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Jin Y, Chen Z, White JF, Malik K, Li C. Interactions between Epichloë endophyte and the plant microbiome impact nitrogen responses in host Achnatherum inebrians plants. Microbiol Spectr 2024; 12:e0257423. [PMID: 38488391 PMCID: PMC10986526 DOI: 10.1128/spectrum.02574-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 01/24/2024] [Indexed: 04/06/2024] Open
Abstract
The clavicipitaceous fungus Epichloë gansuensis forms symbiotic associations with drunken horse grass (Achnatherum inebrians), providing biotic and abiotic stress protection to its host. However, it is unclear how E. gansuensis affects the assembly of host plant-associated bacterial communities after ammonium nitrogen (NH4+-N) treatment. We examined the shoot- and root-associated bacterial microbiota and root metabolites of A. inebrians when infected (I) or uninfected (F) with E. gansuensis endophyte. The results showed more pronounced NH4+-N-induced microbial and metabolic changes in the endophyte-infected plants compared to the endophyte-free plants. E. gansuensis significantly altered bacterial community composition and β-diversity in shoots and roots and increased bacterial α-diversity under NH4+-N treatment. The relative abundance of 117 and 157 root metabolites significantly changed with E. gansuensis infection under water and NH4+-N treatment compared to endophyte-free plants. Root bacterial community composition was significantly related to the abundance of the top 30 metabolites [variable importance in the projection (VIP) > 2 and VIP > 3] contributing to differences between I and F plants, especially alkaloids. The correlation network between root microbiome and metabolites was complex. Microorganisms in the Proteobacteria and Firmicutes phyla were significantly associated with the R00693 metabolic reaction of cysteine and methionine metabolism. Co-metabolism network analysis revealed common metabolites between host plants and microorganisms.IMPORTANCEOur results suggest that the effect of endophyte infection is sensitive to nitrogen availability. Endophyte symbiosis altered the composition of shoot and root bacterial communities, increasing bacterial diversity. There was also a change in the class and relative abundance of metabolites. We found a complex co-occurrence network between root microorganisms and metabolites, with some metabolites shared between the host plant and its microbiome. The precise ecological function of the metabolites produced in response to endophyte infection remains unknown. However, some of these compounds may facilitate plant-microbe symbiosis by increasing the uptake of beneficial soil bacteria into plant tissues. Overall, these findings advance our understanding of the interactions between the microbiome, metabolome, and endophyte symbiosis in grasses. The results provide critical insight into the mechanisms by which the plant microbiome responds to nutrient stress in the presence of fungal endophytes.
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Affiliation(s)
- Yuanyuan Jin
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, Lanzhou University, Lanzhou, China
- Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Lanzhou University, Lanzhou, China
- Engineering Research Center of Grassland Industry, Ministry of Education, Lanzhou University, Lanzhou, China
- Gansu Tech Innovation Center of Western China Grassland Industry, Lanzhou University, Lanzhou, China
- Center for Grassland Microbiome, Lanzhou University, Lanzhou, China
- College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
| | - Zhenjiang Chen
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, Lanzhou University, Lanzhou, China
- Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Lanzhou University, Lanzhou, China
- Engineering Research Center of Grassland Industry, Ministry of Education, Lanzhou University, Lanzhou, China
- Gansu Tech Innovation Center of Western China Grassland Industry, Lanzhou University, Lanzhou, China
- Center for Grassland Microbiome, Lanzhou University, Lanzhou, China
- College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
| | - James F. White
- Department of Plant Biology, Rutgers University, New Brunswick, New Jersey, USA
| | - Kamran Malik
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, Lanzhou University, Lanzhou, China
- Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Lanzhou University, Lanzhou, China
- Engineering Research Center of Grassland Industry, Ministry of Education, Lanzhou University, Lanzhou, China
- Gansu Tech Innovation Center of Western China Grassland Industry, Lanzhou University, Lanzhou, China
- Center for Grassland Microbiome, Lanzhou University, Lanzhou, China
- College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
| | - Chunjie Li
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, Lanzhou University, Lanzhou, China
- Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Lanzhou University, Lanzhou, China
- Engineering Research Center of Grassland Industry, Ministry of Education, Lanzhou University, Lanzhou, China
- Gansu Tech Innovation Center of Western China Grassland Industry, Lanzhou University, Lanzhou, China
- Center for Grassland Microbiome, Lanzhou University, Lanzhou, China
- College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
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Liu J, Xu Y, Si YJ, Li BQ, Chen P, Wu LL, Guo P, Ji RQ. The Diverse Mycorrizal Morphology of Rhododendron dauricum, the Fungal Communities Structure and Dynamics from the Mycorrhizosphere. J Fungi (Basel) 2024; 10:65. [PMID: 38248974 PMCID: PMC10817234 DOI: 10.3390/jof10010065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 01/10/2024] [Accepted: 01/11/2024] [Indexed: 01/23/2024] Open
Abstract
