1
|
Hamilton R, Jacobs JL, McCoy AG, Kelly HM, Bradley CA, Malvick DK, Rojas JA, Chilvers MI. Multistate Sensitivity Monitoring of Fusarium virguliforme to the SDHI Fungicides Fluopyram and Pydiflumetofen in the United States. PLANT DISEASE 2024; 108:1602-1611. [PMID: 38127633 DOI: 10.1094/pdis-11-23-2465-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: 12/23/2023]
Abstract
Sudden death syndrome (SDS), caused by Fusarium virguliforme, is an important yield-limiting disease of soybean (Glycine max). From 1996 to 2022, cumulative yield losses attributed to SDS in North America totaled over 25 million metric tons, which was valued at over US $7.8 billion. Seed treatments are widely used to manage SDS by reducing early season soybean root infection by F. virguliforme. Fluopyram (succinate dehydrogenase inhibitor [SDHI] - FRAC 7), a fungicide seed treatment for SDS management, has been registered for use on soybean in the United States since 2014. A baseline sensitivity study conducted in 2014 evaluated 130 F. virguliforme isolates collected from five states to fluopyram in a mycelial growth inhibition assay and reported a mean EC50 of 3.35 mg/liter. This baseline study provided the foundation for the objectives of this research: to detect any statistically significant change in fluopyram sensitivity over time and geographical regions within the United States and to investigate sensitivity to the fungicide pydiflumetofen. We repeated fluopyram sensitivity testing on a panel of 80 historical F. virguliforme isolates collected from 2006 to 2013 (76 of which were used in the baseline study) and conducted testing on 123 contemporary isolates collected from 2016 to 2022 from 11 states. This study estimated a mean absolute EC50 of 3.95 mg/liter in isolates collected from 2006 to 2013 and a mean absolute EC50 of 4.19 mg/liter in those collected in 2016 to 2022. There was no significant change in fluopyram sensitivity (P = 0.1) identified between the historical and contemporary isolates. A subset of 23 isolates, tested against pydiflumetofen under the same conditions, estimated an absolute mean EC50 of 0.11 mg/liter. Moderate correlation was detected between fluopyram and pydiflumetofen sensitivity estimates (R = 0.53; P < 0.001). These findings enable future fluopyram and pydiflumetofen resistance monitoring and inform current soybean SDS management strategies in a regional and national context.
Collapse
Affiliation(s)
- Ryan Hamilton
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI 48824
| | - Janette L Jacobs
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI 48824
| | - Austin G McCoy
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI 48824
| | - Heather M Kelly
- Department of Entomology and Plant Pathology, The University of Tennessee Institute of Agriculture, Jackson, TN 38301
| | - Carl A Bradley
- Department of Plant Pathology, University of Kentucky, Princeton, KY 42445
| | - Dean K Malvick
- Department of Plant Pathology, University of Minnesota, St. Paul, MN 55108
| | - J Alejandro Rojas
- Department of Entomology and Plant Pathology, University of Arkansas, Fayetteville, AR 72701
| | - Martin I Chilvers
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI 48824
| |
Collapse
|
2
|
Beesley A, Beyer SF, Wanders V, Levecque S, Bredenbruch S, Habash SS, Schleker ASS, Gätgens J, Oldiges M, Schultheiss H, Conrath U, Langenbach CJG. Engineered coumarin accumulation reduces mycotoxin-induced oxidative stress and disease susceptibility. PLANT BIOTECHNOLOGY JOURNAL 2023; 21:2490-2506. [PMID: 37578146 PMCID: PMC10651151 DOI: 10.1111/pbi.14144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 06/23/2023] [Accepted: 07/23/2023] [Indexed: 08/15/2023]
Abstract
Coumarins can fight pathogens and are thus promising for crop protection. Their biosynthesis, however, has not yet been engineered in crops. We tailored the constitutive accumulation of coumarins in transgenic Nicotiana benthamiana, Glycine max and Arabidopsis thaliana plants, as well as in Nicotiana tabacum BY-2 suspension cells. We did so by overexpressing A. thaliana feruloyl-CoA 6-hydroxylase 1 (AtF6'H1), encoding the key enzyme of scopoletin biosynthesis. Besides scopoletin and its glucoside scopolin, esculin at low level was the only other coumarin detected in transgenic cells. Mechanical damage of scopolin-accumulating tissue led to a swift release of scopoletin, presumably from the scopolin pool. High scopolin levels in A. thaliana roots coincided with reduced susceptibility to the root-parasitic nematode Heterodera schachtii. In addition, transgenic soybean plants were more tolerant to the soil-borne pathogenic fungus Fusarium virguliforme. Because mycotoxin-induced accumulation of reactive oxygen species and cell death were reduced in the AtF6'H1-overexpressors, the weaker sensitivity to F. virguliforme may be caused by attenuated oxidative damage of coumarin-hyperaccumulating cells. Together, engineered coumarin accumulation is promising for enhanced disease resilience of crops.
Collapse
Affiliation(s)
| | - Sebastian F. Beyer
- Department of Plant PhysiologyRWTH Aachen UniversityAachenGermany
- Present address:
BASF SE, Agricultural CenterLimburgerhofGermany
| | - Verena Wanders
- Department of Plant PhysiologyRWTH Aachen UniversityAachenGermany
| | - Sophie Levecque
- Department of Plant PhysiologyRWTH Aachen UniversityAachenGermany
| | | | - Samer S. Habash
- Department of Molecular PhytomedicineUniversity of BonnBonnGermany
- Present address:
BASF Vegetable SeedsNunhemNetherlands
| | | | - Jochem Gätgens
- Department of Bioprocesses and BioanalyticsResearch Center Jülich GmbHJülichGermany
| | - Marco Oldiges
- Department of Bioprocesses and BioanalyticsResearch Center Jülich GmbHJülichGermany
| | | | - Uwe Conrath
- Department of Plant PhysiologyRWTH Aachen UniversityAachenGermany
| | | |
Collapse
|
3
|
da Silva LL, Tian H, Schemerhorn B, Xu JR, Cai G. Genome-Wide Informative Microsatellite Markers and Population Structure of Fusarium virguliforme from Argentina and the USA. J Fungi (Basel) 2023; 9:1109. [PMID: 37998914 PMCID: PMC10672573 DOI: 10.3390/jof9111109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 11/11/2023] [Accepted: 11/12/2023] [Indexed: 11/25/2023] Open
Abstract
Soybean sudden death syndrome (SDS) is a destructive disease that causes substantial yield losses in South and North America. Whereas four Fusarium species were identified as the causal agents, F. virguliforme is the primary SDS-causing pathogen in North America and it also contributes substantially to SDS in Argentina. In this study, we comparatively analyzed genome assemblies of four F. virguliforme strains and identified 29 informative microsatellite markers. Sixteen of the 29 markers were used to investigate the genetic diversity and population structure of this pathogen in a collection of 90 strains from Argentina and the USA. A total of 37 multilocus genotypes (MLGs) were identified, including 10 MLGs in Argentina and 26 in the USA. Only MLG2, the most dominant MLG, was found in both countries. Analyses with three different approaches showed that these MLGs could be grouped into three clusters. Cluster IA consisting of four MLGs exclusively from the USA has much higher genetic diversity than the other two clusters, suggesting that it may be the ancestral cluster although additional data are necessary to support this hypothesis. Clusters IB and II consisted of 13 and 21 MLGs, respectively. MLGs belonging to these two clusters were present in all four sampled states in Argentina and all five sampled states in the USA.
Collapse
Affiliation(s)
- Leandro Lopes da Silva
- Crop Production and Pest Control Research Unit, Agricultural Research Service, United States Department of Agriculture (USDA), West Lafayette, IN 47907, USA
| | - Huan Tian
- Botany and Plant Pathology Department, Purdue University, West Lafayette, IN 47907, USA
| | - Brandi Schemerhorn
- Crop Production and Pest Control Research Unit, Agricultural Research Service, United States Department of Agriculture (USDA), West Lafayette, IN 47907, USA
| | - Jin-Rong Xu
- Botany and Plant Pathology Department, Purdue University, West Lafayette, IN 47907, USA
| | - Guohong Cai
- Crop Production and Pest Control Research Unit, Agricultural Research Service, United States Department of Agriculture (USDA), West Lafayette, IN 47907, USA
- Botany and Plant Pathology Department, Purdue University, West Lafayette, IN 47907, USA
| |
Collapse
|
4
|
Brown MT, Mueller DS, Kandel YR, Telenko DEP. Influence of Integrated Management Strategies on Soybean Sudden Death Syndrome (SDS) Root Infection, Foliar Symptoms, Yield and Net Returns. Pathogens 2023; 12:913. [PMID: 37513760 PMCID: PMC10385733 DOI: 10.3390/pathogens12070913] [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: 05/05/2023] [Revised: 06/26/2023] [Accepted: 07/03/2023] [Indexed: 07/30/2023] Open
Abstract
Three soybean field trials were conducted in Indiana to evaluate the integration of seed treatment, cultivar selection, and seeding rate on sudden death syndrome (SDS) root rot, pathogen load in the root, foliar symptoms, yield, and net return. Two soybean cultivars, one moderately resistant and one susceptible to SDS, were planted at three seeding rates (272,277 seeds/ha, 346,535 seeds/ha, and 420,792 seeds/ha). Fluopyram and pydiflumetofen seed treatments were applied to both cultivars, and the cultivars were then compared with a control. Low foliar SDS disease pressure was observed in our study. Seed treatment with either fluopyram or pydiflumetofen and the use of a moderately resistant cultivar decreased Fusarium virguliforme DNA concentration in the root relative to the control and the use of a susceptible cultivar. Fluopyram significantly reduced visual root rot severity by 8.8% and increased yield by 105 kg/ha relative to the control but was not different from pydiflumetofen. However, pydiflumetofen performed the same as the control with respect to root rot severity and yield. Findings from this study support the use of a seed treatment to protect roots from infection and the use of a moderately resistant cultivar planted at a seeding rate of 346,535 seeds/ha to protect yield and maximize net returns when a field has low foliar SDS pressure.
Collapse
Affiliation(s)
- Mariama T Brown
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA
| | - Daren S Mueller
- Department of Plant Pathology, Entomology, and Microbiology, Iowa State University, Ames, IA 50011, USA
| | - Yuba R Kandel
- 5Metis Inc., Research Triangle Park, Durham, NC 27709, USA
| | - Darcy E P Telenko
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA
| |
Collapse
|
5
|
Kandel YR, Lawson MN, Brown MT, Chilvers MI, Kleczewski NM, Telenko DEP, Tenuta AU, Smith DL, Mueller DS. Field and Greenhouse Assessment of Seed Treatment Fungicides for Management of Sudden Death Syndrome and Yield Response of Soybean. PLANT DISEASE 2023; 107:1131-1138. [PMID: 36190301 DOI: 10.1094/pdis-03-22-0527-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: 06/16/2023]
Abstract
Seed treatments for the management of sudden death syndrome (SDS) caused by Fusarium virguliforme are available in the United States and Canada; however, side-by-side comparisons of these seed treatments are lacking. Sixteen field experiments were established in Illinois, Indiana, Iowa, Michigan, and Wisconsin, United States, and Ontario, Canada, in 2019 and 2020 to evaluate seed treatment combinations. Treatments included a nontreated check (NTC), fungicide and insecticide base seed treatments (base), fluopyram, base + fluopyram, base + saponin extracts from Chenopodium quinoa, base + fluopyram + heat-killed Burkholderia rinojenses, base + pydiflumetofen, base + thiabendazole + heat-killed B. rinojenses, and base + thiabendazole + C. quinoa extracts + heat-killed B. rinojenses. Treatments were tested on SDS moderately resistant and susceptible soybean cultivars at each location. Overall, NTC and base had the most root rot, most foliar disease index (FDX), and lowest yield. Base + fluopyram and base + pydiflumetofen were most effective for managing SDS. Moderately resistant cultivars reduced FDX in both years but visual root rot was greater on the moderately resistant than the susceptible cultivars in 2020. Yield response to cultivar was also inconsistent between the 2 years. In 2020, the susceptible cultivar provided significantly more yield than the moderately resistant cultivar. Treatment effect for root rot and FDX was similar in field and greenhouse evaluations. These results reinforce the need to include root rot evaluations in addition to foliar disease evaluations in the breeding process for resistance to F. virguliforme and highlights the importance of an integrated SDS management plan because not a single management tactic alone provides adequate control of the disease.
Collapse
Affiliation(s)
- Yuba R Kandel
- Department of Plant Pathology, Entomology and Microbiology, Iowa State University, Ames, IA 50011, U.S.A
| | - Maia N Lawson
- Department of Plant Pathology, Entomology and Microbiology, Iowa State University, Ames, IA 50011, U.S.A
| | - Mariama T Brown
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, U.S.A
| | - Martin I Chilvers
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824, U.S.A
| | - Nathan M Kleczewski
- Department of Crop Sciences, University of Illinois, Urbana, IL 61801, U.S.A
| | - Darcy E P Telenko
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, U.S.A
| | - Albert U Tenuta
- Ontario Ministry of Agriculture, Food, and Rural Affairs, Ridgetown, Ontario N0P2C0, Canada
| | - Damon L Smith
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI 53706, U.S.A
| | - Daren S Mueller
- Department of Plant Pathology, Entomology and Microbiology, Iowa State University, Ames, IA 50011, U.S.A
| |
Collapse
|
6
|
Raza MM, Kaiser MS, Eggenberger SK, Nutter FW, Leandro LFS. Time of Soybean Sudden Death Syndrome Foliar Symptom Onset Influences Final Disease Intensity, Yield, and Yield Components. PLANT DISEASE 2022; 106:2392-2402. [PMID: 35196103 DOI: 10.1094/pdis-07-21-1551-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
Sudden death syndrome (SDS), caused by Fusarium virguliforme, causes substantial yield losses in soybean. However, relationships between soybean yield and components of disease progress, including time of disease onset, are poorly understood. Individual soybean plants (2018) and quadrats (2016 to 2018) were monitored in commercial fields and experimental plots in Iowa to quantify the impact of SDS foliar symptom onset on final SDS intensity, soybean yield components, and yield. The date when SDS foliar symptoms were first detected (onset time) and progress of SDS incidence and severity were recorded weekly. Individual soybean plants and quadrats were harvested at the end of each season. Beta-regression showed that date of SDS onset had a consistent and stable effect on final disease intensity both at individual plant and quadrat levels. The slope of the relationship between date of SDS onset and final SDS severity was common across all field sites and years. Weighted linear regression revealed that SDS onset explained 60 to 83% of the variation in number of pods, number of seeds, and total seed weight in individual plants, and 94 to 97% of the variation in seed yield in quadrats. Soybean yield damage functions (slopes) indicated that for each day SDS onset was delayed, soybean yield increased by 30.5 to 31.3 kg/ha. This new quantitative information improves understanding of the impact of SDS on final disease intensity and soybean yield. Further experiments are needed to determine how this relationship is affected by site-specific factors.
