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Li L, Li B, Li Q, Wang L, Yang H. Root Endophytic Microorganisms Contribute to the Attribute of Full-Year Shooting in Woody Bamboo Cephalostachyum pingbianense. Microorganisms 2024; 12:1927. [PMID: 39338601 PMCID: PMC11434196 DOI: 10.3390/microorganisms12091927] [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: 08/19/2024] [Revised: 09/18/2024] [Accepted: 09/19/2024] [Indexed: 09/30/2024] Open
Abstract
Cephalostachyum pingbianense (Hsueh & Y.M. Yang ex Yi et al.) D.Z. Li & H.Q. Yang is unique among bamboo species for its ability to produce bamboo shoots in all seasons under natural conditions. Apart from the physiological mechanism, information regarding the effects of endophytic microorganisms on this full-year shooting characteristic is limited. We hypothesize that root endophytic microorganisms will have a positive impact on the full-year bamboo shooting characteristic of C. pingbianense by increasing the availability or supply of nutrients. To identify the seasonal variations in the root endophytic bacterial and fungal communities of C. pingbianense, and to assess their correlation with bamboo shoot productivity, the roots of C. pingbianense were selected as research materials, and the 16S rRNA and ITS rDNA genes of root endophytic microorganisms were sequenced using the Illumina platform. Following this sequencing, raw sequencing reads were processed, and OTUs were annotated. Alpha and beta diversity, microbial composition, and functional predictions were analyzed, with correlations to bamboo shoot numbers assessed. The results showed that seasonal changes significantly affected the community diversity and structure of root endophytic microbes of C. pingbianense. Bacterial communities in root samples from all seasons contained more nitrogen-fixing microorganisms, with members of the Burkholderiales and Rhizobiales predominating. The relative abundances of ectomycorrhizal and arbuscular mycorrhizal fungi in the autumn sample were significantly higher than in other seasons. Correlation analysis revealed that the bamboo shoot productivity was significantly and positively correlated with bacterial functions of nitrogen fixation, arsenate detoxification, and ureolysis, as well as with symbiotrophic fungi, ectomycorrhizal fungi, and arbuscular mycorrhizal fungi. At the genus level, the bacterial genus Herbaspirillum and the fungal genera Russula, unclassified_f_Acaulosporaceae, and unclassified_f_Glomeraceae were found to have a significant positive correlation with bamboo shoot number. Our study provides an ecological perspective for understanding the highly productive attribute of C. pingbianense and offers new insights into the forest management of woody bamboos.
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Affiliation(s)
- Lushuang Li
- Key Laboratory of Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming 650224, China;
- Forestry College, Southwest Forestry University, Kunming 650224, China
| | - Bin Li
- Horticultural Research Institute, Yunnan Academy of Agricultural Sciences, Kunming 650205, China;
| | - Qing Li
- Yunnan Forestry Double Center, Yunnan Forestry and Grassland Bureau, Kunming 650051, China;
| | - Lianchun Wang
- Key Laboratory of Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming 650224, China;
| | - Hanqi Yang
- Institute of Highland Forest Science, Chinese Academy of Forestry, Kunming 650233, China
- Key Laboratory of Breeding and Utilization of Resource Insects, National Forestry and Grassland Administration, Kunming 650233, China
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Liao N, Pan L, Zhao H, Yang S, Qin X, Huang J, Li X, Dong K, Shi X, Hou Q, Chen Q, Wang P, Jiang G, Li N. Species pool and soil properties in mangrove habitats influence the species-immigration process of diazotrophic communities across southern China. mSystems 2024; 9:e0030724. [PMID: 38980055 PMCID: PMC11334429 DOI: 10.1128/msystems.00307-24] [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: 03/18/2024] [Accepted: 06/15/2024] [Indexed: 07/10/2024] Open
Abstract
Microbial immigration is an ecological process in natural environments; however, the ecological trade-off mechanisms that govern the balance between species extinction and migration are still lacking. In this study, we investigated the mechanisms underlying the migration of diazotrophic communities from soil to leaves across six natural mangrove habitats in southern China. The results showed that the diazotrophic alpha and beta diversity exhibited significant regional and locational variations. The diazotrophic species pool gradually increased from the leaves to nonrhizosphere soil at each site, exhibiting a vertical distribution pattern. Mantel test analyses suggested that climate factors, particularly mean annual temperature, significantly influenced the structure of the diazotrophic community. The diazotrophic community assembly was mainly governed by dispersal limitation in soil and root samples, whereas dispersal limitation and ecological drift were dominant in leaves. Partial least squares path modeling revealed that the species pool and soil properties, particularly the oxidation-reduction potential and pH, were closely linked to the species-immigration ratio of diazotrophic communities. Our study provides novel insights for understanding the ecological trait diversity patterns and spread pathways of functional microbial communities between below- and aboveground habitats in natural ecosystems.IMPORTANCEEnvironmental selection plays key roles in microbial transmission. In this study, we have provided a comprehensive framework to elucidate the driving patterns of the ecological trade-offs in diazotrophic communities across large-scale mangrove habitats. Our research revealed that Bradyrhizobium japonicum, Marinobacterium lutimaris, and Agrobacterium tumefaciens were more abundant in root-associated soil than in leaves by internal and external pathways. The nonrhizospheric and rhizospheric soil samples harbored the most core amplicon sequence variants, indicating that these dominant diazotrophs could adapt to broader ecological niches. Correlation analysis indicated that the diversities of the diazotrophic community were regulated by biotic and abiotic factors. Furthermore, this study found a lower species immigration ratio in the soil than in the leaves. Both species pool and soil properties regulate the species-immigration mechanisms of the diazotrophic community. These results suggest that substantial species immigration is a widespread ecological process, leading to alterations in local community diversity across diverse host environments.
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Affiliation(s)
- Nengjian Liao
- Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, China
- Key Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Guangdong Ocean University, Zhanjiang, China
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin, China
| | - Lianghao Pan
- Guangxi Key Lab of Mangrove Conservation and Utilization, Guangxi Academy of Marine Sciences (Guangxi Mangrove Research Center), Guangxi Academy of Sciences, Beihai, China
| | - Huaxian Zhao
- Key Laboratory of Environment Change and Resources Use in Beibu Gulf, Ministry of Education (Nanning Normal University), Nanning, China
| | - Shu Yang
- Key Laboratory of Environment Change and Resources Use in Beibu Gulf, Ministry of Education (Nanning Normal University), Nanning, China
| | - Xinyi Qin
- Key Laboratory of Environment Change and Resources Use in Beibu Gulf, Ministry of Education (Nanning Normal University), Nanning, China
| | | | - Xiaoli Li
- School of Agriculture, Ludong University, Yantai, China
| | - Ke Dong
- Department of Biological Sciences, Kyonggi University, Suwon-si, Gyeonggi-do, South Korea
| | - Xiaofang Shi
- Guangxi Key Lab of Mangrove Conservation and Utilization, Guangxi Academy of Marine Sciences (Guangxi Mangrove Research Center), Guangxi Academy of Sciences, Beihai, China
- Key Laboratory of the Coastal and Wetland Ecosystems (Xiamen University), Ministry of Education, College of the Environment and Ecology, Xiamen University, Xiamen, China
| | - Qinghua Hou
- Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, China
| | - Qingxiang Chen
- Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, China
| | - Pengbin Wang
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Gonglingxia Jiang
- Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, China
| | - Nan Li
- Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, China
- Key Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Guangdong Ocean University, Zhanjiang, China
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Ramos Cabrera EV, Delgado Espinosa ZY, Solis Pino AF. Use of Phosphorus-Solubilizing Microorganisms as a Biotechnological Alternative: A Review. Microorganisms 2024; 12:1591. [PMID: 39203433 PMCID: PMC11356295 DOI: 10.3390/microorganisms12081591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2024] [Revised: 07/24/2024] [Accepted: 08/01/2024] [Indexed: 09/03/2024] Open
Abstract
Microorganisms with the ability to dissolve phosphorus have the potential to release this essential nutrient into the soil through natural solubilization processes, which allows for boosting plant growth and development. While literature reviews acknowledge their potential, unexplored territories concerning accessibility, application, and effective integration into sustainable agriculture necessitate further research. This manuscript employed distinct methodologies to execute a bibliometric analysis and a literature review. The combined application of both methodologies enables a holistic understanding of the domain landscape and its innovative facets. For the bibliometric analysis, the propositions of Donthu and Jia were utilized, supplemented by tools, such as Bibliometrix. The literature review adhered to a systematic methodology predicated on Petersen's guidelines to represent the domain accurately, pinpointing trends and gaps that could steer future, more detailed research. This investigation uncovers an escalating interest in studying these microorganisms since the 2000s, emphasizing their significance in sustainable agriculture and the context of phosphorus scarcity. It was also discerned that India and China, nations with notable agricultural sectors and a high demand for phosphorus fertilizers, spearheaded research output on this subject. This signifies their substantial contribution to the progression of this scientific field. Furthermore, according to the research consulted, phosphorus-solubilizing microorganisms play a pivotal role in the symbiotic interaction of soil with plant roots and represent an efficacious strategy to counteract the low availability of phosphorus in the soil and sustainably enhance agricultural systems. Finally, this review contributes to the relevant domain by examining existing empirical evidence with special emphasis on sustainable agriculture, improved understanding of phosphorus solubilization mechanisms, and recognition of various microbial entities.
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Affiliation(s)
- Efrén Venancio Ramos Cabrera
- Escuela de Ciencias Agrícolas, Pecuarias y del Medio Ambiente—ECAPMA, Universidad Nacional Abierta y a Distancia—UNAD, Calle 5 # 46N-67, Popayán 190001, Cauca, Colombia;
| | - Zuly Yuliana Delgado Espinosa
- Facultad de Ingeniería, Corporación Universitaria Comfacauca—Unicomfacauca, Cl. 4 N. 8-30, Popayán 190001, Cauca, Colombia;
| | - Andrés Felipe Solis Pino
- Facultad de Ingeniería, Corporación Universitaria Comfacauca—Unicomfacauca, Cl. 4 N. 8-30, Popayán 190001, Cauca, Colombia;
- Facultad de Ingeniería Electrónica y Telecomunicaciones, Universidad del Cauca, Popayán 190003, Cauca, Colombia
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Pal G, Saxena S, Kumar K, Verma A, Kumar D, Shukla P, Pandey A, White J, Verma SK. Seed endophytic bacterium Lysinibacillus sp. (ZM1) from maize (Zea mays L.) shapes its root architecture through modulation of auxin biosynthesis and nitrogen metabolism. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2024; 212:108731. [PMID: 38761545 DOI: 10.1016/j.plaphy.2024.108731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2024] [Revised: 04/25/2024] [Accepted: 05/13/2024] [Indexed: 05/20/2024]
Abstract
Seed endophytic bacteria have been shown to promote the growth and development of numerous plants. However, the underlying mechanism still needs to be better understood. The present study aims to investigate the role of a seed endophytic bacterium Lysinibacillus sp. (ZM1) in promoting plant growth and shaping the root architecture of maize seedlings. The study explores how bacteria-mediated auxin biosynthesis and nitrogen metabolism affect plant growth promotion and shape the root architecture of maize seedlings. The results demonstrate that ZM1 inoculation significantly enhances root length, root biomass, and the number of seminal roots in maize seedlings. Additionally, the treated seedlings exhibit increased shoot biomass and higher levels of photosynthetic pigments. Confocal laser scanning microscopy (CLSM) analysis revealed extensive colonization of ZM1 on root hairs, as well as in the cortical and stellar regions of the root. Furthermore, LC-MS analysis demonstrated elevated auxin content in the roots of the ZM1 treated maize seedlings compared to the uninoculated control. Inoculation with ZM1 significantly increased the levels of endogenous ammonium content, GS, and GOGAT enzyme activities in the roots of treated maize seedlings compared to the control, indicating enhanced nitrogen metabolism. Furthermore, inoculation of bacteria under nitrogen-deficient conditions enhanced plant growth, as evidenced by increased root shoot length, fresh and dry weights, average number of seminal roots, and content of photosynthetic pigments. Transcript analysis indicated upregulation of auxin biosynthetic genes, along with genes involved in nitrogen metabolism at different time points in roots of ZM1-treated maize seedlings. Collectively, our findings highlight the positive impact of Lysinibacillus sp. ZM1 inoculation on maize seeds by improving root architecture through modulation of auxin biosynthesis and affecting various nitrogen metabolism related parameters. These findings provide valuable insights into the potential utilization of seed endophytic bacteria as biofertilizers to enhance plant growth and yield in nutrient deficient soils.
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Affiliation(s)
- Gaurav Pal
- Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi, Uttar Pradesh, 221005, India; Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, 276957612, USA.
| | - Samiksha Saxena
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Kanchan Kumar
- Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi, Uttar Pradesh, 221005, India
| | - Anand Verma
- Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi, Uttar Pradesh, 221005, India
| | - Deepak Kumar
- Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi, Uttar Pradesh, 221005, India
| | - Pooja Shukla
- Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi, Uttar Pradesh, 221005, India
| | - Ashutosh Pandey
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - James White
- Department of Plant Biology, Rutgers University, New Brunswick, NJ, USA
| | - Satish K Verma
- Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi, Uttar Pradesh, 221005, India.
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Alam M, Pandit B, Moin A, Iqbal UN. Invisible Inhabitants of Plants and a Sustainable Planet: Diversity of Bacterial Endophytes and their Potential in Sustainable Agriculture. Indian J Microbiol 2024; 64:343-366. [PMID: 39011025 PMCID: PMC11246410 DOI: 10.1007/s12088-024-01225-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 02/07/2024] [Indexed: 07/17/2024] Open
Abstract
Uncontrolled usage of chemical fertilizers, climate change due to global warming, and the ever-increasing demand for food have necessitated sustainable agricultural practices. Removal of ever-increasing environmental pollutants, treatment of life-threatening diseases, and control of drug-resistant pathogens are also the need of the present time to maintain the health and hygiene of nature, as well as human beings. Research on plant-microbe interactions is paving the way to ameliorate all these sustainably. Diverse bacterial endophytes inhabiting the internal tissues of different parts of the plants promote the growth and development of their hosts by different mechanisms, such as through nutrient acquisition, phytohormone production and modulation, protection from biotic or abiotic challenges, assisting in flowering and root development, etc. Notwithstanding, efficient exploitation of endophytes in human welfare is hindered due to scarce knowledge of the molecular aspects of their interactions, community dynamics, in-planta activities, and their actual functional potential. Modern "-omics-based" technologies and genetic manipulation tools have empowered scientists to explore the diversity, dynamics, roles, and functional potential of endophytes, ultimately empowering humans to better use them in sustainable agricultural practices, especially in future harsh environmental conditions. In this review, we have discussed the diversity of bacterial endophytes, factors (biotic as well as abiotic) affecting their diversity, and their various plant growth-promoting activities. Recent developments and technological advancements for future research, such as "-omics-based" technologies, genetic engineering, genome editing, and genome engineering tools, targeting optimal utilization of the endophytes in sustainable agricultural practices, or other purposes, have also been discussed.
