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Uddin MJ, Huang X, Lu X, Li S. Increased Conidia Production and Germination In Vitro Correlate with Virulence Enhancement in Fusarium oxysporum f. sp. cucumerinum. J Fungi (Basel) 2023; 9:847. [PMID: 37623618 PMCID: PMC10455488 DOI: 10.3390/jof9080847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 08/10/2023] [Accepted: 08/12/2023] [Indexed: 08/26/2023] Open
Abstract
Cucumber plants commonly suffer from Fusarium wilt disease, which is caused by Fusarium oxysporum f. sp. cucumerinum (Foc). Although resistant cultivars assist with Fusarium wilt disease control, enhancement of the virulence of Foc has been identified after monoculture of wilt-resistant cultivars. To investigate the biological characteristics that contribute to the virulence evolution of Foc, a wildtype strain foc-3b (WT) and its virulence-enhanced variant Ra-4 (InVir) were compared in terms of their growth, reproduction, stress tolerance, and colonization in cucumber plants. The InVir strain showed similar culture characteristics on PDA media to the WT strain but produced significantly more conidia (>two fold), with a distinctly higher germination rate (>four fold) than the WT strain. The colony diameter of the InVir strain increased faster than the WT strain on PDA plates; however, the mycelia dry weight of the InVir was significantly lower (<70%) than that of the WT harvested from PDB. The InVir strain exhibited a significant increase in tolerance to osmolality (1 M NaCl, 1 M KCl, etc.). The GFP-labeled InVir strain propagated in the cucumber vascular faster than the WT strain. These results suggest that increased conidia production and germination in vitro may correlate with virulence enhancement in Fusarium oxysporum f. sp. cucumerinum. This study will provide an insight into its virulence evolution and help us understand the mechanisms underlying the evolutionary biology of F. oxysporum.
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Affiliation(s)
- Md. Jamal Uddin
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (M.J.U.); (X.H.)
- Crops Division, Bangladesh Agricultural Research Council (BARC), Dhaka 1215, Bangladesh
| | - Xiaoqing Huang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (M.J.U.); (X.H.)
| | - Xiaohong Lu
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (M.J.U.); (X.H.)
| | - Shidong Li
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (M.J.U.); (X.H.)
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Wang L, Guo D, Zhao G, Wang J, Zhang S, Wang C, Guo X. Group IIc WRKY transcription factors regulate cotton resistance to Fusarium oxysporum by promoting GhMKK2-mediated flavonoid biosynthesis. THE NEW PHYTOLOGIST 2022; 236:249-265. [PMID: 35727190 DOI: 10.1111/nph.18329] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 06/09/2022] [Indexed: 05/20/2023]
Abstract
WRKY transcription factors (TFs) are crucial regulators in response to pathogen infection. However, the regulatory mechanisms of WRKY TFs in response to Fusarium oxysporum f. sp. vasinfectum (Fov), the most devastating pathogen of cotton, remain unclear. Here, transcriptome sequencing indicated that the group IIc WRKY TF subfamily was the most important TF subfamily in response to Fov. Gain-of-function and loss-of-function analyses showed that group IIc WRKY TFs positively regulated cotton resistance to Fov. A series of chromatin immunoprecipitation sequencing, yeast one-hybrid assay and electrophoresis mobility shift assay experiments indicated that group IIc WRKY TFs directly bound to the promoter of GhMKK2 and regulated its expression. Importantly, a novel mitogen-activated protein kinase (MAPK) cascade composed of GhMKK2, GhNTF6 and GhMYC2 was identified. The functional analysis indicated that group IIc WRKY TFs induced the GhMKK2-GhNTF6 pathway to increase resistance to Fov by upregulating the GhMYC2-mediated expression of several flavonoid biosynthesis-related genes, which led to flavonoid accumulation. In conclusion, our study demonstrated a novel disease defense mechanism by which the WRKY-MAPK pathway promotes flavonoid biosynthesis to defend against pathogen infection. This pathway improves our understanding of the interaction mode between WRKY TFs and MAPK cascades in plant immunity and the vital role of plant flavonoids in pathogen defense.
