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Wu Y, Wang H, Peng L, Zhao H, Zhang Q, Tao Q, Tang X, Huang R, Li B, Wang C. Root-soil-microbiome interaction in the rhizosphere of Masson pine (Pinus massoniana) under different levels of heavy metal pollution. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 283:116779. [PMID: 39083870 DOI: 10.1016/j.ecoenv.2024.116779] [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: 05/20/2024] [Revised: 07/05/2024] [Accepted: 07/22/2024] [Indexed: 08/02/2024]
Abstract
Heavy metal pollution of the soil affects the environment and human health. Masson pine is a good candidate for phytoremediation of heavy metal in mining areas. Microorganisms in the rhizosphere can help with the accumulation of heavy metal in host plants. However, studies on its rhizosphere bacterial communities under heavy metal pollution are still limited. Therefore, in this study, the chemical and bacterial characteristics of Masson pine rhizosphere under four different levels of heavy metal pollution were investigated using 16 S rRNA gene sequencing, soil chemistry and analysis of plant enzyme activities. The results showed that soil heavy metal content, plant oxidative stress and microbial diversity damage were lower the farther they were from the mine dump. The co-occurrence network relationship of slightly polluted soils (C1 and C2) was more complicated than that of highly polluted soils (C3 and C4). Relative abundance analysis indicated Sphingomonas and Pseudolabrys were more abundant in slightly polluted soils (C1 and C2), while Gaiella and Haliangium were more abundant in highly polluted soils (C3 and C4). LEfSe analysis indicated Burkholderiaceae, Xanthobacteraceae, Gemmatimonadaceae, Gaiellaceae were significantly enriched in C1 to C4 site, respectively. Mantel analysis showed that available cadmium (Cd) contents of soil was the most important factor influencing the bacterial community assembly. Correlation analysis showed that eight bacterial genus were significantly positively associated with soil available Cd content. To the best of our knowledge, this is the first study to investigate the rhizospheric bacterial community of Masson pine trees under different degrees of heavy metal contamination, which lays the foundation for beneficial bacteria-based phytoremediation using Masson pines in the future.
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Affiliation(s)
- Yingjie Wu
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China.
| | - Haidong Wang
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Lu Peng
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Haiyang Zhao
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Qiannian Zhang
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Qi Tao
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Xiaoyan Tang
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Rong Huang
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Bing Li
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Changquan Wang
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China.
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Yin C, Lei W, Wang S, Xie G, Qiu D. Biochar and arbuscular mycorrhizal fungi promote rapid-cycling Brassica napus growth under cadmium stress. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 953:176034. [PMID: 39236812 DOI: 10.1016/j.scitotenv.2024.176034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2024] [Revised: 09/02/2024] [Accepted: 09/02/2024] [Indexed: 09/07/2024]
Abstract
PURPOSE To explore the mechanisms of tolerance of Brassica napus to ultra-high concentration cadmium pollution and the synergistic effects of biochar (BC) and Arbuscular mycorrhizal fungi (AMF) on plant growth under cadmium (Cd) stress. RESULTS The application of 5 % BC and inoculation with 10 g AMF significantly promoted the growth and development of B. napus. The combined application of BC and AMF (BC1A and BC2A) was better than the single application. At the Cd 200 mg/kg level, BC1A increased the fresh weight and Cd content of the above-ground parts of B. napus by 35.5 % and decreased by 21.20 %. The SOD and POD activities increased by 30.63 % and 73.37 %. The MDA and H2O2 contents decreased by 40.8 % and 69.99 %, soluble sugar content increased by 37.96 %. At the Cd 300 mg/kg level, BC1A increased the fresh weight and Cd content of the above-ground parts of B. napus by 32.8 % and decreased by 15.99 %. The SOD and POD activities increased by 39.06 % and 93.56 %. The MDA and H2O2 contents decreased by 28.39 % and 72.45 %, and the soluble sugar content increased by 21.16 %. Overall, both BC and AMF treatments alone or in combination (BC1A) were able to alleviate Cd stress and promote plant growth, with the combination of biochar and AMF being the most effective. Furthermore, transcriptome analyses indicated that BC may improve cadmium resistance in B. napus by significantly up-regulating the expression of genes related to peroxidase, photosynthesis, and plant MAPK signaling pathways. AMF may alleviate the toxicity of Cd stress on B. napus by up-regulating the expression of genes related to peroxisomes, phytohormone signaling, and carotenoid biosynthesis. The results of the study will provide support for ecological restoration technology in extremely heavy metal-polluted environments and provide some reference for the application and popularization of BC and AMF conjugation technology.
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Affiliation(s)
- Chunru Yin
- Center of Space Exploration, Ministry of Education, Chongqing University, Chongqing 400044, China; School of Life Sciences, Chongqing University, Chongqing 401331, China; Chongqing Research Institute of NCU, Chongqing 402660, China
| | - Weixia Lei
- Crop Institute, Anhui Academy of Agricultural Sciences, Hefei 230031, China
| | - Sijie Wang
- Center of Space Exploration, Ministry of Education, Chongqing University, Chongqing 400044, China; School of Life Sciences, Chongqing University, Chongqing 401331, China; Chongqing Research Institute of NCU, Chongqing 402660, China
| | - Gengxin Xie
- Center of Space Exploration, Ministry of Education, Chongqing University, Chongqing 400044, China; Chongqing Research Institute of NCU, Chongqing 402660, China; Urban Construction and Environmental Engineering, Chongqing University, Chongqing 400044, China.
| | - Dan Qiu
- Center of Space Exploration, Ministry of Education, Chongqing University, Chongqing 400044, China; School of Life Sciences, Chongqing University, Chongqing 401331, China; Chongqing Research Institute of NCU, Chongqing 402660, China.
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Wang Q, Zhou Q, Feng Y, Yang X. Foliar application protected vegetable against poisonous element cadmium and mitigated human health risks. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:171915. [PMID: 38522551 DOI: 10.1016/j.scitotenv.2024.171915] [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: 12/18/2023] [Revised: 02/27/2024] [Accepted: 03/21/2024] [Indexed: 03/26/2024]
Abstract
Foliar application has been reported as an effective method to facilitate plant growth and mitigate cadmium (Cd) accumulation. However, the application of foliar fertilizers on plant production, Cd uptake and health risks of Solanaceae family remains unknown. In this study, four foliar fertilizers were applied to investigate their effects on the production, Cd accumulation and human health risk assessment of two varieties of pepper (Capsicum annuum L.) and eggplant (Solanum melongena L.), respectively. Compared with CK, the foliar application increased vegetable production to 104.16 %-123.70 % in peppers, and 100.83 %-105.17 % in eggplants, accordingly. The application of foliar fertilizers largely decreased Cd TF (transportation factor) by up to 23.32 % in JY, 18.37 % in GJ of pepper varieties, and up to 14.47 % in ZL, 15.24 % in HGR of eggplant varieties. Moreover, Cd BAF (bioaccumulation factor) also declined to different extents after the application of foliar fertilizers. As for human health risk assessments, foliar application diminished the hazard index (HI) and carcinogenic risk (CR) of both pepper and eggplant varieties. The results concluded that the application of composed foliar fertilizers was most effective, and could be a promising alternative for the improvement of vegetable production and mitigation of vegetable Cd accumulation and human health risks as well. The results further highlighted the understanding of foliar fertilizer application on vegetable production and health risks, which benefited better vegetable safe production and further guaranteed human health.
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Affiliation(s)
- Qiong Wang
- College of Ecology, Taiyuan University of Technology, Taiyuan 030024, People's Republic of China.
| | - Qiyao Zhou
- Management Committee of Yancheng Economic and Technological Development Zone, Yancheng 224000, People's Republic of China
| | - Ying Feng
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, People's Republic of China
| | - Xiaoe Yang
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, People's Republic of China
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Zhang H, Nie M, Du X, Chen S, Liu H, Wu C, Tang Y, Lei Z, Shi G, Zhao X. Selenium and Bacillus proteolyticus SES increased Cu-Cd-Cr uptake by ryegrass: highlighting the significance of key taxa and soil enzyme activity. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:29113-29131. [PMID: 38568308 DOI: 10.1007/s11356-024-32959-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 03/13/2024] [Indexed: 04/24/2024]
Abstract
Many studies have focused their attention on strategies to improve soil phytoremediation efficiency. In this study, a pot experiment was carried out to investigate whether Se and Bacillus proteolyticus SES promote Cu-Cd-Cr uptake by ryegrass. To explore the effect mechanism of Se and Bacillus proteolyticus SES, rhizosphere soil physiochemical properties and rhizosphere soil bacterial properties were determined further. The findings showed that Se and Bacillus proteolyticus SES reduced 23.04% Cu, 36.85% Cd, and 9.85% Cr from the rhizosphere soil of ryegrass. Further analysis revealed that soil pH, organic matter, soil enzyme activities, and soil microbial properties were changed with Se and Bacillus proteolyticus SES application. Notably, rhizosphere key taxa (Bacteroidetes, Actinobacteria, Firmicutes, Patescibacteria, Verrucomicrobia, Chloroflexi, etc.) were significantly enriched in rhizosphere soil of ryegrass, and those taxa abundance were positively correlated with soil heavy metal contents (P < 0.01). Our study also demonstrated that in terms of explaining variations of soil Cu-Cd-Cr content under Se and Bacillus proteolyticus SES treatment, soil enzyme activities (catalase and acid phosphatase) and soil microbe properties showed 42.5% and 12.2% contributions value, respectively. Overall, our study provided solid evidence again that Se and Bacillus proteolyticus SES facilitated phytoextraction of soil Cu-Cd-Cr, and elucidated the effect of soil key microorganism and chemical factor.
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Affiliation(s)
- Huan Zhang
- College of Resources and Environment, Huazhong Agricultural University / Research Center of Trace Elements, Wuhan, 430070, China
- Key Laboratory of Se-Enriched Products Development and Quality Control, Ministry of Agriculture and Rural Affairs/ National-Local Joint Engineering Laboratory of Se-Enriched Food Development, Ankang, 725000, China
| | - Min Nie
- College of Resources and Environment, Huazhong Agricultural University / Research Center of Trace Elements, Wuhan, 430070, China
| | - Xiaoping Du
- Key Laboratory of Se-Enriched Products Development and Quality Control, Ministry of Agriculture and Rural Affairs/ National-Local Joint Engineering Laboratory of Se-Enriched Food Development, Ankang, 725000, China
| | - Suhua Chen
- National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization (Nanchang Hangkong University), Nanchang, 330063, China
| | - Hanliang Liu
- Key Laboratory of Geochemical Exploration, Institute of Geophysical and Geochemical Exploration, CAGS, Langfang, 065000, Hebei, China
| | - Chihhung Wu
- Fujian Provincial Key Laboratory of Resources and Environment Monitoring & Sustainable Management and Utilization, Sanming University, Sanming, 365004, China
| | - Yanni Tang
- College of Resources and Environment, Huazhong Agricultural University / Research Center of Trace Elements, Wuhan, 430070, China
| | - Zheng Lei
- College of Resources and Environment, Huazhong Agricultural University / Research Center of Trace Elements, Wuhan, 430070, China
| | - Guangyu Shi
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Xiaohu Zhao
- College of Resources and Environment, Huazhong Agricultural University / Research Center of Trace Elements, Wuhan, 430070, China.
