Silver Nanoparticle Regulates Salt Tolerance in Wheat Through Changes in ABA Concentration, Ion Homeostasis, and Defense Systems

Salinity is major abiotic stress affecting crop yield, productivity and reduces the land-usage area for agricultural practices. The purpose of this study is to analyze the effect of green-synthesized silver nanoparticle (AgNP) on physiological traits of wheat (Triticum aestivum) under salinity stress. Using augmented and high-throughput characterization of synthesized AgNPs, this study investigated the proximity of AgNPs-induced coping effects under stressful cues by measuring the germination efficiency, oxidative-biomarkers, enzymatic and non-enzymatic antioxidants, proline and nitrogen metabolism, stomatal dynamics, and ABA content. Taken together, the study shows a promising approach in salt tolerance and suggests that mechanisms of inducing the salt tolerance depend on proline metabolism, ions accumulation, and defense mechanisms. This study ascertains the queries regarding the correlation between nanoparticles use and traditional agriculture methodology; also significantly facilitates to reach the goal of sustainable developments for increasing crop productivity via much safer and greener approachability.

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Agronomical, physiological and molecular evaluation reveals superior salt-tolerance in bread wheat through salt-induced priming approach

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha49212310 ◽

2021 ◽

Vol 49 (2) ◽

pp. 12310

Author(s):

Othman ALZAHRANI ◽

Heba ABOUSEADAA ◽

Taghreed K. ABDELMONEIM ◽

Mohammed A. ALSHEHRI ◽

Mohamed EL-MOGY ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Agronomic Traits ◽

Ion Homeostasis ◽

Crop Productivity ◽

Vital Role ◽

Wheat Crop ◽

Pretreated Group ◽

Mda Content ◽

Agronomical Traits

Salt stress significantly limit wheat crop productivity worldwide. Exposure to non-lethal levels of salt stress, referred to as "salt-priming", allows plants to persist subsequent lethal conditions; the priming effect continues even after an extended salt stress-free period. This study attempted to evaluate the effectiveness of the salt-induced priming approach to cope with the toxic effects of long-term salinity stress in wheat. After 22 days of gradual salt acclamation to reach 250 mM NaCl, plants were recovered for eight days and finally shocked with 250 mM NaCl (priming+shock) for 7 days. After that, physiological parameters and gene expression of six salt-responsive genes were assessed. Additionally, 120 days after germination (at the end of the season), agronomic traits were recorded. Analysis of the agronomical traits revealed higher productivity in the salt-pretreated group (priming+shock) plants than the non-pretreated (shock only). Consistently, salt-pretreated plants maintained higher photosynthetic pigments level and decreased proline and MDA content than non-pretreated, suggesting enhanced salt tolerance. Moreover, salt-pretreated plants sustained high expressional levels of salt-responsive genes (TaNHX1, TaSOS1, TaSOS4, TaHKT1, TaHKT2, and TaAKT1) comparing with non-pretreated, indicating a vital role in ion homeostasis and conferring salt tolerance. Ultimately, this finding could facilitate novel smart approaches to improve wheat productivity under salt stress.

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Salinity Stress: Toward Sustainable Plant Strategies and Using Plant Growth-Promoting Rhizobacteria Encapsulation for Reducing It

Sustainability ◽

10.3390/su132212758 ◽

2021 ◽

Vol 13 (22) ◽

pp. 12758

Author(s):

Roohallah Saberi Riseh ◽

Marzieh Ebrahimi-Zarandi ◽

Elahe Tamanadar ◽

Mojde Moradi Pour ◽

Vijay Kumar Thakur

Keyword(s):

Salt Tolerance ◽

Plant Growth ◽

Ion Homeostasis ◽

Acc Deaminase ◽

Plant Growth Promoting Rhizobacteria ◽

Crop Productivity ◽

Nutrient Mobilization ◽

Hormonal Stimulation ◽

Plant Growth Promoting ◽

Growth Promoting

Salinity is one of the most important abiotic stresses that influences plant growth and productivity worldwide. Salinity affects plant growth by ionic toxicity, osmotic stress, hormonal imbalance, nutrient mobilization reduction, and reactive oxygen species (ROS). To survive in saline soils, plants have developed various physiological and biochemical strategies such as ion exchange, activation of antioxidant enzymes, and hormonal stimulation. In addition to plant adaption mechanisms, plant growth-promoting rhizobacteria (PGPR) can enhance salt tolerance in plants via ion homeostasis, production of antioxidants, ACC deaminase, phytohormones, extracellular polymeric substance (EPS), volatile organic compounds, accumulation of osmolytes, activation of plant antioxidative enzymes, and improvement of nutrients uptake. One of the important issues in microbial biotechnology is establishing a link between the beneficial strains screened in the laboratory with industry and the consumer. Therefore, in the development of biocontrol agents, it is necessary to study the optimization of conditions for mass reproduction and the selection of a suitable carrier for their final formulation. Toward sustainable agriculture, the use of appropriate formulations of bacterial agents as high-performance biofertilizers, including microbial biocapsules, is necessary to improve salt tolerance and crop productivity.

