1
|
Dahab AA, Bayomy HM, El-Salam HSA, Almasoudi SE, Ozaybi NA, Mahmoud GA, Atteya AKG, El-Serafy RS. Seed Disinfection Treatments Minimized Microbial Load and Enhanced Nutritional Properties of Fenugreek Sprouts Which Alleviated Diabetes-Negative Disorders in Diabetic Rats. Nutrients 2024; 16:2635. [PMID: 39203772 PMCID: PMC11357563 DOI: 10.3390/nu16162635] [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: 06/28/2024] [Revised: 08/02/2024] [Accepted: 08/05/2024] [Indexed: 09/03/2024] Open
Abstract
Sprouts are an attractive food product that contains high amounts of nutritional substances and has pro-health features. Sprout consumption has strongly increased despite its potential risk to health due to its microbial load. Both the safety and shelf life of sprouts may be negatively affected by a high microbial load. To reduce the microbial contamination in sprouts before consumption, the initial microbial load on the seeds needs to be controlled. Many herbal sprouts have been recommended for diabetes, and fenugreek is one of these sprouts. Thus, the current experiment aimed at disinfecting fenugreek seeds using microwave (5, 10, and 20 s) and hot water (30, 45, and 60 s) treatments for different durations. The best-disinfected sprouts with the highest nutritional properties were used to evaluate their influence on streptozocin-induced diabetic rats in comparison with fenugreek seed feeding. Microwave treatments showed the highest sprout length, fresh weight, total free amino acids, antioxidants, reducing sugars, and total phenols. Additionally, microwave seed treatments showed the lowest bacteria and mold counts on sprouts produced relative to hot water treatments, and the best seed treatment was a microwave for 20 s, which gave the best values in this respect. Feeding diabetic rats with different fenugreek seeds or sprout rates (0, 5, 7.5, and 10% w/w) improved body weight, restricted the growth of glucose levels, lowered total cholesterol and triglycerides, and improved HDL compared with the positive control group, and fenugreek sprouts at higher rates showed the maximum improvements in blood glucose, total cholesterol, and triglycerides. Treating fenugreek seed with microwave radiation for 20 s to disinfect the seeds before sprouting is recommended for lowering the microbial load with optimum nutritional and antioxidant activity, and feeding diabetic rats with these sprouts at the rate of 7.5 and 10% had promising effects on hyperglycemia and associated disorders.
Collapse
Affiliation(s)
- Abeer A. Dahab
- Medicinal and Aromatic Plants Research Department, Horticulture Research Institute, Agricultural Research Center, Giza 12619, Egypt;
| | - Hala M. Bayomy
- Food Science and Nutrition Department, Faculty of Science, University of Tabuk, Tabuk 71491, Saudi Arabia; (H.M.B.); (S.E.A.); (N.A.O.)
| | - Hemat S. Abd El-Salam
- Medicinal and Aromatic Plants Research Department, Horticulture Research Institute, Agricultural Research Center, Giza 12619, Egypt;
| | - Seham E. Almasoudi
- Food Science and Nutrition Department, Faculty of Science, University of Tabuk, Tabuk 71491, Saudi Arabia; (H.M.B.); (S.E.A.); (N.A.O.)
| | - Nawal A. Ozaybi
- Food Science and Nutrition Department, Faculty of Science, University of Tabuk, Tabuk 71491, Saudi Arabia; (H.M.B.); (S.E.A.); (N.A.O.)
| | - Gehan A. Mahmoud
- Fruit Crops Handling Research Department, Horticulture Research Institute, Agricultural Research Center, Giza 12619, Egypt;
| | - Amira K. G. Atteya
- Horticulture Department, Faculty of Agriculture, Damanhour University, Damanhour 22516, Egypt;
| | - Rasha S. El-Serafy
- Horticulture Department, Faculty of Agriculture, Tanta University, Tanta 31527, Egypt
| |
Collapse
|
2
|
Baldino KD, Scott JC, Dung JKS. The Alternative Host with the Most: Understanding the Ecology of Xanthomonas hortorum pv. carotae on Noncarrot Crops in Central Oregon. PLANT DISEASE 2024; 108:1755-1761. [PMID: 38213121 DOI: 10.1094/pdis-08-23-1631-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2024]
Abstract
Bacterial blight of carrot, caused by Xanthomonas hortorum pv. carotae (Xhc), is an economically important disease in carrot (Daucus carota subsp. sativus) seed production. The objectives of this study were to determine if Xhc was present on noncarrot crops grown in central Oregon and, if detected, evaluate its ability to colonize alternative hosts. Surveys of three carrot seed fields and adjacent fields of rye (Secale cereale), alfalfa (Medicago sativa), parsley root (Petroselinum crispum var. tuberosum), and Kentucky bluegrass (Poa pratensis) demonstrated that Xhc was present on noncarrot crops. Greenhouse experiments were conducted to determine the ability of Xhc to colonize crops cultivated in the region. Carrot, alfalfa, curly parsley (Petroselinum crispum), Kentucky bluegrass, mint (Mentha × piperita), parsley root, roughstalk bluegrass (Poa trivialis), and wheat (Triticum aestivum) plants were spray-inoculated with Xhc and destructively sampled at 1, 7, 14, and 28 or 25 days post-inoculation. Xhc populations were quantified using viability quantitative PCR and dilution plating. A significant (P ≤ 0.03) effect of crop was observed at 1, 14, and 28 or 25 days in both experiments. While carrot hosted the most Xhc at the final timepoint, other crops supported epiphytic Xhc populations including wheat and both bluegrasses. Mint, parsley root, and alfalfa hosted the least Xhc. Bacterial blight symptoms were observed on carrots but not on noncarrot crops. This suggests that crops grown in central Oregon have the potential to be asymptomatically colonized by Xhc and may serve as reservoirs of the pathogen in carrot seed production systems.
