Management Of Armyworm Research Articles

Genome-wide identification of Cytochrome P450 gene in Fall Armyworm (Spodoptera frugiperda) in response to insecticide resistance

The fall armyworm (FAW), Spodoptera frugiperda, poses a significant threat to maize, sorghum, and cotton crops, leading to substantial economic losses of up to 80 % in severe infestations. Despite its economic impact, the characterization of Cytochrome P450 (Cyp) genes, pivotal in regulatory metabolic processes, remains unexplored. This study identifies and investigates 33 Cyp-genes involved in critical metabolic pathways. These include fatty acid metabolism, resistance mechanisms, hormone regulation affecting moulting and developmental stages, response to phytotoxins, and detoxification of insecticides.Utilizing in-silico gene expression profiling, we pinpoint key Cyp-genes—Cyp306a1-like, Cyp9e2-like, Cyp6l1-like, Cyp12b1, and Cyp6B2-like—playing critical roles in conferring resistance against four commonly used insecticides: emamectin benzoate, tetrazolium, cyantraniliprole, and spinetoram. Our findings reveal that these identified genes are essential in detoxifying chemical treatments, thus contributing to the development of resistance in fall armyworm populations. In this investigation, key genes such as Cyp306a1-like, Cyp9e2-like, and Cyp6l1-like emerge as important regulatory genes. These genes play a role in resistance and detoxification when exposed to chemical stress. This in-silico study provides insights into the genetic mechanisms underlying resistance and regulatory genes in the fall armyworm, shedding light on potential targets for controlling the notorious agricultural pest. However, further comprehensive investigations are needed to elucidate the intricate resistance mechanisms governed by these key genes, paving the way for developing novel and effective strategies for fall armyworm management in agricultural ecosystems.

Assessing homogeneous and heterogeneous economic impacts of fall armyworm management practices on farm performance in Ghana

One of the emerging challenges impinging on sustainable food production in sub-Saharan Africa is the invasion of the fall armyworm (FAW) pest. Data collected from farm households in different agro-ecological zones in Ghana and a Multivalued Treatment Effect (MVTE) model were used to argue that FAW management practices are key to stemming the debilitating effects of FAW infestations on farm performance. Previous studies have analysed homogeneous treatment effects to explain FAW management practices. The present study employs heterogeneous treatment effects to account for the differential effects of FAW management practices such as early planting, application of prescribed pesticides, and a combination of both practices while accounting for socioeconomic characteristics. Findings from the study reveal that distance to extension services exerts negative effects on adoption of early planting only, and adoption of both FAW management practices. Moreover, past FAW infestations tend to exert a positive effect on adoption of pesticide application only and adoption of a combination of the FAW management practices. Adopting the FAW management practices examined in this study assisted the maize producers in raising their farm performance. Socioeconomic characteristics also tend to influence the homogeneous treatment effects of adoption of the FAW management practices on farm performance. This finding indicates that heterogeneity within farm households is crucial for policy regarding adoption of FAW management practices.

Evaluating local plant species for effective fall armyworm management strategies in Taiwan

BackgroundThe emergence of Spodoptera frugiperda (fall armyworm; FAW) in the world has raised concerns regarding its impact on crop production, particularly on corn and sorghum. While chemical control and Bt crops have been effective in managing FAW damage, the development of pesticide-resistant and Bt-resistant strains necessitates alternative control methods. The push-pull farming system has gained attention, but direct utilization of African plant species in Taiwan faces challenges due to invasive potential and climatic disparities. Therefore, identifying and evaluating suitable local plant species, such as Napier grass (Pennisetum purpureum), Desmodium species, and signal grass (Brachiaria brizantha), is crucial for implementing effective FAW management strategies in Taiwan.ResultsIn screening fifty Napier grass germplasms, all demonstrated an antibiotic effect, reducing leaf consumption compared to corn. Notably, thirty-five germplasms exhibited robust antibiotic traits, decreasing FAW consumption and increasing mortality rates. Three Napier grass germplasms also attracted more female moths for oviposition. Further evaluation of selected Napier grass germplasms and signal grass demonstrated efficacy in reducing FAW larval weight and survival duration. Additionally, Desmodium species, particularly D. uncinatum, showed promising toxicity against FAW larvae.ConclusionOur findings support the effectiveness of selected Napier grass germplasms and signal grass as pull plants, and highlight the potential of D. uncinatum as a push plant in FAW management strategies in Taiwan.

