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Song C, Yang X, He L, Wang W, Wu K. Control Efficacy of the Bt Maize Event DBN3601T Expressing Cry1Ab and Vip3Aa Proteins against Beet Armyworm, Spodoptera exigua (Hübner), in China. PLANTS (BASEL, SWITZERLAND) 2024; 13:1933. [PMID: 39065460 PMCID: PMC11281214 DOI: 10.3390/plants13141933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2024] [Revised: 07/01/2024] [Accepted: 07/12/2024] [Indexed: 07/28/2024]
Abstract
The beet armyworm, Spodoptera exigua (Hübner), is a major pest of maize, cotton, soybean, and many other crops globally. Despite the widespread deployment of Bt transgenic maize for pest control worldwide, the efficacy of Bt lepidopteran-resistant transgenic maize in managing S. exigua remains rarely studied. In this study, we quantified the expression level of pyramided Cry1Ab and Vip3Aa toxins in Bt maize (event DBN3601T) and evaluated their control efficiency against S. exigua under both laboratory and field conditions. The enzyme-linked immunosorbent assay (ELISA) results showed that the expression levels of Cry1Ab and Vip3Aa proteins in DBN3601T maize tissues followed a decreasing order as follows: V5-leaf > V8-leaf > VT-tassel > R2-kernel > R1-silk. Diet-overlay assay results showed that the LC50 values of Cry1Ab and Vip3Aa proteins against S. exigua larvae were 11.66 ng/cm2 and 27.74 ng/cm2, respectively, with corresponding GIC50 values at 1.59 ng/cm2 and 7.93 ng/cm2. Bioassay using various tissues of the DBN3601T maize indicated that after 7 days of infestation, mortality rates of neonates and third-instar larvae ranged from 86% to 100% and 58% to 100%, respectively. Mortality was highest on V5 and V8 leaves, followed by R2-kernel, VT-tassel, and R1-silk. Field trials demonstrated that DBN3601T maize exhibited significantly lower larval density, damage rate, and leaf damage score compared to non-Bt maize. Field cage trial showed that the control efficacy of DBN3601T maize at the vegetative stage could reach 98%. These findings provide a theoretical basis for utilizing Bt transgenic maize to enhance the sustainable management of S. exigua in Asia.
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Affiliation(s)
- Cheng Song
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou 350002, China;
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (X.Y.); (W.W.)
| | - Xianming Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (X.Y.); (W.W.)
| | - Limei He
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu 610299, China;
| | - Wenhui Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (X.Y.); (W.W.)
- Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Kongming Wu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (X.Y.); (W.W.)
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Liu Y, Zhang L, Cai X, Rutikanga A, Qiu B, Hou Y. The Diversity of Wolbachia and Other Bacterial Symbionts in Spodoptera frugiperda. INSECTS 2024; 15:217. [PMID: 38667347 PMCID: PMC11050099 DOI: 10.3390/insects15040217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 03/16/2024] [Accepted: 03/18/2024] [Indexed: 04/28/2024]
Abstract
Bacterial symbionts associated with insects can be crucial in insect nutrition, metabolism, immune responses, development, and reproduction. However, the bacterial symbionts of the fall armyworm Spodoptera frugiperda remain unclear. S. frugiperda is an invasive polyphagous pest that severely damages many crops, particularly maize and wheat. Here, we investigated the infection, composition, abundance, and diversity of bacterial symbionts, especially Wolbachia, in different tissues of S. frugiperda female adults. The infection prevalence frequencies of Wolbachia in five provinces of China, namely Pu'er, Yunnan; Nanning, Guangxi; Sanya, Hainan; Yunfu, Guangdong; and Nanping, Fujian, were assessed. The results indicated that Proteobacteria, Firmicutes, and Bacteroidetes were the three most dominant bacterial phyla in S. frugiperda adults. At the genus level, the abundant microbiota, which included Enterobacter and Enterococcus, varied in abundance between tissues of S. frugiperda. Wolbachia was found in the ovaries and salivary glands of S. frugiperda adults, and was present in 33.33% of the Pu'er, Yunnan, 23.33% of the Nanning, Guangxi, and 13.33% of the Sanya, Hainan populations, but Wolbachia was absent in the Yunfu, Guangdong and Nanping, Fujian populations. Further phylogenetic analyses revealed that all of the Wolbachia strains from the different S. frugiperda populations belonged to the supergroup B and were named the wFru strain. Since there were Wolbachia strains inducing cytoplasmic incompatibility in supergroup B, these findings may provide a foundation for developing potential biocontrol techniques against S. frugiperda.
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Affiliation(s)
- Yuan Liu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (Y.L.)
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
- Engineering Research Center of Biotechnology for Active Substances, Ministry of Education, Chongqing Normal University, Chongqing 401331, China
| | - Lina Zhang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (Y.L.)
| | - Xiangyun Cai
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (Y.L.)
| | - Alexandre Rutikanga
- College of Agriculture and Animal Husbandry, University of Rwanda, Kigali 999051, Rwanda
| | - Baoli Qiu
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
- Engineering Research Center of Biotechnology for Active Substances, Ministry of Education, Chongqing Normal University, Chongqing 401331, China
| | - Youming Hou
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (Y.L.)
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Rodriguez-Chalarca J, Valencia SJ, Rivas-Cano A, Santos-González F, Romero DP. Impact of Bt corn expressing Bacillus thuringiensis Berliner insecticidal proteins on the growth and survival of Spodoptera frugiperda larvae in Colombia. FRONTIERS IN INSECT SCIENCE 2024; 4:1268092. [PMID: 38469336 PMCID: PMC10926427 DOI: 10.3389/finsc.2024.1268092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 01/30/2024] [Indexed: 03/13/2024]
Abstract
Bioassays were conducted under controlled conditions to determine the response of Spodoptera frugiperda (J. E. Smith) larvae fed with corn materials expressing Bacillus thuringiensis (Bt) insecticidal endotoxins: (1) VT Double Pro® (VT2P) expressing Cry1A.105-Cry2Ab2 proteins and (2) VT Triple Pro® (VT3P) expressing Cry1A.105-Cry2Ab2-Cry3Bb1 proteins. The parameters assessed were: (i) mortality rate, and (ii) growth inhibition (GI) with respect to the control. To conduct this study, larvae were collected from commercial non-Bt corn fields, in four agricultural sub-regions in Colombia, between 2018 and 2020. Fifty-two populations were assessed from the field and neonate larvae from each of the populations were used for the bioassays. The study found that mortality rates in the regions for larvae fed with VT2P corn ranged from 95.1 to 100.0%, with a growth inhibition (%GI) higher than 76.0%. Similarly, mortality rate for larvae fed with VT3P corn were between 91.4 and 100.0%, with a %GI above 74.0%. The population collected in Agua Blanca (Espinal, Tolima; Colombia) in 2020, showed the lowest mortality rate of 53.2% and a %GI of 73.5%, with respect to the control. The population that exhibited the lowest %GI was collected in 2018 in Agua Blanca (Espinal, Tolima, Colombia) with a 30.2%, growth inhibition, with respect to the control. In recent years, the use of plant tissue to monitor susceptibility to fall armyworm has proven to be useful in the resistance management program for corn in Colombia determining that the FAW populations are still susceptible to Bt proteins contained in VT2P and VT3P.
