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Martínez M, Arata A, Dinolfo MI, Lázaro L, Welin B, Stenglein S. Evaluation of PSP1 biostimulant on Fusarium graminearum-wheat pathosystem: impact on disease parameters, grain yield, and grain quality. PEST MANAGEMENT SCIENCE 2024; 80:3578-3589. [PMID: 38450978 DOI: 10.1002/ps.8062] [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: 08/16/2023] [Revised: 02/20/2024] [Accepted: 03/07/2024] [Indexed: 03/08/2024]
Abstract
BACKGROUND Plant defense elicitors are valuable tools in sustainable agriculture, providing an environmentally friendly and effective means of enhancing plant defense and promoting plant health. Fusarium head blight (FHB) is one of the most important fungal diseases of cereal crops worldwide. The PSP1 is a novel biopesticide formulated based on an elicitor, the extracellular protein AsES, from the fungus Sarocladium strictum. The present work aimed to evaluate the effectiveness of PSP1 in controlling FHB under field conditions. Experiments were conducted during three consecutive growing seasons (2019, 2020, and 2021). Three biostimulant treatments were tested in different physiological stages (from late tillering to heading stage), and FHB inoculations were performed at anthesis. Disease parameters, seed parameters, grain yield, and grain quality parameters were evaluated. RESULTS Depending on the year and the genotype, reductions in disease incidence (up to 11%) and disease severity (up to 5%) were reported, although these differences could not be attributed to the use of the PSP1 biostimulant. Occasional improvements in seed parameters and grain quality were observed, suggesting that early treatments could work better than late treatments, probably due to early activation/priming of defense response mechanisms. However, more studies are deemed necessary. CONCLUSION The use of PSP1 biostimulant in commercial wheat crops could be a biological alternative or complement to traditional chemical fungicides to manage FHB. The reduced environmental impact and the potential benefits in grain yield and quality are other reasons that can generate new adherents of this technology in worldwide agriculture systems in the coming years. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Mauro Martínez
- Laboratorio de Biología Funcional y Biotecnología, BIOLAB-INBIOTEC-CONICET-CICBA. Facultad de Agronomía, UNCPBA, Buenos Aires, Argentina
- Área de Mejoramiento y Genética Vegetal. Facultad de Agronomía, UNCPBA, Buenos Aires, Argentina
| | - Agustín Arata
- Laboratorio de Biología Funcional y Biotecnología, BIOLAB-INBIOTEC-CONICET-CICBA. Facultad de Agronomía, UNCPBA, Buenos Aires, Argentina
- Centro de Investigaciones Integradas sobre Sistemas Agronómicos Sustentables (CIISAS). Facultad de Agronomía, UNCPBA, Buenos Aires, Argentina
| | - María Inés Dinolfo
- Laboratorio de Biología Funcional y Biotecnología, BIOLAB-INBIOTEC-CONICET-CICBA. Facultad de Agronomía, UNCPBA, Buenos Aires, Argentina
- Área de Mejoramiento y Genética Vegetal. Facultad de Agronomía, UNCPBA, Buenos Aires, Argentina
| | - Laura Lázaro
- Centro de Investigaciones Integradas sobre Sistemas Agronómicos Sustentables (CIISAS). Facultad de Agronomía, UNCPBA, Buenos Aires, Argentina
| | - Björn Welin
- Instituto de Tecnología Agroindustrial del Noroeste Argentino, Estación Experimental Agroindustrial Obispo Colombres-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Tucumán, Argentina
| | - Sebastián Stenglein
- Laboratorio de Biología Funcional y Biotecnología, BIOLAB-INBIOTEC-CONICET-CICBA. Facultad de Agronomía, UNCPBA, Buenos Aires, Argentina
- Área de Microbiología. Facultad de Agronomía, UNCPBA, Buenos Aires, Argentina
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Moraes WB, Madden LV, Paul PA. Efficacy of Genetic Resistance and Fungicide Application Against Fusarium Head Blight and Mycotoxins in Wheat Under Persistent Pre- and Postanthesis Moisture. PLANT DISEASE 2022; 106:2839-2855. [PMID: 35471074 DOI: 10.1094/pdis-02-22-0263-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
Field experiments were conducted to investigate the efficacy of fungicide treatments in combination with genetic resistance against Fusarium head blight (FHB) and its associated mycotoxins under persistently wet pre- and postanthesis conditions in plots inoculated with Fusarium graminearum-colonized corn spawn. Treatments consisted of a single application of prothioconazole + tebuconazole at early anthesis (PA), or at 3 (P3), 6 (P6), or 9 (P9) days after early anthesis, or PA followed by a single application of metconazole at 3 (PA+C3), 6 (PA+C6), or 9 (PA+C9) days after early anthesis. PA and P3 were the most efficacious of the single-application treatments in terms of mean percentage control of FHB index (IND), deoxynivalenol (DON), zearalenone (ZEA), and mean increase in grain yield and test weight (TW) relative to the nontreated susceptible check (S_CK). The double-application treatments (PA+C3, PA+C6, and PA+C9) were the most effective of all tested fungicide programs. However, relative to S_CK, the highest overall mean percentage reduction in IND, DON, and ZEA and increase in grain yield and TW were observed when the double-application fungicide programs were integrated with genetic resistance. The estimated net cash income (NCI) of the integrated management (IM) programs was consistently higher than the NCI of other tested programs across different grain prices and fungicide application costs. Thus, the benefits of the two-treatment IM programs under highly favorable conditions for FHB development were enough to offset the cost of two applications, making these programs profitable.
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Affiliation(s)
- Wanderson Bucker Moraes
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
| | - Laurence V Madden
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
| | - Pierce A Paul
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
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Rebouh NY, Aliat T, Polityko PM, Kherchouche D, Boulelouah N, Temirbekova SK, Afanasyeva YV, Kucher DE, Plushikov VG, Parakhina EA, Latati M, Gadzhikurbanov AS. Environmentally Friendly Wheat Farming: Biological and Economic Efficiency of Three Treatments to Control Fungal Diseases in Winter Wheat ( Triticum aestivum L.) under Field Conditions. PLANTS (BASEL, SWITZERLAND) 2022; 11:1566. [PMID: 35736716 PMCID: PMC9228977 DOI: 10.3390/plants11121566] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/07/2022] [Accepted: 06/10/2022] [Indexed: 01/13/2023]
Abstract
The control of wheat diseases using bioagents is not well studied under field conditions. The present study was aimed at investigating, during four consecutive growing seasons (2017-2020), the efficacy of two integrated crop protection (ICP) systems to control the common wheat diseases for enhancing the productivity and profitability of winter wheat crops and ensuring nutritional and food security. Two environmental-friendly treatments were tested, biological (T1), which contained bioagents and fertilizers, and combined (T2), which included fertilizers and bioagents coupled with lower doses of fungicides. The chemical treatment (T3) was used for comparison with (T1) and (T2). Furthermore, two Russian winter wheat varieties (Nemchinovskaya 17 (V1) and Moscovskaya 40 (V2)) were studied. A randomized complete block design was used with four replicates. Diseases infestation rates for snow mold (SM), root rot (RR), powdery mildew (PM), and Fusarium (Fus), yield performances, and grain quality (measured through protein content) were determined according to the tested treatments, and the economic efficiency was calculated for each treatment. The combined treatment (T2) was the most effective against fungal diseases with 1.8% (SM), 1.2% (RR), 0.9% (PM), and 0.9% (Fus). The highest grain yield (6.8 t·ha-1), protein content (15.2%), and 1000-grain weight (43.7%) were observed for winter wheat variety Moscovskaya 40 with the combined treatment (T2). The highest number of productive stems (N.P.S) (556 stems/m2) was attained for combined treatment (T2), followed by biological treatment (T1) (552 stems/m2) with the variety Nemchinovskaya 17. The profitability (cost-benefit ratio) of the combined treatment (T2) was 2.38 with the Moscovskaya 40 variety (V2), while 2.03 was recorded for the biological treatment. Applying environmentally friendly combined and biological treatments resulted in high wheat yield and net income, as well as healthy products.
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Affiliation(s)
- Nazih Y. Rebouh
- Department of Environmental Management, Peoples’ Friendship University of Russia (RUDN University), 117198 Moscow, Russia; (D.E.K.); (V.G.P.); (E.A.P.); (M.L.)
| | - Toufik Aliat
- Forest Management Department, Higher National School of Forests, Khenchela 40000, Algeria;
| | - Petr M. Polityko
- GNU Moscow Research Institute of Agriculture “Nemchinovka”, 143026 Moscow, Russia;
| | - Dalila Kherchouche
- Department of Agronomy, Institute of Veterinary and Agronomy Sciences, University Batna 1, Batna 05000, Algeria; (D.K.); (N.B.)
| | - Nadia Boulelouah
- Department of Agronomy, Institute of Veterinary and Agronomy Sciences, University Batna 1, Batna 05000, Algeria; (D.K.); (N.B.)
| | - Sulukhan K. Temirbekova
- All-Russian Research Institute of Phytopathology, Bolshye Vyazyomy, Odintsovo District, 143050 Moscow, Russia;
| | - Yuliya V. Afanasyeva
- Federal Horticultural Center for Breeding, Agrotechnology and Nursery, 115598 Moscow, Russia;
| | - Dmitry E. Kucher
- Department of Environmental Management, Peoples’ Friendship University of Russia (RUDN University), 117198 Moscow, Russia; (D.E.K.); (V.G.P.); (E.A.P.); (M.L.)
| | - Vadim G. Plushikov
- Department of Environmental Management, Peoples’ Friendship University of Russia (RUDN University), 117198 Moscow, Russia; (D.E.K.); (V.G.P.); (E.A.P.); (M.L.)
| | - Elena A. Parakhina
- Department of Environmental Management, Peoples’ Friendship University of Russia (RUDN University), 117198 Moscow, Russia; (D.E.K.); (V.G.P.); (E.A.P.); (M.L.)
| | - Mourad Latati
- Department of Environmental Management, Peoples’ Friendship University of Russia (RUDN University), 117198 Moscow, Russia; (D.E.K.); (V.G.P.); (E.A.P.); (M.L.)
- Laboratoire d’Amélioration Intégrative des Productions Végétales (AIPV: C2711100), Ecole Nationale Supérieure Agronomique de Productions Végétales, Algiers 16200, Algeria
| | - Anvar S. Gadzhikurbanov
- Federal Research Centre “Fundamentals of Biotechnology” of the Russian Academy of Sciences, 119071 Moscow, Russia;
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Moraes WB, Madden LV, Paul PA. Characterizing Heterogeneity and Determining Sample Sizes for Accurately Estimating Wheat Fusarium Head Blight Index in Research Plots. PHYTOPATHOLOGY 2022; 112:315-334. [PMID: 34058859 DOI: 10.1094/phyto-04-21-0157-r] [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: 06/12/2023]
Abstract
Because Fusarium head blight (FHB) intensity is usually highly variable within a plot, the number of spikes rated for FHB index (IND) quantification must be considered when designing experiments. In addition, quantification of sources of IND heterogeneity is crucial for defining sampling protocols. Field experiments were conducted to quantify the variability of IND ("field severity") at different spatial scales and to investigate the effects of sample size on estimated plot-level mean IND and its accuracy. A total of 216 7-row × 6-m-long plots of a moderately resistant and a susceptible cultivar were spray-inoculated with different Fusarium graminearum spore concentrations at anthesis to generate a range of IND levels. A one-stage cluster sampling approach was used to estimate IND, with an average of 32 spikes rated at each of 10 equally spaced points per plot. Plot-level mean IND ranged from 0.9 to 37.9%. Heterogeneity of IND, quantified by fitting unconditional hierarchical linear models, was higher among spikes within clusters than among clusters within plots or among plots. The projected relative error of mean IND increased as mean IND decreased, and as sample size decreased to <100 spikes per plot. Simple random samples were drawn with replacement 50,000 times from the original dataset for each plot and used to estimate the effects of sample sizes on mean IND. Samples of 100 or more spikes resulted in more precise estimates of mean IND than smaller samples. Poor sampling may result in inaccurate estimates of IND and poor interpretation of results.
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Affiliation(s)
- Wanderson Bucker Moraes
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
| | - Laurence V Madden
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
| | - Pierce A Paul
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
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Edwards SG. Pydiflumetofen Co-Formulated with Prothioconazole: A Novel Fungicide for Fusarium Head Blight and Deoxynivalenol Control. Toxins (Basel) 2022; 14:toxins14010034. [PMID: 35051011 PMCID: PMC8778507 DOI: 10.3390/toxins14010034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 12/15/2021] [Accepted: 12/21/2021] [Indexed: 02/05/2023] Open
Abstract
Fusarium head blight (FHB) is an important disease of small grain cereals worldwide, resulting in reduced yield and quality as well as the contamination of harvested grains with mycotoxins. The key mycotoxin of concern is deoxynivalenol (DON), which has legislative and advisory limits in numerous countries. Cereal growers have a number of control options for FHB including rotation, cultivation, and varietal resistance; however, growers are still reliant on fungicides applied at flowering as part of an IPM program. Fungicides currently available to control FHB are largely restricted to triazole chemistry. This study conducted three field experiments to compare a new co-formulation of pydiflumetofen (a succinate dehydrogenase inhibitor (SDHI) with the tradename ADEPIDYN™) and prothioconazole (a triazole) against current standard fungicides at various timings (flag leaf fully emerged, mid-head emergence, early flowering, and late flowering) for the control of FHB and DON. Overall, the co-formulation showed greater efficacy compared to either pydiflumetofen alone or current fungicide chemistry. This greater activity was demonstrated over a wide range of spray timings (flag leaf fully emerged to late flowering). The availability of an SDHI with good activity against FHB and the resulting DON contamination of harvested grain will give growers an additional tool within an IPM program that will provide a greater flexibility of spray application windows and reduce fungicide resistance selection pressure.
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Affiliation(s)
- Simon G Edwards
- Crop and Environmental Sciences, Harper Adams University, Newport TF10 8NB, UK
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Madden LV, Paul PA. Is Disease Intensity a Good Surrogate for Yield Loss or Toxin Contamination? A Case Study with Fusarium Head Blight of Wheat. PHYTOPATHOLOGY 2020; 110:1632-1646. [PMID: 32370661 DOI: 10.1094/phyto-11-19-0427-r] [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: 06/11/2023]
Abstract
Sometimes plant pathologists assess disease intensity when they are primarily interested in other response variables, such as yield loss or toxin concentration in harvested products. In these situations, disease intensity potentially could be considered a surrogate of yield or toxin. A surrogate is a variable which can be used instead of the variable of interest in the evaluation of experimental treatments or in making predictions. Surrogates can be measured earlier, more conveniently, or more cheaply than the variable of primary interest, but the reliability or validity of the surrogate must be shown. We demonstrate ways of quantifying two facets of surrogacy by using a protocol originally developed by Buyse and colleagues for medical research. Coefficient-of-determination type statistics can be used to conveniently assess the strength of surrogacy on a unitless scale. As a case study, we evaluated whether field severity of Fusarium head blight (i.e., FHB index) can be used as a surrogate for yield loss and deoxynivalenol (DON) toxin concentration in harvested wheat grain. Bivariate mixed models and corresponding approximations were fitted to data from 82 uniform fungicide trials conducted from 2008 to 2013. Individual-level surrogacy-for predicting the variable of interest (yield or DON) from the surrogate (index) in plots with the same treatment-was very low. Trial-level surrogacy-for predicting the effect of treatment (e.g., mean difference) for the variable of interest based on the effect of the treatment on the surrogate (index)-was moderate for yield, and only low for DON. Challenges in using disease severity as a surrogate for yield and toxin are discussed.
