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Metabolic Responses of Plants to Abiotic Stress

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A special issue of Metabolites (ISSN 2218-1989). This special issue belongs to the section "Plant Metabolism".

Deadline for manuscript submissions: closed (15 July 2024) | Viewed by 13699

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Prof. Dr. Baoguo Du

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Guest Editor

1. College of Life Science and Biotechnology, Mianyang Normal University, Mianyang 621000, China
2. Faculty of Environment and Natural Resources, University of Freiburg, 79110 Freiburg, Germany
Interests: tree physiology; plant stress physiology; plant metabolomics; plant nitrogen metabolism; drought stress
Special Issues, Collections and Topics in MDPI journals

Dr. Youjun Zhang

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Guest Editor

Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam, Germany
Interests: metabolon; GC-MS; plant TCA cycle; plant mitochondrial metabolic engineering; plant synthetic biology; plant protein-protein interaction

Special Issue Information

Dear Colleagues,

Under the projected trajectory of climate change, plants are facing various abiotic stresses, e.g., drought, heat, flooding, UV and ozone pollution, and nutrient deficiency. Plants have evolved a diverse array of highly sophisticated mechanisms to respond to a wide range of environmental changes, including the biosynthesis, transport, and storage of primary and secondary metabolites, from the cell to the organ and to the whole plant level. Although the metabolic stress response has long been a hot topic in plant science, attracting much interest, it is still far from being elucidated.

The aim of this Special Issue is to attract review and original research papers on all aspects of plant stress biology, including on stomatal control, ROS, and antioxidants, with regard to primary and secondary metabolism under various climatic conditions. Particularly, manuscripts dedicated to exploring the complicated metabolic regulation system of plants with the means of omics are strongly encouraged. Manuscripts aiming to elucidate a certain class of compounds, for instance, nonstructural carbohydrates, amino acids, phosphorus, lignin, etc., in response to abiotic stress are also highly welcome. Furthermore, this Special Issue is not limited to plant stress biology, as research articles dealing with epigenetic regulation and long-term memory effects of abiotic stress will absolutely be considered.

Prof. Dr. Baoguo Du
Dr. Youjun Zhang
Guest Editors

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Keywords

climate change
abiotic stress
carbohydrates
nitrogen metabolism
metabolomics
ROS and antioxidants
memory effects
secondary metabolites
epigenetic regulations

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Published Papers (10 papers)

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Research

13 pages, 2717 KiB

Open AccessArticle

A Preliminary Study on the Whole-Plant Regulations of the Shrub Campylotropis polyantha in Response to Hostile Dryland Conditions

by Hua Zhang, Xue Jiang, Lijun Zhu, Lei Liu, Zhengqiao Liao and Baoguo Du

Metabolites 2024, 14(9), 495; https://doi.org/10.3390/metabo14090495 - 13 Sep 2024

Viewed by 485

Abstract

Drylands cover more than 40% of global land surface and will continue to expand by 10% at the end of this century. Understanding the resistance mechanisms of native species is of particular importance for vegetation restoration and management in drylands. In the present study, metabolome of a dominant shrub Campylotropis polyantha in a dry-hot valley were investigated. Compared to plants grown at the wetter site, C. polyantha tended to slow down carbon (C) assimilation to prevent water loss concurrent with low foliar reactive oxygen species and sugar concentrations at the drier and hotter site. Nitrogen (N) assimilation and turn over were stimulated under stressful conditions and higher leaf N content was kept at the expense of root N pools. At the drier site, roots contained more water but less N compounds derived from the citric acid cycle. The site had little effect on metabolites partitioning between leaves and roots. Generally, roots contained more C but less N. Aromatic compounds were differently impacted by site conditions. The present study, for the first time, uncovers the apparent metabolic adaptations of C. polyantha to hostile dryland conditions. However, due to the limited number of samples, we are cautious about drawing general conclusions regarding the resistance mechanisms. Further studies with a broader spatial range and larger time scale are therefore recommended to provide more robust information for vegetation restoration and management in dryland areas under a changing climate. Full article

(This article belongs to the Special Issue Metabolic Responses of Plants to Abiotic Stress)

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17 pages, 3811 KiB

Open AccessEditor’s ChoiceArticle

Comparison of Growth and Metabolomic Profiles of Two Afforestation Cypress Species Cupressus chengiana and Platycladus orientalis Grown at Minjiang Valley in Southwest China

by Zhengqiao Liao, Lijun Zhu, Lei Liu, Jürgen Kreuzwieser, Christiane Werner and Baoguo Du