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Affiliation(s)
- Jairo Rodriguez-Chalarca
- Crops for Nutrition and Health, The Alliance of Bioversity International and Centro Internacional de Agricultura Tropical (International Center for Tropical Agriculture), Palmira, Colombia
| | - Sandra J. Valencia
- Crops for Nutrition and Health, The Alliance of Bioversity International and Centro Internacional de Agricultura Tropical (International Center for Tropical Agriculture), Palmira, Colombia
| | - Alejandra Rivas-Cano
- Crops for Nutrition and Health, The Alliance of Bioversity International and Centro Internacional de Agricultura Tropical (International Center for Tropical Agriculture), Palmira, Colombia
- Universidad Nacional de Colombia Sede Palmira, Palmira, Colombia
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Chen S, Wang W, Kang G, Yang X, Wu K. Toxic Effects of Bt-(Cry1Ab+Vip3Aa) Maize on Storage Pest Paralipsa gularis (Zeller). Toxins (Basel) 2024; 16:92. [PMID: 38393170 PMCID: PMC10892971 DOI: 10.3390/toxins16020092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Revised: 01/25/2024] [Accepted: 02/05/2024] [Indexed: 02/25/2024] Open
Abstract
Paralipsa gularis (Zeller) is a storage pest; however, in recent years it has evolved into a considerable maize pest during the late growth stage in the border region between China and other Southeast Asian countries. Bt transgenic insect-resistant maize is an effective measure in controlling a wide range of lepidopteran pests, but there is a lack of research on the toxic effects of storage pests. We tested the toxicity of Bt-Cry1Ab, Vip3Aa, and their complex proteins against P. gularis via bioassay and investigated the efficiency of Bt-(Cry1Ab+Vip3Aa) maize in controlling P. gularis during the late growth stage of maize in the period 2022-2023. The bioassay results show that the susceptibilities of P. gularis to the two Bt proteins and their complex proteins were significantly different. The LC50 values of DBNCry1Ab ("DBN9936" event), DBNVip3Aa ("DBN9501" event), DBN Cry1Ab+Vip3Aa ("DBN3601T" event), and Syngenta Cry1Ab+Vip3Aa ("Bt11" event × "MIR162" event) were 0.038 μg/g, 0.114 μg/g, 0.110 μg/g, and 0.147 μg/g, and the GIC50 values were 0.014 μg/g, 0.073 μg/g, 0.027 μg/g, and 0.026 μg/g, respectively. Determination of the expression content of the insecticidal protein in different tissues of Bt-(Cry1Ab+Vip3Aa) maize shows that the total Bt protein content in different tissues was in the following order: stalk > bract > cob > kernel. However, the bioassay results show that the mortalities of P. gularis feeding on Bt-(Cry1Ab+Vip3Aa) maize in different tissues at different growth stages were all above 93.00%. The field trial indicates that the occurrence density of larvae and plant damage rate for conventional maize were 422.10 individuals/100 plants and 94.40%, respectively, whereas no larvae were found on Bt-(Cry1Ab+Vip3Aa) maize. In summary, this study implies that Bt-(Cry1Ab+Vip3Aa) maize has a high potential for control of P. gularis, providing a new technical measure for the management of the pest.
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Affiliation(s)
- Shuang Chen
- College of Plant Protection, Henan Agricultural University, Zhengzhou 450002, China;
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (G.K.); (X.Y.)
| | - Wenhui Wang
- Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China;
| | - Guodong Kang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (G.K.); (X.Y.)
| | - Xianming Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (G.K.); (X.Y.)
| | - Kongming Wu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (G.K.); (X.Y.)
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Trisyono YA, Aryuwandari VEF, Rahayu T, Martinelli S, Head GP, Parimi S, Camacho LR. Baseline Susceptibility of the Field Populations of Ostrinia furnacalis in Indonesia to the Proteins Cry1A.105 and Cry2Ab2 of Bacillus thuringiensis. Toxins (Basel) 2023; 15:602. [PMID: 37888633 PMCID: PMC10610637 DOI: 10.3390/toxins15100602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 10/06/2023] [Accepted: 10/06/2023] [Indexed: 10/28/2023] Open
Abstract
Genetically modified MON 89034 corn (Zea mays L.) expressing Bacillus thuringiensis (Bt) insecticidal proteins, viz. Cry1A.105 and Cry2Ab2, is a biotechnological option being considered for the management of the major corn pest in Indonesia, the Asian corn borer (Ostrinia furnacalis (Guenée) (Lepidoptera: Crambidae)). As a part of a proactive resistance-management program for MON 89034 corn in Indonesia, we assessed the baseline susceptibility of field-collected populations of O. furnacalis to Cry1A.105 and Cry2Ab2 proteins. Dose-response bioassays using the diet-dipping method indicated that the lethal concentration (LC50) values of Cry1A.105 and Cry2Ab2 in 24 different field populations of O. furnacalis ranged from 0.006 to 0.401 µg/mL and from 0.044 to 4.490 µg/mL, respectively, while the LC95 values ranged from 0.069 to 15.233 µg/mL for Cry1A.105 and from 3.320 to 277.584 µg/mL for Cry2Ab2. The relative resistance ratios comparing the most tolerant field populations and an unselected laboratory population were 6.0 for Cry1A.105 and 2.0 for Cry2Ab2 based on their LC50 values. Some field populations were more susceptible to both proteins than the unselected laboratory population. The LC99 and its 95% fiducial limits across the field populations were calculated and proposed as candidate diagnostic concentrations. These data provide a basis for resistance monitoring in Bt Corn and further support building resistance-management strategies in Indonesia.
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Affiliation(s)
- Y. Andi Trisyono
- Department of Plant Protection, Faculty of Agriculture, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
| | - Valentina E. F. Aryuwandari
- Department of Plant Protection, Faculty of Agriculture, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
| | - Teguh Rahayu
- Department of Plant Protection, Faculty of Agriculture, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
| | - Samuel Martinelli
- Regulatory Science, Bayer Crop Science US, Chesterfield, MO 63017, USA
| | - Graham P. Head
- Regulatory Science, Bayer Crop Science US, Chesterfield, MO 63017, USA
| | | | - Luis R. Camacho
- Bayer (South East Asia) Pte Ltd., 2 Tanjong Katong Road #07-01, Paya Lebar Quarter 3, Singapore 437161, Singapore
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Apirajkamol NB, Hogarty TM, Mainali B, Taylor PW, Walsh TK, Tay WT. Virulence of Beauveria sp. and Metarhizium sp. fungi towards fall armyworm (Spodoptera frugiperda). Arch Microbiol 2023; 205:328. [PMID: 37676308 PMCID: PMC10495518 DOI: 10.1007/s00203-023-03669-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 08/16/2023] [Accepted: 08/28/2023] [Indexed: 09/08/2023]
Abstract
The development of effective pest management strategies for Spodoptera frugiperda is a high priority for crop protection across its invasive ranges. Here, we examined six Beauveria and five Metarhizium fungal isolates against this pest. Two Beauveria isolates (B-0571, B-1311) induced high mortality toward 3rd and 6th instar caterpillars and adults. For B-0571 mortality was 82.81 ± 5.75%, 61.46 ± 6.83%, and 93.75 ± 3.61%, and 73.72 ± 2.51%, 71.88 ± 5.41%, and 97.92 ± 2.08% for B-1311, with deaths in caterpillars largely occurring under 24 h (3rd instar control 0.74 ± 0.33%, B-0571 73.96 ± 7.85% and B-1311 62.08 ± 3.67%; 6th instar control 0%, B-0571 66.67% ± 11.02% and B-1311 62.5% ± 9.55%). Infection from both Beauveria isolates fully prevented reproduction in surviving S. frugiperda females. In contrast, all five Metarhizium isolates tested and the remaining four Beauveria isolates exhibited lower virulence. The discovery of two highly virulent Beauveria fungal isolates to S. frugiperda opens avenues to develop novel biological control tools against this highly invasive pest.