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Affiliation(s)
- Laurence V Madden
- Department of Plant Pathology, Ohio State University, Wooster, OH 44691
| | - Pierce A Paul
- Department of Plant Pathology, Ohio State University, Wooster, OH 44691
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Pyszko P, Višňovská D, Drgová M, Šigut M, Drozd P. Effect of Bacterial and Fungal Microbiota Removal on the Survival and Development of Bryophagous Beetles. ENVIRONMENTAL ENTOMOLOGY 2020; 49:902-911. [PMID: 32514554 DOI: 10.1093/ee/nvaa060] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Indexed: 06/11/2023]
Abstract
Insect microbiota may play a wide range of roles in host physiology. Among others, microbiota can be involved in diet processing or protection against pathogens, both of which are potentially important in bryophagous (moss-feeding) insects, which survive on extreme diets and live in the stable environment of moss clumps suitable for the growth of fungi and bacteria. We treated Cytilus sericeus (Forster, 1771) (Coleoptera: Byrrhidae) as a model organism with bactericides and fungicides to test the effect of bacterial and fungal removal on egg hatching and larval development. Furthermore, we supplied larvae with adult feces to determine whether feces is a source of beneficial microbiota or pathogens. Bactericides had a positive effect, but fungicides had a negative effect on beetle fitness, both of which manifested during egg hatching. The feces did not play a positive role. Our conclusions indicate the presence of beneficial fungal microbiota associated with eggs but not transmitted through feces. Based on preliminary cultivation and fungicide tests, Fusarium or Penicillium may be important for suppressing pathogens, but their exact role needs to be further studied.
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Affiliation(s)
- Petr Pyszko
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Chittussiho, Ostrava, Czech Republic
| | - Denisa Višňovská
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Chittussiho, Ostrava, Czech Republic
| | - Michaela Drgová
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Chittussiho, Ostrava, Czech Republic
| | - Martin Šigut
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Chittussiho, Ostrava, Czech Republic
| | - Pavel Drozd
- Department of Biology and Ecology, Faculty of Science, University of Ostrava, Chittussiho, Ostrava, Czech Republic
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Anco DJ, Thomas JS, Monfort WS. Efficacy and Profitability of Insecticide Treatments for Tomato Spotted Wilt Management on Peanut in South Carolina. PLANT DISEASE 2020; 104:1096-1104. [PMID: 32031909 DOI: 10.1094/pdis-09-19-1829-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: 06/10/2023]
Abstract
Tomato spotted wilt (TSW) is a common and serious disease of peanut (Arachis hypogaea L.) caused by Tomato spotted wilt virus (TSWV; family Tospoviridae, genus Orthotospovirus). Management frequently uses an integrated approach, with cultivar resistance and application of in-furrow insecticide as two critical components. In-furrow insecticides help suppress thrips, which can injure and stunt young growing plants and transmit TSWV, with postemergent application of acephate capable of providing additional thrips control. To examine effects of systemic insecticides (imidacloprid, imidacloprid plus fluopyram, phorate, and acephate) on TSW management, yield, and economic return across cultivar susceptibilities (susceptible, moderately susceptible, and resistant) in South Carolina, a meta-analysis was used to synthesize results from 32 studies conducted between 2009 and 2018. Although efficacy and magnitude of individual treatments varied with susceptibility, imidacloprid increased, whereas phorate generally decreased TSW incidence relative to nontreated controls. In-furrow treatments followed by acephate further reduced TSW incidence and increased profitability. All examined treatments improved yield compared with untreated peanuts except for susceptible cultivars treated with imidacloprid. Imidacloprid plus fluopyram increased yield more than imidacloprid alone for the susceptible group, although there was little difference between these treatments in association with moderately susceptible cultivars. When comparing individual applications, phorate was overall the most profitable option across susceptibilities, although imidacloprid plus fluopyram exhibited analogous profitability for susceptible cultivars. Results from this study can be used to assist producer selection of management options for TSW in peanut.
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Affiliation(s)
- Daniel J Anco
- Department of Plant and Environmental Sciences, Edisto Research and Education Center, Clemson University, Blackville, SC 29817
| | - James S Thomas
- Department of Plant and Environmental Sciences, Edisto Research and Education Center, Clemson University, Blackville, SC 29817
| | - Walter S Monfort
- Department of Crop and Soil Sciences, University of Georgia, Tifton, GA 31793
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Shi N, Ruan H, Gan L, Dai Y, Yang X, Du Y, Chen F. Evaluating the Sensitivities and Efficacies of Fungicides with Different Modes of Action Against Phomopsis asparagi. PLANT DISEASE 2020; 104:448-454. [PMID: 31801035 DOI: 10.1094/pdis-05-19-1040-re] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Asparagus stem blight caused by Phomopsis asparagi is a major hindrance to asparagus production worldwide. Currently, fungicides are used to manage the disease in commercial production, but resistance to common fungicides has emerged in the wild population. In the present study, 132 isolates of P. asparagi collected from different provinces in China were tested for sensitivities to pyraclostrobin, tebuconazole, and fluazinam. We also determined the efficacies of six fungicides against P. asparagi. The frequency distributions of EC50 values of the isolates tested were unimodal, but the curves for pyraclostrobin and tebuconazole had long right-hand tails. The mean EC50 values for pyraclostrobin, tebuconazole, and fluazinam were 0.0426 ± 0.0029, 0.6041 ± 0.0416, and 0.0314 ± 0.0013 μg/ml, respectively. In addition, the EC50 values for pyraclostrobin were very similar with or without salicylhydroxamic acid (SHAM), 20 μg/ml, indicating that SHAM is not needed to determine the sensitivity of P. asparagi to pyraclostrobin when using the mycelial growth inhibition assay. In greenhouse assays, Merivon (42.4% fluxapyroxad plus pyraclostrobin SC), Frown-cide (500 g/liter fluazinam SC), Cabrio (250 g/liter pyraclostrobin EC), and Nativo (75% trifloxystrobin plus tebuconazole WG) showed excellent preventive efficacy against P. asparagi. And these fungicides were more effective before inoculation than when they were applied after inoculation (P < 0.05). Therefore, these fungicides should be applied prior to infection to control stem blight. In field trials, Frown-cide, Merivon, Nativo, and Cabrio also performed good control effects, ranging from 75.2 to 86.0% in 2017 and 75.4 to 87.1% in 2018. We demonstrated that Frown-cide, Merivon, Nativo, and Cabrio had considerable potential to manage asparagus stem blight. In addition, rotations of these fungicides are essential for precluding or delaying the development of resistance and for controlling the disease.
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Affiliation(s)
- Niuniu Shi
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, 350013, China, and Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Fuzhou, Fujian, 350013, China
| | - Hongchun Ruan
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, 350013, China, and Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Fuzhou, Fujian, 350013, China
| | - Lin Gan
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, 350013, China, and Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Fuzhou, Fujian, 350013, China
| | - Yuli Dai
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, 350013, China, and Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Fuzhou, Fujian, 350013, China
| | - Xiujuan Yang
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, 350013, China, and Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Fuzhou, Fujian, 350013, China
| | - Yixin Du
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, 350013, China, and Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Fuzhou, Fujian, 350013, China
| | - Furu Chen
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, 350013, China, and Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Fuzhou, Fujian, 350013, China
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Duffeck MR, Dos Santos Alves K, Machado FJ, Esker PD, Del Ponte EM. Modeling Yield Losses and Fungicide Profitability for Managing Fusarium Head Blight in Brazilian Spring Wheat. PHYTOPATHOLOGY 2020; 110:370-378. [PMID: 31713459 DOI: 10.1094/phyto-04-19-0122-r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Fusarium head blight (FHB) and wheat yield data were gathered from fungicide trials to explore their relationship. Thirty-seven studies over 9 years and 11 locations met the criteria for inclusion in the analysis: FHB index in the untreated check ≥ 5% and the range of index in a trial ≥ 4 percentage points. These studies were grouped into two baseline yields, low (Yl ≤ 3,631 kg ha-1) or high (Yh > 3,631 kg ha-1), defined based on the median of maximum yields across trials. Attainable (disease-free) yields and FHB index were predicted using a wheat crop and a disease model, respectively, in 280 simulated trials (10 planting dates in a 28-year period, 1980 to 2007) for the Passo Fundo location. The damage coefficient was then used to calculate FHB-induced yield loss (penalizing attainable yield) for each experiment. Losses were compared between periods defined as before and after FHB resurge during the early 1990s. Disease reduction from the use of one or two sprays of a triazole fungicide (tebuconazole) was also simulated, based on previous meta-analytic estimates, and the response in yield was used in a profitability analysis. Population-average intercepts but not the slopes differed significantly between Yl (2,883.6 kg ha-1) and Yh (4,419.5 kg ha-1) baseline yields and the damage coefficients were 1.60%-1 and 1.05%-1, respectively. The magnitudes and trends of simulated yield losses were in general agreement with literature reports. The risk of not offsetting the costs of one or two fungicide sprays was generally higher (>0.75) prior to FHB resurgence but fungicide profitability tended to increase in recent years, depending on the year. Our simulations allowed us to reproduce trends in historical losses, and may be further adjusted to test the effect and profitability of different control measures (host resistance, other fungicides, etc.) on quality parameters such as test weight and mycotoxin contamination, should the information become available.
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Affiliation(s)
| | | | | | - Paul David Esker
- Department of Plant Pathology and Environmental Microbiology, The Pennsylvania State University, University Park, PA 16802, U.S.A
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Wallis CM, Galarneau ERA. Phenolic Compound Induction in Plant-Microbe and Plant-Insect Interactions: A Meta-Analysis. FRONTIERS IN PLANT SCIENCE 2020; 11:580753. [PMID: 33384701 PMCID: PMC7769804 DOI: 10.3389/fpls.2020.580753] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 11/24/2020] [Indexed: 05/15/2023]
Abstract
Plants rely on a variety of ways to protect themselves from being fed upon, including de novo production of specific compounds such as those termed as phenolics. Phenolics are often described as important in plant health and numerous studies have concluded they increase as a result of insect feeding, pathogen infection, or beneficial microorganism colonization. However, there are some studies reaching differing conclusions. Therefore, meta-analyses were conducted to observe whether common trends in phenolic induction in plants can be made when they become hosts to insects or microorganisms. Four hypotheses were tested. The first was that total phenolics increase as a generic response, and meta-analyses confirmed that this occurs when plants are infested with insects or colonized by bacterial or fungal microorganisms, but not for oomycetes. The second hypothesis was that phenolic induction is different when a beneficial microorganism colonizes a plant vs. when a plant is infected by a pathogen. Beneficial bacteria, pathogenic bacteria, and beneficial fungi produced increased phenolic levels in plant hosts, but fungal pathogens did not. The third hypothesis was that insect feeding method on plant hosts determines if phenolics are induced. Chewing induced phenolics but piercing-sucking and wood-boring did not. Lastly, we used meta-analyses to determine if annual or perennials rely on phenolic induction in different amounts, and even though annuals had significantly increased phenolic levels but perennials did not, it was observed that phenolic induction was not statistically different when plant type was considered. These results demonstrate that phenolic induction is a common response in plant hosts exposed to feeding or colonization, with specific exceptions such a pathogenic fungi and piercing-sucking insects.
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Affiliation(s)
- Christopher M. Wallis
- Crop Diseases Pest and Genetics Research Unit, USDA-ARS San Joaquin Valley Agricultural Sciences Center, Parlier, CA, United States
- *Correspondence: Christopher M. Wallis
| | - Erin R.-A. Galarneau
- Viticulture and Enology Department, University of California, Davis, Davis, CA, United States
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12
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Torres A, Palacios S, Yerkovich N, Palazzini J, Battilani P, Leslie J, Logrieco A, Chulze S. Fusarium head blight and mycotoxins in wheat: prevention and control strategies across the food chain. WORLD MYCOTOXIN J 2019. [DOI: 10.3920/wmj2019.2438] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
With 744 million metric tons produced in 2017/2018, bread wheat (Triticum aestivum) and durum wheat (Triticum durum) are the second most widely produced cereal on a global basis. Prevention or control of wheat diseases may have an enormous impact on global food security and safety. Fusarium head blight is an economically debilitating disease of wheat that reduces the quantity and quality of grain harvested, and may lead to contamination with the mycotoxin deoxynivalenol, which affects the health of humans and domesticated animals. Current climate change scenarios predict an increase in the number of epidemics caused by this disease. Multiple strategies are available for managing the disease including cultural practices, planting less-susceptible cultivars, crop rotation, and chemical and biological controls. None of these strategies, however, is completely effective by itself, and an integrated approach incorporating multiple controls simultaneously is the only effective strategy to limit the disease and reduce deoxynivalenol contamination in human food and animal feed chains. This review identifies the available tools and strategies for mitigating the damage that can result from Fusarium head blight.