It is generally believed that mycorrhiza is a microecosystem composed of mycorrhizal fungi, host plants and other microscopic organisms. The mycorrhiza of Rhododendron dauricum is more complex and the diverse morphology of our investigated results displays both typical ericoid mycorrhizal characteristics and ectomycorrhizal traits. The characteristics of ectendoomycorrhiza, where mycelial invade from the outside into the root cells, have also been observed. In order to further clarify the mycorrhizal fungi members and other fungal communities of R. dauricum mycorrhiza, and explore the effects of vegetation and soil biological factors on their community structure, we selected two woodlands in the northeast of China as samples-one is a mixed forest of R. dauricum and Quercus mongolica, and the other a mixed forest of R. dauricum, Q. mongolica, and Pinus densiflor. The sampling time was during the local growing season, from June to September. High-throughput sequencing yielded a total of 3020 fungal amplicon sequence variants (ASVs), which were based on sequencing of the internal transcribed spacer ribosomal RNA (ITS rRNA) via the Illumina NovaSeq platform. In the different habitats of R. dauricum, there are differences in the diversity of fungi obtained from mycorrhizal niches, and specifically the mycorrhizal fungal community structure in the complex vegetation of mixed forests, where R. dauricum is found, exhibits greater stability, with relatively minor changes over time. Soil fungi are identified as the primary source of fungi within the mycorrhizal niche, and the abundance of mycorrhizal fungi from mycorrhizal niches in R. dauricum is significantly influenced by soil pH, organic matter, and available nitrogen. The relationship between soil fungi and mycorrhizal fungi from mycorrhizal niches is simultaneously found to be intricate, while the genus Hydnellum emerges as a central genus among mycorrhizal fungi from mycorrhizal niches. However, there is currently a substantial gap in the foundational research of this genus, including the fact that mycorrhizal fungi from mycorrhizal niches have, compared to fungi present in the soil, proven to be more sensitive to changes in soil moisture.
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Affiliation(s)
| | | | | | | | | | | | | | - Rui-Qing Ji
- Engineering Research Center of Edible and Medicinal Fungi, Ministry of Education, Jilin Agricultural University, Changchun 130118, China; (J.L.); (Y.X.); (Y.-J.S.); (B.-Q.L.); (P.C.); (L.-L.W.); (P.G.)
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Mutanwad KV, Debreczeny M, Lucyshyn D. Root Hair Imaging Using Confocal Microscopy. Methods Mol Biol 2024; 2787:81-94. [PMID: 38656483 DOI: 10.1007/978-1-0716-3778-4_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Plant genetics plays a key role in determining root hair initiation and development. A complex network of genetic interactions therefore closely monitors and influences root hair phenotype and morphology. The significance of these genes can be studied by employing, for instance, loss-of-function mutants, overexpression plant lines, and fluorescently labeled constructs. Confocal laser scanning microscopy is a great tool to visually observe and document these morphological features. This chapter elaborates the techniques involved in handling of microscopic setup to acquire images displaying root hair distribution along the fully elongated zone of Arabidopsis thaliana roots. Additionally, we illustrate an approach to visualize early fate determination of epidermal cells in the root apical meristem, by describing a method for imaging YFP tagged transgenic plant lines.
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Affiliation(s)
- Krishna Vasant Mutanwad
- Institute of Molecular Plant Biology, Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Monika Debreczeny
- Core Facility Multiscale Imaging, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Doris Lucyshyn
- Institute of Molecular Plant Biology, Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria.
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Mukherjee S, Corpas FJ. H 2 O 2 , NO, and H 2 S networks during root development and signalling under physiological and challenging environments: Beneficial or toxic? PLANT, CELL & ENVIRONMENT 2023; 46:688-717. [PMID: 36583401 PMCID: PMC10108057 DOI: 10.1111/pce.14531] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 12/25/2022] [Accepted: 12/27/2022] [Indexed: 05/27/2023]
Abstract
Hydrogen peroxide (H2 O2 ) is a reactive oxygen species (ROS) and a key modulator of the development and architecture of the root system under physiological and adverse environmental conditions. Nitric oxide (NO) and hydrogen sulphide (H2 S) also exert myriad functions on plant development and signalling. Accumulating pieces of evidence show that depending upon the dose and mode of applications, NO and H2 S can have synergistic or antagonistic actions in mediating H2 O2 signalling during root development. Thus, H2 O2 -NO-H2 S crosstalk might essentially impart tolerance to elude oxidative stress in roots. Growth and proliferation of root apex involve crucial orchestration of NO and H2 S-mediated ROS signalling which also comprise other components including mitogen-activated protein kinase, cyclins, cyclin-dependent kinases, respiratory burst oxidase homolog (RBOH), and Ca2+ flux. This assessment provides a comprehensive update on the cooperative roles of NO and H2 S in modulating H2 O2 homoeostasis during root development, abiotic stress tolerance, and root-microbe interaction. Furthermore, it also analyses the scopes of some fascinating future investigations associated with strigolactone and karrikins concerning H2 O2 -NO-H2 S crosstalk in plant roots.
