Beneficial Insects & Natural Enemies
The good guys - insects and natural enemies that help control FAW
Source: Istock
The Fall Armyworm (Spodoptera frugiperda) is a destructive pest that significantly impacts important crops, such as maize, in Southeast Asia. To manage this pest sustainably, researchers are exploring potential natural enemies in the region that could help control its spread. These natural enemies include predatory insects such as beetles and wasps, parasitic species, predatory mites, and various microbial pathogens such as fungi, bacteria, and viruses that can infect and kill the pest.
In its native regions of the Americas and the Caribbean, over 150 species that naturally prey on or parasitize the Fall Armyworm have been identified. As this pest has spread across Southeast Asia, researchers in countries like Indonesia, the Philippines, Thailand, Vietnam, and Malaysia are actively studying local ecosystems to discover similar beneficial organisms that could serve as effective biological control agents.
This page highlights the studies on the potential natural enemies and predators of Fall Armyworms in Southeast Asia.
Predators of fall armyworm reported from Southeast Asia
Most predators of the Fall Armyworm (Spodoptera frugiperda) are generalist species, meaning they also feed on a wide variety of other caterpillars and insect pests. In Southeast Asia, several arthropod predators that target the Fall Armyworm have been documented.
To date, 16 species have been reported in Indonesia, while four species have been identified in Malaysia. In Indonesia, researchers have found a diverse group of natural enemies, including five species of ants (Rizali et al., 2021), four species of lady beetles (Ginting et al., 2020; Rizali et al., 2021), one species of earwig (Tarigan et al., 2023), and six species of spiders (Rizali et al., 2021; Tarigan et al., 2023). Although these predators are not specifically focused on the Fall Armyworm, their presence in the field helps to naturally suppress the pest.
A list of the predators that have been recorded in Indonesia:
Ants
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Anoplolepis gracilipes
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Dolichoderus sp.
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Pheidole sp.
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Polyrhachis sp.
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Tapinoma sp.
Earwig
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Doru sp.
Pic 1. (a) Earwig, (b and c) fall armyworm eggs and larvae attacked by earwig, ( d and e) fall armyworm larvae attacked by ants.
Source: Ahissou, et al., 2021
Lady beetles
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Coleomegilla maculate (De Geer)
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Harmonia sp.
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Menochilus sexmaculatus (F.)
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Micraspis discolor
Spider
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Oxyopes sp.
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Amaurobiidae sp.
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Clubionidae sp.
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Gnaphosidae sp.
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Lycosa sp.
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Miturgidae sp.
Pic 2.(f) Fall armyworm larvae attacked by lady beetle (g) spider on maize plant
Source: Ahissou, et al., 2021
Species reported from Malaysia include 1 lady beetle, 1 rove beetle, and 2 pentatomid bugs (Jamil et al. 2021)
Pentatomid bugs
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Andrallus spinidens (F.)
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Eucanthecona furcellata (Wolff)
Beetles
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Micraspis discolor (F.)
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Staphylinidae sp.
Pic 3. Staphalinid sp. adult
Source: Shepard, Carner and Ooi
Pic 4. Pentatomid predator eating a larva
Source: Ahissou, et al., 2021
Parasitoids and potential biocontrol of Fall Armyworm in Indonesia
Species diversity and abundance of parasitoids study of fall armyworm in Indonesia
The presence of parasitoids of S. frugiperda (Fall Armyworm) has been reported in some regions of Indonesia. Species that have been confirmed to attack Fall Armyworm are listed below:
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West Sumatera province: Microplitis sp., Chelonus sp. (Sari et al., 2023)
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Nusa Tenggara Barat province: Apanteles spp., Eriborus spp., Exorista spp. (Supeno et al., 2021)
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South Sumatera province: Chelonus formosanus Sonan, Chelonus oculator F., Chelonus annulipes Wesm., Chelonus cautus Cresson, Microplitis anila Ashmead, Microplitis, marshallii Kokujev, Euplectrus corriemoreauae Hansson, Compsilura concinnata Meigen, Sarcophaga sp., Macrocentrus sp., Exorista sp., and Megaselia sp (Herlinda et al., 2023)
Pic 5. Species of egg and larval parasitoids of Spodoptera frugiperda: A) Telenomus remus(Nixon), B) Chelonus formosanus Sonan, C) Chelonus annulipes Wesm., D) Chelonus oculator F. ,E.) Chelonus cautus (Cresson) F.) Microplitis manilae Ashmead, G). Microplitis marshallii Kokujev, H) Euplectrus corriemoreauae Hansson, I) Compsiluracon cinnata (Meigen)
Source: Herlinda et al., 2023
Research on the rate of parasitization by local parasitoids on Fall Armyworms in three different corn ecosystems
A recent study by researchers from Gadjah Mada University (Wahyuningsih et al., 2021) investigated the potential of native parasitoids as biological control agents against the Fall Armyworm (FAW) in Indonesia. The research focused on two egg parasitoids, Telenomus remus and Trichogramma sp. and their effectiveness across three corn-growing ecosystems in East Java: agroforestry, rice fields, and rainfed fields.
