Plants (Sagarika Mishra, Lingaraj Sahoo and, Sanjib Kumar Panda) Evaluation of Tropospheric O3 Effects on Global Agriculture: A New Insight (Richa Rai, Abhijit Sarkar, S.B. Agrawal, and Madhoolika Agrawal) PART II METHODS TO IMPROVE CROP PRODUCTIVITY Mitogen Activated Protein Kinases in Abiotic Stress Tolerance in Crop Plants: Omics Approaches (Monika Jaggi, Meetu Gupta, Narendra Tuteja, and Alok Krishna Sinha) Plant Growth Promoting Rhizobacteria Mediated Amelioration of Abiotic and Biotic Stresses for Increasing Crop Productivity (Vasvi Chaudhry, Suchi Srivastava, Puneet Singh Chauhan, Poonam C. Singh, Aradhana Mishra, and Chandra Shekhar Nautiyal) Are Viruses Always Villains? The roles Plant Viruses May Play in Improving Plant Responses to Stress (Stephen J. Wylie , and Michael G.K. Jones) Risk Assessment of Abiotic Stress Tolerant GM Crops (Paul Howles, and Joe Smith) Biofertilizers: Potential for Crop Improvement Under Stressed Condition (Alok Adholeya, and Manab Das) PART III SPECIES-SPECIFIC CASE STUDIES SECTION IIIA GRAMINOIDS Rice: Genetic Engineering Approaches for Abiotic Stress Tolerance, Retrospects and Prospects (Salvinder Singh, M.K. Modi, Sarvajeet Singh Gill, and Narendra Tuteja) Rice: Genetic Engineering Approaches to Enhance Grain Iron Content (Salvinder Singh, D. Sudhakar, and M.K. Modi) Pear Millet: Genetic Improvement for Tolerance to Abiotic Stresses (O.P. Yadav, K.N. Rai, and S.K. Gupta) Bamboo: Applications of Plant Tissue Culture Techniques for Genetic Improvement of Dendrocalamus Strictus Nees (C. K. John, and V. A. Parasharami) SECTION IIIB LEGUMINOSAE Groundnut: Genetic Approaches to Enhance Adaptation of Groundnut (Arachis Hypogaea, L.) to Drought (Nageswara Rao R.C., Sheshshayee M.S., Karaba N. Nataraja, Rohini Sreevathsa, Rama N., Kumaraswamy S., Prasad T.G., and Udayakumar M.) Chickpea: Crop Improvement Under Changing Environment Conditions (B. K. Sarmah, S. Acharjee, and H.C. Sharma) Grain Legumes: Biotechnological Interventions in Crop Improvement for Adverse Environments (Pooja Bhatnagar-Mathur, Paramita Palit, Ch Sridhar Kumar, D. Srinivas Reddy, and Kiran K. Sharma) Pulse Crops: Biotechnological Strategies to Enhance Abiotic Stress Tolerance (S. Ganeshan, P.M. Gaur, and R.N. Chibbar) SECTION IIIC ROSACEAE Improving Crop Productivity and Abiotic Stress Tolerance in Cultivated Fragaria Using Omics and Systems Biology Approach (Jens Rohloff, Pankaj Barah, and Atle M. Bones) Rose: Improvement for Crop Productivity (Madhu Sharma, Kiran Kaul, Navtej Kaur, Markandey Singh, D. Dhayani, and Paramvir Singh Ahuja)

Mechanism of Cadmium Toxicity and Tolerance in Crop Plants

Abstract: Heavy metal pollution of arable soils is one of the major limiting factors affecting the plant growth and productivity worldwide. In particular, contamination of agricultural soils with cadmium (Cd) is one of the most serious agricultural problems in the world. Although Cd has no biological function in plants, it becomes easily available to the rooted plants. As soon as Cd enters the roots, it can reach the xylem through an apoplastic and/or symplastic pathway. Plants show a differing metal distribution and accumulation pattern among different plant parts. Once Cd enters the cells, it may disturb many physiological and metabolic processes in plants. Cd is a highly toxic nonessential element to plant growth and development and causes plant death even at low concentrations. It evokes a whole array of toxic effects, due to its long biological half-life and storage in plant vacuoles, interacts with carbon and nitrogen metabolism, interferes with sulphur assimilation and glutathione metabolism and decreases the absorption of nutritional elements, and causes oxidative damage. Plants are very well equipped with a wide array of defense mechanisms to cope with Cd accumulation and toxicity. The present chapter discusses the mechanisms of Cd toxicity and tolerance in crop plants.

