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Guo L, Li Z, Xu J. Effects of Cadmium Stress on Bacterial and Fungal Communities in the Whitefly Bemisia tabaci. Int J Mol Sci 2023; 24:13588. [PMID: 37686394 PMCID: PMC10488276 DOI: 10.3390/ijms241713588] [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: 07/19/2023] [Revised: 08/23/2023] [Accepted: 08/31/2023] [Indexed: 09/10/2023] Open
Abstract
Heavy metal contamination is among the most prominent environmental problems in China, posing serious threats to both ecosystem and human health. Among the diverse heavy metal contaminants, cadmium is the most serious. The whitefly Bemisia tabaci is a cosmopolitan pest capable of causing severe damage to a broad range of agricultural crops, especially vegetables. At present, little is known about the effects of cadmium stress on B. tabaci, including on its bacterial and fungal communities. In the current study, we investigated the effects of cadmium on bacterial and fungal communities in whiteflies. Meta-barcode sequencing of the 16S rRNA gene revealed that the whitefly bacterial community contained 264 operational taxonomic units (OTUs) belonging to 201 known genera and 245 known species. The top five most frequent bacterial genera were Rickettsia, Rhodococcus, Candidatus Portiera, Candidatus Hamiltonella, and Achromobacter. Meta-barcode sequencing of the fungal ITS locus revealed that the whitefly fungal community contained 357 OTUs belonging to 187 known genera and 248 known species. The top five most frequent fungal genera were Wallemia, unclassified_f_Dipodascaceae, Apiotrichum, Penicillium, and unclassified_o_Saccharomycetales. Cadmium exposure reduced the fungal OTU richness but increased the bacterial Shannon and Simpson diversity indices in whiteflies. In addition, upon exposure to cadmium, the microbial community composition in whiteflies changed significantly, with increased prevalence of the bacterial genera Rhodococcus and Exiguobacterium and fungal genus Wallemia. Our results indicate that the whitefly microbiota likely contributed to their adaptation and resistance to cadmium and suggested that whiteflies may contain microbes that could help remediate cadmium contamination in natural environments and agricultural fields.
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Affiliation(s)
- Litao Guo
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China; (L.G.); (Z.L.)
| | - Zhimin Li
- Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China; (L.G.); (Z.L.)
| | - Jianping Xu
- Department of Biology, McMaster University, Hamilton, ON L8S 4K1, Canada
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Chi Y, You Y, Wang J, Chen X, Chu S, Wang R, Zhang X, Yin S, Zhang D, Zhou P. Two plant growth-promoting bacterial Bacillus strains possess different mechanisms in affecting cadmium uptake and detoxification of Solanum nigrum L. CHEMOSPHERE 2022; 305:135488. [PMID: 35764116 DOI: 10.1016/j.chemosphere.2022.135488] [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: 04/27/2022] [Revised: 06/20/2022] [Accepted: 06/22/2022] [Indexed: 05/22/2023]
Abstract
Microorganisms affect cadmium (Cd) extraction by hyperaccumulators to varying degrees, but the potential mechanism has not been completely studied. Here, two plant growth-promoting bacteria (PGPB, Bacillus paranthracis NT1 and Bacillus megaterium NCT-2) were assessed for their influence on Cd uptake by Solanum nigrum L. and their influence mechanisms. The results showed that both two strains could regulate phytohormones secretion, alleviate oxidative stress and promote S. nigrum growth when exposed to Cd (dry weight was significantly increased by 21.51% (strain NCT-2) and 21.23% (strain NT1) compared with the control, respectively). Additionally, strain NCT-2 significantly elevated the translocation factor (TF) and bioconcentration factor (BCF), and thus significantly facilitated total Cd uptake by 41.80% of S. nigrum, whereas strain NT1 significantly reduced the BCF and TF, resulting in insignificant effect on total Cd uptake of S. nigrum compared with the control. Results of qPCR illustrated that the two strains influenced the detoxification of Cd in S. nigrum by affecting the expression of antioxidant enzyme genes and gene PDR2. Moreover, the differential expression of heavy metal transport genes IRT1 and HMA may lead to the difference of Cd accumulation in S. nigrum. Principal component analysis and Pearson correlation coefficient analysis further verified the positive roles of salicylic acid and indole-3-acetic acid on Cd detoxification of S. nigrum, and the positive correlation relationship between transportation of Cd from underground to shoot, plant biomass and Cd uptake. Altogether, our results demonstrated that these two PGPB have great potential in helping plants detoxify Cd and could provide insights into the mechanism of PGPB-assisted phytoremediation of Cd-contaminated soil.