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Affiliation(s)
- Soumya Mukherjee
- Department of Botany, Jangipur CollegeUniversity of KalyaniWest BengalIndia
| | - Francisco J. Corpas
- Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Stress, Development and Signalling in PlantsEstación Experimental del Zaidín (Spanish National Research Council, CSIC)GranadaSpain
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Aparicio MA, Lucena C, García MJ, Ruiz-Castilla FJ, Jiménez-Adrián P, López-Berges MS, Prieto P, Alcántara E, Pérez-Vicente R, Ramos J, Romera FJ. The nonpathogenic strain of Fusarium oxysporum FO12 induces Fe deficiency responses in cucumber (Cucumis sativus L.) plants. PLANTA 2023; 257:50. [PMID: 36757472 PMCID: PMC9911487 DOI: 10.1007/s00425-023-04079-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 01/18/2023] [Indexed: 05/16/2023]
Abstract
MAIN CONCLUSION FO12 strain enhances Fe deficiency responses in cucumber plants, probably through the production of ethylene and NO in the subapical regions of the roots. Rhizosphere microorganisms can elicit induced systemic resistance (ISR) in plants. This type of resistance involves complex mechanisms that confer protection to the plant against pathogen attack. Additionally, it has been reported by several studies that ISR and Fe deficiency responses are modulated by common pathways, involving some phytohormones and signaling molecules, like ethylene and nitric oxide (NO). The aim of this study was to determine whether the nonpathogenic strain of Fusarium oxysporum FO12 can induce Fe deficiency responses in cucumber (Cucumis sativus L.) plants. Our results demonstrate that the root inoculation of cucumber plants with the FO12 strain promotes plant growth after several days of cultivation, as well as rhizosphere acidification and enhancement of ferric reductase activity. Moreover, Fe-related genes, such as FRO1, IRT1 and HA1, are upregulated at certain times after FO12 inoculation either upon Fe-deficiency or Fe-sufficient conditions. Furthermore, it has been found that this fungus colonizes root cortical tissues, promoting the upregulation of ethylene synthesis genes and NO production in the root subapical regions. To better understand the effects of the FO12 strain on field conditions, cucumber plants were inoculated and cultivated in a calcareous soil under greenhouse conditions. The results obtained show a modification of some physiological parameters in the inoculated plants, such as flowering and reduction of tissue necrosis. Overall, the results suggest that the FO12 strain could have a great potential as a Fe biofertilizer and biostimulant.
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Affiliation(s)
- Miguel A Aparicio
- Departamento de Química Agrícola, Edafología y Microbiología, Edificio Severo Ochoa (C-6), Campus de Excelencia Internacional Agroalimentario de Rabanales (ceiA3), University of Córdoba, 14014, Córdoba, Spain
| | - Carlos Lucena
- Departamento de Agronomía, Edificio Celestino Mutis (C-4), Campus de Excelencia Internacional Agroalimentario de Rabanales (ceiA3), University of Córdoba, 14014, Córdoba, Spain.
| | - María J García
- Departamento de Agronomía, Edificio Celestino Mutis (C-4), Campus de Excelencia Internacional Agroalimentario de Rabanales (ceiA3), University of Córdoba, 14014, Córdoba, Spain
| | - Francisco J Ruiz-Castilla
- Departamento de Química Agrícola, Edafología y Microbiología, Edificio Severo Ochoa (C-6), Campus de Excelencia Internacional Agroalimentario de Rabanales (ceiA3), University of Córdoba, 14014, Córdoba, Spain
| | - Pablo Jiménez-Adrián
- Departamento de Química Agrícola, Edafología y Microbiología, Edificio Severo Ochoa (C-6), Campus de Excelencia Internacional Agroalimentario de Rabanales (ceiA3), University of Córdoba, 14014, Córdoba, Spain
| | - Manuel S López-Berges
- Departamento de Genética, Edificio Gregor Mendel (C-5), Campus de Excelencia Internacional Agroalimentario de Rabanales (ceiA3), University of Córdoba, 14014, Córdoba, Spain
| | - Pilar Prieto
- Departamento de Mejora Genética, Instituto de Agricultura Sostenible (IAS), Consejo Superior de Investigaciones Científicas (CSIC), 14004, Córdoba, Spain
| | - Esteban Alcántara
- Departamento de Agronomía, Edificio Celestino Mutis (C-4), Campus de Excelencia Internacional Agroalimentario de Rabanales (ceiA3), University of Córdoba, 14014, Córdoba, Spain
| | - Rafael Pérez-Vicente
- Departamento de Botánica, Ecología y Fisiología Vegetal, Edificio Celestino Mutis (C-4), Campus de Excelencia Internacional Agroalimentario de Rabanales (ceiA3), University of Córdoba, 14014, Córdoba, Spain
| | - José Ramos
- Departamento de Química Agrícola, Edafología y Microbiología, Edificio Severo Ochoa (C-6), Campus de Excelencia Internacional Agroalimentario de Rabanales (ceiA3), University of Córdoba, 14014, Córdoba, Spain
| | - Francisco J Romera
- Departamento de Agronomía, Edificio Celestino Mutis (C-4), Campus de Excelencia Internacional Agroalimentario de Rabanales (ceiA3), University of Córdoba, 14014, Córdoba, Spain
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Chiaranunt P, White JF. Plant Beneficial Bacteria and Their Potential Applications in Vertical Farming Systems. PLANTS (BASEL, SWITZERLAND) 2023; 12:400. [PMID: 36679113 PMCID: PMC9861093 DOI: 10.3390/plants12020400] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/12/2023] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
In this literature review, we discuss the various functions of beneficial plant bacteria in improving plant nutrition, the defense against biotic and abiotic stress, and hormonal regulation. We also review the recent research on rhizophagy, a nutrient scavenging mechanism in which bacteria enter and exit root cells on a cyclical basis. These concepts are covered in the contexts of soil agriculture and controlled environment agriculture, and they are also used in vertical farming systems. Vertical farming-its advantages and disadvantages over soil agriculture, and the various climatic factors in controlled environment agriculture-is also discussed in relation to plant-bacterial relationships. The different factors under grower control, such as choice of substrate, oxygenation rates, temperature, light, and CO2 supplementation, may influence plant-bacterial interactions in unintended ways. Understanding the specific effects of these environmental factors may inform the best cultural practices and further elucidate the mechanisms by which beneficial bacteria promote plant growth.