Key Findings of the study:
Pic 6. Telenomus remus, parasitizing fall armyworm eggs. Source: ICIPE
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Egg mass parasitization ranged from 15.6% to 52.5%, depending on the ecosystem and sampling time.
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Telenomus sp. was more abundant and effective than Trichogramma sp. in all locations.
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Agroforestry systems consistently showed the highest parasitization rates, followed by rice fields and then rainfed fields.Across all three ecosystems, parasitization rates on individual egg masses ranged from 43.7% to 81.6%.
Previous studies in other countries also indicate that both parasitoids have been effective in reducing infestations of Spodoptera frugiperda in the field, achieving parasitization levels ranging from 37.5% to 84.7% in Cameroon (Abang et al., 2021) and 64% in Nigeria (Laminou et al., 2020). Telenomus sp. was found more abundant in the three ecosystems (agroforestry, rice field, and rainfed field) than Trichogramma sp. This study confirmed findings from a previous study conducted by Herlinda et al., (2023) which found Telenomus remus nixon as the most abundant FAW parasitoid out of 14 natural enemies.
Parasitoids and potential biocontrol of Fall Armyworm in the Philippines
New record of natural enemies of fall armyworms in the Philippines
A sampling and monitoring study of the fall armyworm (Spodoptera frugiperda) and its natural enemies was conducted across six rice and corn-growing municipalities in Northern and Central Luzon, Philippines (Valdes et al., 2023). This led to the first identification of two new parasitoid species attacking the fall armyworm in the Philippines and globally. Molecular analysis conducted by CABI identified the two parasitoid species as Brachymeria lasus Walker (Chalcididae), which is a solitary pupal parasitoid, and Copidosoma floridanum (Ashmead), a larval parasitoid. While B. lasus has previously been reported to parasitize various Lepidopteran pests, this study provides the first evidence of its association with S. frugiperda (Valdes et al., 2023).
Another parasitoid was identified in a study by Calcetas et al. (2023): Chelonus formosanus Sonan is a parasitoid wasp species that was collected emerging from parasitized Spodoptera frugiperda larvae in the Philippines. This was the first record of C. formosanus in the country, expanding its known distribution beyond previously documented regions. Globally, ten Chelonus species are associated with FAW, most occurring in Central America, Africa, and Asia.
Pic 8. Female of Chelonus formosanus Sonan. A) dorsal, B) lateral. Source: Calcetas et al., 2023
A study by (Gupta., 2020) also confirmed that Chelonus formosanus can naturally parasitize Spodoptera frugiperda in maize fields and complete its life cycle under laboratory conditions, making it suitable for mass rearing. The parasitism rate ranged from 10% to 19.4%, with 45% to 57.5% of C. formosanus adults successfully emerging from their cocoons.
Pic 9. Chelonus formosanus: A) Larva emerging from the larva of fall armyworm, B) Larva feeding on the larva of fall armyworm
Source: Calcetas et al., 2023
Study on potential natural enemies of fall armyworm in Thailand
Study on the Efficacy of Thai indigenous entomopathogenic nematodes for controlling fall armyworm
A recent study assessed the effectiveness of two Thai Indigenous entomopathogenic nematodes (EPN) isolates: Heterorhabditis indica AUT 13.2 and Steinernema siamkayai APL 12.3 in controlling fall armyworm (FAW) under laboratory and greenhouse conditions (Wattanachaiyingcharoen et al., 2021)
In laboratory trials, six concentrations of nematodes (50–300 infective juveniles (IJs) per ml) were tested against second and fifth-instar FAW larvae. The results indicated that the second-instar larvae were more susceptible than the fifth instar. H. indica AUT 13.2 proved the most effective, achieving 83% mortality at 250 IJs per ml, while S. siamkayai APL 12.3 resulted in 68% mortality at 300 IJs per ml. The fifth instar larvae exhibited lower mortality rates, with H. indica AUT 13.2 achieving 45% and S. siamkayai APL 12.3 achieving 33% mortality at 250 IJs per ml (Wattanachaiyingcharoen et al., 2021).