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Affiliation(s)
- Nonthakorn Beatrice Apirajkamol
- Applied BioSciences, Macquarie University, Sydney, NSW, 2109, Australia.
- Black Mountain Laboratories, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT, 2601, Australia.
| | - Timothy Michael Hogarty
- Black Mountain Laboratories, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT, 2601, Australia
| | - Bishwo Mainali
- Applied BioSciences, Macquarie University, Sydney, NSW, 2109, Australia
| | | | - Thomas Kieran Walsh
- Applied BioSciences, Macquarie University, Sydney, NSW, 2109, Australia
- Black Mountain Laboratories, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT, 2601, Australia
| | - Wee Tek Tay
- Applied BioSciences, Macquarie University, Sydney, NSW, 2109, Australia
- Black Mountain Laboratories, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT, 2601, Australia
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Song Y, Yang X, Li H, Wu K. The invasive Spodoptera frugiperda (J.E. Smith) has displaced Ostrinia furnacalis (Guenée) as the dominant maize pest in the border area of southwestern China. PEST MANAGEMENT SCIENCE 2023; 79:3354-3363. [PMID: 37132322 DOI: 10.1002/ps.7524] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 04/25/2023] [Accepted: 05/03/2023] [Indexed: 05/04/2023]
Abstract
BACKGROUND The invasive fall armyworm (FAW) Spodoptera frugiperda (Lepidoptera: Noctuidae) has widely colonized the tropics and subtropics of Asia. However, the impact on the succession of the Asiatic corn borer (ACB) Ostrinia furnacalis (Lepidoptera: Pyralidae), a perennial dominant stemborer of maize in these areas, remains elusive. Here we analyzed the predation relationship, mimicked population competition, and surveyed the pest populations in the border area of Yunnan (southwestern China). RESULTS Laboratory assays revealed that the 2nd to 6th instar larvae of FAW preyed on ACB, and only the 4th and 5th instar larvae of ACB preyed on FAW (1st instar larvae only, 50% predation rate). The 6th instar FAW preyed on the 1st to 5th instar ACB with a theoretical maximum of 14.5-58.8 ACB individuals (per maize leaf) and 4.8-25.6 individuals (per tassel). When maize plants were infested with eggs of either FAW or ACB in field cage trials, maize damage was 77.6% and 50.6%, respectively, compared with 77.9% and 2.8% upon co-infestation. In field surveys conducted in 2019-2021, FAW density was significantly greater than that of ACB, which took a great impact on maize growth. CONCLUSION Our findings indicate that FAW can outcompete ACB at both the individual and population levels, which may result in FAW becoming the dominant pest. These results provide a scientific basis for further analysis of the mechanism by which FAW invades new agricultural areas and offers early-warning strategies for pest management. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Yifei Song
- Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xianming Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Hui Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Kongming Wu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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Tandy P, Lamour K, Placidi de Bortoli C, Nagoshi R, Emrich SJ, Jurat-Fuentes JL. Screening for resistance alleles to Cry1 proteins through targeted sequencing in the native and invasive range of Spodoptera frugiperda (Lepidoptera: Noctuidae). JOURNAL OF ECONOMIC ENTOMOLOGY 2023; 116:935-944. [PMID: 37311017 DOI: 10.1093/jee/toad061] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 03/02/2023] [Accepted: 03/30/2023] [Indexed: 06/15/2023]
Abstract
The fall armyworm, Spodoptera frugiperda (J. E. Smith), is a highly polyphagous pest native to the tropical Americas that has recently spread to become a global super-pest threatening food and fiber production. Transgenic crops producing insecticidal Cry and Vip3Aa proteins from Bacillus thuringiensis (Bt) are used for control of this pest in its native range. The evolution of practical resistance represents the greatest threat to sustainability of this technology and its potential efficacy in the S. frugiperda invasive range. Monitoring for resistance is vital to management approaches delaying S. frugiperda resistance to Bt crops. DNA-based resistance screening provides higher sensitivity and cost-effectiveness than currently used bioassay-based monitoring. So far, practical S. frugiperda resistance to Bt corn-producing Cry1F has been genetically linked to mutations in the SfABCC2 gene, providing a model to develop and test monitoring tools. In this study, we performed targeted SfABCC2 sequencing followed by Sanger sequencing to confirm the detection of known and candidate resistance alleles to Cry1F corn in field-collected S. frugiperda from continental USA, Puerto Rico, Africa (Ghana, Togo, and South Africa), and Southeast Asia (Myanmar). Results confirm that the distribution of a previously characterized resistance allele (SfABCC2mut) is limited to Puerto Rico and identify 2 new candidate SfABCC2 alleles for resistance to Cry1F, one of them potentially spreading along the S. frugiperda migratory route in North America. No candidate resistance alleles were found in samples from the invasive S. frugiperda range. These results provide support for the potential use of targeted sequencing in Bt resistance monitoring programs.