The nexus between information sources, gender and adoption of fall armyworm management practices in Southern Ghana

The impact of Fall Army Worm (FAW) infestation on the livelihood outcomes of farmers in Africa is an issue of critical concern. Specificities of information sources and their efficacy in the management of Fall Armyworm remain crucial. Yet still, the nexus between farmers’ information sources and the management of Fall Armyworm appears scarce in the related literature pertaining to the global south. This article answers the research question: What is the relationship between specific information sources and the management practices of Fall Army Worm in Ghana? Using cross-sectional data on 340 smallholder farmers, the findings showed that information derived from peer farmers, Agricultural extension officers, and the media related to the adoption of fall armyworm management practices. Additionally, information from agricultural extension agents has a significant relationship with the use of pesticides, handpicking, and frequent weeding. Generally, the majority (97%) of smallholder farmers remained aware of the presence of FAW and had been negatively affected. We recommend that peer-to-peer extension be harnessed and scaled up in the dissemination of useful agricultural information given the shortfall in adequate agricultural extension officers in Ghana and most countries in Sub-Saharan Africa.

Potential Environmental Risks During Fall Armyworm Management Strategies by Gender in Bomet County, Kenya

Potential Environmental Risks During Fall Armyworm Management Strategies by Gender in Bomet County, Kenya

Management of Fall Armyworm (Spodoptera frugiperda) in Maize with Oil Based Formulations of Metarhizium rileyi

Maize, a vital cereal crop globally and in India, faces productivity challenges exacerbated by invasive pests like the fall armyworm. In response, eco-friendly strategies like microbial-based pesticides, including Metarhizium rileyi, is emerging as promising solution. This study addresses the challenge for effective fall armyworm management by utilizing M. rileyi oil based formulations. Results demonstrate significant larval reduction, with sunflower oil-based formulations achieving the highest reduction of 49.12% compared to control. These findings underscore the potential of M. rileyi formulations, particularly in sunflower oil, as valuable tools in integrated pest management strategies for maize crops.

Impact of Spodoptera frugiperda (Lepidoptera: Noctuidae), on maize yield in humid tropical zones of Central Africa.

Fall armyworm, Spodoptera frugiperda Smith, became the most important maize pest in Africa in 2016, with management based on chemical pesticides. High yield losses across the continent were predicted based on farmers' perceptions, but existing agroecological differences were not considered. In the Democratic Republic of Congo, experiments were conducted to assess fall armyworm damage and yield losses in maize farms with and without treatment. The study included 2 seasons in the Kipopo wetland in 2020 and 2021, one rainy season in Kanyameshi in 2021, 2 rainy seasons in Mulungu in 2020 and 2021, and one season in a wetland on the Bishibiru site in 2020. In addition, the research was also conducted at 4 sites in Cameroon from September to December 2020 and from March to July 2021. High levels of damage incidences were recorded, but the density of larvae per plant was low, with low to moderate levels of damage severities in different seasons and sites. Treatment significantly reduced the number of fall armyworm larvae and their damage severity. However, the high infestation levels did not significantly reduce yield. Cost-benefit ratios were either negative or, in most cases, less than 1. In the best case, the use of pesticides only allowed the recovery of the amount used for the intervention. We discussed the implications of these findings for fall armyworm management in humid tropical agroecology.

Effects of Biorational Approaches and Synthetic Pesticides on Fall Armyworm Management and Arthropod Diversity in Maize

Effects of Biorational Approaches and Synthetic Pesticides on Fall Armyworm Management and Arthropod Diversity in Maize

Evaluating the knowledge and perceptions of local farmers in Tanam Village, Morobe Province regarding Fall Armyworm infestation

This research presents farmers’ knowledge, attitudes, and management strategies for the autumn armyworm (Spodoptera frugiperda) in the Huon Gulf District and Tanam Village Market in Morobe Province, Papua New Guinea. This is the first study that focuses on the opinions and expertise of local farmers in the region, identifying crop-related issues and learning about their management techniques. The survey sites chosen were the Huon Gulf District and Tanam Village Market in Morobe Province, Papua New Guinea. Various farmers who grew different crops, such as sweet potatoes, bananas, taro, greens, maize, peanuts, fruits, and more, were interviewed during the research. Findings reveal that around 20 farmers participated in this random survey, with 55% falling between the ages of 25 and 35. However, there was a significant variation in age distribution, with 15% being quite old (51–70 years old) and 30% in the medium age range (36–50 years old). In conclusion, it is crucial to understand the perspectives and knowledge held by the local farmers in Papua New Guinea regarding fall armyworms. This will help develop innovative solutions to mitigate the consequences of this pest before they worsen and spread to other nations. This report emphasizes the importance of creating autumn armyworm management plans that consider farmers’ needs and goals.