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Affiliation(s)
- Masrure Alam
- Microbial Ecology and Physiology Lab, Department of Biological Sciences, Aliah University, IIA/27 New Town, Kolkata, West Bengal 700160 India
| | - Baishali Pandit
- Microbial Ecology and Physiology Lab, Department of Biological Sciences, Aliah University, IIA/27 New Town, Kolkata, West Bengal 700160 India
- Department of Botany, Surendranath College, 24/2 MG Road, Kolkata, West Bengal 700009 India
| | - Abdul Moin
- Microbial Ecology and Physiology Lab, Department of Biological Sciences, Aliah University, IIA/27 New Town, Kolkata, West Bengal 700160 India
| | - Umaimah Nuzhat Iqbal
- Microbial Ecology and Physiology Lab, Department of Biological Sciences, Aliah University, IIA/27 New Town, Kolkata, West Bengal 700160 India
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Sena L, Mica E, Valè G, Vaccino P, Pecchioni N. Exploring the potential of endophyte-plant interactions for improving crop sustainable yields in a changing climate. FRONTIERS IN PLANT SCIENCE 2024; 15:1349401. [PMID: 38571718 PMCID: PMC10988515 DOI: 10.3389/fpls.2024.1349401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 03/05/2024] [Indexed: 04/05/2024]
Abstract
Climate change poses a major threat to global food security, significantly reducing crop yields as cause of abiotic stresses, and for boosting the spread of new and old pathogens and pests. Sustainable crop management as a route to mitigation poses the challenge of recruiting an array of solutions and tools for the new aims. Among these, the deployment of positive interactions between the micro-biotic components of agroecosystems and plants can play a highly significant role, as part of the agro-ecological revolution. Endophytic microorganisms have emerged as a promising solution to tackle this challenge. Among these, Arbuscular Mycorrhizal Fungi (AMF) and endophytic bacteria and fungi have demonstrated their potential to alleviate abiotic stresses such as drought and heat stress, as well as the impacts of biotic stresses. They can enhance crop yields in a sustainable way also by other mechanisms, such as improving the nutrient uptake, or by direct effects on plant physiology. In this review we summarize and update on the main types of endophytes, we highlight several studies that demonstrate their efficacy in improving sustainable yields and explore possible avenues for implementing crop-microbiota interactions. The mechanisms underlying these interactions are highly complex and require a comprehensive understanding. For this reason, omic technologies such as genomics, transcriptomics, proteomics, and metabolomics have been employed to unravel, by a higher level of information, the complex network of interactions between plants and microorganisms. Therefore, we also discuss the various omic approaches and techniques that have been used so far to study plant-endophyte interactions.
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Affiliation(s)
- Lorenzo Sena
- Dipartimento di Scienze della Vita, Sede Agraria, UNIMORE - Università di Modena e Reggio Emilia, Reggio Emilia, Italy
- Centro di Ricerca Cerealicoltura e Colture Industriali, CREA – Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria, Vercelli, Italy
| | - Erica Mica
- Dipartimento per lo Sviluppo Sostenibile e la Transizione Ecologica, UPO – Università del Piemonte Orientale, Complesso San Giuseppe, Vercelli, Italy
| | - Giampiero Valè
- Dipartimento per lo Sviluppo Sostenibile e la Transizione Ecologica, UPO – Università del Piemonte Orientale, Complesso San Giuseppe, Vercelli, Italy
| | - Patrizia Vaccino
- Centro di Ricerca Cerealicoltura e Colture Industriali, CREA – Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria, Vercelli, Italy
| | - Nicola Pecchioni
- Dipartimento di Scienze della Vita, Sede Agraria, UNIMORE - Università di Modena e Reggio Emilia, Reggio Emilia, Italy
- Centro di Ricerca Cerealicoltura e Colture Industriali, CREA – Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria, Vercelli, Italy
- Centro di Ricerca Cerealicoltura e Colture Industriali, CREA – Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria, Foggia, Italy
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Liu Y, Xu Z, Chen L, Xun W, Shu X, Chen Y, Sun X, Wang Z, Ren Y, Shen Q, Zhang R. Root colonization by beneficial rhizobacteria. FEMS Microbiol Rev 2024; 48:fuad066. [PMID: 38093453 PMCID: PMC10786197 DOI: 10.1093/femsre/fuad066] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 12/07/2023] [Accepted: 12/12/2023] [Indexed: 01/13/2024] Open
Abstract
Rhizosphere microbes play critical roles for plant's growth and health. Among them, the beneficial rhizobacteria have the potential to be developed as the biofertilizer or bioinoculants for sustaining the agricultural development. The efficient rhizosphere colonization of these rhizobacteria is a prerequisite for exerting their plant beneficial functions, but the colonizing process and underlying mechanisms have not been thoroughly reviewed, especially for the nonsymbiotic beneficial rhizobacteria. This review systematically analyzed the root colonizing process of the nonsymbiotic rhizobacteria and compared it with that of the symbiotic and pathogenic bacteria. This review also highlighted the approaches to improve the root colonization efficiency and proposed to study the rhizobacterial colonization from a holistic perspective of the rhizosphere microbiome under more natural conditions.
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Affiliation(s)
- Yunpeng Liu
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, The Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, 12 Zhongguancun South Street, Beijing 100081, P.R. China
| | - Zhihui Xu
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-Based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, 6 Tongwei Road, Nanjing 210095, P.R. China
| | - Lin Chen
- Experimental Center of Forestry in North China, Chinese Academy of Forestry, 1 Shuizha West Road, Beijing 102300, P.R. China
| | - Weibing Xun
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-Based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, 6 Tongwei Road, Nanjing 210095, P.R. China
| | - Xia Shu
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, The Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, 12 Zhongguancun South Street, Beijing 100081, P.R. China
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, 1 Shizishan Street, Wuhan, P.R. China
| | - Yu Chen
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-Based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, 6 Tongwei Road, Nanjing 210095, P.R. China
| | - Xinli Sun
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-Based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, 6 Tongwei Road, Nanjing 210095, P.R. China
| | - Zhengqi Wang
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-Based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, 6 Tongwei Road, Nanjing 210095, P.R. China
| | - Yi Ren
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-Based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, 6 Tongwei Road, Nanjing 210095, P.R. China
| | - Qirong Shen
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-Based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, 6 Tongwei Road, Nanjing 210095, P.R. China
| | - Ruifu Zhang
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, The Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, 12 Zhongguancun South Street, Beijing 100081, P.R. China
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-Based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, 6 Tongwei Road, Nanjing 210095, P.R. China
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Akbaba M, Özden E. Salt tolerance of endophytic root bacteria and their effects on seed germination and viability on tomato plants. Braz J Microbiol 2023; 54:3147-3162. [PMID: 37768522 PMCID: PMC10689620 DOI: 10.1007/s42770-023-01127-7] [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: 04/10/2023] [Accepted: 09/09/2023] [Indexed: 09/29/2023] Open
Abstract
Salinity is one of the most brutal environmental factors limiting the productivity of agricultural lands worldwide. It is considered that the salinity may be one of the important reasons for the low yield in Iğdır of the tomato plants, which is medium resistant (3-5 dS.m-1) among vegetables. Eco-friendly techniques such as endophytic root bacteria treatments (ERB) are needed to restore saline soils to agriculture and also to increase the yield of tomatoes. Endophytic bacteria colonizing the inside of plants increase plant growth by various mechanisms and also mitigate the adverse effects of biotic and abiotic stresses on plants. In this study, endophytic bacteria were isolated from the roots of tomato plants exposed to salt stress. Then, these isolates' tolerance levels to different NaCl (0, 0.1, 0.2, 0.4, 0.8 M) concentrations and their potential to promote plant growth (PGP) traits were determined. It was recorded that 14.8% of the isolates whose salt tolerance was tested were highly tolerant to NaCl and 18.5% were highly susceptible. The tested ERB isolates exhibited typical PGP characteristics such as siderophore production (4-30 mm diameter), phosphate solubilizing activity (6-16 mm diameter), and IAA production activity (24.9-171.6 µg/ml). Moreover, it was determined that the nitrogen fixation potential is high 55.7% of the isolates tested, and 11.1% low. In addition, the effects of ERB treatments on germination and vigor index in two tomato cultivars under standard and saline conditions in the lab were evaluated. Some ERB isolates in tomato plants under standard and saline conditions increased seed viability, hypocotyl length, root length, and seedling fresh weight, and also accelerated germination.
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Affiliation(s)
- Mustafa Akbaba
- Plant Protection, Faculty of Agriculture, Igdir University, Igdir, Turkey.
| | - Eren Özden
- Horticulture, Faculty of Agriculture, Igdir University, Igdir, Turkey
- Horticulture and Agronomy, Faculty of Agriculture, Kyrgyz-Turkish Manas University, Bishkek, Kyrgyz Republic
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Kan Y, Zhang L, Wang Y, Ma Q, Zhou Y, Jiang X, Zhang W, Ruan Z. Endophytic Bacterium Flexivirga meconopsidis sp. nov. with Plant Growth-Promoting Function, Isolated from the Seeds of Meconopsis integrifolia. Microorganisms 2023; 11:2899. [PMID: 38138043 PMCID: PMC10745605 DOI: 10.3390/microorganisms11122899] [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: 10/16/2023] [Revised: 11/25/2023] [Accepted: 11/29/2023] [Indexed: 12/24/2023] Open
Abstract
Strain Q11T of an irregular coccoid Gram-positive bacterium, aerobic and non-motile, was isolated from Meconopsis integrifolia seeds. Strain Q11T grew optimally in 1% (w/v) NaCl, pH 7, at 30 °C. Strain Q11T is most closely related to Flexivirga, as evidenced by 16S rRNA gene analysis, and shares the highest similarity with Flexivirga aerilata ID2601ST (99.24%). Based on genome sequence analysis, the average nucleotide identity and digital DNA-DNA hybridization values of strains Q11T and D2601ST were 88.82% and 36.20%, respectively. Additionally, strain Q11T showed the abilities of nitrogen fixation and indole acetic acid production and was shown to promote maize growth under laboratory conditions. Its genome contains antibiotic resistance genes (the vanY gene in the vanB cluster and the vanW gene in the vanI cluster) and extreme environment tolerance genes (ectoine biosynthetic gene cluster). Shotgun proteomics also detected antibiotic resistance proteins (class A beta-lactamases, D-alanine ligase family proteins) and proteins that improve plant cold tolerance (multispecies cold shock proteins). Strain Q11T was determined to be a novel species of the genus Flexivirga, for which the name Flexivirga meconopsidis sp. nov. is proposed. The strain type is Q11T (GDMCC 1.3002T = JCM 36020 T).
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Affiliation(s)
- Yongtao Kan
- College of Life Sciences, Xinjiang Normal University, Urumqi 830017, China;
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.W.); (Q.M.); (Y.Z.); (X.J.)
- CAAS-CIAT Joint Laboratory in Advanced Technologies for Sustainable Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Li Zhang
- College of Life Sciences, Yantai University, Yantai 264005, China;
| | - Yan Wang
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.W.); (Q.M.); (Y.Z.); (X.J.)
- CAAS-CIAT Joint Laboratory in Advanced Technologies for Sustainable Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- College of Resources and Environment, Tibet Agricultural and Animal Husbandry University, Linzhi 860000, China
| | - Qingyun Ma
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.W.); (Q.M.); (Y.Z.); (X.J.)
- CAAS-CIAT Joint Laboratory in Advanced Technologies for Sustainable Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Yiqing Zhou
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.W.); (Q.M.); (Y.Z.); (X.J.)
- CAAS-CIAT Joint Laboratory in Advanced Technologies for Sustainable Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Xu Jiang
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.W.); (Q.M.); (Y.Z.); (X.J.)
- CAAS-CIAT Joint Laboratory in Advanced Technologies for Sustainable Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Wei Zhang
- College of Life Sciences, Xinjiang Normal University, Urumqi 830017, China;
| | - Zhiyong Ruan
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.W.); (Q.M.); (Y.Z.); (X.J.)
- CAAS-CIAT Joint Laboratory in Advanced Technologies for Sustainable Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
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10
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Ebu SM, Adem MA, Dekebo A, Olani A. Isolation and Identification of Endophytic Bacterial Isolates from the Leaves, Roots, and Stems Parts of Artemisia annua, Moringa oleifera, and Ocimum lamiifolium Plants. Curr Microbiol 2023; 80:405. [PMID: 37930451 DOI: 10.1007/s00284-023-03513-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 10/04/2023] [Indexed: 11/07/2023]
Abstract
Medicinal plants are known to harbor diverse species of endophytic bacteria which are known for secretion of beneficial secondary metabolites, like enzymes and antimicrobial compounds. The present study aimed to isolate, characterize, and identify the endophytic bacteria isolates from Artemisia annua, Moringa oleifera, and Ocimum lamiifolium plants. Certain endophytic bacterial isolates were screened. Phosphate and Zinc solubilization were performed for newly obtained isolates. The 16S rRNA gene sequencing was performed for RPAAI-8 isolate. Data were analyzed. Our study showed that endophytic bacterial isolates were recognized to be Bacillus cereus, B. subtilis, Citrobacter freundii, Enterobacter asburiae, E. cloacae, E. kobei, E. ludwigii, Enterococcus faecium, and Pseudomonas monteilli. From among these differentiated endophytic bacterial isolates, Enterobacter species are the most frequently obtained isolates. These bacterial isolates were shown 99.77% sequence similarity to Enterobacter ludwigii EN-119T (JTLO01000001) using 16S rRNA gene sequencing. This isolate was designated as Enterobacter sp. RPAAI-8. This isolate was able to employ selected cheap and cost-effective agro wastes as a carbon source. This cheap agro waste utilization by these Enterobacter species could be the first report. In conclusion, the present isolates are found to be employed for plant growth promotion and solubilizing insoluble phosphate and zinc. Before this time, most of the recent isolates were not identified from these medicinal plants. The ethyl acetate extract of the isolates also showed inhibitory activity against selected test pathogens.
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Affiliation(s)
- Seid Mohammed Ebu
- Department of Applied Biology, Adama Science and Technology University, Adama, Oromia, Ethiopia.
| | - Muktar Ahmed Adem
- Department of Applied Biology, Adama Science and Technology University, Adama, Oromia, Ethiopia
| | - Aman Dekebo
- Department of Applied Chemistry, Adama Science and Technology University, Adama, Oromia, Ethiopia
| | - Ababe Olani
- Istitute of Biotechnology, Sebeta, Oromia, Ethiopia
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11
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Jhu MY, Oldroyd GED. Dancing to a different tune, can we switch from chemical to biological nitrogen fixation for sustainable food security? PLoS Biol 2023; 21:e3001982. [PMID: 36917569 PMCID: PMC10013914 DOI: 10.1371/journal.pbio.3001982] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Our current food production systems are unsustainable, driven in part through the application of chemically fixed nitrogen. We need alternatives to empower farmers to maximise their productivity sustainably. Therefore, we explore the potential for transferring the root nodule symbiosis from legumes to other crops. Studies over the last decades have shown that preexisting developmental and signal transduction processes were recruited during the evolution of legume nodulation. This allows us to utilise these preexisting processes to engineer nitrogen fixation in target crops. Here, we highlight our understanding of legume nodulation and future research directions that might help to overcome the barrier of achieving self-fertilising crops.