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Affiliation(s)
- Peter Tandy
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, TN 37996, USA
| | - Kurt Lamour
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, TN 37996, USA
| | | | - Rodney Nagoshi
- Center for Medical, Agricultural and Veterinary Entomology (CMAVE), United States Department of Agriculture-Agricultural Research Service, Gainesville, FL 32608, USA
| | - Scott J Emrich
- Department of Electrical Engineering and Computer Science, University of Tennessee, Knoxville, TN 37996, USA
| | - Juan Luis Jurat-Fuentes
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, TN 37996, USA
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Zhao S, Yang X, Liu D, Sun X, Li G, Wu K. Performance of the domestic Bt corn event expressing pyramided Cry1Ab and Vip3Aa19 against the invasive Spodoptera frugiperda (J. E. Smith) in China. PEST MANAGEMENT SCIENCE 2023; 79:1018-1029. [PMID: 36326028 DOI: 10.1002/ps.7273] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 10/24/2022] [Accepted: 11/03/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND The invasive fall armyworm, Spodoptera frugiperda (J.E. Smith), has caused serious corn yield losses and increased the frequency of insecticide spraying on corn in Africa and Asia. Drawing lessons from the use of Bt corn to manage fall armyworm in the Americas, China released a certificate for the genetically modified corn event DBN3601T pyramidally expressing Cry1Ab and Vip3Aa19 for industrialization in 2021. Performance of the DBN3601T event against invasive fall armyworm in China was evaluated by plant tissue-based bioassays and field trials during 2019-2021. RESULTS In the bioassays, tissues and organs of DBN3601T corn differed significantly in lethality to fall armyworm neonates in the order: leaf > husk > tassel and kernel > silk. In field trials, compared with non-Bt corn, DBN3601T corn greatly suppressed fall armyworm populations and damage; larval density, damage incidence, and leaf damage scores for DBN3601T corn were significantly lower than for non-Bt corn at different vegetative stages, and efficacy against larval populations during the 3 years ranged from 95.24% to 98.30%. CONCLUSION A laboratory bioassay and 3-year field trials confirmed that DBN3601T corn greatly suppressed fall armyworm populations and has high potential as a control of this invasive pest, making it a key tactic for integrated management of fall armyworm in China. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Shengyuan Zhao
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- Guangdong laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Xianming Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Dazhong Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiaoxu Sun
- Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou, China
| | - Guoping Li
- Key Laboratory of Integrated Pest Management on Crops in Southern Part of Northern China, Ministry of Agriculture and Rural Affairs, Institute of Plant Protection, Henan Academy of Agricultural Sciences, Zhengzhou, China
| | - Kongming Wu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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Kamweru I, Beyene Y, Bruce AY, Makumbi D, Adetimirin VO, Pérez-Rodríguez P, Toledo F, Crossa J, Prasanna BM, Gowda M. Genetic analyses of tropical maize lines under artificial infestation of fall armyworm and foliar diseases under optimum conditions. FRONTIERS IN PLANT SCIENCE 2023; 14:1086757. [PMID: 36743507 PMCID: PMC9896009 DOI: 10.3389/fpls.2023.1086757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 01/04/2023] [Indexed: 06/18/2023]
Abstract
Development and deployment of high-yielding maize varieties with native resistance to Fall armyworm (FAW), turcicum leaf blight (TLB), and gray leaf spot (GLS) infestation is critical for addressing the food insecurity in sub-Saharan Africa. The objectives of this study were to determine the inheritance of resistance for FAW, identity hybrids which in addition to FAW resistance, also show resistance to TLB and GLS, and investigate the usefulness of models based on general combining ability (GCA) and SNP markers in predicting the performance of new untested hybrids. Half-diallel mating scheme was used to generate 105 F1 hybrids from 15 parents and another 55 F1 hybrids from 11 parents. These were evaluated in two experiments, each with commercial checks in multiple locations under FAW artificial infestation and optimum management in Kenya. Under artificial FAW infestation, significant mean squares among hybrids and hybrids x environment were observed for most traits in both experiments, including at least one of the three assessments carried out for foliar damage caused by FAW. Interaction of GCA x environment and specific combining ability (SCA) x environment interactions were significant for all traits under FAW infestation and optimal conditions. Moderate to high heritability estimates were observed for GY under both management conditions. Correlation between GY and two of the three scorings (one and three weeks after infestation) for foliar damage caused by FAW were negative (-0.27 and -0.38) and significant. Positive and significant correlation (0.84) was observed between FAW-inflicted ear damage and the percentage of rotten ears. We identified many superior-performing hybrids compared to the best commercial checks for both GY and FAW resistance associated traits. Inbred lines CML312, CML567, CML488, DTPYC9-F46-1-2-1-2, CKDHL164288, CKDHL166062, and CLRCY039 had significant and positive GCA for GY (positive) and FAW resistance-associated traits (negative). CML567 was a parent in four of the top ten hybrids under optimum and FAW conditions. Both additive and non-additive gene action were important in the inheritance of FAW resistance. Both GCA and marker-based models showed high correlation with field performance, but marker-based models exhibited considerably higher correlation. The best performing hybrids identified in this study could be used as potential single cross testers in the development of three-way FAW resistance hybrids. Overall, our results provide insights that help breeders to design effective breeding strategies to develop FAW resistant hybrids that are high yielding under FAW and optimum conditions.
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Affiliation(s)
- Isaac Kamweru
- International Maize and Wheat Improvement Center (CIMMYT), Nairobi, Kenya
- Pan African University, Life and Earth Sciences Institute (Including Health and Agriculture), Ibadan, Nigeria
| | - Yoseph Beyene
- International Maize and Wheat Improvement Center (CIMMYT), Nairobi, Kenya
| | - Anani Y. Bruce
- International Maize and Wheat Improvement Center (CIMMYT), Nairobi, Kenya
| | - Dan Makumbi
- International Maize and Wheat Improvement Center (CIMMYT), Nairobi, Kenya
| | - Victor O. Adetimirin
- Department of Crop and Horticultural Sciences, University of Ibadan, Ibadan, Nigeria
| | - Paulino Pérez-Rodríguez
- Colegio de Postgraduados, Montecillo, Mexico
- Biometrics and Statistics Unit, International Maize and Wheat Improvement Center (CIMMYT), Texcoco, Mexico
| | - Fernando Toledo
- Biometrics and Statistics Unit, International Maize and Wheat Improvement Center (CIMMYT), Texcoco, Mexico
| | - Jose Crossa
- Biometrics and Statistics Unit, International Maize and Wheat Improvement Center (CIMMYT), Texcoco, Mexico
| | | | - Manje Gowda
- International Maize and Wheat Improvement Center (CIMMYT), Nairobi, Kenya
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11
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Rane R, Walsh TK, Lenancker P, Gock A, Dao TH, Nguyen VL, Khin TN, Amalin D, Chittarath K, Faheem M, Annamalai S, Thanarajoo SS, Trisyono YA, Khay S, Kim J, Kuniata L, Powell K, Kalyebi A, Otim MH, Nam K, d’Alençon E, Gordon KHJ, Tay WT. Complex multiple introductions drive fall armyworm invasions into Asia and Australia. Sci Rep 2023; 13:660. [PMID: 36635481 PMCID: PMC9837037 DOI: 10.1038/s41598-023-27501-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 01/03/2023] [Indexed: 01/14/2023] Open
Abstract
The fall armyworm (FAW) Spodoptera frugiperda is thought to have undergone a rapid 'west-to-east' spread since 2016 when it was first identified in western Africa. Between 2018 and 2020, it was recorded from South Asia (SA), Southeast Asia (SEA), East Asia (EA), and Pacific/Australia (PA). Population genomic analyses enabled the understanding of pathways, population sources, and gene flow in this notorious agricultural pest species. Using neutral single nucleotide polymorphic (SNP) DNA markers, we detected genome introgression that suggested most populations in this study were overwhelmingly C- and R-strain hybrids (n = 252/262). SNP and mitochondrial DNA markers identified multiple introductions that were most parsimoniously explained by anthropogenic-assisted spread, i.e., associated with international trade of live/fresh plants and plant products, and involved 'bridgehead populations' in countries to enable successful pest establishment in neighbouring countries. Distinct population genomic signatures between Myanmar and China do not support the 'African origin spread' nor the 'Myanmar source population to China' hypotheses. Significant genetic differentiation between populations from different Australian states supported multiple pathways involving distinct SEA populations. Our study identified Asia as a biosecurity hotspot and a FAW genetic melting pot, and demonstrated the use of genome analysis to disentangle preventable human-assisted pest introductions from unpreventable natural pest spread.
