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Jian L, Bai X, Zhang H, Song X, Li Z. Promotion of growth and metal accumulation of alfalfa by coinoculation with Sinorhizobium and Agrobacterium under copper and zinc stress. PeerJ 2019; 7:e6875. [PMID: 31119081 PMCID: PMC6510217 DOI: 10.7717/peerj.6875] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 03/28/2019] [Indexed: 12/31/2022] Open
Abstract
The Legume-Rhizobium symbiosis has been proposed as a promising technique for the phytoremediation of contaminated soils due to its beneficial activity in symbiotic nitrogen fixation. However, numerous studies have shown that excessive heavy metals reduce the efficiency of symbiotic nodulation with Rhizobium and inhibit plant growth. In this study, we aimed to evaluate the synergistic effects of IAA-producing bacteria and Rhizobium on Medicago lupulina growth under Cu and Zn stress. Pot experiments showed that 400 mg kg-1 Cu2 + and Zn2 + greatly inhibited plant growth, but dual inoculation of Medicago lupulina with Sinorhizobium meliloti CCNWSX0020 and Agrobacterium tumefaciens CCNWGS0286 significantly increased the number of nodules and plant biomass by enhancing antioxidant activities. Under double stress of 400 mg kg-1 Cu2 + and Zn2 +, the nodule number and nitrogenase activities of dual-inoculated plants were 48.5% and 154.4% higher, respectively, than those of plants inoculated with Sinorhizobium meliloti. The root and above-ground portion lengths of the dual-inoculated plants were 32.6% and 14.1% greater, respectively, than those of the control, while the root and above-ground portion dry weights were 34.3% and 32.2% greater, respectively, than those of the control. Compared with S. meliloti and A. tumefaciens single inoculation, coinoculation increased total Cu uptake by 39.1% and 47.5% and increased total Zn uptake by 35.4% and 44.2%, respectively, under double metal stress conditions. Therefore, coinoculation with Sinorhizobium meliloti and Agrobacterium tumefaciens enhances metal phytoextraction by increasing plant growth and antioxidant activities under Cu/Zn stress, which provides a new approach for bioremediation in heavy metal-contaminated soil.
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Affiliation(s)
- Liru Jian
- State Key Laboratory of Crop Stress Biology in Arid Areas, Northwest A&F University, Yangling, Shaanxi, China
| | - Xiaoli Bai
- Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Science, Northwest A&F University, Yangling, Shaanxi, China
| | - Hui Zhang
- Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Science, Northwest A&F University, Yangling, Shaanxi, China
| | - Xiuyong Song
- Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Science, Northwest A&F University, Yangling, Shaanxi, China
| | - Zhefei Li
- Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Science, Northwest A&F University, Yangling, Shaanxi, China
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Saadani O, Jebara SH, Fatnassi IC, Chiboub M, Mannai K, Zarrad I, Jebara M. Effect of Vicia faba L. var. minor and Sulla coronaria (L.) Medik associated with plant growth-promoting bacteria on lettuce cropping system and heavy metal phytoremediation under field conditions. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:8125-8135. [PMID: 30693447 DOI: 10.1007/s11356-019-04302-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 01/22/2019] [Indexed: 06/09/2023]
Abstract
Researches involving the use of association between legumes and PGPBs (plant growth-promoting bacteria) in heavy metal phytoremediation process were mainly performed for soils highly contaminated. However, even in agriculture soils, with moderate or low contamination levels, plants can accumulate high rates of heavy metals. So, food chain contamination by these metals presents a real threat to animal and human health. This work aimed to evaluate the use of two legumes/PGPB symbioses; Vicia faba var. minor and Sulla coronaria have been inoculated with specific heavy metal-resistant inocula in a crop rotation system with Lactuca sativa as a following crop, in order to assess their effects on soil fertility, lettuce yield, and heavy metal content. Our results showed that legume inoculation significantly enhanced their biomass production, nitrogen and phosphorus content. The use of our symbioses as green manure before lettuce cultivation, as a rotation cropping system, affected positively soil fertility. In fact, we recorded a higher organic matter content, with rapid decomposition in the soil of inoculated plots. Besides, results demonstrated a greater nitrogen and phosphorus content in this soil, especially in the plot cultivated with inoculated V. faba var. minor. The improvement of soil fertility enhanced lettuce yield and its nitrogen and phosphorus content. Moreover, inoculated legumes extracted and accumulated more heavy metals than non-inoculated legumes. Our symbioses play the role of organic trap for heavy metals, making them unavailable for following crops. These facts were supported by lettuce heavy metal content, showing a significant decrease in metal accumulation, mainly zinc and cadmium, in edible parts. Results showed the usefulness of the studied symbioses, as a main part of a rotation system with lettuce. Our symbioses can be suggested for agriculture soil phytoremediation, aiming to enhance non-legume crop yield and limit heavy metal translocation to food chain.
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Affiliation(s)
- Omar Saadani
- Centre Biotechnology Borj Cedria, University Tunis El Manar, BP 901, 2050, Hammam-Lif, Tunisia
| | - Salwa Harzalli Jebara
- Centre Biotechnology Borj Cedria, University Tunis El Manar, BP 901, 2050, Hammam-Lif, Tunisia
| | | | - Manel Chiboub
- Centre Biotechnology Borj Cedria, University Tunis El Manar, BP 901, 2050, Hammam-Lif, Tunisia
| | - Khediri Mannai
- Centre Biotechnology Borj Cedria, University Tunis El Manar, BP 901, 2050, Hammam-Lif, Tunisia
| | - Imen Zarrad
- Regional Office of Agriculture Development of Monastir, Avenue du Golf Arabe, 5000, Monastir, Tunisia
| | - Moez Jebara
- Centre Biotechnology Borj Cedria, University Tunis El Manar, BP 901, 2050, Hammam-Lif, Tunisia.
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Ren CG, Kong CC, Wang SX, Xie ZH. Enhanced phytoremediation of uranium-contaminated soils by arbuscular mycorrhiza and rhizobium. CHEMOSPHERE 2019; 217:773-779. [PMID: 30448757 DOI: 10.1016/j.chemosphere.2018.11.085] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 10/31/2018] [Accepted: 11/12/2018] [Indexed: 05/10/2023]
Abstract
Uranium phytoextraction is a promising technology, however, facing difficult that limited plant biomass due to nutrient deficiency in the contaminated sites. The aim of this study is to evaluate the potential of a symbiotic associations of a legume Sesbania rostrata, rhizobia and arbuscular mycorrhiza fungi (AMF) for reclamation of uranium contaminated soils. Results showed AMF and rhizobia had a mutual beneficial relations in the triple symbiosis, which significantly increased plant biomass and uranium accumulation in S. rostrata plant. The highest uranium removal rates was observed in plant-AMF-rhizobia treated soils, in which 50.5-73.2% had been extracted, whereas 7.2-23.3% had been extracted in plant-treated soil. Also, the S. rostrata phytochelatin synthase (PCS) genes expression were increased in AMF and rhizobia plants compared with the plants. Meantime, content of malic acid, succinic acid and citric acid were elevated in S. rostrata root exudates of AMF and rhizobia inoculated plants. The facts suggest that the mutual interactions in the triple symbiosis help to improve phytoremediation efficiency of uranium by S. rostrata.
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Affiliation(s)
- Cheng-Gang Ren
- Key Laboratory of Biology and Utilization of Biological Resources of Coastal Zone, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China
| | - Cun-Cui Kong
- College of Marine Life Sciences, Ocean University of China, Qingdao, PR China
| | - Shuo-Xiang Wang
- Key Laboratory of Biology and Utilization of Biological Resources of Coastal Zone, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China
| | - Zhi-Hong Xie
- Key Laboratory of Biology and Utilization of Biological Resources of Coastal Zone, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China.
