The Barley S-Adenosylmethionine Synthetase 3 Gene HvSAMS3 Positively Regulates the Tolerance to Combined Drought and Salinity Stress in Tibetan Wild Barley

Drought and salinity are two of the most frequently co-occurring abiotic stresses. Despite recent advances in the elucidation of the effects of these stresses individually during the vegetative stage of plants, significant gaps exist in our understanding of the combined effects of these two frequently co-occurring stresses. Here, Tibetan wild barley XZ5 (drought tolerant), XZ16 (salt tolerant), and cultivated barley cv. CM72 (salt tolerant) were subjected to drought (D), salinity (S), or a combination of both treatments (D+S). Protein synthesis is one of the primary activities of the green part of the plant. Therefore, leaf tissue is an important parameter to evaluate drought and salinity stress conditions. Sixty differentially expressed proteins were identified by mass spectrometry (MALDI-TOF/TOF) and classified into 9 biological processes based on Gene Ontology annotation. Among them, 21 proteins were found to be expressed under drought or salinity alone; however, under D+S, 7 proteins, including S-adenosylmethionine synthetase 3 (SAMS3), were exclusively upregulated in drought-tolerant XZ5 but not in CM72. HvSAMS3 carries both N-terminal and central domains compared with Arabidopsis and activates the expression of several ethylene (ET)-responsive transcription factors. HvSAMS3 is mainly expressed in the roots and stems, and HvSAMS3 is a secretory protein located in the cell membrane and cytoplasm. Barley stripe mosaic virus-based virus-induced gene silencing (BSMV-VIGS) of HvSAMS3 in XZ5 severely compromised its tolerance to D+S and significantly reduced plant growth and K+ uptake. The reduced tolerance to the combined stress was associated with the inhibition of polyamines such as spermidine and spermine, polyamine oxidase, ethylene, biotin, and antioxidant enzyme activities. Furthermore, the exogenous application of ethylene and biotin improved the tolerance to D+S in BSMV-VIGS:HvSAMS3-inoculated plants. Our findings highlight the significance of HvSAMS3 in the tolerance to D+S in XZ5.

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Tolerance to Drought, Low pH and Al Combined Stress in Tibetan Wild Barley Is Associated with Improvement of ATPase and Modulation of Antioxidant Defense System

International Journal of Molecular Sciences ◽

10.3390/ijms19113553 ◽

2018 ◽

Vol 19 (11) ◽

pp. 3553 ◽

Cited By ~ 3

Author(s):

Imrul Ahmed ◽

Umme Nadira ◽

Cheng-Wei Qiu ◽

Fangbin Cao ◽

Guoping Zhang ◽

...

Keyword(s):

Antioxidant Enzyme ◽

Enzyme Activities ◽

Wild Barley ◽

Low Ph ◽

Antioxidant Enzyme Activities ◽

Genotypic Differences ◽

Combined Stress ◽

Tibetan Wild Barley ◽

Drought Tolerant ◽

Peg Stress

Aluminum (Al) toxicity and drought are two major constraints on plant growth in acidic soils, negatively affecting crop performance and yield. Genotypic differences in the effects of Al/low pH and polyethyleneglycol (PEG) induced drought stress, applied either individually or in combination, were studied in Tibetan wild (XZ5, drought-tolerant; XZ29, Al-tolerant) and cultivated barley (Al-tolerant Dayton; drought-tolerant Tadmor). Tibetan wild barley XZ5 and XZ29 had significantly higher H+-ATPase, Ca2+Mg2+-ATPase, and Na+K+-ATPase activities at pH 4.0+Al+PEG than Dayton and Tadmor. Moreover, XZ5 and XZ29 possessed increased levels in reduced ascorbate and glutathione under these conditions, and antioxidant enzyme activities were largely stimulated by exposure to pH 4.0+PEG, pH 4.0+Al, and pH 4.0+Al+PEG, compared to a control and to Dayton and Tadmor. The activity of methylglyoxal (MG) was negatively correlated with increased levels of glyoxalase (Gly) I and Gly II in wild barley. Microscopic imaging of each genotype revealed DNA damage and obvious ultrastructural alterations in leaf cells treated with drought or Al alone, and combined pH 4.0+Al+PEG stress; however, XZ29 and XZ5 were less affected than Dayton and Tadmor. Collectively, the authors findings indicated that the higher tolerance of the wild barley to combined pH 4.0+Al+PEG stress is associated with improved ATPase activities, increased glyoxalase activities, reduced MG, and lower reactive oxygen species levels (like O2− and H2O2) due to increased antioxidant enzyme activities. These results offer a broad comprehension of the mechanisms implicated in barley’s tolerance to the combined stress of Al/low pH and drought, and may provide novel insights into the potential utilization of genetic resources, thereby facilitating the development of barley varieties tolerant to drought and Al/low pH stress.