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Affiliation(s)
- A.M. Torres
- Research Institute on Mycology and Mycotoxicology (IMICO), UNRC-CONICET, Ruta 36, Km 601, Río Cuarto 5800, Córdoba, Argentina
| | - S.A. Palacios
- Research Institute on Mycology and Mycotoxicology (IMICO), UNRC-CONICET, Ruta 36, Km 601, Río Cuarto 5800, Córdoba, Argentina
| | - N. Yerkovich
- Research Institute on Mycology and Mycotoxicology (IMICO), UNRC-CONICET, Ruta 36, Km 601, Río Cuarto 5800, Córdoba, Argentina
| | - J.M. Palazzini
- Research Institute on Mycology and Mycotoxicology (IMICO), UNRC-CONICET, Ruta 36, Km 601, Río Cuarto 5800, Córdoba, Argentina
| | - P. Battilani
- Institute of Entomology and Plant Pathology, Faculty of Agriculture, Università Cattolica del Sacro Cuore, via Emilia Parmense 84, 29122 Piacenza, Italy
| | - J.F. Leslie
- Department of Plant Pathology, 4024 Throckmorton Plant Sciences Center, Kansas State University, Manhattan, KS 66506-5502, USA
| | - A.F. Logrieco
- National Council of Research (CNR), Institute of the Science of Food Production (ISPA), via Amendola 122/O, 70126 Bari, Italy
| | - S.N. Chulze
- Research Institute on Mycology and Mycotoxicology (IMICO), UNRC-CONICET, Ruta 36, Km 601, Río Cuarto 5800, Córdoba, Argentina
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13
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Li J, Pang Z, Duan S, Lee D, Kolbasov VG, Wang N. The in Planta Effective Concentration of Oxytetracycline Against ' Candidatus Liberibacter asiaticus' for Suppression of Citrus Huanglongbing. PHYTOPATHOLOGY 2019; 109:2046-2054. [PMID: 31369360 DOI: 10.1094/phyto-06-19-0198-r] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Huanglongbing (HLB) or greening currently is the most devastating citrus disease worldwide. The fastidious phloem-colonizing bacterium 'Candidatus Liberibacter asiaticus' (CLas) is the causal agent of citrus HLB in Florida. Bactericides containing the active ingredient oxytetracycline (OTC) have been used in foliar spray to control citrus HLB in Florida since 2016. However, the minimum concentration of OTC required to suppress CLas in planta remains unknown. We developed a new method for evaluating the effects of OTC treatment on CLas titers in infected plants and determined the relationship between OTC residue levels and control levels achieved for CLas using mathematical modeling in greenhouse and field experiments. In both greenhouse and field, OTC spray did not reduce the titers of CLas, and it produced undetectable or mild levels of OTC residue in leaves within 7 days post-application (DPA). In greenhouse, OTC injection at 0.05 g per tree decreased CLas titers to an undetectable level (cycle threshold value ≥ 36.0) from 7 to 30 DPA and produced a residue level of OTC at 0.68 to 0.73 µg/g of fresh tissue over this period. In the field, OTC injection at 0.50 g per tree resulted in the decline of CLas titers by 1.52 log reduction from 14 to 60 DPA, with residue levels of OTC at 0.27 to 0.33 µg/g of fresh tissue. In both trials, a first-order compart model of OTC residue dynamics in leaves of trunk-injected trees was specified for estimating the retention of effective concentrations. Furthermore, nonlinear modeling revealed significant positive correlations between OTC residue levels in leaves and the control levels for CLas achieved. The results suggested that the minimum concentrations of OTC required to suppress CLas populations in planta to below the detection limit are 0.68 and 0.86 µg/g and that the minimum concentrations of OTC required for initial inhibition of CLas growth in planta are ∼0.17 and ∼0.215 µg/g in leaf tissues under greenhouse and field conditions, respectively. This finding highlights that a minimum concentration of OTC should be guaranteed to be delivered to target CLas in infected plants for effective control of citrus HLB.
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Affiliation(s)
- Jinyun Li
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850
| | - Zhiqian Pang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850
| | - Shuo Duan
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850
| | - Donghwan Lee
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850
| | - Vladimir G Kolbasov
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850
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14
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Tarazona A, Mateo EM, Gómez JV, Romera D, Mateo F. Potential use of machine learning methods in assessment of Fusarium culmorum and Fusariumproliferatum growth and mycotoxin production in treatments with antifungal agents. Fungal Biol 2019; 125:123-133. [PMID: 33518202 DOI: 10.1016/j.funbio.2019.11.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 11/07/2019] [Accepted: 11/12/2019] [Indexed: 01/11/2023]
Abstract
Fusarium-controlling fungicides are necessary to limit crop loss. Little is known about the effect of antifungal formulations at sub-lethal doses, and their interaction with abiotic factors, on Fusarium culmorum and F. proliferatum development and on zearalenone and fumonisin biosynthesis, respectively. In the present study different treatments based on sulfur, trifloxystrobin and demethylation inhibitor fungicides (cyproconazole, tebuconazole and prothioconazole) under different environmental conditions, in Maize Extract Medium, are assayed in vitro. Several machine learning methods (neural networks, random forest and extreme gradient boosted trees) have been applied for the first time for modeling growth of F. culmorum and F. proliferatum and zearalenone and fumonisin production, respectively. The most effective treatment was prothioconazole, 250 g/L + tebuconazole, 150 g/L. Effective doses of this formulation for reduction or total growth inhibition ranged as follows ED50 0.49-1.70, ED90 2.57-6.02 and ED100 4.0-8.0 µg/mL, depending on the species, water activity and temperature. Overall, the growth rate and mycotoxin levels in cultures decreased when doses increased. Some treatments in combination with certain aw and temperature values significantly induced toxin production. The extreme gradient boosted tree was the model able to predict growth rate and mycotoxin production with minimum error and maximum R2 value.
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Affiliation(s)
- Andrea Tarazona
- Department of Microbiology and Ecology, University of Valencia, Valencia, Spain
| | - Eva M Mateo
- Department of Microbiology and Ecology, University of Valencia, Valencia, Spain
| | - José V Gómez
- Department of Microbiology and Ecology, University of Valencia, Valencia, Spain
| | - David Romera
- Department of Microbiology and Ecology, University of Valencia, Valencia, Spain
| | - Fernando Mateo
- Department of Electronic Engineering, ETSE, University of Valencia, Valencia, Spain.
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15
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Willbur JF, Mitchell PD, Fall ML, Byrne AM, Chapman SA, Floyd CM, Bradley CA, Ames KA, Chilvers MI, Kleczewski NM, Malvick DK, Mueller BD, Mueller DS, Kabbage M, Conley SP, Smith DL. Meta-Analytic and Economic Approaches for Evaluation of Pesticide Impact on Sclerotinia Stem Rot Control and Soybean Yield in the North Central United States. PHYTOPATHOLOGY 2019; 109:1157-1170. [PMID: 30860431 DOI: 10.1094/phyto-04-18-0124-r] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
As complete host resistance in soybean has not been achieved, Sclerotinia stem rot (SSR) caused by Sclerotinia sclerotiorum continues to be of major economic concern for farmers. Thus, chemical control remains a prevalent disease management strategy. Pesticide evaluations were conducted in Illinois, Iowa, Michigan, Minnesota, New Jersey, and Wisconsin from 2009 to 2016, for a total of 25 site-years (n = 2,057 plot-level data points). These studies were used in network meta-analyses to evaluate the impact of 10 popular pesticide active ingredients, and seven common application timings on SSR control and yield benefit, compared with not treating with a pesticide. Boscalid and picoxystrobin frequently offered the best reductions in disease severity and best yield benefit (P < 0.0001). Pesticide applications (one- or two-spray programs) made during the bloom period provided significant reductions in disease severity index (DIX) (P < 0.0001) and led to significant yield benefits (P = 0.0009). Data from these studies were also used in nonlinear regression analyses to determine the effect of DIX on soybean yield. A three-parameter logistic model was found to best describe soybean yield loss (pseudo-R2 = 0.309). In modern soybean cultivars, yield loss due to SSR does not occur until 20 to 25% DIX, and considerable yield loss (-697 kg ha-1 or -10 bu acre-1) is observed at 68% DIX. Further analyses identified several pesticides and programs that resulted in greater than 60% probability for return on investment under high disease levels.
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Affiliation(s)
- Jaime F Willbur
- 1 Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI
- 4 Department of Plant, Soil and Microbial Sciences Michigan State University, East Lansing, MI
| | - Paul D Mitchell
- 2 Department of Agricultural and Applied Economics, University of Wisconsin-Madison, Madison, WI
| | - Mamadou L Fall
- 3 Agriculture and Agri-Food Canada, Saint-Jean-sur-Richelieu, QC
- 4 Department of Plant, Soil and Microbial Sciences Michigan State University, East Lansing, MI
| | - Adam M Byrne
- 4 Department of Plant, Soil and Microbial Sciences Michigan State University, East Lansing, MI
| | - Scott A Chapman
- 5 Department of Entomology, University of Wisconsin-Madison, Madison, WI
| | - Crystal M Floyd
- 6 Department of Plant Pathology, University of Minnesota, St. Paul, MN
| | - Carl A Bradley
- 7 Department of Plant Pathology, University of Kentucky, Princeton, KY
| | - K A Ames
- 8 Department of Crop Sciences, University of Illinois, Urbana, IL
| | - Martin I Chilvers
- 4 Department of Plant, Soil and Microbial Sciences Michigan State University, East Lansing, MI
| | | | - Dean K Malvick
- 6 Department of Plant Pathology, University of Minnesota, St. Paul, MN
| | - Brian D Mueller
- 1 Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI
| | - Daren S Mueller
- 10 Department of Plant Pathology and Microbiology, Integrated Pest Management, Iowa State University, Ames, IA; and
| | - Mehdi Kabbage
- 1 Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI
| | - Shawn P Conley
- 11 Department of Agronomy, University of Wisconsin-Madison, Madison, WI
| | - Damon L Smith
- 1 Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI
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16
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Paul PA, Salgado JD, Bergstrom G, Bradley CA, Byamukama E, Byrne AM, Chapara V, Cummings JA, Chilvers MI, Dill-Macky R, Friskop A, Kleczewski N, Madden LV, Nagelkirk M, Stevens J, Smith M, Wegulo SN, Wise K, Yabwalo D. Integrated Effects of Genetic Resistance and Prothioconazole + Tebuconazole Application Timing on Fusarium Head Blight in Wheat. PLANT DISEASE 2019; 103:223-237. [PMID: 30484755 DOI: 10.1094/pdis-04-18-0565-re] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Integrated Fusarium head blight (FHB) management programs consisting of different combinations of cultivar resistance class and an application of the fungicide prothioconazole + tebuconazole at or after 50% early anthesis were evaluated for efficacy against FHB incidence (INC; percentage of diseased spikes), index (IND; percentage of diseased spikelets per spike), Fusarium damaged kernel (FDK), deoxynivalenol (DON) toxin contamination, grain yield, and test weight (TW) in inoculated field trials conducted in 11 U.S. states in 2014 and 2015. Mean log response ratios and corresponding percent control values for INC, IND, FDK, and DON, and mean differences in yield and TW relative to a nontreated, inoculated susceptible check (S_CK), were estimated through network meta-analyses as measures of efficacy. Results from the analyses were then used to estimate the economic benefit of each management program for a range of grain prices and fungicide applications costs. Management programs consisting of a moderately resistant (MR) cultivar treated with the fungicide were the most efficacious, reducing INC by 60 to 69%, IND by 71 to 76%, FDK by 66 to 72%, and DON by 60 to 64% relative to S_CK, compared with 56 to 62% for INC, 68 to 72% for IND, 66 to 68% for FDK, and 58 to 61% for DON for programs with a moderately susceptible (MS) cultivar. The least efficacious programs were those with a fungicide application to a susceptible (S) cultivar, with less than a 45% reduction of INC, IND, FDK, or DON. All programs were more efficacious under conditions favorable for FHB compared with less favorable conditions, with applications made at 50% early anthesis being of comparable efficacy to those made 2 to 7 days later. Programs with an MS cultivar resulted in the highest mean yield increases relative to S_CK (541 to 753 kg/ha), followed by programs with an S cultivar (386 to 498 kg/ha) and programs with an MR cultivar (250 to 337 kg/ha). Integrated management programs with an MS or MR cultivar treated with the fungicide at or after 50% early anthesis were the most likely to result in a 50 or 75% control of IND, FDK, or DON in a future trial. At a fixed fungicide application cost, these programs were $4 to $319/MT more economically beneficial than corresponding fungicide-only programs, depending on the cultivar and grain price. These findings demonstrate the benefits of combining genetic resistance with a prothioconazole + tebuconazole treatment to manage FHB, even if that treatment is applied a few days after 50% early anthesis.
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Affiliation(s)
- P A Paul
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
| | - J D Salgado
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
| | - G Bergstrom
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853
| | - C A Bradley
- Department of Plant Pathology, University of Kentucky Research and Education Center, Princeton, KY 42445
| | - E Byamukama
- South Dakota State University, Department of Agronomy, Horticulture, and Plant Sciences, Brookings, SD 57007
| | - A M Byrne
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824
| | - V Chapara
- North Dakota State University, Langdon Research Extension Center, Langdon, ND 58249
| | - J A Cummings
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853
| | - M I Chilvers
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824
| | - R Dill-Macky
- Department of Plant Pathology, University of Minnesota, Saint Paul, MN 55108
| | - A Friskop
- North Dakota State University, Department of Plant Pathology, Fargo, ND 58102
| | - N Kleczewski
- Department of Plant and Soil Sciences, The University of Delaware, Newark, DE 19719
| | - L V Madden
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
| | - M Nagelkirk
- Michigan State University Extension, Sandusky, MI 48471
| | - J Stevens
- University of Nebraska-Lincoln, Department of Plant Pathology, NE 68538
| | - M Smith
- Department of Plant Pathology, University of Minnesota, Northwest Research and Outreach Center, Crookston, MN 56716
| | - S N Wegulo
- University of Nebraska-Lincoln, Department of Plant Pathology, NE 68538
| | - K Wise
- Department of Plant Pathology, University of Kentucky Research and Education Center, Princeton, KY 42445
| | - D Yabwalo
- South Dakota State University, Department of Agronomy, Horticulture, and Plant Science, Brookings, SD 57007
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17
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Shah DA, De Wolf ED, Paul PA, Madden LV. Functional Data Analysis of Weather Variables Linked to Fusarium Head Blight Epidemics in the United States. PHYTOPATHOLOGY 2019; 109:96-110. [PMID: 29897307 DOI: 10.1094/phyto-11-17-0386-r] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In past efforts, input weather variables for Fusarium head blight (FHB) prediction models in the United States were identified after following some version of the window-pane algorithm, which discretizes a continuous weather time series into fixed-length windows before searching for summary variables associated with FHB risk. Functional data analysis, on the other hand, reconstructs the assumed continuous process (represented by a series of recorded weather data) by using smoothing functions, and is an alternative way of working with time series data with respect to FHB risk. Our objective was to functionally model weather-based time series data linked to 865 observations of FHB (covering 16 states and 31 years in total), classified as epidemics (FHB disease index ≥ 10%) and nonepidemics (FHB disease index < 10%). Altogether, 94 different time series variables were modeled by penalized cubic B-splines for the smoothing function, from 120 days pre-anthesis to 20 days post-anthesis. Functional mean curves, standard deviations, and first derivatives were plotted for FHB epidemics relative to nonepidemics. Function-on-scalar regressions assessed the temporal trends of the magnitude and significance of the mean difference between functionally represented weather time series associated with FHB epidemics and nonepidemics. The mean functional weather-variable curve for epidemics started to deviate, in general, from that for nonepidemics as early as 40 days pre-anthesis for several weather variables. The greatest deviations were often near anthesis, the period of maximum susceptibility of wheat to FHB-causing fungi. The most consistent separations between the mean functional curves were seen with the daily averages of moisture-related variables (such as average relative humidity) and with variables summarizing the daily variation in temperature (as opposed to the daily mean). Functional data analysis was useful for extending our knowledge of relationships between weather variables and FHB epidemics.
