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Ghareeb RY, Jaremko M, Abdelsalam NR, Abdelhamid MMA, El-Argawy E, Ghozlan MH. Biocontrol potential of endophytic fungi against phytopathogenic nematodes on potato (Solanum tuberosum L.). Sci Rep 2024; 14:15547. [PMID: 38969662 PMCID: PMC11229511 DOI: 10.1038/s41598-024-64056-x] [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] [Received: 09/12/2023] [Accepted: 06/04/2024] [Indexed: 07/07/2024] Open
Abstract
Root-knot nematodes (RKNs) are a vital pest that causes significant yield losses and economic damage to potato plants. The use of chemical pesticides to control these nematodes has led to environmental concerns and the development of resistance in the nematode populations. Endophytic fungi offer an eco-friendly alternative to control these pests and produce secondary metabolites that have nematicidal activity against RKNs. The objective of this study is to assess the efficacy of Aspergillus flavus (ON146363), an entophyte fungus isolated from Trigonella foenum-graecum seeds, against Meloidogyne incognita in filtered culture broth using GC-MS analysis. Among them, various nematicidal secondary metabolites were produced: Gadoleic acid, Oleic acid di-ethanolamide, Oleic acid, and Palmitic acid. In addition, biochemical compounds such as Gallic acid, Catechin, Protocatechuic acid, Esculatin, Vanillic acid, Pyrocatechol, Coumarine, Cinnamic acid, 4, 3-indol butyl acetic acid and Naphthyl acetic acid by HPLC. The fungus was identified through morphological and molecular analysis, including ITS 1-4 regions of ribosomal DNA. In vitro experiments showed that culture filtrate of A. flavus had a variable effect on reducing the number of egg hatchings and larval mortality, with higher concentrations showing greater efficacy than Abamectin. The fungus inhibited the development and multiplication of M. incognita in potato plants, reducing the number of galls and eggs by 90% and 89%, respectively. A. flavus increased the activity of defense-related enzymes Chitinas, Catalyse, and Peroxidase after 15, 45, and 60 days. Leaching of the concentrated culture significantly reduced the second juveniles' stage to 97% /250 g soil and decreased the penetration of nematodes into the roots. A. flavus cultural filtrates via soil spraying improved seedling growth and reduced nematode propagation, resulting in systemic resistance to nematode infection. Therefore, A. flavus can be an effective biological control agent for root-knot nematodes in potato plants. This approach provides a sustainable solution for farmers and minimizes the environmental impact.
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Affiliation(s)
- Rehab Y Ghareeb
- Plant Protection and Biomolecular Diagnosis Department, Arid Lands Cultivation Research Institute (ALCRI), City of Scientific Research and Technological Applications (SRTA-City), Alexandria, Egypt.
| | - Mariusz Jaremko
- Division of Biological and Environmental Sciences and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), 23955, Thuwal, Saudi Arabia
| | - Nader R Abdelsalam
- Agricultural Botany Department, Faculty of Agriculture (Saba Basha), Alexandria University, Alexandria, 21531, Egypt
| | - Mohamed M A Abdelhamid
- Agricultural Botany Department, Faculty of Agriculture (Saba Basha), Alexandria University, Alexandria, 21531, Egypt
| | - Eman El-Argawy
- Department of Plant Pathology, Faculty of Agriculture, Damanhour University, Damanhour, Egypt
| | - Mahmoud H Ghozlan
- Department of Plant Pathology, Faculty of Agriculture, Damanhour University, Damanhour, Egypt
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Raruang Y, Omolehin O, Hu D, Wei Q, Promyou S, Parekattil LJ, Rajasekaran K, Cary JW, Wang K, Chen ZY. Targeting the Aspergillus flavus p2c gene through host-induced gene silencing reduces A. flavus infection and aflatoxin contamination in transgenic maize. FRONTIERS IN PLANT SCIENCE 2023; 14:1150086. [PMID: 37229129 PMCID: PMC10203651 DOI: 10.3389/fpls.2023.1150086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 04/11/2023] [Indexed: 05/27/2023]
Abstract
Aspergillus flavus is an opportunistic fungal pathogen that infects maize and produces aflatoxins. Using biocontrol or developing resistant cultivars to reduce aflatoxin contamination has only achieved limited success. Here, the A. flavus polygalacturonase gene (p2c) was targeted for suppression through host-induced gene silencing (HIGS) to reduce aflatoxin contamination in maize. An RNAi vector carrying a portion of the p2c gene was constructed and transformed into maize B104. Thirteen out of fifteen independent transformation events were confirmed to contain p2c. The T2 generation kernels containing the p2c transgene had less aflatoxin than those without the transgene in six out of eleven events we examined. Homozygous T3 transgenic kernels from four events produced