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Affiliation(s)
- Min-Yao Jhu
- Crop Science Centre, Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Giles E. D. Oldroyd
- Crop Science Centre, Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
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12
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Acosta K, Sorrels S, Chrisler W, Huang W, Gilbert S, Brinkman T, Michael TP, Lebeis SL, Lam E. Optimization of Molecular Methods for Detecting Duckweed-Associated Bacteria. PLANTS (BASEL, SWITZERLAND) 2023; 12:872. [PMID: 36840219 PMCID: PMC9965182 DOI: 10.3390/plants12040872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/05/2023] [Accepted: 02/08/2023] [Indexed: 06/18/2023]
Abstract
The bacterial colonization dynamics of plants can differ between phylogenetically similar bacterial strains and in the context of complex bacterial communities. Quantitative methods that can resolve closely related bacteria within complex communities can lead to a better understanding of plant-microbe interactions. However, current methods often lack the specificity to differentiate phylogenetically similar bacterial strains. In this study, we describe molecular strategies to study duckweed-associated bacteria. We first systematically optimized a bead-beating protocol to co-isolate nucleic acids simultaneously from duckweed and bacteria. We then developed a generic fingerprinting assay to detect bacteria present in duckweed samples. To detect specific duckweed-bacterium associations, we developed a genomics-based computational pipeline to generate bacterial strain-specific primers. These strain-specific primers differentiated bacterial strains from the same genus and enabled the detection of specific duckweed-bacterium associations present in a community context. Moreover, we used these strain-specific primers to quantify the bacterial colonization of duckweed by normalization to a plant reference gene and revealed differences in colonization levels between strains from the same genus. Lastly, confocal microscopy of inoculated duckweed further supported our PCR results and showed bacterial colonization of the duckweed root-frond interface and root interior. The molecular methods introduced in this work should enable the tracking and quantification of specific plant-microbe associations within plant-microbial communities.
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Affiliation(s)
- Kenneth Acosta
- Department of Plant Biology, Rutgers the State University of New Jersey, New Brunswick, NJ 08901, USA
| | - Shawn Sorrels
- Department of Plant Biology, Rutgers the State University of New Jersey, New Brunswick, NJ 08901, USA
| | - William Chrisler
- Environmental Molecular Sciences Laboratory (EMSL), Pacific Northwest National Laboratory (PNNL), Richland, WA 99354, USA
| | - Weijuan Huang
- Institute of Nanfan & Seed Industry, Guangdong Academy of Sciences, Guangzhou 510316, China
| | - Sarah Gilbert
- Department of Plant Biology, Rutgers the State University of New Jersey, New Brunswick, NJ 08901, USA
| | - Thomas Brinkman
- Department of Plant Biology, Rutgers the State University of New Jersey, New Brunswick, NJ 08901, USA
| | - Todd P. Michael
- The Plant Molecular and Cellular Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Sarah L. Lebeis
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824, USA
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA
- Plant Resilience Institute, Michigan State University, East Lansing, MI 48824, USA
| | - Eric Lam
- Department of Plant Biology, Rutgers the State University of New Jersey, New Brunswick, NJ 08901, USA
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13
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Li Y, Yang R, Häggblom MM, Li M, Guo L, Li B, Kolton M, Cao Z, Soleimani M, Chen Z, Xu Z, Gao W, Yan B, Sun W. Characterization of diazotrophic root endophytes in Chinese silvergrass (Miscanthus sinensis). MICROBIOME 2022; 10:186. [PMID: 36329505 PMCID: PMC9632085 DOI: 10.1186/s40168-022-01379-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 09/22/2022] [Indexed: 05/23/2023]
Abstract
BACKGROUND Phytoremediation is a potentially cost-effective way to remediate highly contaminated mine tailing sites. However, nutrient limitations, especially the deficiency of nitrogen (N), can hinder the growth of plants and impair the phytoremediation of mine tailings. Nevertheless, pioneer plants can successfully colonize mine tailings and exhibit potential for tailing phytoremediation. Diazotrophs, especially diazotrophic endophytes, can promote the growth of their host plants. This was tested in a mine-tailing habitat by a combination of field sampling, DNA-stable isotope probing (SIP) analysis, and pot experiments. RESULTS Bacteria belonging to the genera Herbaspirillum, Rhizobium, Devosia, Pseudomonas, Microbacterium, and Delftia are crucial endophytes for Chinese silvergrass (Miscanthus sinensis) grown in the tailing, the model pioneer plant selected in this study. Further, DNA-SIP using 15N2 identified Pseudomonas, Rhizobium, and Exiguobacterium as putative diazotrophic endophytes of M. sinensis. Metagenomic-binning suggested that these bacteria contained essential genes for nitrogen fixation and plant growth promotion. Finally, two diazotrophic endophytes Rhizobium sp. G-14 and Pseudomonas sp. Y-5 were isolated from M. sinensis. Inoculation of another pioneer plant in mine tailings, Bidens pilosa, with diazotrophic endophytes resulted in successful plant colonization, significantly increased nitrogen fixation activity, and promotion of plant growth. CONCLUSIONS This study indicated that diazotrophic endophytes have the potential to promote the growth of pioneer plant B. pilosa in mine tailings. Video Abstract.
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Affiliation(s)
- Yongbin Li
- Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Academy of Sciences, Guangzhou, 510650, China
- Joint Laboratory for Environmental Pollution and Control, Guangdong-Hong Kong-Macao, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Rui Yang
- Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Academy of Sciences, Guangzhou, 510650, China
| | - Max M Häggblom
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Mengyan Li
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, NJ, 07102, USA
| | - Lifang Guo
- Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Academy of Sciences, Guangzhou, 510650, China
| | - Baoqin Li
- Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Academy of Sciences, Guangzhou, 510650, China
| | - Max Kolton
- Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Academy of Sciences, Guangzhou, 510650, China
- Joint Laboratory for Environmental Pollution and Control, Guangdong-Hong Kong-Macao, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
- French Associates Institute for Agriculture and Biotechnology of Drylands, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Zhiguo Cao
- School of Environment, Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Normal University, Xinxiang, 453007, China
| | - Mohsen Soleimani
- Department of Natural Resources, Isfahan University of Technology, Isfahan, Iran
| | - Zheng Chen
- Department of Health and Environmental Sciences, Xi'an Jiaotong-Liverpool University, Suzhou, 215123, China
| | - Zhimin Xu
- Engineering and Technology Research Center for Agricultural Land Pollution Prevention and Control of Guangdong Higher Education Institutes, College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou, 510225, China
| | - Wenlong Gao
- Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Academy of Sciences, Guangzhou, 510650, China
- Joint Laboratory for Environmental Pollution and Control, Guangdong-Hong Kong-Macao, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Bei Yan
- Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Academy of Sciences, Guangzhou, 510650, China
- Joint Laboratory for Environmental Pollution and Control, Guangdong-Hong Kong-Macao, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Weimin Sun
- Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Academy of Sciences, Guangzhou, 510650, China.
- Joint Laboratory for Environmental Pollution and Control, Guangdong-Hong Kong-Macao, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
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14
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Jiang X, Pees T, Reinhold-Hurek B. Deep-learning-based removal of autofluorescence and fluorescence quantification in plant-colonizing bacteria in vivo. THE NEW PHYTOLOGIST 2022; 235:2481-2495. [PMID: 35752974 DOI: 10.1111/nph.18344] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Accepted: 06/19/2022] [Indexed: 06/15/2023]
Abstract
Fluorescence microscopy is common in bacteria-plant interaction studies. However, strong autofluorescence from plant tissues impedes in vivo studies on endophytes tagged with fluorescent proteins. To solve this problem, we developed a deep-learning-based approach to eliminate plant autofluorescence from fluorescence microscopy images, tested for the model endophyte Azoarcus olearius BH72 colonizing Oryza sativa roots. Micrographs from three channels (tdTomato for gene expression, green fluorescent protein (GFP) and AutoFluorescence (AF)) were processed by a neural network based approach, generating images that simulate the background autofluorescence in the tdTomato channel. After subtracting the model-generated signals from each pixel in the genuine channel, the autofluorescence in the tdTomato channel was greatly reduced or even removed. The deep-learning-based approach can be applied for fluorescence detection and quantification, exemplified by a weakly expressed, a cell-density modulated and a nitrogen-fixation gene in A. olearius. A transcriptional nifH::tdTomato fusion demonstrated stronger induction of nif genes inside roots than outside, suggesting extension of the rhizosphere effect for diazotrophs into the endorhizosphere. The pre-trained convolutional neural network model is easily applied to process other images of the same plant tissues with the same settings. This study showed the high potential of deep-learning-based approaches in image processing. With proper training data and strategies, autofluorescence in other tissues or materials can be removed for broad applications.
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Affiliation(s)
- Xun Jiang
- Department of Microbe-Plant Interactions, CBIB Center for Biomolecular Interactions, Faculty of Biology and Chemistry, University of Bremen, PO Box 33 04 40, D-28334, Bremen, Germany
| | - Tobias Pees
- Department of Microbe-Plant Interactions, CBIB Center for Biomolecular Interactions, Faculty of Biology and Chemistry, University of Bremen, PO Box 33 04 40, D-28334, Bremen, Germany
| | - Barbara Reinhold-Hurek
- Department of Microbe-Plant Interactions, CBIB Center for Biomolecular Interactions, Faculty of Biology and Chemistry, University of Bremen, PO Box 33 04 40, D-28334, Bremen, Germany
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15
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Mathesius U. Are legumes different? Origins and consequences of evolving nitrogen fixing symbioses. JOURNAL OF PLANT PHYSIOLOGY 2022; 276:153765. [PMID: 35952452 DOI: 10.1016/j.jplph.2022.153765] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 07/01/2022] [Accepted: 07/03/2022] [Indexed: 05/14/2023]
Abstract
Nitrogen fixing symbioses between plants and bacteria are ancient and, while not numerous, are formed in diverse lineages of plants ranging from microalgae to angiosperms. One symbiosis stands out as the most widespread one is that between legumes and rhizobia, leading to the formation of nitrogen-fixing nodules. The legume family is one of the largest and most diverse group of plants and legumes have been used by humans since the beginning of agriculture, both as high nitrogen food, as well as pastures and rotation crops. One open question is whether their ability to form a nitrogen-fixing symbiosis has contributed to legumes' success, and whether legumes have any unique characteristics that have made them more diverse and widespread than other groups of plants. This review examines the evolutionary journey that has led to the diversification of legumes, in particular its nitrogen-fixing symbiosis, and asks four questions to investigate which legume traits might have contributed to their success: 1. In what ways do legumes differ from other plant groups that have evolved nitrogen-fixing symbioses? In order to answer this question, the characteristics of the symbioses, and efficiencies of nitrogen fixation are compared between different groups of nitrogen fixing plants. 2. Could certain unique features of legumes be a reason for their success? This section examines the manifestations and possible benefits of a nitrogen-rich 'lifestyle' in legumes. 3. If nitrogen fixation was a reason for such a success, why have some species lost the symbiosis? Formation of symbioses has trade-offs, and while these are less well known for non-legumes, there are known energetic and ecological reasons for loss of symbiotic potential in legumes. 4. What can we learn from the unique traits of legumes for future crop improvements? While exploiting some of the physiological properties of legumes could be used to improve legume breeding, our increasing molecular understanding of the essential regulators of root nodule symbioses raise hope of creating new nitrogen fixing symbioses in other crop species.
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Affiliation(s)
- Ulrike Mathesius
- Division of Plant Sciences, Research School of Biology, The Australian National University, 134 Linnaeus Way, Canberra, ACT, 2601, Australia.
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16
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Carvalho TLG, Rosman AC, Grativol C, de M. Nogueira E, Baldani JI, Hemerly AS. Sugarcane Genotypes with Contrasting Biological Nitrogen Fixation Efficiencies Differentially Modulate Nitrogen Metabolism, Auxin Signaling, and Microorganism Perception Pathways. PLANTS (BASEL, SWITZERLAND) 2022; 11:1971. [PMID: 35956449 PMCID: PMC9370643 DOI: 10.3390/plants11151971] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Revised: 07/19/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
Sugarcane is an economically important crop that is used for the production of fuel ethanol. Diazotrophic bacteria have been isolated from sugarcane tissues, without causing visible plant anatomical changes or disease symptoms. These bacteria can be beneficial to the plant by promoting root growth and an increase in plant yield. Different rates of Biological Nitrogen Fixation (BNF) were observed in different genotypes. The aim of this work was to conduct a comprehensive molecular and physiological analysis of two model genotypes for contrasting BNF efficiency in order to unravel plant genes that are differentially regulated during a natural association with diazotrophic bacteria. A next-generation sequencing of RNA samples from the genotypes SP70-1143 (high-BNF) and Chunee (low-BNF) was performed. A differential transcriptome analysis showed that several pathways were differentially regulated among the two BNF-contrasting genotypes, including nitrogen metabolism, hormone regulation and bacteria recognition. Physiological analyses, such as nitrogenase and GS activity quantification, bacterial colonization, auxin response and root architecture evaluation, supported the transcriptome expression analyses. The differences observed between the genotypes may explain, at least in part, the differences in BNF contributions. Some of the identified genes might be involved in key regulatory processes for a beneficial association and could be further used as tools for obtaining more efficient BNF genotypes.
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Affiliation(s)
- Thais Louise G. Carvalho
- Laboratório de Biologia Molecular de Plantas, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-901, RJ, Brazil; (T.L.G.C.); (A.C.R.); (C.G.); (E.d.M.N.)
| | - Aline C. Rosman
- Laboratório de Biologia Molecular de Plantas, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-901, RJ, Brazil; (T.L.G.C.); (A.C.R.); (C.G.); (E.d.M.N.)
| | - Clícia Grativol
- Laboratório de Biologia Molecular de Plantas, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-901, RJ, Brazil; (T.L.G.C.); (A.C.R.); (C.G.); (E.d.M.N.)
- Laboratório de Química e Funções de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes 28015-622, RJ, Brazil
| | - Eduardo de M. Nogueira
- Laboratório de Biologia Molecular de Plantas, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-901, RJ, Brazil; (T.L.G.C.); (A.C.R.); (C.G.); (E.d.M.N.)
| | - José Ivo Baldani
- Laboratório de Genética e Bioquímica, Centro Nacional de Pesquisa de Agrobiologia, Embrapa Agrobiologia, Rio de Janeiro 23897-970, RJ, Brazil;
| | - Adriana S. Hemerly
- Laboratório de Biologia Molecular de Plantas, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-901, RJ, Brazil; (T.L.G.C.); (A.C.R.); (C.G.); (E.d.M.N.)