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Affiliation(s)
- Rahul Rane
- grid.1016.60000 0001 2173 2719CSIRO, 343 Royal Parade, Parkville, Melbourne, VIC 3052 Australia ,grid.1004.50000 0001 2158 5405Applied BioSciences, Macquarie University, Sydney, NSW Australia
| | - Thomas K. Walsh
- grid.1016.60000 0001 2173 2719CSIRO, Black Mountain Laboratories, Clunies Ross Street, Canberra, ACT 2601 Australia ,grid.1004.50000 0001 2158 5405Applied BioSciences, Macquarie University, Sydney, NSW Australia
| | - Pauline Lenancker
- grid.467576.1Sugar Research Australia, 71378 Bruce Highway, Gordonvale, QLD 4865 Australia
| | - Andrew Gock
- grid.1016.60000 0001 2173 2719CSIRO, Black Mountain Laboratories, Clunies Ross Street, Canberra, ACT 2601 Australia
| | - Thi Hang Dao
- Plant Protection Research Institute, Hanoi, Vietnam
| | | | | | - Divina Amalin
- grid.411987.20000 0001 2153 4317Department of Biology, De La Salle University, Manila, Philippines
| | | | - Muhammad Faheem
- CAB International Southeast Asia, Serdang, Kuala Lumpur, Malaysia
| | | | | | - Y. Andi Trisyono
- grid.8570.a0000 0001 2152 4506Department of Plant Protection, Faculty of Agriculture, Universitas Gadjah Mada, Depok, Indonesia
| | - Sathya Khay
- grid.473388.3Plant Protection Division of CARDI, Ministry of Agriculture, Forestry and Fisheries, Phnom Penh, Cambodia
| | - Juil Kim
- grid.412010.60000 0001 0707 9039College of Agriculture and Life Science, Kangwon National University, Chuncheon, Republic of Korea
| | - Lastus Kuniata
- grid.473451.0New Britain Palm Oil, Ramu Agri Industry Ltd., Lae, Papua New Guinea
| | - Kevin Powell
- grid.467576.1Sugar Research Australia, 71378 Bruce Highway, Gordonvale, QLD 4865 Australia
| | | | - Michael H. Otim
- grid.463519.c0000 0000 9021 5435National Crops Resources Research Institute, Namulonge, Kampala, Uganda
| | - Kiwoong Nam
- grid.503158.aDGIMI, Université Montpellier, INRAE, Montpellier, France
| | | | - Karl H. J. Gordon
- grid.1016.60000 0001 2173 2719CSIRO, Black Mountain Laboratories, Clunies Ross Street, Canberra, ACT 2601 Australia
| | - Wee Tek Tay
- CSIRO, Black Mountain Laboratories, Clunies Ross Street, Canberra, ACT, 2601, Australia. .,Applied BioSciences, Macquarie University, Sydney, NSW, Australia.
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12
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Wang Q, Yang D, Rui C, Zhou L, Li R, Wang L, Huang W, Ji X, Yang Q, Liang P, Yuan H, Cui L. Seed treatment with chlorantraniliprole and carbaryl mixture for managing fall armyworm on maize: systemic synergism, control efficiency and synergistic mechanism. PEST MANAGEMENT SCIENCE 2023; 79:464-473. [PMID: 36209490 DOI: 10.1002/ps.7215] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 07/28/2022] [Accepted: 09/26/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND Fall armyworm (Spodoptera frugiperda) is one of the major invasive pests in China, and has been widely controlled by labor-intensive foliar sprays of agrochemicals in maize (Zea mays L.). RESULTS Systemic bioassay showed that mixtures of chlorantraniliprole (Chlor) and carbaryl (Carb) had dramatically synergistic effect on toxicity to S. frugiperda. Particularly, a mixture of Chlor with Carb at a mass ratio of 2:1 (MCC) exhibited the highest toxicity to S. frugiperda. Therefore, seed treatment of Chlor mixed with Carb was studied as a simple, accurate, efficient and low-cost control technology. Our results showed that MCC treatment shortened the median lethal time and 90% lethal time to S. frugiperda compared to Chlor- and Carb-alone treatments. Meanwhile, smaller leaf consumption by S. frugiperda was recorded under MCC treatment compared to Chlor- and Carb-alone treatments. In field trial, maize-seed treatment with MCC showed efficacy up to 39 days post-emergence in preventing S. frugiperda foliar damage at a low infestation pressure. Moreover, chemical quantification by ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) showed that Chlor residues were more absorbed and concentrated in maize leaves of MCC treatment, compared to that of Chlor-alone treatment. CONCLUSION These results suggested that seed treatment with MCC can be applied to increase the control efficacy and reduce the cost of Chlor-alone treatment for controlling S. frugiperda. The present study provided evidence of an enhanced translocation and accumulation of Chlor residues in maize leaves under MCC treatment, which likely contributed to a synergistic effect against S. frugiperda. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Qinqin Wang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, China
- Department of Entomology, China Agricultural University, Beijing, China
| | - Daibin Yang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, China
| | - Changhui Rui
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, China
| | - Lin Zhou
- College of Plant Protection, Henan Agricultural University, Zhengzhou, China
| | - Runan Li
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, China
| | - Li Wang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, China
| | - Weiling Huang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, China
| | - Xuejiao Ji
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, China
| | - Qingjie Yang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, China
| | - Pei Liang
- Department of Entomology, China Agricultural University, Beijing, China
| | - Huizhu Yuan
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, China
| | - Li Cui
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, China
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Tay WT, Rane RV, James W, Gordon KHJ, Downes S, Kim J, Kuniata L, Walsh TK. Resistance Bioassays and Allele Characterization Inform Analysis of Spodoptera frugiperda (Lepidoptera: Noctuidae) Introduction Pathways in Asia and Australia. JOURNAL OF ECONOMIC ENTOMOLOGY 2022; 115:1790-1805. [PMID: 36515109 PMCID: PMC9748595 DOI: 10.1093/jee/toac151] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Indexed: 06/16/2023]
Abstract
The fall armyworm (FAW) Spodoptera frugiperda (Smith; Lepidoptera: Noctuidae) is present in over 70 countries in Africa, Asia, and Oceania. Its rapid dispersal since 2016 when it was first reported in western Africa, and associated devastation to agricultural productivity, highlight the challenges posed by this pest. Currently, its management largely relies on insecticide sprays and transgenic Bacillus thuringiensis toxins, therefore understanding their responses to these agents and characteristics of any resistance genes enables adaptive strategies. In Australia, S. frugiperda was reported at the end of January 2020 in northern Queensland and by March 2020, also in northern Western Australia. As an urgent first response we undertook bioassays on two Australian populations, one each from these initial points of establishment. To assist with preliminary sensitivity assessment, two endemic noctuid pest species, Helicoverpa armigera (Hübner; Lepidoptera, Noctuidae) and Spodoptera litura (Fabricius; Lepidoptera, Noctuidae), were concurrently screened to obtain larval LC50 estimates against various insecticides. We characterized known resistance alleles from the VGSC, ACE-1, RyR, and ABCC2 genes to compare with published allele frequencies and bioassay responses from native and invasive S. frugiperda populations. An approximately 10× LC50 difference for indoxacarb was detected between Australian populations, which was approximately 28× higher than that reported from an Indian population. Characterization of ACE-1 and VGSC alleles provided further evidence of multiple introductions in Asia, and multiple pathways involving genetically distinct individuals in Australia. The preliminary bioassay results and resistance allele patterns from invasive S. frugiperda populations suggest multiple introductions have contributed to the pest's spread and challenge the axiom of its rapid 'west-to-east' spread.