Collapse
Affiliation(s)
- Muhammad M Raza
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA 50011
| | - Mark S Kaiser
- Department of Statistics, Iowa State University, Ames, IA 50011
| | - Sharon K Eggenberger
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA 50011
| | - Forest W Nutter
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA 50011
| | - Leonor F S Leandro
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA 50011
| |
Collapse
|
7
|
Rodriguez MC, Sautua F, Scandiani M, Carmona M, Asurmendi S. Current recommendations and novel strategies for sustainable management of soybean sudden death syndrome. PEST MANAGEMENT SCIENCE 2021; 77:4238-4248. [PMID: 33942966 DOI: 10.1002/ps.6458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 04/14/2021] [Accepted: 05/04/2021] [Indexed: 05/12/2023]
Abstract
The increase in food production requires reduction of the damage caused by plant pathogens, minimizing the environmental impact of management practices. Soil-borne pathogens are among the most relevant pathogens that affect soybean crop yield. Soybean sudden death syndrome (SDS), caused by several distinct species of Fusarium, produces significant yield losses in the leading soybean-producing countries in North and South America. Current management strategies for SDS are scarce since there are no highly resistant cultivars and only a few fungicide seed treatments are available. Because of this, innovative approaches for SDS management need to be developed. Here, we summarize recently explored strategies based on plant nutrition, biological control, priming of plant defenses, host-induced gene silencing, and the development of new SDS-resistance cultivars using precision breeding techniques. Finally, sustainable management of SDS should also consider cultural control practices with minimal environmental impact. © 2021 Society of Chemical Industry.
Collapse
Affiliation(s)
- Maria C Rodriguez
- Instituto de Agrobiotecnología y Biología Molecular, CICVyA, Instituto Nacional de Tecnología Agropecuaria, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Francisco Sautua
- Fitopatología, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Mercedes Scandiani
- Centro de Referencia de Micología, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Marcelo Carmona
- Fitopatología, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Sebastián Asurmendi
- Instituto de Agrobiotecnología y Biología Molecular, CICVyA, Instituto Nacional de Tecnología Agropecuaria, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| |
Collapse
|
8
|
Kambakam S, Ngaki MN, Sahu BB, Kandel DR, Singh P, Sumit R, Swaminathan S, Muliyar-Krishna R, Bhattacharyya MK. Arabidopsis non-host resistance PSS30 gene enhances broad-spectrum disease resistance in the soybean cultivar Williams 82. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 107:1432-1446. [PMID: 34171147 DOI: 10.1111/tpj.15392] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 06/03/2021] [Accepted: 06/19/2021] [Indexed: 05/27/2023]
Abstract
Non-host resistance (NHR), which protects all members of a plant species from non-adapted or non-host plant pathogens, is the most common form of plant immunity. NHR provides the most durable and robust form of broad-spectrum immunity against non-adaptive pathogens pathogenic to other crop species. In a mutant screen for loss of Arabidopsis (Arabidopsis thaliana) NHR against the soybean (Glycine max (L.) Merr.) pathogen Phytophthora sojae, the Phytophthora sojae-susceptible 30 (pss30) mutant was identified. The pss30 mutant is also susceptible to the soybean pathogen Fusarium virguliforme. PSS30 encodes a folate transporter, AtFOLT1, which was previously localized to chloroplasts and implicated in the transport of folate from the cytosol to plastids. We show that two Arabidopsis folate biosynthesis mutants with reduced folate levels exhibit a loss of non-host immunity against P. sojae. As compared to the wild-type Col-0 ecotype, the steady-state folate levels are reduced in the pss1, atfolt1 and two folate biosynthesis mutants, suggesting that folate is required for non-host immunity. Overexpression of AtFOLT1 enhances immunity of transgenic soybean lines against two serious soybean pathogens, the fungal pathogen F. virguliforme and the soybean cyst nematode (SCN) Heterodera glycines. Transgenic lines showing enhanced SCN resistance also showed increased levels of folate accumulation. This study thus suggests that folate contributes to non-host plant immunity and that overexpression of a non-host resistance gene could be a suitable strategy for generating broad-spectrum disease resistance in crop plants.
Collapse
Affiliation(s)
- Sekhar Kambakam
- Department of Agronomy, Iowa State University, Ames, 50011, USA
| | | | - Binod B Sahu
- Department of Agronomy, Iowa State University, Ames, 50011, USA
| | - Devi R Kandel
- Department of Agronomy, Iowa State University, Ames, 50011, USA
| | - Prashant Singh
- Department of Agronomy, Iowa State University, Ames, 50011, USA
| | - Rishi Sumit
- Department of Agronomy, Iowa State University, Ames, 50011, USA
| | | | | | | |
Collapse
|
9
|
Ngaki MN, Sahoo DK, Wang B, Bhattacharyya MK. Overexpression of a plasma membrane protein generated broad-spectrum immunity in soybean. PLANT BIOTECHNOLOGY JOURNAL 2021; 19:502-516. [PMID: 32954627 PMCID: PMC7957895 DOI: 10.1111/pbi.13479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 07/17/2020] [Accepted: 08/06/2020] [Indexed: 05/10/2023]
Abstract
Plants fight-off pathogens and pests by manifesting an array of defence responses using their innate immunity mechanisms. Here we report the identification of a novel soybean gene encoding a plasma membrane protein, transcription of which is suppressed following infection with the fungal pathogen, Fusarium virguliforme. Overexpression of the protein led to enhanced resistance against not only against F. virguliforme, but also against spider mites (Tetranychus urticae, Koch), soybean aphids (Aphis glycines, Matsumura) and soybean cyst nematode (Heterodera glycines). We, therefore, name this protein as Glycine max disease resistance 1 (GmDR1; Glyma.10g094800). The homologues of GmDR1 have been detected only in legumes, cocoa, jute and cotton. The deduced GmDR1 protein contains 73 amino acids. GmDR1 is predicted to contain an ecto- and two transmembrane domains. Transient expression of the green fluorescent protein fused GmDR1 protein in soybean leaves showed that it is a plasma membrane protein. We investigated if chitin, a pathogen-associated molecular pattern (PAMP), common to all pathogen and pests considered in this study, can significantly enhance defence pathways among the GmDR1-overexpressed transgenic soybean lines. Chitin induces marker genes of the salicylic- and jasmonic acid-mediated defence pathways, but suppresses the defence pathway regulated by ethylene. Chitin induced SA- and JA-regulated defence pathways may be one of the mechanisms involved in generating broad-spectrum resistance among the GmDR1-overexpressed transgenic soybean lines against two serious pathogens and two pests including spider mites, against which no known resistance genes have been identified in soybean and among the most other crop species.
Collapse
Affiliation(s)
| | | | - Bing Wang
- Department of AgronomyIowa State UniversityAmesIAUSA
- Present address:
Department of EnergyJoint Genome InstituteWalnut CreekCAUSA
| | | |
Collapse
|
10
|
Ku YS, Cheng SS, Gerhardt A, Cheung MY, Contador CA, Poon LYW, Lam HM. Secretory Peptides as Bullets: Effector Peptides from Pathogens against Antimicrobial Peptides from Soybean. Int J Mol Sci 2020; 21:E9294. [PMID: 33291499 PMCID: PMC7730307 DOI: 10.3390/ijms21239294] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 11/24/2020] [Accepted: 12/03/2020] [Indexed: 12/24/2022] Open
Abstract
Soybean is an important crop as both human food and animal feed. However, the yield of soybean is heavily impacted by biotic stresses including insect attack and pathogen infection. Insect bites usually make the plants vulnerable to pathogen infection, which causes diseases. Fungi, oomycetes, bacteria, viruses, and nematodes are major soybean pathogens. The infection by pathogens and the defenses mounted by soybean are an interactive and dynamic process. Using fungi, oomycetes, and bacteria as examples, we will discuss the recognition of pathogens by soybean at the molecular level. In this review, we will discuss both the secretory peptides for soybean plant infection and those for pathogen inhibition. Pathogenic secretory peptides and peptides secreted by soybean and its associated microbes will be included. We will also explore the possible use of externally applied antimicrobial peptides identical to those secreted by soybean and its associated microbes as biopesticides.
Collapse
Affiliation(s)
- Yee-Shan Ku
- Centre for Soybean Research of the State Key Laboratory of Agrobiotechnology and School of Life Sciences, The Chinese University of Hong Kong, Hong Kong; (Y.-S.K.); (S.-S.C.); (A.G.); (M.-Y.C.); (C.A.C.); (L.-Y.W.P.)
| | - Sau-Shan Cheng
- Centre for Soybean Research of the State Key Laboratory of Agrobiotechnology and School of Life Sciences, The Chinese University of Hong Kong, Hong Kong; (Y.-S.K.); (S.-S.C.); (A.G.); (M.-Y.C.); (C.A.C.); (L.-Y.W.P.)
| | - Aisha Gerhardt
- Centre for Soybean Research of the State Key Laboratory of Agrobiotechnology and School of Life Sciences, The Chinese University of Hong Kong, Hong Kong; (Y.-S.K.); (S.-S.C.); (A.G.); (M.-Y.C.); (C.A.C.); (L.-Y.W.P.)
- Centre for Organismal Studies (COS), Heidelberg University, Im Neuenheimer Feld 230, 69120 Heidelberg, Germany
| | - Ming-Yan Cheung
- Centre for Soybean Research of the State Key Laboratory of Agrobiotechnology and School of Life Sciences, The Chinese University of Hong Kong, Hong Kong; (Y.-S.K.); (S.-S.C.); (A.G.); (M.-Y.C.); (C.A.C.); (L.-Y.W.P.)
| | - Carolina A. Contador
- Centre for Soybean Research of the State Key Laboratory of Agrobiotechnology and School of Life Sciences, The Chinese University of Hong Kong, Hong Kong; (Y.-S.K.); (S.-S.C.); (A.G.); (M.-Y.C.); (C.A.C.); (L.-Y.W.P.)
| | - Lok-Yiu Winnie Poon
- Centre for Soybean Research of the State Key Laboratory of Agrobiotechnology and School of Life Sciences, The Chinese University of Hong Kong, Hong Kong; (Y.-S.K.); (S.-S.C.); (A.G.); (M.-Y.C.); (C.A.C.); (L.-Y.W.P.)
| | - Hon-Ming Lam
- Centre for Soybean Research of the State Key Laboratory of Agrobiotechnology and School of Life Sciences, The Chinese University of Hong Kong, Hong Kong; (Y.-S.K.); (S.-S.C.); (A.G.); (M.-Y.C.); (C.A.C.); (L.-Y.W.P.)
| |
Collapse
|
11
|
Madina MH, Rahman MS, Huang X, Zhang Y, Zheng H, Germain H. A Poplar Rust Effector Protein Associates with Protein Disulfide Isomerase and Enhances Plant Susceptibility. BIOLOGY 2020; 9:E294. [PMID: 32947987 PMCID: PMC7564345 DOI: 10.3390/biology9090294] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 09/04/2020] [Accepted: 09/07/2020] [Indexed: 11/17/2022]
Abstract
Melampsora larici-populina (Mlp), the causal agent of Populus leaf rust, secretes an array of effectors into the host through the haustorium to gain nutrients and suppress immunity. The precise mechanisms by which these effectors promote virulence remain unclear. To address this question, we developed a transgenic Arabidopsis line expressing a candidate effector, Mlp124357. Constitutive expression of the effector increased plant susceptibility to pathogens. A GxxxG motif present in Mlp124357 is required for its subcellular localization at the vacuolar membrane of the plant cell, as replacement of the glycine residues with alanines led to the delocalization of Mlp124357 to the nucleus and cytoplasm. We used immunoprecipitation and mass spectrometry (MS) to identify Mlp124357 interaction partners. Only one of the putative interaction partners knock-out line caused delocalization of the effector, indicating that Arabidopsis protein disulfide isomerase-11 (AtPDI-11) is required for the effector localization. This interaction was further confirmed by a complementation test, a yeast-two hybrid assay and a molecular modeling experiment. Moreover, localization results and infection assays suggest that AtPDI-11 act as a helper for Mlp124357. In summary, our findings established that one of Mlp effectors resides at the vacuole surface and modulates plant susceptibility.
Collapse
Affiliation(s)
- Mst Hur Madina
- Department of Chemistry, Biochemistry and Physics, Université du Québec à Trois-Rivières, 3351 boulevard des Forges, Trois-Rivières, QC G9A 5H7, Canada; (M.H.M.); (M.S.R.)
| | - Md Saifur Rahman
- Department of Chemistry, Biochemistry and Physics, Université du Québec à Trois-Rivières, 3351 boulevard des Forges, Trois-Rivières, QC G9A 5H7, Canada; (M.H.M.); (M.S.R.)
| | - Xiaoqiang Huang
- Department of Computational Medicine and Bioinformatics, University of Michigan, 100 Washtenaw Avenue, Ann Arbor, MI 48109, USA; (X.H.); (Y.Z.)
| | - Yang Zhang
- Department of Computational Medicine and Bioinformatics, University of Michigan, 100 Washtenaw Avenue, Ann Arbor, MI 48109, USA; (X.H.); (Y.Z.)
| | - Huanquan Zheng
- Department of Biology, McGill University, 1205 Dr. Penfield Avenue, Montreal, QC H3A 1B1, Canada;
| | - Hugo Germain
- Department of Chemistry, Biochemistry and Physics, Université du Québec à Trois-Rivières, 3351 boulevard des Forges, Trois-Rivières, QC G9A 5H7, Canada; (M.H.M.); (M.S.R.)
| |
Collapse
|
12
|
Kandel YR, Bradley CA, Chilvers MI, Mathew FM, Tenuta AU, Smith DL, Wise KA, Mueller DS. Relationship Between Sudden Death Syndrome caused by Fusarium virguliforme and Soybean Yield: A Meta-Analysis. PLANT DISEASE 2020; 104:1736-1743. [PMID: 32289247 DOI: 10.1094/pdis-11-19-2441-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: 05/12/2023]
Abstract
In total, 52 uniform field experiments were conducted in Illinois, Indiana, Iowa, Michigan, South Dakota, and Wisconsin in the United States and Ontario, Canada from 2013 to 2017 comparing crop protection products against sudden death syndrome (SDS) of soybean. Data were analyzed using meta-analytic models to summarize the relationship between foliar disease index (FDX) and yield. For each study, correlation and regression analyses were performed separately to determine three effect sizes: Fisher's transformation of correlation coefficients (Z r ), intercept (β0), and slope (β1). Random- and mixed-effect meta-analyses were used to summarize the effect sizes. Study- and location-specific moderator variables FDX (low < 10% and high ≥ 10%), date of planting (early = prior to 7 May, conventional = 7 to 21 May, and late = after 21 May) cultivar (susceptible and partially resistant to SDS), study location, and growing season were used as fixed effects. The overall mean effect sizes of transformed correlation coefficient [Formula: see text] r was -0.41 and different from zero (P < 0.001), indicating that yield was negatively correlated with FDX. The [Formula: see text] r was affected by disease level (P < 0.01) and cultivar (P = 0.02), with a greater effect at higher disease levels and with susceptible cultivars. The mean [Formula: see text] 0 was 4,121 kg/ha and mean [Formula: see text] 1 was -21 kg/ha/% FDX and were different from zero (P < 0.01). Results from these data indicate that, for every unit of FDX increase, yield was decreased by 0.5%. Study locations and year affected the [Formula: see text] 0 , whereas none of the moderator variables significantly affected [Formula: see text] 1.