Salinity Tolerance of Avicennia officinalis L. (Acanthaceae) from Gujarat Coasts of India

Abstract: Greenhouse experiments were conducted to assess the effects of soil salinity on Avicennia officinalis L. (Acanthaceae) of Gujarat at different salinity levels (0.2, 5.4, 10.3, 15.4, 20, 25.6, 30, and 34ppt). Growth and physiological characteristics were monitored over the subsequent 6 months. Total dry weight of plant tissues increased up to 5.1ppt, but decreased at high salt concentrations. Organic solute concentration, such as soluble sugars, proline, and glycine betaine, decreased with an increase in salinity concentration up to 5.1ppt, but increased with a further increase in salinity (above 5.1ppt). There was an increase in total chlorophyll and decrease in total free amino acids and protein oxidation up to 5.1 ppt, after that it showed the reverse trend with a further increase in salinity. Hydrogen peroxide (H2O2) continuously increased with an increase in salinity stress. Membrane leakage and lipid peroxidation decreased at 5.1 ppt, but increased with a further increase in salinity levels. The activity of antioxidant enzymes, such as superoxide dismutase, catalase, ascorbate peroxidase, and glutathione reductase, decreased at 5.1ppt, but increased with a further increase in salinity levels. The overall result suggests that A. officinalis has a remarkably high degree of salinity tolerance, and shows an optimal growth and high activity of reactive oxygen species-scavenging antioxidant enzymes when soil water salinity was 5.1ppt.