significantly less aflatoxins (P ≤ 0.02) than the kernels from the null or B104 controls under field inoculation conditions. The F1 kernels from the crosses between six elite inbred lines with P2c5 and P2c13 also supported significantly less aflatoxins (P ≤ 0.02) than those from the crosses with null plants. The reduction in aflatoxin ranged from 93.7% to 30.3%. Transgenic leaf (T0 and T3) and kernel tissues (T4) were also found to have significantly higher levels of p2c gene-specific small RNAs. Further, homozygous transgenic maize kernels had significantly less fungal growth (27~40 fold) than the null control kernels 10 days after fungal inoculation in the field. The calculated suppression of p2c gene expression based on RNAseq data was 57.6% and 83.0% in P2c5 and P2c13 events, respectively. These results indicate clearly that the reduced aflatoxin production in the transgenic kernels is due to RNAi-based suppression of p2c expression, which results in reduced fungal growth and toxin production.
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Affiliation(s)
- Yenjit Raruang
- Department of Plant Pathology and Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, LA, United States
| | - Olanike Omolehin
- Department of Plant Pathology and Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, LA, United States
| | - Dongfang Hu
- Department of Plant Pathology and Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, LA, United States
| | - Qijian Wei
- Food and Feed Safety Research Unit, United States Department of Agriculture – Agricultural Research Service, Southern Regional Research Center, New Orleans, LA, United States
| | - Surassawadee Promyou
- Faculty of Natural Resources and Agro-Industry, Kasetsart University, Sakonnakhon, Thailand
| | - Lidiya J. Parekattil
- Department of Plant Pathology and Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, LA, United States
| | - Kanniah Rajasekaran
- Food and Feed Safety Research Unit, United States Department of Agriculture – Agricultural Research Service, Southern Regional Research Center, New Orleans, LA, United States
| | - Jeffrey W. Cary
- Food and Feed Safety Research Unit, United States Department of Agriculture – Agricultural Research Service, Southern Regional Research Center, New Orleans, LA, United States
| | - Kan Wang
- Department of Agronomy, Iowa State University, Ames, IA, United States
| | - Zhi-Yuan Chen
- Department of Plant Pathology and Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, LA, United States
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Liu S, Wang J, Guo N, Sun H, Ma H, Zhang H, Shi J. Talaromyces funiculosus, a Novel Causal Agent of Maize Ear Rot and Its Sensitivity to Fungicides. PLANT DISEASE 2021; 105:3978-3984. [PMID: 34156277 DOI: 10.1094/pdis-04-21-0686-re] [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: 06/13/2023]
Abstract
Ear rot is one of the most prevalent and destructive diseases of maize. During field surveys, it was found that a Penicillium ear rot broke out in some areas of Shanxi, Shaanxi, Hebei, and Tianjin in China, with an incidence of 3 to 90%. A Penicillium sp. was isolated from diseased kernels covered with greyish green mold, and three isolates were identified by morphologic and molecular characteristics. The pathogenicity of isolate ZBS205 to maize ears was further determined by artificial inoculation in a field. Furthermore, the sensitivity of isolate ZBS205 against six commonly used fungicides was also evaluated. According to macro- and micromorphologic characteristics, isolate ZBS205 was generally identical to Talaromyces funiculosus (teleomorph of Penicillium funiculosum). The partial gene sequences of the nuclear ribosomal ITS1-5.8S-ITS2 (ITS) region, β-tubulin, putative ribosome biogenesis protein (Tsr1), and the second largest subunit of the RNA polymerase II (RPB2) from isolates ZBS205, D49-1, and S73-1 showed the highest nucleotide identity to T. funiculosus strain X33, and the phylogenetic analysis conducted by the neighbor-joining method with the combined data of the four genes demonstrated that these three isolates clustered with T. funiculosus strain X33. These results suggested that the fungus isolated from diseased maize kernels was T. funiculosus. Pathogenicity testing showed that the T. funiculosus isolate ZBS205 was pathogenic to maize ears, which showed symptoms of rotted cob and deteriorated kernels. This is the first report of T. funiculosus as the definitive pathogen causing maize ear rot. The result of fungal sensitivity against fungicides showed that pyraclostrobin exhibited the highest toxicity to mycelial growth and could be used as a candidate agent for the prevention and control of T. funiculosus ear rot. The results of the present study provide a basis for understanding ear rot caused by T. funiculosus, and they should play an important role in disease management.