Integrating Entomopathogenic Fungi into Different Crop Management Practices for Fall Armyworm Management

The study was carried out to identify crop management practices favouring entomopathogenic fungi of fall armyworm (Spodoptera frugiperda J. E. Smith). An experiment was set up with 24 maize plots measuring 6 m x 5 m in Siaya, JOOUST Campus field during the September to December 2021 short rain season for identification of crop management practices favouring entomopathogenic fungi of fall armyworm. Morphological and Molecular characterization was done to estimate the diversity of entomopathogenic fungi offal armyworm larvae specimens from the treatment plots. Each plot was separated by 2 m occupied with Brachiaria CV Mulato to counter the possibility of fall armyworm migration from one treatment plot to another as recommended by the ICIPE’s fall armyworm push-pull technology. The results showed that weeding was statistically significant (0.044) on fall armyworm larvae collected while only 2 species of entomopathogenic fungi were isolated for this crop management practice. The case was different with intercropping, though not statistically significant, over 50% of the isolated species were from this management practice. This could mean that intercropping is likely to reduce FAW larvae infestation whilst increasing fungal activity. This study therefore concludes that the threat that S. frugiperda poses also calls for the need for the development and adoption of good crop management practices such as intercropping, adequate fertilization, and weeding

Implementation of Fall Armyworm Management Plan in Ghana

Abstract Fall armyworm (FAW), an invasive pest, was confirmed in Ghana in 2016. As a result, a group of stakeholders developed a national FAW management plan. This case considers a review of the management plan conducted through outcome harvesting, a Sprockler (story-based) inquiry, and interviews with key informants. The review found evidence of stakeholder collaboration, increased public awareness of FAW and management practices, and more coordinated research into low-risk management options. It also found that the formal taskforce structure, common goals and ownership, effective collaboration and communication, and a commitment to implementing the action plan by all actors were the key factors in the FAW response. Challenges included a slow initial response, inadequate funds, and limitations in the agricultural extension system. Key steps to ensure future preparedness include implementation of the National Invasive Species Strategy and Action Plan (NISSAP), establishment of a standing taskforce and emergency fund to address new pest outbreaks, improved monitoring and surveillance especially at borders and ports of entry, strengthened research capacity, especially in pest risk analyses, involvement of all stakeholders at central and local levels, and development of generic and specific emergency response guidelines for future outbreaks. Information © CAB International 2023

Evaluation on the Efficacy of Synthetic insecticides for the Management of Fall Armyworm, Spodoptera frugiperda (J.E. Smith (Lepidoptera: Noctuidae) in Maize

Fall armyworm, Spodoptera frugiperda is an invasive and notorious pest of maize in many countries including Nepal. Several approaches of integrated management have been adopted for its control, chemical being the most popular choice in the farmers’ fields. Efficacy of such chemical pesticides for fall armyworm is interpreted as per the location, season, time and crops. In some cases, insect pests are always increasing the pesticide resistance. Hence to minimize the confusion of insecticide efficiency in various levels of understanding in the farmers’ level, field research was conducted in October 2021 to April, 2022. Seven different treatments (azadirachtin, chlorantraniliprole, emamectin benzoate, spinosad, spinetoram, imidacloprid and control) were tested in a four replicated RCBD design. Two sprays were made in twenty-days after seeding and fifteen-days after first spray in openfield condition. Minimum damage across various stages of maize plant was recorded inspinosad sprayed plots followed by spinetoram, chlorantraniliprole and emamectin benzoate, respectively. Maize yield was also recorded highest in spinosad and spinetoram sprayed plots. Highest score of damage was recorded in imidacloprid treated plots. This study further proved spinosad and spinetoram are the most popularly applied insecticides for the fall armyworm management.