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Affiliation(s)
- Lijun Wang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, China
| | - Dezheng Guo
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, China
| | - Guangdong Zhao
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, China
| | - Jiayu Wang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, China
| | - Shuxin Zhang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, China
| | - Chen Wang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, China
| | - Xingqi Guo
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, China
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Sakr N. Adaptation of Phytopathogenic Fungi to Quantitative Host Resistance: In Vitro Selection for Greater Aggressiveness in Fusarium Head Blight Species on Wheat. CYTOL GENET+ 2022. [DOI: 10.3103/s0095452722030112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Sporulation on blood serum increases the virulence of Mucor circinelloides. Microb Pathog 2019; 137:103737. [DOI: 10.1016/j.micpath.2019.103737] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 08/06/2019] [Accepted: 09/08/2019] [Indexed: 11/17/2022]
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Cowger C, Brown JKM. Durability of Quantitative Resistance in Crops: Greater Than We Know? ANNUAL REVIEW OF PHYTOPATHOLOGY 2019; 57:253-277. [PMID: 31206351 DOI: 10.1146/annurev-phyto-082718-100016] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Quantitative resistance (QR) to crop diseases has usually been much more durable than major-gene, effector-triggered resistance. It has been observed that the effectiveness of some QR has eroded as pathogens adapt to it, especially when deployment is extensive and epidemics occur regularly, but it generally declines more slowly than effector-triggered resistance. Changes in aggressiveness and specificity of diverse pathogens on cultivars with QR have been recorded, along with experimental data on fitness costs of pathogen adaptation to QR, but there is little information about molecular mechanisms of adaptation. Some QR has correlated or antagonistic effects on multiple diseases. Longitudinal data on cultivars' disease ratings in trials over several years can be used to assess the significance of QR for durable resistance in crops. It is argued that published data likely underreport the durability of QR, owing to publication bias. The implications of research on QR for plant breeding are discussed.
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Affiliation(s)
- Christina Cowger
- USDA-ARS and North Carolina State University, Raleigh, North Carolina 27695, USA;
| | - James K M Brown
- Department of Crop Genetics, John Innes Centre, Colney, Norwich NR4 7UK, United Kingdom;
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Huang X, Sun M, Lu X, Li S. Serial passage through resistant and susceptible cucumber cultivars affects the virulence of Fusarium oxysporum f. sp. cucumerinum. Microbiologyopen 2019; 8:e00641. [PMID: 29797483 PMCID: PMC6391263 DOI: 10.1002/mbo3.641] [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: 01/10/2018] [Revised: 03/07/2018] [Accepted: 03/24/2018] [Indexed: 12/18/2022] Open
Abstract
Fusarium oxysporum f. sp. cucumerinum (Foc) is the causal pathogen of cucumber Fusarium wilt resulting in losses to cucumber production. To investigate the effects of the selective pressures of host plants on the virulence of Foc, a low virulence isolate, foc-3b, was successively inoculated on resistant and susceptible cucumber cultivars for five generations. The virulence of the original isolate diverged; virulence was significantly strengthened after serial passage on the resistant cultivar and weakened on the susceptible plants (p ˂ .05). The expression of four virulence-related genes of F. oxysporum, G-protein α subunit gene fga1, sucrose nonfermenting 1 gene snf1, F-box protein gene frp1, and Class V chitin synthase gene chsV, was quantified using real-time PCR. All genes were significantly upregulated after serial passage on the resistant cultivar, compared to the original strain, and the expression of snf1 was downregulated in strains re-isolated from the susceptible plants (p ˂ .05). A significant positive correlation was found between the expression levels of gene snf1, frp1, and chsV and disease severity of cucumber Fusarium wilt, suggesting these genes may impact virulence differentiation. This study will improve the management of cucumber Fusarium wilt and provide insight into the mechanisms underlying virulence of F. oxysporum.