- Key Laboratory of Se-Enriched Products Development and Quality Control, Ministry of Agriculture and Rural Affairs/ National-Local Joint Engineering Laboratory of Se-Enriched Food Development, Ankang, 725000, China.
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Sanjana S, Jazeel K, Janeeshma E, Nair SG, Shackira AM. Synergistic interactions of assorted ameliorating agents to enhance the potential of heavy metal phytoremediation. STRESS BIOLOGY 2024; 4:13. [PMID: 38363436 PMCID: PMC10873264 DOI: 10.1007/s44154-024-00153-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 01/29/2024] [Indexed: 02/17/2024]
Abstract
Pollution by toxic heavy metals creates a significant impact on the biotic community of the ecosystem. Nowadays, a solution to this problem is an eco-friendly approach like phytoremediation, in which plants are used to ameliorate heavy metals. In addition, various amendments are used to enhance the potential of heavy metal phytoremediation. Symbiotic microorganisms such as phosphate-solubilizing bacteria (PSB), endophytes, mycorrhiza and plant growth-promoting rhizobacteria (PGPR) play a significant role in the improvement of heavy metal phytoremediation potential along with promoting the growth of plants that are grown in contaminated environments. Various chemical chelators (Indole 3-acetic acid, ethylene diamine tetra acetic acid, ethylene glycol tetra acetic acid, ethylenediamine-N, N-disuccinic acid and nitrilotri-acetic acid) and their combined action with other agents also contribute to heavy metal phytoremediation enhancement. With modern techniques, transgenic plants and microorganisms are developed to open up an alternative strategy for phytoremediation. Genomics, proteomics, transcriptomics and metabolomics are widely used novel approaches to develop competent phytoremediators. This review accounts for the synergistic interactions of the ameliorating agent's role in enhancing heavy metal phytoremediation, intending to highlight the importance of these various approaches in reducing heavy metal pollution.
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Affiliation(s)
- S Sanjana
- Department of Botany, Sir Syed College, Kannur University, Kerala, 670142, India
| | - K Jazeel
- Department of Botany, Sir Syed College, Kannur University, Kerala, 670142, India
| | - E Janeeshma
- Department of Botany, MES KEVEEYAM College, Valanchery, Malappuram, Kerala, India
| | - Sarath G Nair
- Department of Botany, Mar Athanasius College, Mahatma Gandhi University, Kottayam, Kerala, India
| | - A M Shackira
- Department of Botany, Sir Syed College, Kannur University, Kerala, 670142, India.
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Wang Z, Zheng Y, Peng J, Zhou F, Yu J, Chi R, Xiao C. Mechanisms of combined bioremediation by phosphate-solubilizing fungus and plants and its effects on cadmium contamination in phosphate-mining wastelands. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 346:118983. [PMID: 37714083 DOI: 10.1016/j.jenvman.2023.118983] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 08/15/2023] [Accepted: 09/09/2023] [Indexed: 09/17/2023]
Abstract
Owing to uncontrolled mining activities and lack of ecological protection measures, phosphate-mining wastelands are contaminated with the heavy metal Cd. In this study, Penicillium oxalicum strain ZP6, a Cd-resistant phosphate-solubilizing fungus, was used in combination with the fast-growing, high-biomass plant Brassica juncea L. to enhance Cd remediation in phosphate-mining wastelands. Further, the bioremediation mechanisms were explored and elucidated. In pot experiments, strain ZP6 and Brassica juncea L. alone were significantly effective in removing Cd from phosphate-mining wastelands; however, their combination was more effective, exhibiting a high removal rate of 88.75%. The presence of phosphorite powder increases soil-enzyme activity, promotes plant growth, and reduces the bioaccumulation and translocation factors. However, Cd-inhibited plant growth and chlorophyll content increased malondialdehyde accumulation, which was alleviated by inoculation with strain ZP6. The results from the study indicate that bioremediation using a combination of strain ZP6 and plants is a restoration strategy with appreciable potential to resolve Cd contamination in phosphate-mining wastelands.
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Affiliation(s)
- Ziwei Wang
- Key Laboratory of Novel Biomass-Based Environmental and Energy Materials in Petroleum and Chemical Industry, Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education, School of Environmental Ecology and Biological Engineering, Wuhan Institute of Technology, Wuhan 430205, China
| | - Yunting Zheng
- Key Laboratory of Novel Biomass-Based Environmental and Energy Materials in Petroleum and Chemical Industry, Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education, School of Environmental Ecology and Biological Engineering, Wuhan Institute of Technology, Wuhan 430205, China
| | - Jun Peng
- Key Laboratory of Novel Biomass-Based Environmental and Energy Materials in Petroleum and Chemical Industry, Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education, School of Environmental Ecology and Biological Engineering, Wuhan Institute of Technology, Wuhan 430205, China
| | - Fang Zhou
- Key Laboratory of Novel Biomass-Based Environmental and Energy Materials in Petroleum and Chemical Industry, Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education, School of Environmental Ecology and Biological Engineering, Wuhan Institute of Technology, Wuhan 430205, China
| | - Junxia Yu
- Key Laboratory of Novel Biomass-Based Environmental and Energy Materials in Petroleum and Chemical Industry, Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education, School of Environmental Ecology and Biological Engineering, Wuhan Institute of Technology, Wuhan 430205, China
| | - Ruan Chi
- Key Laboratory of Novel Biomass-Based Environmental and Energy Materials in Petroleum and Chemical Industry, Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education, School of Environmental Ecology and Biological Engineering, Wuhan Institute of Technology, Wuhan 430205, China; Hubei Three Gorges Laboratory, Yichang, 443007, China
| | - Chunqiao Xiao
- Key Laboratory of Novel Biomass-Based Environmental and Energy Materials in Petroleum and Chemical Industry, Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education, School of Environmental Ecology and Biological Engineering, Wuhan Institute of Technology, Wuhan 430205, China; Hubei Three Gorges Laboratory, Yichang, 443007, China.
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7
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Qu H, Wang Y, Wang B, Li C. Pulsed electric field treatment of seeds altered the endophytic bacterial community and promotes early growth of roots in buckwheat. BMC Microbiol 2023; 23:290. [PMID: 37833633 PMCID: PMC10571398 DOI: 10.1186/s12866-023-02943-5] [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: 03/15/2023] [Accepted: 07/12/2023] [Indexed: 10/15/2023] Open
Abstract
BACKGROUND Endophytic bacteria provide nutrients and stimulate systemic resistance during seed germination and plant growth and development, and their functional properties in combating various stresses make them a powerful tool in green agricultural production. In this paper we explored the function of the endophyte community in buckwheat seeds in order to provide a theoretical basis for the application and scientific research of endophytes in buckwheat cultivation. We used pulsed electric field (PEF) technology to treat buckwheat seeds, monitored the effect of high-voltage pulse treatment on buckwheat seed germination, and analyzed the diversity of endophytic bacteria in buckwheat seeds using the amplicon sequencing method. RESULTS PEF treatment promoted root development during buckwheat seed germination. A total of 350 Operational taxonomic units (OTUs) that were assigned into 103 genera were obtained from control and treatment groups using 16SrRNA amplicon sequencing technology. Additionally, PEF treatment also caused a significant decrease in the abundance of Actinobacteria, Proteobacteria, and Bacteroidetes. The abundance of 28 genera changed significantly as well: 11 genera were more abundant, and 17 were less abundant. The number of associated network edges was reduced from 980 to 117, the number of positive correlations decreased by 89.1%, and the number of negative correlations decreased by 86.6%. CONCLUSION PEF treatment promoted early root development in buckwheat and was able to alter the seed endophytic bacterial community. This study thus makes a significant contribution to the field of endophyte research and to the application of PEF technology in plant cultivation.
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Affiliation(s)
- Hao Qu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China
- Tea Research Institute, Yunnan Academy of Agricultural Sciences, Menghai, China
| | - Yi Wang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China
- Yunnan-CABI Joint Laboratory for Integrated Prevention and Control of Trans-boundary Pests, Yunnan Agricultural University, Kunming, China
| | - Baijuan Wang
- College of Tea Science, Yunnan Agricultural University, Kunming, China.
| | - Chengyun Li
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, China.
- Yunnan-CABI Joint Laboratory for Integrated Prevention and Control of Trans-boundary Pests, Yunnan Agricultural University, Kunming, China.
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Shehzad J, Khan I, Zaheer S, Farooq A, Chaudhari SK, Mustafa G. Insights into heavy metal tolerance mechanisms of Brassica species: physiological, biochemical, and molecular interventions. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:108448-108476. [PMID: 37924172 DOI: 10.1007/s11356-023-29979-4] [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: 05/02/2023] [Accepted: 09/15/2023] [Indexed: 11/06/2023]
Abstract
Heavy metal (HM) contamination of soil due to anthropogenic activities has led to bioaccumulation and biomagnification, posing toxic effects on plants by interacting with vital cellular biomolecules such as DNA and proteins. Brassica species have developed complex physiological, biochemical, and molecular mechanisms for adaptability, tolerance, and survival under these conditions. This review summarizes the HM tolerance strategies of Brassica species, covering the role of root exudates, microorganisms, cell walls, cell membranes, and organelle-specific proteins. The first line of defence against HM stress in Brassica species is the avoidance strategy, which involves metal ion precipitation, root sorption, and metal exclusion. The use of plant growth-promoting microbes, Pseudomonas, Psychrobacter, and Rhizobium species effectively immobilizes HMs and reduces their uptake by Brassica roots. The roots of Brassica species efficiently detoxify metals, particularly by flavonoid glycoside exudation. The composition of the cell wall and callose deposition also plays a crucial role in enhancing HMs resistance in Brassica species. Furthermore, plasma membrane-associated transporters, BjCET, BjPCR, BjYSL, and BnMTP, reduce HM concentration by stimulating the efflux mechanism. Brassica species also respond to stress by up-regulating existing protein pools or synthesizing novel proteins associated with HM stress tolerance. This review provides new insights into the HM tolerance mechanisms of Brassica species, which are necessary for future development of HM-resistant crops.