Metabolites 2024, 14(8), 453; https://doi.org/10.3390/metabo14080453 - 17 Aug 2024

Cited by 1 | Viewed by 491

Abstract

In recent years, afforestation has been conducted in China’s hot and dry valleys. However, there is still a paucity of knowledge regarding the performance of tree species in these semi-arid regions, particularly with regard to interspecies differences. The present study compares the growth and metabolome characteristics of two widely used cypress species, namely Cupressus chengiana and Platycladus orientalis, grown at two sites with distinct climate conditions in the hot and dry Minjiang Valley in southwestern China. The findings indicate that C. chengiana trees exhibit superior growth rates compared to P. orientalis trees at both study sites. In comparison to P. orientalis trees, C. chengiana trees demonstrated a greater tendency to close their stomata in order to prevent water loss at the hotter and drier site, Llianghekou (LHK). Additionally, C. chengiana trees exhibited significantly lower hydrogen peroxide levels than P. orientalis trees, either due to lower production and/or higher scavenging of reactive oxygen species. C. chengiana trees accumulated soluble sugars as well as sugar derivatives, particularly those involved in sucrose and galactose metabolisms under stressful conditions. The species-specific differences were also reflected in metabolites involved in the tricarboxylic acid cycle, nitrogen, and secondary metabolisms. The metabolome profiles of the two species appeared to be influenced by the prevailing climatic conditions. It appeared that the trees at the drier and hotter site, LHK, were capable of efficient nitrogen uptake from the soil despite the low soil nitrogen concentration. This study is the first to compare the growth performance and metabolic profiles of two widely used tree species with high resistance to adverse conditions. In addition to the species-specific differences and adaptations to different sites, the present study also provides insights into potential management strategies to alleviate abiotic stress, particularly with regard to nitrogen nutrients, in the context of climate change. Full article

(This article belongs to the Special Issue Metabolic Responses of Plants to Abiotic Stress)

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21 pages, 3035 KiB

Open AccessEditor’s ChoiceArticle

Phenylpropanoid Metabolism in Phaseolus vulgaris during Growth under Severe Drought

by Luis Eduardo Peña Barrena, Lili Mats, Hugh J. Earl and Gale G. Bozzo

Metabolites 2024, 14(6), 319; https://doi.org/10.3390/metabo14060319 - 31 May 2024

Cited by 1 | Viewed by 851

Abstract

Drought limits the growth and development of Phaseolus vulgaris L. (known as common bean). Common bean plants contain various phenylpropanoids, but it is not known whether the levels of these metabolites are altered by drought. Here, BT6 and BT44, two white bean recombinant inbred lines (RILs), were cultivated under severe drought. Their respective growth and phenylpropanoid profiles were compared to those of well-irrigated plants. Both RILs accumulated much less biomass in their vegetative parts with severe drought, which was associated with more phaseollin and phaseollinisoflavan in their roots relative to well-irrigated plants. A sustained accumulation of coumestrol was evident in BT44 roots with drought. Transient alterations in the leaf profiles of various phenolic acids occurred in drought-stressed BT6 and BT44 plants, including the respective accumulation of two separate caftaric acid isomers and coutaric acid (isomer 1) relative to well-irrigated plants. A sustained rise in fertaric acid was observed in BT44 with drought stress, whereas the greater amount relative to well-watered plants was transient in BT6. Apart from kaempferol diglucoside (isomer 2), the concentrations of most leaf flavonol glycosides were not altered with drought. Overall, fine tuning of leaf and root phenylpropanoid profiles occurs in white bean plants subjected to severe drought. Full article

(This article belongs to the Special Issue Metabolic Responses of Plants to Abiotic Stress)

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19 pages, 4214 KiB

Open AccessArticle

Transcriptomic and Lipidomic Analysis Reveals Complex Regulation Mechanisms Underlying Rice Roots’ Response to Salt Stress

by Yingbin Xue, Chenyu Zhou, Naijie Feng, Dianfeng Zheng, Xuefeng Shen, Gangshun Rao, Yongxiang Huang, Wangxiao Cai, Ying Liu and Rui Zhang

Metabolites 2024, 14(4), 244; https://doi.org/10.3390/metabo14040244 - 21 Apr 2024

