PARIS — Roundworms defend palm trees against red palm weevils, and minute wasps protect corn against European corn worms. Using natural tiny warriors to preserve agricultural fields is known as biological control, or biocontrol. And this method is working its way around the world.
Today, less than 5% of cultivated lands are protected this way, but the practice is growing and is expected to increase over the next five years. “These eco-friendly products have proved they are effective,” says Jean-Pierre Princen, president of the French branch of the International Biocontrol Manufacturers’ Association (IBMA). “We noted the enthusiasm of big companies that produce chemical pesticides because they actually invest in this sector.”
InVivo, which is the first French farming cooperative, distributes pesticides but also produces its own insects with its Biotop branch. InVivo development manager Antoine Poupart says the “two methods must be used in a complementary way.”
Biocontrol has already seduced the biggest chemical corporations such as the Germany’s Bayer or the U.S.-based Monsanto. Swiss-based Syngenta created the Bioline range 25 years ago. “In the Netherlands, Spain and France, they protect tomatoes under greenhouses by using 70% biocontrol and only 30% classic pesticides,” says Gérard Thomas, technical manager of Syngenta.
For the experts of the French Institute of Research for Development (IRD), biocontrol is a major issue. “Despite the increasing use of pesticides since the 1960s, the rate of harvest loss stays high: between 40% to 50% in emerging countries and 25% to 30% in industrialized countries,” the Institute notes.
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Lady bugs are commonly sold for biological control of greenflies — Photo: Dekayem
Imported from Central America 20 years ago, the Guatemalan moth ravages the potato fields in Venezuela, Colombia and Ecuador. According to IRD researcher Olivier Dangles, this moth can “eat up entire stocks of potatoes, which are one the main crop” and staple there. “Some means exist to fight them back, but they are either toxic or financially out of reach for the farmers,” he says.
The IRD and its Ecuadorian partners developed a biopesticide from a virus that contaminates the moths. But Dangles says the priority is to train the farmers and organize campaigns to educate them.
Expensive and hard to use
Plus, the use of biocontrol in the fields remains tricky. “The insects can be blown away by the wind or they can just leave,” Thomas says. “These living tools require sharp surveillance.”
The use of biocontrol is often quite expensive, which explains its slow development. According to Syngenta, producing living organisms requires expensive technical skills and a complex system of transportation. “It is difficult to stock and transport these living organisms because they have precise dates of use,” says Laure Kaiser, who works for the IRD but is also a researcher for the French National Center for Scientific Research (CNRS).
Whether they be insects or virus, these initiatives remain delicate. “If we want to destroy plant bugs coming from other regions, we have to search for their predators in their countries of origin. But first we have to check if these predators can get used to the area. Then there is the problem of regulations that limit the introduction of exotic living organisms,” Kaiser explains.
IRD researchers have identified other obstacles to the development of biocontrol: lack of awareness among farmers, minimal financial advantages and the lobbying of agricultural chemistry industries.
The Chinese were already using predatory ants to preserve mandarin trees 3,000 years ago. Today, the IRD insists biocontrol needs to develop because the world could soon be home to nine billion people, and food could grow scarce. Says Jean-Pierre Princen, “It is necessary to change the ways of thinking and production.”
