Query: Salt stress of plants

title: Salt stress and phyto biochemical responses of plants a review
abstract: The ability of plants to tolerate salts is determined by multiple biochemical pathways that facilitate retention and/or acquisition of water, protect chloroplast functions and maintain ion homeostasis. Essential pathways include those that lead to synthesis of osmotically active metabolites, specific proteins and certain free radical enzymes to control ion and water flux and support scavenging of oxygen radicals. No well defined indicators are available to facilitate the improvement in salinity tolerance of agricultural crops through breeding. If the crop shows distinctive indicators of salt tolerance at the whole plant, tissue or cellular level, selection is the most convenient and practical method. There is therefore a need to determine the underlying biochemical mechanisms of salinity tolerance so as to provide plant breeders with appropriate indicators. In this review, the possibility of using these biochemical characteristics as selection criteria for salt tolerance is discussed.

title: Melatonin: A Small Molecule but Important for Salt Stress Tolerance in Plants
abstract: Salt stress is one of the most serious limiting factors in worldwide agricultural production, resulting in huge annual yield loss. Since 1995, melatonin (N acetyl 5 methoxytryptamine) an ancient multi functional molecule in eukaryotes and prokaryotes has been extensively validated as a regulator of plant growth and development, as well as various stress responses, especially its crucial role in plant salt tolerance. Salt stress and exogenous melatonin lead to an increase in endogenous melatonin levels, partly via the phyto melatonin receptor CAND2/PMTR1. Melatonin plays important roles, as a free radical scavenger and antioxidant, in the improvement of antioxidant systems under salt stress. These functions improve photosynthesis, ion homeostasis, and activate a series of downstream signals, such as hormones, nitric oxide (NO) and polyamine metabolism. Melatonin also regulates gene expression responses to salt stress. In this study, we review recent literature and summarize the regulatory roles and signaling networks involving melatonin in response to salt stress in plants. We also discuss genes and gene families involved in the melatonin mediated salt stress tolerance.

title: Unraveling salt stress signaling in plants.
abstract: Salt stress is a major environmental factor limiting plant growth and productivity. A better understanding of the mechanisms mediating salt resistance will help researchers design ways to improve crop performance under adverse environmental conditions. Salt stress can lead to ionic stress, osmotic stress and secondary stresses, particularly oxidative stress, in plants. Therefore, to adapt to salt stress, plants rely on signals and pathways that re establish cellular ionic, osmotic, and reactive oxygen species (ROS) homeostasis. Over the past two decades, genetic and biochemical analyses have revealed several core stress signaling pathways that participate in salt resistance. The Salt Overly Sensitive signaling pathway plays a key role in maintaining ionic homeostasis, via extruding sodium ions into the apoplast. Mitogen activated protein kinase cascades mediate ionic, osmotic, and ROS homeostasis. SnRK2 (sucrose nonfermenting 1 related protein kinase 2) proteins are involved in maintaining osmotic homeostasis. In this review, we discuss recent progress in identifying the components and pathways involved in the plant's response to salt stress and their regulatory mechanisms. We also review progress in identifying sensors involved in salt induced stress signaling in plants.

title: Ecophysiology and Responses of Plants under Salt Stress
abstract: Role of Ca2+ in alleviating salt stress. An overview on the role of plant volatile organic compounds (VOCs) in salt stress. Adaptive Plasticity of salt stressed root systems. Salt stressed plants and their responses to cadmium. Soil and water management for sustained agriculture in alluvial plains and floodplains exposed to salinity: A case study of Neretva river estuary. In vitro culture and salt stress in plants. Role of Arbuscular mycorrhiza in inducing resistance to salinity. The role of NO in alleviating salt stress in plants. Plant growth regulators and biomass partitioning in crops under salinity. Salt stress and Photosynthesis. Role of Jasmonates in Plant Adaptation to Stress. Salt stress and nitrogen and phosphorus metabolism in plants. Proline and glycinebetaine: chemistry, synthesis and role in plants. Non enzymatic antioxidants and ROS as signaling molecules in plants under salt stress. Role of polyamines in alleviating salt stress. Salt stress: Causes, Types and Physiological Responses of Plants. Role of Phytochrome in Stress Tolerance.  Metabolism and role in plants under salt stress. Breeding citrus. Index.

title: Salt Stress: Causes, Types and Responses of Plants
abstract: Salt stress is one of the major abiotic stresses limiting crop production especially in arid and semi arid regions. It is reported that about 7 of the total earths land and 20 of the total arable area are affected by high salt contents. Reclamation of salt affected soils is necessary as the salt is engulfing the cultivable land day by day. The earliest response of plants to salt stress is reduction in the rate of leaf surface expansion followed by cessation of expansion as the stress intensifies but growth resumes when the stress is relieved. Metabolic processes like photosynthesis, protein synthesis and lipid metabolisms are affected due to salt stress. Salinity is responsible for different types of stresses like, osmotic stress, ionic stress, oxidative stress and hormonal imbalances. The osmotic stress is caused by the excess of Na+ and Cl ions in the soil that decrease the osmotic potential and hampers the water uptake and nutrients. Low molecular mass compounds known as compatible solutes is accumulated under salt stress. These compatible solutes include proline, glycinebetaine, sugars, proteins, polyols, etc. They do not interfere with the normal biochemical reactions and helps the plants in building the resistance against the stress.