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Stambulska UY, Bayliak MM. Legume-Rhizobium Symbiosis: Secondary Metabolites, Free Radical Processes, and Effects of Heavy Metals. BIOACTIVE MOLECULES IN FOOD 2019. [DOI: 10.1007/978-3-319-76887-8_43-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Singh S, Kumar V, Sidhu GK, Datta S, Dhanjal DS, Koul B, Janeja HS, Singh J. Plant growth promoting rhizobacteria from heavy metal contaminated soil promote growth attributes of Pisum sativum L. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2019. [DOI: 10.1016/j.bcab.2019.01.035] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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56
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Fan M, Liu Z, Nan L, Wang E, Chen W, Lin Y, Wei G. Isolation, characterization, and selection of heavy metal-resistant and plant growth-promoting endophytic bacteria from root nodules of Robinia pseudoacacia in a Pb/Zn mining area. Microbiol Res 2018; 217:51-59. [DOI: 10.1016/j.micres.2018.09.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Revised: 08/14/2018] [Accepted: 09/05/2018] [Indexed: 11/26/2022]
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Baig MA, Ahmad J, Bagheri R, Ali AA, Al-Huqail AA, Ibrahim MM, Qureshi MI. Proteomic and ecophysiological responses of soybean (Glycine max L.) root nodules to Pb and hg stress. BMC PLANT BIOLOGY 2018; 18:283. [PMID: 30428829 PMCID: PMC6237034 DOI: 10.1186/s12870-018-1499-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 10/25/2018] [Indexed: 05/19/2023]
Abstract
BACKGROUND Lead (Pb) and mercury (Hg) are persistent hazardous metals in industrially polluted soils which can be toxic in low quantities. Metal toxicity can cause changes at cellular and molecular level which should be studied for better understanding of tolerance mechanism in plants. Soybean (Glycine max L.) is an important oilseed crop of the world including India. Indian soils growing soybean are often contaminated by Pb and Hg. The aim of this study was to explore how soybean root nodule responds to Pb and Hg through proteomic and ecophysiological alterations in order to enhance tolerance to metal stress. RESULTS Soybean plants were exposed to Pb (30 ppm PbCl2) and Hg (0.5 ppm HgCl2) to study histological, histochemical, biochemical and molecular response of N2-fixing symbiotic nodules. Both Pb and Hg treatment increased the level of oxidative stress in leaves and nodules. Chlorosis in leaves and morphological/anatomical changes in nodules were observed. Activities of ascorbate peroxidase, glutathione reductase and catalase were also modulated. Significant changes were observed in abundance of 76 proteins by Pb and Hg. Pb and Hg influenced abundance of 33 proteins (17 up and 16 down) and 43 proteins (33 up and 10 down), respectively. MS/MS ion search identified 55 proteins which were functionally associated with numerous cellular functions. Six crucial proteins namely catalase (CAT), allene oxide synthase (AOS), glutathione S-transferase (GST), calcineurin B like (CBL), calmodulin like (CML) and rapid alkalinisation factor (RAF) were selected for transcript abundance estimation. The qRT-PCR based real time expression exhibited a positive correlation with proteomics expression except for GST and RAF. CONCLUSION Soybean root nodule responds to metal stress by increased abundance of defence, development and repair related proteins. An efficient proteomic modulation might lead to metal-induced stress tolerance in N2-fixing nodules. Although concentrations of Pb and Hg used in the study cannot be considered equimolar, yet Hg seems to induce more changes in nodule proteomic profile, and higher damage to both bacteroides and root anatomy.
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Affiliation(s)
- Mohd Affan Baig
- Proteomics and Bioinformatics Lab, Department of Biotechnology, Jamia Millia Islamia (A Central University), New Delhi, 110025 India
| | - Javed Ahmad
- Proteomics and Bioinformatics Lab, Department of Biotechnology, Jamia Millia Islamia (A Central University), New Delhi, 110025 India
| | - Rita Bagheri
- Proteomics and Bioinformatics Lab, Department of Biotechnology, Jamia Millia Islamia (A Central University), New Delhi, 110025 India
| | - Arlene Asthana Ali
- Proteomics and Bioinformatics Lab, Department of Biotechnology, Jamia Millia Islamia (A Central University), New Delhi, 110025 India
| | - Asma Abdulkareem Al-Huqail
- Department of Botany and Microbiology, Science College, King Saud University, 11495, Riyadh, Saudi Arabia
| | - Mohamed Mohamed Ibrahim
- Department of Botany and Microbiology, Faculty of Science, Alexandria University, P.O. Box 21511, Alexandria, Egypt
| | - Mohammad Irfan Qureshi
- Proteomics and Bioinformatics Lab, Department of Biotechnology, Jamia Millia Islamia (A Central University), New Delhi, 110025 India
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Fagorzi C, Checcucci A, diCenzo GC, Debiec-Andrzejewska K, Dziewit L, Pini F, Mengoni A. Harnessing Rhizobia to Improve Heavy-Metal Phytoremediation by Legumes. Genes (Basel) 2018; 9:genes9110542. [PMID: 30413093 PMCID: PMC6266702 DOI: 10.3390/genes9110542] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 11/05/2018] [Accepted: 11/06/2018] [Indexed: 12/15/2022] Open
Abstract
Rhizobia are bacteria that can form symbiotic associations with plants of the Fabaceae family, during which they reduce atmospheric di-nitrogen to ammonia. The symbiosis between rhizobia and leguminous plants is a fundamental contributor to nitrogen cycling in natural and agricultural ecosystems. Rhizobial microsymbionts are a major reason why legumes can colonize marginal lands and nitrogen-deficient soils. Several leguminous species have been found in metal-contaminated areas, and they often harbor metal-tolerant rhizobia. In recent years, there have been numerous efforts and discoveries related to the genetic determinants of metal resistance by rhizobia, and on the effectiveness of such rhizobia to increase the metal tolerance of host plants. Here, we review the main findings on the metal resistance of rhizobia: the physiological role, evolution, and genetic determinants, and the potential to use native and genetically-manipulated rhizobia as inoculants for legumes in phytoremediation practices.
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Affiliation(s)
- Camilla Fagorzi
- Department of Biology, University of Florence, Via Madonna del Piano 6, 50019 Sesto Fiorentino, Italy.
| | - Alice Checcucci
- Department of Biology, University of Florence, Via Madonna del Piano 6, 50019 Sesto Fiorentino, Italy.
| | - George C diCenzo
- Department of Biology, University of Florence, Via Madonna del Piano 6, 50019 Sesto Fiorentino, Italy.
| | - Klaudia Debiec-Andrzejewska
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
| | - Lukasz Dziewit
- Department of Bacterial Genetics, Institute of Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
| | - Francesco Pini
- Department of Agri-food Production and Environmental Science, University of Florence, 50144 Florence, Italy.
| | - Alessio Mengoni
- Department of Biology, University of Florence, Via Madonna del Piano 6, 50019 Sesto Fiorentino, Italy.
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Chen J, Liu YQ, Yan XW, Wei GH, Zhang JH, Fang LC. Rhizobium inoculation enhances copper tolerance by affecting copper uptake and regulating the ascorbate-glutathione cycle and phytochelatin biosynthesis-related gene expression in Medicago sativa seedlings. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 162:312-323. [PMID: 30005404 DOI: 10.1016/j.ecoenv.2018.07.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 06/12/2018] [Accepted: 07/01/2018] [Indexed: 05/13/2023]
Abstract
Despite numerous reports that legume-rhizobium symbiosis alleviates Cu stress in plants, the possible roles of legume-rhizobium symbiosis and the regulatory mechanisms in counteracting Cu toxicity remain unclear. Here, Sinorhizobium meliloti CCNWSX0020 was used for analyzing the effects of rhizobium inoculation on plant growth in Medicago sativa seedlings under Cu stress. Our results showed that rhizobium inoculation alleviated Cu-induced growth inhibition, and increased nitrogen concentration in M. sativa seedlings. Moreover, the total amount of Cu uptake in inoculated plants was significantly increased compared with non-inoculated plants, and the increase in the roots was much higher than that in the shoots, thus decreasing the transfer coefficient and promoting Cu phytostabilization. Cu stress induced lipid peroxidation and reactive oxygen species production, but rhizobium inoculation reduced these components' accumulation through altering antioxidant enzyme activities and regulating ascorbate-glutathione cycles. Furthermore, legume-rhizobium symbiosis regulated the gene expression involved in antioxidant responses, phytochelatin (PC) biosynthesis, and metallothionein biosynthesis in M. sativa seedlings under Cu stress. Our results demonstrate that rhizobium inoculation enhanced Cu tolerance by affecting Cu uptake, regulating antioxidant enzyme activities and the ascorbate-glutathione cycle, and influencing PC biosynthesis-related gene expression in M. sativa. The results provide an efficient strategy for phytoremediation of Cu-contaminated soils.