Collapse
Affiliation(s)
- Katelyn D Baldino
- Oregon State University, Central Oregon Agriculture Research and Extension Center, Madras, OR 97741
| | - Jeness C Scott
- Oregon State University, Central Oregon Agriculture Research and Extension Center, Madras, OR 97741
| | - Jeremiah K S Dung
- Oregon State University, Central Oregon Agriculture Research and Extension Center, Madras, OR 97741
| |
Collapse
|
3
|
Hakalová E, Tekielska DA, Wohlmuth J, Čechová J. Management of bacterial blight of carrots by phenolic compounds treatment. PLoS One 2024; 19:e0299105. [PMID: 38557606 PMCID: PMC10984397 DOI: 10.1371/journal.pone.0299105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Accepted: 02/05/2024] [Indexed: 04/04/2024] Open
Abstract
Bacterial blight is a serious disease of carrot production worldwide. Under favorable conditions, the causal organism Xanthomonas hortorum pv. carotae causes serious loss especially in seed production because of its seed-borne character. Unlike fungal diseases, the treatment of bacterial diseases is limited and methods such as hot water or sodium hypochlorite (bleach) treatment are mainly used by seed companies. Here, we compared the efficacy of hot water treatment, sodium hypochlorite treatment and treatment with three phenolic compounds-carvacrol, thymol and eugenol, to eliminate Xanthomonas growth in vitro and subsequently in vivo on seeds of Xhc low, medium and highly infested carrot seed lots. The complete elimination of Xhc from germinated plants was obtained only for Xhc low infested seed lot with 1% sodium hypochlorite and carvacrol solutions in concentrations of 0.0196%- 0.313%. The significant reduction of Xhc presence in germinated plants of Xhc medium infested seed lot was achieved with 1% sodium hypochlorite treatment and hot water treatment. However, hot water treatment resulted in a significant reduction of seed germination percentage as well. Considering the elimination of Xhc infection from germinated plants and the effect on seed germination and plant vigor, 0.0196% carvacrol solution was suggested as an alternative to 1% sodium hypochlorite treatment regarding additional costs related to the liquidation of used treated water and to hot water treatment that has been proved to be insufficient to obtain disease-free plants.
Collapse
Affiliation(s)
- Eliška Hakalová
- Mendeleum–Department of Genetics, Faculty of Horticulture, Mendel University in Brno, Lednice, Czech Republic
| | - Dorota A. Tekielska
- Mendeleum–Department of Genetics, Faculty of Horticulture, Mendel University in Brno, Lednice, Czech Republic
| | - Jan Wohlmuth
- Mendeleum–Department of Genetics, Faculty of Horticulture, Mendel University in Brno, Lednice, Czech Republic
| | - Jana Čechová
- Mendeleum–Department of Genetics, Faculty of Horticulture, Mendel University in Brno, Lednice, Czech Republic
| |
Collapse
|
4
|
Wang H, Wagnon R, Moreno D, Timilsina S, Jones J, Vallad G, Turechek WW. A Long-Amplicon Viability-qPCR Test for Quantifying Living Pathogens that Cause Bacterial Spot in Tomato Seed. PLANT DISEASE 2022; 106:1474-1485. [PMID: 34894749 DOI: 10.1094/pdis-11-21-2509-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Bacterial spot is one of the most serious diseases of tomato. It is caused by four species of Xanthomonas: X. euvesicatoria, X. gardneri, X. perforans, and X. vesicatoria. Contaminated or infected seed can be a major source of inoculum for this disease. The use of certified pathogen-free seed is one of the primary management practices to reduce the inoculum load in commercial production. Current seed testing protocols rely mainly on plating the seed extract and conventional PCR; however, the plating method cannot detect viable but nonculturable cells, and the conventional PCR assay has limited capability to differentiate DNA extracted from viable or dead bacterial cells. To improve the sensitivity and specificity of the tomato seed testing method for bacterial spot pathogens, a long-amplicon quantitative PCR (qPCR) assay coupled with propidium monoazide (PMA-qPCR) was developed to quantify selectively the four pathogenic Xanthomonas species in tomato seed. The optimized PMA-qPCR procedure was evaluated on pure bacterial suspensions, bacteria-spiked seed extracts, and seed extracts of inoculated and naturally infected seed. A crude DNA extraction protocol also was developed, and PMA-qPCR with crude bacterial DNA extracts resulted in accurate quantification of 104 to 108 CFU/ml of viable bacteria when mixed with dead cells at concentrations as high as 107 CFU/ml in the seed extracts. With DNA purified from concentrated seed extracts, the PMA-qPCR assay was able to detect DNA of the target pathogens in seed samples spiked with ≥75 CFU/ml (about 0.5 CFU/seed) of the viable pathogens. Latent class analysis of the inoculated and naturally infected seed samples showed that the PMA-qPCR assay had greater sensitivity than plating the seed extracts on the semiselective modified Tween Medium B and CKTM media for all four target species. Being much faster and more sensitive than dilution plating, the PMA-qPCR assay has potential to be used as a standalone tool or in combination with the plating method to improve tomato seed testing and advance the production of clean seed.