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Affiliation(s)
- D A Shah
- First and second authors: Department of Plant Pathology, Kansas State University, Manhattan 66506; and third and fourth authors: Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691
| | - E D De Wolf
- First and second authors: Department of Plant Pathology, Kansas State University, Manhattan 66506; and third and fourth authors: Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691
| | - P A Paul
- First and second authors: Department of Plant Pathology, Kansas State University, Manhattan 66506; and third and fourth authors: Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691
| | - L V Madden
- First and second authors: Department of Plant Pathology, Kansas State University, Manhattan 66506; and third and fourth authors: Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691
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18
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Paul PA, Bradley CA, Madden LV, Lana FD, Bergstrom GC, Dill-Macky R, Esker PD, Wise KA, McMullen M, Grybauskas A, Kirk WW, Milus E, Ruden K. Meta-Analysis of the Effects of QoI and DMI Fungicide Combinations on Fusarium Head Blight and Deoxynivalenol in Wheat. PLANT DISEASE 2018; 102:2602-2615. [PMID: 30295564 DOI: 10.1094/pdis-02-18-0211-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: 06/08/2023]
Abstract
Field trials were conducted in 17 U.S. states to evaluate the effects of quinone outside inhibitor (QoI) and demethylation inhibitor (DMI) fungicide programs on Fusarium head blight index (IND) and deoxynivalenol (DON) toxin in wheat. Four DMI-only treatments applied at Feekes 10.5.1, five QoI-only treatments applied between Feekes 9 or Feekes 10.5, three QoI+DMI mixtures applied at Feekes 10.5, and three treatments consisting of a QoI at Feekes 9 followed by a DMI at Feekes 10.5.1 were evaluated. Network meta-analytical models were fitted to log-transformed mean IND and DON data and estimated contrasts of log means were used to obtain estimates of mean percent controls relative to the nontreated check as measures of efficacy. Results from the meta-analyses were also used to assess the risk of DON increase in future trials. DMI at Feekes 10.5.1 were the most effective programs against IND and DON and the least likely to increase DON in future trials. QoI-only programs increased mean DON over the nontreated checks and were the most likely to do so in future trials, particularly when applied at Feekes 10.5. The effects of QoI+DMI combinations depended on the active ingredients and whether the two were applied as a mixture at heading or sequentially. Following a Feekes 9 QoI application with a Feekes 10.5.1 application of a DMI reduced the negative effect of the QoI on DON but was not sufficient to achieve the efficacy of the Feekes 10.5.1 DMI-only treatments. Our results suggest that one must be prudent when using QoI treatments under moderate to high risk of FHB, particularly where the QoI is used without an effective DMI applied in combination or in sequence.
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Affiliation(s)
- P A Paul
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691
| | - C A Bradley
- Department of Plant Pathology, University of Kentucky Research and Education Center, Princeton 42445
| | - L V Madden
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center
| | - F Dalla Lana
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center
| | - G C Bergstrom
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853
| | - R Dill-Macky
- Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - P D Esker
- Department of Plant Pathology and Environmental Microbiology, Penn State University, University Park 16802
| | - K A Wise
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907
| | - M McMullen
- North Dakota State University, Department of Plant Pathology, Fargo 58108
| | - A Grybauskas
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park 20742
| | - W W Kirk
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing 48824
| | - E Milus
- Department of Plant Pathology, University of Arkansas, Fayetteville 72701
| | - K Ruden
- Plant Science Department, South Dakota State University, Brookings 57007
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19
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Paul PA, Bradley CA, Madden LV, Dalla Lana F, Bergstrom GC, Dill-Macky R, Wise KA, Esker PD, McMullen M, Grybauskas A, Kirk WW, Milus E, Ruden K. Effects of Pre- and Postanthesis Applications of Demethylation Inhibitor Fungicides on Fusarium Head Blight and Deoxynivalenol in Spring and Winter Wheat. PLANT DISEASE 2018; 102:2500-2510. [PMID: 30358506 DOI: 10.1094/pdis-03-18-0466-re] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Anthesis is generally recommended as the optimum growth stage for applying a foliar fungicide to manage Fusarium head blight (FHB) and the Fusarium-associated toxin deoxynivalenol (DON) in wheat. However, because it is not always possible to treat fields at anthesis, studies were conducted to evaluate pre- and postanthesis treatment options for managing FHB and DON in spring and winter wheat. Network meta-analytical models were fitted to data from 19 years of fungicide trials, and log response ratio ([Formula: see text]) and approximate percent control ([Formula: see text]) relative to a nontreated check were estimated as measures of the effects of six treatments on FHB index (IND: mean percentage of diseased spikelets per spike) and DON. The evaluated treatments consisted of either Caramba (metconazole) applied early (at heading [CE]), at anthesis (CA), or late (5 to 7 days after anthesis; CL), or Prosaro (prothioconazole + tebuconazole) applied at the same three times and referred to as PE, PA, and PL, respectively. All treatments reduced mean IND and DON relative to the nontreated check, but the magnitude of the effect varied with timing and wheat type. CA and PA resulted in the highest [Formula: see text] values for IND, 52.2 and 51.5%, respectively, compared with 45.9% for CL, 41.3% for PL, and less than 33% for CE and PE. Anthesis and postanthesis treatments reduced mean IND by 14.9 to 29.7% relative to preanthesis treatments. The estimated effect size was also statistically significant for comparisons between CA and CL and PA and PL; CA reduced IND by 11.7% relative to CL, whereas PA reduced the disease by 17.4% relative to PL. Differences in efficacy against IND between pairs of prothioconazole + tebuconazole and metconazole treatments applied at the same timing (CE versus PE, CA versus PA, and CL versus PL) were not statistically significant. However, CA and CL outperformed PA and PL by 7 and 12.8%, respectively, in terms of efficacy against DON. All application programs had comparable efficacy against IND between spring and winter wheat types, but efficacy against DON was 10 to 16% greater for spring than winter wheat for applications made at or after anthesis. All programs led to an increase in mean grain yield and test weight relative to the nontreated check.
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Affiliation(s)
- Pierce A Paul
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, 44691
| | - Carl A Bradley
- Department of Plant Pathology, University of Kentucky Research and Education Center, Princeton, 42445
| | - Laurence V Madden
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, 44691
| | - Felipe Dalla Lana
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, 44691
| | - Gary C Bergstrom
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853
| | - Ruth Dill-Macky
- Department of Plant Pathology, University of Minnesota, Saint Paul 55108
| | - Kiersten A Wise
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907
| | - Paul D Esker
- Department of Plant Pathology and Environmental Microbiology, Pennsylvania State University, University Park, 16802
| | - Marcia McMullen
- North Dakota State University, Department of Plant Pathology, Fargo, 58108
| | - Arvydas Grybauskas
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, 20742
| | - William W Kirk
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, 48824
| | - Eugene Milus
- Department of Plant Pathology, University of Arkansas, Fayetteville, 72701
| | - Kay Ruden
- Plant Science Department, South Dakota State University, Brookings, 57007
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Kost D, Ladwig KJ, Chen L, DeSutter TM, Espinoza L, Norton LD, Smeal D, Torbert HA, Watts DB, Wolkowski RP, Dick WA. Meta-Analysis of Gypsum Effects on Crop Yields and Chemistry of Soils, Plant Tissues, and Vadose Water at Various Research Sites in the USA. JOURNAL OF ENVIRONMENTAL QUALITY 2018; 47:1284-1292. [PMID: 30272800 DOI: 10.2134/jeq2018.04.0163] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Gypsum has a long history as a soil amendment. Information on how flue gas desulfurization (FGD) gypsum affects soil, water, and plant properties across a range of climates and soils is lacking. We conducted a meta-analysis using data from 10 field sites in the United States (Alabama, Arkansas, Indiana, New Mexico, North Dakota, Ohio, and Wisconsin). Each site used three rates each of mined and FGD gypsums plus an untreated control treatment. Gypsum rates included a presumed optimal agronomic rate plus one rate lower and one rate higher than the optimal. Gypsum was applied once at the beginning of each study, and then data were collected for 2 to 3 yr. The meta-analyses used response ratios () calculated by dividing the treatment value by the control value for crop yield or for each measured element in plant, soil, and vadose water. These values were tested for their significance with values. Most values varied only slightly from 1.00. Gypsum significantly changed more values from 1.00 for vadose water than for soil or crop tissue in terms of numbers of elements affected (11 for water, 7 for soil, and 8 for crop tissue). The highest value for soil was 1.57 (Ca) which was similar for both mined and FGD gypsum, for crop tissue was 1.46 (Sr) for mined gypsum, and for vadose water was 4.22 (S) for FGD gypsum. The large increase in Ca and S is often a desired response to gypsum application. Lowest values occurred in crop tissue for Mg (0.89) with FGD gypsum and for Ni (0.92 or 0.93) with both gypsums. Although some sites showed crop yield responses to gypsum, the overall mean values for mined gypsum (0.987) and for FGD gypsum (1.00) were not significantly different from 1.00 in this short-term study.
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Nicolli CP, Machado FJ, Spolti P, Del Ponte EM. Fitness Traits of Deoxynivalenol and Nivalenol-Producing Fusarium graminearum Species Complex Strains from Wheat. PLANT DISEASE 2018; 102:1341-1347. [PMID: 30673560 DOI: 10.1094/pdis-12-17-1943-re] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Fusarium graminearum of the 15-acetyl-deoxynivalenol (15-ADON) chemotype is the main cause of Fusarium head blight (FHB) of wheat in southern Brazil. However, 3-ADON and nivalenol (NIV) chemotypes have been found in other members of the species complex causing FHB in wheat. To improve our understanding of the pathogen biology and ecology, we assessed a range of fitness-related traits in a sample of 30 strains representatives of 15-ADON (F. graminearum), 3-ADON (F. cortaderiae and F. austroamericanum), and NIV (F. meridionale and F. cortaderiae). These included perithecia formation on three cereal-based substrates, mycelial growth at two suboptimal temperatures, sporulation and germination, pathogenicity toward a susceptible and a moderately resistant cultivar, and sensitivity to tebuconazole. The most important trait favoring F. graminearum was a two times higher sexual fertility (>40% perithecial production index [PPI]) than the other species (<30% PPI); PPI varied among substrates (maize > rice > wheat). In addition, sensitivity to tebuconazole appeared lower in F. graminearum, which had the only strain with effective fungicide concentration to reduce 50% of mycelial growth >1 ppm. In the pathogenicity assays, the deoxynivalenol producers were generally more aggressive (1.5 to 2× higher final severity) toward the two cultivars, with 3-ADON or 15-ADON leading to higher area under the severity curve than the NIV strains in the susceptible and moderately resistant cultivars, respectively. There was significant variation among strains of the same species with regards asexual fertility (mycelial growth, macroconidia production, and germination), which suggested a strain- rather than a species-specific difference. These results contribute new knowledge to improve our understanding of the pathogen-related traits that may explain the dominance of certain members of the species complex in specific wheat agroecosystems.
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Affiliation(s)
- Camila Primieri Nicolli
- Departamento de Fitossanidade, Universidade Federal do Rio Grande do Sul, 91540-000, Porto Alegre, RS, Brazil
| | | | - Piérri Spolti
- Departamento de Fitopatologia, Universidade Federal de Viçosa, 36570-000, Viçosa, MG, Brazil
| | - Emerson M Del Ponte
- Departamento de Fitopatologia, Universidade Federal de Viçosa, 36570-000, Viçosa, MG, Brazil
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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.
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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
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Machado FJ, Santana FM, Lau D, Del Ponte EM. Quantitative Review of the Effects of Triazole and Benzimidazole Fungicides on Fusarium Head Blight and Wheat Yield in Brazil. PLANT DISEASE 2017; 101:1633-1641. [PMID: 30677329 DOI: 10.1094/pdis-03-17-0340-re] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Triazole and benzimidazole fungicides have been used for controlling Fusarium head blight (FHB) in wheat for over two decades. In Brazil, it was only during the last five years that uniform fungicide trials for FHB control have been established yearly, thus contributing to a new large body of fungicide efficacy data for this country. A systematic review of both peer- and non-peer-reviewed studies on chemical control conducted since 2000 in Brazil was performed. Fungicides of interest were the triazoles tebuconazole (TEBU1x and TEBU2x) and propiconazole (PROP2x), and the benzimidazole carbendazim (CARB2x). Most fungicides were applied twice, the first at early to mid-flowering and the second 7 to 10 days later. Only TEBU was tested as one or two applications, and thus four treatments were evaluated. For these fungicides, there were 35 trials reporting FHB index and 48 reporting mean yield. Network meta-analytic models were fitted to the data of the log of the means of FHB index for each fungicide and for the nontreated check. The meta-analytic estimates were used to obtain control efficacy ( C¯ ), or percent disease reduction relative to the nontreated check. The absolute mean difference ( D¯ ) in yield (kg/ha) between the fungicide-treated and the nontreated check plots was also estimated. Yield response relative to the nontreated check ( Y¯ ) was also calculated based on the difference in the logs of the means of yield between fungicide-treated and nontreated check. The TEBU1x, TEBU2x, and CARB2x treatments performed similarly with regards to control efficacy (= 59%, 53% and 55%, respectively), and although better than PROP2x (47%), the difference was marginally significant. Yield response ( D¯ ) was highest for TEBU2x, ( D¯ = 558 kg/ha, Y¯ = 19.2%) followed by PROP2x (497 kg/ha, 16.0%), TEBU1x (457 kg/ha, 17.3%), and CARB2x (456 kg/ha, 12.8%). For an average 2016 scenario of fungicide plus application costs (FC = $18 U.S./ha) and average wheat price (WP = $215 U.S./MT), the probability of breaking even on the financial investment in the four treatments ranged from 59 to 63%. For 140 scenarios (four fungicides) created based on the combination of five WP ($133 to 266 U.S./MT) and seven FC ($5 to 35 U.S./ha), the probability of breaking even was >50% for all but two scenarios. The information may serve as a guide for planning future trials and provides a baseline and first step toward optimizing FHB management in Brazil.