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Affiliation(s)
- Juan Chen
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, Shaanxi 712100, PR China; School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong
| | - Yu-Qing Liu
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Xiao-Wu Yan
- School of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Ge-Hong Wei
- School of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Jian-Hua Zhang
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong; Department of Biology, Hong Kong Baptist University, Hong Kong
| | - Lin-Chuan Fang
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, Shaanxi 712100, PR China.
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Heavy metal accumulation in Lathyrus sativus growing in contaminated soils and identification of symbiotic resistant bacteria. Arch Microbiol 2018; 201:107-121. [PMID: 30276423 DOI: 10.1007/s00203-018-1581-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 07/24/2018] [Accepted: 09/28/2018] [Indexed: 02/06/2023]
Abstract
In this study, two populations of leguminous plants Lathyrus sativus were grown in four soils that were collected from sites differently contaminated by heavy metals. Evaluations included basic soil properties, concentrations of major nutrients and four metals (copper, zinc, lead and cadmium) in these soils. Investigation of Lathyrus sativus response to contamination showed that the increase of heavy metal concentration in soils affected biomass of plant, number of nodules and plant metal uptake. Heavy metal tolerance of 46 isolated bacteria from the root nodules was evaluated and demonstrated that the maximum concentration of Cd, Pb, Cu and Zn tolerated by strains were 0.8, 2.5, 0.2, and 0.5 mM, respectively. Twenty-two isolates were tested for their effects on plant biomass production and nodule formation and showed that only R. leguminosarum nodulated Lathyrus sativus, while some bacteria improved the shoot and root dry biomass. Sequences of their 16S rDNA gene fragments were also obtained and evaluated for tentative identification of the isolates which revealed different bacterial genera represented by Rhizobium sp, Rhizobium leguminosarum, Sinorhizobium meliloti, Pseudomonas sp, Pseudomonas fluorescens, Luteibacter sp, Variovorax sp, Bacillus simplex and Bacillus megaterium. The existence of Pb- and Cd-resistant genes (PbrA and CadA) in these bacteria was determined by PCR, and it showed high homology with PbrA and CadA genes from other bacteria. The tested resistant population was able to accumulate high concentrations of Pb and Cd in all plant parts and, therefore, can be classified as a strong metal accumulator with suitable potential for phytoremediation of Pb and Cd polluted sites. Heavy metal resistant and efficient bacteria isolated from root nodules were chosen with Lathyrus sativus to form symbiotic associations for eventual bioremediation program, which could be tested to remove pollutants from contaminated sites.
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Abdelkrim S, Jebara SH, Saadani O, Jebara M. Potential of efficient and resistant plant growth-promoting rhizobacteria in lead uptake and plant defence stimulation in Lathyrus sativus under lead stress. PLANT BIOLOGY (STUTTGART, GERMANY) 2018; 20:857-869. [PMID: 29907996 DOI: 10.1111/plb.12863] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 05/08/2018] [Accepted: 06/12/2018] [Indexed: 06/08/2023]
Abstract
The ability of plant growth-promoting rhizobacteria (PGPR) to enhance Lathyrus sativus tolerance to lead (Pb) stress was investigated. Ten consortia formed by mixing four efficient and Pb-resistant PGPR strains were assessed for their beneficial effect in improving Pb (0.5 mM) uptake and in inducing the host defence system of L. sativus under hydroponic conditions based on various physiological and biochemical parameters. Lead stress significantly decreased shoot (SDW) and root (RDW) dry weight, but PGPR inoculation improved both dry weights, with highest increases in SDW and RDW of plants inoculated with I5 (R. leguminosarum (M5) + P. fluorescens (K23) + Luteibacter sp. + Variovorax sp.) and I9 (R. leguminosarum (M5) + Variovorax sp. + Luteibacter sp. + S. meliloti) by 151% and 94%, respectively. Additionally, inoculation significantly enhanced both chlorophyll and soluble sugar content, mainly in I5 inoculated leaves by 238% and 71%, respectively, despite the fact that Pb decreased these parameters. We also found that PGPR inoculation helps to reduce oxidative damage and enhances antioxidant enzyme activity, phenolic compound biosynthesis, carotenoids and proline content. PGPR inoculation increased Pb uptake in L. sativus, with highest increase in shoots of plants inoculated with I5 and I7, and in roots and nodules of plants inoculated with I1. Moreover, PGPR inoculation enhanced mineral homeostasis for Ca, Cu and Zn under Pb stress, mainly in plants inoculated with I1, I5, I7 and I9. Results of our study suggest the potential of efficient and Pb-resistant PGPR in alleviating harmful effects of metal stress via activation of various defence mechanisms and enhancing Pb uptake that promotes tolerance of L. sativus to Pb stress.
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Affiliation(s)
- S Abdelkrim
- Laboratory of Legumes, Center of Biotechnology of Borj Cedria, Hammam Lif, Tunisia
- National Agronomic Institute of Tunisia, University of Carthage, Tunis, Tunisia
| | - S H Jebara
- Laboratory of Legumes, Center of Biotechnology of Borj Cedria, Hammam Lif, Tunisia
| | - O Saadani
- Laboratory of Legumes, Center of Biotechnology of Borj Cedria, Hammam Lif, Tunisia
| | - M Jebara
- Laboratory of Legumes, Center of Biotechnology of Borj Cedria, Hammam Lif, Tunisia
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Sujkowska-Rybkowska M, Ważny R. Metal resistant rhizobia and ultrastructure of Anthyllis vulneraria nodules from zinc and lead contaminated tailing in Poland. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2018; 20:709-720. [PMID: 29723046 DOI: 10.1080/15226514.2017.1413336] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
This present paper studies the response of Anthyllis vulneraria-Rhizobium symbiosis to heavy metal stress. The symbiotic rhizobium bacteria isolated from root nodules of A. vulneraria from zinc and lead wastes were examined in this project. Light microscopy (LM) and transmission electron microscopy (TEM) were used to analyze the nodule anatomy and ultrastructure and conduct a comparison with nonmetal-treated nodules. 16S ribosomal DNA sequence analysis of bacteria isolated from metal-treated nodules revealed the presence of Rhizobium metallidurans and Bradyrhizobium sp. In regard to heavy metal resistance/tolerance, a similar tolerance to Pb was shown by both strains, and a high tolerance to Zn and a lower tolerance to Cd and Cu by R. metallidurans, whereas a high tolerance to Cd and Cu and a lower tolerance to Zn by Bradyrhizobium were found. The nodules of Anthyllis from metal-polluted tailing sites were identified as the typical determinate type of nodules. Observed under TEM microscopy changes in nodules ultrastructure like: (1) wall thickening; (2) infection thread reduction; (3) vacuole shrinkage; (4) synthesis of phenolics in vacuoles; (5) various differentiation of bacteroids and (6) simultaneous symbiosis with arbuscular mycorrhiza fungi could be considered as a form of the A.vulneraria-Rhizobium symbiosis adaptation to metal stress.