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Affiliation(s)
- Xiaoqing Huang
- Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina
| | - Manhong Sun
- Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina
| | - Xiaohong Lu
- Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina
| | - Shidong Li
- Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina
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Burdon JJ, Zhan J, Barrett LG, Papaïx J, Thrall PH. Addressing the Challenges of Pathogen Evolution on the World's Arable Crops. PHYTOPATHOLOGY 2016; 106:1117-1127. [PMID: 27584868 DOI: 10.1094/phyto-01-16-0036-fi] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Advances in genomic and molecular technologies coupled with an increasing understanding of the fine structure of many resistance and infectivity genes, have opened up a new era of hope in controlling the many plant pathogens that continue to be a major source of loss in arable crops. Some new approaches are under consideration including the use of nonhost resistance and the targeting of critical developmental constraints. However, the major thrust of these genomic and molecular approaches is to enhance the identification of resistance genes, to increase their ease of manipulation through marker and gene editing technologies and to lock a range of resistance genes together in simply manipulable resistance gene cassettes. All these approaches essentially continue a strategy that assumes the ability to construct genetic-based resistance barriers that are insurmountable to target pathogens. Here we show how the recent advances in knowledge and marker technologies can be used to generate more durable disease resistance strategies that are based on broad evolutionary principles aimed at presenting pathogens with a shifting, landscape of fluctuating directional selection.
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Affiliation(s)
- Jeremy J Burdon
- First and second authors: Fujian Key Lab of Plant Virology, Institute of Plant Virology; Fujian Agriculture and Forestry University, Fuzhou, China; first, third, and fifth authors: CSIRO Agriculture, PO Box 1600, Canberra, A.C.T. 2601, Australia; and fourth author: INRA Biostatistics and Spatial Processes, Domaine Saint-Paul AgroParc, 84914 Avignon, France
| | - Jiasui Zhan
- First and second authors: Fujian Key Lab of Plant Virology, Institute of Plant Virology; Fujian Agriculture and Forestry University, Fuzhou, China; first, third, and fifth authors: CSIRO Agriculture, PO Box 1600, Canberra, A.C.T. 2601, Australia; and fourth author: INRA Biostatistics and Spatial Processes, Domaine Saint-Paul AgroParc, 84914 Avignon, France
| | - Luke G Barrett
- First and second authors: Fujian Key Lab of Plant Virology, Institute of Plant Virology; Fujian Agriculture and Forestry University, Fuzhou, China; first, third, and fifth authors: CSIRO Agriculture, PO Box 1600, Canberra, A.C.T. 2601, Australia; and fourth author: INRA Biostatistics and Spatial Processes, Domaine Saint-Paul AgroParc, 84914 Avignon, France
| | - Julien Papaïx
- First and second authors: Fujian Key Lab of Plant Virology, Institute of Plant Virology; Fujian Agriculture and Forestry University, Fuzhou, China; first, third, and fifth authors: CSIRO Agriculture, PO Box 1600, Canberra, A.C.T. 2601, Australia; and fourth author: INRA Biostatistics and Spatial Processes, Domaine Saint-Paul AgroParc, 84914 Avignon, France
| | - Peter H Thrall
- First and second authors: Fujian Key Lab of Plant Virology, Institute of Plant Virology; Fujian Agriculture and Forestry University, Fuzhou, China; first, third, and fifth authors: CSIRO Agriculture, PO Box 1600, Canberra, A.C.T. 2601, Australia; and fourth author: INRA Biostatistics and Spatial Processes, Domaine Saint-Paul AgroParc, 84914 Avignon, France
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Voyles J, Johnson LR, Briggs CJ, Cashins SD, Alford RA, Berger L, Skerratt LF, Speare R, Rosenblum EB. Experimental evolution alters the rate and temporal pattern of population growth in Batrachochytrium dendrobatidis, a lethal fungal pathogen of amphibians. Ecol Evol 2014; 4:3633-41. [PMID: 25478154 PMCID: PMC4224537 DOI: 10.1002/ece3.1199] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 07/21/2014] [Accepted: 07/25/2014] [Indexed: 11/13/2022] Open
Abstract
Virulence of infectious pathogens can be unstable and evolve rapidly depending on the evolutionary dynamics of the organism. Experimental evolution can be used to characterize pathogen evolution, often with the underlying objective of understanding evolution of virulence. We used experimental evolution techniques (serial transfer experiments) to investigate differential growth and virulence of Batrachochytrium dendrobatidis (Bd), a fungal pathogen that causes amphibian chytridiomycosis. We tested two lineages of Bd that were derived from a single cryo-archived isolate; one lineage (P10) was passaged 10 times, whereas the second lineage (P50) was passaged 50 times. We quantified time to zoospore release, maximum zoospore densities, and timing of zoospore activity and then modeled population growth rates. We also conducted exposure experiments with a susceptible amphibian species, the common green tree frog (Litoria caerulea) to test the differential pathogenicity. We found that the P50 lineage had shorter time to zoospore production (Tmin), faster rate of sporangia death (ds), and an overall greater intrinsic population growth rate (λ). These patterns of population growth in vitro corresponded with higher prevalence and intensities of infection in exposed Litoria caerulea, although the differences were not significant. Our results corroborate studies that suggest that Bd may be able to evolve relatively rapidly. Our findings also challenge the general assumption that pathogens will always attenuate in culture because shifts in Bd virulence may depend on laboratory culturing practices. These findings have practical implications for the laboratory maintenance of Bd isolates and underscore the importance of understanding the evolution of virulence in amphibian chytridiomycosis.
