Tomato crop

Dr. Muniappan works in a tomato field in northern Senegal with a local farmer.

A devastating tomato leafminer, Tuta absoluta, wipes out 80 percent of Nigeria’s tomato crop. The BBC and Bloomberg’s international news operation devote hours of broadcast time and inches of news stories to explaining the pest.

One place media coverage has gaping holes: the United States. This is unfortunate because worldwide, since 2006, the pest has wormed its way into Costa Rica, Egypt, France, Israel, Italy, India, Kenya, Libya, Russia, Spain and almost 50 other countries.

Some scientists — myself included — believe that the leafminer that destroyed Nigeria’s crop will eventually show up in the United States. And when it comes to invasive pests like this tomato leafminer, awareness and preparedness are key.

Virginia is one of the top five states most vital to fresh-market tomato production, along with the powerhouse producers, California and Florida. The threat this leafminer poses deserves more headlines than it commands so that monitoring, preparation and controls can be put in place.

A Bloomberg story, for instance, quotes Richard Hopkins, head of pest behavior at the London-based University of Greenwich’s Natural Resources Institute: “Tuta (absoluta) has the potential to effectively eliminate tomato from the agricultural cycle.”

Eliminate tomatoes? The Virginia public’s attention is crucial, along with that of scientists and policymakers. Awareness can lead to action. Fortunately, we can do more than just sit back and witness the devastation of our crops. (Or, like some of the affected countries, launch futile attempts to eradicate the pests through poison alone.)

At the Virginia Tech-headquartered Integrated Pest Management Innovation Lab, we seek to curtail agricultural pest problems with an emphasis on natural — as opposed to toxic chemical — means. Our research-and-education protocol has produced some recent evidence of this approach’s effectiveness.

For example, in East Africa, farmers and scientists learned and adopted integrated-pest-management practices, which they then deployed against multiple problems impeding healthy tomato crops. As a result, tomato yields increased from 54 percent to 268 percent, depending on the tactic put in place.

The East African countries not only experienced greater income, but they also learned a valuable lesson: Chemical pesticides can be harmful to human health and carry potential to kill the naturally existing antagonists of the very pests we are trying to eliminate. If you kill the predators that consume the pests, then the problem quickly spirals out of control.

This is a lesson that the U.S. agricultural community could stand to fully embrace, given its reliance on toxic, synthetic pesticides.

Our decade-long East African intervention wasn’t focused on Tuta absoluta. However, last year, our Innovation Lab directly addressed the pest through workshops in Nepal and Bangladesh, two countries we had identified as vulnerable to the pest’s invasion. The spread of Tuta absoluta to both countries occurred in June — again, with almost no media coverage making note of the event.

Scientists in Nepal and Bangladesh who attended the 2015 workshops have told us that what they learned made a difference. They were able to quickly identify the leafminer and institute controls. This is a heartening development. No one wants to see another tomato crop failure on the scale of Nigeria’s.

What’s happening in terms of U.S. government response? Based on our recommendations, and those of other scientists, the United States no longer allows imports from affected countries unless stems and leafy tops have been removed. And the federal government is helping states with monitoring through the use of pheromone traps. Another key element of the strategy is to help Costa Rica suppress the pest. Costa Rica is perilously close to home!

We can minimize the spread of this devastating tomato leafminer. But first we must understand that its arrival is all but inevitable. The time to prepare is now.

Muniappan is director of the Integrated Pest Management Innovation Lab at Virginia Tech, part of the Office of International Research, Education and Development, one of 24 USAID-funded labs working to reduce hunger worldwide. You may contact him at

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