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Affiliation(s)
| | - Rafał Ważny
- b Małopolska Centre of Biotechnology, Jagiellonian University , Kraków , Poland
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63
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Abdelkrim S, Jebara SH, Saadani O, Chiboub M, Abid G, Jebara M. Effect of Pb-resistant plant growth-promoting rhizobacteria inoculation on growth and lead uptake by Lathyrus sativus. J Basic Microbiol 2018; 58:579-589. [DOI: 10.1002/jobm.201700626] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 03/02/2018] [Accepted: 04/20/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Souhir Abdelkrim
- Center of Biotechnology of Borj Cedria; Laboratory of Legumes; Hammam Lif Tunisia
- National Agronomic Institute of Tunisia; University of Carthage; Tunis Tunisia
| | - Salwa H. Jebara
- Center of Biotechnology of Borj Cedria; Laboratory of Legumes; Hammam Lif Tunisia
| | - Omar Saadani
- Center of Biotechnology of Borj Cedria; Laboratory of Legumes; Hammam Lif Tunisia
| | - Manel Chiboub
- Center of Biotechnology of Borj Cedria; Laboratory of Legumes; Hammam Lif Tunisia
| | - Ghassen Abid
- Center of Biotechnology of Borj Cedria; Laboratory of Legumes; Hammam Lif Tunisia
| | - Moez Jebara
- Center of Biotechnology of Borj Cedria; Laboratory of Legumes; Hammam Lif Tunisia
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Chromium(VI) Toxicity in Legume Plants: Modulation Effects of Rhizobial Symbiosis. BIOMED RESEARCH INTERNATIONAL 2018; 2018:8031213. [PMID: 29662899 PMCID: PMC5832134 DOI: 10.1155/2018/8031213] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 12/31/2017] [Indexed: 11/18/2022]
Abstract
Most legume species have the ability to establish a symbiotic relationship with soil nitrogen-fixing rhizobacteria that promote plant growth and productivity. There is an increasing evidence of reactive oxygen species (ROS) important role in formation of legume-rhizobium symbiosis and nodule functioning. Environmental pollutants such as chromium compounds can cause damage to rhizobia, legumes, and their symbiosis. In plants, toxic effects of chromium(VI) compounds are associated with the increased production of ROS and oxidative stress development as well as with inhibition of pigment synthesis and modification of virtually all cellular components. These metabolic changes result in inhibition of seed germination and seedling development as well as reduction of plant biomass and crop yield. However, if plants establish symbiosis with rhizobia, heavy metals are accumulated preferentially in nodules decreasing the toxicity of metals to the host plant. This review summarizes data on toxic effects of chromium on legume plants and legume-rhizobium symbiosis. In addition, we discussed the role of oxidative stress in both chromium toxicity and formation of rhizobial symbiosis and use of nodule bacteria for minimizing toxic effects of chromium on plants.
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Chiboub M, Jebara SH, Saadani O, Fatnassi IC, Abdelkerim S, Jebara M. Physiological responses and antioxidant enzyme changes in Sulla coronaria inoculated by cadmium resistant bacteria. JOURNAL OF PLANT RESEARCH 2018; 131:99-110. [PMID: 28808815 DOI: 10.1007/s10265-017-0971-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 06/16/2017] [Indexed: 06/07/2023]
Abstract
Plant growth promoting bacteria (PGPB) may help to reduce the toxicity of heavy metals on plants growing in polluted soils. In this work, Sulla coronaria inoculated with four Cd resistant bacteria (two Pseudomonas spp. and two Rhizobium sullae) were cultivated in hydroponic conditions treated by Cd; long time treatment 50 µM CdCl2 for 30 days and short time treatment; 100 µM CdCl2 for 7 days. Results showed that inoculation with Cd resistant PGPB enhanced plant biomass, thus shoot and root dry weights of control plants were enhanced by 148 and 35% respectively after 7 days. Co-inoculation of plants treated with 50 and 100 µM Cd increased plant biomasses as compared to Cd-treated and uninoculated plants. Cadmium treatment induced lipid peroxidation in plant tissues measured through MDA content in short 7 days 100 µM treatment. Antioxidant enzyme studies showed that inoculation of control plants enhanced APX, SOD and CAT activities after 30 days in shoots and SOD, APX, SOD, GPOX in roots. Application of 50 µM CdCl2 stimulated all enzymes in shoots and decreased SOD and CAT activities in roots. Moreover, 100 µM of CdCl2 increased SOD, APX, CAT and GPOX activities in shoots and increased significantly CAT activity in roots. Metal accumulation depended on Cd concentration, plant organ and time of treatment. Furthermore, the inoculation enhanced Cd uptake in roots by 20% in all treatments. The cultivation of this symbiosis in Cd contaminated soil or in heavy metal hydroponically treated medium, showed that inoculation improved plant biomass and increased Cd uptake especially in roots. Therefore, the present study established that co-inoculation of S. coronaria by a specific consortium of heavy metal resistant PGPB formed a symbiotic system useful for soil phytostabilization.
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Affiliation(s)
- Manel Chiboub
- Laboratoire des Légumineuses, Centre de Biotechnologie Borj Cedria, University Tunis El Manar, BP 901, 2050, Hammam Lif, Tunisia
| | - Salwa Harzalli Jebara
- Laboratoire des Légumineuses, Centre de Biotechnologie Borj Cedria, University Tunis El Manar, BP 901, 2050, Hammam Lif, Tunisia.
| | - Omar Saadani
- Laboratoire des Légumineuses, Centre de Biotechnologie Borj Cedria, University Tunis El Manar, BP 901, 2050, Hammam Lif, Tunisia
| | - Imen Challougui Fatnassi
- Laboratoire des Légumineuses, Centre de Biotechnologie Borj Cedria, University Tunis El Manar, BP 901, 2050, Hammam Lif, Tunisia
| | - Souhir Abdelkerim
- Laboratoire des Légumineuses, Centre de Biotechnologie Borj Cedria, University Tunis El Manar, BP 901, 2050, Hammam Lif, Tunisia
| | - Moez Jebara
- Laboratoire des Légumineuses, Centre de Biotechnologie Borj Cedria, University Tunis El Manar, BP 901, 2050, Hammam Lif, Tunisia
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Modified microplate method for rapid and efficient estimation of siderophore produced by bacteria. 3 Biotech 2017; 7:381. [PMID: 29109926 PMCID: PMC5658296 DOI: 10.1007/s13205-017-1008-y] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 10/09/2017] [Indexed: 12/20/2022] Open
Abstract
In this study, siderophore production by various bacteria amongst the plant-growth-promoting rhizobacteria was quantified by a rapid and efficient method. In total, 23 siderophore-producing bacterial isolates/strains were taken to estimate their siderophore-producing ability by the standard method (chrome azurol sulphonate assay) as well as 96 well microplate method. Production of siderophore was estimated in percent siderophore unit by both the methods. It was observed that data obtained by both methods correlated positively with each other proving the correctness of microplate method. By the modified microplate method, siderophore production by several bacterial strains can be estimated both qualitatively and quantitatively at one go, saving time, chemicals, making it very less tedious, and also being cheaper in comparison with the method currently in use. The modified microtiter plate method as proposed here makes it far easier to screen the plant-growth-promoting character of plant-associated bacteria.
