A new study published in the journal CABI Reviews highlights the critical role that integrated pest management (IPM) plays in combatting the threat fall armyworm poses to Asian rice security.
Asian rice production accounts for over two-thirds of global rice output but the region is highly vulnerable to the fall armyworm (Spodoptera frugiperda) which can threaten the food, nutrition and income security of millions of farming households.
The scientists say that rapid reproduction, extensive dispersal capabilities, and remarkable adaptability pose significant risks, with the potential for substantial yield losses comparable to those observed in other crops including maize in Africa.
Concerning host shift of the corn-specialized fall armyworm strain
Dr Lekhnath Kafle, Associate Professor, Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, and Dr Ravindra Chandra Joshi, Senior Consultant of the Philippine Rice Research Institute, and Associate at CABI South-East Asia, say recent reports highlight a concerning host shift of the corn-specialized fall armyworm strain towards rice cultivation in Asia.
They stress that, beyond direct yield losses, fall armyworm infestations can lead to the excessive use of pesticides, posing serious threats to human health and environmental safety. Effective and sustainable fall armyworm management is crucial for ensuring long-term agricultural sustainability.
Dr Kafle said, "Control strategies encompass a diverse range of approaches, including cultural techniques, biological methods, chemical interventions, and habitat manipulation. The absence of rice varieties resistant to fall armyworm underscores the urgent need for accelerated development through genetic engineering.
"Cultural control practices, such as staggered planting, deep tillage, crop rotation with non-host species, and improved field sanitation, can effectively reduce fall armyworm populations. While promising, methods like trap cropping and push-pull strategies require further field validation in rice systems.
"This review emphasizes the critical role of IPM in combating fall armyworm in Asia, advocating for a balanced approach that prioritises biological control, effective cultural practices, judicious use of insecticides, and sustainable agricultural methods to mitigate fall armyworm damage and ensure long-term rice security for the region."
Biological control measures utilize natural predators
The scientists say that biological control measures utilize natural predators, such as big-eyed bugs and ground beetles, and parasitoids like Telenomus remus and Campoletis sonorensis.
Additionally, entomopathogenic agents like Metarhizium rileyi, Bacillus thuringiensis (Bt), and Beauveria bassiana offer environmentally sustainable alternatives to chemical insecticides. While synthetic insecticides remain an essential component of fall armyworm management, the increasing prevalence of pesticide resistance and associated economic losses necessitate a shift towards eco-friendly solutions.
They argue that the growing resistance of fall armyworm to multiple insecticide classes underscores the urgent need for robust resistance management strategies. This is further exemplified, they say, by the pest's adaptive capacity, prolific reproductive potential, and formidable migratory prowess, which necessitates research into the intricate interactions between the fall armyworm and rice crops.
Dr Joshi said, "Unravelling the complex interplay of host plant resistance, insect behaviour, and population dynamics within rice agroecosystems is paramount for the development of robust and effective management strategies.
"By prioritising research and implementing IPM approaches, the agricultural community can effectively mitigate the devastating effects of fall armyworm on rice yields and safeguard the stability of global food supplies."
One possible avenue for future research and development, the scientists say is harnessing the power of the microbiome. They say that microbiome manipulation for enhanced biocontrol is promising as it focuses on optimizing the rice plant microbiome to promote bacteria and fungi capable of suppressing fall armyworm populations.
This could involve the introduction of specific beneficial microbes or the stimulation of the growth of native microbial communities.
Another prospect is enhancing biological control agents which are the cornerstone of fall armyworm management. This involves, the scientists say, using existing biological control agents such as parasitoid wasps and entomopathogenic fungi.
Additional information
Main image: The fall armyworm poses a significant threat to Asian rice security (Credit: Philippine Rice Research Institute).
Full paper reference
Lekhnath Kafle and Ravindra Chandra Joshi, 'Fall armyworm threatens Asian rice security: A review of sustainable management practices,' CABI Reviews, 19 March (2025). DOI: 10.1079/cabireviews.2025.0017
The paper can be read open access from 12:00hrs UK time 19 March 2025, here: https://www.cabidigitallibrary.org/doi/10.1079/cabireviews.2025.0017