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Affiliation(s)
| | | | - Douglas Lau
- Embrapa Trigo, Passo Fundo, 70770-901 RS, Brazil
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Madden LV, Piepho HP, Paul PA. Statistical Models and Methods for Network Meta-Analysis. PHYTOPATHOLOGY 2016; 106:792-806. [PMID: 27111798 DOI: 10.1094/phyto-12-15-0342-rvw] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Meta-analysis, the methodology for analyzing the results from multiple independent studies, has grown tremendously in popularity over the last four decades. Although most meta-analyses involve a single effect size (summary result, such as a treatment difference) from each study, there are often multiple treatments of interest across the network of studies in the analysis. Multi-treatment (or network) meta-analysis can be used for simultaneously analyzing the results from all the treatments. However, the methodology is considerably more complicated than for the analysis of a single effect size, and there have not been adequate explanations of the approach for agricultural investigations. We review the methods and models for conducting a network meta-analysis based on frequentist statistical principles, and demonstrate the procedures using a published multi-treatment plant pathology data set. A major advantage of network meta-analysis is that correlations of estimated treatment effects are automatically taken into account when an appropriate model is used. Moreover, treatment comparisons may be possible in a network meta-analysis that are not possible in a single study because all treatments of interest may not be included in any given study. We review several models that consider the study effect as either fixed or random, and show how to interpret model-fitting output. We further show how to model the effect of moderator variables (study-level characteristics) on treatment effects, and present one approach to test for the consistency of treatment effects across the network. Online supplemental files give explanations on fitting the network meta-analytical models using SAS.
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Affiliation(s)
- L V Madden
- First and third authors: Department of Plant Pathology, Ohio State University, Wooster 44691; second author: Biostatistics Unit, Institute of Crop Science, University of Hohenheim, 70599 Stuttgart, Germany
| | - H-P Piepho
- First and third authors: Department of Plant Pathology, Ohio State University, Wooster 44691; second author: Biostatistics Unit, Institute of Crop Science, University of Hohenheim, 70599 Stuttgart, Germany
| | - P A Paul
- First and third authors: Department of Plant Pathology, Ohio State University, Wooster 44691; second author: Biostatistics Unit, Institute of Crop Science, University of Hohenheim, 70599 Stuttgart, Germany
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Salgado JD, Madden LV, Paul PA. Efficacy and Economics of Integrating In-Field and Harvesting Strategies to Manage Fusarium Head Blight of Wheat. PLANT DISEASE 2014; 98:1407-1421. [PMID: 30703933 DOI: 10.1094/pdis-01-14-0093-re] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Fusarium head blight (FHB), a fungal disease of wheat caused by Fusarium graminearum, and its associated toxins, particularly deoxynivalenol (DON), are best managed by integrating multiple strategies. Experiments were established in 2011 and 2013 to evaluate the effects of integrating cultivar resistance, fungicide application, and grain harvesting strategy on FHB index (IND; field severity), DON, grain yield (YLD), and grain test weight (TW; weight per unit volume). Plots of two moderately resistant and two susceptible cultivars were either treated with 19% tebuconazole + 19% prothioconazole or left untreated, and then inoculated with F. graminearum. IND was rated as the mean percentage of diseased spikelets per spike. Separate subsets of the plots of each cultivar-treatment combination were harvested with one of two combine harvester configuration: C1 (the default, set at a fan speed of 1,375 rpm and a shutter opening of 70 mm) and C4 (modified, with the same fan speeds but a wider shutter opening of 90 mm). YLD and TW data were collected, and grain samples were rated for percent Fusarium-damaged kernels (FDK) and tested for DON. Results from linear mixed-model analyses showed that the cultivar-treatment interaction was significant for all FHB-related responses, with the magnitude of the difference in mean arcsine-square-root-transformed IND and FDK (arcIND and arcFDK) and log-transformed DON (logDON) between treated and untreated being higher for susceptible than moderately resistant cultivars. Plots harvested with the C4 combine configuration had significantly higher mean TW than those harvested with C1. Treated plots had significantly higher YLD and TW than untreated plots, regardless of cultivar and configuration. Relative to the reference management program (untreated, susceptible cultivar, harvested with C1), the greatest percent reduction in FDK and DON and increase in YLD was observed for programs that included moderate resistance and fungicide treatment. The greatest percent increase in TW relative to the reference was observed when C4 adjusted combine setting was integrated with resistance and fungicide. Overall, the most effective management programs all included fungicide treatment, two included moderate resistance, and two included C4 combine setting. Relative to the reference management program, these programs resulted in 30 to 51% reduction in total estimated price discount, $127 to 312 ha-1 increase in gross cash income, and economic benefit of $31 to 272 ha-1, depending on the level of FHB IND (5 to 15%), grain price ($118 to 276 metric ton-1), and fungicide application cost ($40 to 96 ha-1).
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Affiliation(s)
- Jorge David Salgado
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691
| | - Laurence V Madden
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691
| | - Pierce A Paul
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691
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D'Angelo DL, Bradley CA, Ames KA, Willyerd KT, Madden LV, Paul PA. Efficacy of Fungicide Applications During and After Anthesis Against Fusarium Head Blight and Deoxynivalenol in Soft Red Winter Wheat. PLANT DISEASE 2014; 98:1387-1397. [PMID: 30703938 DOI: 10.1094/pdis-01-14-0091-re] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Seven field experiments were conducted in Ohio and Illinois between 2011 and 2013 to evaluate postanthesis applications of prothioconazole + tebuconazole and metconazole for Fusarium head blight and deoxynivalenol (DON) control in soft red winter wheat. Treatments consisted of an untreated check and fungicide applications made at early anthesis (A), 2 (A+2), 4 (A+4), 5 (A+5), or 6 (A+6) days after anthesis. Six of the seven experiments were augmented with artificial Fusarium graminearum inoculum, and the other was naturally infected. FHB index (IND), Fusarium damaged kernels (FDK), and DON concentration of grain were quantified. All application timings led to significantly lower mean arcsine-square-root-transformed IND and FDK (arcIND and arcFDK) and log-transformed (logDON) than in the untreated check; however, arcIND, arcFDK, and logDON for the postanthesis applications were generally not significantly different from those for the anthesis applications. Relative to the check, A+2 resulted in the highest percent control for both IND and DON, 69 and 54%, respectively, followed by A+4 (62 and 52%), A+6 (62 and 48%), and A (56 and 50%). A+2 and A+6 significantly reduced IND by 30 and 14%, respectively, relative to the anthesis application. Postanthesis applications did not, however, reduce DON relative to the anthesis application. These results suggest that applications made up to 6 days following anthesis may be just as effective as, and sometimes more effective than, anthesis applications at reducing FHB and DON.
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Affiliation(s)
- D L D'Angelo
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
| | - C A Bradley
- Department of Crop Sciences, University of Illinois, Urbana, IL 61801
| | - K A Ames
- Department of Crop Sciences, University of Illinois, Urbana, IL 61801
| | - K T Willyerd
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
| | - L V Madden
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
| | - P A Paul
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
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Andersen KF, Morris L, Derksen RC, Madden LV, Paul PA. Rainfastness of Prothioconazole + Tebuconazole for Fusarium Head Blight and Deoxynivalenol Management in Soft Red Winter Wheat. PLANT DISEASE 2014; 98:1398-1406. [PMID: 30703929 DOI: 10.1094/pdis-01-14-0092-re] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Fungicides are most warranted for control of Fusarium head blight (FHB), a disease of wheat caused by the fungal pathogen Fusarium graminearum, when wet, rainy conditions occur during anthesis. However, it is unclear whether rainfall directly following application affects fungicide efficacy against FHB and its associated toxin, deoxynivalenol (DON). The objective of this study was to determine the rainfastness of the fungicide tebuconazole + prothioconazole and the residual life of tebuconazole when applied to wheat spikes at anthesis in combination with the nonionic surfactant Induce. Three field experiments were conducted during 2012 and 2013 in Wooster, OH. Simulated rainfall of a fixed intensity and duration was applied to separate plots at five different times after the fungicide treatment (0, 60, 105, 150, or 195 min). Spike samples were collected at 4-day intervals after fungicide application and assayed for tebuconazole residue. A similar set of greenhouse experiments was conducted using six post-fungicide-application rainfall timing treatments (0, 15, 30, 60, 120, or 180 min). All experiments were inoculated at anthesis with spores of F. graminearum, and FHB index (IND) and DON were quantified. In four of the five experiments, all fungicide-treated experimental units (EUs) had significantly lower mean IND and DON than the untreated check, regardless of rainfall treatment. Among rainfall treatments, EUs that received the earliest rains after fungicide application tended to have the highest numerical mean IND and DON, but were generally not significantly different from EUs that received later rain or fungicide without rain. In both years, fungicide residue on wheat spikes decreased rapidly with time after application, but the rate of reduction varied somewhat between years, with a half-life of 6 to 9 days. Rainfall treatment did not have a significant effect on the rate of residue reduction or the level of residue at a fixed sampling time after fungicide application. In this study, tebuconazole + prothioconazole mixed with a nonionic surfactant was fairly rainfast for a fixed set of rainfall characteristics, and tebuconazole residue did not persist very long after application on wheat spikes.
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Affiliation(s)
- K F Andersen
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
| | - L Morris
- USDA-ARS, Application Technology Research Unit, Wooster, OH 44691
| | - R C Derksen
- USDA-ARS, Application Technology Research Unit, Wooster, OH 44691
| | - L V Madden
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
| | - P A Paul
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster, OH 44691
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Liu Y, Chen X, Jiang J, Hamada MS, Yin Y, Ma Z. Detection and dynamics of different carbendazim-resistance conferring β-tubulin variants of Gibberella zeae collected from infected wheat heads and rice stubble in China. PEST MANAGEMENT SCIENCE 2014; 70:1228-1236. [PMID: 24302656 DOI: 10.1002/ps.3680] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 09/25/2013] [Accepted: 11/06/2013] [Indexed: 06/02/2023]
Abstract
BACKGROUND Carbendazim has been used in the control of Fusarium head blight (FHB) for more than 30 years in China. Thus, carbendazim-resistant (Car(R) ) populations of Gibberella zeae have developed in some areas. In this study, 9341 G. zeae isolates were collected from the ten main wheat-producing regions of China in the period from 2008 to 2012, and sensitivity to carbendazim was detected. RESULTS A high frequency of Car(R) isolates was observed in Zhejiang and Jiangsu provinces. Car(R) isolates were recovered from Anhui and Henan provinces in 2009 and 2012, respectively, but were not detected in the other six regions. Available (F167Y, E198Q and F200Y) and newly developed (E198L and E198K) allele-specific PCR assays were used to genotype field Car(R) isolates. The β-tubulin variants harbouring point mutation F167Y or E198Q accounted for >95% in Car(R) populations. Quantitative allele-specific real-time PCR assays were developed to determine the frequencies of five different β-tubulin variants present in populations of perithecia sampled from rice stubble. CONCLUSION Car(R) populations of G. zeae develop rapidly under the selection pressure of carbendazim. Real-time PCR assays detecting the resistance frequencies in populations of perithecia would provide useful information for FHB control and management of resistance.
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Affiliation(s)
- Ye Liu
- Institute of Biotechnology, Zhejiang University, Hangzhou, China
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Lehoczki-Krsjak S, Varga M, Szabó-Hevér Á, Mesterházy Á. Translocation and degradation of tebuconazole and prothioconazole in wheat following fungicide treatment at flowering. PEST MANAGEMENT SCIENCE 2013; 69:1216-1224. [PMID: 23471588 DOI: 10.1002/ps.3486] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 12/06/2012] [Accepted: 01/03/2013] [Indexed: 06/01/2023]
Abstract
BACKGROUND Prothioconazole and tebuconazole are among the most effective fungicides against Fusarium head blight (FHB) of wheat (Triticum aestivum L.). The translocation between the ears and the flag leaves and the kinetics of degradation may influence field efficacy of these active ingredients (AIs). RESULTS In greenhouse experiments, only traces (<1%) of the total AI content translocated from the flag leaves to the ears, and a maximum of 3.55% from the ears to the flag leaves. From the treated to the non-treated side of the ears, 3.2-15.9% of the AI translocated, depending on cultivar, AI and time. In field experiments, the degradation kinetics in the first 8 days after treatment revealed a higher velocity in the flag leaf blades than in the ears, although both were dependent on the type of cultivar. The fungicide treatment resulted in 42.6-100% decreases in FHB traits. CONCLUSIONS There is no effective translocation of these AIs, only moderate redistribution in the ears, which can be decisive from the aspect of FHB management. The degradation of prothioconazole was faster than that of tebuconazole. Cultivar and environmental effects influenced the degradation kinetics of these AIs, but a high level of protection against FHB was maintained.
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Shah DA, Molineros JE, Paul PA, Willyerd KT, Madden LV, De Wolf ED. Predicting fusarium head blight epidemics with weather-driven pre- and post-anthesis logistic regression models. PHYTOPATHOLOGY 2013; 103:906-919. [PMID: 23527485 DOI: 10.1094/phyto-11-12-0304-r] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Our objective was to identify weather-based variables in pre- and post-anthesis time windows for predicting major Fusarium head blight (FHB) epidemics (defined as FHB severity ≥ 10%) in the United States. A binary indicator of major epidemics for 527 unique observations (31% of which were major epidemics) was linked to 380 predictor variables summarizing temperature, relative humidity, and rainfall in 5-, 7-, 10-, 14-, or 15-day-long windows either pre- or post-anthesis. Logistic regression models were built with a training data set (70% of the 527 observations) using the leaps-and-bounds algorithm, coupled with bootstrap variable and model selection methods. Misclassification rates were estimated on the training and remaining (test) data. The predictive performance of models with indicator variables for cultivar resistance, wheat type (spring or winter), and corn residue presence was improved by adding up to four weather-based predictors. Because weather variables were intercorrelated, no single model or subset of predictor variables was best based on accuracy, model fit, and complexity. Weather-based predictors in the 15 final empirical models selected were all derivatives of relative humidity or temperature, except for one rainfall-based predictor, suggesting that relative humidity was better at characterizing moisture effects on FHB than other variables. The average test misclassification rate of the final models was 19% lower than that of models currently used in a national FHB prediction system.
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Affiliation(s)
- D A Shah
- Department of Plant Pathology, Kansas State University, Manhattan 66506, USA.
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Wegulo SN. Factors influencing deoxynivalenol accumulation in small grain cereals. Toxins (Basel) 2012; 4:1157-80. [PMID: 23202310 PMCID: PMC3509702 DOI: 10.3390/toxins4111157] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 10/24/2012] [Accepted: 11/02/2012] [Indexed: 11/17/2022] Open
Abstract
Deoxynivalenol (DON) is a mycotoxin produced by the plant pathogenic fungi Fusarium graminearum and F. culmorum. These and other closely related fungi cause a disease known as Fusarium head blight (FHB) in small grain cereals. Other mycotoxins produced by FHB-causing fungi include nivalenol, T-2 toxin, and zearalenone. Ingestion of mycotoxin-contaminated food and feed can lead to toxicosis in humans and animals, respectively. DON is the predominant and most economically important of these mycotoxins in the majority of small grain-producing regions of the world. This review examines the factors that influence DON accumulation in small grain cereals from an agricultural perspective. The occurrence and economic importance of FHB and DON in small grain cereals, epidemiological factors and cereal production practices that favor FHB development and DON accumulation in grain under field conditions, and regulatory/advisory standards for DON in food and feed are discussed. This information can be used to develop strategies that reduce DON accumulation in grain before harvest and to mitigate the human and animal health risks associated with DON contamination of food and feed.