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Affiliation(s)
- Junaid Shehzad
- Department of Plant Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, 45320, Pakistan
| | - Ilham Khan
- Department of Plant Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, 45320, Pakistan
| | - Saira Zaheer
- Department of Plant Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, 45320, Pakistan
| | - Atikah Farooq
- Department of Plant Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, 45320, Pakistan
| | - Sunbal Khalil Chaudhari
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Sargodha Campus, Sargodha, 42100, Pakistan
| | - Ghazala Mustafa
- Department of Plant Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, 45320, Pakistan.
- Lishui Institute of Agriculture and Forestry Sciences, Lishui, 323000, China.
- State Agricultural Ministry Laboratory of Horticultural Crop growth and Development, Ministry of Agri-culture, Department of Horticulture, Zhejiang University, Hangzhou, 310058, China.
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9
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Qi J, Fu D, Wang X, Zhang F, Ma C. The effect of alfalfa cultivation on improving physicochemical properties soil microorganisms community structure of grey desert soil. Sci Rep 2023; 13:13747. [PMID: 37612457 PMCID: PMC10447519 DOI: 10.1038/s41598-023-41005-8] [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: 04/03/2023] [Accepted: 08/20/2023] [Indexed: 08/25/2023] Open
Abstract
Planting alfalfa in grey desert soil can have significant effects on soil nutrient levels, microbial communities, and overall soil improvement. High-throughput sequencing technology was used to explore the relationship between the rhizosphere microbial community structure of grey desert soil planted with different alfalfa varieties (Aohan, WL525HQ, Knight2, Kangsai, Victoria, and WL712), alfalfa characteristics and rhizosphere soil physicochemical properties. Alfalfa planting increased the nitrogen and organic matter in the grey desert soil, and the effects in Victoria, Kangsai, and Aohan were relatively better than those in the unplanted areas and other alfalfa areas. The Chao1 and Shannon indexes showed that the diversity and relative abundance of bacteria and fungi in Kangsai were significantly higher than those in the unplanted areas and other alfalfa areas. Redundancy analysis showed that available nitrogen and phosphorus, as well as fresh weight, significantly affected the changes in fungal and bacterial communities. Variance partitioning analysis showed that soil and alfalfa growth characteristics explained 50.04% and 51.58% of the structural changes in the bacteria and fungi, respectively. Therefore, planting alfalfa changed the community structure of bacteria and fungi, as well as the content of soil nutrients, and different varieties of alfalfa had different effects on soil improvement.
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Affiliation(s)
- Jiangjiao Qi
- College of Animal Science & Technology, Shihezi University, Shihezi, 832003, Xinjiang, China
| | - Dongqing Fu
- College of Animal Science & Technology, Shihezi University, Shihezi, 832003, Xinjiang, China
| | - Xuzhe Wang
- College of Animal Science & Technology, Shihezi University, Shihezi, 832003, Xinjiang, China
| | - Fanfan Zhang
- College of Animal Science & Technology, Shihezi University, Shihezi, 832003, Xinjiang, China
| | - Chunhui Ma
- College of Animal Science & Technology, Shihezi University, Shihezi, 832003, Xinjiang, China.
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Tian Q, Gong Y, Liu S, Ji M, Tang R, Kong D, Xue Z, Wang L, Hu F, Huang L, Qin S. Endophytic bacterial communities in wild rice ( Oryza officinalis) and their plant growth-promoting effects on perennial rice. FRONTIERS IN PLANT SCIENCE 2023; 14:1184489. [PMID: 37645460 PMCID: PMC10461003 DOI: 10.3389/fpls.2023.1184489] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Accepted: 07/24/2023] [Indexed: 08/31/2023]
Abstract
Endophytic bacterial microbiomes of plants contribute to the physiological health of the host and its adaptive evolution and stress tolerance. Wild rice possesses enriched endophytic bacteria diversity, which is a potential resource for sustainable agriculture. Oryza officinalis is a unique perennial wild rice species in China with rich genetic resources. However, endophytic bacterial communities of this species and their plant growth-promoting (PGP) traits remain largely unknown. In this study, endophytic bacteria in the root, stem, and leaf tissues of O. officinalis were characterized using 16S rRNA gene Illumina sequencing. Culturable bacterial endophytes were also isolated from O. officinalis tissues and characterized for their PGP traits. The microbiome analysis showed a more complex structure and powerful function of the endophytic bacterial community in roots compared with those in other tissue compartments. Each compartment had its specific endophytic bacterial biomarkers, including Desulfomonile and Ruminiclostridium for roots; Lactobacillus, Acinetobacter, Cutibacterium and Dechloromonas for stems; and Stenotrophomonas, Chryseobacterium, Achromobacter and Methylobacterium for leaves. A total of 96 endophytic bacterial strains with PGP traits of phosphate solubilization, potassium release, nitrogen fixation, 1-aminocyclopropane-1-carboxylate (ACC) deaminase secretion, and siderophore or indole-3-acetic acid (IAA) production were isolated from O. officinalis. Among them, 11 strains identified as Enterobacter mori, E. ludwigii, E. cloacae, Bacillus amyloliquefaciens, B. siamensis, Pseudomonas rhodesiae and Kosakonia oryzae were selected for inoculation of perennial rice based on their IAA production traits. These strains showed promising PGP effects on perennial rice seedlings. They promoted plants to form a strong root system, stimulate biomass accumulation, and increase chlorophyll content and nitrogen uptake, which could fulfil the ecologically sustainable cultivation model of perennial rice. These results provide insights into the bacterial endosphere of O. officinalis and its application potential in perennial rice. There is the prospect of mining beneficial endophytic bacteria from wild rice species, which could rewild the microbiome of cultivated rice varieties and promote their growth.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Fengyi Hu
- Key Laboratory of Biology and Germplasm Innovation of Perennial Rice From Ministry of Agriculture and Rural Affairs, School of Agriculture, Yunnan University, Kunming, Yunnan, China
| | - Liyu Huang
- Key Laboratory of Biology and Germplasm Innovation of Perennial Rice From Ministry of Agriculture and Rural Affairs, School of Agriculture, Yunnan University, Kunming, Yunnan, China
| | - Shiwen Qin
- Key Laboratory of Biology and Germplasm Innovation of Perennial Rice From Ministry of Agriculture and Rural Affairs, School of Agriculture, Yunnan University, Kunming, Yunnan, China
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11
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Mazoyon C, Catterou M, Alahmad A, Mongelard G, Guénin S, Sarazin V, Dubois F, Duclercq J. Sphingomonas sediminicola Dae20 Is a Highly Promising Beneficial Bacteria for Crop Biostimulation Due to Its Positive Effects on Plant Growth and Development. Microorganisms 2023; 11:2061. [PMID: 37630621 PMCID: PMC10459697 DOI: 10.3390/microorganisms11082061] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/08/2023] [Accepted: 08/09/2023] [Indexed: 08/27/2023] Open
Abstract
Current agricultural practices rely heavily on synthetic fertilizers, which not only consume a lot of energy but also disrupt the ecological balance. The overuse of synthetic fertilizers has led to soil degradation. In a more sustainable approach, alternative methods based on biological interactions, such as plant growth-promoting bacteria (PGPRs), are being explored. PGPRs, which include both symbiotic and free-living bacteria, form mutualistic relationships with plants by enhancing nutrient availability, producing growth regulators, and regulating stress responses. This study investigated the potential of Sphingomonas sediminicola Dae20, an α-Proteobacteria species commonly found in the rhizosphere, as a beneficial PGPR. We observed that S. sediminicola Dae20 stimulated the root system and growth of three different plant species in the Brassicaceae family, including Arabidopsis thaliana, mustard, and rapeseed. The bacterium produced auxin, nitric oxide, siderophores and showed ACC deaminase activity. In addition to activating an auxin response in the plant, S. sediminicola Dae20 exhibited the ability to modulate other plant hormones, such as abscisic acid, jasmonic acid and salicylic acid, which are critical for plant development and defense responses. This study highlights the multifunctional properties of S. sediminicola Dae20 as a promising PGPR and underscores the importance of identifying effective and versatile beneficial bacteria to improve plant nutrition and promote sustainable agricultural practices.
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Affiliation(s)
- Candice Mazoyon
- Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN, UMR7058 CNRS), Université de Picardie Jules Verne (UPJV), 80000 Amiens, France; (C.M.); (M.C.); (A.A.); (F.D.)
| | - Manuella Catterou
- Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN, UMR7058 CNRS), Université de Picardie Jules Verne (UPJV), 80000 Amiens, France; (C.M.); (M.C.); (A.A.); (F.D.)
| | - Abdelrahman Alahmad
- Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN, UMR7058 CNRS), Université de Picardie Jules Verne (UPJV), 80000 Amiens, France; (C.M.); (M.C.); (A.A.); (F.D.)
- Agroécologie, Hydrogéochimie, Milieux et Ressources (AGHYLE, UP2018.C101) UniLaSalle Rouen, SFR NORVEGE FED 4277, 76130 Mont-Saint Aignan, France
| | - Gaëlle Mongelard
- Centre de Ressources Régionales en Biologie Moléculaire (CRRBM), Université de Picardie Jules Verne (UPJV), 80000 Amiens, France; (G.M.); (S.G.)
| | - Stéphanie Guénin
- Centre de Ressources Régionales en Biologie Moléculaire (CRRBM), Université de Picardie Jules Verne (UPJV), 80000 Amiens, France; (G.M.); (S.G.)
| | | | - Fréderic Dubois
- Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN, UMR7058 CNRS), Université de Picardie Jules Verne (UPJV), 80000 Amiens, France; (C.M.); (M.C.); (A.A.); (F.D.)
| | - Jérôme Duclercq
- Ecologie et Dynamique des Systèmes Anthropisés (EDYSAN, UMR7058 CNRS), Université de Picardie Jules Verne (UPJV), 80000 Amiens, France; (C.M.); (M.C.); (A.A.); (F.D.)
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12
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Guo L, Ling L, Wang X, Cheng T, Wang H, Ruan Y. Exogenous hydrogen sulfide and methylglyoxal alleviate cadmium-induced oxidative stress in Salix matsudana Koidz by regulating glutathione metabolism. BMC PLANT BIOLOGY 2023; 23:73. [PMID: 36732696 PMCID: PMC9893619 DOI: 10.1186/s12870-023-04089-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 01/27/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND Cadmium (Cd) is a highly toxic element for plant growth. In plants, hydrogen sulfide (H2S) and methylglyoxal (MG) have emerged as vital signaling molecules that regulate plant growth processes under Cd stress. However, the effects of sodium hydrosulfide (NaHS, a donor of H2S) and MG on Cd uptake, physiological responses, and gene expression patterns of Salix to Cd toxicity have been poorly understood. Here, Salix matsudana Koidz. seedlings were planted in plastic pot with applications of MG (108 mg kg- 1) and NaHS (50 mg kg- 1) under Cd (150 mg kg- 1) stress. RESULTS Cd treatment significantly increased the reactive oxygen species (ROS) levels and malondialdehyde (MDA) content, but decreased the growth parameters in S. matsudana. However, NaHS and MG supplementation significantly decreased Cd concentration, ROS levels, and MDA content, and finally enhanced the growth parameters. Cd stress accelerated the activities of antioxidative enzymes and the relative expression levels of stress-related genes, which were further improved by NaHS and MG supplementation. However, the activities of monodehydroascorbate reductase (MDHAR), and dehydroascorbate reductase (DHAR) were sharply decreased under Cd stress. Conversely, NaHS and MG applications restored the MDHAR and DHAR activities compared with Cd-treated seedlings. Furthermore, Cd stress decreased the ratios of GSH/GSSG and AsA/DHA but considerably increased the H2S and MG levels and glyoxalase I-II system in S. matsudana, while the applications of MG and NaHS restored the redox status of AsA and GSH and further improved glyoxalase II activity. In addition, compared with AsA, GSH showed a more sensitive response to exogenous applications of MG and NaHS and plays more important role in the detoxification of Cd. CONCLUSIONS The present study illustrated the crucial roles of H2S and MG in reducing ROS-mediated oxidative damage to S. matsudana and revealed the vital role of GSH metabolism in regulating Cd-induced stress.