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Yang M, Qi Y, Liu J, Wu Z, Gao P, Chen Z, Huang F, Yu L. Dynamic changes in the endophytic bacterial community during maturation of Amorphophallus muelleri seeds. Front Microbiol 2022; 13:996854. [PMID: 36225382 PMCID: PMC9549114 DOI: 10.3389/fmicb.2022.996854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 09/08/2022] [Indexed: 11/17/2022] Open
Abstract
The seed microbiota is considered to be the starting point of the accumulation of plant microbiota, which is conducive to the preservation and germination of seeds and the establishment and development of seedlings. Our understanding of the colonization and migration dynamics of microbial taxa during seed development and maturation is still limited. This study used 16S rRNA high-throughput sequencing to investigate the dynamic changes in the composition and diversity of the endophytic bacterial community during maturation of Amorphophallus muelleri seeds. The results showed that as seeds matured (green to red), the Shannon index of their endophytic bacterial community first decreased and then increased, and the ACE and Chao1 indices of the endophytic bacterial community decreased gradually. The Shannon, ACE, and Chao1 indices of the endophytic bacterial community in the seed coat first decreased and then increased. Principal coordinate analysis of the bacterial communities revealed that the seed coat at different maturity stages showed significantly distinct bacterial communities and formed different clusters according to maturity stage. The bacterial communities of green and red seeds showed a clear separation, but they both overlapped with those of yellow seeds, indicating that some core taxa were present throughout seed maturation, but their relative abundance was dynamically changing. As the seeds grew more mature, the relative abundance of some bacterial communities with plant growth-promoting traits and others correlated with plant resistance (e.g., Burkholderia-Caballeronia-Paraburkholderia, Bacillus, Pseudomonas, Bradyrhizobium, Streptomyces) tended to increase and peaked in fully mature seeds and seed coats. The endophytic bacterial community of A. muelleri seeds seems to be driven by the seed maturation state, which can provide a theoretical basis for a comprehensive understanding of the assembly process of the microbial community during A. muelleri seed maturation.
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Affiliation(s)
- Min Yang
- Yunnan Urban Agricultural Engineering and Technological Research Center, College of Agronomy, Kunming University, Kunming, China
- College of Plant Protection, Yunnan Agricultural University, Kunming, China
| | - Ying Qi
- Yunnan Urban Agricultural Engineering and Technological Research Center, College of Agronomy, Kunming University, Kunming, China
| | - Jiani Liu
- Yunnan Urban Agricultural Engineering and Technological Research Center, College of Agronomy, Kunming University, Kunming, China
| | - Zhixing Wu
- Yunnan Urban Agricultural Engineering and Technological Research Center, College of Agronomy, Kunming University, Kunming, China
| | - Penghua Gao
- Yunnan Urban Agricultural Engineering and Technological Research Center, College of Agronomy, Kunming University, Kunming, China
| | - Zebin Chen
- Yunnan Urban Agricultural Engineering and Technological Research Center, College of Agronomy, Kunming University, Kunming, China
| | - Feiyan Huang
- Yunnan Urban Agricultural Engineering and Technological Research Center, College of Agronomy, Kunming University, Kunming, China
- *Correspondence: Feiyan Huang,
| | - Lei Yu
- Yunnan Urban Agricultural Engineering and Technological Research Center, College of Agronomy, Kunming University, Kunming, China
- Lei Yu,
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Sharma VK, Parmar S, Tang W, Hu H, White JF, Li H. Effects of fungal seed endophyte FXZ2 on Dysphania ambrosioides Zn/Cd tolerance and accumulation. Front Microbiol 2022; 13:995830. [PMID: 36212824 PMCID: PMC9532605 DOI: 10.3389/fmicb.2022.995830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022] Open
Abstract
Metal-induced oxidative stress in contaminated soils affects plant growth. In the present study, we evaluated the role of seed endophyte FXZ2 on Dysphania ambrosioides Zn/Cd tolerance and accumulation. A series of pot experiments were conducted under variable Zn (500, 1,000, and 1,500 mg kg–1) and Cd (5, 15, 30, and 60 mg kg–1). The results demonstrated that FXZ2-inoculation significantly enhanced the growth of D. ambrosioides and improved its chlorophyll and GSH content. In the rhizosphere, FXZ2 inoculation changed the chemical speciation of Zn/Cd and thus affected their uptake and accumulation in host plants. The exchangeable and carbonate-bound fractions (F1 + F2) of Zn decreased in the rhizosphere of FXZ2-inoculated plants (E+) as compared to non-inoculated plants (E-) under Zn stress (500 and 1,000 mg kg–1), correspondingly, Zn in the shoots of E+ decreased (p < 0.05). However, at Cd stress (30 and 60 mg kg–1), the F1 + F2 fractions of Cd in E+ rhizospheric soils increased; subsequently, Cd in the shoots of E+ increased (p < 0.05). FXZ2 could exogenously secrete phytohormones IAA, GA, and JA. The study suggests that seed endophyte FXZ2 can increase Zn/Cd tolerance of host plant by altering Zn/Cd speciation in rhizospheric soils, as well as exogenous production of phytohormones to promote growth, lowering oxidative damage while enhancing antioxidant properties. For Zn/Cd accumulation, it has opposite effects: Zn uptake in E+ plants was significantly (p < 0.05) decreased, while Cd accumulation in E+ plants was significantly (p < 0.05) increased. Thus, FXZ2 has excellent application prospects in Cd phytoextraction and decreasing Zn toxicity in agriculturally important crops.