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Affiliation(s)
- Yaowei Chi
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Areas, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Yimin You
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Areas, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Juncai Wang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Areas, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xunfeng Chen
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Areas, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Shaohua Chu
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Areas, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Renyuan Wang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Areas, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xia Zhang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Areas, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Shan Yin
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China; Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, 800 Dongchuan Rd, Shanghai, 200240, China; Shanghai Urban Forest Ecosystem Research Station, National Forestry and Grassland Administration, 800 Dongchuan Rd., Shanghai, 200240, China
| | - Dan Zhang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Areas, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Pei Zhou
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Areas, Shanghai Jiao Tong University, Shanghai, 200240, China; Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, 800 Dongchuan Rd, Shanghai, 200240, China.
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The Road to Practical Application of Cadmium Phytoremediation Using Rice. PLANTS 2021; 10:plants10091926. [PMID: 34579459 PMCID: PMC8469809 DOI: 10.3390/plants10091926] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/08/2021] [Accepted: 09/09/2021] [Indexed: 11/16/2022]
Abstract
Cadmium (Cd) is a toxic heavy metal that causes severe health issues in humans. Cd accumulates in the human body when foods produced in Cd-contaminated fields are eaten. Therefore, soil remediation of contaminated fields is necessary to provide safe foods. Rice is one of the primary candidates for phytoremediation. There is a genotypic variation of Cd concentration in the shoots and grains of rice. Using the world rice core collection, ‘Jarjan’, ‘Anjana Dhan’, and ‘Cho-ko-koku’ were observed with a significantly higher level of Cd accumulation in the shoots and grains. Moreover, OsHMA3, a heavy metal transporter, was identified as a responsive gene of quantitative trait locus (QTL) for high Cd concentration in the shoots of these three varieties likewise. However, it is difficult to apply practical phytoremediation to these varieties because of their unfavorable agricultural traits, such as shatter and easily lodged. New rice varieties and lines were bred for Cd phytoremediation using OsHMA3 as a DNA marker selection. All of them accumulated Cd in the shoots equal to or higher than ‘Cho-ko-koku’ with improved cultivation traits. Therefore, they can be used for practical Cd phytoremediation.
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Liu S, Liu H, Chen R, Ma Y, Yang B, Chen Z, Liang Y, Fang J, Xiao Y. Role of Two Plant Growth-Promoting Bacteria in Remediating Cadmium-Contaminated Soil Combined with Miscanthus floridulus (Lab.). PLANTS 2021; 10:plants10050912. [PMID: 34063227 PMCID: PMC8147505 DOI: 10.3390/plants10050912] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/27/2021] [Accepted: 04/28/2021] [Indexed: 11/19/2022]
Abstract
Miscanthus spp. are energy plants and excellent candidates for phytoremediation approaches of metal(loid)s-contaminated soils, especially when combined with plant growth-promoting bacteria. Forty-one bacterial strains were isolated from the rhizosphere soils and roots tissue of five dominant plants (Artemisia argyi Levl., Gladiolus gandavensis Vaniot Houtt, Boehmeria nivea L., Veronica didyma Tenore, and Miscanthus floridulus Lab.) colonizing a cadmium (Cd)-contaminated mining area (Huayuan, Hunan, China). We subsequently tested their plant growth-promoting (PGP) traits (e.g., production of indole-3-acetic acid, siderophore, and 1-aminocyclopropane-1-carboxylate deaminase) and Cd tolerance. Among bacteria, two strains, Klebsiella michiganensis TS8 and Lelliottia jeotgali MR2, presented higher Cd tolerance and showed the best results regarding in vitro growth-promoting traits. In the subsequent pot experiments using soil spiked with 10 mg Cd·kg−1, we investigated the effects of TS8 and MR2 strains on soil Cd phytoremediation when combined with M. floridulus (Lab.). After sixty days of planting M. floridulus (Lab.), we found that TS8 increased plant height by 39.9%, dry weight of leaves by 99.1%, and the total Cd in the rhizosphere soil was reduced by 49.2%. Although MR2 had no significant effects on the efficiency of phytoremediation, it significantly enhanced the Cd translocation from the root to the aboveground tissues (translocation factor > 1). The combination of K. michiganensis TS8 and M. floridulus (Lab.) may be an effective method to remediate Cd-contaminated soils, while the inoculation of L. jeotgali MR2 may be used to enhance the phytoextraction potential of M. floridulus.