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Parasite defense mechanisms in bees: behavior, immunity, antimicrobials, and symbionts

Emerging Topics in Life Sciences ◽

10.1042/etls20190069 ◽

2019 ◽

Vol 4 (1) ◽

pp. 59-76 ◽

Cited By ~ 2

Author(s):

Alison E. Fowler ◽

Rebecca E. Irwin ◽

Lynn S. Adler

Keyword(s):

Defense Mechanisms ◽

Poor Quality ◽

Future Research ◽

Immune Priming ◽

Social Bees ◽

Bee Health ◽

Landscape Scales ◽

And Function ◽

Solitary Species

Parasites are linked to the decline of some bee populations; thus, understanding defense mechanisms has important implications for bee health. Recent advances have improved our understanding of factors mediating bee health ranging from molecular to landscape scales, but often as disparate literatures. Here, we bring together these fields and summarize our current understanding of bee defense mechanisms including immunity, immunization, and transgenerational immune priming in social and solitary species. Additionally, the characterization of microbial diversity and function in some bee taxa has shed light on the importance of microbes for bee health, but we lack information that links microbial communities to parasite infection in most bee species. Studies are beginning to identify how bee defense mechanisms are affected by stressors such as poor-quality diets and pesticides, but further research on this topic is needed. We discuss how integrating research on host traits, microbial partners, and nutrition, as well as improving our knowledge base on wild and semi-social bees, will help inform future research, conservation efforts, and management.

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Comparative Advantage of Using Biopesticides in Ukrainian Agroecosystems

European Journal of Agriculture and Food Sciences ◽

10.24018/ejfood.2020.2.6.183 ◽

2020 ◽

Vol 2 (6) ◽

Author(s):

Hasrat Arjjumend ◽

Konstantia Koutouki ◽

Olga Donets

Keyword(s):

Shelf Life ◽

Crop Production ◽

Plant Protection ◽

Agricultural Practices ◽

Crop Productivity ◽

Poor Quality ◽

Soil Biology ◽

Chemical Contamination ◽

High Concentration ◽

Irreversible Damage

The use of unsustainable levels of chemical fertilizers and plant protection chemicals has resulted in a steady decline in soil and crop productivity the world over. Soil biology has undergone irreversible damage, coupled with a high concentration of toxic chemical residues in plant tissues and human bodies. Agricultural practices must evolve to sustainably meet the growing global demand for food without irreversibly damaging soil. Microbial biocontrol agents have tremendous potential to bring sustainability to agriculture in a way that is safe for the environment. Biopesticides do not kill non-target insects, and biosafety is ensured because biopesticides act as antidotes and do not lead to chemical contamination in the soil. This article is part of a larger study conducted in Ukraine by researchers at the Université de Montréal with the support of Mitacs and Earth Alive Clean Technologies. The responses of farmers who use biofertilizers (“user farmers”) and those who do not (“non-user farmers”), along with the responses of manufacturers or suppliers of biofertilizers, and research and development (R&D) scientists are captured to demonstrate the advantages of applying microbial biopesticides to field crops. Participants reported a 15-30% increase in yields and crop production after the application of biopesticides. With the use of biopesticides, farmers cultivated better quality fruits, grains, and tubers with a longer shelf life. Moreover, while the risk of crop loss remains high (60-70%) with chemically grown crops, this risk is reduced to 33% on average if crops are grown using biopesticides. The findings indicate that a large proportion of farmers would prefer to use biopesticides if they are effective and high quality products. In this context, the quality and effectiveness of products is therefore very important. Despite their benefits to soil, human health, and ecosystems, biopesticides face significant challenges and competition vis-à-vis synthetic pesticides for a variety of reasons. Therefore, the development of biopesticides must overcome the problems of poor quality products, short shelf life, delayed action, high market costs, and legal/registration issues.