Collapse
Affiliation(s)
- Yuba R Kandel
- Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011, U.S.A
| | - Carl A Bradley
- Department of Plant Pathology, University of Kentucky Research and Education Center, Princeton 42445, U.S.A
| | - Martin I Chilvers
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824, U.S.A
| | - Febina M Mathew
- Department of Agronomy, Horticulture and Plant Science, South Dakota State University, Brookings 57007, U.S.A
| | - Albert U Tenuta
- Ontario Ministry of Agriculture, Food, and Rural Affairs, Ridgetown, ON N0P2C0, Canada
| | - Damon L Smith
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, 53706, U.S.A
| | - Kiersten A Wise
- Department of Plant Pathology, University of Kentucky Research and Education Center, Princeton 42445, U.S.A
| | - Daren S Mueller
- Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011, U.S.A
| |
Collapse
|
13
|
Zhang L, Huang W, Peng D, Liu S. Comparative genomic analyses of two segregating mutants reveal seven genes likely involved in resistance to Fusarium equiseti in soybean via whole genome re-sequencing. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2019; 132:2997-3008. [PMID: 31338526 DOI: 10.1007/s00122-019-03401-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 07/11/2019] [Indexed: 06/10/2023]
Abstract
KEY MESSAGE The candidate genes involved in resistance to Fusarium equiseti in soybean PI 437654 were identified through comparative genomic analyses of mutants via whole genome re-sequencing. The fungus Fusarium infects each stage of the growth and development of soybean and causes soybean (Glycine max (L.)) seed and root rot and seedling damping-off and wilt with a large quantity of annual yield loss worldwide. It is very important to identify the resistant genes in soybean to prevent and control this pathogen. One Fusarium equiseti isolate was previously identified to be incompatible with 'PI 437654' but compatible with a Chinese soybean cultivar 'Zhonghuang 13'. In this study, with the infection of this isolate on the seedling roots of developed PI 437654 mutants, 6 mutants were identified from 500 mutants to significantly alter their phenotypes to F. equiseti compared to wild-type PI 437654. Then, two identified segregating mutants were selected to directly perform whole genome re-sequencing. Finally, through comparative genomic analyses 7 genes including one cluster of 4 nucleotide binding site-leucine-rich repeat genes on one genomic region of chromosome 7, a 60S ribosomal protein L12 gene and 2 uncharacterized genes were identified to be likely involved in the resistance to F. equiseti. These genes will facilitate the breeding of resistant germplasm resources and the identification of resistance of soybean to Fusarium spp.
Collapse
Affiliation(s)
- Liuping Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China
| | - Wenkun Huang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China
| | - Deliang Peng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China
| | - Shiming Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China.
- College of Plant Protection, Hunan Agricultural University, Changsha, 410128, People's Republic of China.
| |
Collapse
|
14
|
Roth MG, Noel ZA, Wang J, Warner F, Byrne AM, Chilvers MI. Predicting Soybean Yield and Sudden Death Syndrome Development Using At-Planting Risk Factors. PHYTOPATHOLOGY 2019; 109:1710-1719. [PMID: 31090498 DOI: 10.1094/phyto-02-19-0040-r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In the United States, sudden death syndrome (SDS) of soybean is caused by the fungal pathogen Fusarium virguliforme and is responsible for important yield losses each year. Understanding the risk of SDS development and subsequent yield loss could provide growers with valuable information for management of this challenging disease. Current management strategies for F. virguliforme use partially resistant cultivars, fungicide seed treatments, and extended crop rotations with diverse crops. The aim of this study was to develop models to predict SDS severity and soybean yield loss using at-planting risk factors to integrate with current SDS management strategies. In 2014 and 2015, field studies were conducted in adjacent fields in Decatur, MI, which were intensively monitored for F. virguliforme and nematode quantities at-planting, plant health throughout the growing season, end-of-season SDS severity, and yield using an unbiased grid sampling scheme. In both years, F. virguliforme and soybean cyst nematode (SCN) quantities were unevenly distributed throughout the field. The distribution of F. virguliforme at-planting had a significant correlation with end-of-season SDS severity in 2015, and a significant correlation to yield in 2014 (P < 0.05). SCN distributions at-planting were significantly correlated with end-of-season SDS severity and yield in 2015 (P < 0.05). Prediction models developed through multiple linear regression showed that F. virguliforme abundance (P < 0.001), SCN egg quantity (P < 0.001), and year (P < 0.01) explained the most variation in end-of-season SDS (R2 = 0.32), whereas end-of-season SDS (P < 0.001) and end-of-season root dry weight (P < 0.001) explained the most variation in soybean yield (R2 = 0.53). Further, multivariate analyses support a synergistic relationship between F. virguliforme and SCN, enhancing the severity of foliar SDS. These models indicate that it is possible to predict patches of SDS severity using at-planting risk factors. Verifying these models and incorporating additional data types may help improve SDS management and forecast soybean markets in response to SDS threats.
Collapse
Affiliation(s)
- Mitchell G Roth
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824
- Genetics Program, Michigan State University, East Lansing, MI 48824
| | - Zachary A Noel
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824
- Program in Ecology, Evolutionary Biology and Behavior, Michigan State University, East Lansing, MI 48824
| | - Jie Wang
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824
| | - Fred Warner
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824
| | - Adam M Byrne
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824
| | - Martin I Chilvers
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824
- Genetics Program, Michigan State University, East Lansing, MI 48824
- Program in Ecology, Evolutionary Biology and Behavior, Michigan State University, East Lansing, MI 48824
| |
Collapse
|
15
|
Kandel YR, Bradley CA, Chilvers MI, Mathew FM, Tenuta AU, Smith DL, Wise KA, Mueller DS. Effect of Seed Treatment and Foliar Crop Protection Products on Sudden Death Syndrome and Yield of Soybean. PLANT DISEASE 2019; 103:1712-1720. [PMID: 31059383 DOI: 10.1094/pdis-12-18-2199-re] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Sudden death syndrome (SDS), caused by Fusarium virguliforme, is an important soilborne disease of soybean. Risk of SDS increases when cool and wet conditions occur soon after planting. Recently, multiple seed treatment and foliar products have been registered and advertised for management of SDS but not all have been tested side by side in the same field experiment at multiple field locations. In 2015 and 2016, seed treatment fungicides fluopyram and thiabendazole; seed treatment biochemical pesticides citric acid and saponins extract of Chenopodium quinoa; foliar fungicides fluoxastrobin + flutriafol; and an herbicide, lactofen, were evaluated in Illinois, Indiana, Iowa, Michigan, South Dakota, Wisconsin, and Ontario for SDS management. Treatments were tested on SDS-resistant and -susceptible cultivars at each location. Overall, fluopyram provided the highest level of control of root rot and foliar symptoms of SDS among all the treatments. Foliar application of lactofen reduced foliar symptoms in some cases but produced the lowest yield. In 2015, fluopyram reduced the foliar disease index (FDX) by over 50% in both resistant and susceptible cultivars and provided 8.9% yield benefit in susceptible cultivars and 3.5% yield benefit in resistant cultivars compared with the base seed treatment (control). In 2016, fluopyram reduced FDX in both cultivars by over 40% compared with the base seed treatment. For yield in 2016, treatment effect was not significant in the susceptible cultivar while, in the resistant cultivar, fluopyram provided 3.5% greater yield than the base seed treatment. In this study, planting resistant cultivars and using fluopyram seed treatment were the most effective tools for SDS management. However, plant resistance provided an overall better yield-advantage than using fluopyram seed treatment alone. Effective seed treatments can be an economically viable consideration to complement resistant cultivars for managing SDS.
Collapse
Affiliation(s)
- Yuba R Kandel
- 1 Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011, U.S.A
| | - Carl A Bradley
- 2 Department of Plant Pathology, University of Kentucky Research and Education Center, Princeton 42445, U.S.A
| | - Martin I Chilvers
- 3 Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824, U.S.A
| | - Febina M Mathew
- 4 Department of Agronomy, Horticulture and Plant Science, South Dakota State University, Brookings 57007, U.S.A
| | - Albert U Tenuta
- 5 Ontario Ministry of Agriculture, Food, and Rural Affairs, Ridgetown, ON N0P2C0, Canada
| | - Damon L Smith
- 6 Department of Plant Pathology, University of Wisconsin-Madison, Madison, 53706, U.S.A
| | - Kiersten A Wise
- 2 Department of Plant Pathology, University of Kentucky Research and Education Center, Princeton 42445, U.S.A
| | - Daren S Mueller
- 1 Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011, U.S.A
| |
Collapse
|
16
|
Roth MG, Chilvers MI. A protoplast generation and transformation method for soybean sudden death syndrome causal agents Fusarium virguliforme and F. brasiliense. Fungal Biol Biotechnol 2019; 6:7. [PMID: 31123591 PMCID: PMC6518667 DOI: 10.1186/s40694-019-0070-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 04/23/2019] [Indexed: 11/29/2022] Open
Abstract
Background Soybean production around the globe faces significant annual yield losses due to pests and diseases. One of the most significant causes of soybean yield loss annually in the U.S. is sudden death syndrome (SDS), caused by soil-borne fungi in the Fusarium solani species complex. Two of these species, F. virguliforme and F. brasiliense, have been discovered in the U.S. The genetic mechanisms that these pathogens employ to induce root rot and SDS are largely unknown. Previous methods describing F. virguliforme protoplast generation and transformation have been used to study gene function, but these methods lack important details and controls. In addition, no reports of protoplast generation and genetic transformation have been made for F. brasiliense. Results We developed a new protocol for developing fungal protoplasts in these Fusarium species and test the protoplasts for the ability to take up foreign DNA. We show that wild-type strains of F. virguliforme and F. brasiliense are sensitive to the antibiotics hygromycin and nourseothricin, but strains transformed with resistance genes displayed resistance to these antibiotics. In addition, integration of fluorescent protein reporter genes demonstrates that the foreign DNA is expressed and results in a functional protein, providing fluorescence to both pathogens. Conclusions This protocol provides significant details for reproducibly producing protoplasts and transforming F. virguliforme and F. brasiliense. The protocol can be used to develop high quality protoplasts for further investigations into genetic mechanisms of growth and pathogenicity of F. virguliforme and F. brasiliense. Fluorescent strains developed in this study can be used to investigate temporal colonization and potential host preferences of these species. Electronic supplementary material The online version of this article (10.1186/s40694-019-0070-0) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Mitchell G Roth
- 1Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue St., East Lansing, 48824 MI USA.,2Genetics Graduate Program, Michigan State University, 567 Wilson Rd., East Lansing, 48824 MI USA
| | - Martin I Chilvers
- 1Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue St., East Lansing, 48824 MI USA.,2Genetics Graduate Program, Michigan State University, 567 Wilson Rd., East Lansing, 48824 MI USA
| |
Collapse
|
17
|
Swaminathan S, Das A, Assefa T, Knight JM, Da Silva AF, Carvalho JPS, Hartman GL, Huang X, Leandro LF, Cianzio SR, Bhattacharyya MK. Genome wide association study identifies novel single nucleotide polymorphic loci and candidate genes involved in soybean sudden death syndrome resistance. PLoS One 2019; 14:e0212071. [PMID: 30807585 PMCID: PMC6391044 DOI: 10.1371/journal.pone.0212071] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 01/25/2019] [Indexed: 01/17/2023] Open
Abstract
Fusarium virguliforme is a soil borne root pathogen that causes sudden death syndrome (SDS) in soybean [Glycine max (L.) Merrill]. Once the fungus invades the root xylem tissues, the pathogen secretes toxins that cause chlorosis and necrosis in foliar tissues leading to defoliation, flower and pod drop and eventually death of plants. Resistance to F. virguliforme in soybean is partial and governed by over 80 quantitative trait loci (QTL). We have conducted genome-wide association study (GWAS) for a group of 254 plant introductions lines using a panel of approximately 30,000 SNPs and identified 19 single nucleotide polymorphic loci (SNPL) that are associated with 14 genomic regions encoding foliar SDS and eight SNPL associated with seven genomic regions for root rot resistance. Of the identified 27 SNPL, six SNPL for foliar SDS resistance and two SNPL for root rot resistance co-mapped to previously identified QTL for SDS resistance. This study identified 13 SNPL associated with eight novel genomic regions containing foliar SDS resistance genes and six SNPL with five novel regions for root-rot resistance. This study identified five genes carrying nonsynonymous mutations: (i) three of which mapped to previously identified QTL for foliar SDS resistance and (ii) two mapped to two novel regions containing root rot resistance genes. Of the three genes mapped to QTL for foliar SDS resistance genes, two encode LRR-receptors and third one encodes a novel protein with unknown function. Of the two genes governing root rot resistance, Glyma.01g222900.1 encodes a soybean-specific LEA protein and Glyma.10g058700.1 encodes a heparan-alpha-glucosaminide N-acetyltransferase. In the LEA protein, a conserved serine residue was substituted with asparagine; and in the heparan-alpha-glucosaminide N-acetyltransferase, a conserved histidine residue was substituted with an arginine residue. Such changes are expected to alter functions of these two proteins regulated through phosphorylation. The five genes with nonsynonymous mutations could be considered candidate SDS resistance genes and should be suitable molecular markers for breeding SDS resistance in soybean. The study also reports desirable plant introduction lines and novel genomic regions for enhancing SDS resistance in soybean.
Collapse
Affiliation(s)
| | - Anindya Das
- Department of Computer Science, Iowa State University, Ames, Iowa, United States of America
| | - Teshale Assefa
- Department of Agronomy, Iowa State University, Ames, Iowa, United States of America
| | - Joshua M. Knight
- Department of Agronomy, Iowa State University, Ames, Iowa, United States of America
| | | | - João P. S. Carvalho
- Department of Agronomy, Iowa State University, Ames, Iowa, United States of America
| | - Glen L. Hartman
- USDA and Department of Crop Sciences, University of Illinois, Urbana, Illinois, United States of America
| | - Xiaoqiu Huang
- Department of Computer Science, Iowa State University, Ames, Iowa, United States of America
| | - Leonor F. Leandro
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, Iowa, United States of America
| | - Silvia R. Cianzio
- Department of Agronomy, Iowa State University, Ames, Iowa, United States of America
| | | |
Collapse
|
18
|
Tan R, Collins PJ, Wang J, Wen Z, Boyse JF, Laurenz RG, Gu C, Jacobs JL, Song Q, Chilvers MI, Wang D. Different loci associated with root and foliar resistance to sudden death syndrome (Fusarium virguliforme) in soybean. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2019; 132:501-513. [PMID: 30446796 DOI: 10.1007/s00122-018-3237-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 11/09/2018] [Indexed: 06/09/2023]
Abstract
KEY MESSAGE Different loci associated with root resistance to F. virguliforme colonization and foliar resistance to phytotoxin damage in soybean. Use of resistant cultivars is the most efficacious approach to manage soybean sudden death syndrome (SDS), caused by Fusarium virguliforme. The objectives of this study were to (1) map the loci associated with root and foliar resistance to F. virguliforme infection and (2) decipher the relationships between root infection, foliar damage, and plot yield. A mapping population consisting of 153 F4-derived recombinant inbred lines from the cross U01-390489 × E07080 was genotyped by SoySNP6 K BeadChip assay. Both foliar damage and F. virguliforme colonization in roots were investigated in the field, and a weak positive correlation was identified between them. Foliar damage had a stronger negative correlation with plot yield than F. virguliforme colonization. Twelve loci associated with foliar damage were identified, and four of them were associated with multiple traits across environments. In contrast, only one locus associated with root resistance to F. virguliforme colonization was identified and mapped on Chromosome 18. It colocalized with the locus associated with foliar damage in the same environment. The locus on Chromosome 6, qSDS6-2, and the locus on Chromosome 18, qSDS18-1, were associated with resistance to SDS phytotoxins and resistance to F. virguliforme colonization of roots, respectively. Both loci affected plot yield. Foliar damage-related traits, especially disease index, are valuable indicators for SDS resistance breeding because of consistency of the identified loci and their stronger correlation with plot yield. The information provided by this study will facilitate marker-assisted selection to improve SDS resistance in soybean.