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Affiliation(s)
- Long Guo
- School of Life Science, Liaoning University, Shenyang, 110036, China
| | - Long Ling
- School of Life Science, Liaoning University, Shenyang, 110036, China
| | - Xiaoqian Wang
- School of Life Science, Liaoning University, Shenyang, 110036, China
| | - Ting Cheng
- School of Life Science, Liaoning University, Shenyang, 110036, China
| | - Hongyan Wang
- School of Life Science, Liaoning University, Shenyang, 110036, China
| | - Yanan Ruan
- School of Life Science, Liaoning University, Shenyang, 110036, China.
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13
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Jin X, Rahman MKU, Ma C, Zheng X, Wu F, Zhou X. Silicon modification improves biochar's ability to mitigate cadmium toxicity in tomato by enhancing root colonization of plant-beneficial bacteria. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 249:114407. [PMID: 36508786 DOI: 10.1016/j.ecoenv.2022.114407] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 11/16/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
Modification of biochar, such as impregnation with minerals, can improve biochar's efficacy to mitigate heavy metal toxicity in plants. Biochar amendments can alter plant rhizosphere microbiome, which has profound effects on plant growth and fitness. Here, we tested whether rhizosphere microbiome is involved in the ability of silicon (Si)-modified biochar to mitigate cadmium toxicity in tomato (Solanum lycopersicum L.). We demonstrated that Si modification altered biochar's physico-chemical properties and enhanced its ability to mitigate cadmium toxicity in tomato. Particularly, the Si-modified biochar contained higher content of Si and increased plant-available Si content in the soil. The rhizosphere microbiome transplant experiment showed that changes in rhizosphere microbiome contributed to the mitigation of cadmium toxicity by biochar amendments. The raw biochar and Si-modified biochar differently altered tomato rhizosphere bacterial community composition. Both biochars, especially the Si-modified biochar, promoted specific bacterial taxa (e.g., Sphingomonas, Lysobacter and Pseudomonas spp.). Subsequent culturing found these promoted bacteria could mitigate cadmium toxicity in tomato. Moreover, both biochars stimulated tomato to recruit plant-beneficial bacteria with Si-modified biochar having stronger stimulatory effects, indicating that the positive effects of biochar on plant-beneficial bacteria was partially mediated via the host plant. Overall, Si modification enhanced biochar's ability to mitigate cadmium toxicity, which was linked to the stimulatory effects on plant-beneficial bacteria.
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Affiliation(s)
- Xue Jin
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Department of Horticulture, Northeast Agricultural University, Harbin 150030, China
| | - Muhammad Khashi U Rahman
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Department of Horticulture, Northeast Agricultural University, Harbin 150030, China
| | - Changli Ma
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Department of Horticulture, Northeast Agricultural University, Harbin 150030, China
| | - Xianqing Zheng
- Institute of Eco-Environment and Plant Protection, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China
| | - Fengzhi Wu
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Department of Horticulture, Northeast Agricultural University, Harbin 150030, China
| | - Xingang Zhou
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Department of Horticulture, Northeast Agricultural University, Harbin 150030, China.
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14
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Wang M, Chen Z, Chen D, Liu L, Hamid Y, Zhang S, Shan A, Kang KJ, Feng Y, Yang X. Combined cadmium and fluorine inhibit lettuce growth through reducing root elongation, photosynthesis, and nutrient absorption. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:91255-91267. [PMID: 35882734 DOI: 10.1007/s11356-022-22195-6] [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: 01/10/2022] [Accepted: 07/20/2022] [Indexed: 06/15/2023]
Abstract
Cadmium (Cd) and fluorine (F) often coexist in environment and are toxic to organisms; however, their combined effects on plants are still not well documented. In this study, the co-effects of Cd and F on germination, biomass, photosynthesis, and nutrients uptake of lettuce were carried out in hydroponic culture. The results showed that the seed germination and seedling biomass decreased with an increase in Cd and F supplementation. The root morphology verified these effects as excess combined Cd and F diminished the root tips and surface area of lettuce, while single Cd and F inhibited the growth by decreasing root length and average diameter, respectively. These effects were also consistence with a reduction in photosynthesis which was mainly regulated by reducing the quantum yield of PS II, electron transport activity, stomatal conductance, intercellular CO2 concentration, and transpiration rate in response to the pollutants. Moreover, when lettuce exposed to Cd and F stress, the accumulation of several essential elements in shoot decreased. In a sum, the synergistic negative effects of Cd and F on the seed germination and seedling growth of lettuce were observed, and these might be owed to nutrient absorption and translocation in the plant. These findings aid in understanding the harmful effects and specific mechanisms of action of Cd and F on plants.
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Affiliation(s)
- Mei Wang
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Zijingang Campus, Yuhangtang Road 866, Hangzhou, 310058, China
| | - Zhiqin Chen
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Zijingang Campus, Yuhangtang Road 866, Hangzhou, 310058, China
| | - Dan Chen
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Zijingang Campus, Yuhangtang Road 866, Hangzhou, 310058, China
| | - Lei Liu
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Zijingang Campus, Yuhangtang Road 866, Hangzhou, 310058, China
| | - Yasir Hamid
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Zijingang Campus, Yuhangtang Road 866, Hangzhou, 310058, China
| | - Shijun Zhang
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Zijingang Campus, Yuhangtang Road 866, Hangzhou, 310058, China
| | - Anqi Shan
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Zijingang Campus, Yuhangtang Road 866, Hangzhou, 310058, China
| | - Kyong Ju Kang
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Zijingang Campus, Yuhangtang Road 866, Hangzhou, 310058, China
| | - Ying Feng
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Zijingang Campus, Yuhangtang Road 866, Hangzhou, 310058, China
| | - Xiaoe Yang
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Zijingang Campus, Yuhangtang Road 866, Hangzhou, 310058, China.
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15
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Yao Y, Zhang X, Huang Z, Li H, Huang J, Corti G, Wu Z, Qin X, Zhang Y, Ye X, Fan H, Jiang L. A field study on the composition, structure, and function of endophytic bacterial community of Robinia pseudoacacia at a composite heavy metals tailing. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 850:157874. [PMID: 35940266 DOI: 10.1016/j.scitotenv.2022.157874] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 08/02/2022] [Accepted: 08/02/2022] [Indexed: 05/27/2023]
Abstract
Robinia pseudoacacia (R. pseudoacacia) is a well reported plant species for heavy metal phytoremediation, and it was capable to improve Cd uptake efficiency after inoculated with plant growth promoting endophytes. However, the knowledge on R. pseudoacacia associated endophytes in field condition and the relationship between these microbial communities and heavy metal uptake capacities are still scarce. In this study, the characteristics of heavy metal bioaccumulation and translocation in R. pseudoacacia, and the structure and function of its endophytic bacterial communities were revealed. The results showed that heavy metal pollution made microbes more sensitive to the environment as the diversity (Shannon) of endophyte community decreased but the abundance (Chao) increased. Redundancy analysis (RDA) also showed that heavy metals were the key factor affecting the composition of endophyte. In the co-occurrence network, 27 keystone taxa mainly from Actinobacteria, Proteobacteria and Firmicutes occupied the dominant niches, among which 16 OTUs mainly from lactobacillus, bacteroides, staphylococcus, methylorubrum and bifidobacterium were positively related to bioaccumulation and translocation of Cd, Cu, Pb and Zn. Besides, heavy metal stress enhanced the functional adaptability of endophytic bacteria community. Related predicted genes were enriched in immune response, physiological metabolism pathway and stress-resistant enzyme synthesis. This study showed that heavy metal stress enhanced the structural and functional adaptability of endophyte community and keystone taxa played significant role in improving the efficiency of phytoremediation.
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Affiliation(s)
- Yuxuan Yao
- College of Life Science and Technology, Central South University of Forestry and Technology, 498 South Shaoshan Road, Changsha, Hunan 410004, PR China; State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, Hunan 410004, PR China
| | - Xuan Zhang
- College of Life Science and Technology, Central South University of Forestry and Technology, 498 South Shaoshan Road, Changsha, Hunan 410004, PR China; State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, Hunan 410004, PR China
| | - Zhongliang Huang
- State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, Hunan 410004, PR China
| | - Hui Li
- State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, Hunan 410004, PR China
| | - Jing Huang
- State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, Hunan 410004, PR China
| | - Giuseppe Corti
- Department of Agrarian, Food and Environmental Sciences, Università Politecnica dell Marche, Ancona, Italy
| | - Zijian Wu
- State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, Hunan 410004, PR China
| | - Xiaoli Qin
- State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, Hunan 410004, PR China
| | - Yanru Zhang
- State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, Hunan 410004, PR China
| | - Xinyu Ye
- State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, Hunan 410004, PR China
| | - Huixin Fan
- College of Life Science and Technology, Central South University of Forestry and Technology, 498 South Shaoshan Road, Changsha, Hunan 410004, PR China; State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, Hunan 410004, PR China
| | - Lijuan Jiang
- College of Life Science and Technology, Central South University of Forestry and Technology, 498 South Shaoshan Road, Changsha, Hunan 410004, PR China.