Plant Stress and Biotechnology

Abstract: Nowadays plant biotechnology faces many important challenges, including the development of strategies to secure global food supply, the adequate acquisition and management of plant derived products for human subsistence (woods, pharmaceuticals, biofuels, etc.), as well as the development of plants that can cope with the constant effects of biotic and abiotic stress conditions in the era of changing climatic conditions. Being sessile, plants are able to adapt or acclimate after constant exposition to environmental stress conditions; nevertheless, in most cases growth rate and yield are reduced below optimum levels. Increases in global warming, climatic changes, soil degradation, and pollution, are affecting dramatically the plant kingdom. Advances in plant molecular biology and biotechnology have changed our capabilities for gene discovery, the study of tissue-specific promoters, the functional characterization of genes, gene pyramiding, and the generation of efficient methods for plant genetic transformation and/or plant genome manipulation. All of these beneficial applications offer the possibility to achieve pest resistance, abiotic stress tolerance, crop yield improvement, and excel food nutritional quality. In this regard, the understanding of plant molecular mechanisms underlying biotic and abiotic stress tolerance, the characterization of hormone mediated signaling pathways, and the molecular interaction and crosstalk among pathways will improve our knowledge in plant stress biology. This special issue consists of six papers related to abiotic and biotic plant stress. Papers by M. Perez-Clemente et al., L.-T. Yang et al., and A. S. Dubrovina et al. present interesting reviews of diverse topics such as plant response to stress, aluminium tolerance in higher plants, and pre-mRNA splicing under plant stress conditions, respectively. The following three are research papers focusing on identification of rice genes in response to heat stress (Y. Cao et al.), transcriptional profiling of canker-resistant transgenic sweet orange (X.-Z. Fu and J.–H. Liu), and characterization of the newly developed soybean cultivar (DT2008) under drought tolerance (C. V. Ha et al.). M. Perez-Clemente et al. outline the main biotechnological approaches used to study plant stress responses, such as the “omics” technologies (genomics, proteomics, and metabolomics), and transgenic-based approaches. As well, considerable advances in plant physiology, genetics, and molecular biology are included, which have greatly improved our understanding of plant responses to abiotic stress conditions. A. S. Dubrovina et al. review recent data on alternative splicing in plant genes involved in stress signaling; in particular the authors focus on the occurrence, properties, and functional consequences of unconventional splicing and splicing-like events in plants. Precursor mRNAs with introns can undergo alternative splicing to produce multiple transcripts from the same gene by differential use of splice sites, thereby increasing the transcriptome and proteome complexity. In order to survive the stress conditions, plants actively employ pre-mRNA splicing as a mechanism to regulate expression of stress-responsive genes and reprogram intracellular regulatory networks. This review is attractive since it provides data on transcript diversity generated in response to environmental stresses, an aspect that could be important to plant biotechnology in terms of developing new strategies for crop breeding and protection. L.-T. Yang et al. describe the main mechanisms related to aluminium tolerance in plants facing acidic soils, where aluminium toxicity is an important factor that limits crop productivity. Importance is given to the secretion of organic acid ions from plant roots and the possible mechanisms that regulate this process, including ion channels or transporters, internal concentration of organic acid ions, root plasma membrane H-ATPase, and temperature, among others. As well, transgenic plants attempting to increase the secretion and biosynthesis of organic acid anions as an approach for the acquisition of aluminium tolerance are discussed as potential research area. In the research article presented by Y. Cao et al., the importance of studying heat stress responses in plant crops, such as rice, is emphasized, in particular, because of global warming and its increasing impact on crop production at the present time. In rice, several papers involving heat shock proteins (HSPs) and heat shock transcription factors in the heat stress response have been published; nevertheless, little is known about other genes induced under this condition. Based on cDNA-AFLP analysis, the authors identified 49 differentially expressed genes, including genes related to carbohydrate metabolism, photosynthesis and energy production, and amino acid and polyamine metabolism and transport, among others, as heat stress-responsive genes in rice. The possible implication of these genes in heat stress response is discussed. In the research article presented by X.-Z. Fu and J.-H. Liu, they analyzed the global transcriptional profiling of transgenic sweet orange line (TG9) using the Affymetrix Citrus GeneChip microarray. TG9 line overexpresses Malus domestica spermidine synthase (MdSPDS1); it has increased levels of the polyamines, spermidine and spermine, and confers canker resistance. Nowadays, the gene regulation network in polyamine which involved plant pathogen response is largely unclear, particularly in perennial plants like citrus. A profile of genes up- and downregulated under high polyamine levels in the TG9 line is presented. It is hypothesized that genes implicated in stimulus response and immune system process, cell wall and transcriptional regulation, and cellular and metabolism processes, such as starch and sucrose metabolism, glutathione metabolism, biosynthesis of phenylpropanoids, and plant hormones play major roles in the canker resistance of TG9. In the research article presented by C. V. Ha et al., drought-tolerant phenotypes of DT2008 soybean variety and W82 soybean cultivar were compared by examining the dehydration-induced water loss and membrane stability of the shoot parts of young seedlings. DT2008 is an improved variety of soybean that shows enhanced drought tolerance and stable yield in field conditions. The authors propose that further comparisons between DT2008 and W82 cultivars using molecular approaches will enable the identification of mutations associated with drought tolerance in DT2008, which could be used to improve drought tolerance in soybean cultivars through genetic engineering. In the research article presented by C. V. Ha et al., they compared the drought-tolerant phenotypes of DT2008 soybean variety and W82 soybean cultivar by examining the dehydration-induced water loss and membrane stability of the shoot parts of the young seedlings. DT2008 is an improved variety of soybean that showed enhanced drought tolerance and stable yield in the field conditions. Molecular analysis between these soybean cultivars will enable the identification of mutations, which could be candidates for genetic engineering to improve drought tolerance in soybean cultivars.