Collapse
Affiliation(s)
- Hehe Wang
- EDISTO Research and Education Center, Clemson University, Blackville, SC 29817
| | - Rieanna Wagnon
- EDISTO Research and Education Center, Clemson University, Blackville, SC 29817
| | - Daniela Moreno
- EDISTO Research and Education Center, Clemson University, Blackville, SC 29817
| | | | | | - Gary Vallad
- Gulf Coast Research and Education Center, University of Florida, Wimauma, FL 33598
| | | |
Collapse
|
5
|
Dia NC, Morinière L, Cottyn B, Bernal E, Jacobs J, Koebnik R, Osdaghi E, Potnis N, Pothier J. Xanthomonas hortorum - beyond gardens: Current taxonomy, genomics, and virulence repertoires. MOLECULAR PLANT PATHOLOGY 2022; 23:597-621. [PMID: 35068051 PMCID: PMC8995068 DOI: 10.1111/mpp.13185] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 12/27/2021] [Accepted: 12/28/2021] [Indexed: 05/02/2023]
Abstract
TAXONOMY Bacteria; Phylum Proteobacteria; Class Gammaproteobacteria; Order Lysobacterales (earlier synonym of Xanthomonadales); Family Lysobacteraceae (earlier synonym of Xanthomonadaceae); Genus Xanthomonas; Species X. hortorum; Pathovars: pv. carotae, pv. vitians, pv. hederae, pv. pelargonii, pv. taraxaci, pv. cynarae, and pv. gardneri. HOST RANGE Xanthomonas hortorum affects agricultural crops, and horticultural and wild plants. Tomato, carrot, artichoke, lettuce, pelargonium, ivy, and dandelion were originally described as the main natural hosts of the seven separate pathovars. Artificial inoculation experiments also revealed other hosts. The natural and experimental host ranges are expected to be broader than initially assumed. Additionally, several strains, yet to be assigned to a pathovar within X. hortorum, cause diseases on several other plant species such as peony, sweet wormwood, lavender, and oak-leaf hydrangea. EPIDEMIOLOGY AND CONTROL X. hortorum pathovars are mainly disseminated by infected seeds (e.g., X. hortorum pvs carotae and vitians) or cuttings (e.g., X. hortorum pv. pelargonii) and can be further dispersed by wind and rain, or mechanically transferred during planting and cultivation. Global trade of plants, seeds, and other propagating material constitutes a major pathway for their introduction and spread into new geographical areas. The propagules of some pathovars (e.g., X. horturum pv. pelargonii) are spread by insect vectors, while those of others can survive in crop residues and soils, and overwinter until the following growing season (e.g., X. hortorum pvs vitians and carotae). Control measures against X. hortorum pathovars are varied and include exclusion strategies (i.e., by using certification programmes and quarantine regulations) to multiple agricultural practices such as the application of phytosanitary products. Copper-based compounds against X. hortorum are used, but the emergence of copper-tolerant strains represents a major threat for their effective management. With the current lack of efficient chemical or biological disease management strategies, host resistance appears promising, but is not without challenges. The intrastrain genetic variability within the same pathovar poses a challenge for breeding cultivars with durable resistance. USEFUL WEBSITES https://gd.eppo.int/taxon/XANTGA, https://gd.eppo.int/taxon/XANTCR, https://gd.eppo.int/taxon/XANTPE, https://www.euroxanth.eu, http://www.xanthomonas.org, http://www.xanthomonas.org/dokuwiki.
Collapse
Affiliation(s)
- Nay C. Dia
- Environmental Genomics and Systems Biology Research GroupInstitute for Natural Resource SciencesZurich University of Applied SciencesWädenswilSwitzerland
- Molecular Plant BreedingInstitute of Agricultural SciencesETH ZurichZurichSwitzerland
| | - Lucas Morinière
- University of LyonUniversité Claude Bernard Lyon 1CNRSINRAEUMR Ecologie MicrobienneVilleurbanneFrance
| | - Bart Cottyn
- Plant Sciences UnitFlanders Research Institute for Agriculture, Fisheries and FoodMerelbekeBelgium
| | - Eduardo Bernal
- Department of Plant PathologyThe Ohio State UniversityColumbusOhioUSA
| | - Jonathan M. Jacobs
- Department of Plant PathologyThe Ohio State UniversityColumbusOhioUSA
- Infectious Diseases InstituteThe Ohio State UniversityColumbusOhioUSA
| | - Ralf Koebnik
- Plant Health Institute of MontpellierUniversity of Montpellier, CIRAD, INRAe, Institut Agro, IRDMontpellierFrance
| | - Ebrahim Osdaghi
- Department of Plant ProtectionCollege of AgricultureUniversity of TehranKarajIran
| | - Neha Potnis
- Department of Entomology and Plant PathologyAuburn UniversityAlabamaUSA
| | - Joël F. Pothier
- Environmental Genomics and Systems Biology Research GroupInstitute for Natural Resource SciencesZurich University of Applied SciencesWädenswilSwitzerland
| |
Collapse
|
6
|
Catara V, Cubero J, Pothier JF, Bosis E, Bragard C, Đermić E, Holeva MC, Jacques MA, Petter F, Pruvost O, Robène I, Studholme DJ, Tavares F, Vicente JG, Koebnik R, Costa J. Trends in Molecular Diagnosis and Diversity Studies for Phytosanitary Regulated Xanthomonas. Microorganisms 2021; 9:862. [PMID: 33923763 PMCID: PMC8073235 DOI: 10.3390/microorganisms9040862] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/10/2021] [Accepted: 04/12/2021] [Indexed: 11/17/2022] Open
Abstract
Bacteria in the genus Xanthomonas infect a wide range of crops and wild plants, with most species responsible for plant diseases that have a global economic and environmental impact on the seed, plant, and food trade. Infections by Xanthomonas spp. cause a wide variety of non-specific symptoms, making their identification difficult. The coexistence of phylogenetically close strains, but drastically different in their phenotype, poses an added challenge to diagnosis. Data on future climate change scenarios predict an increase in the severity of epidemics and a geographical expansion of pathogens, increasing pressure on plant health services. In this context, the effectiveness of integrated disease management strategies strongly depends on the availability of rapid, sensitive, and specific diagnostic methods. The accumulation of genomic information in recent years has facilitated the identification of new DNA markers, a cornerstone for the development of more sensitive and specific methods. Nevertheless, the challenges that the taxonomic complexity of this genus represents in terms of diagnosis together with the fact that within the same bacterial species, groups of strains may interact with distinct host species demonstrate that there is still a long way to go. In this review, we describe and discuss the current molecular-based methods for the diagnosis and detection of regulated Xanthomonas, taxonomic and diversity studies in Xanthomonas and genomic approaches for molecular diagnosis.