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Affiliation(s)
- Vijay K. Sharma
- Medical School, Kunming University of Science and Technology, Kunming, China
| | - Shobhika Parmar
- Medical School, Kunming University of Science and Technology, Kunming, China
| | - Wenting Tang
- Medical School, Kunming University of Science and Technology, Kunming, China
| | - Haiyan Hu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China
| | - James F. White
- Department of Plant Biology, Rutgers University, New Brunswick, NJ, United States
| | - Haiyan Li
- Medical School, Kunming University of Science and Technology, Kunming, China
- *Correspondence: Haiyan Li,
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9
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Verma SK, Chen Q, White JF. Evaluation of colonization and mutualistic endophytic symbiosis of Escherichia coli with tomato and Bermuda grass seedlings. PeerJ 2022; 10:e13879. [PMID: 35971430 PMCID: PMC9375544 DOI: 10.7717/peerj.13879] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 07/19/2022] [Indexed: 01/18/2023] Open
Abstract
Escherichia coli is generally considered a bacterium associated with animal microbiomes. However, we present evidence that E. coli may also mutualistically colonize roots of plant species, even to the extent that it may become endophytic in plants. In this study we used GFP tagged E. coli to observe its colonization and effects on tomato (Solanum lycopersicum) and Bermuda grass (Cynodon dactylon) seedling development and growth. Inoculation with the bacterium significantly improved root development of both seedlings tested. Treatment also increased the photosynthetic pigments in Bermuda grass seedlings. However, effects on shoot length in both seedlings were not significant. This bacterium was found to produce indole acetic acid (IAA) up to 8.68 ± 0.43 µg ml-1 in the broth medium amended with tryptophan. Effects on seedling root growth could, in part, be explained by IAA production. Bacteria successfully colonized the root surfaces and interiors of both seedlings. Tagged bacteria expressing the GFP were observed in the vascular tissues of Bermuda grass seedling roots. Seedlings with bacteria showed greater survival and were healthier than seedlings without bacteria, indicating that E. coli set up a successful mutualistic symbiosis with seedlings. E. coli is not commonly considered to be a plant endophyte but is more generally considered to be a crop contaminant. In this study we show that E. coli may also be an endophyte in plant tissues.
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Affiliation(s)
- Satish K. Verma
- Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Qiang Chen
- Department of Plant Biology, Rutgers University, New Brunswick, New Jersey, United States of America
| | - James Francis White
- Department of Plant Biology, Rutgers University, New Brunswick, New Jersey, United States of America
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10
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Micci A, Zhang Q, Chang X, Kingsley K, Park L, Chiaranunt P, Strickland R, Velazquez F, Lindert S, Elmore M, Vines PL, Crane S, Irizarry I, Kowalski KP, Johnston-Monje D, White JF. Histochemical Evidence for Nitrogen-Transfer Endosymbiosis in Non-Photosynthetic Cells of Leaves and Inflorescence Bracts of Angiosperms. BIOLOGY 2022; 11:biology11060876. [PMID: 35741397 PMCID: PMC9220352 DOI: 10.3390/biology11060876] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 05/15/2022] [Accepted: 06/01/2022] [Indexed: 12/13/2022]
Abstract
Simple Summary We used light and confocal microscopy to visualize bacteria in leaf and bract cells of more than 30 species in 18 families of seed plants. We detected chemical exchanges between intracellular bacteria and plant cells. We found that endophytic bacteria that show evidence of the transfer of nitrogen to plants are present in non-photosynthetic cells of leaves and bracts of diverse plant species. Nitrogen transfer from bacteria was observed in epidermal cells, various filamentous and glandular trichomes, and other non-photosynthetic cells. The most efficient of the nitrogen-transfer endosymbioses were seen to involve glandular trichomes, as seen in hops (Humulus lupulus) and hemp (Cannabis sativa). Trichome chemistry is hypothesized to function to scavenge oxygen around bacteria to facilitate nitrogen fixation. Abstract We used light and confocal microscopy to visualize bacteria in leaf and bract cells of more than 30 species in 18 families of seed plants. Through histochemical analysis, we detected hormones (including ethylene and nitric oxide), superoxide, and nitrogenous chemicals (including nitric oxide and nitrate) around bacteria within plant cells. Bacteria were observed in epidermal cells, various filamentous and glandular trichomes, and other non-photosynthetic cells. Most notably, bacteria showing nitrate formation based on histochemical staining were present in glandular trichomes of some dicots (e.g., Humulus lupulus and Cannabis sativa). Glandular trichome chemistry is hypothesized to function to scavenge oxygen around bacteria and reduce oxidative damage to intracellular bacterial cells. Experiments to assess the differential absorption of isotopic nitrogen into plants suggest the assimilation of nitrogen into actively growing tissues of plants, where bacteria are most active and carbohydrates are more available. The leaf and bract cell endosymbiosis types outlined in this paper have not been previously reported and may be important in facilitating plant growth, development, oxidative stress resistance, and nutrient absorption into plants. It is unknown whether leaf and bract cell endosymbioses are significant in increasing the nitrogen content of plants. From the experiments that we conducted, it is impossible to know whether plant trichomes evolved specifically as organs for nitrogen fixation or if, instead, trichomes are structures in which bacteria easily colonize and where some casual nitrogen transfer may occur between bacteria and plant cells. It is likely that the endosymbioses seen in leaves and bracts are less efficient than those of root nodules of legumes in similar plants. However, the presence of endosymbioses that yield nitrate in plants could confer a reduced need for soil nitrogen and constitute increased nitrogen-use efficiency, even if the actual amount of nitrogen transferred to plant cells is small. More research is needed to evaluate the importance of nitrogen transfer within leaf and bract cells of plants.