Viewed by 1498

Abstract

Rice (Oryza sativa L.), a crucial food crop that sustains over half the world’s population, is often hindered by salt stress during various growth stages, ultimately causing a decrease in yield. However, the specific mechanism of rice roots’ response to salt stress remains largely unknown. In this study, transcriptomics and lipidomics were used to analyze the changes in the lipid metabolism and gene expression profiles of rice roots in response to salt stress. The results showed that salt stress significantly inhibited rice roots’ growth and increased the roots’ MDA content. Furthermore, 1286 differentially expressed genes including 526 upregulated and 760 downregulated, were identified as responding to salt stress in rice roots. The lipidomic analysis revealed that the composition and unsaturation of membrane lipids were significantly altered. In total, 249 lipid molecules were differentially accumulated in rice roots as a response to salt stress. And most of the major phospholipids, such as phosphatidic acid (PA), phosphatidylcholine (PC), and phosphatidylserine (PS), as well as major sphingolipids including ceramide (Cer), phytoceramide (CerP), monohexose ceramide (Hex1Cer), and sphingosine (SPH), were significantly increased, while the triglyceride (TG) molecules decreased. These results suggested that rice roots mitigate salt stress by altering the fluidity and integrity of cell membranes. This study enhances our comprehension of salt stress, offering valuable insights into changes in the lipids and adaptive lipid remodeling in rice’s response to salt stress. Full article

(This article belongs to the Special Issue Metabolic Responses of Plants to Abiotic Stress)

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14 pages, 2611 KiB

Open AccessArticle

Salicylic Acid and Water Stress: Effects on Morphophysiology and Essential Oil Profile of Eryngium foetidum

by Sabrina Kelly dos Santos, Daniel da Silva Gomes, Vanessa de Azevedo Soares, Estephanni Fernanda Oliveira Dantas, Ana Flávia Pellegrini de Oliveira, Moises Henrique Almeida Gusmão, Elyabe Monteiro de Matos, Tancredo Souza, Lyderson Facio Viccini, Richard Michael Grazul, Juliane Maciel Henschel and Diego Silva Batista

Metabolites 2024, 14(4), 241; https://doi.org/10.3390/metabo14040241 - 21 Apr 2024

Viewed by 1072

Abstract

The exogenous application of bioregulators, such as salicylic acid (SA), has exhibited promising outcomes in alleviating drought stress. Nevertheless, its impact on culantro (Eryngium foetidum L.) remains unexplored. Thus, the aim of this study was to assess how SA impacts the growth, morphophysiology, and essential oil composition of culantro when subjected to drought. To achieve this, culantro plants were grown under three different watering regimes: well-watered, drought-stressed, and re-watered. Additionally, they were either treated with SA (100 µM) or left untreated, with water serving as the control. SA application did not mitigate the effects of drought in biomass production but increased biomass, leaf number, leaf area, and photosynthetic pigments under well-irrigated and re-watered conditions. After a drought period followed by re-watering, plants recovered membrane integrity independently of SA application. Water stress and the exogenous application of SA also modulated the profile of essential oils. This is the first report about SA and drought affecting growth and essential oil composition in culantro. Full article

(This article belongs to the Special Issue Metabolic Responses of Plants to Abiotic Stress)

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15 pages, 1713 KiB

Open AccessArticle

Effect of Low Temperature on Content of Primary Metabolites in Two Wheat Genotypes Differing in Cold Tolerance

by Alexander Deryabin, Kseniya Zhukova, Natalia Naraikina and Yuliya Venzhik

Metabolites 2024, 14(4), 199; https://doi.org/10.3390/metabo14040199 - 3 Apr 2024

Viewed by 1350

Abstract

The study of cold-tolerance mechanisms of wheat as a leading cereal crop is very relevant to science. Primary metabolites play an important role in the formation of increased cold tolerance. The aim of this research is to define changes in the content of primary metabolites (soluble proteins and sugars), growth, and photosynthetic apparatus of freezing-tolerant and cold-sustainable wheat (Triticum aestivum L.) genotypes under optimal conditions and after prolonged (7 days) exposure to low temperature (4 °C). In order to gain a deeper comprehension of the mechanisms behind wheat genotypes’ adaptation to cold, we determined the expression levels of photosynthetic genes (RbcS, RbcL) and genes encoding cold-regulated proteins (Wcor726, CBF14). The results indicated different cold-adaptation strategies of freezing-tolerant and cold-sustainable wheat genotypes, with soluble proteins and sugars playing a significant role in this process. In plants of freezing-tolerant genotypes, the strategy of adaptation to low temperature was aimed at increasing the content of soluble proteins and modification of carbohydrate metabolism. The accumulation of sugars was not observed in wheat of cold-sustainable genotypes during chilling, but a high content of soluble proteins was maintained both under optimal conditions and after cold exposure. The adaptation strategies of wheat genotypes differing in cold tolerance were related to the expression of photosynthetic genes and genes encoding cold-regulated proteins. The data improve our knowledge of physiological and biochemical mechanisms of wheat cold adaptation. Full article