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Affiliation(s)
- Shusen Liu
- Plant Protection Institute, Hebei Academy of Agricultural and Forestry Sciences, IPM (Integrated Pest Management) Centre of Hebei Province; Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture and Rural Affairs, Baoding 071000, China
| | - Jinhui Wang
- College of Plant Protection, Hebei Agricultural University, Baoding 071001, China
| | - Ning Guo
- Plant Protection Institute, Hebei Academy of Agricultural and Forestry Sciences, IPM (Integrated Pest Management) Centre of Hebei Province; Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture and Rural Affairs, Baoding 071000, China
| | - Hua Sun
- Plant Protection Institute, Hebei Academy of Agricultural and Forestry Sciences, IPM (Integrated Pest Management) Centre of Hebei Province; Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture and Rural Affairs, Baoding 071000, China
| | - Hongxia Ma
- Plant Protection Institute, Hebei Academy of Agricultural and Forestry Sciences, IPM (Integrated Pest Management) Centre of Hebei Province; Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture and Rural Affairs, Baoding 071000, China
| | - Haijian Zhang
- Plant Protection Institute, Hebei Academy of Agricultural and Forestry Sciences, IPM (Integrated Pest Management) Centre of Hebei Province; Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture and Rural Affairs, Baoding 071000, China
| | - Jie Shi
- Plant Protection Institute, Hebei Academy of Agricultural and Forestry Sciences, IPM (Integrated Pest Management) Centre of Hebei Province; Key Laboratory of IPM on Crops in Northern Region of North China, Ministry of Agriculture and Rural Affairs, Baoding 071000, China
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Shen Y, Nie J, Kuang L, Zhang J, Li H. DNA sequencing, genomes and genetic markers of microbes on fruits and vegetables. Microb Biotechnol 2020; 14:323-362. [PMID: 32207561 PMCID: PMC7936329 DOI: 10.1111/1751-7915.13560] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/01/2020] [Accepted: 03/02/2020] [Indexed: 12/20/2022] Open
Abstract
The development of DNA sequencing technology has provided an effective method for studying foodborne and phytopathogenic microorganisms on fruits and vegetables (F & V). DNA sequencing has successfully proceeded through three generations, including the tens of operating platforms. These advances have significantly promoted microbial whole‐genome sequencing (WGS) and DNA polymorphism research. Based on genomic and regional polymorphisms, genetic markers have been widely obtained. These molecular markers are used as targets for PCR or chip analyses to detect microbes at the genetic level. Furthermore, metagenomic analyses conducted by sequencing the hypervariable regions of ribosomal DNA (rDNA) have revealed comprehensive microbial communities in various studies on F & V. This review highlights the basic principles of three generations of DNA sequencing, and summarizes the WGS studies of and available DNA markers for major bacterial foodborne pathogens and phytopathogenic fungi found on F & V. In addition, rDNA sequencing‐based bacterial and fungal metagenomics are summarized under three topics. These findings deepen the understanding of DNA sequencing and its application in studies of foodborne and phytopathogenic microbes and shed light on strategies for the monitoring of F & V microbes and quality control.