Collapse
Affiliation(s)
- Ruijuan Tan
- Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue St., East Lansing, MI, 48824-1325, USA
| | - Paul J Collins
- Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue St., East Lansing, MI, 48824-1325, USA
| | - Jie Wang
- Department of Plant Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Zixiang Wen
- Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue St., East Lansing, MI, 48824-1325, USA
| | - John F Boyse
- Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue St., East Lansing, MI, 48824-1325, USA
| | - Randall G Laurenz
- Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue St., East Lansing, MI, 48824-1325, USA
| | - Cuihua Gu
- Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue St., East Lansing, MI, 48824-1325, USA
| | - Janette L Jacobs
- Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue St., East Lansing, MI, 48824-1325, USA
| | - Qijian Song
- Soybean Genomics and Improvement Laboratory, Agricultural Research Service, United States Department of Agriculture, Beltsville, Maryland, 20705, USA
| | - Martin I Chilvers
- Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue St., East Lansing, MI, 48824-1325, USA
| | - Dechun Wang
- Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue St., East Lansing, MI, 48824-1325, USA.
| |
Collapse
|
19
|
Rosati RG, Lario LD, Hourcade ME, Cervigni GDL, Luque AG, Scandiani MM, Spampinato CP. Primary metabolism changes triggered in soybean leaves by Fusarium tucumaniae infection. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 274:91-100. [PMID: 30080645 DOI: 10.1016/j.plantsci.2018.05.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 05/16/2018] [Accepted: 05/17/2018] [Indexed: 06/08/2023]
Abstract
Sudden death syndrome (SDS) of soybean can be caused by at least four distinct Fusarium species, with F. tucumaniae being the main causal agent in Argentina. The fungus is a soil-borne pathogen that is largely confined to the roots, but damage also reaches aerial part of the plant and interveinal chlorosis and necrosis, followed by premature defoliation can be observed. In this study, two genetically diverse soybean cultivars, one susceptible (NA 4613) and one partially resistant (DM 4670) to SDS infection, were inoculated with F. tucumaniae or kept uninoculated. Leaf samples at 7, 10, 14 and 25 days post-inoculation (dpi) were chosen for analysis. With the aim of detecting early markers that could potentially discriminate the cultivar response to SDS, gas chromatography-mass spectrometry (GC-MS) analyses and biochemical studies were performed. Metabolic analyses show higher levels of several amino acids in the inoculated than in the uninoculated susceptible cultivar starting at 10 dpi. Biochemical studies indicate that pigment contents and Rubisco level were reduced while class III peroxidase activity was increased in the inoculated susceptible plant at 10 dpi. Taken together, our results indicate that the pathogen induced an accumulation of amino acids, a decrease of the photosynthetic activity, and an increase of plant-specific peroxidase activity in the susceptible cultivar before differences of visible foliar symptoms between genotypes could be observed, thus suggesting that metabolic and biochemical approaches may contribute to a rapid characterization of the cultivar response to SDS.
Collapse
Affiliation(s)
- Romina G Rosati
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina
| | - Luciana D Lario
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina
| | - Mónica E Hourcade
- Laboratorio de Cromatografía Gaseosa y Espectrometría de Masas, Sala de Instrumental Central, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina
| | - Gerardo D L Cervigni
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina
| | - Alicia G Luque
- Centro de Referencia de Micología (CEREMIC), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina
| | - María M Scandiani
- Centro de Referencia de Micología (CEREMIC), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina
| | - Claudia P Spampinato
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina.
| |
Collapse
|
20
|
Leandro LFS, Eggenberger S, Chen C, Williams J, Beattie GA, Liebman M. Cropping System Diversification Reduces Severity and Incidence of Soybean Sudden Death Syndrome Caused by Fusarium virguliforme. PLANT DISEASE 2018; 102:1748-1758. [PMID: 30125211 DOI: 10.1094/pdis-11-16-1660-re] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Current management of sudden death syndrome (SDS) of soybean, caused by Fusarium virguliforme, focuses on planting resistant varieties and improving soil drainage; however, these measures are not completely effective. A 6-year study evaluated the effects of cropping system diversification on SDS and soybean yield. SDS, root health, yield, and F. virguliforme density in soil were assessed in a naturally infested field trial comparing a 2-year cropping system consisting of a corn-soybean rotation and synthetic fertilizer applications with 3- and 4-year cropping systems consisting of corn-soybean-oat + red clover and corn-soybean-oat +alfalfa-alfalfa rotations, respectively, with both manure and low synthetic fertilizer rates. In 5 of 6 years, SDS incidence and severity were lower and yield higher in the 3- and 4-year systems than in the 2-year system. SDS severity and incidence were up to 17-fold lower in the diversified systems than in the 2-year system. Incidence and severity of SDS explained 45 to 87% of the variation in yield. Plants in the 2-year system generally showed more severe root rot and lower plant weights than plants in the diversified systems. F. virguliforme density in soil was up to fivefold greater in the 2-year system compared with the 4-year system. The processes responsible for the suppression of SDS and yield protection in the diversified cropping systems still need to be determined.
Collapse
Affiliation(s)
| | | | - C Chen
- Department of Plant Pathology and Microbiology
| | - J Williams
- Department of Plant Pathology and Microbiology
| | - G A Beattie
- Department of Plant Pathology and Microbiology
| | - M Liebman
- Department of Agronomy, Iowa State University, Ames 50011
| |
Collapse
|
21
|
Kandel YR, McCarville MT, Adee EA, Bond JP, Chilvers MI, Conley SP, Giesler LJ, Kelly HM, Malvick DK, Mathew FM, Rupe JC, Sweets LE, Tenuta AU, Wise KA, Mueller DS. Benefits and Profitability of Fluopyram-Amended Seed Treatments for Suppressing Sudden Death Syndrome and Protecting Soybean Yield: A Meta-Analysis. PLANT DISEASE 2018; 102:1093-1100. [PMID: 30673444 DOI: 10.1094/pdis-10-17-1540-re] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A meta-analytic approach was used to summarize data on the effects of fluopyram-amended seed treatment on sudden death syndrome (SDS) and yield of soybean (Glycine max L.) in over 200 field trials conducted in 12 U.S. states and Ontario, Canada from 2013 to 2015. In those trials, two treatments-the commercial base (CB), and CB plus fluopyram (CBF)-were tested, and all disease and yield data were combined to conduct a random-effects and mixed-effects meta-analysis (test of moderators) to estimate percent control and yield response relative to CB. Overall, a 35% reduction in foliar disease and 295 kg/ha (7.6%) increase in yield were estimated for CBF relative to CB. Sowing date and geographic region affected both estimates. The variation in yield response was explained partially by disease severity (19%), geographic region (8%), and sowing date (10%) but not by the resistance level of the cultivar. The probability of not offsetting the cost of fluopyram was estimated on a range of grain prices and treatment cost combinations. There was a high probability (>80%) of yield gains when disease level was high in any cost-price combinations tested but very low when the foliar symptoms of the disease were absent.
Collapse
Affiliation(s)
- Yuba R Kandel
- Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011
| | | | - Eric A Adee
- Department of Agronomy, Kansas State University, Manhattan 66506
| | - Jason P Bond
- Department of Plant, Soil and Agricultural Systems, Southern Illinois University, Carbondale 62901
| | - Martin I Chilvers
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824
| | - Shawn P Conley
- Department of Agronomy, University of Wisconsin, Madison 53706
| | - Loren J Giesler
- Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln 68508
| | - Heather M Kelly
- Entomology and Plant Pathology Department, University of Tennessee, Jackson 38301
| | - Dean K Malvick
- Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - Febina M Mathew
- Department of Agronomy, Horticulture and Plant Science, South Dakota State University, Brookings 57007
| | - John C Rupe
- Department of Plant Pathology, University of Arkansas, Fayetteville 72701
| | - Laura E Sweets
- Division of Plant Sciences, University of Missouri, Columbia 65211
| | - Albert U Tenuta
- Ontario Ministry of Agriculture, Food, and Rural Affairs, Ridgetown, ON N0P2C0, Canada
| | - Kiersten A Wise
- Department of Plant Pathology, University of Kentucky, Princeton 42445
| | - Daren S Mueller
- Department of Plant Pathology and Microbiology, Iowa State University, Ames
| |
Collapse
|
22
|
Swaminathan S, Abeysekara NS, Knight JM, Liu M, Dong J, Hudson ME, Bhattacharyya MK, Cianzio SR. Mapping of new quantitative trait loci for sudden death syndrome and soybean cyst nematode resistance in two soybean populations. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2018; 131:1047-1062. [PMID: 29582113 DOI: 10.1007/s00122-018-3057-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 01/12/2018] [Indexed: 05/07/2023]
Abstract
KEY MESSAGE Novel QTL conferring resistance to both the SDS and SCN was detected in two RIL populations. Dual resistant RILs could be used in breeding programs for developing resistant soybean cultivars. Soybean cultivars, susceptible to the fungus Fusarium virguliforme, which causes sudden death syndrome (SDS), and to the soybean cyst nematode (SCN) (Heterodera glycines), suffer yield losses valued over a billion dollars annually. Both pathogens may occur in the same production fields. Planting of cultivars genetically resistant to both pathogens is considered one of the most effective means to control the two pathogens. The objective of the study was to map quantitative trait loci (QTL) underlying SDS and SCN resistances. Two recombinant inbred line (RIL) populations were developed by crossing 'A95-684043', a high-yielding maturity group (MG) II line resistant to SCN, with 'LS94-3207' and 'LS98-0582' of MG IV, resistant to both F. virguliforme and SCN. Two hundred F7 derived recombinant inbred lines from each population AX19286 (A95-684043 × LS94-3207) and AX19287 (A95-684043 × LS98-0582) were screened for resistance to each pathogen under greenhouse conditions. Five hundred and eighty and 371 SNP markers were used for mapping resistance QTL in each population. In AX19286, one novel SCN resistance QTL was mapped to chromosome 8. In AX19287, one novel SDS resistance QTL was mapped to chromosome 17 and one novel SCN resistance QTL was mapped to chromosome 11. Previously identified additional SDS and SCN resistance QTL were also detected in the study. Lines possessing superior resistance to both pathogens were also identified and could be used as germplasm sources for breeding SDS- and SCN-resistant soybean cultivars.
Collapse
Affiliation(s)
| | - Nilwala S Abeysekara
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, 50011, USA
- Department of Plant Pathology and Microbiology, University of California, Riverside, CA, 92507, USA
| | - Joshua M Knight
- Department of Agronomy, Iowa State University, Ames, IA, 50011, USA
| | - Min Liu
- Department of Agronomy, Iowa State University, Ames, IA, 50011, USA
- Department of Agronomy, Shenyang Agricultural University, 120 Dongling Ave, Shenyang, 110866, Liaoning, China
| | - Jia Dong
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Matthew E Hudson
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | | | - Silvia R Cianzio
- Department of Agronomy, Iowa State University, Ames, IA, 50011, USA.
| |
Collapse
|
23
|
Chang HX, Roth MG, Wang D, Cianzio SR, Lightfoot DA, Hartman GL, Chilvers MI. Integration of sudden death syndrome resistance loci in the soybean genome. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2018; 131:757-773. [PMID: 29435603 DOI: 10.1007/s00122-018-3063-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 01/19/2018] [Indexed: 05/12/2023]
Abstract
KEY MESSAGE Complexity and inconsistencies in resistance mapping publications of soybean sudden death syndrome (SDS) result in interpretation difficulty. This review integrates SDS mapping literature and proposes a new nomenclature system for reproducible SDS resistance loci. Soybean resistance to sudden death syndrome (SDS) is composed of foliar resistance to phytotoxins and root resistance to pathogen invasion. There are more than 80 quantitative trait loci (QTL) and dozens of single nucleotide polymorphisms (SNPs) associated with soybean resistance to SDS. The validity of these QTL and SNPs is questionable because of the complexity in phenotyping methodologies, the disease synergism between SDS and soybean cyst nematode (SCN), the variability from the interactions between soybean genotypes and environments, and the inconsistencies in the QTL nomenclature. This review organizes SDS mapping results and proposes the Rfv (resistance to Fusarium virguliforme) nomenclature based on supporting criteria described in the text. Among ten reproducible loci receiving our Rfv nomenclature, Rfv18-01 is mostly supported by field studies and it co-localizes to the SCN resistance locus rhg1. The possibility that Rfv18-01 is a pleiotropic resistance locus and the concern about Rfv18-01 being confounded with Rhg1 is discussed. On the other hand, Rfv06-01, Rfv06-02, Rfv09-01, Rfv13-01, and Rfv16-01 were identified both by screening soybean leaves against phytotoxic culture filtrates and by evaluating SDS severity in fields. Future phenotyping using leaf- and root-specific resistance screening methodologies may improve the precision of SDS resistance, and advanced genetic studies may further clarify the interactions among soybean genotypes, F. virguliforme, SCN, and environments. The review provides a summary of the SDS resistance literature and proposes a framework for communicating SDS resistance loci for future research considering molecular interactions and genetic breeding for soybean SDS resistance.
Collapse
Affiliation(s)
- Hao-Xun Chang
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, USA
| | - Mitchell G Roth
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, USA
- Genetics Program, Michigan State University, East Lansing, MI, USA
| | - Dechun Wang
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, USA
| | | | - David A Lightfoot
- Department of Plant, Soil and Agricultural Systems, Southern Illinois University, Carbondale, IL, USA.
| | - Glen L Hartman
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
- USDA-Agricultural Research Service, Urbana, IL, USA.
| | - Martin I Chilvers
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, USA.
- Genetics Program, Michigan State University, East Lansing, MI, USA.
| |
Collapse
|
24
|
Leaf and Canopy Level Detection of Fusarium Virguliforme (Sudden Death Syndrome) in Soybean. REMOTE SENSING 2018. [DOI: 10.3390/rs10030426] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
25
|
Luckew AS, Swaminathan S, Leandro LF, Orf JH, Cianzio SR. 'MN1606SP' by 'Spencer' filial soybean population reveals novel quantitative trait loci and interactions among loci conditioning SDS resistance. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2017; 130:2139-2149. [PMID: 28748252 DOI: 10.1007/s00122-017-2947-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 07/08/2017] [Indexed: 06/07/2023]
Abstract
KEY MESSAGE Four novel QTL and interactions among QTL were identified in this research, using as a parent line the most SDS-resistant genotype within soybean cultivars of the US early maturity groups. Soybean sudden death syndrome (SDS) reduces soybean yield in most of the growing areas of the world. The causal agent of SDS, soilborne fungus Fusarium virguliforme (Fv), releases phytotoxins taken up by the plant to produce chlorosis and necrosis in the leaves. Planting resistant cultivars is the most successful management practice to control the disease. The objective of this study was to identify quantitative trait loci (QTL) associated with the resistance response of MN1606SP to SDS. A mapping population of F 2:3 lines created by crossing the highly resistant cultivar 'MN1606SP' and the susceptible cultivar 'Spencer' was phenotyped in the greenhouse at three different planting times, each with three replications. Plants were artificially inoculated using SDS infested sorghum homogeneously mixed with the soil. Data were collected on three disease criteria, foliar disease incidence (DI), foliar leaf scorch disease severity (DS), and root rot severity. Disease index (DX) was calculated as DI × DS. Ten QTL were identified for the different disease assessment criteria, three for DI, four for DX, and three for root rot severity. Three QTL identified for root rot severity and one QTL for disease incidence are considered novel, since no previous reports related to these QTL are available. Among QTL, two interactions were detected between four different QTL. The interactions suggest that resistance to SDS is not only dependent on additive gene effects. The novel QTL and the interactions observed in this study will be useful to soybean breeders for improvement of SDS resistance in soybean germplasm.