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Affiliation(s)
- April Micci
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA; (Q.Z.); (X.C.); (K.K.); (L.P.); (P.C.); (R.S.); (F.V.); (S.L.); (M.E.); (P.L.V.)
- Correspondence: (A.M.); (J.F.W.); Tel.: +848-932-6286 (J.F.W.)
| | - Qiuwei Zhang
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA; (Q.Z.); (X.C.); (K.K.); (L.P.); (P.C.); (R.S.); (F.V.); (S.L.); (M.E.); (P.L.V.)
| | - Xiaoqian Chang
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA; (Q.Z.); (X.C.); (K.K.); (L.P.); (P.C.); (R.S.); (F.V.); (S.L.); (M.E.); (P.L.V.)
| | - Kathryn Kingsley
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA; (Q.Z.); (X.C.); (K.K.); (L.P.); (P.C.); (R.S.); (F.V.); (S.L.); (M.E.); (P.L.V.)
| | - Linsey Park
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA; (Q.Z.); (X.C.); (K.K.); (L.P.); (P.C.); (R.S.); (F.V.); (S.L.); (M.E.); (P.L.V.)
| | - Peerapol Chiaranunt
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA; (Q.Z.); (X.C.); (K.K.); (L.P.); (P.C.); (R.S.); (F.V.); (S.L.); (M.E.); (P.L.V.)
| | - Raquele Strickland
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA; (Q.Z.); (X.C.); (K.K.); (L.P.); (P.C.); (R.S.); (F.V.); (S.L.); (M.E.); (P.L.V.)
| | - Fernando Velazquez
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA; (Q.Z.); (X.C.); (K.K.); (L.P.); (P.C.); (R.S.); (F.V.); (S.L.); (M.E.); (P.L.V.)
| | - Sean Lindert
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA; (Q.Z.); (X.C.); (K.K.); (L.P.); (P.C.); (R.S.); (F.V.); (S.L.); (M.E.); (P.L.V.)
| | - Matthew Elmore
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA; (Q.Z.); (X.C.); (K.K.); (L.P.); (P.C.); (R.S.); (F.V.); (S.L.); (M.E.); (P.L.V.)
| | - Philip L. Vines
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA; (Q.Z.); (X.C.); (K.K.); (L.P.); (P.C.); (R.S.); (F.V.); (S.L.); (M.E.); (P.L.V.)
| | - Sharron Crane
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ 08901, USA;
| | - Ivelisse Irizarry
- School of Health and Sciences, Universidad del Sagrado Corazón, San Juan 00914, Puerto Rico;
| | - Kurt P. Kowalski
- US Geological Survey Great Lakes Science Center, Ann Arbor, MI 48105, USA;
| | - David Johnston-Monje
- Max Planck Tandem Group in Plant Microbial Ecology, Universidad del Valle, Cali 760043, Colombia;
| | - James F. White
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA; (Q.Z.); (X.C.); (K.K.); (L.P.); (P.C.); (R.S.); (F.V.); (S.L.); (M.E.); (P.L.V.)
- Correspondence: (A.M.); (J.F.W.); Tel.: +848-932-6286 (J.F.W.)