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Physiological and antioxidant responses of cultivated and wild barley under salt stress

Plant Soil and Environment ◽

10.17221/169/2020-pse ◽

2020 ◽

Vol 66 (No. 7) ◽

pp. 334-344

Author(s):

Zahra Jabeen ◽

Nazim Hussain ◽

Faiza Irshad ◽

Jianbin Zeng ◽

Ayesha Tahir ◽

...

Keyword(s):

Dna Damage ◽

Salt Stress ◽

Wild Barley ◽

Antioxidant Defense System ◽

Oxidative Capacity ◽

Plant Tissues ◽

Salt Tolerant ◽

Antioxidant Responses ◽

Tibetan Wild Barley ◽

High Degree

Saline soil is a critical environmental problem affecting crop yield worldwide. Tibetan wild barley is distinguished for its vast genetic diversity and high degree of tolerance to abiotic stress, including salinity. The present study compared the response of antioxidant defense system in the XZ16 wild and CM72 cultivated barleys to salt stress. Wild barley was relatively more tolerant than cultivated CM72, salt-tolerant cultivar, with less Na+ uptake and more K+, Ca2+, and Mg2+ retention in plant tissues. The results of diaminobenzidine (DAB) and nitroblue tetrazolium (NBT) staining showed that XZ16 had significantly lower H2O2 and O2− concentrations than a salt-sensitive cultivar Gairdner, suggesting that the salt-tolerant genotype suffer from less oxidative damage. Moreover, XZ16 and Gairdner had the highest and lowest anti-oxidative enzyme activities and proline content in plant tissues. In addition, the microscopic examination revealed that DNA damage in cv. Gairdner was closely correlated to oxidative stress, representing that more reactive oxygen species accumulation in plants tissues leads to subsequent DNA damage. The present results show that higher salt tolerance of wild barley XZ16 is attributed to less Na+ accumulation and stronger anti-oxidative capacity.

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Mechanistic Insights into Potassium-Conferred Drought Stress Tolerance in Cultivated and Tibetan Wild Barley: Differential Osmoregulation, Nutrient Retention, Secondary Metabolism and Antioxidative Defense Capacity

International Journal of Molecular Sciences ◽

10.3390/ijms222313100 ◽

2021 ◽

Vol 22 (23) ◽

pp. 13100

Author(s):

Shafaque Sehar ◽

Muhammad Faheem Adil ◽

Muhammad Zeeshan ◽

Paul Holford ◽

Fangbin Cao ◽

...

Keyword(s):