Collapse
Affiliation(s)
| | | | - Leonor F Leandro
- Department of Plant Pathology, Iowa State University, Ames, IA, 50011, USA
| | - James H Orf
- Department Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN, 55108, USA
| | - Silvia R Cianzio
- Department of Agronomy, Iowa State University, Ames, IA, 50011, USA.
| |
Collapse
|
26
|
Islam KT, Bond JP, Fakhoury AM. FvSNF1, the sucrose non-fermenting protein kinase gene of Fusarium virguliforme, is required for cell-wall-degrading enzymes expression and sudden death syndrome development in soybean. Curr Genet 2017; 63:723-738. [PMID: 28132080 DOI: 10.1007/s00294-017-0676-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 12/29/2016] [Accepted: 01/06/2017] [Indexed: 01/17/2023]
Abstract
Fusarium virguliforme is a soil-borne pathogenic fungus that causes sudden death syndrome (SDS) in soybean. Its pathogenicity is believed to require the activity of cell-wall-degrading enzymes (CWDEs). The sucrose non-fermenting protein kinase 1 gene (SNF1) is a key component of the glucose de-repression pathway in yeast, and a regulator of gene expression for CWDEs in some plant pathogenic fungi. To elucidate the functional role of the SNF1 homolog in F. virguliforme, FvSNF1 was disrupted using a split-marker strategy. Disruption of FvSNF1 in F. virguliforme abolishes galactose utilization and causes poor growth on xylose, arabinose and sucrose. However, the resulting Fvsnf1 mutant grew similar to wild-type and ectopic transformants on glucose, fructose, maltose, or pectin as the main source of carbon. The Fvsnf1 mutant displayed no expression of the gene-encoding galactose oxidase (GAO), a secretory enzyme that catalyzes oxidation of D-galactose. It also exhibited a significant reduction in the expression of several CWDE-coding genes in contrast to the wild-type strain. Greenhouse pathogenicity assays revealed that the Fvsnf1 mutant was severely impaired in its ability to cause SDS on challenged soybean plants. Microscopy and microtome studies on infected roots showed that the Fvsnf1 mutant was defective in colonizing vascular tissue of infected plants. Cross and longitudinal sections of infected roots stained with fluorescein-labeled wheat germ agglutinin and Congo red showed that the Fvsnf1 mutant failed to colonize the xylem vessels and phloem tissue at later stages of infection. Quantification of the fungal biomass in inoculated roots further confirmed a reduced colonization of roots by the Fvsnf1 mutant when compared to the wild type. These findings suggest that FvSNF1 regulates the expression of CWDEs in F. virguliforme, thus affecting the virulence of the fungus on soybean.
Collapse
Affiliation(s)
- Kazi T Islam
- Department of Plant, Soil and Agriculture Systems, Southern Illinois University, Carbondale, IL, 62901, USA
- Donald Danforth Plant Science Center, St Louis, MO, 63132, USA
| | - Jason P Bond
- Department of Plant, Soil and Agriculture Systems, Southern Illinois University, Carbondale, IL, 62901, USA
| | - Ahmad M Fakhoury
- Department of Plant, Soil and Agriculture Systems, Southern Illinois University, Carbondale, IL, 62901, USA.
| |
Collapse
|
27
|
Islam KT, Bond JP, Fakhoury AM. FvSTR1, a striatin orthologue in Fusarium virguliforme, is required for asexual development and virulence. Appl Microbiol Biotechnol 2017; 101:6431-6445. [PMID: 28643182 DOI: 10.1007/s00253-017-8387-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 06/07/2017] [Accepted: 06/10/2017] [Indexed: 02/07/2023]
Abstract
The soil-borne fungus Fusarium virguliforme causes sudden death syndrome (SDS), one of the most devastating diseases of soybean in North and South America. Despite the importance of SDS, a clear understanding of the fungal pathogenicity factors that affect the development of this disease is still lacking. We have identified FvSTR1, a F. virguliforme gene, which encodes a protein similar to a family of striatin proteins previously reported to regulate signalling pathways, cell differentiation, conidiation, sexual development, and virulence in filamentous fungi. Striatins are multi-domain proteins that serve as scaffolding units in the striatin-interacting phosphatase and kinase (STRIPAK) complex in fungi and animals. To address the function of a striatin homologue in F. virguliforme, FvSTR1 was disrupted and functionally characterized using a gene knock out strategy. The resulting Fvstr1 mutants were largely impaired in conidiation and pigmentation, and displayed defective conidia and conidiophore morphology compared to the wild-type and ectopic transformants. Greenhouse virulence assays revealed that the disruption of FvSTR1 resulted in complete loss of virulence in F. virguliforme. Microtome studies using fluorescence microscopy showed that the Fvstr1 mutants were defective in their ability to colonize the vascular system. The Fvstr1 mutants also showed a reduced transcript level of genes involved in asexual reproduction and in the production of secondary metabolites. These results suggest that FvSTR1 has a critical role in asexual development and virulence in F. virguliforme.
Collapse
Affiliation(s)
- Kazi T Islam
- Department of Plant, Soil and Agriculture Systems, Southern Illinois University, Carbondale, IL, 62901, USA
- Donald Danforth Plant Science Center, St Louis, MO, 63132, USA
| | - Jason P Bond
- Department of Plant, Soil and Agriculture Systems, Southern Illinois University, Carbondale, IL, 62901, USA
| | - Ahmad M Fakhoury
- Department of Plant, Soil and Agriculture Systems, Southern Illinois University, Carbondale, IL, 62901, USA.
| |
Collapse
|
28
|
Abdelsamad NA, Baumbach J, Bhattacharyya MK, Leandro LF. Soybean Sudden Death Syndrome Caused by Fusarium virguliforme is Impaired by Prolonged Flooding and Anaerobic Conditions. PLANT DISEASE 2017; 101:712-719. [PMID: 30678564 DOI: 10.1094/pdis-04-16-0534-re] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
High soil moisture usually favors soybean sudden death syndrome (SDS), caused by Fusarium virguliforme (Fv), but the effects of the duration of the flooding period and accompanying anaerobic conditions on the soybean-Fv interaction are not clear. Greenhouse studies were conducted using susceptible and resistant cultivars exposed to the following treatments: 3, 5, or 7 days of continuous flooding, repeated short-term flooding of 8 h/week for 3 weeks, and a no-flood check treatment. At 7, 14, and 21 days after flooding (DAF), seedlings in the no-flood, 3-day, and repeated short-term treatments showed the highest root rot and foliar symptom severity, whereas seedlings in the 7-day treatment showed the lowest severity. Fv inoculum density in soil was lowest in the 7-day flooding treatment. In a hydroponic system, the steady transcript levels of soybean defense genes and Fv candidate virulence genes were measured in response to different oxygen levels using qPCR. Fv-infected roots exposed to 12 h of anaerobic conditions showed down-regulation of the defense-related soybean genes Laccase, PR3, PR10, PAL, and CHS, and the Fv virulence genes pectate lyase (PL), and Fv homolog of the pisatin demethylase (PDA). Our study suggests that short-term flooding tends to increase SDS, while prolonged flooding negatively impacts SDS due to reduction of Fv density in soil. Moreover, anaerobic conditions down-regulate both soybean defense genes and Fv candidate virulence genes.
Collapse
Affiliation(s)
| | | | | | - L F Leandro
- Department of Plant Pathology and Microbiology, Iowa State University, Ames 50010
| |
Collapse
|
29
|
Sahu BB, Baumbach JL, Singh P, Srivastava SK, Yi X, Bhattacharyya MK. Investigation of the Fusarium virguliforme Transcriptomes Induced during Infection of Soybean Roots Suggests that Enzymes with Hydrolytic Activities Could Play a Major Role in Root Necrosis. PLoS One 2017; 12:e0169963. [PMID: 28095498 PMCID: PMC5241000 DOI: 10.1371/journal.pone.0169963] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 12/27/2016] [Indexed: 02/06/2023] Open
Abstract
Sudden death syndrome (SDS) is caused by the fungal pathogen, Fusarium virguliforme, and is a major threat to soybean production in North America. There are two major components of this disease: (i) root necrosis and (ii) foliar SDS. Root symptoms consist of root necrosis with vascular discoloration. Foliar SDS is characterized by interveinal chlorosis and leaf necrosis, and in severe cases by flower and pod abscission. A major toxin involved in initiating foliar SDS has been identified. Nothing is known about how root necrosis develops. In order to unravel the mechanisms used by the pathogen to cause root necrosis, the transcriptome of the pathogen in infected soybean root tissues of a susceptible cultivar, 'Essex', was investigated. The transcriptomes of the germinating conidia and mycelia were also examined. Of the 14,845 predicted F. virguliforme genes, we observed that 12,017 (81%) were expressed in germinating conidia and 12,208 (82%) in mycelia and 10,626 (72%) in infected soybean roots. Of the 10,626 genes induced in infected roots, 224 were transcribed only following infection. Expression of several infection-induced genes encoding enzymes with oxidation-reduction properties suggests that degradation of antimicrobial compounds such as the phytoalexin, glyceollin, could be important in early stages of the root tissue infection. Enzymes with hydrolytic and catalytic activities could play an important role in establishing the necrotrophic phase. The expression of a large number of genes encoding enzymes with catalytic and hydrolytic activities during the late infection stages suggests that cell wall degradation could be involved in root necrosis and the establishment of the necrotrophic phase in this pathogen.
Collapse
Affiliation(s)
- Binod B. Sahu
- Department of Agronomy, Iowa State University, Ames, Iowa, United States of America
| | - Jordan L. Baumbach
- Department of Agronomy, Iowa State University, Ames, Iowa, United States of America
- Interdepartmental Genetic Program, Iowa State University, Ames, Iowa, United States of America
| | - Prashant Singh
- Department of Agronomy, Iowa State University, Ames, Iowa, United States of America
| | - Subodh K. Srivastava
- Department of Agronomy, Iowa State University, Ames, Iowa, United States of America
| | - Xiaoping Yi
- Department of Agronomy, Iowa State University, Ames, Iowa, United States of America
| | - Madan K. Bhattacharyya
- Department of Agronomy, Iowa State University, Ames, Iowa, United States of America
- Interdepartmental Genetic Program, Iowa State University, Ames, Iowa, United States of America
| |
Collapse
|
30
|
Iqbal MJ, Majeed M, Humayun M, Lightfoot DA, Afzal AJ. Proteomic Profiling and the Predicted Interactome of Host Proteins in Compatible and Incompatible Interactions Between Soybean and Fusarium virguliforme. Appl Biochem Biotechnol 2016; 180:1657-1674. [PMID: 27491306 DOI: 10.1007/s12010-016-2194-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 07/13/2016] [Indexed: 12/27/2022]
Abstract
Sudden death syndrome (SDS) is a complex of two diseases of soybean (Glycine max), caused by the soil borne pathogenic fungus Fusarium virguliforme. The root rot and leaf scorch diseases both result in significant yield losses worldwide. Partial SDS resistance has been demonstrated in multiple soybean cultivars. This study aimed to highlight proteomic changes in soybean roots by identifying proteins which are differentially expressed in near isogenic lines (NILs) contrasting at the Rhg1/Rfs2 locus for partial resistance or susceptibility to SDS. Two-dimensional gel electrophoresis resolved approximately 1000 spots on each gel; 12 spots with a significant (P < 0.05) difference in abundance of 1.5-fold or more were picked, trypsin-digested, and analyzed using quadruple time-of-flight tandem mass spectrometry. Several spots contained more than one protein, so that 18 distinct proteins were identified overall. A functional analysis performed to categorize the proteins depicted that the major pathways altered by fungal infection include disease resistance, stress tolerance, and metabolism. This is the first report which identifies proteins whose abundances are altered in response to fungal infection leading to SDS. The results provide valuable information about SDS resistance in soybean plants, and plant partial resistance responses in general. More importantly, several of the identified proteins could be good candidates for the development of SDS-resistant soybean plants.
Collapse
Affiliation(s)
- M Javed Iqbal
- Department of Plant Sciences, University of California, Davis, California, 95616, USA
| | - Maryam Majeed
- Department of Biology, SBA School of Science and Engineering, Lahore University of Management Sciences, Lahore, 54792, Pakistan
- Department of Biological Sciences, Columbia University, New York, NY, 10027, USA
| | - Maheen Humayun
- Department of Biology, SBA School of Science and Engineering, Lahore University of Management Sciences, Lahore, 54792, Pakistan
| | - David A Lightfoot
- Department of Molecular Biology, Microbiology, and Biochemistry, Genomics Core Facility and Center for Excellence in Soybean Research, Teaching, and Outreach, and Department of Plant Biology, Southern Illinois University, Carbondale, Illinois, 62901, USA
| | - Ahmed J Afzal
- Department of Biology, SBA School of Science and Engineering, Lahore University of Management Sciences, Lahore, 54792, Pakistan.
- Department of Molecular Biology, Microbiology, and Biochemistry, Genomics Core Facility and Center for Excellence in Soybean Research, Teaching, and Outreach, and Department of Plant Biology, Southern Illinois University, Carbondale, Illinois, 62901, USA.
| |
Collapse
|
31
|
Ngaki MN, Wang B, Sahu BB, Srivastava SK, Farooqi MS, Kambakam S, Swaminathan S, Bhattacharyya MK. Tanscriptomic Study of the Soybean-Fusarium virguliforme Interaction Revealed a Novel Ankyrin-Repeat Containing Defense Gene, Expression of Whose during Infection Led to Enhanced Resistance to the Fungal Pathogen in Transgenic Soybean Plants. PLoS One 2016; 11:e0163106. [PMID: 27760122 PMCID: PMC5070833 DOI: 10.1371/journal.pone.0163106] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 09/04/2016] [Indexed: 12/13/2022] Open
Abstract
Fusarium virguliforme causes the serious disease sudden death syndrome (SDS) in soybean. Host resistance to this pathogen is partial and is encoded by a large number of quantitative trait loci, each conditioning small effects. Breeding SDS resistance is therefore challenging and identification of single-gene encoded novel resistance mechanisms is becoming a priority to fight this devastating this fungal pathogen. In this transcriptomic study we identified a few putative soybean defense genes, expression of which is suppressed during F. virguliforme infection. The F. virguliforme infection-suppressed genes were broadly classified into four major classes. The steady state transcript levels of many of these genes were suppressed to undetectable levels immediately following F. virguliforme infection. One of these classes contains two novel genes encoding ankyrin repeat-containing proteins. Expression of one of these genes, GmARP1, during F. virguliforme infection enhances SDS resistance among the transgenic soybean plants. Our data suggest that GmARP1 is a novel defense gene and the pathogen presumably suppress its expression to establish compatible interaction.
Collapse
Affiliation(s)
- Micheline N. Ngaki
- Department of Agronomy, Iowa State University, Ames, IA, United States of America
| | - Bing Wang
- Department of Agronomy, Iowa State University, Ames, IA, United States of America
| | - Binod B. Sahu
- Department of Agronomy, Iowa State University, Ames, IA, United States of America
| | - Subodh K. Srivastava
- Department of Agronomy, Iowa State University, Ames, IA, United States of America
| | - Mohammad S. Farooqi
- Department of Agronomy, Iowa State University, Ames, IA, United States of America
| | - Sekhar Kambakam
- Department of Agronomy, Iowa State University, Ames, IA, United States of America
| | | | | |
Collapse
|
32
|
Marburger DA, Smith DL, Conley SP. Revisiting Planting Date and Cultivar Effects on Soybean Sudden Death Syndrome Development and Yield Loss. PLANT DISEASE 2016; 100:2152-2157. [PMID: 30683002 DOI: 10.1094/pdis-12-15-1411-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
The impact of today's optimal planting dates on sudden death syndrome (SDS) (caused by Fusarium virguliforme) development and soybean yield loss are not yet well understood. Field trials established in Hancock, Wisconsin during 2013 and 2014 investigated interactions between planting date and cultivar on SDS development and soybean yield. In 2013, disease index (DX) levels differed among cultivars, but results showed no difference between the 6 May and 24 May planting dates. Significantly lower DX levels were observed for the 17 June date. Greatest yields were found in the 6 May planting date, and yield losses were 720 (17%), 770 (20%), and 400 kg ha-1 (12%) for the 6 May, 24 May, 17 and June planting dates, respectively. In 2014, cultivars again differed for DX, but results showed highest DX levels in the 5 May planting date, with little disease observed in the 22 May and 11 June dates. Yield losses were 400 (12%) and 270 kg ha-1 (9%) for the 5 May and 22 May dates, respectively, but no difference was found in the 11 June date. Despite the most symptom development, these results suggest early May planting coupled with appropriate cultivar selection provides maximum yield potential and profitability in Wisconsin.