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Rangel WDM, de Oliveira Longatti SM, Ferreira PAA, Bonaldi DS, Guimarães AA, Thijs S, Weyens N, Vangronsveld J, Moreira FMS. Leguminosae native nodulating bacteria from a gold mine As-contaminated soil: Multi-resistance to trace elements, and possible role in plant growth and mineral nutrition. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2017; 19:925-936. [PMID: 28323446 DOI: 10.1080/15226514.2017.1303812] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Efficient N2-fixing Leguminosae nodulating bacteria resistant to As may facilitate plant growth on As-contaminated sites. In order to identify bacteria holding these features, 24 strains were isolated from nodules of the trap species Crotalaria spectabilis (12) and Stizolobium aterrimum (12) growing on an As-contaminated gold mine site. 16S rRNA gene sequencing revealed that most of the strains belonged to the group of α-Proteobacteria, being representatives of the genera Bradyrhizobium, Rhizobium, Inquilinus, Labrys, Bosea, Starkeya, and Methylobacterium. Strains of the first four genera showed symbiotic efficiency with their original host, and demonstrated in vitro specific plant-growth-promoting (PGP) traits (production of organic acids, indole-3-acetic-acid and siderophores, 1-aminocyclopropane-1-carboxylate deaminase activity, and Ca3(PO4)2 solubilization), and increased resistance to As, Zn, and Cd. In addition, these strains and some type and reference rhizobia strains exhibited a wide resistance spectrum to β-lactam antibiotics. Both intrinsic PGP abilities and multi-element resistance of rhizobia are promising for exploiting the symbiosis with different legume plants on trace-element-contaminated soils.
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Affiliation(s)
- Wesley de M Rangel
- a Biology Department , Federal University of Lavras (UFLA) , Lavras , Minas Gerais , Brazil
- b Soil Science Department , UFLA , Lavras , Minas Gerais , Brazil
- c Soil Department , Federal University of Santa Maria (UFSM) , Santa Maria , Rio Grande do Sul , Brazil
| | | | - Paulo A A Ferreira
- b Soil Science Department , UFLA , Lavras , Minas Gerais , Brazil
- c Soil Department , Federal University of Santa Maria (UFSM) , Santa Maria , Rio Grande do Sul , Brazil
| | - Daiane S Bonaldi
- b Soil Science Department , UFLA , Lavras , Minas Gerais , Brazil
| | | | - Sofie Thijs
- d Centre for Environmental Sciences, Hasselt University , Diepenbeek , Belgium
| | - Nele Weyens
- d Centre for Environmental Sciences, Hasselt University , Diepenbeek , Belgium
| | - Jaco Vangronsveld
- d Centre for Environmental Sciences, Hasselt University , Diepenbeek , Belgium
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Transcriptome Response to Heavy Metals in Sinorhizobium meliloti CCNWSX0020 Reveals New Metal Resistance Determinants That Also Promote Bioremediation by Medicago lupulina in Metal-Contaminated Soil. Appl Environ Microbiol 2017; 83:AEM.01244-17. [PMID: 28778889 DOI: 10.1128/aem.01244-17] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Accepted: 07/26/2017] [Indexed: 01/16/2023] Open
Abstract
The symbiosis of the highly metal-resistant Sinorhizobium meliloti CCNWSX0020 and Medicago lupulina has been considered an efficient tool for bioremediation of heavy metal-polluted soils. However, the metal resistance mechanisms of S. meliloti CCNWSX00200 have not been elucidated in detail. Here we employed a comparative transcriptome approach to analyze the defense mechanisms of S. meliloti CCNWSX00200 against Cu or Zn exposure. Six highly upregulated transcripts involved in Cu and Zn resistance were identified through deletion mutagenesis, including genes encoding a multicopper oxidase (CueO), an outer membrane protein (Omp), sulfite oxidoreductases (YedYZ), and three hypothetical proteins (a CusA-like protein, a FixH-like protein, and an unknown protein), and the corresponding mutant strains showed various degrees of sensitivity to multiple metals. The Cu-sensitive mutant (ΔcueO) and three mutants that were both Cu and Zn sensitive (ΔyedYZ, ΔcusA-like, and ΔfixH-like) were selected for further study of the effects of these metal resistance determinants on bioremediation. The results showed that inoculation with the ΔcueO mutant severely inhibited infection establishment and nodulation of M. lupulina under Cu stress, while inoculation with the ΔyedYZ and ΔfixH-like mutants decreased just the early infection frequency and nodulation under Cu and Zn stresses. In contrast, inoculation with the ΔcusA-like mutant almost led to loss of the symbiotic capacity of M. lupulina to even grow in uncontaminated soil. Moreover, the antioxidant enzyme activity and metal accumulation in roots of M. lupulina inoculated with all mutants were lower than those with the wild-type strain. These results suggest that heavy metal resistance determinants may promote bioremediation by directly or indirectly influencing formation of the rhizobium-legume symbiosis.IMPORTANCE Rhizobium-legume symbiosis has been promoted as an appropriate tool for bioremediation of heavy metal-contaminated soils. Considering the plant-growth-promoting traits and survival advantage of metal-resistant rhizobia in contaminated environments, more heavy metal-resistant rhizobia and genetically manipulated strains were investigated. In view of the genetic diversity of metal resistance determinants in rhizobia, their effects on phytoremediation by the rhizobium-legume symbiosis must be different and depend on their specific assigned functions. Our work provides a better understanding of the mechanism of heavy metal resistance determinants involved in the rhizobium-legume symbiosis, and in further studies, genetically modified rhizobia harboring effective heavy metal resistance determinants may be engineered for the practical application of rhizobium-legume symbiosis for bioremediation in metal-contaminated soils.
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Mishra J, Singh R, Arora NK. Alleviation of Heavy Metal Stress in Plants and Remediation of Soil by Rhizosphere Microorganisms. Front Microbiol 2017; 8:1706. [PMID: 28932218 PMCID: PMC5592232 DOI: 10.3389/fmicb.2017.01706] [Citation(s) in RCA: 202] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 08/23/2017] [Indexed: 11/23/2022] Open
Abstract
Increasing concentration of heavy metals (HM) due to various anthropogenic activities is a serious problem. Plants are very much affected by HM pollution particularly in contaminated soils. Survival of plants becomes tough and its overall health under HM stress is impaired. Remediation of HM in contaminated soil is done by physical and chemical processes which are costly, time-consuming, and non-sustainable. Metal–microbe interaction is an emerging but under-utilized technology that can be exploited to reduce HM stress in plants. Several rhizosphere microorganisms are known to play essential role in the management of HM stresses in plants. They can accumulate, transform, or detoxify HM. In general, the benefit from these microbes can have a vast impact on plant’s health. Plant–microbe associations targeting HM stress may provide another dimension to existing phytoremediation and rhizoremediation uses. In this review, applied aspects and mechanisms of action of heavy metal tolerant-plant growth promoting (HMT-PGP) microbes in ensuring plant survival and growth in contaminated soils are discussed. The use of HMT-PGP microbes and their interaction with plants in remediation of contaminated soil can be the approach for the future. This low input and sustainable biotechnology can be of immense use/importance in reclaiming the HM contaminated soils, thus increasing the quality and yield of such soils.