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Affiliation(s)
- Youming Shen
- Institute of Pomology, Chinese Academy of Agricultural Sciences/Laboratory of Quality & Safety Risk Assessment for Fruit (Xingcheng), Ministry of Agriculture and Rural Affairs/Quality Inspection and Test Center for Fruit and Nursery Stocks (Xingcheng), Ministry of Agriculture and Rural Affairs, Xingcheng, 125100, China
| | - Jiyun Nie
- Institute of Pomology, Chinese Academy of Agricultural Sciences/Laboratory of Quality & Safety Risk Assessment for Fruit (Xingcheng), Ministry of Agriculture and Rural Affairs/Quality Inspection and Test Center for Fruit and Nursery Stocks (Xingcheng), Ministry of Agriculture and Rural Affairs, Xingcheng, 125100, China.,College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Lixue Kuang
- Institute of Pomology, Chinese Academy of Agricultural Sciences/Laboratory of Quality & Safety Risk Assessment for Fruit (Xingcheng), Ministry of Agriculture and Rural Affairs/Quality Inspection and Test Center for Fruit and Nursery Stocks (Xingcheng), Ministry of Agriculture and Rural Affairs, Xingcheng, 125100, China
| | - Jianyi Zhang
- Institute of Pomology, Chinese Academy of Agricultural Sciences/Laboratory of Quality & Safety Risk Assessment for Fruit (Xingcheng), Ministry of Agriculture and Rural Affairs/Quality Inspection and Test Center for Fruit and Nursery Stocks (Xingcheng), Ministry of Agriculture and Rural Affairs, Xingcheng, 125100, China
| | - Haifei Li
- Institute of Pomology, Chinese Academy of Agricultural Sciences/Laboratory of Quality & Safety Risk Assessment for Fruit (Xingcheng), Ministry of Agriculture and Rural Affairs/Quality Inspection and Test Center for Fruit and Nursery Stocks (Xingcheng), Ministry of Agriculture and Rural Affairs, Xingcheng, 125100, China
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A Polyphasic Approach Aids Early Detection of Potentially Toxigenic Aspergilli in Soil. Microorganisms 2019; 7:microorganisms7090300. [PMID: 31470555 PMCID: PMC6781248 DOI: 10.3390/microorganisms7090300] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 08/24/2019] [Accepted: 08/26/2019] [Indexed: 11/16/2022] Open
Abstract
Key chili and maize growing areas of Pakistan were selected for a focused baseline study of the levels of Aspergillus spp. Investigations were undertaken using a combination of molecular and culture-based techniques. Samples investigated included soil samples, one-year-old corn cobs, and fresh chili from selected locations. Aspergillus strains obtained from corn cobs were screened using coconut milk agar, resulting in one strain that was positive for aflatoxin production. Whole genome sequencing (WGS) with low coverage techniques were employed to screen the isolates for differences in the ribosomal RNA gene cluster and mitochondrial genome, with the aflatoxigenic strain proving to have a distinctive profile. Finally, strains were subjected to matrix-assisted laser-desorption and ionization time-of-flight mass spectrometry (MALDI-ToF-MS) in order to obtain a proteomic ‘fingerprint’ which was used to distinguish the aflatoxigenic strain from the other isolates. The next generation sequencing (NGS) study was broadened to incorporate metabarcoding with ITS rRNA for determining the microbial biodiversity of the soil samples and presumptive screening for the presence of aflatoxigenic strains. Using information gleaned from the WGS results, a putative aflatoxigenic operational taxonomic unit (OTU) was observed in four of the 15 soil samples screened by metabarcoding. This method may have beneficial applications in early detection and surveillance programs in agricultural soils and commodities.