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Affiliation(s)
- Shuming Liu
- College of Bioscience and Biotechnology, College of Resource and Environment, Hunan Agricultural University, Changsha 410128, China; (S.L.); (H.L.); (R.C.); (Y.M.); (B.Y.); (Z.C.); (Y.L.)
- Hunan Engineering Laboratory for Pollution Control and Waste Utilization in Swine Production, Changsha 410128, China
- Key Laboratory for Rural Ecosystem Health in Dongting Lake Area of Hunan Province, Changsha 410128, China
| | - Hongmei Liu
- College of Bioscience and Biotechnology, College of Resource and Environment, Hunan Agricultural University, Changsha 410128, China; (S.L.); (H.L.); (R.C.); (Y.M.); (B.Y.); (Z.C.); (Y.L.)
- Hunan Engineering Laboratory for Pollution Control and Waste Utilization in Swine Production, Changsha 410128, China
- Key Laboratory for Rural Ecosystem Health in Dongting Lake Area of Hunan Province, Changsha 410128, China
| | - Rui Chen
- College of Bioscience and Biotechnology, College of Resource and Environment, Hunan Agricultural University, Changsha 410128, China; (S.L.); (H.L.); (R.C.); (Y.M.); (B.Y.); (Z.C.); (Y.L.)
- Hunan Engineering Laboratory for Pollution Control and Waste Utilization in Swine Production, Changsha 410128, China
- Key Laboratory for Rural Ecosystem Health in Dongting Lake Area of Hunan Province, Changsha 410128, China
| | - Yong Ma
- College of Bioscience and Biotechnology, College of Resource and Environment, Hunan Agricultural University, Changsha 410128, China; (S.L.); (H.L.); (R.C.); (Y.M.); (B.Y.); (Z.C.); (Y.L.)
- Hunan Engineering Laboratory for Pollution Control and Waste Utilization in Swine Production, Changsha 410128, China
- Key Laboratory for Rural Ecosystem Health in Dongting Lake Area of Hunan Province, Changsha 410128, China
| | - Bo Yang
- College of Bioscience and Biotechnology, College of Resource and Environment, Hunan Agricultural University, Changsha 410128, China; (S.L.); (H.L.); (R.C.); (Y.M.); (B.Y.); (Z.C.); (Y.L.)
- Hunan Engineering Laboratory for Pollution Control and Waste Utilization in Swine Production, Changsha 410128, China
- Key Laboratory for Rural Ecosystem Health in Dongting Lake Area of Hunan Province, Changsha 410128, China
| | - Zhiyong Chen
- College of Bioscience and Biotechnology, College of Resource and Environment, Hunan Agricultural University, Changsha 410128, China; (S.L.); (H.L.); (R.C.); (Y.M.); (B.Y.); (Z.C.); (Y.L.)
| | - Yunshan Liang
- College of Bioscience and Biotechnology, College of Resource and Environment, Hunan Agricultural University, Changsha 410128, China; (S.L.); (H.L.); (R.C.); (Y.M.); (B.Y.); (Z.C.); (Y.L.)
| | - Jun Fang
- College of Bioscience and Biotechnology, College of Resource and Environment, Hunan Agricultural University, Changsha 410128, China; (S.L.); (H.L.); (R.C.); (Y.M.); (B.Y.); (Z.C.); (Y.L.)