Gender Roles Influencing Fall Armyworm Management Towards Environmental and Food Production Resilience in Bomet County, Kenya

Gender Roles Influencing Fall Armyworm Management Towards Environmental and Food Production Resilience in Bomet County, Kenya

Comparative effects of biopesticides on fall armyworm management and larval parasitism rates in northern Ghana

The outbreak of the fall armyworm, Spodoptera frugiperda, in Africa has led to several recommendations of insecticides, including biopesticides. However, the effects of these products on the environment, especially on parasitoids have not been assessed under field conditions. Here, we investigated the effect of commonly used biopesticides on S. frugiperda management and larval parasitoids of S. frugiperda in northern Ghana. The experiments were conducted both on-station in Wa and Nyankpala and on-farm in Wa during the 2020 rainy season. Active ingredients tested included neem oil (3% Azadirachtin), maltodextrin (282 g/l), 55% Bacillus thuringiensis (Bt) combined with 45% Monosultap, and a Pieris rapae granulosis virus combined with 5% Bt. A chemical insecticide based on emamectin benzoate and acetamiprid was used as positive control while non-treated maize plots were considered as untreated control. The two most abundant parasitoids in Wa were Coccygidium luteum and Chelonus bifoveolatus, while in Nyankpala they were C. luteum and Meteorus sp. Total larval parasitism rates on-station were 18.7% and 17.6% in Wa and Nyankpala, respectively, and 8.8% in Wa on-farm. Parasitoid species diversity and evenness indexes did not vary among treatments, but parasitism rates were significantly lower with the chemical on-station in Wa and with the virus and Bt product in Nyankpala. Untreated maize plots showed the highest larval density and plant damage, the highest cob damage, and generated the lowest yields. The other treatments showed hardly any difference in cob damage and yields, suggesting that biopesticides should be preferred over chemical pesticides for S. frugiperda control.

Fall Armyworm: Current Status in Nepal, its Management and Way Forward

Fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is an economically important invasive pest species primarily infesting maize. It is highly polyphagous and migratory in nature, posing a threat to several economically important crops. This pest has traveled a long journey from the American continent to Asia via Africa. This insect has inflicted substantial damage to Maize’s crop productivity of Maize in Nepal, since its introduction in May 2019 and has now become widespread from plain regions to hilly regions of the country. Therefore, this pest problem is considered a major issue for research and development in the country. The lessons from world research and development in the fall armyworm management could be adapted and used in Nepal after its proper validation. In order to identify the current status of fall armyworm in Nepal and the management of the insect species, we have discussed overviews on biology, ecology, origin and distribution pathway, management, and way forward, focusing on sustainable measures which could be useful for designing integrated pest management of fall armyworm in Nepal since knowledge gap is large.

Host plant preference by the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Noctuidae: Lepidoptera) on the range of potential host plant species

Maize is the most important cereal crop after rice and wheat in Asia. Nowadays, maize production is threatened by one invasive pest, the fall armyworm (Spodoptera frugiperda) particularly in Africa and Asia, and threatens millions of poor people. Fall armyworm feeds a wide range of crops and non-crops including weeds, with over 353 plant species. But most frequently consumed crops are field corn, sweet corn, wheat, sorghum, sugarcane, Bermuda grass etc. Fall armyworm has six larval stages, the first three stages are less voracious compared to the latter stages. Larvae are very numerous and disperse in large numbers and behave like ‘armyworm’. Insecticides are considered an important tool of FAW management as well as other lepidopteran maize pests. However, these practices are not sustainable and are linked to the environment, biodiversity and farmers' health. Alternative management strategies should be developed by understanding pest biology and ecology. Hence, a series of laboratory choice and paired-choice tests were conducted at Agriculture and Forestry University in May 2021 to evaluate the host plant preference by the fall armyworm. Potential host plants were Zea mays (maize cultivars - Rampur composite, Arun-2 and Rampur hybrid-10), Pennisetum purpureus (Napier), Oryza sativa (rice), Sorghum bicolor (Sorghum), Fagopyrum esculentum (Buckwheat), Vigna unguiculata (Cowpea) and Glycine max (Soybean). In choice tests, FAW preference was ranked as Rampur Composite > Sorghum > Rampur hybrid-10 > Arun-2 > Napier > Rice > Buckwheat > Cowpea > Soybean. Rampur composite and sorghum were the most preferred host plants, Rampur hybrid, Arun-2 and Napier were the medium preferred, rice was categorized as the low preferred and other host plants such as buckwheat, cowpea and soybean were the least preferred host plant of fall armyworm. In paired-choice tests, Rampur composite was more preferred than sorghum, but not significantly so. These research findings are useful to utilize in habitat manipulation strategies for fall armyworm management. Most preferred plant species can be deployed as trap crops and least preferred host plants can be used as repellent or push crops in a push-pull strategy. Such host plants in-and-around the main field can reduce the fall armyworm damage and reduce pesticide amount in main crops.