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16
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Waheed A, Haxim Y, Islam W, Ahmad M, Ali S, Wen X, Khan KA, Ghramh HA, Zhang Z, Zhang D. Impact of Cadmium Stress on Growth and Physio-Biochemical Attributes of Eruca sativa Mill. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11212981. [PMID: 36365433 PMCID: PMC9654351 DOI: 10.3390/plants11212981] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 10/15/2022] [Accepted: 11/01/2022] [Indexed: 05/30/2023]
Abstract
Plants may experience adverse effects from Cadmium (Cd). As a result of its toxicity and mobility within the soil-plant continuum, it is attracting the attention of soil scientists and plant nutritionists. In this study, we subjected young Eruca sativa Mill. seedlings to different levels of Cd applications (0, 1.5, 6 and 30 µmol/L) via pot experiment to explore its morpho-physio-biochemical adaptations. Our results revealed a significant Cd accumulation in leaves at high Cd stress. It was also demonstrated that Cd stress inhibited photosynthetic rate and pigment levels, ascorbate peroxidase (APX), guaiacol peroxidase (GPX), catalase (CAT), and superoxide dismutase (SOD) enzyme activities, and increased malondialdehyde (MDA) levels. Conversely, the concentration of total ascorbate (TAS) increased at all levels of Cd application, whereas that of ascorbic acid (ASA), and dehydroascorbate (DHA) increased at 1.5 (non-significant), 6, 30 and 6 µmol/L (significant), though their concentrations decreased non-significantly at 30 µmol/L application. In conclusion, Cd-subjected E. sativa seedlings diverted much energy from growth towards the synthesis of anti-oxidant metabolites and osmolytes. However, they did not seem to have protected the E. sativa seedlings from Cd-induced oxidative stress, causing a decrease in osmotic adjustment, and an increase in oxidative damage, which resulted in a reduction in photosynthesis and growth. Accordingly, we recommend that the cultivation of E. sativa should be avoided on soil with Cd contamination.
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Affiliation(s)
- Abdul Waheed
- National Key Laboratory of Ecological Security and Resource Utilization in Arid Areas, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Xinjiang Key Laboratory of Conservation and Utilization of Plant Gene Resources, Xinjiang Institute of Ecology & Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Turpan Eremophytes Botanical Garden, Chinese Academy of Sciences, Turpan 838008, China
| | - Yakupjan Haxim
- National Key Laboratory of Ecological Security and Resource Utilization in Arid Areas, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Xinjiang Key Laboratory of Conservation and Utilization of Plant Gene Resources, Xinjiang Institute of Ecology & Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Turpan Eremophytes Botanical Garden, Chinese Academy of Sciences, Turpan 838008, China
| | - Waqar Islam
- Xinjiang Key Laboratory of Conservation and Utilization of Plant Gene Resources, Xinjiang Institute of Ecology & Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Xinjiang Key Laboratory of Desert Plant Roots Ecology and Vegetation Restoration, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
| | - Mushtaq Ahmad
- Department of Zoology, Islamia College University, Peshawar 25120, Pakistan
| | - Sajjad Ali
- Department of Botany, Bacha Khan University, Charsadda 24461, Pakistan
| | - Xuejing Wen
- National Key Laboratory of Ecological Security and Resource Utilization in Arid Areas, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Xinjiang Key Laboratory of Conservation and Utilization of Plant Gene Resources, Xinjiang Institute of Ecology & Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Turpan Eremophytes Botanical Garden, Chinese Academy of Sciences, Turpan 838008, China
| | - Khalid Ali Khan
- Unit of Bee Research and Honey Production, King Khalid University, Abha 61413, Saudi Arabia
- Applied College, Mahala Campus, King Khalid University, Abha 61413, Saudi Arabia
- Biology Department Faculty of Science, King Khalid University, Abha 61413, Saudi Arabia
| | - Hamed A. Ghramh
- Unit of Bee Research and Honey Production, King Khalid University, Abha 61413, Saudi Arabia
- Applied College, Mahala Campus, King Khalid University, Abha 61413, Saudi Arabia
- Biology Department Faculty of Science, King Khalid University, Abha 61413, Saudi Arabia
| | - Zhuqi Zhang
- Binzhou Vocational College, Binzhou 256603, China
| | - Daoyuan Zhang
- National Key Laboratory of Ecological Security and Resource Utilization in Arid Areas, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Xinjiang Key Laboratory of Conservation and Utilization of Plant Gene Resources, Xinjiang Institute of Ecology & Geography, Chinese Academy of Sciences, Urumqi 830011, China
- Turpan Eremophytes Botanical Garden, Chinese Academy of Sciences, Turpan 838008, China
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17
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Zhou X, Zhang X, Ma C, Wu F, Jin X, Dini-Andreote F, Wei Z. Biochar amendment reduces cadmium uptake by stimulating cadmium-resistant PGPR in tomato rhizosphere. CHEMOSPHERE 2022; 307:136138. [PMID: 36002065 DOI: 10.1016/j.chemosphere.2022.136138] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Revised: 08/06/2022] [Accepted: 08/17/2022] [Indexed: 06/15/2023]
Abstract
Biochar amendment in the soil can exert a positive effect in reducing heavy metal toxicity in plants. However, it remains unclear the extent to which this effect is associated with the modulation of plant growth-promoting rhizobacteria (PGPR). Here, we initially conducted a pot experiment using tomato (Solanum lycopersicum L.) as a model plant grown in soil spiked with cadmium. First, we found biochar amendment to result in reduced cadmium uptake in tomato plants and trackable changes in the tomato rhizosphere microbiome. Then, a rhizosphere transplant experiment validated the importance of this microbiome modulation for cadmium-toxicity amelioration. Sequence-based analyses targeted the isolation of representative isolates of PGPR, including Bacillus and Flavisolibacter spp. that displayed in vitro cadmium tolerance and biosorption capabilities (in addition to abilities to solubilize phosphate and produce indole acetic acid). Last, we performed a soil inoculation experiment and confirmed the effectiveness of these isolates in reducing cadmium toxicity in tomato plants. Besides, we found the inoculation of these taxa as single inoculant and in combination to result in increased activities of specific antioxidant enzymes in tomato tissues. Taken together, this study revealed the ecological and physiological mechanisms by which biochar amendment indirectly alleviate cadmium toxicity in tomato plants, in this case, via the modulation and activity of specific PGPR populations. This study provides new insights into strategies able to promote beneficial PGPR in the rhizosphere with potential application to ameliorate heavy metal toxicity in plants.
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Affiliation(s)
- Xingang Zhou
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Department of Horticulture, Northeast Agricultural University, Harbin, 150030, PR China
| | - Xianhong Zhang
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Department of Horticulture, Northeast Agricultural University, Harbin, 150030, PR China
| | - Changli Ma
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Department of Horticulture, Northeast Agricultural University, Harbin, 150030, PR China
| | - Fengzhi Wu
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Department of Horticulture, Northeast Agricultural University, Harbin, 150030, PR China
| | - Xue Jin
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Department of Horticulture, Northeast Agricultural University, Harbin, 150030, PR China.
| | - Francisco Dini-Andreote
- Department of Plant Science & Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA
| | - Zhong Wei
- 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, Nanjing, 210095, PR China.
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18
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Combined Plant Growth-Promoting Bacteria Inoculants Were More Beneficial than Single Agents for Plant Growth and Cd Phytoextraction of Brassica juncea L. during Field Application. TOXICS 2022; 10:toxics10070396. [PMID: 35878301 PMCID: PMC9318595 DOI: 10.3390/toxics10070396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 07/12/2022] [Accepted: 07/16/2022] [Indexed: 11/16/2022]
Abstract
Single or combined plant growth-promoting bacteria (PGPB) strains were widely applied as microbial agents in cadmium (Cd) phytoextraction since they could promote plant growth and facilitate Cd uptake. However, the distinct functional effects between single and combined inoculants have not yet been elucidated. In this study, a field experiment was conducted with single, double and triple inoculants to clarify their divergent impacts on plant growth, Cd uptake and accumulation at different growth stages of Brassica juncea L. by three different PGPB strains (Cupriavidus SaCR1, Burkholdria SaMR10 and Sphingomonas SaMR12). The results show that SaCR1 + SaMR10 + SaMR12 combined inoculants were more effective for growth promotion at the bud stage, flowering stage, and mature stage. Single/combined PGPB agents of SaMR12 and SaMR10 were more efficient for Cd uptake promotion. In addition, SaMR10 + SaMR12 combined the inoculants greatly facilitated Cd uptake and accumulation in shoots, and enhanced the straw Cd extraction rates by 156%. Therefore, it is concluded that the application of PGPB inoculants elevated Cd phytoextraction efficiency, and the combined inoculants were more conductive than single inoculants. These results enriched the existing understanding of PGPB agents and provided technical support for the further exploration of PGPB interacting mechanisms strains on plant growth and Cd phytoextraction, which helped establish an efficient plant–microbe combined phytoremediation system and augment the phytoextraction efficiency in Cd-contaminated farmlands.
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19
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Wang Q, Zhou Q, Huang L, Xu S, Fu Y, Hou D, Feng Y, Yang X. Cadmium phytoextraction through Brassica juncea L. under different consortia of plant growth-promoting bacteria from different ecological niches. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 237:113541. [PMID: 35483144 DOI: 10.1016/j.ecoenv.2022.113541] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 04/14/2022] [Accepted: 04/17/2022] [Indexed: 06/14/2023]
Abstract
Combined bioaugmentation inoculants composed of two or more plant growth-promoting bacteria (PGPB) were more effective than single inoculants for plant growth and cadmium (Cd) removal in contaminated soils. However, the principles of consortia construction still need to be discovered. Here, a pot experiment with Cd natural polluted soil was conducted and PGPB consortia with different ecological niches from hyperaccumulator Sedum alfredii Hance were used to compare their effects and mechanisms on plant growth condition, Cd phytoextraction efficiency, soil enzymatic activities, and rhizospheric bacterial community of Brassica juncea L. The results showed that both rhizospheric and endophytic PGPB consortia inoculants promoted plant growth (6.9%-22.1%), facilitated Cd uptake (230.0%-350.0%) of oilseed rape, increased Cd phytoextraction efficiency (343.0%-441.0%), and enhanced soil Cd removal rates (92.0%-144.0%). PGPB consortia inoculants also enhanced soil microbial carbon by 22.2%-50.5%, activated the activities of soil urease and sucrase by 74.7%-158.4% and 8.4%-61.3%, respectively. Simultaneously, PGPB consortia inoculants increased the relative abundance of Flavobacterium, Rhodanobacter, Kosakonia, Pseudomonas and Paraburkholderia at the genus level, which may be beneficial to plant growth promotion and bacterial phytopathogen biocontrol. Although the four PGPB consortia inoculants promoted oilseed growth, amplified Cd phytoextraction, and changed bacterial community structure in rhizosphere soil, their original ecological niches were not a decisive factor for the efficiency of PGPB consortia. therefore, the results enriched the present knowledge regarding the significant roles of PGPB consortia as bioaugmentation agents and preliminarily explored construction principles of effective bioaugmentation inoculants, which will provide insights into the microbial responses to combined inoculation in the Cd-contaminated soils.
