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Riseh RS, Vazvani MG, Hajabdollahi N, Thakur VK. Bioremediation of Heavy Metals by Rhizobacteria. Appl Biochem Biotechnol 2023; 195:4689-4711. [PMID: 36287331 PMCID: PMC10354140 DOI: 10.1007/s12010-022-04177-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/28/2022] [Indexed: 11/02/2022]
Abstract
Heavy elements accumulate rapidly in the soil due to industrial activities and the industrial revolution, which significantly impact the morphology, physiology, and yield of crops. Heavy metal contamination will eventually affect the plant tolerance threshold and cause changes in the plant genome and genetic structure. Changes in the plant genome lead to changes in encoded proteins and protein sequences. Consuming these mutated products can seriously affect human and animal health. Bioremediation is a process that can be applied to reduce the adverse effects of heavy metals in the soil. In this regard, bioremediation using plant growth-promoting rhizobacteria (PGPRs) as beneficial living agents can help to neutralize the negative interaction between the plant and the heavy metals. PGPRs suppress the adverse effects of heavy metals and the negative interaction of plant-heavy elements by different mechanisms such as biological adsorption and entrapment of heavy elements in extracellular capsules, reduction of metal ion concentration, and formation of complexes with metal ions inside the cell.
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Affiliation(s)
- Roohallah Saberi Riseh
- Department of Plant Protection, Faculty of Agriculture, Vali-E-Asr University of Rafsanjan, Imam Khomeini Square, Rafsanjan, 7718897111 Iran
| | - Mozhgan Gholizadeh Vazvani
- Department of Plant Protection, Faculty of Agriculture, Vali-E-Asr University of Rafsanjan, Imam Khomeini Square, Rafsanjan, 7718897111 Iran
| | - Najmeh Hajabdollahi
- Department of Plant Protection, Faculty of Agriculture, Vali-E-Asr University of Rafsanjan, Imam Khomeini Square, Rafsanjan, 7718897111 Iran
| | - Vijay Kumar Thakur
- Biorefining and Advanced Materials Research Center, Scotland’s Rural College (SRUC), Edinburgh, EH9 3JG UK
- School of Engineering, University of Petroleum & Energy Studies (UPES), Dehradun, 248007 India
- Centre for Research and Development, Chandigarh University, Mohali, 140413 Punjab India
- Department of Biotechnology, Graphic Era Deemed to Be University, Dehradun, 248002 Uttarakhand India
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Spiniello I, De Carluccio M, Castiglione S, Amineva E, Kostryukova N, Cicatelli A, Rizzo L, Guarino F. Landfill leachate treatment by a combination of a multiple plant hybrid constructed wetland system with a solar photoFenton process in a raceway pond reactor. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 331:117211. [PMID: 36657206 DOI: 10.1016/j.jenvman.2022.117211] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 12/21/2022] [Accepted: 12/31/2022] [Indexed: 06/17/2023]
Abstract
The sustainable and green treatment of landfill leachate (LL), produced by municipal solid waste, represents one of the most relevant challenges in the integrated waste management systems. Accordingly, in this work a green solution was investigated by coupling an innovative hybrid constructed wetland (HCW) to a solar photo-Fenton (SPF) process. A multiple layers HCW pilot plant including different medium substrates (sand, solid compost and carriers) and plant species (Phragmites australis, Arundo donax and A. plinii) was designed. The HCW was functionalised with compost tea solution to simultaneously provide high nutrient content for plants and increase the microorganism biodiversity. Process efficiency was investigated using different real LLs (young and mature) in terms of chemical oxygen demand (COD), nitrogen compounds, chlorides and metals. Removals in the range 75-95% were observed for all the parameters after ten days of leachate recirculation in the pilot plant. Subsequently, the SPF process was carried out in a raceway pond reactor (RPR) as polishing step, significantly improving COD removal (further 49%). HCW combined with SPF in RPR would allow to meet the corresponding limits according to the final use/fate of the effluent by modulating the main parameters of the process.