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17
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Singh RK, Singh P, Sharma A, Guo DJ, Upadhyay SK, Song QQ, Verma KK, Li DP, Malviya MK, Song XP, Yang LT, Li YR. Unraveling Nitrogen Fixing Potential of Endophytic Diazotrophs of Different Saccharum Species for Sustainable Sugarcane Growth. Int J Mol Sci 2022; 23:ijms23116242. [PMID: 35682919 PMCID: PMC9181200 DOI: 10.3390/ijms23116242] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 05/29/2022] [Accepted: 05/30/2022] [Indexed: 02/06/2023] Open
Abstract
Sugarcane (Saccharum officinarum L.) is one of the world’s highly significant commercial crops. The amounts of synthetic nitrogen (N2) fertilizer required to grow the sugarcane plant at its initial growth stages are higher, which increases the production costs and adverse environmental consequences globally. To combat this issue, sustainable environmental and economic concerns among researchers are necessary. The endophytic diazotrophs can offer significant amounts of nitrogen to crops through the biological nitrogen fixation mediated nif gene. The nifH gene is the most extensively utilized molecular marker in nature for studying N2 fixing microbiomes. The present research intended to determine the existence of novel endophytic diazotrophs through culturable and unculturable bacterial communities (EDBCs). The EDBCs of different tissues (root, stem, and leaf) of five sugarcane cultivars (Saccharum officinarum L. cv. Badila, S. barberi Jesw.cv Pansahi, S. robustum, S. spontaneum, and S. sinense Roxb.cv Uba) were isolated and molecularly characterized to evaluate N2 fixation ability. The diversity of EDBCs was observed based on nifH gene Illumina MiSeq sequencing and a culturable approach. In this study, 319766 operational taxonomic units (OTUs) were identified from 15 samples. The minimum number of OTUs was recorded in leaf tissues of S. robustum and maximum reads in root tissues of S. spontaneum. These data were assessed to ascertain the structure, diversity, abundance, and relationship between the microbial community. A total of 40 bacterial families with 58 genera were detected in different sugarcane species. Bacterial communities exhibited substantially different alpha and beta diversity. In total, 16 out of 20 genera showed potent N2-fixation in sugarcane and other crops. According to principal component analysis (PCA) and hierarchical clustering (Bray–Curtis dis) evaluation of OTUs, bacterial microbiomes associated with root tissues differed significantly from stem and leaf tissues of sugarcane. Significant differences often were observed in EDBCs among the sugarcane tissues. We tracked and validated the plethora of individual phylum strains and assessed their nitrogenase activity with a culture-dependent technique. The current work illustrated the significant and novel results of many uncharted endophytic microbial communities in different tissues of sugarcane species, which provides an experimental system to evaluate the biological nitrogen fixation (BNF) mechanism in sugarcane. The novel endophytic microbial communities with N2-fixation ability play a remarkable and promising role in sustainable agriculture production.
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Affiliation(s)
- Rajesh Kumar Singh
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture, Sugarcane Research Center, Chinese Academy of Agricultural Sciences, Guangxi Key Laboratory of Sugarcane Genetic Improvement, Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China; (R.K.S.); (A.S.); (D.-J.G.); (K.K.V.); (M.K.M.)
- Guangxi Key Laboratory of Crop Genetic Improvement and Biotechnology, Nanning 530007, China; (X.-P.S.); (L.-T.Y.)
| | - Pratiksha Singh
- School of Marine Sciences and Biotechnology, Guangxi University for Nationalities, Nanning 530008, China;
| | - Anjney Sharma
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture, Sugarcane Research Center, Chinese Academy of Agricultural Sciences, Guangxi Key Laboratory of Sugarcane Genetic Improvement, Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China; (R.K.S.); (A.S.); (D.-J.G.); (K.K.V.); (M.K.M.)
- Guangxi Key Laboratory of Crop Genetic Improvement and Biotechnology, Nanning 530007, China; (X.-P.S.); (L.-T.Y.)
| | - Dao-Jun Guo
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture, Sugarcane Research Center, Chinese Academy of Agricultural Sciences, Guangxi Key Laboratory of Sugarcane Genetic Improvement, Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China; (R.K.S.); (A.S.); (D.-J.G.); (K.K.V.); (M.K.M.)
- College of Agriculture, State Key Laboratory of Conservation and Utilization of Subtropical Agro-bio Resources, Guangxi University, Nanning 530005, China
| | - Sudhir K. Upadhyay
- Department of Environmental Science, V.B.S. Purvanchal University, Jaunpur 222003, India;
| | - Qi-Qi Song
- Guangxi Subtropical Crop Research Institute, Sugarcane Research Institute, Nanning 530001, China;
| | - Krishan K. Verma
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture, Sugarcane Research Center, Chinese Academy of Agricultural Sciences, Guangxi Key Laboratory of Sugarcane Genetic Improvement, Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China; (R.K.S.); (A.S.); (D.-J.G.); (K.K.V.); (M.K.M.)
- Guangxi Key Laboratory of Crop Genetic Improvement and Biotechnology, Nanning 530007, China; (X.-P.S.); (L.-T.Y.)
| | - Dong-Ping Li
- Microbiology Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China;
| | - Mukesh Kumar Malviya
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture, Sugarcane Research Center, Chinese Academy of Agricultural Sciences, Guangxi Key Laboratory of Sugarcane Genetic Improvement, Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China; (R.K.S.); (A.S.); (D.-J.G.); (K.K.V.); (M.K.M.)
- Guangxi Key Laboratory of Crop Genetic Improvement and Biotechnology, Nanning 530007, China; (X.-P.S.); (L.-T.Y.)
| | - Xiu-Peng Song
- Guangxi Key Laboratory of Crop Genetic Improvement and Biotechnology, Nanning 530007, China; (X.-P.S.); (L.-T.Y.)
| | - Li-Tao Yang
- Guangxi Key Laboratory of Crop Genetic Improvement and Biotechnology, Nanning 530007, China; (X.-P.S.); (L.-T.Y.)
- College of Agriculture, State Key Laboratory of Conservation and Utilization of Subtropical Agro-bio Resources, Guangxi University, Nanning 530005, China
| | - Yang-Rui Li
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture, Sugarcane Research Center, Chinese Academy of Agricultural Sciences, Guangxi Key Laboratory of Sugarcane Genetic Improvement, Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China; (R.K.S.); (A.S.); (D.-J.G.); (K.K.V.); (M.K.M.)
- Guangxi Key Laboratory of Crop Genetic Improvement and Biotechnology, Nanning 530007, China; (X.-P.S.); (L.-T.Y.)
- College of Agriculture, State Key Laboratory of Conservation and Utilization of Subtropical Agro-bio Resources, Guangxi University, Nanning 530005, China
- Correspondence: ; Tel.: +86-771-3899033
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18
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Nepel M, Angel R, Borer ET, Frey B, MacDougall AS, McCulley RL, Risch AC, Schütz M, Seabloom EW, Woebken D. Global Grassland Diazotrophic Communities Are Structured by Combined Abiotic, Biotic, and Spatial Distance Factors but Resilient to Fertilization. Front Microbiol 2022; 13:821030. [PMID: 35418962 PMCID: PMC8996192 DOI: 10.3389/fmicb.2022.821030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 02/21/2022] [Indexed: 11/25/2022] Open
Abstract
Grassland ecosystems cover around 37% of the ice-free land surface on Earth and have critical socioeconomic importance globally. As in many terrestrial ecosystems, biological dinitrogen (N2) fixation represents an essential natural source of nitrogen (N). The ability to fix atmospheric N2 is limited to diazotrophs, a diverse guild of bacteria and archaea. To elucidate the abiotic (climatic, edaphic), biotic (vegetation), and spatial factors that govern diazotrophic community composition in global grassland soils, amplicon sequencing of the dinitrogenase reductase gene—nifH—was performed on samples from a replicated standardized nutrient [N, phosphorus (P)] addition experiment in 23 grassland sites spanning four continents. Sites harbored distinct and diverse diazotrophic communities, with most of reads assigned to diazotrophic taxa within the Alphaproteobacteria (e.g., Rhizobiales), Cyanobacteria (e.g., Nostocales), and Deltaproteobacteria (e.g., Desulforomonadales) groups. Likely because of the wide range of climatic and edaphic conditions and spatial distance among sampling sites, only a few of the taxa were present at all sites. The best model describing the variation among soil diazotrophic communities at the OTU level combined climate seasonality (temperature in the wettest quarter and precipitation in the warmest quarter) with edaphic (C:N ratio, soil texture) and vegetation factors (various perennial plant covers). Additionally, spatial variables (geographic distance) correlated with diazotrophic community variation, suggesting an interplay of environmental variables and spatial distance. The diazotrophic communities appeared to be resilient to elevated nutrient levels, as 2–4 years of chronic N and P additions had little effect on the community composition. However, it remains to be seen, whether changes in the community composition occur after exposure to long-term, chronic fertilization regimes.
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Affiliation(s)
- Maximilian Nepel
- Department of Microbiology and Ecosystem Science, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria.,Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
| | - Roey Angel
- Department of Microbiology and Ecosystem Science, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Elizabeth T Borer
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN, United States
| | - Beat Frey
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | | | - Rebecca L McCulley
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY, United States
| | - Anita C Risch
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Martin Schütz
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Eric W Seabloom
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN, United States
| | - Dagmar Woebken
- Department of Microbiology and Ecosystem Science, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
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19
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Powell A, Wilder SL, Housh AB, Scott S, Benoit M, Powell G, Waller S, Guthrie JM, Schueller MJ, Ferrieri RA. Examining effects of rhizobacteria in relieving abiotic crop stresses using carbon-11 radiotracing. PHYSIOLOGIA PLANTARUM 2022; 174:e13675. [PMID: 35316539 PMCID: PMC9310733 DOI: 10.1111/ppl.13675] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 02/24/2022] [Accepted: 03/17/2022] [Indexed: 06/12/2023]
Abstract
In agriculture, plant growth promoting bacteria (PGPB) are increasingly used for reducing environmental stress-related crop losses through mutualistic actions of these microorganisms, activating physiological and biochemical responses, building tolerances within their hosts. Here we report the use of radioactive carbon-11 (t½ 20.4 min) to examine the metabolic and physiological responses of Zea mays to Azospirillum brasilense (HM053) inoculation while plants were subjected to salinity and low nitrogen stresses. Host metabolism of "new" carbon resources (as 11 C) and physiology including [11 C]-photosynthate translocation were measured in response to imposed growth conditions. Salinity stress caused shortened, dense root growth with a 6-fold increase in foliar [11 C]-raffinose, a potent osmolyte. ICP-MS analyses revealed increased foliar Na+ levels at the expense of K+ . HM053 inoculation relieved these effects, reinstating normal root growth, lowering [11 C]-raffinose levels while increasing [11 C]-sucrose and its translocation to the roots. Na+ levels remained elevated with inoculation, but K+ levels were boosted slightly. Low nitrogen stress yielded longer roots possessing high levels of anthocyanins. Metabolic analysis revealed significant shifts in "new" carbon partitioning into the amino acid pool under low nitrogen stress, with significant increases in foliar [11 C]-glutamate, [11 C]-aspartate, and [11 C]-asparagine, a noted osmoprotectant. 11 CO2 fixation and [11 C]-photosynthate translocation also decreased, limiting carbon supply to roots. However, starch levels in roots were reduced under nitrogen limitation, suggesting that carbon repartitioning could be a compensatory action to support root growth. Finally, inoculation with HM053 re-instated normal root growth, reduced anthocyanin, boosted root starch, and returned 11 C-allocation levels back to those of unstressed plants.
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Affiliation(s)
- Avery Powell
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- School of Natural ResourcesUniversity of MissouriColumbiaMissouriUSA
| | - Stacy L. Wilder
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
| | - Alexandra B. Housh
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- Chemistry DepartmentUniversity of MissouriColumbiaMissouriUSA
- Interdisciplinary Plant GroupUniversity of MissouriColumbiaMissouriUSA
| | - Stephanie Scott
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- Department of BiochemistryUniversity of MissouriColumbiaMissouriUSA
| | - Mary Benoit
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- Division of Plant Sciences and TechnologyUniversity of MissouriColumbiaMissouriUSA
| | - Garren Powell
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- Department of BiochemistryUniversity of MissouriColumbiaMissouriUSA
| | - Spenser Waller
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- School of Natural ResourcesUniversity of MissouriColumbiaMissouriUSA
| | - James M. Guthrie
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
| | - Michael J. Schueller
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- Chemistry DepartmentUniversity of MissouriColumbiaMissouriUSA
| | - Richard A. Ferrieri
- Missouri Research Reactor CenterUniversity of MissouriColumbiaMissouriUSA
- Chemistry DepartmentUniversity of MissouriColumbiaMissouriUSA
- Interdisciplinary Plant GroupUniversity of MissouriColumbiaMissouriUSA
- Division of Plant Sciences and TechnologyUniversity of MissouriColumbiaMissouriUSA
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20
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Singh R, Pandey KD, Singh M, Singh SK, Hashem A, Al-Arjani ABF, Abd_Allah EF, Singh PK, Kumar A. Isolation and Characterization of Endophytes Bacterial Strains of Momordica charantia L. and Their Possible Approach in Stress Management. Microorganisms 2022; 10:microorganisms10020290. [PMID: 35208743 PMCID: PMC8877101 DOI: 10.3390/microorganisms10020290] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/11/2022] [Accepted: 01/22/2022] [Indexed: 11/16/2022] Open
Abstract
In the present study, eight endophytic bacterial strains, namely Bacillus licheniformis R1, Bacillus sp. R2, Agrobacterium tumefaciens R6, uncultured bacterium R11, Bacillus subtilis RS3, Bacillus subtilis RS6, uncultured bacterium RS8 and Lysinibacillus fusiformis RS9, were isolated from the root of Momordica charantia L. All the strains, except R6 exhibited positive for IAA production, siderophore production, and phosphate solubilization during plant growth-promoting traits analysis. Strains invariably utilized glucose and sucrose as a carbon source during substrate utilization, while yeast extract, ammonium sulphate, ammonium chloride, glycine, glutamine, and isoleucine as nitrogen sources. In addition, Spectinomycin was found as the most effective during antibiotic sensitivity TEST, followed by Chloramphenicol, Erythromycin, Rifampicin and Kanamycin, while Polymixin B was found least effective, while strains R1, R6, and RS8 were sensitive to all the antibiotics. Strains R1 and RS6 were able to withstand tolerance up to 10% of NaCl. The strains showing resistance against broad-spectrum antibiotics, especially chloramphenicol, can be used in hospital waste management. In addition, strains with a tolerance of 10 % of NaCl can improve plant growth in the saline affected area.
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Affiliation(s)
- Ritu Singh
- Department of Botany, Sunbeam Women’s College Varuna, Varanasi 221002, India;
- Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi 221005, India; (K.D.P.); (S.K.S.)
| | - Kapil Deo Pandey
- Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi 221005, India; (K.D.P.); (S.K.S.)
| | - Monika Singh
- Department of Biotechnology, School of Life Sciences, Uttaranchal University, Dehradun 248007, India;
| | - Sandeep Kumar Singh
- Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi 221005, India; (K.D.P.); (S.K.S.)
| | - Abeer Hashem
- Botany and Microbiology Department, College of Science, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia; (A.H.); (A.-B.F.A.-A.)
| | - Al-Bandari Fahad Al-Arjani
- Botany and Microbiology Department, College of Science, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia; (A.H.); (A.-B.F.A.-A.)
| | - Elsayed Fathi Abd_Allah
- Plant Production Department, College of Food and Agricultural Sciences, King Saud University, P.O. Box 2460, Riyadh 11451, Saudi Arabia;
| | - Prashant Kumar Singh
- Department of Biotechnology, Pachhunga University College Campus, Mizoram University, Aizawl 796001, India;
| | - Ajay Kumar
- Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi 221005, India; (K.D.P.); (S.K.S.)