- Hunan Engineering Laboratory for Pollution Control and Waste Utilization in Swine Production, Changsha 410128, China
- Key Laboratory for Rural Ecosystem Health in Dongting Lake Area of Hunan Province, Changsha 410128, China
- Correspondence: (J.F.); (Y.X.)
| | - Yunhua Xiao
- College of Bioscience and Biotechnology, College of Resource and Environment, Hunan Agricultural University, Changsha 410128, China; (S.L.); (H.L.); (R.C.); (Y.M.); (B.Y.); (Z.C.); (Y.L.)
- Hunan Engineering Laboratory for Pollution Control and Waste Utilization in Swine Production, Changsha 410128, China
- Key Laboratory for Rural Ecosystem Health in Dongting Lake Area of Hunan Province, Changsha 410128, China
- Correspondence: (J.F.); (Y.X.)
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Redha A, Al-Hasan R, Afzal M. Synergistic and concentration-dependent toxicity of multiple heavy metals compared with single heavy metals in Conocarpus lancifolius. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:23258-23272. [PMID: 33443733 PMCID: PMC8113142 DOI: 10.1007/s11356-020-12271-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 12/28/2020] [Indexed: 05/30/2023]
Abstract
While heavy metals (HMs) naturally occur in soil, anthropogenic activities can increase the level of these toxic elements. Conocarpus lancifolius Engl. (Combretaceae) was investigated as a potential phytoremediator of soils contaminated with HM containing crude oil. This study assessed the potential of C. lancifolius (CL), a locally available plant species in Kuwait, for resolving local issues of the HM-contaminated soils. The absorption, accumulation, and distribution of three toxic HMs (Cd, Ni, and Pb) and essential metals (Fe, Mg, and metalloid Se) were examined, and their role in plant toxicity and tolerance was evaluated. Conocarpus lancifolius plants were exposed to two different concentrations of single and mixed HMs for 30 days. The accumulation of HMs was determined in the roots, leaves, stems, and the soil using ICP/MS. Biomass, soil pH, proline and protein content, and bioaccumulation, extraction, and translocation factors were measured. The bioaccumulation, extraction, and transcription factors were all >1, indicating CC is a hyperaccumulator of HM. The HM accumulation in CL was concentration-dependent and depended on whether the plants were exposed to individual or mixed HMs. The C.C leaves, stems, and roots showed a significant accumulation of antioxidant constituents, such as proline, protein, Fe, Mg, and Se. There was an insignificant increase in the soil pH, and a decrease in plant biomass and a significant increase in protein, and osmoprotective-proline as a result of the interaction of mixed heavy metals that are more toxic than single heavy metals. This study indicates that C. lancifolius is a good candidate for phytoremediation of multiple HM-contaminated soils. Further studies to establish the phyto-physiological effect of multiple heavy metals are warranted.
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Affiliation(s)
- Amina Redha
- Department of Biological Studies, Faculty of Science, Kuwait University, Kuwait City, Kuwait
| | - Redha Al-Hasan
- Department of Biological Studies, Faculty of Science, Kuwait University, Kuwait City, Kuwait
| | - Mohammad Afzal
- Department of Biological Studies, Faculty of Science, Kuwait University, Kuwait City, Kuwait.
- , Gainesville, USA.
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Pathom-Aree W, Matako A, Rangseekaew P, Seesuriyachan P, Srinuanpan S. Performance of Actinobacteria isolated from rhizosphere soils on plant growth promotion under cadmium toxicity. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2021; 23:1497-1505. [PMID: 33913782 DOI: 10.1080/15226514.2021.1913992] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
This work aimed to evaluate the potential use of plant growth-promoting actinobacteria (PGPA) for enhanced cadmium (Cd) phytoremediation and plant growth. Forty-two actinobacteria were isolated from rhizosphere soils in Thailand. Among isolates tested, only Streptomyces phaeogriseichromatogenes isolate COS4, showed the high ability to produce siderophores as a plant growth stimulant and had a strong Cd tolerance potential. The significance of siderophores production and Cd tolerance ability under different Cd concentrations suggests the potential of isolate COS4 to work effectively. Plant culture revealed that the significant increase in root length, root to tip length, and total dried weight of sunflower were obtained after 2 h incubation of sunflower seeds with isolate COS4. The efficiency of Cd uptake was found to range between 42.3 and 61.3%. Translocation factor results confirmed that plant growth promoting S. phaeogriseichromatogenes isolate COS4-assisted phytoremediation can be considered as Cd absorbents for the restoration of polluted sites due to high translocation values.