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Affiliation(s)
- Ivano Spiniello
- Department of Chemistry and Biology "A. Zambelli", University of Salerno, Via Giovanni Paolo II 132, 84084, Fisciano, SA, Italy
| | - Marco De Carluccio
- Water Science and Technology (WaSTe) Group, Department of Civil Engineering, University of Salerno, Via Giovanni Paolo II 132, 84084, Fisciano, SA, Italy
| | - Stefano Castiglione
- Department of Chemistry and Biology "A. Zambelli", University of Salerno, Via Giovanni Paolo II 132, 84084, Fisciano, SA, Italy
| | - Enzhe Amineva
- Department of Environmental Health & Safety, Ufa State Aviation Technical University, Marks 12, 450077, Ufa, Republic of Bashkortostan, Russian Federation
| | - Natalia Kostryukova
- Department of Environmental Health & Safety, Ufa State Aviation Technical University, Marks 12, 450077, Ufa, Republic of Bashkortostan, Russian Federation
| | - Angela Cicatelli
- Department of Chemistry and Biology "A. Zambelli", University of Salerno, Via Giovanni Paolo II 132, 84084, Fisciano, SA, Italy.
| | - Luigi Rizzo
- Water Science and Technology (WaSTe) Group, Department of Civil Engineering, University of Salerno, Via Giovanni Paolo II 132, 84084, Fisciano, SA, Italy.
| | - Francesco Guarino
- Department of Chemistry and Biology "A. Zambelli", University of Salerno, Via Giovanni Paolo II 132, 84084, Fisciano, SA, Italy
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Singh A, Dasauni K, KumarNailwal T, Nenavathu BP. Formulation of dual functional gCN/TeO 2-ZnO nanocomposites as a controlled release nanofertilizer and antibacterial agent. NANOTECHNOLOGY 2023; 34:155602. [PMID: 36715368 DOI: 10.1088/1361-6528/acb2d1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 01/13/2023] [Indexed: 06/18/2023]
Abstract
A simple cost-effective sono-chemical method was used for the synthesis of gCN/TeO2-ZnO ternary (2%, 5%, and 10%) nanocomposites, having crystallite size of 12 nm. FE-SEM and transmission electron microscopy images revealed the formation of core-shell type nanocomposites with an average size of 50 nm. Further,E. coliMTCC 443 strain is used as a model organism to study the antibacterial activity of the prepared nanocomposites, using disc diffusion method. Among all the concentrations, 2% gCN/TeO2-ZnO showed maximum zone of inhibition of 23 ± 0.10 mm and its antibacterial activity is like third-generation antibiotic cefotaxime. In addition, the prepared nanocomposites were used as nanofertilizer for the growth of gram seeds Chickpea (Cicer arietinum). The effect of nanocomposite concentration and its sterilising properties are studied on the rate of germination of Chickpea using bothin vitroandin vivostudies (pot study). The root length of the gCN/TeO2-ZnO treated plants showed increase in seed germination (3.30 cm) compared to untreated plants (3.22 cm). In addition, enhancement in the shoot length about 28% is noticed in pot studies, compared to control batch samples. The accumulation of nanomaterial in plant roots was confirmed using SEM-EDX and ICP-MS. Finally, a 14-day experiment was conducted to ascertain the role of gCN/TeO2-ZnO in the controlled release of nutrients from the synthesised nanofertilizer. Owing to its excellent water holding capacity, sterilizing properties, and low toxicity this material can be used as a growth promoter in plants.
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Affiliation(s)
- Aishwarya Singh
- Department of Applied Sciences and Humanities, Indira Gandhi Delhi Technical University for Women, Delhi, 110006, India
| | - Khushboo Dasauni
- Department of Biotechnology, Sir J. C Bose Technical Campus, Bhimtal, Kumaun University, Nainital, Uttarakhand, 263136, India
| | - Tapan KumarNailwal
- Department of Biotechnology, Sir J. C Bose Technical Campus, Bhimtal, Kumaun University, Nainital, Uttarakhand, 263136, India
| | - Bhavani Prasad Nenavathu
- Department of Applied Sciences and Humanities, Indira Gandhi Delhi Technical University for Women, Delhi, 110006, India
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Scala A, Loperto I, Triassi M, Improta G. Risk Factors Analysis of Surgical Infection Using Artificial Intelligence: A Single Center Study. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:10021. [PMID: 36011656 PMCID: PMC9408161 DOI: 10.3390/ijerph191610021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/08/2022] [Accepted: 08/12/2022] [Indexed: 06/15/2023]
Abstract
Background: Surgical site infections (SSIs) have a major role in the evolution of medical care. Despite centuries of medical progress, the management of surgical infection remains a pressing concern. Nowadays, the SSIs continue to be an important factor able to increase the hospitalization duration, cost, and risk of death, in fact, the SSIs are a leading cause of morbidity and mortality in modern health care. Methods: A study based on statistical test and logistic regression for unveiling the association between SSIs and different risk factors was carried out. Successively, a predictive analysis of SSIs on the basis of risk factors was performed. Results: The obtained data demonstrated that the level of surgery contamination impacts significantly on the infection rate. In addition, data also reveals that the length of postoperative hospital stay increases the rate of surgical infections. Finally, the postoperative length of stay, surgery department and the antibiotic prophylaxis with 2 or more antibiotics are a significant predictor for the development of infection. Conclusions: The data report that the type of surgery department and antibiotic prophylaxis there are a statistically significant predictor of SSIs. Moreover, KNN model better handle the imbalanced dataset (48 infected and 3983 healthy), observing highest accuracy value.