(This article belongs to the Special Issue Metabolic Responses of Plants to Abiotic Stress)

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22 pages, 9615 KiB

Open AccessArticle

5-ALA, DTA-6, and Nitrogen Mitigate NaCl Stress by Promoting Photosynthesis and Carbon Metabolism in Rice Seedlings

by Yaxin Wang, Chaolu Tan, Yinghao Li, Fengyan Meng, Youwei Du, Shuyu Zhang, Wenxin Jiang, Naijie Feng, Liming Zhao and Dianfeng Zheng

Metabolites 2024, 14(3), 142; https://doi.org/10.3390/metabo14030142 - 27 Feb 2024

Cited by 2 | Viewed by 1502

Abstract

A large number of dead seedlings can occur in saline soils, which seriously affects the large-scale cultivation of rice. This study investigated the effects of plant growth regulators (PGRs) and nitrogen application on seedling growth and salt tolerance (Oryza sativa L.), which is of great significance for agricultural production practices. A conventional rice variety, “Huang Huazhan”, was selected for this study. Non-salt stress treatments included 0% NaCl (CK treatment), CK + 0.05 g N/pot (N treatment), CK + 40 mg·L⁻¹ 5-aminolevulinic acid (5-ALA) (A treatment), and CK + 30 mg·L⁻¹ diethylaminoethyl acetate (DTA-6) (D treatment). Salt stress treatments included 0.3% NaCl (S treatment), N + 0.3% NaCl (NS treatment), A + 0.3% NaCl (AS treatment), and D + 0.3% NaCl (DS treatment). When 3 leaves and 1 heart emerged from the soil, plants were sprayed with DTA-6 and 5-ALA, followed by the application of 0.3% NaCl (w/w) to the soil after 24 h. Seedling morphology and photosynthetic indices, as well as carbohydrate metabolism and key enzyme activities, were determined for each treatment. Our results showed that N, A, and D treatments promoted seedling growth, photosynthesis, carbohydrate levels, and the activities of key enzymes involved in carbon metabolism when compared to the CK treatment. The A treatment had the most significant effect, with increases in aboveground dry weight and net photosynthetic rates (Pn) ranging from 17.74% to 41.02% and 3.61% to 32.60%, respectively. Stomatal limiting values (Ls) significantly decreased from 19.17% to 43.02%. Salt stress significantly inhibited seedling growth. NS, AS, and DS treatments alleviated the morphological and physiological damage of salt stress on seedlings when compared to the S treatment. The AS treatment was the most effective in improving seedling morphology, promoting photosynthesis, increasing carbohydrate levels, and key enzyme activities. After AS treatment, increases in aboveground dry weight, net photosynthetic rate, soluble sugar content, total sucrose synthase, and amylase activities were 17.50% to 50.79%, 11.39% to 98.10%, 20.20% to 80.85%, 21.21% to 33.53%, and 22.17% to 34.19%, respectively, when compared to the S treatment. In summary, foliar sprays of 5-ALA, DTA-6, and additional nitrogen fertilizer enhanced rice seedling growth, increased photosynthesis, lowered Ls values, and improved seedling salt tolerance. Spraying two regulators, 5-ALA and DTA-6, quantitatively increased the effect of nitrogen fertilizer, with comparable effects on NaCl stress regulation. This study provides the basis for efficient agricultural production. Full article

(This article belongs to the Special Issue Metabolic Responses of Plants to Abiotic Stress)

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15 pages, 1478 KiB

Open AccessArticle

Transcriptomic Analysis Reveals the Response Mechanisms of Bell Pepper (Capsicum annuum) to Phosphorus Deficiency

by Daizha Salazar-Gutiérrez, Abraham Cruz-Mendívil, Claudia Villicaña, José Basilio Heredia, Luis Alberto Lightbourn-Rojas and Josefina León-Félix

Metabolites 2023, 13(10), 1078; https://doi.org/10.3390/metabo13101078 - 13 Oct 2023

