Contents of lobetyolin, syringin, and atractylolide III in Codonopsis pilosula are related to dynamic changes of endophytes under drought stress

Abstract Background Codonopsis pilosula, an important medicinal plant, can accumulate certain metabolites under moderate drought stress. Endophytes are involved in the metabolite accumulations within medicinal plants. It is still unknown that the endophytes of C. pilosula are associated with the accumulations of metabolites. This study aims to investigate the promoting effect of endophytes on the accumulations of active substances in C. pilosula under drought stress. Methods High–performance liquid chromatography and high–throughput sequencing technology were performed to investigate changes in the contents of secondary metabolite and endophyte abundances of C. pilosula under drought stress, respectively. Spearman’s correlation analysis was further conducted to identify the endophytic biomarkers related to accumulations of pharmacodynamic compounds. Culture-dependent experiments were performed to confirm the functions of endophytes in metabolite accumulations. Results The distribution of pharmacological components and diversity and composition of endophytes showed tissue specificity within C. pilosula. The contents of lobetyolin, syringin, and atractylolide III in C. pilosula under drought stress were increased by 8.47%‒86.47%, 28.78%‒230.98%, and 32.17%‒177.86%, respectively, in comparison with those in untreated groups. The Chao 1 and Shannon indices in different parts of drought–stressed C. pilosula increased compared with those in untreated parts. The composition of endophytic communities in drought treatment parts of C. pilosula was different from that in control parts. A total of 226 microbial taxa were identified as potential biomarkers, of which the abundances of 42 taxa were significantly and positively correlated to the pharmacodynamic contents. Culture-dependent experiments confirmed that the contents of lobetyolin and atractylolide III were increased by the application of Epicoccum thailandicum, Filobasidium magnum, and Paraphoma rhaphiolepidis at the rates of 11.12%‒46.02%, and that the content of syringin was increased by Pseudomonas nitroreducens at the rates of 118.61%‒119.36%. Conclusions Certain endophytes participated in the accumulations of bioactive metabolites, which provided a scientific evidence for the development and application of microorganisms to improve the quality of traditional Chinese medicine.

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Uncovering fungal community composition in natural habitat of Ophiocordyceps sinensis using high-throughput sequencing and culture-dependent approaches

10.21203/rs.3.rs-28393/v1 ◽

2020 ◽

Author(s):

Chuanbo Zhang ◽

Chao-Hui Ren ◽

Yan-Li Wang ◽

Qi-Qi Wang ◽

Yun-Sheng Wang ◽

...

Keyword(s):

Community Structure ◽

High Throughput ◽

Fungal Community ◽

High Throughput Sequencing ◽

Fungal Communities ◽

Bioactive Metabolites ◽

Fungal Community Structure ◽

Ophiocordyceps Sinensis ◽

Culturable Fungi ◽

Culture Dependent

Abstract Background The fungal communities inhabiting natural Ophiocordyceps sinensis play critical ecological roles in alpine meadow ecosystem, contribute to infect host insect, influence the occurrence of O. sinensis, and are repertoire of potential novel metabolites discovery. However, a comprehensive understanding of fungal communities of O. sinensis remain elusive. Therefore, the present study aimed to unravel fungal communities of natural O. sinensis using combination of high-throughput sequencing and culture-dependent approach. Results A total of 280,519 high-quality sequences, belonging to 5 fungal phyla, 15 classes, 41 orders, 79 families, 112 genera, and 352 putative operational taxonomic units (OTUs) were obtained from natural O. sinensis using high-throughput sequencing. Among of which, 43 genera were identified in external mycelial cortices (EMC), Ophiocordyceps, Sebacinia, Archaeorhizomyces were predominant genera with the abundance of 95.86%, 1.14%, 0.85%, respectively. Total 66 genera were identified from soil microhabitat, Inocybe, Archaeorhizomyces, Unclassified Thelephoraceae, Tomentella, Thelephora, Sebacina, Unclassified Ascomycota, Unclassified Fungi were predominant genera with an average abundance of 53.32%, 8.69%, 8.12%, 8.12%, 7.21%, 4.6%, 3.08% and 3.05%, respectively. The fungal communities in external mycelial cortices (EMC) were significantly distinct from the soil microhabitat (Soil). Meanwhile, seven culture media that benefit for the growth of O. sinensis were used to isolate culturable fungi at 16 °C, resulted in 77 fungal strains isolated for rDNA ITS sequence analysis, belonging to 33 genera, including Ophiocordyceps, Trichoderma, Cytospora, Truncatella, Dactylonectria, Isaria, Cephalosporium, Fusarium, Cosmospora, Paecilomyces, etc.. Among all culturable fungi, Mortierella and Trichoderma were predominant genera of total isolates. Conclusions The significantly distinction and overlap in fungal community structure between two approaches highlight that integration of approaches would generate more information than either of them. Our finding is the first investigation of fungal community structure of natural O. sinensis by two approachs, provide new insight into O. sinensis associated fungi, and support that microbiota of O. sinensis is an untapped source for novel bioactive metabolites discovery.