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Affiliation(s)
- Wasu Pathom-Aree
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand
- Faculty of Science, Research Center of Microbial Diversity and Sustainable Utilization, Chiang Mai University, Chiang Mai, Thailand
| | - Alisa Matako
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand
| | - Pharada Rangseekaew
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand
| | - Phisit Seesuriyachan
- Division of Biotechnology, Faculty of Agro-Industry, Chiang Mai University, Chiang Mai, Thailand
| | - Sirasit Srinuanpan
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand
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Yaashikaa PR, Kumar PS, Saravanan A. Modeling and Cr(VI) ion uptake kinetics of Sorghum bicolor plant assisted by plant growth-promoting Pannonibacter phragmetitus: an ecofriendly approach. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:27307-27318. [PMID: 31278645 DOI: 10.1007/s11356-019-05764-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 06/17/2019] [Indexed: 06/09/2023]
Abstract
The research work focuses on the application of Cr(VI)-resistant plant growth-promoting bacteria Pannonibacter phragmetitus for enhancing Cr(VI) uptake by Sorghum bicolor. Significant increase in plant shoot and root characters was found when assisted by P. phragmetitus. The obtained strain showed 700 mg/L of chromium reduction at 24-h incubation. Indole-3 acetic acid (IAA) production by the bacterial strain was found to be 86.45 μg/mL. Pannonibacter phragmetitus solubilized tricalcium phosphate showing maximum solubilizing activity of PSI = 3.31. The qmax of P. phragmetitus was high in the wavelength of 600 nm. Langmuir isotherm best described the Cr(VI) ion uptake by the plant. The RL values reliably reduced with expanding Cr(VI) ion concentration from 25 to 150 mg/L. The outcomes of kinetic studies showed that compared with pseudo first-order, pseudo second-order kinetics better describes the plant Cr(VI) uptake rate. Elovich model describes the increased rates for attaining equilibrium. The equilibrium parameter values for different Cr(VI) ion concentrations range between 0 and 1 which describes the favorable condition for plant metal uptake at different concentrations. Graphical abstract.
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Affiliation(s)
| | - Ponnusamy Senthil Kumar
- Department of Chemical Engineering, SSN College of Engineering, Kalavakkam, Chennai, 603110, India.
| | - Anbalagan Saravanan
- Department of Biotechnology, Rajalakshmi Engineering College, Chennai, India
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Jan R, Khan MA, Asaf S, Lubna, Lee IJ, Kim KM. Metal Resistant Endophytic Bacteria Reduces Cadmium, Nickel Toxicity, and Enhances Expression of Metal Stress Related Genes with Improved Growth of Oryza Sativa, via Regulating Its Antioxidant Machinery and Endogenous Hormones. PLANTS (BASEL, SWITZERLAND) 2019; 8:E363. [PMID: 31547575 PMCID: PMC6844085 DOI: 10.3390/plants8100363] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 09/09/2019] [Accepted: 09/19/2019] [Indexed: 11/18/2022]
Abstract
The tolerance of plant growth-promoting endophytes (PGPEs) against various concentrations of cadmium (Cd) and nickel (Ni) was investigated. Two glutathione-producing bacterial strains (Enterobacter ludwigii SAK5 and Exiguobacterium indicum SA22) were screened for Cd and Ni accumulation and tolerance in contaminated media, which showed resistance up to 1.0 mM. Both strains were further evaluated by inoculating specific plants with the bacteria for five days prior to heavy metal treatment (0.5 and 1.0 mM). The enhancement of biomass and growth attributes such as the root length, shoot length, root fresh weight, shoot fresh weight, and chlorophyll content were compared between treated inoculated plants and treated non-inoculated plants. Both strains significantly increased the accumulation of Cd and Ni in inoculated plants. The accumulation of both heavy metals was higher in the roots than in the shoots, however; Ni accumulation was greater than Cd. Heavy metal stress-responsive genes such as OsGST, OsMTP1, and OsPCS1 were significantly upregulated in treated non-inoculated plants compared with treated inoculated plants, suggesting that both strains reduced heavy metal stress. Similarly, abscisic acid (ABA) was increased with increased heavy metal concentration; however, it was reduced in inoculated plants compared with non-inoculated plants. Salicylic acid (SA) was found to exert synergistic effects with ABA. The application of suitable endophytic bacteria can protect against heavy metal hyperaccumulation by enhancing detoxification mechanisms.