Collapse
Affiliation(s)
- Vittoria Catara
- Department of Agriculture, Food and Environment, University of Catania, 95125 Catania, Italy
| | - Jaime Cubero
- National Institute for Agricultural and Food Research and Technology (INIA), 28002 Madrid, Spain;
| | - Joël F. Pothier
- Environmental Genomics and Systems Biology Research Group, Institute for Natural Resource Sciences, Zurich University of Applied Sciences (ZHAW), 8820 Wädenswil, Switzerland;
| | - Eran Bosis
- Department of Biotechnology Engineering, ORT Braude College of Engineering, Karmiel 2161002, Israel;
| | - Claude Bragard
- UCLouvain, Earth & Life Institute, Applied Microbiology, 1348 Louvain-la-Neuve, Belgium;
| | - Edyta Đermić
- Department of Plant Pathology, Faculty of Agriculture, University of Zagreb, 10000 Zagreb, Croatia;
| | - Maria C. Holeva
- Benaki Phytopathological Institute, Scientific Directorate of Phytopathology, Laboratory of Bacteriology, GR-14561 Kifissia, Greece;
| | - Marie-Agnès Jacques
- IRHS, INRA, AGROCAMPUS-Ouest, Univ Angers, SFR 4207 QUASAV, 49071 Beaucouzé, France;
| | - Francoise Petter
- European and Mediterranean Plant Protection Organization (EPPO/OEPP), 75011 Paris, France;
| | - Olivier Pruvost
- CIRAD, UMR PVBMT, F-97410 Saint Pierre, La Réunion, France; (O.P.); (I.R.)
| | - Isabelle Robène
- CIRAD, UMR PVBMT, F-97410 Saint Pierre, La Réunion, France; (O.P.); (I.R.)
| | | | - Fernando Tavares
- CIBIO—Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO-Laboratório Associado, Universidade do Porto, 4485-661 Vairão, Portugal; or
- FCUP-Faculdade de Ciências, Departamento de Biologia, Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal
| | | | - Ralf Koebnik
- Plant Health Institute of Montpellier (PHIM), Univ Montpellier, Cirad, INRAe, Institut Agro, IRD, 34398 Montpellier, France;
| | - Joana Costa
- Centre for Functional Ecology-Science for People & the Planet, Department of Life Sciences, University of Coimbra, 300-456 Coimbra, Portugal
- Laboratory for Phytopathology, Instituto Pedro Nunes, 3030-199 Coimbra, Portugal
| |
Collapse
|
7
|
Palomo Gómez JL, Shima M, Monterde A, Navarro I, Barbé S, Marco-Noales E. First report of bacterial leaf blight caused by Xanthomonas hortorum pv. carotae on carrots in Spain. PLANT DISEASE 2021; 105:2712. [PMID: 33622058 DOI: 10.1094/pdis-11-20-2493-pdn] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In September 2019, symptoms resembling those of bacterial leaf blight were observed on carrot plants (Daucus carota L. subsp. sativus Hoffm.) cv. Romance cultivated in commercial plots in Chañe (Segovia), Spain. Symptoms were observed in two plots surveyed representing three hectares, with an incidence greater than 90%, and also in some plots in other nearby municipalities sown with the same batch of seeds. The lesions observed at the ends of the leaves were initially yellow that develop dark brown to black with chlorotic halos on leaflets that turned necrotic. Yellow, Xanthomonas-like colonies were isolated onto YPGA medium (Ridé 1969) from leaf lesions. Two bacterial isolates were selected and confirmed by real-time PCR using a specific primer set for Xanthomonas hortorum pv. carotae (Temple et al. 2013). All isolates were gram-negative, aerobic rods positive for catalase, able of hydrolyzing casein and aesculin and growing at 2% NaCl, while were negative for oxidase and urease tests. Sequences of 16S rRNA gene showed 100% similarity with Xanthomonas campestris, X. arboricola, X. gardneri, X. cynarae strains (GenBank accession numbers: MW077507.1 and MW077508.1 for the isolates CRD19-206.3 and CRD19-206.4, respectively). However, the resulting phylogeny of multilocus sequence analysis (MLSA) of a concatenation of the housekeeping genes atpD, dnaK, and efp (Bui Thi Ngoc et al. 2010), by using neighbour-joining trees generated with 500 bootstrap replicates, grouped the two isolates with the X. hortorum pv. carotae M081 strain (Kimbrel et al. 2011) (GenBank accession numbers: MW161270 and MW161271 for atpD for the two isolates, respectively; MW161268 and MW161269 for dnaK; MW161272 and MW161273 for efp). A pairwise identity analysis revealed a 100% identity between all three isolates. Pathogenicity of the isolates was tested by spray inoculation (Christianson et al. 2015) with a bacterial suspension (108 CFU/ml) prepared in sterile distilled water at 3 to 4 true-leaf stage (six plants per isolate). Sterile distilled water was used as negative control. The inoculated plants were incubated in a growth chamber (25°C and 95% relative humidity [RH]) for 72 h, and then transferred to a greenhouse at 24 to 28°C and 65% RH. Characteristic leaf blight symptoms developed on inoculated carrot plants, while no symptoms were observed on the negative control plants 20 days after inoculation. The bacterium was re-isolated from symptomatic tissue and the identity confirmed through PCR analysis. Based on PCR, morphological and phenotypic tests, sequence analysis, and pathogenicity assays, the isolates were identified as X. hortorum pv. carotae. To our knowledge, this is the first report of bacterial leaf blight of carrot caused by X. hortorum pv. carotae in Spain, and the first molecular and pathological characterization. It is important to early detect this pathogen and take suitable measures to prevent its spread, since it could cause yield losses for a locally important crop such as carrot.