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Morphological and Physiological Traits that Explain Yield Response to Drought Stress in Miscanthus

Agronomy ◽

10.3390/agronomy10081194 ◽

2020 ◽

Vol 10 (8) ◽

pp. 1194

Author(s):

Marta Malinowska ◽

Iain Donnison ◽

Paul Robson

Keyword(s):

Drought Stress ◽

Phenotypic Plasticity ◽

Perennial Grass ◽

Complex Model ◽

Stem Length ◽

Yield Response ◽

Genotypic Differences ◽

Drought Treatment ◽

Moderate Drought ◽

High Yields

Miscanthus is a high yielding perennial grass capable of high biomass yields with low inputs. Traits associated with yield have been identified in miscanthus, but less is known about the traits associated with sustaining biomass production under drought stress. The commercial hybrid M. × giganteus and high yielding examples from the parental species M. sinensis and M. sacchariflorus were grown under well-watered and moderate drought conditions. Growth, morphology, physiology and phenotypic plasticity were analyzed. Functional data were parameterized and a matrix of traits examined for associations with yield, genotype and drought treatment. Phenotypic plasticity was determined, indexes were then calculated to determine the plasticity of trait responses. All genotypes assessed responded to moderate drought stress, and genotypic differences in yield decreased under drought. Genotypes with low tolerance exhibited greater plasticity than highly drought tolerant M. sinensis. In well-watered plants variance in yield was explained by a relatively simple empirical model including stem length and stem number, whereas under drought a more complex model was needed including the addition of leaf area and stomatal conductance data. This knowledge can help us to define ideotypes for drought tolerance and develop miscanthus varieties that sustain high yields across a range of environmental conditions.

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Flavonoids improve drought tolerance of maize seedlings by regulating the homeostasis of reactive oxygen species

Plant and Soil ◽

10.1007/s11104-020-04814-8 ◽

2021 ◽

Author(s):

Baozhu Li ◽

Ruonan Fan ◽

Guiling Sun ◽

Ting Sun ◽

Yanting Fan ◽

...

Keyword(s):

Free Radicals ◽

Drought Stress ◽

Drought Tolerance ◽

Infrared Imaging ◽

Oxygen Free Radicals ◽

Transcriptome Profiling ◽

Far Infrared ◽

Drought Treatment ◽

Physiological Characterization ◽

Oxidative Damages

Abstract Background and aims As drought threatens the yield and quality of maize (Zea mays L.), it is important to dissect the molecular basis of maize drought tolerance. Flavonoids, participate in the scavenging of oxygen free radicals and alleviate stress-induced oxidative damages. This study aims to dissect the function of flavonoids in the improvement of maize drought tolerance. Methods Using far-infrared imaging screening, we previously isolated a drought overly insensitivity (doi) mutant from an ethyl methanesulfonate (EMS)-mutagenized maize library and designated it as doi57. In this study, we performed a physiological characterization and transcriptome profiling of doi57 in comparison to corresponding wild-type B73 under drought stress. Results Under drought stress, doi57 seedlings displayed lower leaf-surface temperature (LST), faster water loss, and better performance in growth than B73. Transcriptome analysis reveals that key genes involved in flavonoid biosynthesis are enriched among differentially expressed genes in doi57. In line with these results, more flavonols and less hydrogen peroxide (H2O2) were accumulated in guard cells of doi57 than in those of B73 with the decrease of soil water content (SWC). Moreover, the capacity determined from doi57 seedling extracts to scavenge oxygen free radicals was more effective than that of B73 under the drought treatment. Additionally, doi57 seedlings had higher photosynthetic rates, stomatal conductance, transpiration rates, and water use efficiency than B73 exposed to drought stress, resulting in high biomass and greater root/shoot ratios in doi57 mutant plants. Conclusion Flavonoids may facilitate maize seedling drought tolerance by lowering drought-induced oxidative damage as well regulating stomatal movement.