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Affiliation(s)
- Rahmatullah Jan
- School of Applied Biosciences, Kyungpook National University, Daegu 41566, Korea; (R.J.); (M.A.K.); (I.-J.L.)
| | - Muhammad Aaqil Khan
- School of Applied Biosciences, Kyungpook National University, Daegu 41566, Korea; (R.J.); (M.A.K.); (I.-J.L.)
| | - Sajjad Asaf
- Natural and Medical Science Research Center, University of Nizwa 616, Nizwa 611, Oman;
| | - Lubna
- Department of Botany, Garden Campus, Abdul Wali Khan University, Mardan 23200, Pakistan;
| | - In-Jung Lee
- School of Applied Biosciences, Kyungpook National University, Daegu 41566, Korea; (R.J.); (M.A.K.); (I.-J.L.)
| | - Kyung Min Kim
- School of Applied Biosciences, Kyungpook National University, Daegu 41566, Korea; (R.J.); (M.A.K.); (I.-J.L.)
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Chuaphasuk C, Prapagdee B. Effects of biochar-immobilized bacteria on phytoremediation of cadmium-polluted soil. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:23679-23688. [PMID: 31203543 DOI: 10.1007/s11356-019-05661-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 06/03/2019] [Indexed: 05/22/2023]
Abstract
This work is the first report of the ability of biochar-immobilized cadmium-resistant bacteria (CRB) on promoting the efficiency of cadmium phytoextraction by Chlorophytum laxum R.Br. The survival of CRB immobilized on biochar in cadmium-contaminated soil at a concentration of 75.45 mg kg-1 was studied. The results found that both CRB, namely Arthrobacter sp. TM6 and Micrococcus sp. MU1, can survive and grow in cadmium-contaminated soil. To study phytoextraction in the pot experiments, 2-month-old C. laxum was individually planted in cadmium-contaminated soil and divided into four treatments, including (i) untreated control, (ii) biochar, (iii) biochar-immobilized (BC) Arthrobacter sp., and (iv) BC-Micrococcus sp. The results found that biochar-immobilized CRB did not cause any effect to the root lengths and shoot heights of plants compared to the untreated control. Interestingly, inoculation of biochar-immobilized CRB significantly increased cadmium accumulation in the shoots and roots compared to the untreated control. In addition, the highest cadmium content in a whole plant, best phytoextraction performance, and greatest bioaccumulation factor was found in plant inoculated with BC-Micrococcus sp., followed by BC-Arthrobacter sp. In conclusion, inoculation of biochar-immobilized CRB enhanced cadmium accumulation and translocation of cadmium from the roots to shoots, suggesting further applying biochar-immobilized CRB in cadmium-polluted soil for promoting cadmium phytoextraction efficiency of ornamental plants. Graphical abstract.
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Affiliation(s)
- Chonticha Chuaphasuk
- Laboratory of Environmental Biotechnology, Faculty of Environment and Resource Studies, Mahidol University, Phutthamonthon, Nakhon Pathom, 73170, Thailand
| | - Benjaphorn Prapagdee
- Laboratory of Environmental Biotechnology, Faculty of Environment and Resource Studies, Mahidol University, Phutthamonthon, Nakhon Pathom, 73170, Thailand.
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