Heterorhabditis indica
Photo credit : Kathy Halat
Source: USDA
In greenhouse trials, the concentrations were adjusted to 20,000 and 50,000 IJs per ml per pot, resulting in lower overall mortality rates than the laboratory conditions. The highest mortality observed was 58% with H. indica AUT 13.2 at 50,000 IJs per ml, followed by 45% for S. siamkayai APL 12.3 (Wattanachaiyingcharoen et al., 2021)
Parasitoids and potential biocontrol of Fall armyworm in Malaysia
Natural enemies of invasive pest Fall Armyworm in Malaysia
A field survey in Kedah identified two generalist predatory soldier bug species, Andralus spinidens and Eocanthecona furcellata, attacking Spodoptera frugiperda (fall armyworm) on grain corn farms. A single A. spinidens male and nine E. furcellata adults were collected and brought to the Entomology lab at MARDI Serdang. While E. furcellata was mass-reared for three generations, the colony eventually collapsed (Jamil et al., 2021)
Pic 11. Andralus spinidens (a) immature (b) adult
Source: Jamil et al., 2021
A feeding experiment confirmed that both soldier bug species pierced and consumed S. frugiperda larvae (instar 2 and above), but only E. furcellata was observed feeding on pupae. These preliminary findings suggest that E. furcellata may have potential as a biological control agent. However, further studies are needed to assess its life cycle, feeding behavior, and predation efficiency before considering its introduction in pest management programs (Jamil et al., 2021)
Pic 12. Eocanthecona furcellata (a) immature (b) adult (c) an adult feeding on a S. frugiperda pupa.
Source: Jamil et al., 2021
Enhancing pest management using predatory insects in Vietnam
Utilizing supplementary food spray to harness predatory insects against fall armyworm in maize crop of Vinh Phuc Province, Vietnam
Effective pest management in maize production requires strategies that minimize insecticide use while enhancing the role of natural predators. Generalist predatory insects play a significant role in controlling pests; however, their populations need support to maximize their effectiveness (Mensah et al., 2024)
One promising approach is using supplementary food sprays that attract and sustain natural predators, improving their ability to manage pests such as the fall armyworm (Spodoptera frugiperda).
A study by Mensah et al. (2024) examined the potential of food spray formulations to attract and maintain beneficial insect populations in Vietnamese maize fields. They developed a novel, locally sourced formulation called the "Vietnam Food Product" (VFP), a cost-effective and farmer-friendly alternative to chemical pest control.
The results indicated that VFP significantly increased the abundance of predators, leading to a notable reduction in fall armyworm populations. Notably, the plots treated with food sprays achieved a higher net margin of $3,467 compared to $3,394 for conventional insecticide-treated plots, emphasizing the economic viability of this approach. Additionally, the study recorded an average predator-to-prey ratio of 9.2:1 in the food spray-treated fields, which proved sufficient for the long-term suppression of the fall armyworm throughout the season (Mensah et al., 2024)
Insect pathogens and beneficial insects recorded in Laos
Insect pathogens
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Beauveria bassiana
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Nomuraea sp.
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Nuclear Polyhedrosis Virus (NPV)
Pic 13. Insect of FAW Larvae: affected by (a ) Nomuraea sp, (b) Beuveria bassiana and (c) Nuclear Polyhedrosis Virus (NPV).
Source: Soysouvanh et al., 2021
Insect Predators
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Stink bug (Eocanthecona furcellata)
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Assassin bug (Rhynocoris sp.)
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Assassin bug (Sycanus collaris)
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Assasin bug
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Earwig
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Lady beetle
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Spider
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Tiger beetle
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Ants
Parasitoids
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Charops sp.
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Chelonus sp.
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Cotesia sp
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Microplitis sp
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Telenomus sp.
Pic. 14. Predators: (a) Stink bug (Eocanthecona furcellata), (b) Assassin bug (Rhynocoris sp.), (c) Assassin (Sycanus collaris), (d) Assassin bug
Source: Soysouvanh et al., 2021
Pic. 15. Predators: (e) FAW larva being eaten by ants, (f) earwig, (g) lady beetle, (h) FAW moth eaten by spider, and (i) tiger beetle
Source: Soysouvanh et al., 2021
Further Resources