Collapse
Affiliation(s)
- David A Marburger
- Department of Agronomy, University of Wisconsin-Madison, 1575 Linden Drive, Madison, WI 53706
| | - Damon L Smith
- Department of Plant Pathology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI 53706
| | | |
Collapse
|
33
|
Kandel YR, Wise KA, Bradley CA, Tenuta AU, Mueller DS. Effect of Planting Date, Seed Treatment, and Cultivar on Plant Population, Sudden Death Syndrome, and Yield of Soybean. PLANT DISEASE 2016; 100:1735-1743. [PMID: 30686218 DOI: 10.1094/pdis-02-16-0146-re] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A 2-year study was conducted in Illinois, Indiana, Iowa, and Ontario in 2013 and 2014 to determine the effects of planting date, seed treatment, and cultivar on plant population, sudden death syndrome (SDS) caused by Fusarium virguliforme, and grain yield of soybean (Glycine max). Soybean crops were planted from late April to mid-June at approximately 15-day intervals, for a total of three to four plantings per experiment. For each planting date, two cultivars differing in SDS susceptibility were planted with and without fluopyram seed treatment. Mid-May plantings resulted in higher disease index compared with other planting dates in two experiments, early June plantings in three, and the remaining six experiments were not affected by planting date. Soil temperature at planting was not linked to SDS development. Root rot was greater in May plantings for most experiments. Resistant cultivars had significantly lower disease index than the susceptible cultivar in 54.5% of the experiments. Fluopyram reduced disease severity and protected against yield reductions caused by SDS in nearly all plantings and cultivars, with a maximum yield response of 1,142 kg/ha. Plant population was reduced by fluopyram seed treatment and early plantings in some experiments; however, grain yield was not affected by these reductions. Yields of plots planted in mid-June were up to 29.8% less than yields of plots planted in early May. The lack of correlation between early planting date and SDS severity observed in this study indicates that farmers do not have to delay planting in the Midwest to prevent yield loss due to SDS; cultivar selection combined with fluopyram seed treatment can reduce SDS in early-planted soybean (late April to mid May).
Collapse
Affiliation(s)
- Yuba R Kandel
- Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011
| | - Kiersten A Wise
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907
| | - Carl A Bradley
- Department of Crop Sciences, University of Illinois, Urbana 61801
| | - Albert U Tenuta
- Ontario Ministry of Agriculture, Food and Rural Affairs, Ridgetown, ON N0P2C0, Canada
| | - Daren S Mueller
- Department of Plant Pathology and Microbiology, Iowa State University, Ames
| |
Collapse
|
34
|
Yang S, Li X, Chen C, Kyveryga P, Yang XB. Assessing Field-Specific Risk of Soybean Sudden Death Syndrome Using Satellite Imagery in Iowa. PHYTOPATHOLOGY 2016; 106:842-53. [PMID: 27070424 DOI: 10.1094/phyto-11-15-0303-r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Moderate resolution imaging spectroradiometer (MODIS) satellite imagery from 2004 to 2013 were used to assess the field-specific risks of soybean sudden death syndrome (SDS) caused by Fusarium virguliforme in Iowa. Fields with a high frequency of significant decrease (>10%) of the normalized difference vegetation index (NDVI) observed in late July to middle August on historical imagery were hypothetically considered as high SDS risk. These high-risk fields had higher slopes and shorter distances to flowlines, e.g., creeks and drainages, particularly in the Des Moines lobe. Field data in 2014 showed a significantly higher SDS level in the high-risk fields than fields selected without considering NDVI information. On average, low-risk fields had 10 times lower F. virguliforme soil density, determined by quantitative polymerase chain reaction, compared with other surveyed fields. Ordinal logistic regression identified positive correlations between SDS and slope, June NDVI, and May maximum temperature, but high June maximum temperature hindered SDS. A modeled SDS risk map showed a clear trend of potential disease occurrences across Iowa. Landsat imagery was analyzed similarly, to discuss the ability to utilize higher spatial resolution data. The results demonstrated the great potential of both MODIS and Landsat imagery for SDS field-specific risk assessment.
Collapse
Affiliation(s)
- S Yang
- First author: School of Life Sciences, Guizhou Normal University, Guiyang, 550001, China; first, second, third, and fifth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA 50011; and fourth author: Iowa Soybean Association, Ankeny, IA 50023
| | - X Li
- First author: School of Life Sciences, Guizhou Normal University, Guiyang, 550001, China; first, second, third, and fifth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA 50011; and fourth author: Iowa Soybean Association, Ankeny, IA 50023
| | - C Chen
- First author: School of Life Sciences, Guizhou Normal University, Guiyang, 550001, China; first, second, third, and fifth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA 50011; and fourth author: Iowa Soybean Association, Ankeny, IA 50023
| | - P Kyveryga
- First author: School of Life Sciences, Guizhou Normal University, Guiyang, 550001, China; first, second, third, and fifth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA 50011; and fourth author: Iowa Soybean Association, Ankeny, IA 50023
| | - X B Yang
- First author: School of Life Sciences, Guizhou Normal University, Guiyang, 550001, China; first, second, third, and fifth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA 50011; and fourth author: Iowa Soybean Association, Ankeny, IA 50023
| |
Collapse
|
35
|
Kandel YR, Wise KA, Bradley CA, Chilvers MI, Tenuta AU, Mueller DS. Fungicide and Cultivar Effects on Sudden Death Syndrome and Yield of Soybean. PLANT DISEASE 2016; 100:1339-1350. [PMID: 30686207 DOI: 10.1094/pdis-11-15-1263-re] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The effect of fungicides on severity of sudden death syndrome (SDS; caused by Fusarium virguliforme), plant establishment, and soybean yield was evaluated in 12 field experiments conducted in Illinois, Indiana, Iowa, Michigan, and Ontario in 2013 and 2014. Two soybean cultivars that differed in susceptibility to SDS were planted in fields with a history of SDS or with artificial augmentation of F. virguliforme. Efficacy of seed, in-furrow, and foliar-applied fungicides was assessed. SDS levels varied across locations and years. Fluopyram applied on the seed or in-furrow reduced foliar disease index maximum up to 95% in 5 of the 12 experiments. In three experiments with significant (P < 0.10) treatment effect, fluopyram seed treatment improved yields up to 11% compared with the base seed treatment comprising prothioconazole + penflufen + metalaxyl and clothianidin + Bacillus firmus. Meta-analysis also indicated that the fluopyram seed treatment and in-furrow application were effective at reducing SDS and increasing yield relative to the control; however, the baseline disease influenced the yield and disease response to fungicide treatments. Treatment effect was not significant when disease pressure was low. The concentration of F. virguliforme DNA in soybean roots, measured by a specific real-time quantitative polymerase chain reaction assay, was not different among fungicide treatments in 9 of 10 experiments. Moderately resistant cultivars had less disease than susceptible cultivars, indicating that resistant cultivars in combination with fluopyram seed treatment or in-furrow application could provide effective management of SDS.
Collapse
Affiliation(s)
- Yuba R Kandel
- Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011
| | - Kiersten A Wise
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907
| | - Carl A Bradley
- Department of Crop Sciences, University of Illinois, Urbana 61801
| | - Martin I Chilvers
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824
| | - Albert U Tenuta
- Ontario Ministry of Agriculture, Food and Rural Affairs, Ridgetown, ON N0P2C0, Canada
| | - Daren S Mueller
- Department of Plant Pathology and Microbiology, Iowa State University, Ames
| |
Collapse
|
36
|
Swaminathan S, Abeysekara NS, Liu M, Cianzio SR, Bhattacharyya MK. Quantitative trait loci underlying host responses of soybean to Fusarium virguliforme toxins that cause foliar sudden death syndrome. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2016; 129:495-506. [PMID: 26678962 DOI: 10.1007/s00122-015-2643-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 11/21/2015] [Indexed: 06/05/2023]
Abstract
KEY MESSAGE Soybean deploys multiple genetic mechanisms to confer tolerance to Fusarium virguliforme toxins. This study revealed that F. virguliforme culture filtrates could be used in mapping QTL underlying foliar SDS resistance. Sudden death syndrome (SDS) is a major soybean disease throughout most of the soybean growing regions in the world including the United States. The disease is caused by the fungal pathogen, Fusarium virguliforme (Fv). The fungus produces several toxins that are responsible for development of interveinal leaf chlorosis and necrosis, which are typical foliar SDS symptoms. Growing of resistant cultivars has been the most effective method in controlling the disease. The objective of the present study was to identify quantitative trait loci (QTL) underlying host responses of soybean to Fv toxins present in culture filtrates. To accomplish this objective, two recombinant inbred line (RIL) populations, AX19286 (A95-684043 × LS94-3207) and AX19287 (A95-684043 × LS98-0582), segregating for SDS resistance were evaluated for foliar symptom development by applying two screening protocols, the stem cutting and the root feeding assays. The AX19286 population revealed two major and seven minor QTL for SDS resistance. In the AX19287 population, we identified five major QTL and three minor QTL. The two QTL mapped to Chromosome 7 [molecular linkage group (MLG) M] and Chromosome 20 (MLG I) are most likely novel, and were detected through screening of the AX19287 population with stem cutting and root feeding assays, respectively. This study established that Fv culture filtrates could be employed in mapping QTL underlying foliar SDS resistance. The outcomes of the research also suggest that multiple genetic mechanisms might be used by soybean to overcome the toxic effects of the toxins secreted by the pathogen into culture filtrates.
Collapse
Affiliation(s)
| | - Nilwala S Abeysekara
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, 50011, USA
| | - Min Liu
- Visiting Scholar, Department of Agronomy, Iowa State University, Ames, IA, 50011, USA
- Department of Agronomy, Shenyang Agricultural University, 120 Dongling Ave., Shenyang, 110866, Liaoning, China
| | - Silvia R Cianzio
- Department of Agronomy, Iowa State University, Ames, IA, 50011, USA
| | | |
Collapse
|
37
|
Chang HX, Domier LL, Radwan O, Yendrek CR, Hudson ME, Hartman GL. Identification of Multiple Phytotoxins Produced by Fusarium virguliforme Including a Phytotoxic Effector (FvNIS1) Associated With Sudden Death Syndrome Foliar Symptoms. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2016; 29:96-108. [PMID: 26646532 DOI: 10.1094/mpmi-09-15-0219-r] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Sudden death syndrome (SDS) of soybean is caused by a soilborne pathogen, Fusarium virguliforme. Phytotoxins produced by F. virguliforme are translocated from infected roots to leaves, in which they cause SDS foliar symptoms. In this study, additional putative phytotoxins of F. virguliforme were identified, including three secondary metabolites and 11 effectors. While citrinin, fusaric acid, and radicicol induced foliar chlorosis and wilting, Soybean mosaic virus (SMV)-mediated overexpression of F. virguliforme necrosis-inducing secreted protein 1 (FvNIS1) induced SDS foliar symptoms that mimicked the development of foliar symptoms in the field. The expression level of fvnis1 remained steady over time, although foliar symptoms were delayed compared with the expression levels. SMV::FvNIS1 also displayed genotype-specific toxicity to which 75 of 80 soybean cultivars were susceptible. Genome-wide association mapping further identified three single nucleotide polymorphisms at two loci, where three leucine-rich repeat receptor-like protein kinase (LRR-RLK) genes were found. Culture filtrates of fvnis1 knockout mutants displayed a mild reduction in phytotoxicity, indicating that FvNIS1 is one of the phytotoxins responsible for SDS foliar symptoms and may contribute to the quantitative susceptibility of soybean by interacting with the LRR-RLK genes.
Collapse
Affiliation(s)
| | - Leslie L Domier
- 1 University of Illinois
- 2 USDA-Agricultural Research Service; and
| | | | - Craig R Yendrek
- 1 University of Illinois
- 3 Institute for Genomic Biology, Urbana, IL, U.S.A
| | | | - Glen L Hartman
- 1 University of Illinois
- 2 USDA-Agricultural Research Service; and
| |
Collapse
|
38
|
Abeysekara NS, Swaminathan S, Desai N, Guo L, Bhattacharyya MK. The plant immunity inducer pipecolic acid accumulates in the xylem sap and leaves of soybean seedlings following Fusarium virguliforme infection. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2016; 243:105-14. [PMID: 26795155 DOI: 10.1016/j.plantsci.2015.11.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 11/25/2015] [Accepted: 11/26/2015] [Indexed: 06/05/2023]
Abstract
The causal agent of the soybean sudden death syndrome (SDS), Fusarium virguliforme, remains in infected roots and secretes toxins to cause foliar SDS. In this study we investigated the xylem sap, roots, and leaves of F. virguliforme-infected and -uninfected soybean seedlings for any changes in a set of over 3,000 metabolites following pathogen infection by conducting GC/MS and LC/MS/MS, and detected 273 biochemicals. Levels of many intermediates of the TCA cycle were reduced suggesting suppression of this metabolic pathway by the pathogen. There was an increased accumulation of peroxidated lipids in leaves of F. virguliforme-infected plants suggesting possible involvement of free radicals and lipoxygenases in foliar SDS development. Levels of both isoflavone conjugates and isoflavonoid phytoalexins were decreased in infected roots suggesting degradation of these metabolites by the pathogen to promote root necrosis. The levels of the plant immunity inducer pipecolic acid (Pip) and the plant hormone salicylic acid (SA) were significantly increased in xylem sap (in case of Pip) and leaves (in case of both Pip and SA) of F. virguliforme-infected soybean plants compared to the control plants. This suggests a major signaling role of Pip in inducing host defense responses in above ground parts of the F. virguliforme-infected soybean. Increased accumulation of pipecolic acid in foliar tissues was associated with the induction of GmALD1, the soybean homolog of Arabidopsis ALD1. This metabolomics study generated several novel hypotheses for studying the mechanisms of SDS development in soybean.
Collapse
Affiliation(s)
- Nilwala S Abeysekara
- Department of Agronomy, Iowa State University, Ames, IA, USA; Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, USA
| | | | | | | | | |
Collapse
|
39
|
Coleman JJ. The Fusarium solani species complex: ubiquitous pathogens of agricultural importance. MOLECULAR PLANT PATHOLOGY 2016; 17:146-58. [PMID: 26531837 PMCID: PMC6638333 DOI: 10.1111/mpp.12289] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
UNLABELLED Members of the Fusarium solani species complex (FSSC) are capable of causing disease in many agriculturally important crops. The genomes of some of these fungi include supernumerary chromosomes that are dispensable and encode host-specific virulence factors. In addition to genomics, this review summarizes the known molecular mechanisms utilized by members of the FSSC in establishing disease. TAXONOMY Kingdom Fungi; Phylum Ascomycota; Class Sordariomycetes; Order Hypocreales; Family Nectriaceae; Genus Fusarium. HOST RANGE Members of the FSSC collectively have a very broad host range, and have been subdivided previously into formae speciales. Recent phylogenetic analysis has revealed that formae speciales correspond to biologically and phylogenetically distinct species. DISEASE SYMPTOMS Typically, FSSC causes foot and/or root rot of the infected host plant, and the degree of necrosis correlates with the severity of the disease. Symptoms on above-ground portions of the plant can vary greatly depending on the specific FSSC pathogen and host plant, and the disease may manifest as wilting, stunting and chlorosis or lesions on the stem and/or leaves. CONTROL Implementation of agricultural management practices, such as crop rotation and timing of planting, can reduce the risk of crop loss caused by FSSC. If available, the use of resistant varieties is another means to control disease in the field. USEFUL WEBSITES http://genome.jgi-psf.org/Necha2/Necha2.home.html.