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Affiliation(s)
- Qiong Wang
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Qiyao Zhou
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Lukuan Huang
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shun'an Xu
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yingyi Fu
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Dandi Hou
- School of Marine Sciences, Ningbo University, Ningbo 315211, China.
| | - Ying Feng
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
| | - Xiaoe Yang
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
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20
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Luo Y, Zhou M, Wang F, Sheng H. Sphingomonas psychrotolerans sp. nov., isolated from root surface of Leontopodium leontopodioides in the Tianshan Mountains, Xinjiang, China. Int J Syst Evol Microbiol 2022; 72. [DOI: 10.1099/ijsem.0.005396] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A novel rod-shaped, Gram-stain-negative, aerobic bacterial strain, designated Cra20T, was isolated from the root surface of Leontopodium leontopodioides collected in the Tianshan Mountains, Xinjiang, PR China. Phylogenetic analysis based on 16S rRNA gene sequences, indicated that strain Cra20T was affiliated with the genus
Sphingomonas
, and was most closely related to
Sphingomonas gei
ZFGT-11T (99.0 %),
Sphingomonas naasensis
KIS18-15T (97.8%) and
Sphingomonas kyeonggiensis
THG-DT81T (97.2 %). The average nucleotide identity values between strain Cra20T,
S. gei
ZFGT-11T,
S. naasensis
KIS18-15T and
S. kyeonggiensis
THG-DT81T were 86.2, 84.2 and 78.2 %, respectively. The genomic DNA G+C content of strain Cra20T was 65.6 mol% (whole genome sequence), and Q-10 was the predominant ubiquinone. The major cellular fatty acids of strain Cra20T were summed feature 8 (comprising C18 : 1
ω6c and/or C18 : 1
ω7c, 67.3 %) and C14 : 0 2-OH (6.4 %). On the basis of genotypic, phenotypic and biochemical data, strain Cra20T is considered to represent a novel species of the genus
Sphingomonas
, for which the name Sphingomonas psychrotolerans sp. nov. is proposed. The type strain is Cra20T (=CGMCC 1.15510T=NBRC 112697T).
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Affiliation(s)
- Yang Luo
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, PR China
- School of Life Sciences, Shangrao Normal University, Shangrao Agricultural Technology Innovation Research Institute, Shangrao 334000, PR China
| | - Meng Zhou
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, PR China
- School of Life Sciences, Shangrao Normal University, Shangrao Agricultural Technology Innovation Research Institute, Shangrao 334000, PR China
| | - Fang Wang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, PR China
| | - Hongmei Sheng
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, PR China
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21
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Li Q, Xiang P, Zhang T, Wu Q, Bao Z, Tu W, Li L, Zhao C. The effect of phosphate mining activities on rhizosphere bacterial communities of surrounding vegetables and crops. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 821:153479. [PMID: 35092784 DOI: 10.1016/j.scitotenv.2022.153479] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 01/24/2022] [Accepted: 01/24/2022] [Indexed: 06/14/2023]
Abstract
The effects of phosphate mining on rhizosphere bacteria in surrounding vegetables and crops, including Lactuca sativa, Glycine max, and Triticum aestivum, are assessed in this study. As results, phosphate mining significantly increased the contents of some large elements, trace elements, and heavy metals in the surrounding agricultural soil, including phosphorus, magnesium, boron, cadmium, lead, arsenic, zinc, and chromium (P < 0.05). The community richness and diversity of bacteria in rhizosphere of the three crops were significantly reduced by phosphate mining (P < 0.05). Abundances of Sphingomonas and RB41 in the rhizosphere soil of phosphate mining area improved compared with the baseline in the non-phosphate mining area. Beta diversity analysis indicated that phosphate mining led to the differentiation of bacterial community structure in plant rhizospheres. Bacterial metabolic analysis indicated that different plant rhizosphere microbial flora developed various metabolic strategies in response to phosphate mining stress, including enriching unsaturated fatty acids, antibiological transport systems, cold shock proteins, etc. This study reveals the interaction between crops, rhizosphere bacteria, and soil pollutants. Select differentiated microbial strains suitable for specific plant rhizosphere environments are necessary for agricultural soil remediation. Additionally, the problem of destruction of agricultural soil and microecology caused by phosphate mining must be solved.
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Affiliation(s)
- Qiang Li
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu, Sichuan, China
| | - Peng Xiang
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu, Sichuan, China
| | - Ting Zhang
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu, Sichuan, China
| | - Qian Wu
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu, Sichuan, China
| | - Zhijie Bao
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu, Sichuan, China
| | - Wenying Tu
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu, Sichuan, China
| | - Lijiao Li
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu, Sichuan, China
| | - Changsong Zhao
- School of Public Health, Chengdu Medical College, Chengdu, Sichuan, China.
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22
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Sharma P, Chouhan R, Bakshi P, Gandhi SG, Kaur R, Sharma A, Bhardwaj R. Amelioration of Chromium-Induced Oxidative Stress by Combined Treatment of Selected Plant-Growth-Promoting Rhizobacteria and Earthworms via Modulating the Expression of Genes Related to Reactive Oxygen Species Metabolism in Brassica juncea. Front Microbiol 2022; 13:802512. [PMID: 35464947 PMCID: PMC9019754 DOI: 10.3389/fmicb.2022.802512] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 01/25/2022] [Indexed: 01/24/2023] Open
Abstract
Chromium (Cr) toxicity leads to the enhanced production of reactive oxygen species (ROS), which are extremely toxic to the plant and must be minimized to protect the plant from oxidative stress. The potential of plant-growth-promoting rhizobacteria (PGPR) and earthworms in plant growth and development has been extensively studied. The present study was aimed at investigating the effect of two PGPR (Pseudomonas aeruginosa and Burkholderia gladioli) along with earthworms (Eisenia fetida) on the antioxidant defense system in Brassica juncea seedlings under Cr stress. The Cr toxicity reduced the fresh and dry weights of seedlings, enhanced the levels of superoxide anion (O2•-), hydrogen peroxide (H2O2), malondialdehyde (MDA), and electrolyte leakage (EL), which lead to membrane as well as the nuclear damage and reduced cellular viability in B. juncea seedlings. The activities of the antioxidant enzymes, viz., superoxide dismutase (SOD), guaiacol peroxidase (POD), ascorbate peroxidase (APOX), glutathione peroxidase (GPOX), dehydroascorbate reductase (DHAR), and glutathione reductase (GR) were increased; however, a reduction was observed in the activity of catalase (CAT) in the seedlings under Cr stress. Inoculation of the PGPR and the addition of earthworms enhanced the activities of all other antioxidant enzymes except GPOX, in which a reduction of the activity was observed. For total lipid- and water-soluble antioxidants and the non-enzymatic antioxidants, viz., ascorbic acid and glutathione, an enhance accumulation was observed upon the inoculation with PGPR and earthworms. The supplementation of PGPR with earthworms (combined treatment) reduced both the reactive oxygen species (ROS) and the MDA content by modulating the defense system of the plant. The histochemical studies also corroborated that the combined application of PGPR and earthworms reduced O2•-, H2O2, lipid peroxidation, and membrane and nuclear damage and improved cell viability. The expression of key antioxidant enzyme genes, viz., SOD, CAT, POD, APOX, GR, DHAR, and GST showed the upregulation of these genes at post-transcriptional level upon the combined treatment of the PGPR and earthworms, thereby corresponding to the improved plant biomass. However, a reduced expression of RBOH1 gene was noticed in seedlings supplemented under the effect of PGPR and earthworms grown under Cr stress. The results provided sufficient evidence regarding the role of PGPR and earthworms in the amelioration of Cr-induced oxidative stress in B. juncea.
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Affiliation(s)
- Pooja Sharma
- Department of Microbiology, DAV University, Jalandhar, India.,Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, India
| | - Rekha Chouhan
- Indian Institute of Integrative Medicine (CSIR), Jammu, India
| | - Palak Bakshi
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, India
| | - Sumit G Gandhi
- Indian Institute of Integrative Medicine (CSIR), Jammu, India
| | - Rupinder Kaur
- Department of Biotechnology, DAV College, Amritsar, India
| | - Ashutosh Sharma
- Faculty of Agricultural Sciences, DAV University, Jalandhar, India
| | - Renu Bhardwaj
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, India
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23
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Effect of Fungal Endophyte Epichloë bromicola Infection on Cd Tolerance in Wild Barley ( Hordeum brevisubulatum). J Fungi (Basel) 2022; 8:jof8040366. [PMID: 35448597 PMCID: PMC9026929 DOI: 10.3390/jof8040366] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 03/24/2022] [Accepted: 03/30/2022] [Indexed: 01/17/2023] Open
Abstract
Hydroponic Hordeum brevisubulatum (wild barley) was used as material in the greenhouse to study the effects of endophyte infection on plant growth, Cd absorption and transport, subcellular distribution, and Cd chemical forms under CdCl2 stress. Endophytic fungi respond positively to chlorophyll content and photosynthetic efficiency under Cd stress. The order of Cd absorption in different parts of the plant was: roots > stems > leaves. Endophyte infection increased the plant’s absorption and transport of Cd while causing a significant difference in the stem, which was associated with the distribution density of endophyte hyphae. The proportion of organelle Cd in endophyte-infected wild barley was significantly higher, which facilitated more Cd transport to aboveground. Cd stress showed a slight effect on the chemical forms of Cd in leaves. The proportion of phosphate, oxalate, and residual Cd increased in the stem. Cd existed in the form of inorganic salt, organic acid, pectin, and protein in roots. Endophyte infection reduced the Cd content of the more toxic chemical forms to protect the normal progress of plant physiological functions. Therefore, the isolation of cell walls and vacuoles is a key mechanism for plant Cd tolerance and detoxification. As endophyte infections have more ability to absorb Cd in plants, H. brevisubulatum−Epichloë bromicola symbionts can improve heavy metal contaminated soil and water.