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Licorice (Glycyrrhiza glabra)—Growth and Phytochemical Compound Secretion in Degraded Lands under Drought Stress

Sustainability ◽

10.3390/su13052923 ◽

2021 ◽

Vol 13 (5) ◽

pp. 2923

Author(s):

Botir Khaitov ◽

Munisa Urmonova ◽

Aziz Karimov ◽

Botirjon Sulaymonov ◽

Kholik Allanov ◽

...

Keyword(s):

Drought Stress ◽

Water Deficit ◽

Background Field ◽

Field Trials ◽

Glycyrrhiza Glabra ◽

Agricultural System ◽

Positive Effects ◽

Relative Water ◽

Moderate Drought ◽

Four Levels

Water deficiency restricts plant productivity, while excessive soil moisture may also have an adverse impact. In light of this background, field trials were conducted in secondary saline soil (EC 6.5 dS m−1) at the experimental station of Tashkent State Agrarian University (TSAU), Uzbekistan to determine drought tolerance of licorice (Glycyrrhiza glabra) by exposure to four levels of water deficit, namely control (70–80%), moderate (50–60%), strong (30–40%) and intense (10–20%) relative water content (WC) in the soil. The moderate drought stress exhibited positive effects on the morphological and physiological parameters of licorice, and was considered to be the most suitable water regime for licorice cultivation. Plant growth under the 50–60% WC treatment was slightly higher as compared to 70–80% WC treatment, exhibiting weak water deficit promotes licorice growth, root yield and secondary metabolite production. In particular, secondary metabolites i.e., ash, glycyrrhizic acid, extractive compounds and flavonoids, tended to increase under moderate water deficit, however further drought intensification brought a sharp decline of these values. These results contribute to the development of licorice cultivation technologies in arid regions and the most important consideration is the restoration of ecological and economical functions of the dryland agricultural system.

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Comparing transcriptional responses to Fusarium crown rot in wheat and barley identified an important relationship between disease resistance and drought tolerance

BMC Plant Biology ◽

10.1186/s12870-020-02818-1 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Z. Y. Su ◽

J. J. Powell ◽

S. Gao ◽

M. Zhou ◽

C. Liu

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Crown Rot ◽

Differentially Expressed ◽

Transcriptional Responses ◽

Drought Treatment ◽

Crop Species ◽

Fusarium Crown Rot ◽

Important Relationship ◽

The Impact

Abstract Background Fusarium crown rot (FCR) is a chronic disease in cereal production worldwide. The impact of this disease is highly environmentally dependant and significant yield losses occur mainly in drought-affected crops. Results In the study reported here, we evaluated possible relationships between genes conferring FCR resistance and drought tolerance using two approaches. The first approach studied FCR induced differentially expressed genes (DEGs) targeting two barley and one wheat loci against a panel of genes curated from the literature based on known functions in drought tolerance. Of the 149 curated genes, 61.0% were responsive to FCR infection across the three loci. The second approach was a comparison of the global DEGs induced by FCR infection with the global transcriptomic responses under drought in wheat. This analysis found that approximately 48.0% of the DEGs detected one week following drought treatment and 74.4% of the DEGs detected three weeks following drought treatment were also differentially expressed between the susceptible and resistant isolines under FCR infection at one or more timepoints. As for the results from the first approach, the vast majority of common DEGs were downregulated under drought and expressed more highly in the resistant isoline than the sensitive isoline under FCR infection. Conclusions Results from this study suggest that the resistant isoline in wheat was experiencing less drought stress, which could contribute to the stronger defence response than the sensitive isoline. However, most of the genes induced by drought stress in barley were more highly expressed in the susceptible isolines than the resistant isolines under infection, indicating that genes conferring drought tolerance and FCR resistance may interact differently between these two crop species. Nevertheless, the strong relationship between FCR resistance and drought responsiveness provides further evidence indicating the possibility to enhance FCR resistance by manipulating genes conferring drought tolerance.

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Response of Bioactive Metabolite and Biosynthesis Related Genes to Methyl Jasmonate Elicitation in Codonopsis pilosula

Molecules ◽

10.3390/molecules24030533 ◽

2019 ◽

Vol 24 (3) ◽

pp. 533 ◽

Cited By ~ 8

Author(s):

Jiao-jiao Ji ◽

Qi Feng ◽

Hai-feng Sun ◽

Xue-jun Zhang ◽

Xiao-xiao Li ◽

...