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Affiliation(s)
- Stephen N Wegulo
- Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, NE 68583, USA.
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Willyerd KT, Li C, Madden LV, Bradley CA, Bergstrom GC, Sweets LE, McMullen M, Ransom JK, Grybauskas A, Osborne L, Wegulo SN, Hershman DE, Wise K, Bockus WW, Groth D, Dill-Macky R, Milus E, Esker PD, Waxman KD, Adee EA, Ebelhar SE, Young BG, Paul PA. Efficacy and Stability of Integrating Fungicide and Cultivar Resistance to Manage Fusarium Head Blight and Deoxynivalenol in Wheat. PLANT DISEASE 2012; 96:957-967. [PMID: 30727217 DOI: 10.1094/pdis-09-11-0763] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Integration of host resistance and prothioconazole + tebuconazole fungicide application at anthesis to manage Fusarium head blight (FHB) and deoxynivalenol (DON) in wheat was evaluated using data from over 40 trials in 12 U.S. states. Means of FHB index (index) and DON from up to six resistance class-fungicide management combinations per trial (susceptible treated [S_TR] and untreated [S_UT]; moderately susceptible treated [MS_TR] and untreated [MS_UT]; moderately resistant treated [MR_TR] and untreated [MR_UT]) were used in multivariate meta-analyses, and mean log response ratios across trials were estimated and transformed to estimate mean percent control ( ) due to the management combinations relative to S_UT. All combinations led to a significant reduction in index and DON (P < 0.001). MR_TR was the most effective combination, with a of 76% for index and 71% for DON, followed by MS_TR (71 and 58%, respectively), MR_UT (54 and 51%, respectively), S_TR (53 and 39%, respectively), and MS_UT (43 and 30%, respectively). Calculations based on the principle of treatment independence showed that the combination of fungicide application and resistance was additive in terms of percent control for index and DON. Management combinations were ranked based on percent control relative to S_UT within each trial, and nonparametric analyses were performed to determine management combination stability across environments (trials) using the Kendall coefficient of concordance (W). There was a significant concordance of management combinations for both index and DON (P < 0.001), indicating a nonrandom ranking across environments and relatively low variability in the within-environment ranking of management combinations. MR_TR had the highest mean rank (best control relative to S_UT) and was one of the most stable management combinations across environments, with low rank stability variance (0.99 for index and 0.67 for DON). MS_UT had the lowest mean rank (poorest control) but was also one of the most stable management combinations. Based on Piepho's nonparametric rank-based variance homogeneity U test, there was an interaction of management combination and environment for index (P = 0.011) but not for DON (P = 0.147), indicating that the rank ordering for index depended somewhat on environment. In conclusion, although the magnitude of percent control will likely vary among environments, integrating a single tebuconazole + prothioconazole application at anthesis with cultivar resistance will be a more effective and stable management practice for both index and DON than either approach used alone.
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Affiliation(s)
- K T Willyerd
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691
| | - C Li
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691
| | - L V Madden
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691
| | - C A Bradley
- Department of Crop Sciences, University of Illinois, Urbana 61801
| | - G C Bergstrom
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, NY 14853
| | - L E Sweets
- Division of Plant Sciences, University of Missouri, Columbia 65211
| | | | - J K Ransom
- Department of Plant Sciences, North Dakota State University, Fargo 58108
| | - A Grybauskas
- Department of Plant Science and Landscape Management, University of Maryland, College Park 20742
| | - L Osborne
- Pioneer Hi-Bred International, Brookings SD 57006
| | - S N Wegulo
- Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln 68583
| | - D E Hershman
- Department of Plant Pathology, The University of Kentucky, Princeton, 42445
| | - K Wise
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907
| | - W W Bockus
- Department of Plant Pathology, Kansas State University, Manhattan 66506
| | - D Groth
- Louisiana State University Agricultural Center Rice Research Station, Rayne 70578
| | - R Dill-Macky
- Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - E Milus
- Department of Plant Pathology, University of Arkansas, Fayetteville 72701
| | - P D Esker
- Department of Plant Pathology, University of Wisconsin-Madison, Madison 53706
| | - K D Waxman
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University
| | - E A Adee
- Department of Crop Sciences, University of Illinois
| | - S E Ebelhar
- Department of Crop Sciences, University of Illinois
| | - B G Young
- Department of Plant, Soil, and Agricultural Systems, Southern Illinois University, Carbondale 62901
| | - P A Paul
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center
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33
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Yoshida M, Nakajima T, Tomimura K, Suzuki F, Arai M, Miyasaka A. Effect of the Timing of Fungicide Application on Fusarium Head Blight and Mycotoxin Contamination in Wheat. PLANT DISEASE 2012; 96:845-851. [PMID: 30727359 DOI: 10.1094/pdis-10-11-0819] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Fungicide application to control Fusarium head blight (FHB) and accompanying mycotoxin contamination in wheat is generally performed at anthesis because wheat is most susceptible to FHB around this stage. In this study, we evaluated the effect of the timing of fungicide application on FHB and mycotoxin (deoxynivalenol and nivalenol) accumulation in wheat based on our previous finding that the late period of grain development (beyond 20 days after anthesis [DAA]) is important to determine the final toxin contamination level in wheat. Thiophanate-methyl fungicide was tested under artificial inoculation conditions in which moisture and inoculum spores were provided throughout the testing period. Eight treatments differing in application timing (anthesis, 10, 20, and 30 DAA) and in the number of applications (0 to 2) were tested for 2 years. The results indicated that fungicide application timing differentially affects FHB (disease) and mycotoxin concentration. Fungicide application at 20 DAA reduced mycotoxin concentration in matured grain without reducing FHB severity, whereas application at anthesis was crucial for reducing FHB. These results and our previous findings suggest that around 20 DAA (late milk stage) is a potentially critical timing for mycotoxin control in wheat.
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Affiliation(s)
- Megumi Yoshida
- NARO Kyushu Okinawa Agricultural Research Center (NARO/KARC), 2421 Suya, Koshi, Kumamoto 861-1192, Japan
| | - Takashi Nakajima
- NARO Kyushu Okinawa Agricultural Research Center (NARO/KARC), 2421 Suya, Koshi, Kumamoto 861-1192, Japan
| | - Kenta Tomimura
- NARO Kyushu Okinawa Agricultural Research Center (NARO/KARC), 2421 Suya, Koshi, Kumamoto 861-1192, Japan
| | - Fumihiko Suzuki
- NARO Kyushu Okinawa Agricultural Research Center (NARO/KARC), 2421 Suya, Koshi, Kumamoto 861-1192, Japan
| | - Michiyoshi Arai
- NARO Kyushu Okinawa Agricultural Research Center (NARO/KARC), 2421 Suya, Koshi, Kumamoto 861-1192, Japan
| | - Atsushi Miyasaka
- NARO Kyushu Okinawa Agricultural Research Center (NARO/KARC), 2421 Suya, Koshi, Kumamoto 861-1192, Japan
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Bernhoft A, Torp M, Clasen PE, Løes AK, Kristoffersen AB. Influence of agronomic and climatic factors on Fusarium infestation and mycotoxin contamination of cereals in Norway. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2012; 29:1129-40. [PMID: 22494553 PMCID: PMC3379782 DOI: 10.1080/19440049.2012.672476] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A total of 602 samples of organically and conventionally grown barley, oats and wheat was collected at grain harvest during 2002-2004 in Norway. Organic and conventional samples were comparable pairs regarding cereal species, growing site and harvest time, and were analysed for Fusarium mould and mycotoxins. Agronomic and climatic factors explained 10-30% of the variation in Fusarium species and mycotoxins. Significantly lower Fusarium infestation and concentrations of important mycotoxins were found in the organic cereals. The mycotoxins deoxynivalenol (DON) and HT-2 toxin (HT-2) constitute the main risk for human and animal health in Norwegian cereals. The impacts of various agronomic and climatic factors on DON and HT-2 as well as on their main producers F. graminearum and F. langsethiae and on total Fusarium were tested by multivariate statistics. Crop rotation with non-cereals was found to reduce all investigated characteristics significantly--mycotoxin concentrations as well as various Fusarium infestations. No use of mineral fertilisers and herbicides was also found to decrease F. graminearum, whereas lodged fields increased the occurrence of this species. No use of herbicides was also found to decrease F. langsethiae, but for this species the occurrence was lower in lodged fields. Total Fusarium infestation was decreased with no use of fungicides or mineral fertilisers, and with crop rotation, as well as by using herbicides and increased by lodged fields. Clay and to some extent silty soils seemed to reduce F. graminearum in comparison with sandy soils. Concerning climate factors, low temperature before grain harvest was found to increase DON; and high air humidity before harvest to increase HT-2. F. graminearum was negatively correlated with precipitation in July but correlated with air humidity before harvest. F. langsethiae was correlated with temperature in July. Total Fusarium increased with increasing precipitation in July. Organic cereal farmers have fewer cereal intense rotations than conventional farmers. Further, organic farmers do not apply mineral fertiliser or pesticides (fungicides, herbicides or insecticides), and have less problem with lodged fields. The study showed that these agronomic factors were related to the infestation of Fusarium species and the concentration of mycotoxins. Hence, it is reasonable to conclude that farming system (organic versus conventional) impacts Fusarium infestation, and that organic management tends to reduce Fusarium and mycotoxins. However, Fusarium infestation and mycotoxin concentrations may be influenced by a range of factors not studied here, such as local topography and more local climate, as well as cereal species and variety.
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Affiliation(s)
- A Bernhoft
- Norwegian Veterinary Institute, PO Box 750 Sentrum, NO-0106 Oslo, Norway.
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35
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Salgado JD, Wallhead M, Madden LV, Paul PA. Grain Harvesting Strategies to Minimize Grain Quality Losses Due to Fusarium Head Blight in Wheat. PLANT DISEASE 2011; 95:1448-1457. [PMID: 30731788 DOI: 10.1094/pdis-04-11-0309] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Fusarium head blight (FHB) reduces wheat grain yield and quality, leading to price discounts due to Fusarium-damaged kernels (FDK), deoxynivalenol (DON) contamination of grain, and reduced test weight (weight per unit volume of grain). Experiments were conducted to determine whether changing combine harvester configurations to differentially remove diseased kernels affected the yield and quality of grain harvested from plots with different mean levels of FHB index (IND, mean proportion of diseased spikelets per spike), achieved with inoculations at different spore densities. Plots were harvested using four combine configurations, with C1 being the standard, set at a fan speed of 1,375 rpm and a shutter opening of 70 mm, and C2, C3, and C4 regulated to fan speeds and shutter openings of 1,475 rpm and 70 mm, 1,475 rpm and 90 mm, and 1,375 rpm and 90 mm, respectively. C3 and C4 consistently had significantly lower mean arcsine-transformed FDK and log-transformed DON and higher mean test weight than did C1. However, C3 and C4 also resulted in significantly lower mean amounts of harvested grain than did C1. The estimated mean responses to combine configuration were consistent across a range of mean IND levels (5 to 35%). Using a common price discount schedule based on the incidence of FDK, DON, and test weight, and the mean values found in the current investigation for these grain-quality variables, configurations C2, C3, and C4 resulted in between $10 and 40/t lower estimated grain price discounts than C1, with the lowest discounts corresponding to C3 and C4. Using the discount values, a range of grain prices, and the mean yield values from this investigation, estimated gross cash income (GCI; mean estimated yield × grain price adjusted for discounts due to inferior quality) was generally higher for grain harvested with C2 and C4 than with C1 or C3, with C4 being the most consistent across a range of IND levels (5 to 35%) and grain prices ($118 to 276/t). For all modified configurations, the greatest increases in GCI over C1 were observed at the lowest tested grain price, and the improvement of GCI over C1 increased with increasing IND up to the highest disease level tested. Thus, these results showed that, when harvesting grain from FHB-affected fields, the improvement in grain quality and reduction in price discounts with a combine adjustment could be great enough to counteract the reduction in harvested grain that results from the adjustment.
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Affiliation(s)
- Jorge David Salgado
- Department of Plant Pathology, Ohio State University and the Ohio Agricultural Research and Development Center, Wooster 44691
| | - Matthew Wallhead
- Department of Plant Pathology, Ohio State University and the Ohio Agricultural Research and Development Center, Wooster 44691
| | - Laurence V Madden
- Department of Plant Pathology, Ohio State University and the Ohio Agricultural Research and Development Center, Wooster 44691
| | - Pierce A Paul
- Department of Plant Pathology, Ohio State University and the Ohio Agricultural Research and Development Center, Wooster 44691
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36
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Mesterházy Á, Tóth B, Varga M, Bartók T, Szabó-Hevér Á, Farády L, Lehoczki-Krsjak S. Role of fungicides, application of nozzle types, and the resistance level of wheat varieties in the control of Fusarium head blight and deoxynivalenol. Toxins (Basel) 2011; 3:1453-83. [PMID: 22174980 PMCID: PMC3237006 DOI: 10.3390/toxins3111453] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2011] [Revised: 11/03/2011] [Accepted: 11/03/2011] [Indexed: 12/04/2022] Open
Abstract
Fungicide application is a key factor in the control of mycotoxin contamination in the harvested wheat grain. However, the practical results are often disappointing. In 2000-2004, 2006-2008 and 2007 and 2008, three experiments were made to test the efficacy of fungicide control on Fusarium Head Blight (FHB) in wheat and to find ways to improve control of the disease and toxin contamination. In a testing system we have used for 20 years, tebuconazole and tebuconazole + prothioconazole fungicides regularly reduced symptoms by about 80% with a correlating reduction in toxin contamination. Averages across the years normally show a correlation of r = 0.90 or higher. The stability differences (measured by the stability index) between the poorest and the best fungicides are about 10 or more times, differing slightly in mycotoxin accumulation, FHB index (severity) and Fusarium damaged kernels (FDK). The weak fungicides, like carbendazim, were effective only when no epidemic occurred or epidemic severity was at a very low level. Similar fungicide effects were seen on wheat cultivars which varied in FHB resistance. In this study, we found three fold differences in susceptibility to FHB between highly susceptible and moderately resistant cultivars when treated with fungicides. In the moderately resistant cultivars, about 50% of the fungicide treatments lowered the DON level below the regulatory limit. In the most susceptible cultivars, all fungicides failed to reduce mycotoxin levels low enough for grain acceptance, in spite of the fact that disease was significantly reduced. The results correlated well with the results of the large-scale field tests of fungicide application at the time of natural infection. The Turbo FloodJet nozzle reduced FHB incidence and DON contamination when compared to the TeeJet XR nozzle. Overall, the data suggest that significant decreases in FHB incidence and deoxynivalenol contamination in field situations are possible with proper fungicide applications. Additionally, small plot tests can be used to evaluate the quality of the field disease and toxin production.