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Mitema A, Okoth S, Rafudeen SM. The Development of a qPCR Assay to Measure Aspergillus flavus Biomass in Maize and the Use of a Biocontrol Strategy to Limit Aflatoxin Production. Toxins (Basel) 2019; 11:toxins11030179. [PMID: 30934573 PMCID: PMC6468655 DOI: 10.3390/toxins11030179] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 03/14/2019] [Accepted: 03/18/2019] [Indexed: 01/10/2023] Open
Abstract
Aspergillus flavus colonisation of maize can produce mycotoxins that are detrimental to both human and animal health. Screening of maize lines, resistant to A. flavus infection, together with a biocontrol strategy, could help minimize subsequent aflatoxin contamination. We developed a qPCR assay to measure A. flavus biomass and showed that two African maize lines, GAF4 and KDV1, had different fungal loads for the aflatoxigenic isolate (KSM014), fourteen days after infection. The qPCR assay revealed no significant variation in A. flavus biomass between diseased and non-diseased maize tissues for GAF4, while KDV1 had a significantly higher A. flavus biomass (p < 0.05) in infected shoots and roots compared to the control. The biocontrol strategy using an atoxigenic isolate (KSM012) against the toxigenic isolate (KSM014), showed aflatoxin production inhibition at the co-infection ratio, 50:50 for both maize lines (KDV1 > 99.7% and GAF ≥ 69.4%), as confirmed by bioanalytical techniques. As far as we are aware, this is the first report in Kenya where the biomass of A. flavus from maize tissue was detected and quantified using a qPCR assay. Our results suggest that maize lines, which have adequate resistance to A. flavus, together with the appropriate biocontrol strategy, could limit outbreaks of aflatoxicoses.
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Affiliation(s)
- Alfred Mitema
- Plant Stress Laboratory 204/207, Department of Molecular and Cell Biology, MCB Building, Upper Campus, University of Cape Town, Private bag X3, Rondebosch, Cape Town 7701, South Africa.
- Department of Botany, School of Biological Sciences, University of Nairobi, P.O. Box 30197, Nairobi 00100, Kenya.
| | - Sheila Okoth
- Department of Botany, School of Biological Sciences, University of Nairobi, P.O. Box 30197, Nairobi 00100, Kenya.
| | - Suhail M Rafudeen
- Plant Stress Laboratory 204/207, Department of Molecular and Cell Biology, MCB Building, Upper Campus, University of Cape Town, Private bag X3, Rondebosch, Cape Town 7701, South Africa.
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Eshelli M, Qader MM, Jambi EJ, Hursthouse AS, Rateb ME. Current Status and Future Opportunities of Omics Tools in Mycotoxin Research. Toxins (Basel) 2018; 10:E433. [PMID: 30373184 PMCID: PMC6267353 DOI: 10.3390/toxins10110433] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 10/20/2018] [Accepted: 10/24/2018] [Indexed: 12/12/2022] Open
Abstract
Mycotoxins are toxic secondary metabolites of low molecular weight produced by filamentous fungi, such as Aspergillus, Fusarium, and Penicillium spp. Mycotoxins are natural contaminants of agricultural commodities and their prevalence may increase due to global warming. Dangerous mycotoxins cause a variety of health problems not only for humans, but also for animals. For instance, they possess carcinogenic, immunosuppressive, hepatotoxic, nephrotoxic, and neurotoxic effects. Hence, various approaches have been used to assess and control mycotoxin contamination. Significant challenges still exist because of the complex heterogeneous nature of food composition. The potential of combined omics approaches such as metabolomics, genomics, transcriptomics, and proteomics would contribute to our understanding about pathogen fungal crosstalk as well as strengthen our ability to identify, isolate, and characterise mycotoxins pre and post-harvest. Multi-omics approaches along with advanced analytical tools and chemometrics provide a complete annotation of such metabolites produced before/during the contamination of crops. We have assessed the merits of these individual and combined omics approaches and their promising applications to mitigate the issue of mycotoxin contamination. The data included in this review focus on aflatoxin, ochratoxin, and patulin and would be useful as benchmark information for future research.
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Affiliation(s)
- Manal Eshelli
- School of Computing, Engineering, & Physical Sciences, University of the West of Scotland, Paisley PA1 2BE, UK.