- Correspondence: ; Tel.:+91-896-063-9724
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21
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Examining the Effects of the Nitrogen Environment on Growth and N 2-Fixation of Endophytic Herbaspirillum seropedicae in Maize Seedlings by Applying 11C Radiotracing. Microorganisms 2021; 9:microorganisms9081582. [PMID: 34442661 PMCID: PMC8401641 DOI: 10.3390/microorganisms9081582] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 07/15/2021] [Accepted: 07/23/2021] [Indexed: 11/17/2022] Open
Abstract
Herbaspirillum seropedicae, as an endophyte and prolific root colonizer of numerous cereal crops, occupies an important ecological niche in agriculture because of its ability to promote plant growth and potentially improve crop yield. More importantly, there exists the untapped potential to harness its ability, as a diazotroph, to fix atmospheric N2 as an alternative nitrogen resource to synthetic fertilizers. While mechanisms for plant growth promotion remain controversial, especially in cereal crops, one irrefutable fact is these microorganisms rely heavily on plant-borne carbon as their main energy source in support of their own growth and biological functions. Biological nitrogen fixation (BNF), a microbial function that is reliant on nitrogenase enzyme activity, is extremely sensitive to the localized nitrogen environment of the microorganism. However, whether internal root colonization can serve to shield the microorganisms and de-sensitize nitrogenase activity to changes in the soil nitrogen status remains unanswered. We used RAM10, a GFP-reporting strain of H. seropedicae, and administered radioactive 11CO2 tracer to intact 3-week-old maize leaves and followed 11C-photosynthates to sites within intact roots where actively fluorescing microbial colonies assimilated the tracer. We examined the influence of administering either 1 mM or 10 mM nitrate during plant growth on microbial demands for plant-borne 11C. Nitrogenase activity was also examined under the same growth conditions using the acetylene reduction assay. We found that plant growth under low nitrate resulted in higher nitrogenase activity as well as higher microbial demands for plant-borne carbon than plant growth under high nitrate. However, carbon availability was significantly diminished under low nitrate growth due to reduced host CO2 fixation and reduced allocation of carbon resources to the roots. This response of the host caused significant inhibition of microbial growth. In summary, internal root colonization did little to shield these endophytic microorganisms from the nitrogen environment.
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22
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Housh AB, Benoit M, Wilder SL, Scott S, Powell G, Schueller MJ, Ferrieri RA. Plant-Growth-Promoting Bacteria Can Impact Zinc Uptake in Zea mays: An Examination of the Mechanisms of Action Using Functional Mutants of Azospirillum brasilense. Microorganisms 2021; 9:microorganisms9051002. [PMID: 34066521 PMCID: PMC8148439 DOI: 10.3390/microorganisms9051002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 04/27/2021] [Accepted: 05/04/2021] [Indexed: 11/16/2022] Open
Abstract
Among the PGPB, the genus Azospirillum-with an emphasis on A. brasilense-is likely the most studied microorganism for mitigation of plant stress. Here, we report the investigation of functional mutants HM053, ipdC and FP10 of A. brasilense to understand how the biological functions of these microorganisms can affect host Zn uptake. HM053 is a Nif+ constitutively expressed strain that hyper-fixes N2 and produces high levels of the plant's relevant hormone auxin. FP10 is a Nif- strain deficient in N2-fixation. ipdC is a strain that is deficient in auxin production but fixes N2. Zn uptake was measured in laboratory-based studies of 3-week-old plants using radioactive 65Zn2+ (t½ 244 days). Principal Component Analysis was applied to draw out correlations between microbial functions and host 65Zn2+ accumulation. Additionally, statistical correlations were made to our prior data on plant uptake of radioactive 59Fe3+ and 59Fe2+. These correlations showed that low microbial auxin-producing capacity resulted in the greatest accumulation of 65Zn. Just the opposite effect was noted for 59Fe where high microbial auxin-producing capacity resulted in the greatest accumulation of that tracer.
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Affiliation(s)
- Alexandra Bauer Housh
- Missouri Research Reactor Center, University of Missouri, Columbia, MO 65211, USA; (A.B.H.); (S.L.W.); (S.S.); (G.P.); (M.J.S.)
- Chemistry Department, University of Missouri, Columbia, MO 652101, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, MO 65211, USA
| | - Mary Benoit
- Division of Plant Sciences, University of Missouri, Columbia, MO 65211, USA;
| | - Stacy L. Wilder
- Missouri Research Reactor Center, University of Missouri, Columbia, MO 65211, USA; (A.B.H.); (S.L.W.); (S.S.); (G.P.); (M.J.S.)
| | - Stephanie Scott
- Missouri Research Reactor Center, University of Missouri, Columbia, MO 65211, USA; (A.B.H.); (S.L.W.); (S.S.); (G.P.); (M.J.S.)
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA
| | - Garren Powell
- Missouri Research Reactor Center, University of Missouri, Columbia, MO 65211, USA; (A.B.H.); (S.L.W.); (S.S.); (G.P.); (M.J.S.)
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA
| | - Michael J. Schueller
- Missouri Research Reactor Center, University of Missouri, Columbia, MO 65211, USA; (A.B.H.); (S.L.W.); (S.S.); (G.P.); (M.J.S.)
- Chemistry Department, University of Missouri, Columbia, MO 652101, USA
| | - Richard A. Ferrieri
- Missouri Research Reactor Center, University of Missouri, Columbia, MO 65211, USA; (A.B.H.); (S.L.W.); (S.S.); (G.P.); (M.J.S.)
- Chemistry Department, University of Missouri, Columbia, MO 652101, USA
- Interdisciplinary Plant Group, University of Missouri, Columbia, MO 65211, USA
- Division of Plant Sciences, University of Missouri, Columbia, MO 65211, USA;
- Correspondence: ; Tel.: +1-573-882-5211
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23
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Koebnik R, Burokiene D, Bragard C, Chang C, Saux MFL, Kölliker R, Lang JM, Leach JE, Luna EK, Portier P, Sagia A, Ziegle J, Cohen SP, Jacobs JM. The Complete Genome Sequence of Xanthomonas theicola, the Causal Agent of Canker on Tea Plants, Reveals Novel Secretion Systems in Clade-1 Xanthomonads. PHYTOPATHOLOGY 2021; 111:611-616. [PMID: 32997607 DOI: 10.1094/phyto-07-20-0273-sc] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Xanthomonas theicola is the causal agent of bacterial canker on tea plants. There is no complete genome sequence available for X. theicola, a close relative of the species X. translucens and X. hyacinthi, thus limiting basic research for this group of pathogens. Here, we release a high-quality complete genome sequence for the X. theicola type strain, CFBP 4691T. Single-molecule real-time sequencing with a mean coverage of 264× revealed two contigs of 4,744,641 bp (chromosome) and 40,955 bp (plasmid) in size. Genome mining revealed the presence of nonribosomal peptide synthases, two CRISPR systems, the Xps type 2 secretion system, and the Hrp type 3 secretion system. Surprisingly, this strain encodes an additional type 2 secretion system and a novel type 3 secretion system with enigmatic function, hitherto undescribed for xanthomonads. Four type 3 effector genes were found on complete or partial transposons, suggesting a role of transposons in effector gene evolution and spread. This genome sequence fills an important gap to better understand the biology and evolution of the early-branching xanthomonads, also known as clade-1 xanthomonads.
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Affiliation(s)
- Ralf Koebnik
- IRD, Cirad, Université Montpellier, IPME, Montpellier, France
| | - Daiva Burokiene
- Nature Research Centre, Institute of Botany, Laboratory of Plant Pathology, Akademijos g. 2, Vilnius, Lithuania
| | - Claude Bragard
- Earth & Life Institute, Université Catholique Louvain-la-Neuve, Louvain-la-Neuve, Belgium
| | | | - Marion Fischer-Le Saux
- IRHS-UMR 1345, Université d'Angers, INRAE, Institut Agro, SFR 4207 QuaSaV, 49071, CIRM-CFBP, Beaucouzé, France
| | - Roland Kölliker
- Molecular Plant Breeding, Institute of Agricultural Sciences, ETH Zürich, Universitätstrasse 2, 8092 Zürich, Switzerland
| | - Jillian M Lang
- Department of Agricultural Biology, Colorado State University, Fort Collins, CO 80523, U.S.A
| | - Jan E Leach
- Department of Agricultural Biology, Colorado State University, Fort Collins, CO 80523, U.S.A
| | - Emily K Luna
- Department of Agricultural Biology, Colorado State University, Fort Collins, CO 80523, U.S.A
| | - Perrine Portier
- IRHS-UMR 1345, Université d'Angers, INRAE, Institut Agro, SFR 4207 QuaSaV, 49071, CIRM-CFBP, Beaucouzé, France
| | - Angeliki Sagia
- IRD, Cirad, Université Montpellier, IPME, Montpellier, France
- Department of Biology, University of Crete, Heraklion, Greece
| | - Janet Ziegle
- Pacific Biosciences, Menlo Park, CA 94025, U.S.A
| | - Stephen P Cohen
- Department of Plant Pathology, The Ohio State University, Columbus, OH 43210, U.S.A
| | - Jonathan M Jacobs
- Department of Plant Pathology, The Ohio State University, Columbus, OH 43210, U.S.A
- Infectious Disease Institute, The Ohio State University, Columbus, OH 43210, U.S.A
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Fernández-Llamosas H, Díaz E, Carmona M. Motility, Adhesion and c-di-GMP Influence the Endophytic Colonization of Rice by Azoarcus sp. CIB. Microorganisms 2021; 9:microorganisms9030554. [PMID: 33800326 PMCID: PMC7998248 DOI: 10.3390/microorganisms9030554] [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: 02/02/2021] [Revised: 02/18/2021] [Accepted: 03/05/2021] [Indexed: 01/26/2023] Open
Abstract
Proficient crop production is needed to ensure the feeding of a growing global population. The association of bacteria with plants plays an important role in the health state of the plants contributing to the increase of agricultural production. Endophytic bacteria are ubiquitous in most plant species providing, in most cases, plant promotion properties. However, the knowledge on the genetic determinants involved in the colonization of plants by endophytic bacteria is still poorly understood. In this work we have used a genetic approach based on the construction of fliM, pilX and eps knockout mutants to show that the motility mediated by a functional flagellum and the pili type IV, and the adhesion modulated by exopolysaccarides are required for the efficient colonization of rice roots by the endophyte Azoarcus sp. CIB. Moreover, we have demonstrated that expression of an exogenous diguanylate cyclase or phophodiesterase, which causes either an increase or decrease of the intracellular levels of the second messenger cyclic di-GMP (c-di-GMP), respectively, leads to a reduction of the ability of Azoarcus sp. CIB to colonize rice plants. Here we present results demonstrating the unprecedented role of the universal second messenger cyclic-di-GMP in plant colonization by an endophytic bacterium, Azoarcus sp. CIB. These studies pave the way to further strategies to modulate the interaction of endophytes with their target plant hosts.
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Li Y, Li Q, Chen S. Diazotroph Paenibacillus triticisoli BJ-18 Drives the Variation in Bacterial, Diazotrophic and Fungal Communities in the Rhizosphere and Root/Shoot Endosphere of Maize. Int J Mol Sci 2021; 22:1460. [PMID: 33540521 PMCID: PMC7867140 DOI: 10.3390/ijms22031460] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 12/28/2022] Open
Abstract
Application of diazotrophs (N2-fixing microorganisms) can decrease the overuse of nitrogen (N) fertilizer. Until now, there are few studies on the effects of diazotroph application on microbial communities of major crops. In this study, the diazotrophic and endospore-forming Paenibacillus triticisoli BJ-18 was inoculated into maize soils containing different N levels. The effects of inoculation on the composition and abundance of the bacterial, diazotrophic and fungal communities in the rhizosphere and root/shoot endosphere of maize were evaluated by sequencing the 16S rRNA, nifH gene and ITS (Inter Transcribed Spacer) region. P. triticisoli BJ-18 survived and propagated in all the compartments of the maize rhizosphere, root and shoot. The abundances and diversities of the bacterial and diazotrophic communities in the rhizosphere were significantly higher than in both root and shoot endospheres. Each compartment of the rhizosphere, root and shoot had its specific bacterial and diazotrophic communities. Our results showed that inoculation reshaped the structures of the bacterial, diazotrophic and fungal communities in the maize rhizosphere and endosphere. Inoculation reduced the interactions of the bacteria and diazotrophs in the rhizosphere and endosphere, while it increased the fungal interactions. After inoculation, the abundances of Pseudomonas, Bacillus and Paenibacillus in all three compartments, Klebsiella in the rhizosphere and Paenibacillus in the root and shoot were significantly increased, while the abundances of Fusarium and Giberella were greatly reduced. Paenibacillus was significantly correlated with plant dry weight, nitrogenase, N2-fixing rate, P solubilization and other properties of the soil and plant.
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Affiliation(s)
| | | | - Sanfeng Chen
- State Key Laboratory for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing 100094, China; (Y.L.); (Q.L.)
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Burragoni SG, Jeon J. Applications of endophytic microbes in agriculture, biotechnology, medicine, and beyond. Microbiol Res 2021; 245:126691. [PMID: 33508761 DOI: 10.1016/j.micres.2020.126691] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 12/14/2020] [Accepted: 12/30/2020] [Indexed: 12/26/2022]
Abstract
Endophytes are emerging as integral components of plant microbiomes. Some of them play pivotal roles in plant development and plant responses to pathogens and abiotic stresses, whereas others produce useful and/or interesting secondary metabolites. The appreciation of their abilities to affect plant phenotypes and produce useful compounds via genetic and molecular interactions has paved the way for these abilities to be exploited for health and welfare of plants, humans and ecosystems. Here we comprehensively review current and potential applications of endophytes in the agricultural, pharmaceutical, and industrial sectors. In addition, we briefly discuss the research objectives that should be focused upon in the coming years in order for endophytes and their metabolites to be fully harnessed for potential use in diverse areas.
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Affiliation(s)
- Sravanthi Goud Burragoni
- Department of Biotechnology, College of Life and Applied Sciences, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, Republic of Korea.
| | - Junhyun Jeon
- Department of Biotechnology, College of Life and Applied Sciences, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, Republic of Korea.
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Padukkage D, Geekiyanage S, Reparaz JM, Bezus R, Balatti PA, Degrassi G. Bradyrhizobium japonicum, B. elkanii and B. diazoefficiens Interact with Rice (Oryza sativa), Promote Growth and Increase Yield. Curr Microbiol 2020; 78:417-428. [PMID: 33083897 DOI: 10.1007/s00284-020-02249-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 10/09/2020] [Indexed: 10/23/2022]
Abstract
Bradyrhizobium is a genus of plant growth-promoting rhizobacteria (PGPR) that have been studied for several decades mainly for the ability to fix diazotrophic nitrogen after having been established endosymbiotically inside root nodules of the legumes of Fabaceae. The aim of this work was to evaluate the capability of Bradyrhizobium to promote the growth of crops belonging to other families, in this case, rice (Oryza sativa), both in laboratory and in field trials. For laboratory test, surface-sterilized rice seeds were soaked with cultures of each strain and planted in pots. Plant length and dry weight were measured after 35 days. For the field test, rice seeds of varieties Yeruá La Plata and Gurí INTA were inoculated with the three best strains observed in the laboratory test and planted in plots. After 60 days of growth, plant length and dry weight were measured. At harvest time, we measured the dry weight of the aerial part, yield and thousand-grain weight. Inoculation with any of the three species described provoked significant increments compared to the uninoculated control at least in one of the parameters measured, both in the laboratory and in the field tests. Bradyrhizobium japonicum E109 was the strain that promoted rice growth the most in the lab while Bradyrhizobium elkanii SEMIA 587 was the strain that promoted rice growth the most in the field, with increments in yield of approximately 1000 kg/ha. Data obtained suggest that the Bradyrhizobium species promoted all rice growth and yield.