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Affiliation(s)
- Jamie Voyles
- Department of Biology, New Mexico Tech Socorro, New Mexico, 87801
| | - Leah R Johnson
- Department of Integrative Biology, University of South Florida Tampa, Florida, 33620 ; Department of Ecology, Evolution and Marine Biology, University of California Santa Barbara, California, 93106
| | - Cheryl J Briggs
- Department of Ecology, Evolution and Marine Biology, University of California Santa Barbara, California, 93106
| | - Scott D Cashins
- School of Public Health, Tropical Medicine and Rehabilitation Sciences, Amphibian Disease Ecology Group, James Cook University Townsville, Queensland, 4811, Australia
| | - Ross A Alford
- School of Marine and Tropical Biology, Amphibian Disease Ecology Group, James Cook University Townsville, Queensland, 4811, Australia
| | - Lee Berger
- School of Public Health, Tropical Medicine and Rehabilitation Sciences, Amphibian Disease Ecology Group, James Cook University Townsville, Queensland, 4811, Australia
| | - Lee F Skerratt
- School of Public Health, Tropical Medicine and Rehabilitation Sciences, Amphibian Disease Ecology Group, James Cook University Townsville, Queensland, 4811, Australia
| | - Rick Speare
- School of Public Health, Tropical Medicine and Rehabilitation Sciences, Amphibian Disease Ecology Group, James Cook University Townsville, Queensland, 4811, Australia
| | - Erica Bree Rosenblum
- Department of Environmental Science, Policy and Management, University of California- Berkeley Berkeley, California, 94720-3144
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Frenkel O, Brewer MT, Milgroom MG. Variation in pathogenicity and aggressiveness of Erysiphe necator from different Vitis spp. and geographic origins in the eastern United States. PHYTOPATHOLOGY 2010; 100:1185-1193. [PMID: 20932167 DOI: 10.1094/phyto-01-10-0023] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Eastern North America is considered the center of diversity for many Vitis spp. and for the grape powdery mildew pathogen, Erysiphe necator. However, little is known about populations of E. necator from wild Vitis spp. We determined the phenotypic variation in pathogenicity and aggressiveness of E. necator among isolates from wild and domesticated Vitis spp. from diverse geographic regions in the eastern United States. To test pathogenicity, we inoculated 38 E. necator isolates on three wild Vitis spp., two commercially grown hybrids and the European wine grape, Vitis vinifera. V. rotundifolia (muscadine grape) was the only host species on which complete host specialization was evident; it was only susceptible to isolates collected from V. rotundifolia. All isolates, regardless of source host, were pathogenic on the other Vitis spp. We found no differences in components of aggressiveness latent period and lesion size among isolates from different source hosts when inoculated on V. vinifera, which is highly susceptible to powdery mildew. However significant variation was evident among isolates on the more resistant V. labruscana 'Niagara'. Isolates from the wild species V. aestivalis were the most aggressive, whereas isolates from V. vinifera were not more aggressive than isolates from other source hosts. Greater aggressiveness was also detected among isolates from the southeastern United States compared with isolates from the northeastern United States.