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Affiliation(s)
- W T Tay
- Corresponding author, e-mail:
| | - R V Rane
- Applied BioSciences, Macquarie University, Sydney, NSW 2100, Australia
- CSIRO, 343 Royal Parade, Parkville, VIC 3052, Australia
| | - W James
- CSIRO Black Mountain Laboratories, Clunies Ross Street, Acton, ACT 2601, Australia
| | - K H J Gordon
- CSIRO Black Mountain Laboratories, Clunies Ross Street, Acton, ACT 2601, Australia
| | - S Downes
- CSIRO McMaster Laboratories, New England Highway, Armidale, NSW 2350, Australia
| | - J Kim
- College of Agriculture and Life Science, Kangwon National University, Republic of Korea
| | | | - T K Walsh
- CSIRO Black Mountain Laboratories, Clunies Ross Street, Acton, ACT 2601, Australia
- Applied BioSciences, Macquarie University, Sydney, NSW 2100, Australia
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14
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Van den Berg J, Brewer MJ, Reisig DD. A Special Collection: Spodoptera frugiperda (Fall Armyworm): Ecology and Management of its World-Scale Invasion Outside of the Americas. JOURNAL OF ECONOMIC ENTOMOLOGY 2022; 115:1725-1728. [PMID: 36515103 DOI: 10.1093/jee/toac143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Indexed: 06/17/2023]
Abstract
The Special Collection 'Spodoptera frugiperda (fall armyworm): Ecology and Management of its World-scale Invasion Outside of the Americas' presents reviews and research that address topics of overarching interest and contributes to a better understanding of this pest and its management, now that it has spread outside the Americas. The collection is a combination of invited articles presenting new information published for the first time, invited review papers, and a selection of relevant high-quality articles previously published in Journal of Economic Entomology (JEE). Articles in the Collection, as well as selected citations of articles in other publications, reflect the increase in research on S. frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), which became the most important pest of maize in the world during recent years. This Special Collection addresses a wide range of topics, including pest behavior, host strains, insecticide and Bt protein resistance, biological control, host plant resistance, and yield loss estimates. Topics are presented in context of research primarily conducted in regions outside of the Americas where S. frugiperda has invaded and disrupted crop production to varying degrees. In recognition of further spread, the threat of a S. frugiperda invasion into Europe and potential management options are also presented.
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Affiliation(s)
- Johnnie Van den Berg
- IPM Program, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, 2520, South Africa
| | - Michael J Brewer
- Texas A&M AgriLife Research, Department of Entomology, Corpus Christi, TX 78406, USA
| | - Dominic D Reisig
- Department of Entomology, North Carolina State University, Vernon G. James Research and Extension Center, 207 Research Station Road, Plymouth, NC 27962, USA
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15
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Prasanna BM, Bruce A, Beyene Y, Makumbi D, Gowda M, Asim M, Martinelli S, Head GP, Parimi S. Host plant resistance for fall armyworm management in maize: relevance, status and prospects in Africa and Asia. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2022; 135:3897-3916. [PMID: 35320376 PMCID: PMC9729323 DOI: 10.1007/s00122-022-04073-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 03/01/2022] [Indexed: 05/16/2023]
Abstract
Sustainable control of fall armyworm (FAW) requires implementation of effective integrated pest management (IPM) strategies, with host plant resistance as a key component. Significant opportunities exist for developing and deploying elite maize cultivars with native genetic resistance and/or transgenic resistance for FAW control in both Africa and Asia. The fall armyworm [Spodoptera frugiperda (J.E. Smith); FAW] has emerged as a serious pest since 2016 in Africa, and since 2018 in Asia, affecting the food security and livelihoods of millions of smallholder farmers, especially those growing maize. Sustainable control of FAW requires implementation of integrated pest management strategies, in which host plant resistance is one of the key components. Significant strides have been made in breeding elite maize lines and hybrids with native genetic resistance to FAW in Africa, based on the strong foundation of insect-resistant tropical germplasm developed at the International Maize and Wheat Improvement Center, Mexico. These efforts are further intensified to develop and deploy elite maize cultivars with native FAW tolerance/resistance and farmer-preferred traits suitable for diverse agro-ecologies in Africa and Asia. Independently, genetically modified Bt maize with resistance to FAW is already commercialized in South Africa, and in a few countries in Asia (Philippines and Vietnam), while efforts are being made to commercialize Bt maize events in additional countries in both Africa and Asia. In countries where Bt maize is commercialized, it is important to implement a robust insect resistance management strategy. Combinations of native genetic resistance and Bt maize also need to be explored as a path to more effective and sustainable host plant resistance options. We also highlight the critical gaps and priorities for host plant resistance research and development in maize, particularly in the context of sustainable FAW management in Africa and Asia.
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Affiliation(s)
- Boddupalli M Prasanna
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, P.O. Box 1041, GigiriNairobi, 00621, Kenya.
| | - Anani Bruce
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, P.O. Box 1041, GigiriNairobi, 00621, Kenya
| | - Yoseph Beyene
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, P.O. Box 1041, GigiriNairobi, 00621, Kenya
| | - Dan Makumbi
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, P.O. Box 1041, GigiriNairobi, 00621, Kenya
| | - Manje Gowda
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, P.O. Box 1041, GigiriNairobi, 00621, Kenya
| | | | | | - Graham P Head
- Regulatory Science, Bayer Crop Science US, Chesterfield, MO, USA
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16
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Van den Berg J, Greyvenstein B, du Plessis H. Insect resistance management facing African smallholder farmers under climate change. CURRENT OPINION IN INSECT SCIENCE 2022; 50:100894. [PMID: 35247642 DOI: 10.1016/j.cois.2022.100894] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 02/18/2022] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
Changes in climatic conditions affect pest populations and ultimately result in increased pest status and yield losses. While pesticide application is usually the first defensive tool used to control pest species that threaten crop production, genetically modified (GM) crops with insecticidal traits (Bt crops) are becoming more common. The indiscriminate and over use of insecticides, and absence of insect resistance management (IRM) strategies ultimately lead to evolution of resistance against these technologies. IRM faces significant challenges in the African context. In this paper we use examples of cotton, maize, cowpea and tomato pests to illustrate their potential to evolve resistance to insecticides and also highlight the importance of IRM strategies, both with regard to the use of pesticides and the cultivation of Bt cotton, Bt maize and Bt cowpea.
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Affiliation(s)
- Johnnie Van den Berg
- IPM Program, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, 2520, South Africa.
| | - Bianca Greyvenstein
- IPM Program, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, 2520, South Africa
| | - Hannalene du Plessis
- IPM Program, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, 2520, South Africa
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17
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Reavey CE, Walker AS, Joyce SP, Broom L, Willse A, Ercit K, Poletto M, Barnes ZH, Marubbi T, Troczka BJ, Treanor D, Beadle K, Granville B, de Mello V, Teal J, Sulston E, Ashton A, Akilan L, Naish N, Stevens O, Humphreys-Jones N, Warner SAJ, Spinner SAM, Rose NR, Head G, Morrison NI, Matzen KJ. Self-limiting fall armyworm: a new approach in development for sustainable crop protection and resistance management. BMC Biotechnol 2022; 22:5. [PMID: 35086540 PMCID: PMC8793274 DOI: 10.1186/s12896-022-00735-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 01/11/2022] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The fall armyworm, Spodoptera frugiperda, is a significant and widespread pest of maize, sorghum, rice, and other economically important crops. Successful management of this caterpillar pest has historically relied upon application of synthetic insecticides and through cultivation of genetically engineered crops expressing insecticidal proteins (Bt crops). Fall armyworm has, however, developed resistance to both synthetic insecticides and Bt crops, which risks undermining the benefits delivered by these important crop protection tools. Previous modelling and empirical studies have demonstrated that releases of insecticide- or Bt-susceptible insects genetically modified to express conditional female mortality can both dilute insecticide resistance and suppress pest populations. RESULTS Here, we describe the first germline transformation of the fall armyworm and the development of a genetically engineered male-selecting self-limiting strain, OX5382G, which exhibits complete female mortality in the absence of an additive in the larval diet. Laboratory experiments showed that males of this strain are competitive against wild-type males for copulations with wild-type females, and that the OX5382G self-limiting transgene declines rapidly to extinction in closed populations following the cessation of OX5382G male releases. Population models simulating the release of OX5382G males in tandem with Bt crops and non-Bt 'refuge' crops show that OX5382G releases can suppress fall armyworm populations and delay the spread of resistance to insecticidal proteins. CONCLUSIONS This article describes the development of self-limiting fall armyworm designed to control this pest by suppressing pest populations, and population models that demonstrate its potential as a highly effective method of managing resistance to Bt crops in pest fall armyworm populations. Our results provide early promise for a potentially valuable future addition to integrated pest management strategies for fall armyworm and other pests for which resistance to existing crop protection measures results in damage to crops and impedes sustainable agriculture.