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Arabidopsis heat shock transcription factor HSFA7b positively mediates salt stress tolerance by binding to an E-box-like motif to regulate gene expression

Journal of Experimental Botany ◽

10.1093/jxb/erz261 ◽

2019 ◽

Vol 70 (19) ◽

pp. 5355-5374 ◽

Cited By ~ 11

Author(s):

Dandan Zang ◽

Jingxin Wang ◽

Xin Zhang ◽

Zhujun Liu ◽

Yucheng Wang

Keyword(s):

Gene Expression ◽

Transcription Factors ◽

Heat Shock ◽

Salt Tolerance ◽

Stress Responses ◽

Ion Homeostasis ◽

Cellulose Synthase ◽

Regulate Gene Expression ◽

E Box ◽

Regulate Gene

Abstract Plant heat shock transcription factors (HSFs) are involved in heat and other abiotic stress responses. However, their functions in salt tolerance are little known. In this study, we characterized the function of a HSF from Arabidopsis, AtHSFA7b, in salt tolerance. AtHSFA7b is a nuclear protein with transactivation activity. ChIP-seq combined with an RNA-seq assay indicated that AtHSFA7b preferentially binds to a novel cis-acting element, termed the E-box-like motif, to regulate gene expression; it also binds to the heat shock element motif. Under salt conditions, AtHSFA7b regulates its target genes to mediate serial physiological changes, including maintaining cellular ion homeostasis, reducing water loss rate, decreasing reactive oxygen species accumulation, and adjusting osmotic potential, which ultimately leads to improved salt tolerance. Additionally, most cellulose synthase-like (CSL) and cellulose synthase (CESA) family genes were inhibited by AtHSFA7b; some of them were randomly selected for salt tolerance characterization, and they were mainly found to negatively modulate salt tolerance. By contrast, some transcription factors (TFs) were induced by AtHSFA7b; among them, we randomly identified six TFs that positively regulate salt tolerance. Thus, AtHSFA7b serves as a transactivator that positively mediates salinity tolerance mainly through binding to the E-box-like motif to regulate gene expression.

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Microfluidic Tools for Enhanced Characterization of Therapeutic Stem Cells and Prediction of Their Potential Antimicrobial Secretome

Antibiotics ◽

10.3390/antibiotics10070750 ◽

2021 ◽

Vol 10 (7) ◽

pp. 750

Author(s):

Pasquale Marrazzo ◽

Valeria Pizzuti ◽

Silvia Zia ◽

Azzurra Sargenti ◽

Daniele Gazzola ◽

...

Keyword(s):

Stem Cells ◽

Defense Mechanisms ◽

Live Cells ◽

Label Free ◽

Bacterial Diseases ◽

Prospective Application ◽

Therapy Strategies ◽

Stromal Stem Cells ◽

Different Sources

Antibiotic resistance is creating enormous attention on the development of new antibiotic-free therapy strategies for bacterial diseases. Mesenchymal stromal stem cells (MSCs) are the most promising candidates in current clinical trials and included in several cell-therapy protocols. Together with the well-known immunomodulatory and regenerative potential of the MSC secretome, these cells have shown direct and indirect anti-bacterial effects. However, the low reproducibility and standardization of MSCs from different sources are the current limitations prior to the purification of cell-free secreted antimicrobial peptides and exosomes. In order to improve MSC characterization, novel label-free functional tests, evaluating the biophysical properties of the cells, will be advantageous for their cell profiling, population sorting, and quality control. We discuss the potential of emerging microfluidic technologies providing new insights into density, shape, and size of live cells, starting from heterogeneous or 3D cultured samples. The prospective application of these technologies to studying MSC populations may contribute to developing new biopharmaceutical strategies with a view to naturally overcoming bacterial defense mechanisms.

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Metallothionein: A Multifunctional Protein from Toxicity to Cancer

The International Journal of Biological Markers ◽

10.1177/172460080301800302 ◽

2003 ◽

Vol 18 (3) ◽

pp. 162-169 ◽

Cited By ~ 46

Author(s):

S.E. Theocharis ◽

A.P. Margeli ◽

A. Koutselinis

Keyword(s):

Cell Proliferation ◽

Metal Ion ◽

Defense Mechanisms ◽

Ion Homeostasis ◽

Low Molecular Weight ◽

Multifunctional Protein ◽

Metal Ion Homeostasis ◽

Potential Marker ◽

Proliferation And Apoptosis ◽

Carcinogenic Process

The metallothionein (MT) family is a class of low molecular weight, intracellular and cysteine-rich proteins presenting high affinity for metal ions. Although the members of this family were discovered nearly 40 years ago, their functional significance remains obscure. Four major MT isoforms, MT-1, MT-2, MT-3 and MT-4, have been identified in mammals. MTs are involved in many pathophysiological processes such as metal ion homeostasis and detoxification, protection against oxidative damage, cell proliferation and apoptosis, chemoresistance and radiotherapy resistance. MT isoforms have been shown to be involved in several aspects of the carcinogenic process, cancer development and progression. MT expression has been implicated as a transient response to any form of stress or injury providing cytoprotective action. Although MT participates in the carcinogenic process, its use as a potential marker of tumor differentiation or cell proliferation, or as a predictor of poor prognosis remains unclear. In the present review the involvement of MT in defense mechanisms to toxicity and in carcinogenicity is discussed.

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