Drought Stress ◽

Wild Barley ◽

Turgor Pressure ◽

Nutrient Retention ◽

Photosynthetic Parameters ◽

Chlorophyll Contents ◽

Tibetan Wild Barley ◽

Drought Tolerant ◽

Activity Enhancement ◽

Barley Genotypes

Keeping the significance of potassium (K) nutrition in focus, this study explores the genotypic responses of two wild Tibetan barley genotypes (drought tolerant XZ5 and drought sensitive XZ54) and one drought tolerant barley cv. Tadmor, under the exposure of polyethylene glycol-induced drought stress. The results revealed that drought and K deprivation attenuated overall plant growth in all the tested genotypes; however, XZ5 was least affected due to its ability to retain K in its tissues which could be attributed to the smallest reductions of photosynthetic parameters, relative chlorophyll contents and the lowest Na+/K+ ratios in all treatments. Our results also indicate that higher H+/K+-ATPase activity (enhancement of 1.6 and 1.3-fold for shoot; 1.4 and 2.5-fold for root), higher shoot K+ (2 and 2.3-fold) and Ca2+ content (1.5 and 1.7-fold), better maintenance of turgor pressure by osmolyte accumulation and enhanced antioxidative performance to scavenge ROS, ultimately suppress lipid peroxidation (in shoots: 4% and 35%; in roots 4% and 20% less) and bestow higher tolerance to XZ5 against drought stress in comparison with Tadmor and XZ54, respectively. Conclusively, this study adds further evidence to support the concept that Tibetan wild barley genotypes that utilize K efficiently could serve as a valuable genetic resource for the provision of genes for improved K metabolism in addition to those for combating drought stress, thereby enabling the development of elite barley lines better tolerant of abiotic stresses.

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Genome-Wide Identification and Characterization of Drought Stress Responsive microRNAs in Tibetan Wild Barley

International Journal of Molecular Sciences ◽

10.3390/ijms21082795 ◽

2020 ◽

Vol 21 (8) ◽

pp. 2795

Author(s):

Cheng-Wei Qiu ◽

Li Liu ◽

Xue Feng ◽

Peng-Fei Hao ◽

Xiaoyan He ◽

...

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Target Genes ◽

Wild Barley ◽

Expression Profiles ◽

Tibetan Wild Barley ◽

Drought Tolerant ◽

Genome Wide ◽

Barley Genotypes

Drought stress is a major obstacle to agricultural production. Tibetan wild barley with rich genetic diversity is useful for drought-tolerant improvement of cereals. MicroRNAs (miRNAs) play critical roles in controlling gene expression in response to various environment perturbations in plants. However, the genome-wide expression profiles of miRNAs and their targets in response to drought stress are largely unknown in wild barley. In this study, a polyethylene glycol (PEG) induced drought stress hydroponic experiment was performed, and the expression profiles of miRNAs from the roots of two contrasting Tibetan wild barley genotypes XZ5 (drought-tolerant) and XZ54 (drought-sensitive), and one cultivated barley Tadmor (drought-tolerant) generated by high-throughput sequencing were compared. There were 69 conserved miRNAs and 1574 novel miRNAs in the dataset of three genotypes under control and drought conditions. Among them, seven conserved miRNAs and 36 novel miRNAs showed significantly genotype-specific expression patterns in response to drought stress. And 12 miRNAs were further regarded as drought tolerant associated miRNAs in XZ5, which mostly participate in gene expression, metabolism, signaling and transportation, suggesting that they and their target genes play important roles in plant drought tolerance. This is the first comparation study on the miRNA transcriptome in the roots of two Tibetan wild barley genotypes differing in drought tolerance and one drought tolerant cultivar in response to PEG treatment. Further results revealed the candidate drought tolerant miRNAs and target genes in the miRNA regulation mechanism in wild barley under drought stress. Our findings provide valuable understandings for the functional characterization of miRNAs in drought tolerance.

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Variable Effects of Silicon on Salt Tolerant Indices in Rice Genotypes at Seedling Stage

Current Journal of Applied Science and Technology ◽

10.9734/cjast/2020/v39i2830937 ◽

2020 ◽

pp. 43-55

Author(s):

Rinny Swain ◽

Surabhika Panda ◽

Gyana Ranjan Rout

Keyword(s):

Salt Tolerance ◽

Salinity Stress ◽

Antioxidant Activities ◽

Principal Component ◽

Seedling Stage ◽

Antioxidant Enzyme Activities ◽

Salt Tolerant ◽

Silicon Accumulation ◽

Rice Genotypes ◽

Tolerance Indices

Silicon (Si) is known to improve salt tolerance in rice. However, the correlation of silicon with different physiological and biochemical indices of salt tolerance is not properly understood. Two rice genotypes with different silicon accumulation ability were evaluated along with two standard checks in response to 10 dS/m salinity stress (NaCl) and external Si source (1mM) during their seedling stage. All evaluated genotypes showed an evident decrease in biomass and chlorophyll content under salinity stress, while reporting an enhances in Si accumulation, Na+/K+ ratio, proline, electrolyte leakage, lipid peroxidation, hydrogen peroxide, and antioxidant activities. The external Si supplementation significantly improved rice tolerance to salinity through increased Si content, low Na+/K+ ratio, better osmolyte production, reduced membrane permeability, and improved antioxidant enzyme activities. Multivariate factor analysis with principal component factor statistically correlates and visualizes silicon accumulation with salt tolerance indices. The Hierarchical clustering in rice obtained based on the study of salt tolerance indices, distinguishes genotypes with different treatments into three clusters. In conclusion, the clustering grouped salt-tolerant Var.Lunishree and salt stress high silicon accumulating Var.Swarna together validates silicon mitigating effect on salinity in rice.