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Affiliation(s)
| | - Adam S Walker
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Stephen P Joyce
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Lucy Broom
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
- Centre for Medicines Discovery, University of Oxford, Old Road Campus Research Build, Roosevelt Dr, Headington, Oxford, OX3 7DQ, UK
| | - Alan Willse
- Bayer Crop Science, Chesterfield, MO, 63017, USA
| | - Kyla Ercit
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Mattia Poletto
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Zoe H Barnes
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Thea Marubbi
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | | | - David Treanor
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Katherine Beadle
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Ben Granville
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Vanessa de Mello
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Joss Teal
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Edward Sulston
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Anna Ashton
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Luxziyah Akilan
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Neil Naish
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Oliver Stevens
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | | | - Simon A J Warner
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
- Oxford University Innovation, Buxton Court, 3 West Way, Oxford, OX2 0JB, UK
| | - Sian A M Spinner
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Nathan R Rose
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK.
| | - Graham Head
- Bayer Crop Science, Chesterfield, MO, 63017, USA
| | - Neil I Morrison
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK
| | - Kelly J Matzen
- Oxitec Ltd, 71 Innovation Drive, Milton Park, Abingdon, OX14 4RQ, UK.
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18
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Van den Berg J, Prasanna BM, Midega CAO, Ronald PC, Carrière Y, Tabashnik BE. Managing Fall Armyworm in Africa: Can Bt Maize Sustainably Improve Control? JOURNAL OF ECONOMIC ENTOMOLOGY 2021; 114:1934-1949. [PMID: 34505143 DOI: 10.1093/jee/toab161] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Indexed: 05/28/2023]
Abstract
The recent invasion of Africa by fall armyworm, Spodoptera frugiperda, a lepidopteran pest of maize and other crops, has heightened concerns about food security for millions of smallholder farmers. Maize genetically engineered to produce insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) is a potentially useful tool for controlling fall armyworm and other lepidopteran pests of maize in Africa. In the Americas, however, fall armyworm rapidly evolved practical resistance to maize producing one Bt toxin (Cry1Ab or Cry1Fa). Also, aside from South Africa, Bt maize has not been approved for cultivation in Africa, where stakeholders in each nation will make decisions about its deployment. In the context of Africa, we address maize production and use; fall armyworm distribution, host range, and impact; fall armyworm control tactics other than Bt maize; and strategies to make Bt maize more sustainable and accessible to smallholders. We recommend mandated refuges of non-Bt maize or other non-Bt host plants of at least 50% of total maize hectares for single-toxin Bt maize and 20% for Bt maize producing two or more distinct toxins that are each highly effective against fall armyworm. The smallholder practices of planting more than one maize cultivar and intercropping maize with other fall armyworm host plants could facilitate compliance. We also propose creating and providing smallholder farmers access to Bt maize that produces four distinct Bt toxins encoded by linked genes in a single transgene cassette. Using this novel Bt maize as one component of integrated pest management could sustainably improve control of lepidopteran pests including fall armyworm.
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Affiliation(s)
- Johnnie Van den Berg
- Unit for Environmental Sciences and Management, IPM Program, North-West University, Potchefstroom, 2520, South Africa
| | - Boddupalli M Prasanna
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, Nairobi, 00601, Kenya
| | - Charles A O Midega
- Unit for Environmental Sciences and Management, IPM Program, North-West University, Potchefstroom, 2520, South Africa
- Poverty and Health Integrated Solutions, Kisumu, 40141, Kenya
| | - Pamela C Ronald
- Department of Plant Pathology and the Genome Center, University of California, Davis, CA 95616, USA
| | - Yves Carrière
- Department of Entomology, University of Arizona, Tucson, AZ 85721, USA
| | - Bruce E Tabashnik
- Department of Entomology, University of Arizona, Tucson, AZ 85721, USA
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Wengrat APGS, Coelho Junior A, Parra JRP, Takahashi TA, Foerster LA, Corrêa AS, Polaszek A, Johnson NF, Costa VA, Zucchi RA. Integrative taxonomy and phylogeography of Telenomus remus (Scelionidae), with the first record of natural parasitism of Spodoptera spp. in Brazil. Sci Rep 2021; 11:14110. [PMID: 34238969 PMCID: PMC8266905 DOI: 10.1038/s41598-021-93510-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/24/2021] [Indexed: 02/06/2023] Open
Abstract
The egg parasitoid Telenomus remus (Hymenoptera: Scelionidae) has been investigated for classical and applied biological control of noctuid pests, especially Spodoptera (Lepidoptera: Noctuidae) species. Although T. remus was introduced into Brazil over three decades ago for classical biological control of S. frugiperda, this wasp has not been recorded as established in corn or soybean crops. We used an integrative approach to identify T. remus, combining a taxonomic key based on the male genitalia with DNA barcoding, using a cytochrome c oxidase subunit I mitochondrial gene fragment. This is the first report of natural parasitism of T. remus on S. frugiperda and S. cosmioides eggs at two locations in Brazil. We also confirmed that the T. remus lineage in Brazil derives from a strain in Venezuela (originally from Papua New Guinea and introduced into the Americas, Africa, and Asia). The occurrence of T. remus parasitizing S. frugiperda and S. cosmioides eggs in field conditions, not associated with inundative releases, suggests that the species has managed to establish itself in the field in Brazil. This opens possibilities for future biological control programs, since T. remus shows good potential for mass rearing and egg parasitism of important agricultural pests such as Spodoptera species.