Collapse
Affiliation(s)
- Jeffrey J Coleman
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL, 36849, USA
| |
Collapse
|
40
|
Wang B, Swaminathan S, Bhattacharyya MK. Identification of Fusarium virguliforme FvTox1-Interacting Synthetic Peptides for Enhancing Foliar Sudden Death Syndrome Resistance in Soybean. PLoS One 2015; 10:e0145156. [PMID: 26709700 PMCID: PMC4692527 DOI: 10.1371/journal.pone.0145156] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 12/01/2015] [Indexed: 12/01/2022] Open
Abstract
Soybean is one of the most important crops grown across the globe. In the United States, approximately 15% of the soybean yield is suppressed due to various pathogen and pests attack. Sudden death syndrome (SDS) is an emerging fungal disease caused by Fusarium virguliforme. Although growing SDS resistant soybean cultivars has been the main method of controlling this disease, SDS resistance is partial and controlled by a large number of quantitative trait loci (QTL). A proteinacious toxin, FvTox1, produced by the pathogen, causes foliar SDS. Earlier, we demonstrated that expression of an anti-FvTox1 single chain variable fragment antibody resulted in reduced foliar SDS development in transgenic soybean plants. Here, we investigated if synthetic FvTox1-interacting peptides, displayed on M13 phage particles, can be identified for enhancing foliar SDS resistance in soybean. We screened three phage-display peptide libraries and discovered four classes of M13 phage clones displaying FvTox1-interacting peptides. In vitro pull-down assays and in vivo interaction assays in yeast were conducted to confirm the interaction of FvTox1 with these four synthetic peptides and their fusion-combinations. One of these peptides was able to partially neutralize the toxic effect of FvTox1 in vitro. Possible application of the synthetic peptides in engineering SDS resistance soybean cultivars is discussed.
Collapse
Affiliation(s)
- Bing Wang
- Department of Agronomy, Iowa State University, Ames, 50011–1010, United States of America
| | - Sivakumar Swaminathan
- Department of Agronomy, Iowa State University, Ames, 50011–1010, United States of America
| | - Madan K. Bhattacharyya
- Department of Agronomy, Iowa State University, Ames, 50011–1010, United States of America
| |
Collapse
|
41
|
Kandel YR, Haudenshield JS, Srour AY, Islam KT, Fakhoury AM, Santos P, Wang J, Chilvers MI, Hartman GL, Malvick DK, Floyd CM, Mueller DS, Leandro LFS. Multilaboratory Comparison of Quantitative PCR Assays for Detection and Quantification of Fusarium virguliforme from Soybean Roots and Soil. PHYTOPATHOLOGY 2015; 105:1601-11. [PMID: 26368513 DOI: 10.1094/phyto-04-15-0096-r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The ability to accurately detect and quantify Fusarium virguliforme, the cause of sudden death syndrome (SDS) in soybean, in samples such as plant root tissue and soil is extremely valuable for accurate disease diagnoses and to address research questions. Numerous quantitative real-time polymerase chain reaction (qPCR) assays have been developed for this pathogen but their sensitivity and specificity for F. virguliforme have not been compared. In this study, six qPCR assays were compared in five independent laboratories using the same set of DNA samples from fungi, plants, and soil. Multicopy gene-based assays targeting the ribosomal DNA intergenic spacer (IGS) or the mitochondrial small subunit (mtSSU) showed relatively high sensitivity (limit of detection [LOD] = 0.05 to 5 pg) compared with a single-copy gene (FvTox1)-based assay (LOD = 5 to 50 pg). Specificity varied greatly among assays, with the FvTox1 assay ranking the highest (100%) and two IGS assays being slightly less specific (95 to 96%). Another IGS assay targeting four SDS-causing fusaria showed lower specificity (70%), while the two mtSSU assays were lowest (41 and 47%). An IGS-based assay showed consistently highest sensitivity (LOD = 0.05 pg) and specificity and inclusivity above 94% and, thus, is suggested as the most useful qPCR assay for F. virguliforme diagnosis and quantification. However, specificity was also above 94% in two other assays and their selection for diagnostics and research will depend on objectives, samples, and materials used. These results will facilitate both fundamental and disease management research pertinent to SDS.
Collapse
Affiliation(s)
- Yuba R Kandel
- First, twelfth, and thirteenth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; second and ninth authors: United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801; third, fourth, and fifth authors: Department of Plant, Soil and Ag. Systems, Southern Illinois University, Carbondale 62901; sixth author: Department of Biochemistry and Molecular Biology, UNR 1664, N. Virginia St. MS 330, Reno, NV; seventh, and eighth authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824; and tenth and eleventh authors: Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - James S Haudenshield
- First, twelfth, and thirteenth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; second and ninth authors: United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801; third, fourth, and fifth authors: Department of Plant, Soil and Ag. Systems, Southern Illinois University, Carbondale 62901; sixth author: Department of Biochemistry and Molecular Biology, UNR 1664, N. Virginia St. MS 330, Reno, NV; seventh, and eighth authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824; and tenth and eleventh authors: Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - Ali Y Srour
- First, twelfth, and thirteenth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; second and ninth authors: United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801; third, fourth, and fifth authors: Department of Plant, Soil and Ag. Systems, Southern Illinois University, Carbondale 62901; sixth author: Department of Biochemistry and Molecular Biology, UNR 1664, N. Virginia St. MS 330, Reno, NV; seventh, and eighth authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824; and tenth and eleventh authors: Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - Kazi Tariqul Islam
- First, twelfth, and thirteenth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; second and ninth authors: United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801; third, fourth, and fifth authors: Department of Plant, Soil and Ag. Systems, Southern Illinois University, Carbondale 62901; sixth author: Department of Biochemistry and Molecular Biology, UNR 1664, N. Virginia St. MS 330, Reno, NV; seventh, and eighth authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824; and tenth and eleventh authors: Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - Ahmad M Fakhoury
- First, twelfth, and thirteenth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; second and ninth authors: United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801; third, fourth, and fifth authors: Department of Plant, Soil and Ag. Systems, Southern Illinois University, Carbondale 62901; sixth author: Department of Biochemistry and Molecular Biology, UNR 1664, N. Virginia St. MS 330, Reno, NV; seventh, and eighth authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824; and tenth and eleventh authors: Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - Patricia Santos
- First, twelfth, and thirteenth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; second and ninth authors: United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801; third, fourth, and fifth authors: Department of Plant, Soil and Ag. Systems, Southern Illinois University, Carbondale 62901; sixth author: Department of Biochemistry and Molecular Biology, UNR 1664, N. Virginia St. MS 330, Reno, NV; seventh, and eighth authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824; and tenth and eleventh authors: Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - Jie Wang
- First, twelfth, and thirteenth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; second and ninth authors: United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801; third, fourth, and fifth authors: Department of Plant, Soil and Ag. Systems, Southern Illinois University, Carbondale 62901; sixth author: Department of Biochemistry and Molecular Biology, UNR 1664, N. Virginia St. MS 330, Reno, NV; seventh, and eighth authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824; and tenth and eleventh authors: Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - Martin I Chilvers
- First, twelfth, and thirteenth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; second and ninth authors: United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801; third, fourth, and fifth authors: Department of Plant, Soil and Ag. Systems, Southern Illinois University, Carbondale 62901; sixth author: Department of Biochemistry and Molecular Biology, UNR 1664, N. Virginia St. MS 330, Reno, NV; seventh, and eighth authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824; and tenth and eleventh authors: Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - Glen L Hartman
- First, twelfth, and thirteenth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; second and ninth authors: United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801; third, fourth, and fifth authors: Department of Plant, Soil and Ag. Systems, Southern Illinois University, Carbondale 62901; sixth author: Department of Biochemistry and Molecular Biology, UNR 1664, N. Virginia St. MS 330, Reno, NV; seventh, and eighth authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824; and tenth and eleventh authors: Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - Dean K Malvick
- First, twelfth, and thirteenth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; second and ninth authors: United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801; third, fourth, and fifth authors: Department of Plant, Soil and Ag. Systems, Southern Illinois University, Carbondale 62901; sixth author: Department of Biochemistry and Molecular Biology, UNR 1664, N. Virginia St. MS 330, Reno, NV; seventh, and eighth authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824; and tenth and eleventh authors: Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - Crystal M Floyd
- First, twelfth, and thirteenth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; second and ninth authors: United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801; third, fourth, and fifth authors: Department of Plant, Soil and Ag. Systems, Southern Illinois University, Carbondale 62901; sixth author: Department of Biochemistry and Molecular Biology, UNR 1664, N. Virginia St. MS 330, Reno, NV; seventh, and eighth authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824; and tenth and eleventh authors: Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - Daren S Mueller
- First, twelfth, and thirteenth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; second and ninth authors: United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801; third, fourth, and fifth authors: Department of Plant, Soil and Ag. Systems, Southern Illinois University, Carbondale 62901; sixth author: Department of Biochemistry and Molecular Biology, UNR 1664, N. Virginia St. MS 330, Reno, NV; seventh, and eighth authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824; and tenth and eleventh authors: Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - Leonor F S Leandro
- First, twelfth, and thirteenth authors: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; second and ninth authors: United States Department of Agriculture-Agricultural Research Service, Urbana, IL 61801; third, fourth, and fifth authors: Department of Plant, Soil and Ag. Systems, Southern Illinois University, Carbondale 62901; sixth author: Department of Biochemistry and Molecular Biology, UNR 1664, N. Virginia St. MS 330, Reno, NV; seventh, and eighth authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824; and tenth and eleventh authors: Department of Plant Pathology, University of Minnesota, St. Paul 55108
| |
Collapse
|
42
|
Bao Y, Kurle JE, Anderson G, Young ND. Association mapping and genomic prediction for resistance to sudden death syndrome in early maturing soybean germplasm. MOLECULAR BREEDING : NEW STRATEGIES IN PLANT IMPROVEMENT 2015; 35:128. [PMID: 25999779 PMCID: PMC4434860 DOI: 10.1007/s11032-015-0324-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Accepted: 05/08/2015] [Indexed: 05/05/2023]
Abstract
Sudden death syndrome (SDS), caused by Fusarium virguliforme, has spread to northern soybean growing regions in the US causing significant yield losses. The objectives of this study were to identify loci underlying variation in plant responses to SDS through association mapping (AM) and to assess prediction accuracy of genomic selection (GS) in a panel of early maturing soybean germplasm. A set of 282 soybean breeding lines was selected from the University of Minnesota soybean breeding program and then genotyped using a genome-wide panel of 1536 single-nucleotide polymorphism markers. Four resistance traits, root lesion severity (RLS), foliar symptom severity (FSS), root retention (RR), and dry matter reduction (DMR), were evaluated using soil inoculation in the greenhouse. AM identified significant peaks in genomic regions of known SDS resistance quantitative trait loci cqSDS001, cqRfs4, and SDS11-2. Additionally, two novel loci, one on chromosome 3 and another on chromosome 18, were tentatively identified. A ninefold cross-validation scheme was used to assess the prediction accuracy of GS for SDS resistance. The prediction accuracy of single-trait GS (ST-GS) was 0.64 for RLS, but less than 0.30 for RR, DMR, and FSS. Compared to ST-GS, none of multi-trait GS (MT-GS) models significantly improved the prediction accuracy due to weak correlations between the four traits. This study suggests both AM and GS hold promise for implementation in genetic improvement of SDS resistance in existing soybean breeding programs.
Collapse
Affiliation(s)
- Yong Bao
- />Department of Agronomy and Plant Genetics, University of Minnesota, 411 Borlaug Hall, St. Paul, MN 55108-6026 USA
| | - James E. Kurle
- />Department of Plant Pathology, University of Minnesota, 495 Borlaug Hall, St. Paul, MN 55108 USA
| | - Grace Anderson
- />Department of Plant Pathology, University of Minnesota, 495 Borlaug Hall, St. Paul, MN 55108 USA
| | - Nevin D. Young
- />Department of Plant Pathology, University of Minnesota, 495 Borlaug Hall, St. Paul, MN 55108 USA
| |
Collapse
|
43
|
Xiang Y, Scandiani MM, Herman TK, Hartman GL. Optimizing Conditions of a Cell-Free Toxic Filtrate Stem Cutting Assay to Evaluate Soybean Genotype Responses to Fusarium Species that Cause Sudden Death Syndrome. PLANT DISEASE 2015; 99:502-507. [PMID: 30699546 DOI: 10.1094/pdis-08-14-0791-re] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Cell-free toxic culture filtrates from Fusarium virguliforme, the causal fungus of soybean sudden death syndrome (SDS), cause foliar symptoms on soybean stem cuttings similar to those obtained from root inoculations in whole plants and those observed in production fields. The objectives of this study were to (i) optimize the production conditions for F. virguliforme cell-free toxic culture filtrates and the incubation conditions of the stem cutting assay used to test the toxicity of the cell-free toxic culture filtrates, and (ii) use the optimized assay and a whole plant root inoculation assay to compare four SDS-causing isolates on a panel of selected soybean genotypes. Area under the disease progress curve (AUDPC) values were highest (P = 0.05) when cuttings were immersed in culture filtrate of fungus grown in soybean dextrose broth, in filtrate produced from the fungus grown for 18 or 22 days, and when stem cuttings were incubated at 30°C. AUDPC values and shoot dry weights from the whole plant root inoculations and the AUDPC values from the stem cutting assay differed (P < 0.05) among nine soybean genotypes tested with F. virguliforme and F. tucumaniae isolates, and the AUDPC values from the two assays were positively correlated (r = 0.44 at P < 0.0001).
Collapse
Affiliation(s)
- Y Xiang
- Department of Crop Sciences, University of Illinois, Urbana 61801
| | - M M Scandiani
- Centro de Referencia de Micología, Fac. de Cs Bioq. y Farm. UNR, Suipacha 531, Rosario, Argentina
| | - T K Herman
- Department of Crop Sciences, University of Illinois, Urbana 61801
| | - G L Hartman
- USDA-Agricultural Research Services and Department of Crop Sciences, University of Illinois, Urbana 61801
| |
Collapse
|
44
|
|
45
|
Abeysekara NS, Bhattacharyya MK. Analyses of the xylem sap proteomes identified candidate Fusarium virguliforme proteinacious toxins. PLoS One 2014; 9:e93667. [PMID: 24845418 PMCID: PMC4028188 DOI: 10.1371/journal.pone.0093667] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Accepted: 03/09/2014] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Sudden death syndrome (SDS) caused by the ascomycete fungus, Fusarium virguliforme, exhibits root necrosis and leaf scorch or foliar SDS. The pathogen has never been identified from the above ground diseased foliar tissues. Foliar SDS is believed to be caused by host selective toxins, including FvTox1, secreted by the fungus. This study investigated if the xylem sap of F. virguliforme-infected soybean plants contains secreted F. virguliforme-proteins, some of which could cause foliar SDS development. RESULTS Xylem sap samples were collected from five biological replications of F. virguliforme-infected and uninfected soybean plants under controlled conditions. We identified five F. virguliforme proteins from the xylem sap of the F. virguliforme-infected soybean plants by conducting LC-ESI-MS/MS analysis. These five proteins were also present in the excreted proteome of the pathogen in culture filtrates. One of these proteins showed high sequence identity to cerato-platanin, a phytotoxin produced by Ceratocystis fimbriata f. sp. platani to cause canker stain disease in the plane tree. Of over 500 soybean proteins identified in this study, 112 were present in at least 80% of the sap samples collected from F. virguliforme-infected and -uninfected control plants. We have identified four soybean defense proteins from the xylem sap of F. virguliforme-infected soybean plants. The data have been deposited to the ProteomeXchange with identifier PXD000873. CONCLUSION This study confirms that a few F. virguliforme proteins travel through the xylem, some of which could be involved in foliar SDS development. We have identified five candidate proteinaceous toxins, one of which showed high similarity to a previously characterized phytotoxin. We have also shown the presence of four soybean defense proteins in the xylem sap of F. virguliforme-infected soybean plants. This study laid the foundation for studying the molecular basis of foliar SDS development in soybean and possible defense mechanisms that may be involved in conferring immunity against F. virguliforme and other soybean pathogens.