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Affiliation(s)
- Arianna Scala
- Department of Public Health, University of Naples “Federico II”, 80100 Naples, Italy
| | - Ilaria Loperto
- Department of Public Health, University of Naples “Federico II”, 80100 Naples, Italy
| | - Maria Triassi
- Department of Public Health, University of Naples “Federico II”, 80100 Naples, Italy
- Interdepartmental Center for Research in Health Care Management and Innovation in Health Care (CIRMIS), University of Naples “Federico II”, 80100 Naples, Italy
| | - Giovanni Improta
- Department of Public Health, University of Naples “Federico II”, 80100 Naples, Italy
- Interdepartmental Center for Research in Health Care Management and Innovation in Health Care (CIRMIS), University of Naples “Federico II”, 80100 Naples, Italy
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Chen KH, Nelson J. A scoping review of bryophyte microbiota: diverse microbial communities in small plant packages. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:4496-4513. [PMID: 35536989 DOI: 10.1093/jxb/erac191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 05/05/2022] [Indexed: 06/14/2023]
Abstract
Plant health depends not only on the condition of the plant itself but also on its diverse community of microbes, or microbiota. Just like the better-studied angiosperms, bryophytes (mosses, liverworts, and hornworts) harbor diverse communities of bacteria, archaea, fungi, and other microbial eukaryotes. Bryophytes are increasingly recognized as important model systems for understanding plant evolution, development, physiology, and symbiotic interactions. Much of the work on bryophyte microbiota in the past focused on specific symbiont types for each bryophyte group, but more recent studies are taking a broader view acknowledging the coexistence of diverse microbial communities in bryophytes. Therefore, this review integrates studies of bryophyte microbes from both perspectives to provide a holistic view of the existing research for each bryophyte group and on key themes. The systematic search also reveals the taxonomic and geographic biases in this field, including a severe under-representation of the tropics, very few studies on viruses or eukaryotic microbes beyond fungi, and a focus on mycorrhizal fungi studies in liverworts. Such gaps may have led to errors in conclusions about evolutionary patterns in symbiosis. This analysis points to a wealth of future research directions that promise to reveal how the distinct life cycles and physiology of bryophytes interact with their microbiota.
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Affiliation(s)
- Ko-Hsuan Chen
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Jessica Nelson
- Maastricht Science Programme, Maastricht University, Maastricht, The Netherlands
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Hussain S, Khan M, Sheikh TMM, Mumtaz MZ, Chohan TA, Shamim S, Liu Y. Zinc Essentiality, Toxicity, and Its Bacterial Bioremediation: A Comprehensive Insight. Front Microbiol 2022; 13:900740. [PMID: 35711754 PMCID: PMC9197589 DOI: 10.3389/fmicb.2022.900740] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 05/09/2022] [Indexed: 02/04/2023] Open
Abstract
Zinc (Zn) is one of the most abundantly found heavy metals in the Earth's crust and is reported to be an essential trace metal required for the growth of living beings, with it being a cofactor of major proteins, and mediating the regulation of several immunomodulatory functions. However, its essentiality also runs parallel to its toxicity, which is induced through various anthropogenic sources, constant exposure to polluted sites, and other natural phenomena. The bioavailability of Zn is attributable to various vegetables, beef, and dairy products, which are a good source of Zn for safe consumption by humans. However, conditions of Zn toxicity can also occur through the overdosage of Zn supplements, which is increasing at an alarming rate attributing to lack of awareness. Though Zn toxicity in humans is a treatable and non-life-threatening condition, several symptoms cause distress to human activities and lifestyle, including fever, breathing difficulty, nausea, chest pain, and cough. In the environment, Zn is generally found in soil and water bodies, where it is introduced through the action of weathering, and release of industrial effluents, respectively. Excessive levels of Zn in these sources can alter soil and aquatic microbial diversity, and can thus affect the bioavailability and absorption of other metals as well. Several Gram-positive and -negative species, such as Bacillus sp., Staphylococcus sp., Streptococcus sp., and Escherichia coli, Pseudomonas sp., Klebsiella sp., and Enterobacter sp., respectively, have been reported to be promising agents of Zn bioremediation. This review intends to present an overview of Zn and its properties, uses, bioavailability, toxicity, as well as the major mechanisms involved in its bioremediation from polluted soil and wastewaters.