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Affiliation(s)
| | | | - Juan M Reparaz
- Centro de Investigaciones de Fitopatologia (CIDEFI), Facultad de Ciencias Agrarias Y Forestales, Universidad Nacional de La Plata (FCAyF), Comisión de Investigaciones Científicas de La Provincia de Buenos Aires, Buenos Aires, Argentina
| | - Rodolfo Bezus
- Centro de Investigaciones de Fitopatologia (CIDEFI), Facultad de Ciencias Agrarias Y Forestales, Universidad Nacional de La Plata (FCAyF), Comisión de Investigaciones Científicas de La Provincia de Buenos Aires, Buenos Aires, Argentina
| | - Pedro A Balatti
- Centro de Investigaciones de Fitopatologia (CIDEFI), Facultad de Ciencias Agrarias Y Forestales, Universidad Nacional de La Plata (FCAyF), Comisión de Investigaciones Científicas de La Provincia de Buenos Aires, Buenos Aires, Argentina
| | - Giuliano Degrassi
- International Centre for Genetic Engineering and Biotechnology, ICGEB, Buenos Aires, Argentina.
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Groover W, Held D, Lawrence K, Carson K. Plant growth-promoting rhizobacteria: a novel management strategy for Meloidogyne incognita on turfgrass. PEST MANAGEMENT SCIENCE 2020; 76:3127-3138. [PMID: 32309906 DOI: 10.1002/ps.5867] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 04/10/2020] [Accepted: 04/20/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Meloidogyne spp., root-knot nematodes, are among the most economically important plant-parasitic nematodes in turfgrass in the United States. Only a few nematicides are available or efficacious for plant-parasitic nematodes in turfgrass in the United States, and recent work has demonstrated the potential for microbial control of root-knot nematodes in field crops. The objectives of this study were to evaluate the efficacy of 104 plant growth-promoting rhizobacteria (PGPR) strains isolated from grasses in Alabama against M. incognita in vitro, and their ability to manage plant-parasitic nematodes in the glasshouse and microplot settings. RESULTS In vitro mortality ranged from 0.9% to 94.6% by all PGPR strains screened. Ten individual PGPR strains and one three-strain blend (a total of 13 PGPR strains) were advanced to glasshouse and microplot screening. In the glasshouse, six of the 11 PGPR treatments significantly reduced M. incognita population density, with a few strains also promoting some root growth. In the microplot, five of the 11 PGPR treatments significantly reduced M. incognita population density. CONCLUSION Of these strains, 11 were identified as Bacillus spp., one as Stenotrophomonas rhizophila and one as Paenibacillus sonchi. Eight of these strains also were found to have nitrogenase activity, and seven had the ability to produce siderophores, showing a potential mechanism for growth promotion. Overall, results indicate that multiple strains of Bacillus spp. and one strain of S. rhizophila have the potential to reduce M. incognita population density and enhance turfgrass root growth. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Will Groover
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - David Held
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Kathy Lawrence
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Kendra Carson
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
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Papik J, Folkmanova M, Polivkova-Majorova M, Suman J, Uhlik O. The invisible life inside plants: Deciphering the riddles of endophytic bacterial diversity. Biotechnol Adv 2020; 44:107614. [PMID: 32858117 DOI: 10.1016/j.biotechadv.2020.107614] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 07/14/2020] [Accepted: 08/15/2020] [Indexed: 10/25/2022]
Abstract
Endophytic bacteria often promote plant growth and protect their host plant against pathogens, herbivores, and abiotic stresses including drought, increased salinity or pollution. Current agricultural practices are being challenged in terms of climate change and the ever-increasing demand for food. Therefore, the rational exploitation of bacterial endophytes to increase the productivity and resistance of crops appears to be very promising. However, the efficient and larger-scale use of bacterial endophytes for more effective and sustainable agriculture is hindered by very little knowledge on molecular aspects of plant-endophyte interactions and mechanisms driving bacterial communities in planta. In addition, since most of the information on bacterial endophytes has been obtained through culture-dependent techniques, endophytic bacterial diversity and its full biotechnological potential still remain highly unexplored. In this study, we discuss the diversity and role of endophytic populations as well as complex interactions that the endophytes have with the plant and vice versa, including the interactions leading to plant colonization. A description of biotic and abiotic factors influencing endophytic bacterial communities is provided, along with a summary of different methodologies suitable for determining the diversity of bacterial endophytes, mechanisms governing the assembly and structure of bacterial communities in the endosphere, and potential biotechnological applications of endophytes in the future.
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Affiliation(s)
- Jakub Papik
- University of Chemistry and Technology, Prague, Faculty of Food and Biochemical Technology, Department of Biochemistry and Microbiology, Prague, Czech Republic
| | - Magdalena Folkmanova
- University of Chemistry and Technology, Prague, Faculty of Food and Biochemical Technology, Department of Biochemistry and Microbiology, Prague, Czech Republic
| | - Marketa Polivkova-Majorova
- University of Chemistry and Technology, Prague, Faculty of Food and Biochemical Technology, Department of Biochemistry and Microbiology, Prague, Czech Republic
| | - Jachym Suman
- University of Chemistry and Technology, Prague, Faculty of Food and Biochemical Technology, Department of Biochemistry and Microbiology, Prague, Czech Republic
| | - Ondrej Uhlik
- University of Chemistry and Technology, Prague, Faculty of Food and Biochemical Technology, Department of Biochemistry and Microbiology, Prague, Czech Republic.
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Bünger W, Jiang X, Müller J, Hurek T, Reinhold-Hurek B. Novel cultivated endophytic Verrucomicrobia reveal deep-rooting traits of bacteria to associate with plants. Sci Rep 2020; 10:8692. [PMID: 32457320 PMCID: PMC7251102 DOI: 10.1038/s41598-020-65277-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Accepted: 04/30/2020] [Indexed: 02/01/2023] Open
Abstract
Despite the relevance of complex root microbial communities for plant health, growth and productivity, the molecular basis of these plant-microbe interactions is not well understood. Verrucomicrobia are cosmopolitans in the rhizosphere, nevertheless their adaptations and functions are enigmatic since the proportion of cultured members is low. Here we report four cultivated Verrucomicrobia isolated from rice, putatively representing four novel species, and a novel subdivision. The aerobic strains were isolated from roots or rhizomes of Oryza sativa and O. longistaminata. Two of them are the first cultivated endophytes of Verrucomicrobia, as validated by confocal laser scanning microscopy inside rice roots after re-infection under sterile conditions. This extended known verrucomicrobial niche spaces. Two strains were promoting root growth of rice. Discovery of root compartment-specific Verrucomicrobia permitted an across-phylum comparison of the genomic conformance to life in soil, rhizoplane or inside roots. Genome-wide protein domain comparison with niche-specific reference bacteria from distant phyla revealed signature protein domains which differentiated lifestyles in these microhabitats. Our study enabled us to shed light into the dark microbial matter of root Verrucomicrobia, to define genetic drivers for niche adaptation of bacteria to plant roots, and provides cultured strains for revealing causal relationships in plant-microbe interactions by reductionist approaches.
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Affiliation(s)
- Wiebke Bünger
- Department of Microbe-Plant Interactions, University of Bremen, Bremen, Germany
| | - Xun Jiang
- Department of Microbe-Plant Interactions, University of Bremen, Bremen, Germany
| | - Jana Müller
- Department of Microbe-Plant Interactions, University of Bremen, Bremen, Germany.,Department of Botany, University of Bremen, Bremen, Germany
| | - Thomas Hurek
- Department of Microbe-Plant Interactions, University of Bremen, Bremen, Germany
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31
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Quantifying Plant-Borne Carbon Assimilation by Root-Associating Bacteria. Microorganisms 2020; 8:microorganisms8050700. [PMID: 32397579 PMCID: PMC7285072 DOI: 10.3390/microorganisms8050700] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 05/06/2020] [Accepted: 05/08/2020] [Indexed: 11/17/2022] Open
Abstract
Herbaspirillum seropedicae is a rhizobacteria that occupies a specialized ecological niche in agriculture. As an endophyte and prolific grass root colonizer it has the potential to promote plant growth, enhancing crop yield in many cereal crops. While the mechanisms for plant growth promotion are controversial, the one irrefutable fact is these microorganisms rely heavily on plant-borne carbon as their main energy source in support of their biological functions. Unfortunately, the tools and technology enabling researchers to trace carbon exchange between plants and the microorganisms associating with them has been limiting. Here, we demonstrate that radioactive 11CO2 administered to intact maize leaves with translocation of 11C-photosynthates to roots can provide a ‘traceable’ source of carbon whose assimilation by microbial organisms can be quantified with enormous sensitivity. Fluorescence root imaging of RAM10, a green fluorescent protein (GFP) reporting strain of H. seropedicae, was used to identify regions of high microbial colonization. Microbes were mechanically removed from these regions via sonication in saline solution and extracts were subjected to fluorescence measurement and gamma counting to correlate carbon-11 atoms with numbers of colony forming units. The method has potential to translate to other microorganisms provided they possess an optical reporting trait.
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32
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Mosquito S, Bertani I, Licastro D, Compant S, Myers MP, Hinarejos E, Levy A, Venturi V. In Planta Colonization and Role of T6SS in Two Rice Kosakonia Endophytes. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2020; 33:349-363. [PMID: 31609645 DOI: 10.1094/mpmi-09-19-0256-r] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Endophytes live inside plants and are often beneficial. Kosakonia is a novel bacterial genus that includes many diazotrophic plant-associated isolates. Plant-bacteria studies on two rice endophytic Kosakonia beneficial strains were performed, including comparative genomics, secretome profiling, in planta tests, and a field release trial. The strains are efficient rhizoplane and root endosphere colonizers and localized in the root cortex. Secretomics revealed 144 putative secreted proteins, including type VI secretory system (T6SS) proteins. A Kosakonia T6SS genomic knock-out mutant showed a significant decrease in rhizoplane and endosphere colonization ability. A field trial using rice seed inoculated with Kosakonia spp. showed no effect on plant growth promotion upon nitrogen stress and microbiome studies revealed that Kosakonia spp. were significantly more present in the inoculated rice. Comparative genomics indicated that several protein domains were enriched in plant-associated Kosakonia spp. This study highlights that Kosakonia is an important, recently classified genus involved in plant-bacteria interaction.
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Affiliation(s)
- Susan Mosquito
- International Centre for Genetic Engineering and Biotechnology, 34149 Trieste, Italy
| | - Iris Bertani
- International Centre for Genetic Engineering and Biotechnology, 34149 Trieste, Italy
| | - Danilo Licastro
- CBM S.c.r.l., Area Science Park-Basovizza, 34149 Trieste, Italy
| | - Stéphane Compant
- Bioresources Unit, Center for Health & Bioresources, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Vienna, Austria
| | - Michael P Myers
- International Centre for Genetic Engineering and Biotechnology, 34149 Trieste, Italy
| | | | - Asaf Levy
- Department of Plant Pathology and Microbiology, The Robert H. Smith Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Vittorio Venturi
- International Centre for Genetic Engineering and Biotechnology, 34149 Trieste, Italy
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Agtuca BJ, Stopka SA, Tuleski TR, do Amaral FP, Evans S, Liu Y, Xu D, Monteiro RA, Koppenaal DW, Paša-Tolić L, Anderton CR, Vertes A, Stacey G. In-Situ Metabolomic Analysis of Setaria viridis Roots Colonized by Beneficial Endophytic Bacteria. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2020; 33:272-283. [PMID: 31544655 DOI: 10.1094/mpmi-06-19-0174-r] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Over the past decades, crop yields have risen in parallel with increasing use of fossil fuel-derived nitrogen (N) fertilizers but with concomitant negative impacts on climate and water resources. There is a need for more sustainable agricultural practices, and biological nitrogen fixation (BNF) could be part of the solution. A variety of nitrogen-fixing, epiphytic, and endophytic plant growth-promoting bacteria (PGPB) are known to stimulate plant growth. However, compared with the rhizobium-legume symbiosis, little mechanistic information is available as to how PGPB affect plant metabolism. Therefore, we investigated the metabolic changes in roots of the model grass species Setaria viridis upon endophytic colonization by Herbaspirillum seropedicae SmR1 (fix+) or a fix- mutant strain (SmR54) compared with uninoculated roots. Endophytic colonization of the root is highly localized and, hence, analysis of whole-root segments dilutes the metabolic signature of those few cells impacted by the bacteria. Therefore, we utilized in-situ laser ablation electrospray ionization mass spectrometry to sample only those root segments at or adjacent to the sites of bacterial colonization. Metabolites involved in purine, zeatin, and riboflavin pathways were significantly more abundant in inoculated plants, while metabolites indicative of nitrogen, starch, and sucrose metabolism were reduced in roots inoculated with the fix- strain or uninoculated, presumably due to N limitation. Interestingly, compounds, involved in indole-alkaloid biosynthesis were more abundant in the roots colonized by the fix- strain, perhaps reflecting a plant defense response.