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Affiliation(s)
- Jitendra Mishra
- Rhizosphere Microbiology Laboratory, Department of Environmental Microbiology, Babasaheb Bhimrao Ambedkar UniversityLucknow, India
| | - Rachna Singh
- Rhizosphere Microbiology Laboratory, Department of Environmental Microbiology, Babasaheb Bhimrao Ambedkar UniversityLucknow, India
| | - Naveen K Arora
- Rhizosphere Microbiology Laboratory, Department of Environmental Microbiology, Babasaheb Bhimrao Ambedkar UniversityLucknow, India
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Ye S, Zeng G, Wu H, Zhang C, Dai J, Liang J, Yu J, Ren X, Yi H, Cheng M, Zhang C. Biological technologies for the remediation of co-contaminated soil. Crit Rev Biotechnol 2017; 37:1062-1076. [DOI: 10.1080/07388551.2017.1304357] [Citation(s) in RCA: 311] [Impact Index Per Article: 44.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Shujing Ye
- College of Environmental Science and Engineering, Hunan University, Changsha, PR China
- Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, PR China
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha, PR China
- Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, PR China
| | - Haipeng Wu
- College of Environmental Science and Engineering, Hunan University, Changsha, PR China
- Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, PR China
- Changjiang River Scientific Research Institute, Wuhan, PR China
| | - Chang Zhang
- College of Environmental Science and Engineering, Hunan University, Changsha, PR China
- Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, PR China
| | - Juan Dai
- College of Environmental Science and Engineering, Hunan University, Changsha, PR China
- Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, PR China
- Changjiang River Scientific Research Institute, Wuhan, PR China
| | - Jie Liang
- College of Environmental Science and Engineering, Hunan University, Changsha, PR China
- Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, PR China
| | - Jiangfang Yu
- College of Environmental Science and Engineering, Hunan University, Changsha, PR China
- Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, PR China
| | - Xiaoya Ren
- College of Environmental Science and Engineering, Hunan University, Changsha, PR China
- Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, PR China
| | - Huan Yi
- College of Environmental Science and Engineering, Hunan University, Changsha, PR China
- Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, PR China
| | - Min Cheng
- College of Environmental Science and Engineering, Hunan University, Changsha, PR China
- Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, PR China
| | - Chen Zhang
- College of Environmental Science and Engineering, Hunan University, Changsha, PR China
- Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha, PR China
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Wen Z, Shi L, Tang Y, Shen Z, Xia Y, Chen Y. Effects of Pisolithus tinctorius and Cenococcum geophilum inoculation on pine in copper-contaminated soil to enhance phytoremediation. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2017; 19:387-394. [PMID: 27739883 DOI: 10.1080/15226514.2016.1244155] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We used Pisolithus tinctorius and Cenococcum geophilum to determine the copper (Cu) resistance of ectomycorrhizal (ECM) fungi and their potential for improving phytoremediation of Cu-contaminated soil by Chinese red pine (Pinus tabulaeformis). The results showed that nutrient accumulation in C. geophilum mycelium was significantly lower under higher Cu concentrations in the soil, which was not observed in P. tinctorius. Meanwhile, P. tinctorius exhibited greater Cu tolerance than C. geophilum. Inoculation with ECM fungi significantly improved the growth of pine shoots planted in polluted soil in pot experiments (p < 0.01). The total accumulated Cu in pine seedlings planted in Cu-contaminated soil increased by 72.8% and 113.3% when inoculated with P. tinctorius and C. geophilum, respectively, indicating that ECM fungi may help their host to phytoextract heavy metals. Furthermore, the majority of the total absorbed metals remained in the roots, confirming the ability of ECM fungi to promote heavy metal phytostabilization. There were no differences between the effects of the two fungi in helping the host stabilize and absorb Cu, even though they have different Cu tolerances. Inoculation with ECM fungi can benefit plant establishment in polluted environments and assist plants with phytoremediating heavy-metal-contaminated soils.
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Affiliation(s)
- Zhugui Wen
- a College of Life Sciences , Nanjing Agricultural University , Nanjing , China
- b Jiangsu Coastal Area Institute of Agricultural Sciences , Yancheng , China
| | - Liang Shi
- a College of Life Sciences , Nanjing Agricultural University , Nanjing , China
| | - Yangze Tang
- a College of Life Sciences , Nanjing Agricultural University , Nanjing , China
| | - Zhenguo Shen
- a College of Life Sciences , Nanjing Agricultural University , Nanjing , China
- c Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource , National Joint Local Engineering Research Center for Rural Land Resources Use and Consolidation , Nanjing , China
| | - Yan Xia
- a College of Life Sciences , Nanjing Agricultural University , Nanjing , China
| | - Yahua Chen
- a College of Life Sciences , Nanjing Agricultural University , Nanjing , China
- c Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource , National Joint Local Engineering Research Center for Rural Land Resources Use and Consolidation , Nanjing , China
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Khalid SAL. Isolation and characterization of heavy metals resistant Rhizobium isolates from different governorates in Egypt. ACTA ACUST UNITED AC 2017. [DOI: 10.5897/ajb2017.15930] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Kaewtubtim P, Meeinkuirt W, Seepom S, Pichtel J. Radionuclide ( 226Ra, 232Th, 40K) accumulation among plant species in mangrove ecosystems of Pattani Bay, Thailand. MARINE POLLUTION BULLETIN 2017; 115:391-400. [PMID: 28012738 DOI: 10.1016/j.marpolbul.2016.12.050] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 12/07/2016] [Accepted: 12/16/2016] [Indexed: 06/06/2023]
Abstract
Little is known regarding phytoremediation of radionuclides from soil; even less is known about radionuclide contamination and removal in tropical ecosystems such as mangrove forests. In mangrove forests in Pattani Bay, Thailand, 18 plant species from 17 genera were evaluated for radionuclide concentrations within selected plant parts. Two shrub species, Avicennia marina and Pluchea indica, accumulated the highest 232Th (24.6Bqkg-1) and 40K (220.7Bqkg-1) activity concentrations in roots, respectively. Furthermore, the aquatic species Typha angustifolia accumulated highest 232Th, 40K and 226Ra activity concentrations (85.2, 363.5, 16.6Bqkg-1, respectively) with the highest transfer factors (TFs) (3.0, 2.0, 5.9, respectively) in leaves. Leaves of T. angustifolia had an absorbed dose rate in air (D) over the recommended value (74.8nGyh-1) that was considered sufficiently high to be of concern for human consumption.
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Affiliation(s)
- Pungtip Kaewtubtim
- Department of Science, Faculty of Science and Technology, Prince of Songkla University Pattani Campus, Pattani 94000, Thailand
| | | | - Sumalee Seepom
- Department of Science, Faculty of Science and Technology, Prince of Songkla University Pattani Campus, Pattani 94000, Thailand
| | - John Pichtel
- Ball State University, Natural Resources and Environmental Management, Muncie, IN 47306, USA
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Kong Z, Deng Z, Glick BR, Wei G, Chou M. A nodule endophytic plant growth-promoting Pseudomonas and its effects on growth, nodulation and metal uptake in Medicago lupulina under copper stress. ANN MICROBIOL 2016. [DOI: 10.1007/s13213-016-1235-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Saadani O, Fatnassi IC, Chiboub M, Abdelkrim S, Barhoumi F, Jebara M, Jebara SH. In situ phytostabilisation capacity of three legumes and their associated Plant Growth Promoting Bacteria (PGPBs) in mine tailings of northern Tunisia. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2016; 130:263-269. [PMID: 27151677 DOI: 10.1016/j.ecoenv.2016.04.032] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 04/23/2016] [Accepted: 04/25/2016] [Indexed: 06/05/2023]
Abstract
PGPBs-legumes associations represent an alternative procedure for phytostabilisation of heavy metals polluted soils mainly generated by industrial and agricultural practices. In this study we evaluated the capacity of Vicia faba, Lens culinaris and Sulla coronaria, inoculated in situ by specific heavy metals resistant inocula, for the phytostabilisation of copper, lead and cadmium respectively. The experimentation was performed in mine tailings of northern Tunisia. Results proved that inoculation enhanced roots and shoots biomass production of faba bean by 14% and 12%, respectively, and significantly improved pods yield by 91%. In lentil, the inoculation ameliorated shoot biomass up to 27%. The highest nitrogen fixation was recorded by Sulla coronaria. The three symbioses accumulated heavy metals essentially in roots, and poorly in shoots. In addition, cadmium accumulation in roots of inoculated sulla was enhanced by 39%. Furthermore, inoculations decreased heavy metals availability in the soil up to -10% of Cu and -47% of Pb respectively in roots of faba bean and lentil. Our results suggested a positive effect of co-inoculation of legumes by appropriate heavy metals resistant PGPBs for the phytostabilisation of mine tailings. Elsewhere, the enhancement in the antioxidant enzymes activities demonstrated the role of the three inocula to alleviate the heavy metals induced stress.