title: Effect of Salt Stress on Plants: A Review
abstract: Salinity may be a major abiotic stress, limiting growth and productivity of plants in many areas of the world. The ability of plants to tolerate salt is set by multiple biochemical pathways that facilitate retention and/or acquisition of water, defend plastid functions, and maintain ion homeostasis. The ability of plants to detoxify radicals underneath conditions of salt stress is perhaps the foremost essential demand. Several salt tolerant species accumulate methylated metabolites that play crucial twin roles as osmoprotectants and as radical scavengers. Their synthesis is correlated with stress induced enhancement of photorespiration. In this paper, plant responses to salinity stress are reviewed with stress on physiological, biochemical, and molecular mechanisms of salt tolerance.  Salinity, plant growth, metabolites, biochemical, salt tolerant species Cite this Article Meenakshi Tripathi. Effect of salt stress on plants a review.  2015; 4(3) 35 51p.

title: Gene Expression Profiling of Plants under Salt Stress
abstract: Soil salinity is among the leading environmental stresses affecting global agriculture, causing billions of dollars in crop damages every year. Regardless of the cause, ion toxicity, water deficit, or nutritional imbalance, high salinity in the root zone severely impedes normal plant growth and development, resulting in reduced crop productivity or crop failure. Development of salt tolerant cultivars is an attractive and economical approach to solving this problem. Although several salt tolerant plant genotypes have been developed through transgenic approaches, often they have failed or exhibited limited success under field saline conditions. This is due to several reasons, including the fact that plant growth and development under saline conditions in the field is often influenced by cumulative effects of multiple environmental stresses and genetic factors, which may not have been considered during the development of salt tolerant transgenic plants. Adoption of inappropriate screening techniques or selection criteria may also lead to selection of genotypes that may not be stress tolerant in a real sense. In most plant species, salt tolerance is a genetically complex trait, often modulated by multiple biosynthetic and signaling pathways. Cross talks among various stress controlling pathways have been observed under salt stress, many of which are regulated by transcription factors. Thus, a comprehensive knowledge of the up and downregulating genes under salt stress is necessary, which would provide a better understanding of the interactions among pathways in response to salt stress. Attaining such knowledge is a good step toward successful development of salt tolerant crop cultivars. To this end, DNA microarray technology has been employed to study expression profiles in different plant species and at varying developmental stages in response to salt stress. As a result, large scale gene expression profiles under salt stress are now available for many plant species, including Arabidopsis, rice, barley, and ice plant. Examinations of such gene expression profiles will help understand the complex regulatory pathways affecting plant salt tolerance and potentially functional characterization of unknown genes, which may be good candidates for developing plants with field salt tolerance. In this article, we review and discuss the current knowledge of plant salt tolerance and the extent to which expression profiling has helped, or will help, a better understanding of the genetic basis of plant salt tolerance. We also discuss possible approaches to improving plant salt tolerance using various tools of biotechnology.

title: Biochar soil amendment on alleviation of drought and salt stress in plants: a critical review
abstract: Drought and salt stress negatively affect soil fertility and plant growth. Application of biochar, carbon rich material developed from combustion of biomass under no or limited oxygen supply, ameliorates the negative effects of drought and salt stress on plants. The biochar application increased the plant growth, biomass, and yield under either drought and/or salt stress and also increased photosynthesis, nutrient uptake, and modified gas exchange characteristics in drought and salt stressed plants. Under drought stress, biochar increased the water holding capacity of soil and improved the physical and biological properties of soils. Under salt stress, biochar decreased Na+ uptake, while increased K+ uptake by plants. Biochar mediated increase in salt tolerance of plants is primarily associated with improvement in soil properties, thus increasing plant water status, reduction of Na+ uptake, increasing uptake of minerals, and regulation of stomatal conductance and phytohormones. This review highlights both the potential of biochar in alleviating drought and salt stress in plants and future prospect of the role of biochar under drought and salt stress in plants.

title: Regulation of Na+ and K+ homeostasis in plants: towards improved salt stress tolerance in crop plants
abstract: Soil salinity is a major abiotic stress that results in considerable crop yield losses worldwide. However, some plant genotypes show a high tolerance to soil salinity, as they manage to maintain a high K+/Na+ ratio in the cytosol, in contrast to salt stress susceptible genotypes. Although, different plant genotypes show different salt tolerance mechanisms, they all rely on the regulation and function of K+ and Na+ transporters and H+ pumps, which generate the driving force for K+ and Na+ transport. In this review we will introduce salt stress responses in plants and summarize the current knowledge about the most important ion transporters that facilitate intra and intercellular K+ and Na+ homeostasis in these organisms. We will describe and discuss the regulation and function of the H+ ATPases, H+ PPases, SOS1, HKTs, and NHXs, including the specific tissues where they work and their response to salt stress.

title: Alleviation of Salt Stress in Pepper (Capsicum annum L. Plants by Plant Growth Promoting Rhizobacteria.
abstract: In the present study, we demonstrate that the growth of salt stressed pepper plants is improved by inoculation with plant growth promoting rhizobacteria (PGPR) Three PGPR strains (Microbacterium oleivorans KNUC7074, Brevibacterium iodinum KNUC7183, and Rhizobium massiliae KNUC7586) were isolated from the rhizosphere of pepper plants growing in saline soil, and pepper plants inoculated with these PGPR strains exhibited significantly greater plant height, fresh weight, dry weight, and total chlorophyll content than non inoculated plants. In addition, salt stressed pepper plants that were inoculated with B. iodinum KNUC7183 and R. massiliae KNUC7586 possessed significantly different total soluble sugar and proline contents from non inoculated controls, and the activity of several antioxidant enzymes (ascorbate peroxidase, guaiacol peroxidase, and catalase) was also elevated in PGPR treated plants under salt stress. Overall, these results suggest that the inoculation of pepper plants with M. oleivorans KNUC7074, B. iodinum KNUC7183, and R. massiliae KNUC7586 can alleviate the harmful effects of salt stress on plant growth.