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Affiliation(s)
- Beverly J Agtuca
- Divisions of Plant Sciences and Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, U.S.A
| | - Sylwia A Stopka
- Department of Chemistry, The George Washington University, Washington, DC 20052, U.S.A
| | - Thalita R Tuleski
- Divisions of Plant Sciences and Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, U.S.A
- Department of Biochemistry and Molecular Biology, Federal University of Paraná, CP 19046, 81.531-990 Curitiba, PR, Brazil
| | - Fernanda P do Amaral
- Divisions of Plant Sciences and Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, U.S.A
| | - Sterling Evans
- Divisions of Plant Sciences and Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, U.S.A
| | - Yang Liu
- Department of Electrical Engineering and Computer Science, Informatics Institute and Christopher S. Bond Life Sciences Center, University of Missouri Columbia
| | - Dong Xu
- Department of Electrical Engineering and Computer Science, Informatics Institute and Christopher S. Bond Life Sciences Center, University of Missouri Columbia
| | - Rose Adele Monteiro
- Department of Biochemistry and Molecular Biology, Federal University of Paraná, CP 19046, 81.531-990 Curitiba, PR, Brazil
| | - David W Koppenaal
- Environmental Molecular Sciences Laboratory, Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, WA 99354, U.S.A
| | - Ljiljana Paša-Tolić
- Environmental Molecular Sciences Laboratory, Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, WA 99354, U.S.A
| | - Christopher R Anderton
- Environmental Molecular Sciences Laboratory, Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, WA 99354, U.S.A
| | - Akos Vertes
- Department of Chemistry, The George Washington University, Washington, DC 20052, U.S.A
| | - Gary Stacey
- Divisions of Plant Sciences and Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, U.S.A
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Chen X, Marszałkowska M, Reinhold-Hurek B. Jasmonic Acid, Not Salicyclic Acid Restricts Endophytic Root Colonization of Rice. FRONTIERS IN PLANT SCIENCE 2020; 10:1758. [PMID: 32063914 PMCID: PMC7000620 DOI: 10.3389/fpls.2019.01758] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 12/16/2019] [Indexed: 05/20/2023]
Abstract
Research on the interaction between the non-nodule-forming bacterial endophytes and their host plants is still in its infancy. Especially the understanding of plant control mechanisms which govern endophytic colonization is very limited. The current study sets out to determine which hormonal signaling pathway controls endophytic colonization in rice, and whether the mechanisms deviate for a pathogen. The endophyte Azoarcus olearius BH72-rice model was used to investigate root responses to endophytes in comparison to the recently established pathosystem of rice blight Xanthomonas oryzae pv. oryzae PXO99 (Xoo) in flooded roots. In the rice root transcriptome, 523 or 664 genes were found to be differentially expressed in response to Azoarcus or Xoo colonization, respectively; however, the response was drastically different, with only 6% of the differentially expressed genes (DEGs) overlapping. Overall, Xoo infection induced a much stronger defense reaction than Azoarcus colonization, with the latter leading to down-regulation of many defense related DEGs. Endophyte-induced DEGs encoded several enzymes involved in phytoalexin biosynthesis, ROS (reactive oxygen species) production, or pathogenesis-related (PR) proteins. Among putative plant markers related to signal transduction pathways modulated exclusively during Azoarcus colonization, none overlapped with previously published DEGs identified for another rice endophyte, Azospirillum sp. B510. This suggests a large variation in responses of individual genotypic combinations. Interestingly, the DEGs related to jasmonate (JA) signaling pathway were found to be consistently activated by both beneficial endophytes. In contrast, the salicylate (SA) pathway was activated only in roots infected by the pathogen. To determine the impact of SA and JA production on root colonization by the endophyte and the pathogen, rice mutants with altered hormonal responses were employed: mutant cpm2 deficient in jasmonate synthesis, and RNA interference (RNAi) knockdown lines of NPR1 decreased in salicylic acid-mediated defense responses (NPR1-kd). Only in cpm2, endophytic colonization of Azoarcus was significantly increased, while Xoo colonization was not affected. Surprisingly, NPR1-kd lines showed slightly decreased colonization by Xoo, contrary to published results for leaves. These outcomes suggest that JA but not SA signaling is involved in controlling the Azoarcus endophyte density in roots and can restrict internal root colonization, thereby shaping the beneficial root microbiome.
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Affiliation(s)
| | | | - Barbara Reinhold-Hurek
- Department of Microbe-Plant Interactions, Faculty of Biology and Chemistry, CBIB (Center for Biomolecular Interactions Bremen), University of Bremen, Bremen, Germany
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Nag P, Shriti S, Das S. Microbiological strategies for enhancing biological nitrogen fixation in nonlegumes. J Appl Microbiol 2020; 129:186-198. [PMID: 31858682 DOI: 10.1111/jam.14557] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 12/12/2019] [Accepted: 12/16/2019] [Indexed: 01/17/2023]
Abstract
In an agro-ecosystem, industrially produced nitrogenous fertilizers are the principal sources of nitrogen for plant growth; unfortunately these also serve as the leading sources of pollution. Hence, it becomes imperative to find pollution-free methods of providing nitrogen to crop plants. A diverse group of free-living, plant associative and symbiotic prokaryotes are able to perform biological nitrogen fixation (BNF). BNF is a two component process involving the nitrogen fixing diazotrophs and the host plant. Symbiotic nitrogen fixation is most efficient as it can fix nitrogen inside the nodule formed on the roots of the plant; delivering nitrogen directly to the host. However, most of the important crop plants are nonleguminous and are unable to form symbiotic associations. In this context, the plant associative and endophytic diazotrophs assume importance. BNF in nonlegumes can be encouraged either through the transfer of BNF traits from legumes or by elevating the nitrogen fixing capacity of the associative and endophytic diazotrophs. In this review we discuss mainly the microbiological strategies which may be used in nonleguminous crops for enhancement of BNF.
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Affiliation(s)
- P Nag
- Division of Plant Biology, Bose Institute, Kolkata, West Bengal, India
| | - S Shriti
- Division of Plant Biology, Bose Institute, Kolkata, West Bengal, India
| | - S Das
- Division of Plant Biology, Bose Institute, Kolkata, West Bengal, India
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36
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King E, Wallner A, Rimbault I, Barrachina C, Klonowska A, Moulin L, Czernic P. Monitoring of Rice Transcriptional Responses to Contrasted Colonizing Patterns of Phytobeneficial Burkholderia s.l. Reveals a Temporal Shift in JA Systemic Response. FRONTIERS IN PLANT SCIENCE 2019; 10:1141. [PMID: 31608089 PMCID: PMC6769109 DOI: 10.3389/fpls.2019.01141] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 08/21/2019] [Indexed: 05/30/2023]
Abstract
In the context of plant-pathogen and plant-mutualist interactions, the underlying molecular bases associated with host colonization have been extensively studied. However, it is not the case for non-mutualistic beneficial interactions or associative symbiosis with plants. Particularly, little is known about the transcriptional regulations associated with the immune tolerance of plants towards beneficial microbes. In this context, the study of the Burkholderia rice model is very promising to describe the molecular mechanisms involved in associative symbiosis. Indeed, several species of the Burkholderia sensu lato (s.l.) genus can colonize rice tissues and have beneficial effects; particularly, two species have been thoroughly studied: Burkholderia vietnamiensis and Paraburkholderia kururiensis. This study aims to compare the interaction of these species with rice and especially to identify common or specific plant responses. Therefore, we analyzed root colonization of the rice cultivar Nipponbare using DsRed-tagged bacterial strains and produced the transcriptomes of both roots and leaves 7 days after root inoculation. This led us to the identification of a co-expression jasmonic acid (JA)-related network exhibiting opposite regulation in response to the two strains in the leaves of inoculated plants. We then monitored by quantitative polymerase chain reaction (qPCR) the expression of JA-related genes during time course colonization by each strain. Our results reveal a temporal shift in this JA systemic response, which can be related to different colonization strategies of both strains.
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Affiliation(s)
- Eoghan King
- IRD, CIRAD, University of Montpellier, IPME, Montpellier, France
| | - Adrian Wallner
- IRD, CIRAD, University of Montpellier, IPME, Montpellier, France
| | | | - Célia Barrachina
- Montpellier GenomiX (MGX), c/o Institut de Génomique Fonctionnelle, Montpellier, France
| | | | - Lionel Moulin
- IRD, CIRAD, University of Montpellier, IPME, Montpellier, France
| | - Pierre Czernic
- IRD, CIRAD, University of Montpellier, IPME, Montpellier, France
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Li Y, Sun H, Wu Z, Li H, Sun Q. Urban traffic changes the biodiversity, abundance, and activity of phyllospheric nitrogen-fixing bacteria. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:16097-16104. [PMID: 30968298 DOI: 10.1007/s11356-019-05008-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 03/26/2019] [Indexed: 06/09/2023]
Abstract
The phyllosphere provides appropriate conditions for colonization by microorganisms, including diazotrophic bacteria. However, a poor understanding of the effects of the atmospheric environment on the phyllospheric diazotrophic communities persists. We detected the biodiversity, abundance, and activity of nitrogen-fixing bacteria in the phyllospheres of two evergreen shrubs, Nerium indicum Mill. and Osmanthus sp., sampled from urban areas with heavy traffic, a college campus, and a forest. Quantitative PCR analysis indicated that the copy numbers of nifH sequences were highest in the phyllospheres of both plants in heavy-traffic urban areas and correlated with the recorded nitrogenase activities of the phyllospheres. Similarly, the phyllosphere from heavy-traffic urban areas also possessed the highest biodiversity indices of diazotrophic communities from both the two plants. Pyrosequencing analysis revealed a diversity of nifH sequences in phyllosphere that were mostly uniquely found in the phyllosphere, and many of these were proteobacteria-like and cyanobacteria-like. Members of the Proteobacteria, mostly of which were not closely related to unknown organisms, were detected exclusively in the phyllosphere and represented substantial fractions of their associated diazotrophic communities. Our study provides initial insight into the shifts in the biodiversity and community structure of N2-fixing microorganisms in the phyllospheres of different atmospheric environments.
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Affiliation(s)
- Yang Li
- School of Resources and Environmental Engineering, Anhui University, Hefei, China
| | - Hong Sun
- College of Life Science, Northeast Forestry University, Harbin, China
| | - Zhaojun Wu
- School of Resources and Environmental Engineering, Anhui University, Hefei, China
| | - Hui Li
- School of Resources and Environmental Engineering, Anhui University, Hefei, China
| | - Qingye Sun
- School of Resources and Environmental Engineering, Anhui University, Hefei, China.
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Li Y, Li Y, Zhang H, Wang M, Chen S. Diazotrophic Paenibacillus beijingensis BJ-18 Provides Nitrogen for Plant and Promotes Plant Growth, Nitrogen Uptake and Metabolism. Front Microbiol 2019; 10:1119. [PMID: 31191471 PMCID: PMC6548809 DOI: 10.3389/fmicb.2019.01119] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 05/03/2019] [Indexed: 11/29/2022] Open
Abstract
Diazotrophic bacteria can reduce N2 into plant-available ammonium (NH4+), promoting plant growth and reducing nitrogen (N) fertilizer requirements. However, there are few systematic studies on the effects of diazotrophic bacteria on biological N2 fixation (BNF) contribution rate and host plant N uptake and metabolism. In this study, the interactions of the diazotrophic Paenibacillus beijingensis BJ-18 with wheat, maize, and cucumber were investigated when it was inoculated to these plant seedlings grown in both low N and high N soils, with un-inoculated plants as controls. This study showed that GFP-tagged P. beijingensis BJ-18 colonized inside and outside seedlings, forming rhizospheric and endophytic colonies in roots, stems, and leaves. The numbers of this bacterium in the inoculated plants depended on soil N levels. Under low N, inoculation significantly increased shoot dry weight (wheat 86.1%, maize 46.6%, and cucumber 103.6%) and root dry weight (wheat 46.0%, maize 47.5%, and cucumber 20.3%). The 15N-isotope-enrichment experiment indicated that plant seedlings derived 12.9–36.4% N from BNF. The transcript levels of nifH in the inoculated plants were 0.75–1.61 folds higher in low N soil than those in high N soil. Inoculation enhanced NH4+ and nitrate (NO3-) uptake from soil especially under low N. The total N in the inoculated plants were increased by 49.1–92.3% under low N and by 13–15.5% under high N. Inoculation enhanced activities of glutamine synthetase (GS) and nitrate reductase (NR) in plants, especially under low N. The expression levels of N uptake and N metabolism genes: AMT (ammonium transporter), NRT (nitrate transporter), NiR (nitrite reductase), NR, GS and GOGAT (glutamate synthase) in the inoculated plants grown under low N were up-regulated 1.5–91.9 folds, but they were not obviously changed under high N. Taken together, P. beijingensis BJ-18 was an effective, endophytic and diazotrophic bacterium. This bacterium contributed to plants with fixed N2, promoted plant growth and N uptake, and enhanced gene expression and enzyme activities involved in N uptake and assimilation in plants. However, these positive effects on plants were regulated by soil N status. This study might provide insight into the interactions of plants with beneficial associative and endophytic diazotrophic bacteria.
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Affiliation(s)
- Yongbin Li
- State Key Laboratory for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing, China
| | - Yunlong Li
- State Key Laboratory for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing, China
| | - Haowei Zhang
- State Key Laboratory for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing, China
| | - Minyang Wang
- State Key Laboratory for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing, China
| | - Sanfeng Chen
- State Key Laboratory for Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing, China
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Plant beneficial endophytic bacteria: Mechanisms, diversity, host range and genetic determinants. Microbiol Res 2019; 221:36-49. [DOI: 10.1016/j.micres.2019.02.001] [Citation(s) in RCA: 258] [Impact Index Per Article: 51.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 12/11/2018] [Accepted: 02/01/2019] [Indexed: 12/13/2022]
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Inside the plant: addressing bacterial endophytes in biotic stress alleviation. Arch Microbiol 2019; 201:415-429. [PMID: 30834947 DOI: 10.1007/s00203-019-01642-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 11/06/2018] [Accepted: 02/26/2019] [Indexed: 12/28/2022]
Abstract
Bacterial endophytes are the internal association of bacteria with the plants, cherished whole or any part of their life cycle inside the plant. They are reported to improve plant health against the biotic stresses via de novo synthesis of structural compounds and stimulation of plant immunity. They are found to be vital in development of host resistance against phytopathogens and capable in reducing and elimination of deleterious effects of plant pathogens. Fungal-, bacterial-, viral-, insect- and nematode-associated negative effect can be reduced by the bacterial endophytes. They are also reported to control plant pathogens through several defense mechanisms such as by producing antimicrobial compounds and antibiotics, de novo synthesis of structural compounds, keeping out of pathogens by niche competition and induction of plant immunity or induced systemic resistance. In this review, an effort is made to summarize the exploitation of endophytic bacteria as a biological substitute to control biotic stresses in agricultural practices.
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Ke X, Feng S, Wang J, Lu W, Zhang W, Chen M, Lin M. Effect of inoculation with nitrogen-fixing bacterium Pseudomonas stutzeri A1501 on maize plant growth and the microbiome indigenous to the rhizosphere. Syst Appl Microbiol 2018; 42:248-260. [PMID: 30477902 DOI: 10.1016/j.syapm.2018.10.010] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 09/21/2018] [Accepted: 10/31/2018] [Indexed: 12/12/2022]
Abstract
Plant growth promoting diazotrophs with the ability to associate with plant roots are in common use as inoculants to benefit crop yield and to mitigate chemical nitrogen fertilization. However, limited information is available in understanding to what extent the plant growth-promoting effect of the inoculum has on the plant's nitrogen acquisition as well as on the impact of inoculation on the indigenous rhizosphere microbial population. Here we reported on experiments that assessed how endophytic Pseudomonas stutzeri A1501 inoculated on maize improved plant growth and plant nitrogen content using a 15N dilution technique under two water regime conditions. The effects of inoculation and different water regimes were also assessed for the maize rhizospheric and surface soil communities by MiSeq community sequencing combined with qPCR of functional genes and transcripts (nifH and amoA) related to nitrogen cycling. Results support maize inoculated with P. stutzeri A1501 grew better and accumulated more nitrogen with a lower δ15N signature after 60 days than did plants inoculated with nifH-mutant and sterilized A1501 cells (non N2-fixing controls). Inoculant contribution to the plant was estimated to range from 0.30 to 0.82g N/plant, depending on water conditions. Inoculation with P. stutzeri A1501 significantly altered the composition of the diazotrophic community that P. stutzeri became dominant in the rhizosphere, and also increased the population of indigenous diazotrophs and ammonia oxidizers and functional genes transcripts. Redundancy analysis revealed that soil compartment and A1501 inoculation treatments were the main factors affecting the distribution of the diazotrophic community.