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Affiliation(s)
- Ákos Mesterházy
- Cereal Research Non-profit Company, H-6701 Szeged, P.O. Box 391, Hungary; (B.T.); (M.V.); (T.B.); (Á.S.-H.); (S.L.-K.)
| | - Beáta Tóth
- Cereal Research Non-profit Company, H-6701 Szeged, P.O. Box 391, Hungary; (B.T.); (M.V.); (T.B.); (Á.S.-H.); (S.L.-K.)
| | - Monika Varga
- Cereal Research Non-profit Company, H-6701 Szeged, P.O. Box 391, Hungary; (B.T.); (M.V.); (T.B.); (Á.S.-H.); (S.L.-K.)
| | - Tibor Bartók
- Cereal Research Non-profit Company, H-6701 Szeged, P.O. Box 391, Hungary; (B.T.); (M.V.); (T.B.); (Á.S.-H.); (S.L.-K.)
| | - Ágnes Szabó-Hevér
- Cereal Research Non-profit Company, H-6701 Szeged, P.O. Box 391, Hungary; (B.T.); (M.V.); (T.B.); (Á.S.-H.); (S.L.-K.)
| | - László Farády
- Bayer Hungaria Ltd., Alkotas Str. 50, 1123 Budapest, Hungary;
| | - Szabolcs Lehoczki-Krsjak
- Cereal Research Non-profit Company, H-6701 Szeged, P.O. Box 391, Hungary; (B.T.); (M.V.); (T.B.); (Á.S.-H.); (S.L.-K.)
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37
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Paul PA, Madden LV, Bradley CA, Robertson AE, Munkvold GP, Shaner G, Wise KA, Malvick DK, Allen TW, Grybauskas A, Vincelli P, Esker P. Meta-analysis of yield response of hybrid field corn to foliar fungicides in the U.S. Corn Belt. PHYTOPATHOLOGY 2011; 101:1122-32. [PMID: 21554185 DOI: 10.1094/phyto-03-11-0091] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The use of foliar fungicides on field corn has increased greatly over the past 5 years in the United States in an attempt to increase yields, despite limited evidence that use of the fungicides is consistently profitable. To assess the value of using fungicides in grain corn production, random-effects meta-analyses were performed on results from foliar fungicide experiments conducted during 2002 to 2009 in 14 states across the United States to determine the mean yield response to the fungicides azoxystrobin, pyraclostrobin, propiconazole + trifloxystrobin, and propiconazole + azoxystrobin. For all fungicides, the yield difference between treated and nontreated plots was highly variable among studies. All four fungicides resulted in a significant mean yield increase relative to the nontreated plots (P < 0.05). Mean yield difference was highest for propiconazole + trifloxystrobin (390 kg/ha), followed by propiconazole + azoxystrobin (331 kg/ha) and pyraclostrobin (256 kg/ha), and lowest for azoxystrobin (230 kg/ha). Baseline yield (mean yield in the nontreated plots) had a significant effect on yield for propiconazole + azoxystrobin (P < 0.05), whereas baseline foliar disease severity (mean severity in the nontreated plots) significantly affected the yield response to pyraclostrobin, propiconazole + trifloxystrobin, and propiconazole + azoxystrobin but not to azoxystrobin. Mean yield difference was generally higher in the lowest yield and higher disease severity categories than in the highest yield and lower disease categories. The probability of failing to recover the fungicide application cost (p(loss)) also was estimated for a range of grain corn prices and application costs. At the 10-year average corn grain price of $0.12/kg ($2.97/bushel) and application costs of $40 to 95/ha, p(loss) for disease severity <5% was 0.55 to 0.98 for pyraclostrobin, 0.62 to 0.93 for propiconazole + trifloxystrobin, 0.58 to 0.89 for propiconazole + azoxystrobin, and 0.91 to 0.99 for azoxystrobin. When disease severity was >5%, the corresponding probabilities were 0.36 to 95, 0.25 to 0.69, 0.25 to 0.64, and 0.37 to 0.98 for the four fungicides. In conclusion, the high p(loss) values found in most scenarios suggest that the use of these foliar fungicides is unlikely to be profitable when foliar disease severity is low and yield expectation is high.
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Affiliation(s)
- P A Paul
- Department of Plant Pathology, The Ohio State University, OH, USA.
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38
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Ngugi HK, Lehman BL, Madden LV. Multiple treatment meta-analysis of products evaluated for control of fire blight in the eastern United States. PHYTOPATHOLOGY 2011; 101:512-22. [PMID: 21244224 DOI: 10.1094/phyto-08-10-0221] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The aim of this analysis was to estimate the effect sizes and consistency of products evaluated for fire blight control in the eastern United States over the last decade. Because only 3% of the 69 studies published from 2000 to 2008 explicitly presented a measure of within-study variability, a method for estimating the least significant difference (LSD) and, hence the sampling variance, for studies with at least two significant mean separations in the presented mean multiple comparisons was developed. Lin's concordance analysis indicated that the estimated LSD was an accurate predictor of the actual LSD based on 35 studies in a calibration evaluation (ρ(c) = 0.997). Separate multi-treatment random-effects meta-analyses were performed for three control categories: antibiotics, biological control, and plant defense-activating products and mean log response ratios relative to the nontreated controls ([Formula: see text]) were computed for each treatment and then back-transformed to obtain the mean percent disease control. None of the products evaluated performed as well as streptomycin, the standard product for fire blight control, for which the mean disease control was 68.6%. As a group, experimental antibiotics provided the best fire blight control with mean effect sizes ranging from 59.7 to 61.7%. Among the biological controls, the best control was noted for treatments combining the antibiotic streptomycin with a product based on Pantoea agglomerans (55.0% mean disease reduction) or Bacillus subtilis (53.9%). Mean disease control was 31.9, 25.7, and 22.6%, respectively, for products based on B. subtilis, Pantoea agglomerans, and Pseudomonas fluorescens without an antibiotic, suggesting that the higher efficacy of the combination treatments was due to the antibiotic. Among the plant defense-activating products, prohexadione calcium had the highest and most consistent effect size (50.7% control), while other products provided modest mean disease control of between 6.1 and 25.8%. Percent control values were significantly moderated by study location and cultivar used in the study, and were smaller, but more variable, when products were tested under high disease intensity compared with low disease intensity. Results indicate that wide-scale use of biological control and plant defense-activating products in the eastern United States is likely to remain low.
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Affiliation(s)
- H K Ngugi
- Department of Plant Pathology, Pennsylvania State University, Biglerville, PA, USA.
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39
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Woriedh M, Hauber I, Martinez-Rocha AL, Voigt C, Maier FJ, Schröder M, Meier C, Hauber J, Schäfer W. Preventing Fusarium head blight of wheat and cob rot of maize by inhibition of fungal deoxyhypusine synthase. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2011; 24:619-27. [PMID: 21463208 DOI: 10.1094/mpmi-03-10-0068] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Upon posttranslational activation, the eukaryotic initiation factor-5A (eIF-5A) transports a subset of mRNAs out of the nucleus to the ribosomes for translation. Activation of the protein is an evolutionary highly conserved process that is unique to eIF-5A, the conversion of a lysine to a hypusine. Instrumental for the synthesis of hypusine is the first of two enzymatic reactions mediated by deoxyhypusine synthase (DHS). We show that DHS of wheat and the pathogenic fungus Fusarium graminearum, which causes one of the most destructive crop diseases worldwide, are transcriptionally upregulated during their pathogenic interaction. Although DHS of wheat, fungus, and human can be equally inhibited by the inhibitor CNI-1493 in vitro, application during infection of wheat and maize flowers results in strong inhibition of the pathogen without interference with kernel development. Our studies provide a novel strategy to selectively inhibit fungal growth without affecting plant growth. We identified fungal DHS as a target for the development of new inhibitors, for which CNI-1493 may serve as a lead substance.
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Affiliation(s)
- Mayada Woriedh
- Department of Molecular Phytopathology and Genetics, Biocenter Klein Flottbek, University of Hamburg, Ohnhorststrasse 18, D-22609 Hamburg, Germany
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40
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Madden LV, Paul PA. Meta-analysis for evidence synthesis in plant pathology: an overview. PHYTOPATHOLOGY 2011; 101:16-30. [PMID: 21142781 DOI: 10.1094/phyto-03-10-0069] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Meta-analysis is the analysis of the results of multiple studies, which is typically performed in order to synthesize evidence from many possible sources in a formal probabilistic manner. In a simple sense, the outcome of each study becomes a single observation in the meta-analysis of all available studies. The methodology was developed originally in the social sciences by Smith, Glass, Rosenthal, Hunter, and Schmidt, based on earlier pioneering contributions in statistics by Fisher, Pearson, Yates, and Cochran, but this approach to research synthesis has now been embraced within many scientific disciplines. However, only a handful of articles have been published in plant pathology and related fields utilizing meta-analysis. After reviewing basic concepts and approaches, methods for estimating parameters and interpreting results are shown. The advantages of meta-analysis are presented in terms of prediction and risk analysis, and the high statistical power that can be achieved for detecting significant effects of treatments or significant relationships between variables. Based on power considerations, the fallacy of naïve counting of P values in a narrative review is demonstrated. Although there are many advantages to meta-analysis, results can be biased if the analysis is based on a nonrepresentative sample of study outcomes. Therefore, novel approaches for characterizing the upper bound on the bias are discussed, in order to show the robustness of meta-analysis to possible violation of assumptions.
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Affiliation(s)
- L V Madden
- Department of Plant Pathology, Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691, USA.
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41
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Mila AL, Ngugi HK. A Bayesian approach to meta-analysis of plant pathology studies. PHYTOPATHOLOGY 2011; 101:42-51. [PMID: 20822433 DOI: 10.1094/phyto-03-10-0070] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Bayesian statistical methods are used for meta-analysis in many disciplines, including medicine, molecular biology, and engineering, but have not yet been applied for quantitative synthesis of plant pathology studies. In this paper, we illustrate the key concepts of Bayesian statistics and outline the differences between Bayesian and classical (frequentist) methods in the way parameters describing population attributes are considered. We then describe a Bayesian approach to meta-analysis and present a plant pathological example based on studies evaluating the efficacy of plant protection products that induce systemic acquired resistance for the management of fire blight of apple. In a simple random-effects model assuming a normal distribution of effect sizes and no prior information (i.e., a noninformative prior), the results of the Bayesian meta-analysis are similar to those obtained with classical methods. Implementing the same model with a Student's t distribution and a noninformative prior for the effect sizes, instead of a normal distribution, yields similar results for all but acibenzolar-S-methyl (Actigard) which was evaluated only in seven studies in this example. Whereas both the classical (P = 0.28) and the Bayesian analysis with a noninformative prior (95% credibility interval [CRI] for the log response ratio: -0.63 to 0.08) indicate a nonsignificant effect for Actigard, specifying a t distribution resulted in a significant, albeit variable, effect for this product (CRI: -0.73 to -0.10). These results confirm the sensitivity of the analytical outcome (i.e., the posterior distribution) to the choice of prior in Bayesian meta-analyses involving a limited number of studies. We review some pertinent literature on more advanced topics, including modeling of among-study heterogeneity, publication bias, analyses involving a limited number of studies, and methods for dealing with missing data, and show how these issues can be approached in a Bayesian framework. Bayesian meta-analysis can readily include information not easily incorporated in classical methods, and allow for a full evaluation of competing models. Given the power and flexibility of Bayesian methods, we expect them to become widely adopted for meta-analysis of plant pathology studies.
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Affiliation(s)
- A L Mila
- Department of Plant Pathology, North Carolina State University, Campus Box 7405, Raleigh 27606, USA
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Ngugi HK, Esker PD, Scherm H. Meta-analysis to determine the effects of plant disease management measures: review and case studies on soybean and apple. PHYTOPATHOLOGY 2011; 101:31-41. [PMID: 20854109 DOI: 10.1094/phyto-03-10-0068] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The continuing exponential increase in scientific knowledge, the growing availability of large databases containing raw or partially annotated information, and the increased need to document impacts of large-scale research and funding programs provide a great incentive for integrating and adding value to previously published (or unpublished) research through quantitative synthesis. Meta-analysis has become the standard for quantitative evidence synthesis in many disciplines, offering a broadly accepted and statistically powerful framework for estimating the magnitude, consistency, and homogeneity of the effect of interest across studies. Here, we review previous and current uses of meta-analysis in plant pathology with a focus on applications in epidemiology and disease management. About a dozen formal meta-analyses have been published in the plant pathological literature in the past decade, and several more are currently in progress. Three broad research questions have been addressed, the most common being the comparative efficacy of chemical treatments for managing disease and reducing yield loss across environments. The second most common application has been the quantification of relationships between disease intensity and yield, or between different measures of disease, across studies. Lastly, meta-analysis has been applied to assess factors affecting pathogen-biocontrol agent interactions or the effectiveness of biological control of plant disease or weeds. In recent years, fixed-effects meta-analysis has been largely replaced by random- (or mixed-) effects analysis owing to the statistical benefits associated with the latter and the wider availability of computer software to conduct these analyses. Another recent trend has been the more common use of multivariate meta-analysis or meta-regression to analyze the impacts of study-level independent variables (moderator variables) on the response of interest. The application of meta-analysis to practical problems in epidemiology and disease management is illustrated with case studies from our work on Phakopsora pachyrhizi on soybean and Erwinia amylovora on apple. We show that although meta-analyses are often used to corroborate and validate general conclusions drawn from more traditional, qualitative reviews, they can also reveal new patterns and interpretations not obvious from individual studies.