Maize farmers’ knowledge and management of fall armyworm (Spodoptera frupigerda) in southwest Nigeria

This study investigated maize farmers’ knowledge, control methods, and perception of the invasive and highly destructive insect pest, fall armyworm (Spodoptera frugiperda) in southwest Nigeria. A four-stage sampling procedure was employed in selecting 195 maize farmers in the study area. Data were obtained with the aid of structured questionnaire and analysed using percentages, means, standard deviations, and chi-square test. The majority (88.7%) of respondents observed fall armyworm attack within two months after sowing, only 30.8% of them reported total damage to maize plants by fall armyworm. Most (75.9%) of the respondents could describe the destructive larval stage of fall armyworm, 58.5% of respondents exclusively applied synthetic insecticides for fall armyworm management. The most common insecticides used by respondents were organophosphates (37.2%), pyrethroids (29.0%) and avermectins (18.2%). Perception of fall armyworm damage as a serious and worrisome problem was very high (4.82) amongst maize farmers. Strong and significant association (χ2 = 41.3) was found between farmers’ agroecological zones and the severity of fall armyworm damage reported. Integrated pest management approach is a sustainable alternative to the sole use of insecticides and should be promoted. Information provided in the study will enhance decision-making for fall armyworm management interventions in southwest Nigeria.

A Take-Home Message "Fall Armyworm Management in Asia and the Pacific Region"

A Take-Home Message "Fall Armyworm Management in Asia and the Pacific Region"- Y.D. GC

Fungal and viral entomopathogens as a combined strategy for the biological control of fall armyworm larvae in maize

BackgroundThe fall armyworm Spodoptera frugiperda is one of the major pests in maize crops, causing important production losses. The pest has rapidly spread worldwide, generating an urgent need to develop efficient and sustainable strategies for its control. In this work, the potential of integrating nucleopolyhedrovirus- (NPV) and the fungus Metarhizium rileyi to control S. frugiperda larvae was evaluated under laboratory, greenhouse, and field conditions.MethodsThe mortality of S. frugiperda larvae was evaluated after the application of NPV and M. rileyi alone or in combination using three concentrations (high, medium and low) under laboratory conditions. Then, two greenhouse trials using maize plants were carried out to evaluate the effect of individual or combined applications of NPV and M. rileyi on S. frugiperda mortality (first trial) and fresh damage (second trial). Finally, a trial under field conditions was conducted to evaluate the performance of the treatment selected in the greenhouse assay.ResultsThe combined use of NPV: M. rileyi applied simultaneously showed an additive effect in laboratory, causing higher larval mortality than the biocontrol agents used separately. This effect was evident in the mixtures using the concentration levels high:medium, medium:medium, and medium:high. Under greenhouse conditions, the use of a 50:50 ratio of the two entomopathogens also caused higher larval mortality and a significantly reduced insect damage to plants. Finally, under field conditions, the individual or sequential application of NPV and M. rileyi using 100% of their recommended doses, and the simultaneous application of both entomopathogens at 50% of their recommended doses, significantly reduced the recent foliar damage to levels under the threshold for economic losses (30% fresh damage) while the damage reached 43% when control measures were not used.ConclusionThe combined application of NPV and M. rileyi (two biocontrol agents with different mode of action) demonstrated an additive effect that allows to reduce to half their recommended application doses. In this context, the integration of both entomopathogens is a promising strategy to manage S. frugiperda, contributing to improve the economic feasibility of biological control tools for the sustainable fall armyworm management.

Seasonal difference in fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) abundance and plant injury on selected maize varieties in Ibadan, Southwest Nigeria

The fall armyworm, Spodoptera frugiperda J.E Smith, is a highly destructive insect pest of maize that first invaded Africa in 2016 and has since posed additional constraints to maize production and food security in the region. This study thus investigated the seasonal difference in the abundance of S. frugiperda egg masses and larvae on 25 maize varieties during the early and late planting seasons of 2018 and 2019 in Ibadan, southwest Nigeria. The relationship between larva abundance and foliar damage was also investigated at three-, five- and seven weeks after planting (3WAP, 5WAP, and 7WAP). Results showed that abundance was higher in 2018, in the early season, and at 3WAP. Though foliar damage occurred weekly in both seasons, the relationship between foliar damage severity and larva abundance at 7WAP was consistently weak and insignificant. Also, in both seasons, most of the observed kernel damage was caused by stem borer and not fall armyworm larvae. To make timely fall armyworm management decisions, regular field scouting, especially within the first three weeks after planting, is recommended.