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24
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Gui JY, Rao S, Gou Y, Xu F, Cheng S. Comparative study of the effects of selenium yeast and sodium selenite on selenium content and nutrient quality in broccoli florets (Brassica oleracea L. var. italica). JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2022; 102:1707-1718. [PMID: 34460116 DOI: 10.1002/jsfa.11511] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 08/16/2021] [Accepted: 08/30/2021] [Indexed: 05/28/2023]
Abstract
BACKGROUND Approximately 0.5-1 billion people worldwide face the risk of selenium (Se) deficiency because of the low Se concentration in their diets. Broccoli can accumulate Se and comprises a source of daily Se supplement for humans. Se biofortification is an effective strategy for enhancing Se content in crops. In the present study, the effects of Se yeast and selenite application on the Se content and nutrient quality of broccoli were investigated. RESULTS Broccoli growth was promoted by Se yeast but inhibited by selenite. The total Se content of broccoli florets remarkably increased with increasing exogenous Se fertilizer concentrations. The main Se species in broccoli florets were methyl-selenocysteine and selenomethionine, and their contents were significantly higher under Se yeast treatments than under selenite treatments. Se(VI) was detected only under selenite treatments. Se yeast and selenite had different influences on soluble sugar, soluble protein, vitamin C and free amino acid contents in broccoli florets. The total phenolic acid and glucosinolate contents were substantially increased by Se yeast and selenite, although the total flavonoid content was reduced by Se yeast. Tests on antioxidant enzyme activities revealed that several antioxidant enzymes (catalase, peroxidase, superoxide dismutase and glutathione peroxidase) responded to Se yeast and selenite treatments. CONCLUSION Se yeast is preferred over selenite for maximizing Se uptake and nutrient accumulation in Se-rich broccoli cultivation. However, an extremely high Se content in broccoli florets cannot be directly consumed by humans, although they can be processed into Se supplements. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Jia-Ying Gui
- College of Horticulture and Gardening, Yangtze University, Jingzhou, China
| | - Shen Rao
- School of Modern Industry for Selenium Science and Engineering, National R&D Center for Se-rich Agricultural Products Processing Technology, Wuhan Polytechnic University, Wuhan, 430023, China
| | - Yuanyuan Gou
- College of Horticulture and Gardening, Yangtze University, Jingzhou, China
| | - Feng Xu
- College of Horticulture and Gardening, Yangtze University, Jingzhou, China
| | - Shuiyuan Cheng
- School of Modern Industry for Selenium Science and Engineering, National R&D Center for Se-rich Agricultural Products Processing Technology, Wuhan Polytechnic University, Wuhan, 430023, China
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25
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Wu Y, Santos SS, Vestergård M, Martín González AM, Ma L, Feng Y, Yang X. A field study reveals links between hyperaccumulating Sedum plants-associated bacterial communities and Cd/Zn uptake and translocation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 805:150400. [PMID: 34818769 DOI: 10.1016/j.scitotenv.2021.150400] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 06/13/2023]
Abstract
Hyperaccumulating ecotypes of Sedum plants are promising Cd/Zn phytoextractors, with potential for leveraging its rhizospheric or endophytic microbiomes to improve phytoremediation efficiency. However, research of bacteria associated with Sedum at field scale is still lacking. Here, we presented a detailed investigation of the bacterial microbiome of hyperaccumulating Sedum ecotypes (S. alfredii and S. plumbizincicola) and a non-hyperaccumulating S. alfredii ecotype, which grow at different soil environments. Moreover, we evaluated the heavy metal uptake and translocation potential of Sedum plants at different locations. The results showed that both HE ecotypes, contrary to the NHE, were efficient for phytoremediation in mine areas and farmlands. For NHE plants, rhizosphere co-occurrence networks were more complex than the networks of other compartments, while networks of HE plants were more complex in bulk soil and roots. The proportion of positive correlations within co-occurrence networks was higher for the HE plants, suggesting a greater potential for mutualistic interactions. Plant compartment and location predominantly shaped the microbiome assembly, and Proteobacteria, Actinobacteria and Acidobacteria dominated the bacterial communities of Sedum plants. Keystone taxa related to Zn hyperaccumulation are similar to those related to Cd hyperaccumulation, and nine bacterial genera had significantly positive correlation with Cd/Zn hyperaccumulation. Taxa, linked to phytoremediation in both mine and farmland (i.e. Actinospica and Streptomyces from Actinobacteria), could be targets for further investigation of their ability to promote metal phytoremediation of Sedum species.
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Affiliation(s)
- Yingjie Wu
- Key Laboratory of Environment Remediation and Ecological Health of Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China; Department of Agroecology, Aarhus University, Forsøgsvej 1, Slagelse, Denmark; College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Susana S Santos
- Department of Agroecology, Aarhus University, Forsøgsvej 1, Slagelse, Denmark
| | - Mette Vestergård
- Department of Agroecology, Aarhus University, Forsøgsvej 1, Slagelse, Denmark.
| | | | - Luyao Ma
- Key Laboratory of Environment Remediation and Ecological Health of Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Ying Feng
- Key Laboratory of Environment Remediation and Ecological Health of Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China.
| | - Xiaoe Yang
- Key Laboratory of Environment Remediation and Ecological Health of Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
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26
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Wang F, Wei Y, Yan T, Wang C, Chao Y, Jia M, An L, Sheng H. Sphingomonas sp. Hbc-6 alters physiological metabolism and recruits beneficial rhizosphere bacteria to improve plant growth and drought tolerance. FRONTIERS IN PLANT SCIENCE 2022; 13:1002772. [PMID: 36388485 PMCID: PMC9650444 DOI: 10.3389/fpls.2022.1002772] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 10/12/2022] [Indexed: 05/13/2023]
Abstract
Drought poses a serious threat to plant growth. Plant growth-promoting bacteria (PGPB) have great potential to improve plant nutrition, yield, and drought tolerance. Sphingomonas is an important microbiota genus that is extensively distributed in the plant or rhizosphere. However, the knowledge of its plant growth-promoting function in dry regions is extremely limited. In this study, we investigated the effects of PGPB Sphingomonas sp. Hbc-6 on maize under normal conditions and drought stress. We found that Hbc-6 increased the biomass of maize under normal conditions and drought stress. For instance, the root fresh weight and shoot dry weight of inoculated maize increased by 39.1% and 34.8% respectively compared with non-inoculated plant, while they increased by 61.3% and 96.3% respectively under drought conditions. Hbc-6 also promoted seed germination, maintained stomatal morphology and increased chlorophyll content so as to enhance photosynthesis of plants. Hbc-6 increased antioxidant enzyme (catalase, superoxide, peroxidase) activities and osmoregulation substances (proline, soluble sugar) and up-regulated the level of beneficial metabolites (resveratrol, etc.). Moreover, Hbc-6 reshaped the maize rhizosphere bacterial community, increased its richness and diversity, and made the rhizosphere bacterial community more complex to resist stress; Hbc-6 could also recruit more potentially rhizosphere beneficial bacteria which might promote plant growth together with Hbc-6 both under normal and drought stress. In short, Hbc-6 increased maize biomass and drought tolerance through the above ways. Our findings lay a foundation for exploring the complex mechanisms of interactions between Sphingomonas and plants, and it is important that Sphingomonas sp. Hbc-6 can be used as a potential biofertilizer in agricultural production, which will assist finding new solutions for improving the growth and yield of crops in arid areas.
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Affiliation(s)
- Fang Wang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Yali Wei
- Center for Terrestrial Biodiversity of the South China Sea, Hainan University, Haikou, China
| | - Taozhe Yan
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Cuicui Wang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Yinghui Chao
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Mingyue Jia
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Lizhe An
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
- The College of Forestry, Beijing Forestry University, Beijing, China
- *Correspondence: Lizhe An, ; Hongmei Sheng,
| | - Hongmei Sheng
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, China
- *Correspondence: Lizhe An, ; Hongmei Sheng,
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27
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Xiao Y, Dai MX, Zhang GQ, Yang ZX, He YM, Zhan FD. Effects of the Dark Septate Endophyte (DSE) Exophiala pisciphila on the Growth of Root Cell Wall Polysaccharides and the Cadmium Content of Zea mays L. under Cadmium Stress. J Fungi (Basel) 2021; 7:jof7121035. [PMID: 34947018 PMCID: PMC8708371 DOI: 10.3390/jof7121035] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 11/27/2021] [Accepted: 11/30/2021] [Indexed: 02/06/2023] Open
Abstract
This paper aims to investigate the mechanism by which dark septate endophytes (DSEs) enhance cadmium (Cd) tolerance in there host plants. Maize (Zea mays L.) was inoculated with a DSE, Exophiala pisciphila, under Cd stress at different concentrations (0, 5, 10, and 20 mg·kg−1). The results show that, under 20 mg/kg Cd stress, DSE significantly increased maize biomass and plant height, indicating that DSE colonization can be utilized to increase the Cd tolerance of host plants. More Cd was retained in DSE-inoculated roots, especially that fixed in the root cell wall (RCW). The capability of DSE to induce a higher Cd holding capacity in the RCW is caused by modulation of the total sugar and uronic acid of DSE-colonized RCW, mainly the pectin and hemicellulose fractions. The fourier-transform spectroscopy analysis results show that carboxyl, hydroxyl, and acidic groups are involved in Cd retention in the DSE-inoculated RCW. The promotion of the growth of maize and improvement in its tolerance to Cd due to DSEs are related to restriction of the translocation of Cd from roots to shoots; resistance of Cd uptake Cd inside cells; and the increase in RCW-integrated Cd through modulating RCW polysaccharide components.
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Pastoshchuk A, Yumyna Y, Zelena P, Nudha V, Yanovska V, Kovalenko M, Taran N, Patyka V, Skivka L. Beneficial traits of grain-residing endophytic communities in wheat with different sensitivity to Pseudomonas syringae. REGULATORY MECHANISMS IN BIOSYSTEMS 2021. [DOI: 10.15421/022168] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Deep insight into compositional and functional features of endophytic bacterial communities residing in wheat grains opens the way to the use of their plant growth promoting and biocontrol abilities in agricultural biotechnology. The aim of this work was to compare grain-residing endophytes from winter wheat varieties with different sensitivity to Pseudomonas syringae pv. atrofaciens (McCulloch) and to examine their plant-beneficial traits and antagonistic effects. Grain-residing bacteria were isolated from surface-sterilized grains of three wheat varieties sown in Ukraine following a culture-dependent protocol, and were screened for their plant growth promotion (PGP) and antagonistic properties. Bacterial morphotypes were represented by gram-negative rods, endospore-forming bacilli and gram-positive cocci. Different resistance to phytopathogenic pseudomonads was associated with distinctive quantitative and functional features of grain-residing endophytic communities. High resistance to P. syringae was coupled with the prevalence of gram-negative rods in the endophytic community, the highest proportion of endophytic bacteria possessing three PGP activities (phosphate solubilization, nitrogen fixation and production of indolic compounds) simultaneously, and with the most potent antagonistic activity of grain-residing endospore-forming bacilli. In total, five grain-residing isolates, which were obtained from three wheat varieties (two isolates from varieties with medium and high resistance and one – from a low-resistant variety), demonstrated ability to restrain P. syringae pv. atrofaciens (McCulloch) growth. Two isolates (P6 and P10) which were obtained from the high-resistant wheat variety Podolyanka and were assigned to Paenibacillus and Brevibacillus genera according to their biochemical profiling and MS-DS identification, showed the most potent antagonistic effects as indicated by maximum inhibition zone in agar well diffusion assay. These results shed light on the association of the features of grain-residing endophytic bacteria with wheat resistance to phytopathogenic pseudomonads. Isolates from the high-resistant wheat variety can be recommended for grain dressing as plant growth promoting and biocontrol agents for P. syringae pv. atrofaciens (McCulloch).