Collapse
Affiliation(s)
- José Luis Palomo Gómez
- Consejería de Agricultura y Ganadería de la Junta de Castilla y León, Centro Regional de Diagnóstico, Salamanca, Spain;
| | - Maria Shima
- Consejería de Agricultura y Ganadería de la Junta de Castilla y León, Centro Regional de Diagnóstico, Salamanca, Spain;
| | - Adela Monterde
- Instituto Valenciano de Investigaciones Agrarias, 70706, Moncada, Valencia, Spain;
| | - Inmaculada Navarro
- Instituto Valenciano de Investigaciones Agrarias, 70706, Moncada, Valencia, Spain;
| | - Silvia Barbé
- Instituto Valenciano de Investigaciones Agrarias, 70706, Moncada, Valenciana, Spain;
| | - Ester Marco-Noales
- Instituto Valenciano de Investigaciones Agrarias, 70706, CV-315 km 10,7, Moncada, Valencia, Spain, 46113;
| |
Collapse
|
8
|
Chai AL, Ben HY, Guo WT, Shi YX, Xie XW, Li L, Li BJ. Quantification of Viable Cells of Pseudomonas syringae pv. tomato in Tomato Seed Using Propidium Monoazide and a Real-Time PCR Assay. PLANT DISEASE 2020; 104:2225-2232. [PMID: 32452750 DOI: 10.1094/pdis-11-19-2397-re] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Pseudomonas syringae pv. tomato is a seedborne pathogen that causes bacterial speck disease in tomato. P. syringae pv. tomato is typically detected in tomato seed using quantitative real-time PCR (qPCR) but the inability of qPCR to distinguish between viable and nonviable cells might lead to an overestimation of viable P. syringae pv. tomato cells. In the present study, a strategy involving a propidium monoazide (PMA) pretreatment followed by a qPCR (PMA-qPCR) assay was developed for quantifying viable P. syringae pv. tomato cells in contaminated tomato seed. PMA could selectively bind to the chromosomal DNA of dead bacterial cells and, therefore, block DNA amplification of qPCR. The primer pair Pst3F/Pst3R was designed based on gene hrpZ to specifically amplify and quantify P. syringae pv. tomato by qPCR. The PMA pretreatment protocol was optimized for selectively detecting viable P. syringae pv. tomato cells, and the optimal PMA concentration and light exposure time were 10 μmol liter-1 and 10 min, respectively. In the sensitivity test, the detection limit of PMA-qPCR for detecting viable cells in bacterial suspension and artificially contaminated tomato seed was 102 CFU ml-1 and 11.86 CFU g-1, respectively. For naturally contaminated tomato seed, viable P. syringae pv. tomato cells were quantified in 6 of the 19 samples, with infestation levels of approximately 102 to 104 CFU g-1. The results indicated that the PMA-qPCR assay is a suitable tool for quantifying viable P. syringae pv. tomato cells in tomato seed, which could be useful for avoiding the potential risks of primary inoculum sources from contaminated seed.