- Food Science and Technology Department, Faculty of Agriculture, University of Tripoli, Tripoli 13538, Libya.
| | - M Mallique Qader
- School of Computing, Engineering, & Physical Sciences, University of the West of Scotland, Paisley PA1 2BE, UK.
- National Institute of Fundamental Studies, Hantana Road, Kandy 20000, Sri Lanka.
| | - Ebtihaj J Jambi
- Biochemistry Department, Faculty of Science, Girls Section, King Abdulaziz University, Jeddah 21551, Saudi Arabia.
| | - Andrew S Hursthouse
- School of Computing, Engineering, & Physical Sciences, University of the West of Scotland, Paisley PA1 2BE, UK.
| | - Mostafa E Rateb
- School of Computing, Engineering, & Physical Sciences, University of the West of Scotland, Paisley PA1 2BE, UK.
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Gilbert MK, Mack BM, Moore GG, Downey DL, Lebar MD, Joardar V, Losada L, Yu J, Nierman WC, Bhatnagar D. Whole genome comparison of Aspergillus flavus L-morphotype strain NRRL 3357 (type) and S-morphotype strain AF70. PLoS One 2018; 13:e0199169. [PMID: 29966003 PMCID: PMC6028093 DOI: 10.1371/journal.pone.0199169] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 06/01/2018] [Indexed: 01/03/2023] Open
Abstract
Aspergillus flavus is a saprophytic fungus that infects corn, peanuts, tree nuts and other agriculturally important crops. Once the crop is infected the fungus has the potential to secrete one or more mycotoxins, the most carcinogenic of which is aflatoxin. Aflatoxin contaminated crops are deemed unfit for human or animal consumption, which results in both food and economic losses. Within A. flavus, two morphotypes exist: the S strains (small sclerotia) and L strains (large sclerotia). Significant morphological and physiological differences exist between the two morphotypes. For example, the S-morphotypes produces sclerotia that are smaller (< 400 μm), greater in quantity, and contain higher concentrations of aflatoxin than the L-morphotypes (>400 μm). The morphotypes also differ in pigmentation, pH homeostasis in culture and the number of spores produced. Here we report the first full genome sequence of an A. flavus S morphotype, strain AF70. We provide a comprehensive comparison of the A. flavus S-morphotype genome sequence with a previously sequenced genome of an L-morphotype strain (NRRL 3357), including an in-depth analysis of secondary metabolic clusters and the identification SNPs within their aflatoxin gene clusters.
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Affiliation(s)
- Matthew K. Gilbert
- Food and Feed Safety Unit, USDA, New Orleans, Louisiana, United States of America
- * E-mail:
| | - Brian M. Mack
- Food and Feed Safety Unit, USDA, New Orleans, Louisiana, United States of America
| | - Geromy G. Moore
- Food and Feed Safety Unit, USDA, New Orleans, Louisiana, United States of America
| | - Darlene L. Downey
- Food and Feed Safety Unit, USDA, New Orleans, Louisiana, United States of America
| | - Matthew D. Lebar
- Food and Feed Safety Unit, USDA, New Orleans, Louisiana, United States of America
| | - Vinita Joardar
- The J. Craig Venter Institute, Rockville, Maryland, United States of America
| | - Liliana Losada
- The J. Craig Venter Institute, Rockville, Maryland, United States of America
| | - JiuJiang Yu
- Food Quality Laboratory, USDA, Beltsville, Maryland, United States of America
| | - William C. Nierman
- The J. Craig Venter Institute, Rockville, Maryland, United States of America
| | - Deepak Bhatnagar
- Food and Feed Safety Unit, USDA, New Orleans, Louisiana, United States of America
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Bhatnagar D, Rajasekaran K, Gilbert M, Cary J, Magan N. Advances in molecular and genomic research to safeguard food and feed supply from aflatoxin contamination. WORLD MYCOTOXIN J 2018. [DOI: 10.3920/wmj2017.2283] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Worldwide recognition that aflatoxin contamination of agricultural commodities by the fungus Aspergillus flavus is a global problem has significantly benefitted from global collaboration for understanding the contaminating fungus, as well as for developing and implementing solutions against the contamination. The effort to address this serious food and feed safety issue has led to a detailed understanding of the taxonomy, ecology, physiology, genomics and evolution of A. flavus, as well as strategies to reduce or control pre-harvest aflatoxin contamination, including (1) biological control, using atoxigenic aspergilli, (2) proteomic and genomic analyses for identifying resistance factors in maize as potential breeding markers to enable development of resistant maize lines, and (3) enhancing host-resistance by bioengineering of susceptible crops, such as cotton, maize, peanut and tree nuts. A post-harvest measure to prevent the occurrence of aflatoxin contamination in storage is also an important component for reducing exposure of populations worldwide to aflatoxins in food and feed supplies. The effect of environmental changes on aflatoxin contamination levels has recently become an important aspect for study to anticipate future contamination levels. The ability of A. flavus to produce dozens of secondary metabolites, in addition to aflatoxins, has created a new avenue of research for understanding the role these metabolites play in the survival and biodiversity of this fungus. The understanding of A. flavus, the aflatoxin contamination problem, and control measures to prevent the contamination has become a unique example for an integrated approach to safeguard global food and feed safety.