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11
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Kumar K, Verma A, Pal G, Anubha, White JF, Verma SK. Seed Endophytic Bacteria of Pearl Millet ( Pennisetum glaucum L.) Promote Seedling Development and Defend Against a Fungal Phytopathogen. Front Microbiol 2021; 12:774293. [PMID: 34956137 PMCID: PMC8696672 DOI: 10.3389/fmicb.2021.774293] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Accepted: 11/08/2021] [Indexed: 12/02/2022] Open
Abstract
Seed endophytic bacteria (SEB) are primary symbionts that play crucial roles in plant growth and development. The present study reports the isolation of seven culturable SEB including Kosakonia cowanii (KAS1), Bacillus subtilis (KAS2), Bacillus tequilensis (KAS3), Pantoea stewartii (KAS4), Paenibacillus dendritiformis (KAS5), Pseudomonas aeruginosa (KAS6), and Bacillus velezensis (KAS7) in pearl millet seeds. All the isolates were characterized for their plant growth promoting activities. Most of the SEB also inhibited the growth of tested fungal phytopathogens in dual plate culture. Removal of these SEB from seeds compromised the growth and development of seedlings, however, re-inoculation with the SEB (Kosakonia cowanii, Pantoea stewartii, and Pseudomonas aeruginosa) restored the growth and development of seedlings significantly. Fluorescence microscopy showed inter and intracellular colonization of SEB in root parenchyma and root hair cells. Lipopeptides were extracted from all three Bacillus spp. which showed strong antifungal activity against tested fungal pathogens. Antifungal lipopeptide genes were also screened in Bacillus spp. After lipopeptide treatment, live-dead staining with fluorescence microscopy along with bright-field and scanning electron microscopy (SEM) revealed structural deformation and cell death in Fusarium mycelia and spores. Furthermore, the development of pores in the membrane and leakages of protoplasmic substances from cells and ultimately death of hyphae and spores were also confirmed. In microcosm assays, treatment of seeds with Bacillus subtilis or application of its lipopeptide alone significantly protected seedlings from Fusarium sp. infection.
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Affiliation(s)
- Kanchan Kumar
- Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Anand Verma
- Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Gaurav Pal
- Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Anubha
- Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, India
| | - James F White
- Department of Plant Biology, Rutgers University, New Brunswick, NJ, United States
| | - Satish K Verma
- Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, India
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12
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González-Benítez N, Martín-Rodríguez I, Cuesta I, Arrayás M, White JF, Molina MC. Endophytic Microbes Are Tools to Increase Tolerance in Jasione Plants Against Arsenic Stress. Front Microbiol 2021; 12:664271. [PMID: 34690941 PMCID: PMC8527096 DOI: 10.3389/fmicb.2021.664271] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 06/08/2021] [Indexed: 01/04/2023] Open
Abstract
Seed microbiota is becoming an emergent area of research. Host plant microbial diversity is increasingly well described, yet relatively little is known about the stressors driving plant endomicrobiota at the metaorganism level. The present work examines the role of horizontal and vertical transmission of bacterial microbiota in response to abiotic stress generated by arsenic. Horizontal transmission is achieved by bioaugmentation with the endophyte Rhodococcus rhodochrous, while vertical transmission comes via maternal inheritance from seeds. To achieve this goal, all experiments were conducted with two Jasione species. J. montana is tolerant to arsenic (As), whereas J. sessiliflora, being phylogenetically close to J. montana, was not previously described as As tolerant. The Jasione core bacterial endophytes are composed of genera Pseudomonas, Ralstonia, Undibacterium, Cutibacterium, and Kocuria and family Comamanadaceae across different environmental conditions. All these operational taxonomic units (OTUs) coexisted from seeds to the development of the seedling, independently of As stress, or bioaugmentation treatment and Jasione species. R. rhodochrous colonized efficiently both species, driving the endomicrobiota structure of Jasione with a stronger effect than As stress. Despite the fact that most of the OTUs identified inside Jasione seeds and seedlings belonged to rare microbiota, they represent a large bacterial reservoir offering important physiological and ecological traits to the host. Jasione traits co-regulated with R. rhodochrous, and the associated microbiota improved the host response to As stress. NGS-Illumina tools provided further knowledge about the ecological and functional roles of plant endophytes.
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Affiliation(s)
- Natalia González-Benítez
- Department of Biology, Geology, Physics, and Inorganic Chemistry, Universidad Rey Juan Carlos, Madrid, Spain
| | - Irene Martín-Rodríguez
- Department of Biology, Geology, Physics, and Inorganic Chemistry, Universidad Rey Juan Carlos, Madrid, Spain
| | - Isabel Cuesta
- Unidad de Bioinformática, Instituto de Salud Carlos III, Madrid, Spain
| | - Manuel Arrayás
- Área de Electromagnetismo, Universidad Rey Juan Carlos, Madrid, Spain
| | - James Francis White
- Department of Plant Biology, Rutgers University, New Brunswick, NJ, United States
| | - María Carmen Molina
- Department of Biology, Geology, Physics, and Inorganic Chemistry, Universidad Rey Juan Carlos, Madrid, Spain.,Department of Plant Biology, Rutgers University, New Brunswick, NJ, United States
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13
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Bioprospecting Desert Plants for Endophytic and Biostimulant Microbes: A Strategy for Enhancing Agricultural Production in a Hotter, Drier Future. BIOLOGY 2021; 10:biology10100961. [PMID: 34681060 PMCID: PMC8533330 DOI: 10.3390/biology10100961] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 09/18/2021] [Accepted: 09/21/2021] [Indexed: 01/14/2023]
Abstract
Simple Summary Endophytes are microbes that live inside plants without causing negative effects in their hosts. All land plants are known to have endophytes, and these endophytes have the capacity to be transferred between plants. Taking endophytes from desert plants, which grow in low-nutrient, high-stress environments, and transferring them to crop plants may alleviate some of the challenges being faced by the agricultural industry, such as increasing drought frequency and rising opposition to chemical use in agriculture. Studies have shown that desert endophytes have the capacity to increase nutrient uptake and increase plant resistance to drought and heat stress, salt stress, and pathogen attack. Currently, the agricultural industry focuses on using irrigation, chemical fertilizers, and chemical pesticides to solve such issues, which can be extremely damaging to the environment. While there is still a lot that is unknown about endophytes, particularly desert plant endophytes, current research provides evidence that desert plant endophytes could be an environmentally friendly alternative to the conventional solutions being applied today. Abstract Deserts are challenging places for plants to survive in due to low nutrient availability, drought and heat stress, water stress, and herbivory. Endophytes—microbes that colonize and infect plant tissues without causing apparent disease—may contribute to plant success in such harsh environments. Current knowledge of desert plant endophytes is limited, but studies performed so far reveal that they can improve host nutrient acquisition, increase host tolerance to abiotic stresses, and increase host resistance to biotic stresses. When considered in combination with their broad host range and high colonization rate, there is great potential for desert endophytes to be used in a commercial agricultural setting, especially as croplands face more frequent and severe droughts due to climate change and as the agricultural industry faces mounting pressure to break away from agrochemicals towards more environmentally friendly alternatives. Much is still unknown about desert endophytes, but future studies may prove fruitful for the discovery of new endophyte-based biofertilizers, biocontrol agents, and abiotic stress relievers of crops.