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Affiliation(s)
- Henry K Ngugi
- Department of Plant Pathology, Pennsylvania State University Fruit Research & Extension Center, Biglerville 17307, USA
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Ojiambo PS, Paul PA, Holmes GJ. A quantitative review of fungicide efficacy for managing downy mildew in cucurbits. PHYTOPATHOLOGY 2010; 100:1066-76. [PMID: 20839942 DOI: 10.1094/phyto-12-09-0348] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
A meta-analysis of the effect of fungicides on cucurbit downy mildew was conducted using data previously published in Fungicide & Nematicide Tests and Plant Disease Management Reports from 2000 to 2008. Standardized mean effect size (the difference in disease intensity expressed in standard deviation units between the fungicide treatment and its corresponding untreated control) was calculated for each of the 105 field studies evaluating the effects of fungicides on cucurbit downy mildew. Fixed- and random-effects meta-analyses were performed on the log-transformed standardized mean effect sizes to estimate the overall mean effect size (L+), and to determine the variability in the effect size among studies. Fungicides led to a significant (P<0.001) reduction in disease with an L+ value of 1.198, indicating that, overall, fungicides were highly effective against cucurbit downy mildew. Fixed- and random-effects meta-analyses were then conducted to determine the effects of moderator variables on L+. The fixed-effects model resulted in narrower 95% confidence intervals and generally lower estimates of moderator subgroup mean effect size (L) than the random-effects models. Fungicide efficacy was significantly (P<0.001) greater in cucumber, with L being 26.5% higher in cucumber than in other cucurbits. Year of study, number of sprays, and disease pressure in the control significantly (P<0.001) affected L. Fungicide efficacy was significantly lower during the 2004-05 season than prior to or after the 2004-05 season. Studies in which disease pressure was moderate had a significantly higher L than studies with either low or high disease pressure. Fungicide efficacy was ≥22% in studies that received 5 to 6 sprays than in studies that received 1 to 4 or >6 sprays. Fungicide products led to a significant (P<0.001) reduction in disease, although there was substantial between-study variability. The pyridinylmethyl-benzamide group of fungicides (fluopicolide) was the most effective, followed by the carbamate (propamocarb) and quinone inside inhibitors (cyazofamid) group of fungicides, while the carboxylic acid amide group (mandipropamid and dimethomorph) was the least effective. A combination of protectant and systemic fungicides resulted in a proportional increase in L compared with sole application of either protectant or systemic fungicides.
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Affiliation(s)
- P S Ojiambo
- Department of Plant Pathology, North Carolina State University, Raleigh, NC 27695, USA.
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Bernhoft A, Clasen PE, Kristoffersen AB, Torp M. Less Fusarium infestation and mycotoxin contamination in organic than in conventional cereals. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2010; 27:842-52. [PMID: 20425661 DOI: 10.1080/19440041003645761] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
A total of 602 samples of cereals, consisting of organically and conventionally produced barley, oats and wheat, were collected at harvest during 2002-2004 in Norway. Organic and conventional cereals were sampled in comparable numbers regarding cereal species, localisation and harvest time, and analysed for Fusarium mould and mycotoxins. Fusarium infestation and mycotoxin content were dependent on cereal species and varied year-by-year. However, in all cereal species, Fusarium infestation and levels of important mycotoxins were significantly lower when grown organically than conventionally. Concerning the most toxic trichothecenes, HT-2 and T-2 toxin, lower concentrations were found in organic oats and barley. Wheat was not contaminated by HT-2 and T-2, but lower concentrations of deoxynivalenol (DON) and moniliformin (MON) were found when organically produced. For mycotoxins considered to constitute the main risk to humans and animals in Norwegian cereals, i.e. HT-2 in oats and DON in oats and wheat, the median figures (mean levels in brackets) were as follows: HT-2 in organic and conventional oats were <20 (80) and 62 (117) microg/kg, DON in organic and conventional oats were 24 (114) and 36 (426) microg/kg, and DON in organic and conventional wheat were 29 (86) and 51 (170) microg/kg, respectively. Concentrations of HT-2 and T-2 in the samples were strongly correlated (r = 0.94). Other mycotoxins did not show a significant correlation to each other. Both HT-2 and T-2 concentrations were significantly correlated with infestation of F. langsethiae (r = 0.65 and r = 0.60, respectively). Concentrations of DON were significantly correlated with F. graminearum infestation (r = 0.61). Furthermore, nivalenol (NIV) was significantly correlated with infestation of F. poae (r = 0.55) and MON with F. avenaceum (r = 0.37). As lower Fusarium infestation and mycotoxin levels were found in organic cereals, factors related to agricultural practice may reduce the risk of contamination with Fusarium mycotoxins. Studies of these issues will be presented separately.
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Affiliation(s)
- A Bernhoft
- National Veterinary Institute, N-0106 Oslo, Norway.
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Paul PA, McMullen MP, Hershman DE, Madden LV. Meta-analysis of the effects of triazole-based fungicides on wheat yield and test weight as influenced by Fusarium head blight intensity. PHYTOPATHOLOGY 2010; 100:160-171. [PMID: 20055650 DOI: 10.1094/phyto-100-2-0160] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
ABSTRACT Multivariate random-effects meta-analyses were conducted on 12 years of data from 14 U.S. states to determine the mean yield and test-weight responses of wheat to treatment with propiconazole, prothioconazole, tebuconazole, metconazole, and prothioconazole+tebuconazole. All fungicides led to a significant increase in mean yield and test weight relative to the check (D; P < 0.001). Metconazole resulted in the highest overall yield increase, with a D of 450 kg/ha, followed by prothioconazole+ tebuconazole (444.5 kg/ha), prothioconazole (419.1 kg/ha), tebuconazole (272.6 kg/ha), and propiconazole (199.6 kg/ha). Metconazole, prothioconazole+tebuconazole, and prothioconazole also resulted in the highest increases in test weight, with D values of 17.4 to 19.4 kg/m(3), respectively. On a relative scale, the best three fungicides resulted in an overall 13.8 to 15.0% increase in yield but only a 2.5 to 2.8% increase in test weight. Except for prothioconazole+tebuconazole, wheat type significantly affected the yield response to treatment; depending on the fungicide, D was 110.0 to 163.7 kg/ha higher in spring than in soft-red winter wheat. Fusarium head blight (FHB) disease index (field or plot-level severity) in the untreated check plots, a measure of the risk of disease development in a study, had a significant effect on the yield response to treatment, in that D increased with increasing FHB index. The probability was estimated that fungicide treatment in a randomly selected study will result in a positive yield increase (p(+)) and increases of at least 250 and 500 kg/ha (p(250) and p(500), respectively). For the three most effective fungicide treatments (metconazole, prothioconazole+tebuconazole, and prothioconazole) at the higher selected FHB index, p(+) was very large (e.g., >/=0.99 for both wheat types) but p(500) was considerably lower (e.g., 0.78 to 0.92 for spring and 0.54 to 0.68 for soft-red winter wheat); at the lower FHB index, p(500) for the same three fungicides was 0.34 to 0.36 for spring and only 0.09 to 0.23 for soft-red winter wheat.
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Affiliation(s)
- P A Paul
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691, USA
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Madden LV, Paul PA. Assessing heterogeneity in the relationship between wheat yield and Fusarium head blight intensity using random-coefficient mixed models. PHYTOPATHOLOGY 2009; 99:850-860. [PMID: 19522583 DOI: 10.1094/phyto-99-7-0850] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Seventy-seven studies reporting Fusarium head blight disease index (Y; mean percentage of diseased spikelets per spike) and wheat yield (W; MT/ha) were analyzed to determine the relationship between W and Y, and to assess the degree of variation for the relationship among studies. A linear random-coefficient model-comprising a population-average intercept and slope, a random residual term, and random effects of study on the intercept and slope (best linear unbiased predictors; BLUPs)-was successfully fitted to the data using maximum likelihood. From the predicted random effects, study-specific intercepts and slopes were obtained, and both population-average and subject-specific predictions of yield were determined. The estimated population-average intercept (expected yield when disease symptoms were not present) was 4.10 MT/ha, and the population-average slope was 0.038 MT/ha per unit increase of disease index. Wheat class had a significant effect on the intercept but not on the slope, with soft-red winter wheat having, on average, 0.85 MT/ha higher yield than spring wheat. Based on the estimates of the among-study variances, there was high variation in the effects of study on the intercept, but substantially lower variation in the effects of study on the slope. Thus, although one cannot predict with accuracy the actual wheat yield in a field or plot based on disease index using population-average results, one can predict with accuracy the decline in yield at a given level of disease index using the population-average slope. Through the modeling results, predicted relative yield (as a percentage of yield when disease is not present) can be determined, as well as predicted disease index at which a prespecified level of yield (or yield loss) is expected to occur. The predicted reduction in yield on a percentage scale was greater for spring than for soft-red winter wheat, on average, because of the lower estimated intercept in absolute units for spring wheat.
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Affiliation(s)
- L V Madden
- Department of Plant Pathology, The Ohio State University, Wooster, OH 44691, USA.
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Xu X, Nicholson P. Community ecology of fungal pathogens causing wheat head blight. ANNUAL REVIEW OF PHYTOPATHOLOGY 2009; 47:83-103. [PMID: 19385728 DOI: 10.1146/annurev-phyto-080508-081737] [Citation(s) in RCA: 152] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Research on the pathogen components involved in Fusarium head blight (FHB) along with the effects of their interactions on disease development and mycotoxin accumulation is reviewed. The fungal components within the FHB complex differ significantly in different environments. Individual species may respond differently to, and be differentially influenced by, particular disease control measures. Almost all published co-inoculation studies on wheat spikes or grains show that competitive interactions among FHB pathogens are the rule when fungal/disease development is considered. However, the fungi with the competitive advantage do not usually gain any advantage from the presence of other weaker competing fungi. Total mycotoxin production in mixed inoculations may decrease, increase, or remain unchanged compared with single-isolate inoculations, depending on the fungal species concerned and environmental conditions. A few recent studies, where each individual fungal component was quantified using molecular methods, suggest that mycotoxin productivity in mixed inoculations generally increases.
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Affiliation(s)
- Xiangming Xu
- College of Plant Protection, NorthWest A&F University, Yangling, P.R. China
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Foroud NA, Eudes F. Trichothecenes in cereal grains. Int J Mol Sci 2009; 10:147-173. [PMID: 19333439 PMCID: PMC2662451 DOI: 10.3390/ijms10010147] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Revised: 12/16/2008] [Accepted: 01/05/2009] [Indexed: 12/22/2022] Open
Abstract
Trichothecenes are sesquiterpenoid mycotoxins associated with fusarium head blight (FHB) of cereals, with worldwide economic and health impacts. While various management strategies have been proposed to reduce the mycotoxin risk, breeding towards FHB-resistance appears to be the most effective means to manage the disease, and reduce trichothecene contamination of cereal-based food products. This review provides a brief summary of the trichothecene synthesis in Fusarium species, their toxicity in plants and humans, followed by the current methods of screening and breeding for resistance to FHB and trichothecene accumulation.
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Affiliation(s)
- Nora A. Foroud
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, 5403 1 Avenue South, Lethbridge, AB, Canada T1J 4B1. E-Mail:
- Michael Smith Laboratories, The University of British Columbia, #301 - 2185 East Mall, Vancouver, B.C., Canada V6T 1Z4
| | - François Eudes
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, 5403 1 Avenue South, Lethbridge, AB, Canada T1J 4B1. E-Mail:
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Hollingsworth CR, Motteberg CD, Wiersma JV, Atkinson LM. Agronomic and Economic Responses of Spring Wheat to Management of Fusarium Head Blight. PLANT DISEASE 2008; 92:1339-1348. [PMID: 30769453 DOI: 10.1094/pdis-92-9-1339] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Spring wheat (Triticum aestivum) crop losses in the Red River Valley of Minnesota and North Dakota caused by Fusarium head blight (FHB) epidemics incited by Fusarium graminearum are common. Fungicide application is often recommended when environments promote disease development but benefits have not been fully evaluated when environment, cultivar resistance, and economic outcome are considered. Agronomic and economic characters were determined for cultivars with various resistance levels when treated with no fungicide; propiconazole at 63 g active ingredient (a.i.)/ha applied at Feekes growth stage (FGS) 2, tebuconazole at 126 g a.i./ha applied at FGS 10.51, or propiconazole at 63 g a.i./ha applied at FGS 2 followed by tebuconazole at 126 g a.i./ha applied at FGS 10.51. Revenue returned from FHB moderately susceptible (MS) cultivars was 8% greater than moderately resistant (MR) cultivars in low-disease environs but differences were not significant when disease was moderate. Deoxynivalenol accumulation in grain of MS and MR cultivars was unchanged by fungicide treatment. MS cultivars were economically more adventitious to grow than MR cultivars in both disease environments.
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Affiliation(s)
- C R Hollingsworth
- University of Minnesota, Northwest Research and Outreach Center and Department of Plant Pathology
| | - C D Motteberg
- University of Minnesota, Northwest Research and Outreach Center and Department of Plant Pathology
| | - J V Wiersma
- University of Minnesota, Northwest Research and Outreach Center, Crookston, MN 56716
| | - L M Atkinson
- University of North Dakota, Department of Earth System Science and Policy, Northern Great Plains Center for People & Environment, Grand Forks, ND 58202-9011
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Paul PA, Lipps PE, Hershman DE, McMullen MP, Draper MA, Madden LV. Efficacy of triazole-based fungicides for fusarium head blight and deoxynivalenol control in wheat: a multivariate meta-analysis. PHYTOPATHOLOGY 2008; 98:999-1011. [PMID: 18943738 DOI: 10.1094/phyto-98-9-0999] [Citation(s) in RCA: 138] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The effects of propiconazole, prothioconazole, tebuconazole, metconazole, and prothioconazole+tebuconazole (as a tank mix or a formulated premix) on the control of Fusarium head blight index (IND; field or plot-level disease severity) and deoxynivalenol (DON) in wheat were determined. A multivariate random-effects meta-analytical model was fitted to the log-transformed treatment means from over 100 uniform fungicide studies across 11 years and 14 states, and the mean log ratio (relative to the untreated check or tebuconazole mean) was determined as the overall effect size for quantifying fungicide efficacy. Mean log ratios were then transformed to estimate mean percent reduction in IND and DON relative to the untreated check (percent control: C(IND) and C(DON)) and relative to tebuconazole. All fungicides led to a significant reduction in IND and DON (P < 0.001), although there was substantial between-study variability. Prothioconazole+tebuconazole was the most effective fungicide for IND, with a C(IND) of 52%, followed by metconazole (50%), prothioconazole (48%), tebuconazole (40%), and propiconazole (32%). For DON, metconazole was the most effective treatment, with a [Formula: see text](DON) of 45%; prothioconazole+tebuconazole and prothioconazole showed similar efficacy, with C(DON) values of 42 and 43%, respectively; tebuconazole and propiconazole were the least effective, with C(DON) values of 23 and 12%, respectively. All fungicides, with the exception of propiconazole, were significantly more effective than tebuconazole for control of both IND and DON (P < 0.001). Relative to tebuconazole, prothioconazole, metconazole, and tebuconzole+prothioconzole reduced disease index a further 14 to 20% and DON a further 25 to 29%. In general, fungicide efficacy was significantly higher for spring wheat than for soft winter wheat studies; depending on the fungicide, the difference in percent control between spring and soft winter wheat was 5 to 20% for C(IND) and 7 to 16% for C(DON). Based on the mean log ratios and between-study variances, the probability that IND or DON in a treated plot from a randomly selected study was lower than that in the check by a fixed margin was determined, which confirmed the superior efficacy of prothioconazole, metconazole, and tebuconzole+prothioconzole for Fusarium head blight disease and toxin control.
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Affiliation(s)
- P A Paul
- Department of Plant Pathology, The Ohio State University, Ohio Agricultural Research and Development Center, Wooster 44691, USA
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