The fall armyworm (FAW) is an insect pest that feeds mainly on maize and more than 80 other crops, including sorghum, millet, sugarcane, vegetables and cotton. It is a transboundary pest that can fly over 100 km in a single night and has a high reproductive rate of more than 1,000 eggs per female in its lifetime. The larval stage is the most devastating period with drastic yield loss, adversely impacting the overall economy. The pest is found to thrive in temperatures above 10 degrees Celsius, and the wings of moths are deformed above 30 degrees Celsius. Native to the Americas, FAW has been reported in more than 70 countries. In October 2019, the presence of the pest was confirmed in most Asian countries, including Nepal, China, Indonesia, India, Japan, Laos, Malaysia, Myanmar, South Korea, Sri Lanka, Vietnam, Cambodia and the Philippines.

This pest can cause considerable yield losses and threaten food security and the livelihoods of hundreds of millions of smallholder farmers and consumers. It causes damage in both quantity and quality. In the Asia Pacific region, the damage is at various levels. It is low and medium 5 to 40 percent in Nepal, depending on the season. With maize being a vital food and feed crop, the damage caused by FAW directly impacts national economies, leading to global food insecurity, malnutrition and poverty among smallholder farmers.

Another major problem associated with FAW infestation is the increased use of hazardous pesticides. Significant challenges faced by countries in mitigating FAW damage include, among others, inadequate coordination, ineffective monitoring and control techniques, lack of alternatives to chemical pesticides and ineffective phytosanitary measures and low capacity to deal with the pest at the national level. Strong emphasis should be placed on limiting the pest dispersal and control rather than eradication.

Key actions

As a robust response to FAW’s rapid spread, the FAO (Food and Agriculture Organisation) launched global action on FAW Control (GA, 2020-2022) in December 2019, aiming at promoting FAW control at the global, regional and national levels. In the Asia and Pacific region, FAO Regional Office for Asia and the Pacific organised an international conference in Bangkok, Thailand in March 2019 and brought together relevant scientists and practitioners to share their knowledge and experiences and help the region prepare for the continued spread of FAW in Asia.

In early August 2020, ASEAN approved a FAW action plan. In this connection, chaired by the assistant director-general of FAO Regional Office for Asia and the Pacific, a regional steering group consisting of 32 FAO member countries was established in June 2020. It has focused on building capacities of the National Plant Protection Organisations in coordinating and facilitating technical and experience exchange programmes through virtual training activities with an emphasis on preparedness; establishing early warning systems for monitoring and early actions to prevent wider spread of the pest; implementing of integrated pest management for sustainable management measures, and importantly anchoring the response around smallholder farmers. Importantly, the FAO regional office has also supported emergency and technical cooperation projects in the countries concerned.

As FAW continues to spread, the FAO regional office stands ready to help member countries deal with its possible threats, focusing on early actions, monitoring and learning lessons from other regions, further strengthening the community of international experts, developing regional national plans of action, and identifying current knowledge gaps to decide on research priorities, as well as working closely with farmers and their organisations. The immediate top priority is the development of regional integrated pest management packages in demonstration countries (including China, India and the Philippines) to be used and implemented by 15 pilot countries in the region. The FAO regional office has also supported technical cooperation programmes in China, Laos, Pakistan, Vietnam and Indonesia in Asia, as well as the Solomon Islands, Fiji, and Vanuatu in the Pacific in the areas of both programme formulation and implementation.

Key results

Considerable efforts have been devoted to limiting the spread of FAW within the countries concerned as well as the transboundary movement. One of the key achievements is the institutionalisation of the programmes in the government systems through the establishment of national task forces. In Nepal, a national responding body has been undertaken under the chair of the joint secretary level, showing greater ownership of the work. These bodies provide oversight for the development of action plans and the implementation of various integrated pest management programmes in the countries. Emphasis is placed on the do-how approach along with the know-how. As a result, some countries have successfully contained the spread of the pest and limited dispersal to a considerably low level.

However, in Nepal, such a significant impact has not been reported, but low pest dispersal has been found. Excellent foundations have been laid, where the rearing of natural enemies in the Provincial Plant Protection Laboratories is undertaken. Similarly, knowledge products and citizen science-based technology dissemination with the support of the provincial ministries and Agricultural Knowledge Centres are crucial.

The improvements in the working staff and farmers’ functional capacity by implementing integrated pest management programmes and programmatic interventions are critical to these results. In India, farmers largely favoured synthetic pesticides and chose relatively lower-priced pesticides compared to new generation insecticides that were highly effective against FAW. Despite the benefits, farmers’ frequency of pesticide application increased significantly over the period.

In this regard, discouraging the widespread use of highly hazardous chemical pesticides should be given continuous focus. Emphasis needs to be placed on the selection and use of synthetic as well as locally produced, cost-effective and eco-friendly homemade bio-pesticides, which are also affordable to farmers. In the future, these programmes need to incorporate the following: First, assessment of preferred crop varieties for resistance or tolerance to FAW; second, use of inoculative biological control as well as bio-pesticides; and lastly, continuous support in the implementation of phytosanitary and bio-security measures backed by a conducive policy environment.