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14
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Beltran-Garcia MJ, White JF. Introduction to Special Issue: Plant Microbiome Augmentation and Stimulation-New Strategies to Grow Crops with Reduced Agrochemicals. Microorganisms 2021; 9:1887. [PMID: 34576782 PMCID: PMC8471635 DOI: 10.3390/microorganisms9091887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 09/03/2021] [Indexed: 11/24/2022] Open
Abstract
Since the early work of Justus von Liebig on nutrient absorption in plants in the 1800s [...].
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Affiliation(s)
- Miguel J. Beltran-Garcia
- Lab 309-E Building, Chemistry Department, Universidad Autonoma de Guadalajara, Zapopan 45129, Jalisco, Mexico
- Departamento de Biotecnologicas y Ambientales, Universidad Autonoma de Guadalajara, Zapopan 45129, Jalisco, Mexico
| | - James F. White
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA
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15
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The Potential Application of Endophytes in Management of Stress from Drought and Salinity in Crop Plants. Microorganisms 2021; 9:microorganisms9081729. [PMID: 34442808 PMCID: PMC8398416 DOI: 10.3390/microorganisms9081729] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/10/2021] [Accepted: 08/12/2021] [Indexed: 01/05/2023] Open
Abstract
Endophytic microorganisms present inside the host plant play an essential role in host fitness, nutrient supply and stress tolerance. Endophytes are often used in sustainable agriculture as biofertilizers, biopesticides and as inoculants to mitigate abiotic stresses including salinity, drought, cold and pH variation in the soil. In changing climatic conditions, abiotic stresses create global challenges to achieve optimum crop yields in agricultural production. Plants experience stress conditions that involve endogenous boosting of their immune system or the overexpression of their defensive redox regulatory systems with increased reactive oxygen species (ROS). However, rising stress factors overwhelm the natural redox protection systems of plants, which leads to massive internal oxidative damage and death. Endophytes are an integral internal partner of hosts and have been shown to mitigate abiotic stresses via modulating local or systemic mechanisms and producing antioxidants to counteract ROS in plants. Advancements in omics and other technologies have been made, but potential application of endophytes remains largely unrealized. In this review article, we will discuss the diversity, population and interaction of endophytes with crop plants as well as potential applications in abiotic stress management.
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16
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Evaluation of Indigenous Olive Biocontrol Rhizobacteria as Protectants against Drought and Salt Stress. Microorganisms 2021; 9:microorganisms9061209. [PMID: 34204989 PMCID: PMC8230297 DOI: 10.3390/microorganisms9061209] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 05/27/2021] [Accepted: 06/01/2021] [Indexed: 11/24/2022] Open
Abstract
Stress caused by drought and salinity may compromise growth and productivity of olive (Olea europaea L.) tree crops. Several studies have reported the use of beneficial rhizobacteria to alleviate symptoms produced by these stresses, which is attributed in some cases to the activity of 1-aminocyclopropane-1-carboxylic acid deaminase (ACD). A collection of beneficial olive rhizobacteria was in vitro screened for ACD activity. Pseudomonas sp. PICF6 displayed this phenotype and sequencing of its genome confirmed the presence of an acdS gene. In contrast, the well-known root endophyte and biocontrol agent Pseudomonas simiae PICF7 was defective in ACD activity, even though the presence of an ACD-coding gene was earlier predicted in its genome. In this study, an unidentified deaminase was confirmed instead. Greenhouse experiments with olive ‘Picual’ plants inoculated either with PICF6 or PICF7, or co-inoculated with both strains, and subjected to drought or salt stress were carried out. Several physiological and biochemical parameters increased in stressed plants (i.e., stomatal conductance and flavonoids content), regardless of whether or not they were previously bacterized. Results showed that neither PICF6 (ACD positive) nor PICF7 (ACD negative) lessened the negative effects caused by the abiotic stresses tested, at least under our experimental conditions.
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