Cited by 1 | Viewed by 1598

Abstract

Phosphorus (P) is an important nutritional element needed by plants. Roots obtain P as inorganic phosphate (Pi), mostly in H₂PO⁻₄ form. It is vital for plants to have a sufficient supply of Pi since it participates in important processes like photosynthesis, energy transfer, and protein activation, among others. The physicochemical properties and the organic material usually make Pi bioavailability in soil low, causing crops and undomesticated plants to experience variations in accessibility or even a persistent phosphate limitation. In this study, transcriptome data from pepper roots under low-Pi stress was analyzed in order to identify Pi starvation-responsive genes and their relationship with metabolic pathways and functions. Transcriptome data were obtained from pepper roots with Pi deficiency by RNASeq and analyzed with bioinformatic tools. A total of 97 differentially expressed genes (DEGs) were identified; Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment revealed that metabolic pathways, such as porphyrin and chlorophyll metabolism, were down-regulated, and galactose and fatty acid metabolism were up-regulated. The results indicate that bell pepper follows diverse processes related to low Pi tolerance regulation, such as the remobilization of internal Pi, alternative metabolic pathways to generate energy, and regulators of root development. Full article

(This article belongs to the Special Issue Metabolic Responses of Plants to Abiotic Stress)

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14 pages, 3352 KiB

Open AccessArticle

Influence of High-Temperature and Intense Light on the Enzymatic Antioxidant System in Ginger (Zingiber officinale Roscoe) Plantlets

by Min Gong, Dongzhu Jiang, Ran Liu, Shuming Tian, Haitao Xing, Zhiduan Chen, Rujie Shi and Hong-Lei Li

Metabolites 2023, 13(9), 992; https://doi.org/10.3390/metabo13090992 - 4 Sep 2023

Cited by 6 | Viewed by 1512

Abstract

Environmental stressors such as high temperature and intense light have been shown to have negative effects on plant growth and productivity. To survive in such conditions, plants activate several stress response mechanisms. The synergistic effect of high-temperature and intense light stress has a significant impact on ginger, leading to reduced ginger production. Nevertheless, how ginger responds to this type of stress is not yet fully understood. In this study, we examined the phenotypic changes, malonaldehyde (MDA) content, and the response of four vital enzymes (superoxide dismutase (SOD), catalase (CAT), lipoxygenase (LOX), and nitrate reductase (NR)) in ginger plants subjected to high-temperature and intense light stress. The findings of this study indicate that ginger is vulnerable to high temperature and intense light stress. This is evident from the noticeable curling, yellowing, and wilting of ginger leaves, as well as a decrease in chlorophyll index and an increase in MDA content. Our investigation confirms that ginger plants activate multiple stress response pathways, including the SOD and CAT antioxidant defenses, and adjust their response over time by switching to different pathways. Additionally, we observe that the expression levels of genes involved in different stress response pathways, such as SOD, CAT, LOX, and NR, are differently regulated under stress conditions. These findings offer avenues to explore the stress mechanisms of ginger in response to high temperature and intense light. They also provide interesting information for the choice of genetic material to use in breeding programs for obtaining ginger genotypes capable of withstanding high temperatures and intense light stress. Full article

(This article belongs to the Special Issue Metabolic Responses of Plants to Abiotic Stress)

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15 pages, 1470 KiB

Open AccessArticle

Effects of Storage Temperature at the Early Postharvest Stage on the Firmness, Bioactive Substances, and Amino Acid Compositions of Chili Pepper (Capsicum annuum L.)

by Yuan Cheng, Chengan Gao, Shaodan Luo, Zhuping Yao, Qingjing Ye, Hongjian Wan, Guozhi Zhou and Chaochao Liu

Metabolites 2023, 13(7), 820; https://doi.org/10.3390/metabo13070820 - 5 Jul 2023

Cited by 5 | Viewed by 1690

Abstract

The commercial and nutritional quality of chili peppers deteriorates rapidly after harvest. So far, little is known about the effect of temperature on postharvest chili pepper quality. This study elucidated the effects of two temperatures (20 °C and 30 °C) on chili peppers’ postharvest firmness, flavor, and nutritional attributes. We found that compared to 20 °C, 30 °C escalated the decline in fruit firmness, capsaicin content, and dihydrocapsaicin content, while enhancing the increment in water loss and electrical conductivity, as well as total carotenoids and ascorbic acid content. The contents of most amino acids (AAs) decreased significantly during postharvest storage compared to their initial values, whether stored at 20 °C or 30 °C; however, 30 °C had a more substantial impact than 20 °C. Meanwhile, as for soluble protein and amino acid compositions, the effect of storage temperature was genotype-dependent, as reflected by differential changes in total AA contents, single AA contents, essential AA ratio, delicious AA ratio, etc., under the 20 °C or 30 °C treatments. In conclusion, our findings reveal the influence of temperature on pepper quality, showing that the storage temperature of 20 °C was better for maintaining chili quality than 30 °C from the perspective of overall commercial attributes. Full article

(This article belongs to the Special Issue Metabolic Responses of Plants to Abiotic Stress)

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