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Functional examination of lncRNAs in allotetraploid Gossypium hirsutum

BMC Genomics ◽

10.1186/s12864-021-07771-3 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Luyao Wang ◽

Jin Han ◽

Kening Lu ◽

Menglin Li ◽

Mengtao Gao ◽

...

Keyword(s):

Abiotic Stresses ◽

Expression Patterns ◽

Leaf Tissue ◽

Evolutionary Model ◽

Cotton Leaf ◽

Functional Screening ◽

Virus Induced Gene Silencing ◽

Individual Gene ◽

Cotton Species ◽

Allotetraploid Cotton

Abstract Background An evolutionary model using diploid and allotetraploid cotton species identified 80 % of non-coding transcripts in allotetraploid cotton as being uniquely activated in comparison with its diploid ancestors. The function of the lncRNAs activated in allotetraploid cotton remain largely unknown. Results We employed transcriptome analysis to examine the relationship between the lncRNAs and mRNAs of protein coding genes (PCGs) in cotton leaf tissue under abiotic stresses. LncRNA expression was preferentially associated with that of the flanking PCGs. Selected highly-expressed lncRNA candidates (n = 111) were subjected to a functional screening pilot test in which virus-induced gene silencing was integrated with abiotic stress treatment. From this low-throughput screen, we obtained candidate lncRNAs relating to plant height and tolerance to drought and other abiotic stresses. Conclusions Low-throughput screen is an effective method to find functional lncRNA for further study. LncRNAs were more active in abiotic stresses than PCG expression, especially temperature stress. LncRNA XLOC107738 may take a cis-regulatory role in response to environmental stimuli. The degree to which lncRNAs are constitutively expressed may impact expression patterns and functions on the individual gene level rather than in genome-wide aggregate.

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Genotypic Difference in the Responses to Nitrogen Fertilizer Form in Tibetan Wild and Cultivated Barley

Plants ◽

10.3390/plants10030595 ◽

2021 ◽

Vol 10 (3) ◽

pp. 595

Author(s):

Shama Naz ◽

Qiufang Shen ◽

Jonas Lwalaba Wa Lwalaba ◽

Guoping Zhang

Keyword(s):

Wild Barley ◽

Growth Parameters ◽

Inorganic Nitrogen ◽

N Uptake ◽

Total Soluble Protein ◽

Organic N ◽

Genotypic Difference ◽

N Availability ◽

Tibetan Wild Barley ◽

Cultivated Barley

Nitrogen (N) availability and form have a dramatic effect on N uptake and assimilation in plants, affecting growth and development. In the previous studies, we found great differences in low-N tolerance between Tibetan wild barley accessions and cultivated barley varieties. We hypothesized that there are different responses to N forms between the two kinds of barleys. Accordingly, this study was carried out to determine the response of four barley genotypes (two wild, XZ16 and XZ179; and two cultivated, ZD9 andHua30) under 4Nforms (NO3−, NH4+, urea and glycine). The results showed significant reduction in growth parameters such as root/shoot length and biomass, as well as photosynthesis parameters and total soluble protein content under glycine treatment relative to other N treatments, for both wild and cultivated barley, however, XZ179 was least affected. Similarly, ammonium adversely affected growth parameters in both wild and cultivated barleys, with XZ179 being severely affected. On the other hand, both wild and cultivated genotypes showed higher biomass, net photosynthetic rate, chlorophyll and protein in NO3− treatment relative to other three N treatments. It may be concluded that barley undisputedly grows well under inorganic nitrogen (NO3−), however in response to the organic N wild barley prefer glycine more than cultivated barely.

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