Collapse
Affiliation(s)
- A-Li Chai
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Hai-Yan Ben
- Institute of Plant Protection, Tianjin Academy of Agricultural Sciences, Tianjin 300381, China
| | - Wei-Tao Guo
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Yan-Xia Shi
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Xue-Wen Xie
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Lei Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Bao-Ju Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| |
Collapse
|
9
|
Azospirillum brasilense viable cells enumeration using propidium monoazide-quantitative PCR. Arch Microbiol 2020; 202:1653-1662. [DOI: 10.1007/s00203-020-01877-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 01/23/2020] [Accepted: 04/01/2020] [Indexed: 01/05/2023]
|
10
|
Wang H, Turechek WW. Detection of Viable Xanthomonas fragariae Cells in Strawberry Using Propidium Monoazide and Long-Amplicon Quantitative PCR. PLANT DISEASE 2020; 104:1105-1112. [PMID: 32040389 DOI: 10.1094/pdis-10-19-2248-re] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Xanthomonas fragariae causes angular leaf spot in strawberry. The pathogen's association with its host tissue is thought to be a condition for its survival. Consequently, transmission of the pathogen to field production sites occurs almost exclusively through the movement of contaminated planting stock. The aim of this study was to develop a propidium monoazide (PMA)-quantitative PCR (qPCR) protocol for specific detection of viable X. fragariae cells. The qPCR procedure was developed for two different primer pairs: one producing a long amplicon (863 bp) and the other a short amplicon (61 bp). Both pairs were tested on mixtures of viable and heat-killed bacteria cells, bacteria-spiked strawberry petiole samples, and petioles collected from symptomatic, inoculated plants. The results showed that long-amplicon PMA-qPCR enabled specific and sensitive detection of X. fragariae with a detection limit of 103 CFU/ml, and it significantly improved PMA efficiency in differentiating viable from dead bacterial cells relative to short-amplicon PMA-qPCR. Based on the delta threshold cycle (Ct) values (i.e., the difference in Ct values between PMA-treated and nontreated samples), the long-amplicon PMA-qPCR was able to suppress the detection of dead X. fragariae cells 1.9- to 3.1-fold across all petiole samples tested. The quantification results from PMA-qPCR for mixtures of viable and dead cells were highly correlated with the predicted bacterial concentrations in a linear relationship (R2 = 0.981). This assay can be useful for identifying inoculum sources in the strawberry production cycle, which may lead to improved disease management strategies.
Collapse
Affiliation(s)
- Hehe Wang
- Department of Agricultural and Environmental Sciences, Clemson University, Blackville, SC
| | - William W Turechek
- U.S. Horticultural Research Laboratory, U.S. Department of Agriculture-Agricultural Research Service, Fort Pierce, FL
| |
Collapse
|
11
|
de Paiva BAR, Wendland A, Teixeira NC, Ferreira MASV. Rapid Detection of Xanthomonas citri pv. fuscans and Xanthomonas phaseoli pv. phaseoli in Common Bean by Loop-Mediated Isothermal Amplification. PLANT DISEASE 2020; 104:198-203. [PMID: 31738688 DOI: 10.1094/pdis-02-19-0325-re] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
A single loop-mediated isothermal amplification (LAMP) assay was developed for specific detection of both pathogens that cause bacterial blight in common bean, Xanthomonas phaseoli pv. phaseoli (Xpp) and Xanthomonas citri pv. fuscans (Xcf). The objective was to provide a simple, easy-to-use, specific, and sensitive method to investigate the presence of one or both pathogens in plant material and seeds for routine diagnosis. The detection limits for both pathogens were 10 CFU/ml for cell suspensions and 1 fg of DNA, whereas in conventional PCR, the primers detected up to 105 CFU/ml and 1 ng of DNA. Specificity was confirmed by testing DNA from bean leaves, other Xanthomonas species, common fungal and bacterial bean pathogens, and bacteria from the leaf microbiota. The method was tested with bean leaves inoculated with Xpp, and the pathogen could be detected from 4 h up to 15 days postinoculation, even before disease symptoms were visible. When the method was applied to bacterium detection (Xpp or Xcf) in seed lots from infected plants, the bacterium detection rate was 100% (24 of 24). The pathogens were detected in seeds incubated for just 1 h in saline solution (0.85%), reducing the time needed for bacterium detection. The LAMP assay could be useful as a tool in bean bacterial blight management. Rapid and sensitive detection of bacteria in bean seed lots would reduce the risks of planting highly contaminated seeds in environments favorable to blight multiplication.
Collapse
Affiliation(s)
| | - Adriane Wendland
- Embrapa Arroz e Feijão, 75375-000 Santo Antônio de Goiás, Goiás, Brazil
| | | | - Marisa A S V Ferreira
- Department of Plant Pathology, University of Brasilia, 70910-900 Brasilia, Distrito Federal, Brazil
| |
Collapse
|
12
|
Haack SE, Walse SS, Nguyen K, Adaskaveg JE. Management of Xanthomonas fragariae with Pre- and Postharvest Treatments to Overcome Trade Barriers for California Strawberries. PLANT DISEASE 2019; 103:1256-1263. [PMID: 30964420 DOI: 10.1094/pdis-08-18-1395-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Xanthomonas fragariae, the causal agent of angular leaf spot (ALS) of strawberry, is a quarantine pathogen in some export markets, causing trade restrictions and economic loss to the California fresh-market strawberry industry. Preharvest chemical management options are limited to copper, and there are no postharvest treatments available that reduce populations of the pathogen if ALS is detected at an export destination. Here, we report high preharvest efficacy for the experimental bactericide amino thiadiazole and the commercial product zinc thiadiazole, alone and in mixtures with low rates of copper or the antibiotic kasugamycin, with average disease incidence reduction of up to 92.8% compared with the control. Although effective against quarantine insect pests of strawberry, postharvest methyl bromide fumigation was ineffective against X. fragariae in diseased plant tissue at a standard commercial rate. Postharvest propylene oxide fumigation, used for decades by the California nut industries for insect and microbial disinfestation, significantly reduced X. fragariae populations in infected leaflet tissues by at least 2.5-log compared with controls at a dose of ≥142 µg/ml for 2 h at 15 to 20°C. Fumigated leaflets showed little to no phytotoxicity at effective rates, and fumigated fruit were not significantly affected in appearance or susceptibility to postharvest gray mold or Rhizopus rot following storage at 2°C for 3 days and at 15°C for an additional 5 days. Together, these new treatments offer potential strategies for establishing a systems approach with preharvest treatments significantly reducing the risk of ALS on plants and, in response to quarantine detections, a postharvest fumigation treatment that reduces viable pathogen populations in existing lesions.