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Affiliation(s)
- Omar Saadani
- Centre de Biotechnologie Borj Cedria, University Tunis El Manar, BP 901, 2050 Hammam Lif, Tunisia.
| | - Imen Challougui Fatnassi
- Centre de Biotechnologie Borj Cedria, University Tunis El Manar, BP 901, 2050 Hammam Lif, Tunisia
| | - Manel Chiboub
- Centre de Biotechnologie Borj Cedria, University Tunis El Manar, BP 901, 2050 Hammam Lif, Tunisia
| | - Souhir Abdelkrim
- Centre de Biotechnologie Borj Cedria, University Tunis El Manar, BP 901, 2050 Hammam Lif, Tunisia
| | - Fathi Barhoumi
- Centre de Biotechnologie Borj Cedria, University Tunis El Manar, BP 901, 2050 Hammam Lif, Tunisia
| | - Moez Jebara
- Centre de Biotechnologie Borj Cedria, University Tunis El Manar, BP 901, 2050 Hammam Lif, Tunisia
| | - Salwa Harzalli Jebara
- Centre de Biotechnologie Borj Cedria, University Tunis El Manar, BP 901, 2050 Hammam Lif, Tunisia
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Tripathi V, Edrisi SA, O'Donovan A, Gupta VK, Abhilash PC. Bioremediation for Fueling the Biobased Economy. Trends Biotechnol 2016; 34:775-777. [PMID: 27424153 DOI: 10.1016/j.tibtech.2016.06.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Revised: 06/21/2016] [Accepted: 06/24/2016] [Indexed: 12/22/2022]
Abstract
Increasing CO2 emission, land degradation, and pollution are major environmental challenges that need urgent global attention. Remediation strategies are essential for tackling these issues concurrently. Here we propose integrating bioremediation with CO2 sequestration for revitalizing polluted land while deriving bioproducts from renewable and waste biomass for fueling a sustainable bioeconomy.
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Affiliation(s)
- Vishal Tripathi
- Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi 221005, India
| | - Sheikh A Edrisi
- Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi 221005, India
| | - Anthonia O'Donovan
- Molecular Glyco-biotechnology Group, Discipline of Biochemistry, School of Natural Sciences, National University of Ireland Galway, Galway H91CF50, Ireland
| | - Vijai K Gupta
- Molecular Glyco-biotechnology Group, Discipline of Biochemistry, School of Natural Sciences, National University of Ireland Galway, Galway H91CF50, Ireland.
| | - P C Abhilash
- Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi 221005, India.
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El Aafi N, Saidi N, Maltouf AF, Perez-Palacios P, Dary M, Brhada F, Pajuelo E. Prospecting metal-tolerant rhizobia for phytoremediation of mining soils from Morocco using Anthyllis vulneraria L. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:4500-4512. [PMID: 25315928 DOI: 10.1007/s11356-014-3596-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Accepted: 09/11/2014] [Indexed: 06/04/2023]
Abstract
The aim of this work was using the legume plant Anthyllis vulneraria L. (ecotype metallicolous) as a trap plant, in order to isolate metal-tolerant rhizobial strains from metal-contaminated soils from Morocco, with pollution indexes spanning three orders of magnitude. As bioindicator, soil bacterial density was inversely correlated to the pollution index. Forty-three bulk soil bacteria and sixty two bacteria from nodules were isolated. The resistance of bacteria from nodules to heavy metals was four to ten times higher than that of bulk soil bacteria, reaching high maximum tolerable concentrations for Cd (2 mM), Cu (2 mM), Pb (7 mM), and Zn (3 mM). Besides, some strains show multiple metal-tolerant abilities and great metal biosorption onto the bacterial surface. Amplification and restriction analysis of ribosomal 16S rDNA (ARDRA) and 16S ribosomal DNA (rDNA) sequencing were used to assess biodiversity and phylogenetic position among bacteria present in nodules. Our results suggest that a great diversity of non-rhizobial bacteria (alpha- and gamma-proteobacteria) colonize nodules of Anthyllis plants in contaminated soils. Taking together, our results evidence that, in polluted soils, rhizobia can be displaced by non-rhizobial (and hence, non-fixing) strains from nodules. Thus, the selection of metal-resistant rhizobia is a key step for using A. vulneraria symbioses for in situ phytoremediation.
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Affiliation(s)
- N El Aafi
- Laboratory of Microbiology and Molecular Biology, Faculty of Sciences, University Mohamed V at Agdal, Rabat, Morocco,
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Hao X, Xie P, Zhu YG, Taghavi S, Wei G, Rensing C. Copper tolerance mechanisms of Mesorhizobium amorphae and its role in aiding phytostabilization by Robinia pseudoacacia in copper contaminated soil. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:2328-2340. [PMID: 25594414 DOI: 10.1021/es504956a] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The legume-rhizobium symbiosis has been proposed as an important system for phytoremediation of heavy metal contaminated soils due to its beneficial activity of symbiotic nitrogen fixation. However, little is known about metal resistant mechanism of rhizobia and the role of metal resistance determinants in phytoremediation. In this study, copper resistance mechanisms were investigated for a multiple metal resistant plant growth promoting rhizobium, Mesorhizobium amorphae 186. Three categories of determinants involved in copper resistance were identified through transposon mutagenesis, including genes encoding a P-type ATPase (CopA), hypothetical proteins, and other proteins (a GTP-binding protein and a ribosomal protein). Among these determinants, copA played the dominant role in copper homeostasis of M. amorphae 186. Mutagenesis of a hypothetical gene lipA in mutant MlipA exhibited pleiotropic phenotypes including sensitivity to copper, blocked symbiotic capacity and inhibited growth. In addition, the expression of cusB encoding part of an RND-type efflux system was induced by copper. To explore the possible role of copper resistance mechanism in phytoremediation of copper contaminated soil, the symbiotic nodulation and nitrogen fixation abilities were compared using a wild-type strain, a copA-defective mutant, and a lipA-defective mutant. Results showed that a copA deletion did not affect the symbiotic capacity of rhizobia under uncontaminated condition, but the protective role of copA in symbiotic processes at high copper concentration is likely concentration-dependent. In contrast, inoculation of a lipA-defective strain led to significant decreases in the functional nodule numbers, total N content, plant biomass and leghemoglobin expression level of Robinia pseudoacacia even under conditions of uncontaminated soil. Moreover, plants inoculated with lipA-defective strain accumulated much less copper than both the wild-type strain and the copA-defective strain, suggesting an important role of a healthy symbiotic relationship between legume and rhizobia in phytostabilization.
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Affiliation(s)
- Xiuli Hao
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, College of Life Sciences, Northwest A&F University , Yangling, Shaanxi 712100, China
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Xie P, Hao X, Herzberg M, Luo Y, Nies DH, Wei G. Genomic analyses of metal resistance genes in three plant growth promoting bacteria of legume plants in Northwest mine tailings, China. J Environ Sci (China) 2015; 27:179-187. [PMID: 25597676 DOI: 10.1016/j.jes.2014.07.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 06/11/2014] [Accepted: 07/31/2014] [Indexed: 06/04/2023]
Abstract
To better understand the diversity of metal resistance genetic determinant from microbes that survived at metal tailings in northwest of China, a highly elevated level of heavy metal containing region, genomic analyses was conducted using genome sequence of three native metal-resistant plant growth promoting bacteria (PGPB). It shows that: Mesorhizobium amorphae CCNWGS0123 contains metal transporters from P-type ATPase, CDF (Cation Diffusion Facilitator), HupE/UreJ and CHR (chromate ion transporter) family involved in copper, zinc, nickel as well as chromate resistance and homeostasis. Meanwhile, the putative CopA/CueO system is expected to mediate copper resistance in Sinorhizobium meliloti CCNWSX0020 while ZntA transporter, assisted with putative CzcD, determines zinc tolerance in Agrobacterium tumefaciens CCNWGS0286. The greenhouse experiment provides the consistent evidence of the plant growth promoting effects of these microbes on their hosts by nitrogen fixation and/or indoleacetic acid (IAA) secretion, indicating a potential in-site phytoremediation usage in the mining tailing regions of China.