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Du Y, Zhang D, Zhou D, Liu L, Wu J, Chen H, Jin D, Yan M. The growth of plants and indigenous bacterial community were significantly affected by cadmium contamination in soil-plant system. AMB Express 2021; 11:103. [PMID: 34245386 PMCID: PMC8272791 DOI: 10.1186/s13568-021-01264-y] [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: 02/01/2021] [Accepted: 07/03/2021] [Indexed: 11/10/2022] Open
Abstract
Concentrations of heavy metals continue to increase in soil environments as a result of both anthropogenic activities and natural processes. Cadmium (Cd) is one of the most toxic heavy metals and poses health risks to both humans and the ecosystem. Herein, we explore the impacts of Cd on a soil-plant system composed of oilseed rapes (Brassica napus and Brassica juncea) and bacteria. The results showed that Cd accumulation within tissues of two species of oilseed rapes enhanced with increasing concentrations of Cd in soils, and Cd treatment decreased their chlorophyll content and suppressed rapeseeds growth. Meanwhile, Cd stress induced the changes of antioxidative enzymes activities of both B. napus and B. juncea. Response to Cd of bacterial community was similar in soil-two species of oilseed rapes system. The impact of Cd on the bacterial communities of soils was greater than bacterial communities of plants (phyllosphere and endophyte). The α-diversity of bacterial community in soils declined significantly under higher Cd concentration (30 mg/kg). In addition, soil bacterial communities composition and structure were altered in the presence of higher Cd concentration. Meanwhile, the bacterial communities of bulk soils were significantly correlated with Cd, while the variation of rhizosphere soils bacterial communities were markedly correlated with Cd and other environmental factors of both soils and plants. These results suggested that Cd could affect both the growth of plants and the indigenous bacterial community in soil-plant system, which might further change ecosystem functions in soils.
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Efficacy of Indole Acetic Acid and Exopolysaccharides-Producing Bacillus safensis Strain FN13 for Inducing Cd-Stress Tolerance and Plant Growth Promotion in Brassica juncea (L.). APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11094160] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Untreated wastewater used for irrigating crops is the major source of toxic heavy metals and other pollutants in soils. These heavy metals affect plant growth and deteriorate the quality of edible parts of growing plants. Phytohormone (IAA) and exopolysaccharides (EPS) producing plant growth-promoting rhizobacteria can reduce the toxicity of metals by stabilizing them in soil. The present experiment was conducted to evaluate the IAA and EPS-producing rhizobacterial strains for improving growth, physiology, and antioxidant activity of Brassica juncea (L.) under Cd-stress. Results showed that Cd-stress significantly decreased the growth and physiological parameters of mustard plants. Inoculation with Cd-tolerant, IAA and EPS-producing rhizobacterial strains, however, significantly retrieved the inhibitory effects of Cd-stress on mustard growth, and physiology by up regulating antioxidant enzyme activities. Higher Cd accumulation and proline content was observed in the roots and shoot tissues upon Cd-stress in mustard plants while reduced proline and Cd accumulation was recorded upon rhizobacterial strains inoculation. Maximum decrease in proline contents (12.4%) and Cd concentration in root (26.9%) and shoot (29%) in comparison to control plants was observed due to inoculation with Bacillus safensis strain FN13. The activity of antioxidant enzymes was increased due to Cd-stress; however, the inoculation with Cd-tolerant, IAA-producing rhizobacterial strains showed a non-significant impact in the case of the activity of superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT) in Brassica juncea (L.) plants under Cd-stress. Overall, Bacillus safensis strain FN13 was the most effective strain in improving the Brassica juncea (L.) growth and physiology under Cd-stress. It can be concluded, as the strain FN13 is a potential phytostabilizing biofertilizer for heavy metal contaminated soils, that it can be recommended to induce Cd-stress tolerance in crop plants.
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A Degeneration Gradient of Poplar Trees Contributes to the Taxonomic, Functional, and Resistome Diversity of Bacterial Communities in Rhizosphere Soils. Int J Mol Sci 2021; 22:ijms22073438. [PMID: 33810508 PMCID: PMC8036350 DOI: 10.3390/ijms22073438] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 03/22/2021] [Accepted: 03/23/2021] [Indexed: 12/27/2022] Open
Abstract
Bacterial communities associated with roots influence the health and nutrition of the host plant. However, the microbiome discrepancy are not well understood under different healthy conditions. Here, we tested the hypothesis that rhizosphere soil microbial diversity and function varies along a degeneration gradient of poplar, with a focus on plant growth promoting bacteria (PGPB) and antibiotic resistance genes. Comprehensive metagenomic analysis including taxonomic investigation, functional detection, and ARG (antibiotics resistance genes) annotation revealed that available potassium (AK) was correlated with microbial diversity and function. We proposed several microbes, Bradyrhizobium, Sphingomonas, Mesorhizobium, Nocardioides, Variovorax, Gemmatimonadetes, Rhizobacter, Pedosphaera, Candidatus Solibacter, Acidobacterium, and Phenylobacterium, as candidates to reflect the soil fertility and the plant health. The highest abundance of multidrug resistance genes and the four mainly microbial resistance mechanisms (antibiotic efflux, antibiotic target protection, antibiotic target alteration, and antibiotic target replacement) in healthy poplar rhizosphere, corroborated the relationship between soil fertility and microbial activity. This result suggested that healthy rhizosphere soil harbored microbes with a higher capacity and had more complex microbial interaction network to promote plant growing and reduce intracellular levels of antibiotics. Our findings suggested a correlation between the plant degeneration gradient and bacterial communities, and provided insight into the role of high-turnover microbial communities as well as potential PGPB as real-time indicators of forestry soil quality, and demonstrated the inner interaction contributed by the bacterial communities.
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Mitigation of Nickel Toxicity and Growth Promotion in Sesame through the Application of a Bacterial Endophyte and Zeolite in Nickel Contaminated Soil. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17238859. [PMID: 33260516 PMCID: PMC7730600 DOI: 10.3390/ijerph17238859] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 11/24/2020] [Accepted: 11/25/2020] [Indexed: 11/16/2022]
Abstract
Nickel (Ni) bioavailable fraction in the soil is of utmost importance because of its involvement in plant growth and environmental feedbacks. High concentrations of Ni in the soil environment, especially in the root zone, may retard plant growth that ultimately results in reduced plant biomass and yield. However, endophytic microorganisms have great potential to reduce the toxicity of Ni, especially when applied together with zeolite. The present research work was conducted to evaluate the potential effects of an endophytic bacterium Caulobacter sp. MN13 in combination with zeolite on the physiology, growth, quality, and yield of sesame plant under normal and Ni stressed soil conditions through possible reduction of Ni uptake. Surface sterilized sesame seeds were sown in pots filled with artificially Ni contaminated soil amended with zeolite. Results revealed that plant agronomic attributes such as shoot root dry weight, total number of pods, and 1000-grains weight were increased by 41, 45, 54, and 65%, respectively, over control treatment, with combined application of bacteria and zeolite in Ni contaminated soil. In comparison to control, the gaseous exchange parameters (CO2 assimilation rate, transpiration rate, stomatal- sub-stomatal conductance, chlorophyll content, and vapor pressure) were significantly enhanced by co-application of bacteria and zeolite ranging from 20 to 49% under Ni stress. Moreover, the combined utilization of bacteria and zeolite considerably improved water relations of sesame plant, in terms of relative water content (RWC) and relative membrane permeability (RMP) along with improvement in biochemical components (protein, ash, crude fiber, fat), and micronutrients in normal as well as in Ni contaminated soil. Moreover, the same treatment modulated the Ni-stress in plants through improvement in antioxidant enzymes (AEs) activities along with improved Ni concentration in the soil and different plant tissues. Correlation and principal component analysis (PCA) further revealed that combined application of metal-tolerant bacterium Caulobacter sp. MN13 and zeolite is the most influential strategy in alleviating Ni-induced stress and subsequent improvement in growth, yield, and physio-biochemical attributes of sesame plant.
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Wu Y, Ma L, Liu Q, Vestergård M, Topalovic O, Wang Q, Zhou Q, Huang L, Yang X, Feng Y. The plant-growth promoting bacteria promote cadmium uptake by inducing a hormonal crosstalk and lateral root formation in a hyperaccumulator plant Sedum alfredii. JOURNAL OF HAZARDOUS MATERIALS 2020; 395:122661. [PMID: 32305720 DOI: 10.1016/j.jhazmat.2020.122661] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 03/17/2020] [Accepted: 04/04/2020] [Indexed: 05/27/2023]
Abstract
Plant growth-promoting bacteria (PGPB) that inhabit hyperaccumulating plants assist cadmium (Cd) absorption, but the underlying mechanism has not been comprehensively studied. For this reason, we combined the fluorescence imaging, and transcriptomic and metabolomic methods in a Cd hyperaccumulator, Sedum alfredii, inoculated or not with PGPB Pseudomonas fluorescens. The results showed that the newly emerged lateral roots, that were heavily colonized by P. fluorescens, are the main entry for Cd influx in S. alfredii. Inoculation with P. fluorescens promoted a lateral root formation of its host plant, leading to a higher Cd phytoremediation efficiency. Furthermore, the plant transcriptome revealed that 146 plant hormone related genes were significantly up-regulated by the bacterial inoculation, with 119 of them showing a complex interaction, which suggests that a hormonal crosstalk participated root development. The targeted metabolomics analysis showed that P. fluorescens inoculation significantly increased indole acetic acid concentration and significantly decreased concentrations of abscisic acid, brassinolide, trans-zeatin, ethylene and jasmonic acid in S. alfredii roots, thereby inducing lateral root emergence. Altogether, our results highlight the importance of PGPB-induced lateral root formation for the increased Cd uptake in a hyperaccumulating plant.
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Affiliation(s)
- Yingjie Wu
- Key Laboratory of Environment Remediation and Ecological Health of Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Department of Agroecology, Faculty of Technical Sciences, Aarhus University, Forsøgsvej 1, 4200, Slagelse, Denmark
| | - Luyao Ma
- Key Laboratory of Environment Remediation and Ecological Health of Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Qizhen Liu
- Key Laboratory of Environment Remediation and Ecological Health of Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Mette Vestergård
- Department of Agroecology, Faculty of Technical Sciences, Aarhus University, Forsøgsvej 1, 4200, Slagelse, Denmark
| | - Olivera Topalovic
- Department of Agroecology, Faculty of Technical Sciences, Aarhus University, Forsøgsvej 1, 4200, Slagelse, Denmark
| | - Qiong Wang
- Key Laboratory of Environment Remediation and Ecological Health of Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Qiyao Zhou
- Key Laboratory of Environment Remediation and Ecological Health of Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Lukuan Huang
- Key Laboratory of Environment Remediation and Ecological Health of Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xiaoe Yang
- Key Laboratory of Environment Remediation and Ecological Health of Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Ying Feng
- Key Laboratory of Environment Remediation and Ecological Health of Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
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