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Affiliation(s)
- D. Bhatnagar
- US Department of Agriculture, Agricultural Research Service, 1100 Robert E. Lee Boulevard, New Orleans, LA 70124, USA
| | - K. Rajasekaran
- US Department of Agriculture, Agricultural Research Service, 1100 Robert E. Lee Boulevard, New Orleans, LA 70124, USA
| | - M. Gilbert
- US Department of Agriculture, Agricultural Research Service, 1100 Robert E. Lee Boulevard, New Orleans, LA 70124, USA
| | - J.W. Cary
- US Department of Agriculture, Agricultural Research Service, 1100 Robert E. Lee Boulevard, New Orleans, LA 70124, USA
| | - N. Magan
- Applied Mycology Group, Cranfield University, MK45 4DT, Cranfield, United Kingdom
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Zhang C, Selvaraj JN, Yang Q, Liu Y. A Survey of Aflatoxin-Producing Aspergillus sp. from Peanut Field Soils in Four Agroecological Zones of China. Toxins (Basel) 2017; 9:E40. [PMID: 28117685 PMCID: PMC5308272 DOI: 10.3390/toxins9010040] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 01/05/2017] [Accepted: 01/06/2017] [Indexed: 11/20/2022] Open
Abstract
Peanut pods are easily infected by aflatoxin-producing Aspergillus sp.ecies from field soil. To assess the aflatoxin-producing Aspergillus sp. in different peanut field soils, 344 aflatoxin-producing Aspergillus strains were isolated from 600 soil samples of four agroecological zones in China (the Southeast coastal zone (SEC), the Yangtze River zone (YZR), the Yellow River zone (YR) and the Northeast zone (NE)). Nearly 94.2% (324/344) of strains were A. flavus and 5.8% (20/344) of strains were A. parasiticus. YZR had the highest population density of Aspergillus sp. and positive rate of aflatoxin production in isolated strains (1039.3 cfu·g-1, 80.7%), the second was SEC (191.5 cfu·g-1, 48.7%), the third was YR (26.5 cfu·g-1, 22.7%), and the last was NE (2.4 cfu·g-1, 6.6%). The highest risk of AFB₁ contamination on peanut was in YZR which had the largest number of AFB₁ producing isolates in 1g soil, followed by SEC and YR, and the lowest was NE. The potential risk of AFB₁ contamination in peanuts can increase with increasing population density and a positive rate of aflatoxin-producing Aspergillus sp. in field soils, suggesting that reducing aflatoxigenic Aspergillus sp. in field soils could prevent AFB₁ contamination in peanuts.
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Affiliation(s)
- Chushu Zhang
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing 100193, China.
- Shandong Peanut Research Institute, Qingdao 266100, China.
| | - Jonathan Nimal Selvaraj
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing 100193, China.
| | - Qingli Yang
- Qingdao Agricultural University, Qingdao 266109, China.
| | - Yang Liu
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing 100193, China.
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