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Affiliation(s)
- Xiubin Ke
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Shuai Feng
- Life Science and Engineering College, Southwest University of Science and Technology, Mianyang 621010, Sichuan, China
| | - Jin Wang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; Life Science and Engineering College, Southwest University of Science and Technology, Mianyang 621010, Sichuan, China
| | - Wei Lu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Wei Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Ming Chen
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Min Lin
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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Velichko NS, Surkina AK, Fedonenko YP, Zdorovenko EL, Konnova SA. Structural Peculiarities and Biological Properties of the Lipopolysaccharide from Herbaspirillum seropedicae Z78. Microbiology (Reading) 2018. [DOI: 10.1134/s002626171805017x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Chu S, Zhang D, Zhi Y, Wang B, Chi CP, Zhang D, Liu Y, Zhou P. Enhanced removal of nitrate in the maize rhizosphere by plant growth-promoting Bacillus megaterium NCT-2, and its colonization pattern in response to nitrate. CHEMOSPHERE 2018; 208:316-324. [PMID: 29883866 DOI: 10.1016/j.chemosphere.2018.05.189] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 05/14/2018] [Accepted: 05/30/2018] [Indexed: 06/08/2023]
Abstract
High soil nitrate concentrations can lead to the secondary salinization of soils. Bacillus megaterium NCT-2 is a wild-type strain isolated from secondary salinized soil and is very effective in reducing nitrate. Laboratory and greenhouse experiments were carried out to investigate its nitrate reduction capabilities, colonization pattern, and plant growth promotion responses to nitrate content in the soil. B. megaterium NCT-2 was marked with a green fluorescent protein (gfp) gene and was left to successfully colonize maize roots and the rhizosphere. Inoculation with gfp-tagged NCT-2 significantly promoted nitrate removal from the soil and improved plant growth. Confocal microscopy results revealed that NCT-2 is an endophyte that can colonize the meristematic and elongation zones of the root tip, and the middle segment of the root. Soil nitrate concentration had no significant effect on NCT-2 distribution. The gfp-tagged NCT-2 populations in the roots and rhizosphere soil first increased, but then decreased, and at the end of the experiment, colonization levels in the rhizosphere soil stabilized at ∼5 × 104 CFU g-1 soil. However, the levels in the roots increased again to 1-3 × 104 CFU g-1 root in the different treatments. The NCT-2 population in the roots was significantly affected by nitrate content. A nitrate-nitrogen concentration of 72 mg kg-1 was the optimum concentration for NCT-2 colonization of maize roots. This study will improve the agricultural application of NCT-2 as a biofertilizer for nitrate removal and plant growth promotion.
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Affiliation(s)
- Shaohua Chu
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture, Shanghai, China; Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai, China
| | - Dan Zhang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture, Shanghai, China; Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai, China.
| | - Yuee Zhi
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture, Shanghai, China; Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai, China
| | - Bin Wang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture, Shanghai, China; Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai, China
| | - Chin-Ping Chi
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture, Shanghai, China; Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai, China
| | - Dongwei Zhang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture, Shanghai, China; Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai, China
| | - Yang Liu
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture, Shanghai, China; Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai, China
| | - Pei Zhou
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture, Shanghai, China; Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai, China.
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Jha P, Panwar J, Jha PN. Mechanistic insights on plant root colonization by bacterial endophytes: a symbiotic relationship for sustainable agriculture. ACTA ACUST UNITED AC 2018. [DOI: 10.1007/s42398-018-0011-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Coba de la Peña T, Fedorova E, Pueyo JJ, Lucas MM. The Symbiosome: Legume and Rhizobia Co-evolution toward a Nitrogen-Fixing Organelle? FRONTIERS IN PLANT SCIENCE 2018; 8:2229. [PMID: 29403508 PMCID: PMC5786577 DOI: 10.3389/fpls.2017.02229] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 12/19/2017] [Indexed: 05/21/2023]
Abstract
In legume nodules, symbiosomes containing endosymbiotic rhizobial bacteria act as temporary plant organelles that are responsible for nitrogen fixation, these bacteria develop mutual metabolic dependence with the host legume. In most legumes, the rhizobia infect post-mitotic cells that have lost their ability to divide, although in some nodules cells do maintain their mitotic capacity after infection. Here, we review what is currently known about legume symbiosomes from an evolutionary and developmental perspective, and in the context of the different interactions between diazotroph bacteria and eukaryotes. As a result, it can be concluded that the symbiosome possesses organelle-like characteristics due to its metabolic behavior, the composite origin and differentiation of its membrane, the retargeting of host cell proteins, the control of microsymbiont proliferation and differentiation by the host legume, and the cytoskeletal dynamics and symbiosome segregation during the division of rhizobia-infected cells. Different degrees of symbiosome evolution can be defined, specifically in relation to rhizobial infection and to the different types of nodule. Thus, our current understanding of the symbiosome suggests that it might be considered a nitrogen-fixing link in organelle evolution and that the distinct types of legume symbiosomes could represent different evolutionary stages toward the generation of a nitrogen-fixing organelle.
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Affiliation(s)
- Teodoro Coba de la Peña
- Instituto de Ciencias Agrarias ICA-CSIC, Madrid, Spain
- Centro de Estudios Avanzados en Zonas Áridas (CEAZA), La Serena, Chile
| | - Elena Fedorova
- Instituto de Ciencias Agrarias ICA-CSIC, Madrid, Spain
- K. A. Timiryazev Institute of Plant Physiology, Russian Academy of Science, Moscow, Russia
| | - José J Pueyo
- Instituto de Ciencias Agrarias ICA-CSIC, Madrid, Spain
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Griffin EA, Carson WP. Tree Endophytes: Cryptic Drivers of Tropical Forest Diversity. ENDOPHYTES OF FOREST TREES 2018. [DOI: 10.1007/978-3-319-89833-9_4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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47
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Kandel SL, Joubert PM, Doty SL. Bacterial Endophyte Colonization and Distribution within Plants. Microorganisms 2017; 5:E77. [PMID: 29186821 PMCID: PMC5748586 DOI: 10.3390/microorganisms5040077] [Citation(s) in RCA: 233] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 11/21/2017] [Accepted: 11/23/2017] [Indexed: 11/16/2022] Open
Abstract
The plant endosphere contains a diverse group of microbial communities. There is general consensus that these microbial communities make significant contributions to plant health. Both recently adopted genomic approaches and classical microbiology techniques continue to develop the science of plant-microbe interactions. Endophytes are microbial symbionts residing within the plant for the majority of their life cycle without any detrimental impact to the host plant. The use of these natural symbionts offers an opportunity to maximize crop productivity while reducing the environmental impacts of agriculture. Endophytes promote plant growth through nitrogen fixation, phytohormone production, nutrient acquisition, and by conferring tolerance to abiotic and biotic stresses. Colonization by endophytes is crucial for providing these benefits to the host plant. Endophytic colonization refers to the entry, growth and multiplication of endophyte populations within the host plant. Lately, plant microbiome research has gained considerable attention but the mechanism allowing plants to recruit endophytes is largely unknown. This review summarizes currently available knowledge about endophytic colonization by bacteria in various plant species, and specifically discusses the colonization of maize plants by Populus endophytes.
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Affiliation(s)
| | | | - Sharon L. Doty
- School of Environmental and Forest Sciences, College of the Environment, University of Washington, Seattle, WA 98195-2100, USA; (S.L.K.); (P.M.J.)
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48
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Transmission of Bacterial Endophytes. Microorganisms 2017; 5:microorganisms5040070. [PMID: 29125552 PMCID: PMC5748579 DOI: 10.3390/microorganisms5040070] [Citation(s) in RCA: 183] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 11/06/2017] [Accepted: 11/07/2017] [Indexed: 01/02/2023] Open
Abstract
Plants are hosts to complex communities of endophytic bacteria that colonize the interior of both below- and aboveground tissues. Bacteria living inside plant tissues as endophytes can be horizontally acquired from the environment with each new generation, or vertically transmitted from generation to generation via seed. A better understanding of bacterial endophyte transmission routes and modes will benefit studies of plant–endophyte interactions in both agricultural and natural ecosystems. In this review, we provide an overview of the transmission routes that bacteria can take to colonize plants, including vertically via seeds and pollen, and horizontally via soil, atmosphere, and insects. We discuss both well-documented and understudied transmission routes, and identify gaps in our knowledge on how bacteria reach the inside of plants. Where little knowledge is available on endophytes, we draw from studies on bacterial plant pathogens to discuss potential transmission routes. Colonization of roots from soil is the best studied transmission route, and probably the most important, although more studies of transmission to aerial parts and stomatal colonization are needed, as are studies that conclusively confirm vertical transfer. While vertical transfer of bacterial endophytes likely occurs, obligate and strictly vertically transferred symbioses with bacteria are probably unusual in plants. Instead, plants appear to benefit from the ability to respond to a changing environment by acquiring its endophytic microbiome anew with each generation, and over the lifetime of individuals.
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Walitang DI, Kim K, Madhaiyan M, Kim YK, Kang Y, Sa T. Characterizing endophytic competence and plant growth promotion of bacterial endophytes inhabiting the seed endosphere of Rice. BMC Microbiol 2017; 17:209. [PMID: 29073903 PMCID: PMC5658939 DOI: 10.1186/s12866-017-1117-0] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 10/18/2017] [Indexed: 12/20/2022] Open
Abstract
Background Rice (Oryza sativa L. ssp. indica) seeds as plant microbiome present both an opportunity and a challenge to colonizing bacterial community living in close association with plants. Nevertheless, the roles and activities of bacterial endophytes remain largely unexplored and insights into plant-microbe interaction are compounded by its complexity. In this study, putative functions or physiological properties associated with bacterial endophytic nature were assessed. Also, endophytic roles in plant growth and germination that may allow them to be selectively chosen by plants were also studied. Results The cultivable seed endophytes were dominated by Proteobacteria particularly class Gammaproteobacteria. Highly identical type strains were isolated from the seed endosphere regardless of the rice host’s physiological tolerance to salinity. Among the type strains, Flavobacterium sp., Microbacterium sp. and Xanthomonas sp. were isolated from the salt-sensitive and salt-tolerant cultivars. PCA-Biplot ordination also showed that specific type strains isolated from different rice cultivars have distinguishing similar characteristics. Flavobacterium sp. strains are phosphate solubilizers and indole-3-acetic acid producers with high tolerance to salinity and osmotic stress. Pseudomonas strains are characterized as high siderophore producers while Microbacterium sp. and Xanthomonas sp. strains have very high pectinase and cellulase activity. Among the physiological traits of the seed endophytes, bacterial pectinase and cellulase activity are positively correlated as well as salt and osmotic tolerance. Overall characterization shows that majority of the isolates could survive in 4–8% salt concentration as well as in 0.6 M and 1.2 M sucrose solution. The activities of catalase, pectinase and cellulase were also observed in almost all of the isolates indicating the importance of these characteristics for survival and colonization into the seed endosphere. Seed bacterial endophytes also showed promising plant growth promoting activities including hormone modulation, nitrogen fixation, siderophore production and phosphate solubilization. Conclusion Though many of the isolates possess similar PGP and endophytic physiological traits, this study shows some prominent and distinguishing traits among bacterial groups indicating key determinants for their success as endophytes in the rice seed endosphere. Rice seeds are also inhabited by bacterial endophytes that promote growth during early seedling development. Electronic supplementary material The online version of this article (10.1186/s12866-017-1117-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Denver I Walitang
- Department of Environmental and Biological Chemistry, College of Agriculture, Life and Environmental Sciences, Chungbuk National University, Cheongju, Chungbuk, 28644, Republic of Korea
| | - Kiyoon Kim
- Department of Environmental and Biological Chemistry, College of Agriculture, Life and Environmental Sciences, Chungbuk National University, Cheongju, Chungbuk, 28644, Republic of Korea
| | - Munusamy Madhaiyan
- Temasek Life Sciences Laboratory, Biomaterials and Biocatalyst, National University of Singapore, Singapore, Singapore
| | - Young Kee Kim
- Department of Environmental and Biological Chemistry, College of Agriculture, Life and Environmental Sciences, Chungbuk National University, Cheongju, Chungbuk, 28644, Republic of Korea
| | - Yeongyeong Kang
- Department of Environmental and Biological Chemistry, College of Agriculture, Life and Environmental Sciences, Chungbuk National University, Cheongju, Chungbuk, 28644, Republic of Korea
| | - Tongmin Sa
- Department of Environmental and Biological Chemistry, College of Agriculture, Life and Environmental Sciences, Chungbuk National University, Cheongju, Chungbuk, 28644, Republic of Korea.
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Li O, Xiao R, Sun L, Guan C, Kong D, Hu X. Bacterial and diazotrophic diversities of endophytes in Dendrobium catenatum determined through barcoded pyrosequencing. PLoS One 2017; 12:e0184717. [PMID: 28931073 PMCID: PMC5607135 DOI: 10.1371/journal.pone.0184717] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 08/29/2017] [Indexed: 01/22/2023] Open
Abstract
As an epiphyte orchid, Dendrobium catenatum relies on microorganisms for requisite nutrients. Metagenome pyrosequencing based on 16S rRNA and nifH genes was used to characterize the bacterial and diazotrophic communities associated with D. catenatum collected from 5 districts in China. Based on Meta-16S rRNA sequencing, 22 bacterial phyla and 699 genera were identified, distributed as 125 genera from 8 phyla and 319 genera from 10 phyla shared by all the planting bases and all the tissues, respectively. The predominant Proteobacteria varied from 71.81% (GZ) to 96.08% (YN), and Delftia (10.39-38.42%), Burkholderia (2.71-15.98%), Escherichia/Shigella (4.90-25.12%), Pseudomonas (2.68-30.72%) and Sphingomonas (1.83-2.05%) dominated in four planting bases. Pseudomonas (17.94-22.06%), Escherichia/Shigella (6.59-11.59%), Delftia (9.65-22.14%) and Burkholderia (3.12-11.05%) dominated in all the tissues. According to Meta-nifH sequencing, 4 phyla and 45 genera were identified, while 17 genera and 24 genera from 4 phyla were shared by all the planting bases and all the tissues, respectively. Burkholderia and Bradyrhizobium were the most popular in the planting bases, followed by Methylovirgula and Mesorhizobium. Mesorhizobium was the most popular in different tissues, followed by Beijerinckia, Xanthobacter, and Burkholderia. Among the genera, 39 were completely overlapped with the results based on the 16S rRNA gene. In conclusion, abundant bacteria and diazotrophs were identified in common in different tissues of D. catenatum from five planting bases, which might play a great role in the supply of nutrients such as nitrogen. The exact abundance of phylum and genus on the different tissues from different planting bases need deeper sequencing with more samples.
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Affiliation(s)
- Ou Li
- College of Life Science, Zhejiang Sci-Tech University, Xiasha, Hangzhou, PR China
| | - Rong Xiao
- College of Life Science, Zhejiang Sci-Tech University, Xiasha, Hangzhou, PR China
| | - Lihua Sun
- Zhejiang Academy of Medical Sciences, Hangzhou, PR China
| | - Chenglin Guan
- College of Life Science, Zhejiang Sci-Tech University, Xiasha, Hangzhou, PR China
| | - Dedong Kong
- Agricultural Experiment Station, Zhejiang Univesity, Hangzhou, PR China
| | - Xiufang Hu
- College of Life Science, Zhejiang Sci-Tech University, Xiasha, Hangzhou, PR China
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