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Affiliation(s)
- Pin Xie
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, College of Life Science, Northwest A&F University, Yangling, Shaanxi 712100, China; Molecular Microbiology, Institute for Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), 06120, Germany.
| | - Xiuli Hao
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, College of Life Science, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Martin Herzberg
- Molecular Microbiology, Institute for Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), 06120, Germany
| | - Yantao Luo
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, College of Life Science, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Dietrich H Nies
- Molecular Microbiology, Institute for Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), 06120, Germany
| | - Gehong Wei
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, College of Life Science, Northwest A&F University, Yangling, Shaanxi 712100, China.
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Ghnaya T, Mnassri M, Ghabriche R, Wali M, Poschenrieder C, Lutts S, Abdelly C. Nodulation by Sinorhizobium meliloti originated from a mining soil alleviates Cd toxicity and increases Cd-phytoextraction in Medicago sativa L. FRONTIERS IN PLANT SCIENCE 2015; 6:863. [PMID: 26528320 PMCID: PMC4604267 DOI: 10.3389/fpls.2015.00863] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2015] [Accepted: 09/29/2015] [Indexed: 05/13/2023]
Abstract
Besides their role in nitrogen supply to the host plants as a result of symbiotic N fixation, the association between legumes and Rhizobium could be useful for the rehabilitation of metal-contaminated soils by phytoextraction. A major limitation presents the metal-sensitivity of the bacterial strains. The aim of this work was to explore the usefulness of Sinorhizobium meliloti originated from a mining site for Cd phytoextraction by Medicago sativa. Inoculated and non-inoculated plants were cultivated for 60 d on soils containing 50 and/or 100 mg Cd kg(-1) soil. The inoculation hindered the occurrence of Cd- induced toxicity symptoms that appeared in the shoots of non-inoculated plants. This positive effect of S. meliloti colonization was accompanied by an increase in biomass production and improved nutrient acquisition comparatively to non-inoculated plants. Nodulation enhanced Cd absorption by the roots and Cd translocation to the shoots. The increase of plant biomass concomitantly with the increase of Cd shoot concentration in inoculated plants led to higher potential of Cd-phytoextraction in these plants. In the presence of 50 mg Cd kg(-1) in the soil, the amounts of Cd extracted in the shoots were 58 and 178 μg plant(-1) in non-inoculated and inoculated plants, respectively. This study demonstrates that this association M. sativa-S. meliloti may be an efficient biological system to extract Cd from contaminated soils.
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Affiliation(s)
- Tahar Ghnaya
- Laboratoire des Plantes Extremophiles, Centre de Biotechnologies de la Technopole de Borj CedriaHammam Lif, Tunisia
- *Correspondence: Tahar Ghnaya
| | - Majda Mnassri
- Laboratoire des Plantes Extremophiles, Centre de Biotechnologies de la Technopole de Borj CedriaHammam Lif, Tunisia
| | - Rim Ghabriche
- Laboratoire des Plantes Extremophiles, Centre de Biotechnologies de la Technopole de Borj CedriaHammam Lif, Tunisia
| | - Mariem Wali
- Laboratoire des Plantes Extremophiles, Centre de Biotechnologies de la Technopole de Borj CedriaHammam Lif, Tunisia
| | - Charlotte Poschenrieder
- Departamento de Fisiologia Vegetal, Facultad de Ciencias, Universidad Autonoma de BarcelonaBarcelona, Spain
| | - Stanley Lutts
- Groupe de Recherche en Physiologie Végétale, Earth and Life Institute – Agronomy, Université Catholique de LouvainLouvain-la-Neuve, Belgium
| | - Chedly Abdelly
- Laboratoire des Plantes Extremophiles, Centre de Biotechnologies de la Technopole de Borj CedriaHammam Lif, Tunisia
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Teng Y, Wang X, Li L, Li Z, Luo Y. Rhizobia and their bio-partners as novel drivers for functional remediation in contaminated soils. FRONTIERS IN PLANT SCIENCE 2015; 6:32. [PMID: 25699064 PMCID: PMC4318275 DOI: 10.3389/fpls.2015.00032] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 01/13/2015] [Indexed: 05/20/2023]
Abstract
Environmental pollutants have received considerable attention due to their serious effects on human health. There are physical, chemical, and biological means to remediate pollution; among them, bioremediation has become increasingly popular. The nitrogen-fixing rhizobia are widely distributed in the soil and root ecosystems and can increase legume growth and production by supplying nitrogen, resulting in the reduced need for fertilizer applications. Rhizobia also possess the biochemical and ecological capacity to degrade organic pollutants and are resistant to heavy metals, making them useful for rehabilitating contaminated soils. Moreover, rhizobia stimulate the survival and action of other biodegrading bacteria, thereby lowering the concentration of pollutants. The synergistic action of multiple rhizobial strains enhances both plant growth and the availability of pollutants ranging from heavy metals to persistent organic pollutants. Because phytoremediation has some restrictions, the beneficial interaction between plants and rhizobia provides a promising option for remediation. This review describes recent advances in the exploitation of rhizobia for the rehabilitation of contaminated soil and the biochemical and molecular mechanisms involved, thereby promoting further development of this novel bioremediation strategy into a widely accepted technique.
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Affiliation(s)
- Ying Teng
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of SciencesNanjing, China
- *Correspondence: Ying Teng, Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road No. 71, Nanjing, Jiangsu 210008, China e-mail:
| | - Xiaomi Wang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of SciencesNanjing, China
| | - Lina Li
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of SciencesNanjing, China
| | - Zhengao Li
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of SciencesNanjing, China
| | - Yongming Luo
- Key Laboratory of Coastal Zone Environmental Processes, Yantai Institute of Coastal Zone Research, Chinese Academy of SciencesYantai, China
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Abd-Alla MH, Bagy MK, El-enany AWES, Bashandy SR. Activation of Rhizobium tibeticum with flavonoids enhances nodulation, nitrogen fixation, and growth of fenugreek (Trigonella foenum-graecum L.) grown in cobalt-polluted soil. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2014; 66:303-315. [PMID: 24366585 DOI: 10.1007/s00244-013-9980-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2013] [Accepted: 12/03/2013] [Indexed: 06/03/2023]
Abstract
The goal of this study was to investigate the response of activation of Rhizobium tibeticum with mixture of hesperetin and apigenin to improve growth, nodulation, and nitrogen fixation of fenugreek grown under cobalt (Co) stress. The current study showed that high concentrations of Co-induced noxious effects on rhizobial growth, nod gene expression, nodulation, phenylalanine ammonia-lyase (PAL) and glutamine synthetase (GS) activities, total flavonoid content, and nitrogen fixation. Addition of a mixture of hesperetin and apigenin to growth medium supplemented with different concentrations of Co significantly increased bacterial growth. PAL activity of roots grown hydroponically at 100 mg kg(-1) Co and inoculated with induced R. tibeticum was significantly increased compared with plants receiving uninduced R. tibeticum. Total flavonoid content of root exudates of plants inoculated with activated R. tibeticum was significantly increased compared with inoculated plants with unactivated R. tibeticum or uninoculated plants at variant Co dosages. Application of 50 mg kg(-1) Co significantly increased nodulation, GS, nitrogenase activity, and biomass of plants inoculated with either or uninduced R. tibeticum. The total number and fresh mass of nodules, nitrogenase activity, and biomass of plants inoculated with induced cells grown in soil treated with 100 and 200 mg kg(-1) Co were significantly increased compared with plants inoculated with uninduced cells. Induced R. tibeticum with flavonoids significantly alleviates the adverse effect of Co on nod gene expression and therefore enhances nitrogen fixation. Induction of R. tibeticum with compatible flavonoids could be of practical importance in augmenting growth and nitrogen fixation of fenugreek grown in a Co-contaminated agroecosystem.
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Affiliation(s)
- Mohamed Hemida Abd-Alla
- Botany and Microbiology Department, Faculty of Science, Assiut University, Assuit, 71516, Egypt
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