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Affiliation(s)
- Ana P. G. S. Wengrat
- grid.11899.380000 0004 1937 0722Department of Entomology and Acarology, University of São Paulo (USP)/Luiz de Queiroz College of Agriculture (ESALQ), Piracicaba, São Paulo Brazil
| | - Aloisio Coelho Junior
- grid.11899.380000 0004 1937 0722Department of Entomology and Acarology, University of São Paulo (USP)/Luiz de Queiroz College of Agriculture (ESALQ), Piracicaba, São Paulo Brazil
| | - Jose R. P. Parra
- grid.11899.380000 0004 1937 0722Department of Entomology and Acarology, University of São Paulo (USP)/Luiz de Queiroz College of Agriculture (ESALQ), Piracicaba, São Paulo Brazil
| | - Tamara A. Takahashi
- grid.20736.300000 0001 1941 472XDepartment of Phytotechnics and Plant Health, Federal University of Paraná, Curitiba, Paraná Brazil
| | - Luis A. Foerster
- grid.20736.300000 0001 1941 472XDepartament of Zoology, Federal University of Paraná, Curitiba, Paraná Brazil
| | - Alberto S. Corrêa
- grid.11899.380000 0004 1937 0722Department of Entomology and Acarology, University of São Paulo (USP)/Luiz de Queiroz College of Agriculture (ESALQ), Piracicaba, São Paulo Brazil
| | - Andrew Polaszek
- grid.35937.3b0000 0001 2270 9879Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD UK
| | - Norman F. Johnson
- grid.261331.40000 0001 2285 7943Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, 1315 Kinnear Road, Columbus, OH 43212 USA
| | - Valmir A. Costa
- grid.419041.90000 0001 1547 1081Instituto Biológico, Unidade Laboratorial de Referência em Controle Biológico, Campinas, São Paulo Brazil
| | - Roberto A. Zucchi
- grid.11899.380000 0004 1937 0722Department of Entomology and Acarology, University of São Paulo (USP)/Luiz de Queiroz College of Agriculture (ESALQ), Piracicaba, São Paulo Brazil
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Matova PM, Kamutando CN, Magorokosho C, Kutywayo D, Gutsa F, Labuschagne M. Fall-armyworm invasion, control practices and resistance breeding in Sub-Saharan Africa. CROP SCIENCE 2020; 60:2951-2970. [PMID: 33328691 PMCID: PMC7702106 DOI: 10.1002/csc2.20317] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 08/25/2020] [Accepted: 08/25/2020] [Indexed: 05/02/2023]
Abstract
Fall armyworm [Spodoptera frugiperda (J.E. Smith); FAW] invasion has exacerbated maize (Zea mays L.) crop yield losses in sub-Saharan Africa (SSA), already threatened by other stresses, especially those that are climate-change induced. The FAW is difficult to control, manage, or eradicate, because it is polyphagous and trans-boundary, multiplies fast, has a short life cycle and migrates easily, and lacks the diapause growth phase. In this study, FAW and its impact in Africa was reviewed, as well as past and present control strategies for this pest. Pesticides, cultural practices, natural enemies, host-plant resistance, integrated pest management (IPM), and plant breeding approaches were examined as possible control strategies. It was concluded that an IPM control strategy, guided by cultural approaches already being used by farmers, and what can be adopted from the Americas, coupled with an insect-resistance management strategy, is the best option to manage this pest in Africa. These strategies will be strengthened by breeding for multi-trait host-plant resistance through stacking of genes for different modes of control of the pest.
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Affiliation(s)
- Prince M. Matova
- Department of Research and Specialist ServicesCrop Breeding Institute5th Street ExtensionHarareZimbabwe
- International Maize and Wheat Improvement CentreHarareZimbabwe
- Department of Plant SciencesUniversity of the Free StateBloemfonteinSouth Africa
| | | | | | - Dumisani Kutywayo
- Department of Research and Specialist ServicesCrop Breeding Institute5th Street ExtensionHarareZimbabwe
| | - Freeman Gutsa
- Department of Research and Specialist ServicesCrop Breeding Institute5th Street ExtensionHarareZimbabwe
| | - Maryke Labuschagne
- Department of Plant SciencesUniversity of the Free StateBloemfonteinSouth Africa
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Jing D, Guo J, Jiang Y, Zhao J, Sethi A, He K, Wang Z. Initial detections and spread of invasive Spodoptera frugiperda in China and comparisons with other noctuid larvae in cornfields using molecular techniques. INSECT SCIENCE 2020; 27:780-790. [PMID: 31209955 PMCID: PMC7317731 DOI: 10.1111/1744-7917.12700] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 06/15/2019] [Accepted: 06/16/2019] [Indexed: 05/06/2023]
Abstract
The fall armyworm, Spodoptera frugiperda, is a species native to the Americas and has spread to many countries in Africa and Asia in recent years. Proactive actions for potential invasion of S. frugiperda to China coordinated by government agencies and agricultural extension systems resulted in timely detection in January 2019 in Yunnan province neighboring onto Myanmar. The extensive monitoring in southern provinces of China since February 2019 resulted in dynamic tracking of S. frugiperda spreading to 13 provincial regions in China within 4 months by May 10, 2019, which is crucial for timely management actions in the fields. The first detections of S. frugiperda (corn strain) in China were confirmed using cytochrome oxidase subunit 1 (CO1) and triosephosphate isomerase (Tpi) genes molecular marker method. In addition to S. frugiperda, larvae of three other noctuid species with similar morphological appearance (S. litura, S. exigua and Mythimna separata) can occur simultaneously and cause similar damage in cornfields in southern China. Thus, we can use both morphological and molecular marker methods to compare larval stages of four noctuid species. Further, we discuss the risk of potential spread of invasive S. frugiperda to other regions and impact on corn production in China.
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Affiliation(s)
- Da‐Peng Jing
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant Protection, Chinese Academy of Agricultural SciencesBeijingChina
| | - Jing‐Fei Guo
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant Protection, Chinese Academy of Agricultural SciencesBeijingChina
| | - Yu‐Ying Jiang
- China National AgroTech Extension and Service CenterBeijingChina
| | | | | | - Kang‐Lai He
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant Protection, Chinese Academy of Agricultural SciencesBeijingChina
| | - Zhen‐Ying Wang
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant Protection, Chinese Academy of Agricultural SciencesBeijingChina
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Gichuhi J, Sevgan S, Khamis F, Van den Berg J, du Plessis H, Ekesi S, Herren JK. Diversity of fall armyworm, Spodoptera frugiperda and their gut bacterial community in Kenya. PeerJ 2020; 8:e8701. [PMID: 32185109 PMCID: PMC7060952 DOI: 10.7717/peerj.8701] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 02/06/2020] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND The invasive fall armyworm, Spodoptera frugiperda (J.E. Smith) is a polyphagous pest that causes widespread damage particularly to maize and sorghum in Africa. The microbiome associated with S. frugiperda could play a role in the insects' success and adaptability. However, bacterial communities in S. frugiperda remain poorly studied. METHODS We investigated the composition, abundance and diversity of microbiomes associated with larval and adult specimens of S. frugiperda collected from four maize growing regions in Kenya through high throughput sequencing of the bacterial 16S rRNA gene. The population structure of S. frugiperda in Kenya was assessed through amplification of the mitochondrial cytochrome oxidase subunit I gene. RESULTS We identified Proteobacteria and Firmicutes as the most dominant bacterial phyla and lesser proportions of Bacteroidetes and Actinobacteria. We also observed differences in bacterial microbiome diversity between larvae and adults that are a likely indication that some prominent larval bacterial groups are lost during metamorphosis. However, several bacterial groups were found in both adults and larvae suggesting that they are transmitted across developmental stages. Reads corresponding to several known entomopathogenic bacterial clades as well as the fungal entomopathogen, Metarhizium rileyi, were observed. Mitochondrial DNA haplotyping of the S. frugiperda population in Kenya indicated the presence of both "Rice" and "Corn" strains, with a higher prevalence of the "Rice" strain.
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Affiliation(s)
- Joseph Gichuhi
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya
| | - Subramanian Sevgan
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya
| | - Fathiya Khamis
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya
| | - Johnnie Van den Berg
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Hannalene du Plessis
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Sunday Ekesi
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya
| | - Jeremy K. Herren
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya
- MRC-University of Glasgow Centre for Virus Research, Henry Wellcome Building, Glasgow, UK
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