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Affiliation(s)
- Sarfraz Hussain
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, China
| | - Maryam Khan
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore, Pakistan
| | - Taha Majid Mahmood Sheikh
- Institute of Plant Protection, Jiangsu Academy of Agriculture Sciences, Nanjing, China,*Correspondence: Taha Majid Mahmood Sheikh,
| | - Muhammad Zahid Mumtaz
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore, Pakistan
| | - Talha Ali Chohan
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore, Pakistan
| | - Saba Shamim
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore, Pakistan,Saba Shamim,
| | - Yuhong Liu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, China,Yuhong Liu,
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Ali S, Tyagi A, Mushtaq M, Al-Mahmoudi H, Bae H. Harnessing plant microbiome for mitigating arsenic toxicity in sustainable agriculture. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 300:118940. [PMID: 35122918 DOI: 10.1016/j.envpol.2022.118940] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 01/08/2022] [Accepted: 01/30/2022] [Indexed: 06/14/2023]
Abstract
Heavy metal toxicity has become an impediment to agricultural productivity, which presents major human health concerns in terms of food safety. Among them, arsenic (As) a non-essential heavy metal has gained worldwide attention because of its noxious effects on agriculture and public health. The increasing rate of global warming and anthropogenic activities have promptly exacerbated As levels in the agricultural soil, thereby causing adverse effects to crop genetic and phenotypic traits and rendering them vulnerable to other stresses. Conventional breeding and transgenic approaches have been widely adapted for producing heavy metal resilient crops; however, they are time-consuming and labor-intensive. Hence, finding new mitigation strategies for As toxicity would be a game-changer for sustainable agriculture. One such promising approach is harnessing plant microbiome in the era of 'omics' which is gaining prominence in recent years. The use of plant microbiome and their cocktails to combat As metal toxicity has gained widespread attention, because of their ability to metabolize toxic elements and offer an array of perquisites to host plants such as increased nutrient availability, stress resilience, soil fertility, and yield. A comprehensive understanding of below-ground plant-microbiome interactions and their underlying molecular mechanisms in exhibiting resilience towards As toxicity will help in identifying elite microbial communities for As mitigation. In this review, we have discussed the effect of As, their accumulation, transportation, signaling, and detoxification in plants. We have also discussed the role of the plant microbiome in mitigating As toxicity which has become an intriguing research frontier in phytoremediation. This review also provides insights on the advancements in constructing the beneficial synthetic microbial communities (SynComs) using microbiome engineering that will facilitate the development of the most advanced As remedial tool kit in sustainable agriculture.
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Affiliation(s)
- Sajad Ali
- Department of Biotechnology, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, Republic of Korea
| | - Anshika Tyagi
- Department of Biotechnology, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, Republic of Korea
| | | | - Henda Al-Mahmoudi
- Directorate of Programs, International Center for Biosaline Agriculture, Dubai, United Arab Emirates
| | - Hanhong Bae
- Department of Biotechnology, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, Republic of Korea.
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Cepoi L, Zinicovscaia I, Valuta A, Codreanu L, Rudi L, Chiriac T, Yushin N, Grozdov D, Peshkova A. Peculiarities of the Edaphic Cyanobacterium Nostoc linckia Culture Response and Heavy Metal Accumulation from Copper-Containing Multimetal Systems. TOXICS 2022; 10:toxics10030113. [PMID: 35324738 PMCID: PMC8950056 DOI: 10.3390/toxics10030113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 02/14/2022] [Accepted: 02/24/2022] [Indexed: 11/16/2022]
Abstract
Soil and water pollution is a major problem that has a negative impact on ecosystems and human health in particular. In the bioremediation processes, the application of photosynthetic microorganisms, including cyanobacteria, is a direction of action addressed with increasing frequency in the context of further development and improvement of environmentally friendly techniques needed for detoxification of soils and waters polluted with low concentrations of toxic elements, since they pose a challenge for traditional treatment methods. In the present study, the removal of copper and other metal ions from multielement systems by three generations of Nostoc linckia is discussed. Changes in the biochemical composition of the nostoc biomass, which accumulates metal ions, were monitored. Neutron activation analysis was applied to assess Cu, Fe, Ni, and Zn accumulation by biomass, as well as to determine the biochemical composition of biomass after specific biochemical methods were used. The capacity of the accumulation of copper and other metal ions from multi-elemental systems by cyanobacteria Nostoc linckia was high and increased over two cycles of biomass growth in the systems Cu-Fe-Ni and Cu-Fe-Zn and over three cycles in Cu-Fe and Cu-Fe-Ni-Zn systems. It constituted 1720–10,600 µg metal/g depending on the system and cycle of cultivation. The accumulation of Fe, Ni, and Zn also increased over the generations of nostoc. The process of metal accumulation was demonstrated by a significant change in the biomass biochemical composition. Cyanobacteria Nostoc linckia possess a pronounced capacity of copper and other metal ion accumulation from multimetal systems and showed an increased resistance in environments polluted with heavy metals.
