The Hunt for a Pest

ST. LOUIS (DTN) -- The Old World bollworm may be mere inches in size, but the U.S. is scaling up resources to detect and prepare for its likely arrival in American fields.

The pest, known formally as Helicoverpa armigera, made an unwelcome debut in Puerto Rico in September 2014. Since then, USDA's Animal and Plant Health Inspection Service (APHIS) has dedicated more than $1.2 million in 2015 to detection and control efforts in the U.S. The funding represents a twelvefold increase from funds allotted to the pest in spring 2014, when the bollworm had only been detected in more distant regions of South America.

As the government races to keep the Old World bollworm at bay, Monsanto is preparing to ramp up the planting of its new Bt-soybean product on U.S. soil for seed production. The product contains two Bt proteins targeting soybean pests such as the looper, velvetbean caterpillar and the Old World bollworm. It could be launched in the U.S. as early as the end of the decade, company representatives said.

The Old World bollworm is a serious pest in Europe, Africa, Asia, Australia, and most recently, South America. It has an enormous appetite for more than 180 species of plants, including corn, soybeans and cotton. A 2013 international study estimated that it costs growers more than $2 billion annually in global crop damage.

In March, an international group of government and university scientists concluded "the rapid spread of H. armigera through South America into Central America suggests that its spread into North America is a matter of time." Up to $78 billion worth of crops would be vulnerable to the pest in the U.S., the scientists added, and eradication would not be an option.

KNOW YOUR ENEMY

U.S. farmers possess some tools to battle the Old World bollworm, namely insecticides and Bt-traited crops. However, the pest has rapidly evolved resistance to most insecticides used against it and some Bt proteins, as well. As a result, analyzing the origins and pesticide resistance of the Puerto Rican specimens is a priority, USDA APHIS entomologist and risk analyst Dan Borchert told DTN.

Only 20 bollworm moths have been captured in Puerto Rico since September 2014, Borchert noted. So far, genetic analyses by scientists from Australia's Commonwealth Scientific and Industrial Research Organization (CSIRO) have determined that two of the moths possessed double copies of a gene found in the Brazilian pests, which themselves came from Asia. A third moth possessed genes of both Asian and African origin. Perhaps most importantly, the scientists have detected the presence of the gene involved in pyrethroid resistance, a fairly common type of insecticide resistance in the Old World bollworm.

With the pest's likely ability to resist many pesticide options, part of USDA's funding has been directed to alternative pest control tactics. A pest management company in California called Isca Technologies Incorporated received $185,000 from the agency to develop technology that would manipulate pheromones to disrupt the mating habits of the Old World bollworm. The technology would be tested in Brazil and then registered for use in the U.S. if it is successful, Borchert said.

CATCHING THE PEST

Much of USDA's funding for the bollworm is dedicated to finding it as quickly as possible as it spreads. Scientists have zeroed in on Florida as the most likely source of a mainland invasion.

The Florida Department of Agriculture and Consumer Services received nearly $118,000 in funding to survey regularly for the pest. An additional $85,800 was supplied to the University of Florida to develop and then teach methods to detect and identify the Old World bollworm, as well as distinguish it from its American cousin, the corn earworm (Helicoverpa zea).

The largest chunk of USDA's bollworm funds -- nearly $692,000 -- will go to efforts in Puerto Rico to aggressively survey and respond to the Old World bollworm populations there.

The rest of the USDA funding has been dedicated to a new detection technique called "real-time PCR," which could shrink the timespan needed to genetically confirm an Old World bollworm specimen. USDA doled out nearly $102,000 to Colorado State University researchers and an additional $34,500 to APHIS Plant Protection and Quarantine scientists in Texas to continue research on this technique.

BT BEANS ON THE WAY?

Monsanto's Bt soybean product, called Intacta, has been deployed in Brazil and Argentina for the second year in a row. As harvest gets underway on 15 million acres of Intacta beans, they appear to have held up well against the Old World bollworm, said Scott Bollman, Monsanto's insect platform lead for soybeans and cotton.

Intacta contains only a single Bt-protein, which makes it vulnerable to resistance development given the lack of refuge requirements in South America. Monsanto has so far ensured 95% compliance in the planting of 20% refuges, but that will become more challenging when acres swell to an expected 30 million in 2016, Bollman said.

With this in mind, the company is working on a second-generation, two-protein product that could be introduced in South America as early as 2018 and 2019. The U.S. is also a target for this new Bt soybean product, and the recent spread of the Old World bollworm could make it more attractive to U.S. farmers, Bollman noted.

The new soybean trait is not yet approved in the U.S. for cultivation, but the company has been approved to grow a limited number of acres for seed production for breeding and testing. Most recently, Monsanto has applied to the EPA to increase that number of acres in time for the 2016 planting season. "It doesn't take long to use up acres when you're running tests across multiple environments and against multiple pests," Bollman said.

Bt soybeans in the U.S. aren't a sure thing just yet. Monsanto is launching a third year of university studies to determine what role soybeans play as a natural refuge for Bt cotton in the South. The company doesn't want to bring Bt beans to market until they are sure they won't disrupt the planting of Bt corn and cotton there, Bollman said.

Dow AgroSciences is also planning to launch a two-protein Bt soybean product called Conkesta in South America, but the company has said it has no current plans to bring the trait to the U.S.

You can see and comment (up to April 17) on the EPA proposal to register Monsanto's Bt soybeans for a larger number of acres here: http://1.usa.gov/…

You can read more about scientists' expectations of a U.S. invasion by the Old World Bollworm here: http://1.usa.gov/…

You can find USDA's current funding for the Old World bollworm in Farm Bill Section 1007: Fiscal Year 2015 Spending Plan: http://1.usa.gov/….

Emily Unglesbee can be reached at emily.unglesbee@dtn.com

Follow Emily Unglesbee on Twitter @Emily_Unglesbee

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