Collapse
Affiliation(s)
- Nilwala S. Abeysekara
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, Iowa, United States of America
- Department of Agronomy, Iowa State University, Ames, Iowa, United States of America
| | | |
Collapse
|
46
|
Srivastava SK, Huang X, Brar HK, Fakhoury AM, Bluhm BH, Bhattacharyya MK. The genome sequence of the fungal pathogen Fusarium virguliforme that causes sudden death syndrome in soybean. PLoS One 2014; 9:e81832. [PMID: 24454689 PMCID: PMC3891557 DOI: 10.1371/journal.pone.0081832] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Accepted: 10/28/2013] [Indexed: 02/02/2023] Open
Abstract
UNLABELLED Fusarium virguliforme causes sudden death syndrome (SDS) of soybean, a disease of serious concern throughout most of the soybean producing regions of the world. Despite the global importance, little is known about the pathogenesis mechanisms of F. virguliforme. Thus, we applied Next-Generation DNA Sequencing to reveal the draft F. virguliforme genome sequence and identified putative pathogenicity genes to facilitate discovering the mechanisms used by the pathogen to cause this disease. METHODOLOGY/PRINCIPAL FINDINGS We have generated the draft genome sequence of F. virguliforme by conducting whole-genome shotgun sequencing on a 454 GS-FLX Titanium sequencer. Initially, single-end reads of a 400-bp shotgun library were assembled using the PCAP program. Paired end sequences from 3 and 20 Kb DNA fragments and approximately 100 Kb inserts of 1,400 BAC clones were used to generate the assembled genome. The assembled genome sequence was 51 Mb. The N50 scaffold number was 11 with an N50 Scaffold length of 1,263 Kb. The AUGUSTUS gene prediction program predicted 14,845 putative genes, which were annotated with Pfam and GO databases. Gene distributions were uniform in all but one of the major scaffolds. Phylogenic analyses revealed that F. virguliforme was closely related to the pea pathogen, Nectria haematococca. Of the 14,845 F. virguliforme genes, 11,043 were conserved among five Fusarium species: F. virguliforme, F. graminearum, F. verticillioides, F. oxysporum and N. haematococca; and 1,332 F. virguliforme-specific genes, which may include pathogenicity genes. Additionally, searches for candidate F. virguliforme pathogenicity genes using gene sequences of the pathogen-host interaction database identified 358 genes. CONCLUSIONS The F. virguliforme genome sequence and putative pathogenicity genes presented here will facilitate identification of pathogenicity mechanisms involved in SDS development. Together, these resources will expedite our efforts towards discovering pathogenicity mechanisms in F. virguliforme. This will ultimately lead to improvement of SDS resistance in soybean.
Collapse
Affiliation(s)
- Subodh K. Srivastava
- Department of Agronomy, Iowa State University, Ames, Iowa, United States of America
| | - Xiaoqiu Huang
- Department of Computer Science, Iowa State University, Ames, Iowa, United States of America
| | - Hargeet K. Brar
- Department of Agronomy, Iowa State University, Ames, Iowa, United States of America
| | - Ahmad M. Fakhoury
- Department of Plant, Soil Science, and Agricultural Systems, Southern Illinois University, Carbondale, Illinois, United States of America
| | - Burton H. Bluhm
- Department of Plant Pathology, University of Arkansas, Fayetteville, Arkansas, United States of America
| | | |
Collapse
|
47
|
Pudake RN, Swaminathan S, Sahu BB, Leandro LF, Bhattacharyya MK. Investigation of the Fusarium virguliforme fvtox1 mutants revealed that the FvTox1 toxin is involved in foliar sudden death syndrome development in soybean. Curr Genet 2013; 59:107-17. [PMID: 23702608 DOI: 10.1007/s00294-013-0392-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 04/03/2013] [Accepted: 04/16/2013] [Indexed: 12/13/2022]
Abstract
The soil borne fungus, Fusarium virguliforme, causes sudden death syndrome (SDS) in soybean, which is a serious foliar and root rot disease. The pathogen has never been isolated from the diseased foliar tissues; phytotoxins produced by the pathogen are believed to cause foliar SDS symptoms. One of these toxins, a 13.5-kDa acidic protein named FvTox1, has been hypothesized to interfere with photosynthesis in infected soybean plants and cause foliar SDS. The objective of this study is to determine if FvTox1 is involved in foliar SDS development. We created and studied five independent knockout fvtox1 mutants to study the function of FvTox1. We conducted Agrobacterium tumefaciens-mediated transformation to accomplish homologous recombination of FvTox1 with a hygromycin B resistance gene, hph, to generate the fvtox1 mutants. Approximately 40 hygromycin-resistant transformants were obtained from 10(6) conidial spores of the F. virguliforme Mont-1 isolate when the spores were co-cultivated with the A. tumefaciens EHA105 but not with LBA4044 strain carrying a recombinant binary plasmid, in which the hph gene encoding hygromycin resistance was flanked by 5'- and 3'-end FvTox1 sequences. We observed homologous recombination-mediated integration of hph into the FvTox1 locus among five independent fvtox1 mutants. In stem-cutting assays using cut soybean seedlings fed with cell-free F. virguliforme culture filtrates, the knockout fvtox1 mutants caused chlorophyll losses and foliar SDS symptoms, which were over twofold less than those caused by the virulent F. virguliforme Mont-1 isolate. Similarly, in root inoculation assays, more than a twofold reduction in foliar SDS development and chlorophyll losses was observed among the seedlings infected with the fvtox1 mutants as compared to the seedlings infected with the wild-type Mont-1 isolate. These results suggest that FvTox1 is a major virulence factor involved in foliar SDS development in soybean. It is expected that interference of the function of this toxin in transgenic soybean plants will lead to generation of SDS-resistant soybean cultivars.
Collapse
Affiliation(s)
- Ramesh N Pudake
- Department of Agronomy, Iowa State University, Ames, IA 50011-1010, USA
| | | | | | | | | |
Collapse
|
48
|
Radwan O, Li M, Calla B, Li S, Hartman GL, Clough SJ. Effect of Fusarium virguliforme phytotoxin on soybean gene expression suggests a role in multidimensional defence. MOLECULAR PLANT PATHOLOGY 2013; 14:293-307. [PMID: 23240728 PMCID: PMC6638634 DOI: 10.1111/mpp.12006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Sudden death syndrome (SDS), caused by Fusarium virguliforme, is an important yield-limiting disease of soybean. This soil-borne fungus colonizes soybean roots causing root rot, and also releases a phytotoxin that is translocated to leaves causing interveinal chlorosis and necrosis leading to defoliation and early maturation. The objective of our study was to compare gene expression profiles during the early response of soybean leaves exposed to sterile culture filtrates of F. virguliforme in soybean genotypes with different levels of resistance to SDS. The analysis identified SDS-related defence genes that were induced in the most resistant genotype, but not in the other genotypes. Further functional annotations based on sequence homology suggested that some of the induced genes probably encode proteins involved in cell wall modification, detoxification, defence responses, primary metabolism and membrane transport. Quantitative real-time reverse-transcribed polymerase chain reaction confirmed the differential transcript accumulation of a subset of these genes. In addition, in silico mapping of differentially expressed genes to SDS-resistant quantitative trait loci allowed for the identification of new potential defence genes that could be genetically mapped to the soybean genome, and could be used further in a marker-assisted selection programme. A comparison of the response of soybean to F. virguliforme phytotoxin (Fv toxin) relative to other biotic and abiotic stresses revealed that the resistance response to Fv toxin is quite similar to the response to inoculation with an incompatible Pseudomonas syringae pv. glycinea strain, suggesting that Fv toxin might induce hypersensitive response pathways in soybean leaf tissues in the absence of pathogen in these tissues.
Collapse
Affiliation(s)
- Osman Radwan
- Department of Crop Sciences, University of Illinois, Urbana, IL 61801, USA
| | | | | | | | | | | |
Collapse
|
49
|
Srour A, Afzal AJ, Blahut-Beatty L, Hemmati N, Simmonds DH, Li W, Liu M, Town CD, Sharma H, Arelli P, Lightfoot DA. The receptor like kinase at Rhg1-a/Rfs2 caused pleiotropic resistance to sudden death syndrome and soybean cyst nematode as a transgene by altering signaling responses. BMC Genomics 2012; 13:368. [PMID: 22857610 PMCID: PMC3439264 DOI: 10.1186/1471-2164-13-368] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Accepted: 06/12/2012] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Soybean (Glycine max (L. Merr.)) resistance to any population of Heterodera glycines (I.), or Fusarium virguliforme (Akoi, O'Donnell, Homma & Lattanzi) required a functional allele at Rhg1/Rfs2. H. glycines, the soybean cyst nematode (SCN) was an ancient, endemic, pest of soybean whereas F. virguliforme causal agent of sudden death syndrome (SDS), was a recent, regional, pest. This study examined the role of a receptor like kinase (RLK) GmRLK18-1 (gene model Glyma_18_02680 at 1,071 kbp on chromosome 18 of the genome sequence) within the Rhg1/Rfs2 locus in causing resistance to SCN and SDS. RESULTS A BAC (B73p06) encompassing the Rhg1/Rfs2 locus was sequenced from a resistant cultivar and compared to the sequences of two susceptible cultivars from which 800 SNPs were found. Sequence alignments inferred that the resistance allele was an introgressed region of about 59 kbp at the center of which the GmRLK18-1 was the most polymorphic gene and encoded protein. Analyses were made of plants that were either heterozygous at, or transgenic (and so hemizygous at a new location) with, the resistance allele of GmRLK18-1. Those plants infested with either H. glycines or F. virguliforme showed that the allele for resistance was dominant. In the absence of Rhg4 the GmRLK18-1 was sufficient to confer nearly complete resistance to both root and leaf symptoms of SDS caused by F. virguliforme and provided partial resistance to three different populations of nematodes (mature female cysts were reduced by 30-50%). In the presence of Rhg4 the plants with the transgene were nearly classed as fully resistant to SCN (females reduced to 11% of the susceptible control) as well as SDS. A reduction in the rate of early seedling root development was also shown to be caused by the resistance allele of the GmRLK18-1. Field trials of transgenic plants showed an increase in foliar susceptibility to insect herbivory. CONCLUSIONS The inference that soybean has adapted part of an existing pathogen recognition and defense cascade (H.glycines; SCN and insect herbivory) to a new pathogen (F. virguliforme; SDS) has broad implications for crop improvement. Stable resistance to many pathogens might be achieved by manipulation the genes encoding a small number of pathogen recognition proteins.
Collapse
Affiliation(s)
- Ali Srour
- Department of Molecular Biology, Microbiology and Biochemistry, Southern Illinois University at Carbondale, Carbondale, IL 62901, USA
- Department of Plant Soil and Agricultural Systems, Southern Illinois University at Carbondale, Carbondale, IL 62901-4415, USA
| | - Ahmed J Afzal
- Department of Molecular Biology, Microbiology and Biochemistry, Southern Illinois University at Carbondale, Carbondale, IL 62901, USA
- Department of Plant Soil and Agricultural Systems, Southern Illinois University at Carbondale, Carbondale, IL 62901-4415, USA
- Department of Horticulture and Crop Science, Ohio State University, 2021 Coffey Rd, Columbus, OH 43210, USA
| | - Laureen Blahut-Beatty
- Agriculture and Agri-Food Canada, Building 21, 960 Carling Ave, Ottawa, ON K1A 0C6, USA
| | - Naghmeh Hemmati
- Department of Molecular Biology, Microbiology and Biochemistry, Southern Illinois University at Carbondale, Carbondale, IL 62901, USA
| | - Daina H Simmonds
- Agriculture and Agri-Food Canada, Building 21, 960 Carling Ave, Ottawa, ON K1A 0C6, USA
| | - Wenbin Li
- Key Laboratory of Soybean Biology in the Chinese Ministry of Education, Harbin University, Harbin, China
| | - Miao Liu
- Key Laboratory of Soybean Biology in the Chinese Ministry of Education, Harbin University, Harbin, China
| | | | - Hemlata Sharma
- Department of Molecular Biology, Microbiology and Biochemistry, Southern Illinois University at Carbondale, Carbondale, IL 62901, USA
- Department of Plant Breeding & Genetics, Rajasthan College of Agriculture, MPUAT, Udaipur, India
| | | | - David A Lightfoot
- Department of Molecular Biology, Microbiology and Biochemistry, Southern Illinois University at Carbondale, Carbondale, IL 62901, USA
- Department of Plant Soil and Agricultural Systems, Southern Illinois University at Carbondale, Carbondale, IL 62901-4415, USA
- Key Laboratory of Soybean Biology in the Chinese Ministry of Education, Harbin University, Harbin, China
- Genomics Core Facility; Center for Excellence the Illinois Soybean Center, Southern Illinois University at Carbondale, Carbondale, IL 62901-4415, USA
| |
Collapse
|
50
|
Brar HK, Bhattacharyya MK. Expression of a single-chain variable-fragment antibody against a Fusarium virguliforme toxin peptide enhances tolerance to sudden death syndrome in transgenic soybean plants. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2012; 25:817-24. [PMID: 22397408 DOI: 10.1094/mpmi-12-11-0317] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Plants do not produce antibodies. However, plants can correctly assemble functional antibody molecules encoded by mammalian antibody genes. Many plant diseases are caused by pathogen toxins. One such disease is the soybean sudden death syndrome (SDS). SDS is a serious disease caused by the fungal pathogen Fusarium virguliforme. The pathogen, however, has never been isolated from diseased foliar tissues. Thus, one or more toxins produced by the pathogen have been considered to cause foliar SDS. One of these possible toxins, FvTox1, was recently identified. We investigated whether expression of anti-FvTox1 single-chain variable-fragment (scFv) antibody in transgenic soybean can confer resistance to foliar SDS. We have created two scFv antibody genes, Anti-FvTox1-1 and Anti-FvTox1-2, encoding anti-FvTox1 scFv antibodies from RNAs of a hybridoma cell line that expresses mouse monoclonal anti-FvTox1 7E8 antibody. Both anti-FvTox1 scFv antibodies interacted with an antigenic site of FvTox1 that binds to mouse monoclonal anti-FvTox1 7E8 antibody. Binding of FvTox1 by the anti-FvTox1 scFv antibodies, expressed in either Escherichia coli or transgenic soybean roots, was initially verified on nitrocellulose membranes. Expression of anti-FvTox1-1 in stable transgenic soybean plants resulted in enhanced foliar SDS resistance compared with that in nontransgenic control plants. Our results suggest that i) FvTox1 is an important pathogenicity factor for foliar SDS development and ii) expression of scFv antibodies against pathogen toxins could be a suitable biotechnology approach for protecting crop plants from toxin-induced diseases.
Collapse
Affiliation(s)
- Hargeet K Brar
- Department of Agronomy and Interdepartmental Genetics Graduate Major Program, Iowa State University, Ames, IA 50011-1010, USA
| | | |
Collapse
|