Collapse
Affiliation(s)
- Stacey E Haack
- 1 Department of Microbiology and Plant Pathology, University of California, Riverside, CA 92521; and
| | - Spencer S Walse
- 2 San Joaquin Valley Agricultural Sciences Center, United States Department of Agriculture, Agricultural Research Service, Parlier, CA 93648
| | - Kevin Nguyen
- 1 Department of Microbiology and Plant Pathology, University of California, Riverside, CA 92521; and
| | - James E Adaskaveg
- 1 Department of Microbiology and Plant Pathology, University of California, Riverside, CA 92521; and
| |
Collapse
|
13
|
Han S, Jiang N, Lv Q, Kan Y, Hao J, Li J, Luo L. Detection of Clavibacter michiganensis subsp. michiganensis in viable but nonculturable state from tomato seed using improved qPCR. PLoS One 2018; 13:e0196525. [PMID: 29723290 PMCID: PMC5933903 DOI: 10.1371/journal.pone.0196525] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 04/13/2018] [Indexed: 12/02/2022] Open
Abstract
Clavibacter michiganensis subsp. michiganensis (Cmm) is a seed-borne pathogen that causes bacterial canker disease of tomato. Cmm is typically detected in tomato seeds using quantitative real-time polymerase chain reaction (qPCR) combined with culture-based isolation. The viable but nonculturable (VBNC) state of Cmm may result in the underestimation or false negative detection of the pathogen. In the present study, propidium monoazide (PMA) and its improved structure PMAxx were used to pretreat Cmm prior to DNA extraction, followed by qPCR. Both PMA and PMAxx could bind to the chromosomal DNA of dead bacterial cells and therefore block DNA amplification by PCR. This effect, however, does not occur in living bacterial cells, as the chemicals cannot penetrate through the undamaged cell membrane. Both viable and dead Cmm cells were treated with PMA and PMAxx at various concentrations. With this treatment, the range of the cell population was determined for effective detection. PMAxx showed a better discrimination effect than PMA on the viable and dead cells of Cmm and was therefore used throughout the present study. VBNC cells of Cmm (108 CFU mL-1) was induced by 50 μM copper sulfate, which was detected at different sampling times up to a month by using both PMAxx-qPCR and flow cytometry assays. The optimal PMAxx concentration was 20 μM for detecting membrane-intact Cmm cells. High specificity and sensitivity were obtained at Cmm concentrations ranging from 103 to 107 CFU mL-1. The accurate and robust results of PMAxx-qPCR were confirmed by flow cytometry method to detect viable Cmm cells. Furthermore, the PMAxx-qPCR assay was successfully used in detecting VBNC Cmm cells in tomato seeds with as few as 10 seeds per set.
Collapse
Affiliation(s)
- Sining Han
- Department of Plant Pathology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, P. R. China
- Beijing Key Laboratory of Seed Disease Testing and Control (BKL-SDTC), China Agricultural University, Beijing, P. R. China
| | - Na Jiang
- Department of Plant Pathology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, P. R. China
- Beijing Key Laboratory of Seed Disease Testing and Control (BKL-SDTC), China Agricultural University, Beijing, P. R. China
| | - Qingyang Lv
- Department of Plant Pathology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, P. R. China
- Beijing Key Laboratory of Seed Disease Testing and Control (BKL-SDTC), China Agricultural University, Beijing, P. R. China
| | - Yumin Kan
- Department of Plant Pathology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, P. R. China
- Beijing Key Laboratory of Seed Disease Testing and Control (BKL-SDTC), China Agricultural University, Beijing, P. R. China
| | - Jianjun Hao
- School of Food and Agriculture, The University of Maine, Orono, Maine, United States of America
| | - Jianqiang Li
- Department of Plant Pathology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, P. R. China
- Beijing Key Laboratory of Seed Disease Testing and Control (BKL-SDTC), China Agricultural University, Beijing, P. R. China
| | - Laixin Luo
- Department of Plant Pathology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, P. R. China
- Beijing Key Laboratory of Seed Disease Testing and Control (BKL-SDTC), China Agricultural University, Beijing, P. R. China
| |
Collapse
|
14
|
Wang H, Turechek WW. A Loop-Mediated Isothermal Amplification Assay and Sample Preparation Procedure for Sensitive Detection of Xanthomonas fragariae in Strawberry. PLoS One 2016; 11:e0147122. [PMID: 26766068 PMCID: PMC4713083 DOI: 10.1371/journal.pone.0147122] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 12/29/2015] [Indexed: 11/18/2022] Open
Abstract
Xanthomonas fragariae is a bacterium that causes angular leaf spot of strawberry. Asymptomatic infection is common and contributes to the difficulties in disease management. The aim of this study was to develop a loop-mediated isothermal amplification (LAMP) assay as an efficient method for detection of asymptomatic infections of X. fragariae. In addition, a new method of sample preparation was developed that allows sampling of a larger amount of plant tissue, hence increasing the detection rate in real-life samples. The sample preparation procedure includes an overnight incubation of strawberry tissues in phosphate-buffered saline (PBS), followed by a quick sample concentration and a boiling step to extract DNA for amplification. The detection limit of the LAMP assay was approximately 2×10(3) CFU/mL for pure bacteria culture and 300 CFU/mL for bacteria spiked strawberry leaf and petiole samples. LAMP provided a 2-3 fold lower detection limit than the standard qPCR assay but was faster, and more user-friendly. The LAMP assay should serve as a rapid, sensitive and cost-effective tool for detecting asymptomatic infections of X. fragariae in strawberry nursery stock and contribute to improved disease management.