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Affiliation(s)
- Omer Frenkel
- Department of Plant Pathology, Cornell University, Ithaca, NY, USA
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Wang B, Brubaker CL, Summerell BA, Thrall PH, Burdon JJ. Local origin of two vegetative compatibility groups of Fusarium oxysporum f. sp. vasinfectum in Australia. Evol Appl 2010; 3:505-24. [PMID: 25567943 PMCID: PMC3352512 DOI: 10.1111/j.1752-4571.2010.00139.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Accepted: 05/18/2010] [Indexed: 11/30/2022] Open
Abstract
Pathogenicity and genetic diversity of Fusarium oxysporum from geographically widespread native Gossypium populations, including a cotton growing area believed to be the center of origin of VCG 01111 and VCG 01112 of F. oxysporum f. sp. vasinfectum (Fov) in Australia, was determined using glasshouse bioassays and AFLPs. Five lineages (A-E) were identified among 856 isolates. Of these, 12% were strongly pathogenic on cotton, 10% were weakly pathogenic and designated wild Fov, while 78% were nonpathogenic. In contrast to the occurrence of pathogenic isolates in all five lineages in soils associated with wild Gossypium, in cotton growing areas only three lineages (A, B, E) occurred and all pathogenic isolates belonged to two subgroups in lineage A. One of these contained VCG 01111 isolates while the other contained VCG 01112 isolates. Sequence analyses of translation elongation factor-1α, mitochondrial small subunit rDNA, nitrate reductase and phosphate permease confirmed that Australian Fov isolates were more closely related to lineage A isolates of native F. oxysporum than to Fov races 1-8 found overseas. These results strongly support a local evolutionary origin for Fov in Australian cotton growing regions.
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Affiliation(s)
- Bo Wang
- CSIRO Plant IndustryCanberra, ACT, Australia
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Walsh JL, Laurence MH, Liew ECY, Sangalang AE, Burgess LW, Summerell BA, Petrovic T. Fusarium: two endophytic novel species from tropical grasses of northern Australia. FUNGAL DIVERS 2010. [DOI: 10.1007/s13225-010-0035-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Holmes EA, Bennett RS, Spurgeon DW, Colyer PD, Davis RM. New Genotypes of Fusarium oxysporum f. sp. vasinfectum from the Southeastern United States. PLANT DISEASE 2009; 93:1298-1304. [PMID: 30759505 DOI: 10.1094/pdis-93-12-1298] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Sixty-one isolates of Fusarium oxysporum f. sp. vasinfectum were collected from cotton plants (Gossypium spp.) with symptoms of Fusarium wilt to determine the composition of races present in the southeastern United States. Analysis of partial sequences of the translation elongation factor gene revealed four novel genotypes, as well as the presence of races 3 and 8 for the first time in the United States outside of California. The majority of isolates (16 of 27) sampled from Arkansas were novel genotypes. A subset of isolates representing the novel genotypes was compared with previously described races using sequences from translation elongation factor, phosphate permase, and β-tubulin genes and their pathogenicity on a total of six Upland (Gossypium hirsutum) and Pima (G. barbadense) cotton cultivars. Two of the novel genotypes belonged to a clade containing races 1, 2, 4, 6, and 8 and two shared ancestry with race 3. All new genotypes were pathogenic to at least some of the cotton cultivars tested. The Pima cv. Phytogen 800 was relatively resistant to all genotypes of the pathogen. These results indicate that the population of F. oxysporum f. sp. vasinfectum in the southeastern United States is more diverse than previously recognized.
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Affiliation(s)
- E A Holmes
- Department of Plant Pathology, University of California, Davis 95616
| | - R S Bennett
- Western Integrated Cropping Systems Research Unit, United States Department of Agriculture-Agricultural Research Service, Shafter, CA 93263
| | - D W Spurgeon
- Western Integrated Cropping Systems Research Unit, United States Department of Agriculture-Agricultural Research Service, Shafter, CA 93263
| | - P D Colyer
- Louisiana Agricultural Experiment Station, Red River Research Station, Bossier City 71113-8550
| | - R M Davis
- Department of Plant Pathology, University of California, Davis
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