Keyword(s):

Methyl Jasmonate ◽

Adventitious Roots ◽

Multiple Shoots ◽

Bioactive Metabolites ◽

Bioactive Metabolite ◽

Codonopsis Pilosula ◽

Meja Treatment ◽

Metabolite Accumulation ◽

Culture Growth ◽

Sucrose Level

Bioactive metabolites in Codonopsis pilosula are of particular interest as an immunostimulant. Methyl jasmonate (MeJA) plays an important role in the elicitation of metabolite biosynthesis. Here, we explored the response of metabolites to MeJA elicitation in C. pilosula adventitious roots and multiple shoots. The results showed that the biomass, polysaccharide, and lobetyolin content of adventitious roots exhibited the highest increases with 100 µmol·L−1 MeJA at the 16th day of subculture, whereas the atractylenolide III (a terpenoid) content increased extremely with 50 µmol·L−1 MeJA treatment at the 7th day of subculture. In addition, the biomass and lobetyolin content significantly increased at the 4th day after treatment. Similarly, the polysaccharide and lobetyolin content increased in multiple shoots. Further identification of different metabolites responding to MeJA by 1H-NMR showed an extremely significant increase of the lobetyolinin level, which coincided with lobetyolin. Accordingly, the precursor, fatty acids, showed a highly significant decrease in their levels. Furthermore, a significant increase in β-d-fructose-butanol glycoside was detected, which was accompanied by a decrease in the sucrose level. Accordingly, the enzyme genes responsible for terpenoid and carbohydrate biosynthesis, CpUGPase, and CpPMK, were up regulated. In conclusion, MeJA promoted culture growth and accelerated bioactive metabolite accumulation by regulating the expression of the metabolite biosynthesis related genes, CpUGPase and CpPMK in C. pilosula.

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Assessing Genotypic and Environmental Effects on Endophyte Communities of Fraxinus (Ash) Using Culture Dependent and Independent DNA Sequencing

Journal of Fungi ◽

10.3390/jof7070565 ◽

2021 ◽

Vol 7 (7) ◽

pp. 565

Author(s):

Anindita Lahiri ◽

Brian R. Murphy ◽

Trevor R. Hodkinson

Keyword(s):

Community Composition ◽

Environmental Effects ◽

High Throughput Sequencing ◽

Fungal Community Composition ◽

Species Identity ◽

Ash Dieback ◽

Hymenoscyphus Fraxineus ◽

Culture Independent ◽

The Impact ◽

Culture Dependent

Fraxinus excelsior populations are in decline due to the ash dieback disease Hymenoscyphus fraxineus. It is important to understand genotypic and environmental effects on its fungal microbiome to develop disease management strategies. To do this, we used culture dependent and culture independent approaches to characterize endophyte material from contrasting ash provenances, environments, and tissues (leaves, roots, seeds). Endophytes were isolated and identified using nrITS, LSU, or tef DNA loci in the culture dependent assessments, which were mostly Ascomycota and assigned to 37 families. Few taxa were shared between roots and leaves. The culture independent approach used high throughput sequencing (HTS) of nrITS amplicons directly from plant DNA and detected 35 families. Large differences were found in OTU diversity and community composition estimated by the contrasting approaches and these data need to be combined for estimations of the core endophyte communities. Species richness and Shannon index values were highest for the leaf material and the French population. Few species were shared between seed and leaf tissue. PCoA and NMDS of the HTS data showed that seed and leaf microbiome communities were highly distinct and that there was a strong influence of Fraxinus species identity on their fungal community composition. The results will facilitate a better understanding of ash fungal ecology and are a step toward identifying microbial biocontrol systems to minimize the impact of the disease.

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Discovery of MicroRNAs and Their Target Genes Related to Drought in Paulownia “Yuza 1” by High-Throughput Sequencing

International Journal of Genomics ◽

10.1155/2017/3674682 ◽

2017 ◽

Vol 2017 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Minjie Deng ◽

Yabing Cao ◽

Zhenli Zhao ◽

Lu Yang ◽

Yanfang Zhang ◽

...

