Reducing risks of an absoluta disaster for tomato producers in Southeast Asia

The South American tomato leaf miner, Phthorimaea [Tuta] absoluta, is a very serious insect pest of tomatoes in both open field and protected cultivation that can completely destroy a crop if left uncontrolled. Spreading rapidly eastwards across Europe, Africa, and Asia over the past 15 years, it is now on the doorstep of Southeast Asia – for the moment…

Invasion into new areas follows several potential pathways. These are movements from infested areas of tomato fruit, containers, packaging, and vehicles to seedlings of tomato or other Solanaceous crops and ornamentals. Thus, implementing effective quarantine procedures during international trade is a key means to reduce the risk of spread across borders.

The march and impact of the tomato leaf miner

It was first recorded in Peru in 1917 and, by the 1990s, was found in all South American countries. It jumped the Atlantic to Spain in 2006 and, in just three years, the whole Mediterranean basin. Europe was conquered in 2011. In Asia, it spread from Israel, Jordan, and Turkey (2009) to Iran (2010), India (2014), Bangladesh (2016), and China (2017), despite every effort to stop it.

Larvae bore through growing points, leaves, and stems, killing young plants, damaging fruit, and causing secondary infections. Larvae also make a distinct blotch mine on leaves. In Brazil, farmers sprayed almost daily to try and control it. And in the Netherlands alone, economic losses are estimated to between €5 to €25 million per year.

As P. absoluta is a new insect pest in Southeast Asia, information on it was limited. So, thanks to funding from the government of Japan, WorldVeg initiated a project to provide key knowledge required in pest quarantine and improve regional cooperation between member countries of the Association of Southeast Asian Nations (ASEAN) to establish pest surveillance at possible ports of entry where the pest has not yet been reported.

In December 2022, WorldVeg hosted 27 quarantine officers from all ten ASEAN member states: Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand and Vietnam. Over two weeks at its East and Southeast Asia research and training station on the Kamphaeng Saen campus of Kasetsart University, Thailand, they undertook intensive training on how to prevent the invasion of the tomato leaf miner. They learned the importance of a proper phytosanitary process, inspection, monitoring, morphological and molecular identification of the insect in all its different life stages, main pathways for invasion, and management strategies when the pest arrives.

Then, with technical support from WorldVeg experts, ten country risk assessments and ten surveillance protocols were developed based on each country’s particular requirements and data gathered during the training. A demonstration plot was organized to show integrated pest management approaches for controlling P. absoluta and to support rapid response once the insect pest is detected in any ASEAN member state. For improved surveillance, 250 pheromone lures were provided for five countries where an import permit is not required: Brunei, Laos, Indonesia, Myanmar, and Singapore. Based on the training received, Indonesia rolled out similar training across the country.

To maintain communication, a WhatsApp platform was established to share and discuss surveillance results at regular intervals across the region. WorldVeg also keeps in active contact via the platform to provide technical support regarding pest identification and early detection of P. absoluta in high risk areas of participating countries. In 2023, typical symptoms of tomato leaf miner damage were found in Laos, and the material was sent to for analysis. All ASEAN member states stay on alert, but now thanks to this project, they are better armed to reduce risks from this potential new invader.

The ‘Improved coordination and strengthened capacity to deal with the invasive insect pest Tuta absoluta in mainland Southeast Asia’ project (2021-2023) was supported by the government of Japan through the Japan-ASEAN Integration Fund (JAIF).

This article can also be found in the World Vegetable Center Annual Report 2023

WorldVeg Annual Report 2023 ! – World Vegetable Center (avrdc.org)