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Affiliation(s)
- Liliana Cepoi
- Institute of Microbiology and Biotechnology, 1, Academiei Str., 2028MD Chisinau, Moldova; (L.C.); (A.V.); (L.C.); (L.R.); (T.C.)
| | - Inga Zinicovscaia
- Joint Institute for Nuclear Research, 6 Joliot-Curie Str., 1419890 Dubna, Russia; (N.Y.); (D.G.); (A.P.)
- Department of Nuclear Physics, Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering, 30 Reactorului Str. MG-6, 077125 Magurele, Romania
- Correspondence: ; Tel.: +74-962-165-609
| | - Ana Valuta
- Institute of Microbiology and Biotechnology, 1, Academiei Str., 2028MD Chisinau, Moldova; (L.C.); (A.V.); (L.C.); (L.R.); (T.C.)
| | - Liviu Codreanu
- Institute of Microbiology and Biotechnology, 1, Academiei Str., 2028MD Chisinau, Moldova; (L.C.); (A.V.); (L.C.); (L.R.); (T.C.)
| | - Ludmila Rudi
- Institute of Microbiology and Biotechnology, 1, Academiei Str., 2028MD Chisinau, Moldova; (L.C.); (A.V.); (L.C.); (L.R.); (T.C.)
| | - Tatiana Chiriac
- Institute of Microbiology and Biotechnology, 1, Academiei Str., 2028MD Chisinau, Moldova; (L.C.); (A.V.); (L.C.); (L.R.); (T.C.)
| | - Nikita Yushin
- Joint Institute for Nuclear Research, 6 Joliot-Curie Str., 1419890 Dubna, Russia; (N.Y.); (D.G.); (A.P.)
| | - Dmitrii Grozdov
- Joint Institute for Nuclear Research, 6 Joliot-Curie Str., 1419890 Dubna, Russia; (N.Y.); (D.G.); (A.P.)
| | - Alexandra Peshkova
- Joint Institute for Nuclear Research, 6 Joliot-Curie Str., 1419890 Dubna, Russia; (N.Y.); (D.G.); (A.P.)
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Effects of Compost Amendment on Glycophyte and Halophyte Crops Grown on Saline Soils: Isolation and Characterization of Rhizobacteria with Plant Growth Promoting Features and High Salt Resistance. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11052125] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Soil salinization and desertification due to climate change are the most relevant challenges for the agriculture of the 21st century. Soil compost amendment and plant growth promoting rhizobacteria (PGP-R) are valuable tools to mitigate salinization and desertification impacts on agricultural soils. Selection of novel halo/thermo-tolerant bacteria from the rhizosphere of glicophytes and halophytes, grown on soil compost amended and watered with 150/300 mM NaCl, was the main objective of our study. Beneficial effects on the biomass, well-being and resilience, exerted on the assayed crops (maize, tomato, sunflower and quinoa), were clearly observable when soils were amended with 20% compost despite the very high soil electric conductivity (EC). Soil compost amendment not only was able to increase crop growth and biomass, but also their resilience to the stress caused by very high soil EC (up to 20 dS m−1). Moreover, compost amendment has proved itself a valuable source of highly halo-(4.0 M NaCl)/thermo tolerant rhizobacteria (55 °C), showing typical PGP features. Among the 13 rhizobacterial isolates, molecularly and biochemically characterized, two bacterial strains showed several biochemical PGP features. The use of compost is growing all around the world reducing considerably for farmers soil fertilization costs. In fact, only in Italy its utilization has ensured, in the last years, a saving of 650 million euro for the farmers, without taking into account the environment and human health benefits. Furthermore, the isolation of halo/thermo-tolerant PGPR strains and their use will allow the recovery and cultivation of hundreds of thousands of hectares of saline and arid soils now unproductive, making agriculture more respectful of agro-ecosystems also in view of upcoming climate change.
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