Keyword(s):

Drought Stress ◽

Molecular Mechanisms ◽

High Throughput Sequencing ◽

Plant Hormone ◽

Target Genes ◽

Reference Data ◽

Relevant Information ◽

Putative Target

Understanding the role of miRNAs in regulating the molecular mechanisms responsive to drought stress was studied in Paulownia “yuza 1.” Two small RNA libraries and two degradome libraries were, respectively, constructed and sequenced in order to detect miRNAs and their target genes associated with drought stress. A total of 107 miRNAs and 42 putative target genes were identified in this study. Among them, 77 miRNAs were differentially expressed between drought-treated Paulownia “yuza 1” and the control (60 downregulated and 17 upregulated). The predicted target genes were annotated using the GO, KEGG, and Nr databases. According to the functional classification of the target genes, Paulownia “yuza 1” may respond to drought stress via plant hormone signal transduction, photosynthesis, and osmotic adjustment. Furthermore, the expression levels of seven miRNAs (ptf-miR157b, ptf-miR159b, ptf-miR398a, ptf-miR9726a, ptf-M2153, ptf-M2218, and ptf-M24a) and their corresponding target genes were validated by quantitative real-time PCR. The results provide relevant information for understanding the molecular mechanism of Paulownia resistance to drought and reference data for researching drought resistance of other trees.

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Wheat flag leaf epicuticular wax morphology and composition in response to moderate drought stress are revealed by SEM, FTIR-ATR and synchrotron X-ray spectroscopy

Physiologia Plantarum ◽

10.1111/ppl.12637 ◽

2017 ◽

Vol 162 (3) ◽

pp. 316-332 ◽

Cited By ~ 14

Author(s):

Ian R. Willick ◽

Rachid Lahlali ◽

Perumal Vijayan ◽

David Muir ◽

Chithra Karunakaran ◽

...

Keyword(s):

Drought Stress ◽

Flag Leaf ◽

Epicuticular Wax ◽

X Ray ◽

Moderate Drought ◽

Leaf Epicuticular Wax

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Comparative Proteomics of Root Apex and Root Elongation Zones Provides Insights into Molecular Mechanisms for Drought Stress and Recovery Adjustment in Switchgrass

Proteomes ◽

10.3390/proteomes8010003 ◽

2020 ◽

Vol 8 (1) ◽

pp. 3 ◽

Cited By ~ 2

Author(s):

Zhujia Ye ◽

Sasikiran Reddy Sangireddy ◽

Chih-Li Yu ◽

Dafeng Hui ◽

Kevin Howe ◽

...

Keyword(s):

Mass Spectrometry ◽

Drought Stress ◽

Molecular Mechanisms ◽

Root Zone ◽

Root Apex ◽

Root Tip ◽

Leaf Water Content ◽

Severe Drought ◽

Proteomics Data ◽

Drought Treatment

Switchgrass plants were grown in a Sandwich tube system to induce gradual drought stress by withholding watering. After 29 days, the leaf photosynthetic rate decreased significantly, compared to the control plants which were watered regularly. The drought-treated plants recovered to the same leaf water content after three days of re-watering. The root tip (1cm basal fragment, designated as RT1 hereafter) and the elongation/maturation zone (the next upper 1 cm tissue, designated as RT2 hereafter) tissues were collected at the 29th day of drought stress treatment, (named SDT for severe drought treated), after one (D1W) and three days (D3W) of re-watering. The tandem mass tags mass spectrometry-based quantitative proteomics analysis was performed to identify the proteomes, and drought-induced differentially accumulated proteins (DAPs). From RT1 tissues, 6156, 7687, and 7699 proteins were quantified, and 296, 535, and 384 DAPs were identified in the SDT, D1W, and D3W samples, respectively. From RT2 tissues, 7382, 7255, and 6883 proteins were quantified, and 393, 587, and 321 proteins DAPs were identified in the SDT, D1W, and D3W samples. Between RT1 and RT2 tissues, very few DAPs overlapped at SDT, but the number of such proteins increased during the recovery phase. A large number of hydrophilic proteins and stress-responsive proteins were induced during SDT and remained at a higher level during the recovery stages. A large number of DAPs in RT1 tissues maintained the same expression pattern throughout drought treatment and the recovery phases. The DAPs in RT1 tissues were classified in cell proliferation, mitotic cell division, and chromatin modification, and those in RT2 were placed in cell wall remodeling and cell expansion processes. This study provided information pertaining to root zone-specific proteome changes during drought and recover phases, which will allow us to select proteins (genes) as better defined targets for developing drought tolerant plants. The mass spectrometry proteomics data are available via ProteomeXchange with identifier PXD017441.

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