Collapse
Affiliation(s)
- Hehe Wang
- U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS), U.S. Horticultural Research Laboratory, Fort Pierce, FL, United States of America
| | - William W. Turechek
- U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS), U.S. Horticultural Research Laboratory, Fort Pierce, FL, United States of America
- * E-mail:
| |
Collapse
|
15
|
Elkins RB, Temple TN, Shaffer CA, Ingels CA, Lindow SB, Zoller BG, Johnson KB. Evaluation of Dormant-Stage Inoculum Sanitation as a Component of a Fire Blight Management Program for Fresh-Market Bartlett Pear. PLANT DISEASE 2015; 99:1147-1152. [PMID: 30695942 DOI: 10.1094/pdis-10-14-1082-re] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
From 2010 to 2013, the efficacy of copper-based inoculum sanitation as a component of fire blight management programs was evaluated in commercial pear orchards located in northern California. Forty-one 4-ha sections of orchard were split into two equal-sized plots, with the orchardist applying horticultural oil alone to one plot and horticultural oil plus a fixed copper bactericide to the other plot. These treatments were timed to begin just prior to and finish at the "green tip" phenological stage, which occurs about 5 weeks before full bloom. During bloom, flower samples were collected from the plots and subjected to a loop-mediated isothermal DNA amplification (LAMP) assay for specific detection of Erwinia amylovora. Overall, epiphytic populations of E. amylovora on flowers were detected rarely at midbloom (6% of samples) but commonly at petal fall (44% of samples). In three of four seasons, E. amylovora detection in flower samples at a given bloom stage was significantly suppressed in copper-plus-oil-treated plots compared with oil-only plots. All orchards also received antibiotic treatments during the bloom period and, perhaps as a consequence, the development of fire blight was sporadic and not affected significantly by the copper treatment in any season. The pathogen detection data indicate that copper sanitation may add value to a fire blight management program by delaying the increase of epiphytic populations of E. amylovora in flowers to the late stages of the bloom period, at which time the number of susceptible flowers declines rapidly.
Collapse
Affiliation(s)
- Rachel B Elkins
- Lake County Cooperative Extension, University of California, Lakeport 95453-5405
| | - Todd N Temple
- Department of Botany and Plant Pathology, Oregon State University, Corvallis 97331-2902
| | - Carolyn A Shaffer
- Lake County Cooperative Extension, University of California, Lakeport
| | - Chuck A Ingels
- Sacramento County Cooperative Extension, University of California, Sacramento 95827-3823
| | - Steven B Lindow
- Department of Plant and Microbial Biology, University of California, Berkeley 94720-3102
| | | | | |
Collapse
|
16
|
Pothakos V, Taminiau B, Huys G, Nezer C, Daube G, Devlieghere F. Psychrotrophic lactic acid bacteria associated with production batch recalls and sporadic cases of early spoilage in Belgium between 2010 and 2014. Int J Food Microbiol 2014; 191:157-63. [PMID: 25268325 DOI: 10.1016/j.ijfoodmicro.2014.09.013] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Revised: 09/10/2014] [Accepted: 09/14/2014] [Indexed: 12/11/2022]
Abstract
Between 2010 and 2014 several spoilage cases in Belgium occurring in retail foodstuffs prior to the end of shelf-life have been reported to our laboratory. Overall, seven cases involved strictly psychrotrophic lactic acid bacteria (LAB) contamination in packaged and chilled-stored food products. The products derived either from recalls of entire production batches or as specimens of sporadic spoilage manifestations. Some of these samples were returned to the manufacturing companies by consumers who observed the alterations after purchasing the products. The products covered a wide range of foodstuffs (i.e. meat, dairy, vegetable, egg products and composite food) and denoted different spoilage defects. However, the microbiota determined by means of 16S rRNA gene high-throughput sequencing analysis underpin few LAB genera (i.e. Leuconostoc, Lactobacillus, Weissella and Lactococcus), which are frequently encountered nowadays as specific spoilage organisms (SSO) albeit overlooked by mesophilic enumeration methods due to their strictly psychrotrophic character. The present study confirms the spreading of psychrotrophic LAB in Belgian food processing environments leading to unexpected spoilage, corroborating their spoilage dynamics and prevalence in all kinds of packaged and refrigerated foodstuffs in Northern Europe.
Collapse
Affiliation(s)
- Vasileios Pothakos
- LFMFP, Laboratory of Food Microbiology and Food Preservation, Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University, Member of Food2Know, Coupure Links 653, B-9000 Gent, Belgium.
| | - Bernard Taminiau
- Laboratory of Food Microbiology, Department of Food Sciences, Faculty of Veterinary Medicine, University of Liege, Bat. B43b, Sart Tilman, B-4000 Liege, Belgium
| | - Geert Huys
- Laboratory of Microbiology and BCCM/LMG Bacteria Collection, Faculty of Sciences, Ghent University, Member of Food2Know, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium
| | - Carine Nezer
- Quality Partner s.a., rue Hayeneux, 62, 4040 Herstal, Belgium
| | - Georges Daube
- Laboratory of Food Microbiology, Department of Food Sciences, Faculty of Veterinary Medicine, University of Liege, Bat. B43b, Sart Tilman, B-4000 Liege, Belgium
| | - Frank Devlieghere
- LFMFP, Laboratory of Food Microbiology and Food Preservation, Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University, Member of Food2Know, Coupure Links 653, B-9000 Gent, Belgium
| |
Collapse
|