Farmers will soon have access to a novel technology to fight corn rootworm, a devastating pest that has grown resistant to traditional pesticides.
The Environmental Protection Agency on June 14 approved for sale four new corn seeds from Monsanto Co. and Dow Agrosciences engineered with ribonucleic acid interference (RNAi). The technology works by “silencing” certain genes from expressing undesirable traits. In the case of the companies’ SmartStax PRO seeds, the corn plants produce a pesticide that suppresses a gene that allows the worm to survive.
“We are using innovation and emerging technologies to solve problems like infestations of corn rootworm on our nation’s corn crop,” EPA Administrator Scott Pruitt said in a statement. “Corn rootworm has been called the ‘billion-dollar pest’ because it is so expensive for corn growers to control.”
Corn growers have struggled to address corn rootworms that don’t die from the insecticide Bacillus thuringiensis (Bt). Almost 80 percent of corn plantings in the U.S. are genetically engineered with Bt.
The seeds are the first to combine three modes of action against corn rootworm—two Bt proteins and the RNAi molecule.
Plant geneticists and farmers tout RNAi technology as a promising alternative to other forms of plant genetic engineering, which takes genes from one species and inserts them into another. This genetic modification has generated considerable controversy over the past three decades, but RNAi technology has also raised concerns.
Some environmental and health groups have raised the possibility that the technology could unintentionally shut off gene function in those who eat the foods, or could have ecological consequences past the limits of a farmer’s field.
In a statement, Dow Agrosciences backed the safety of its new product.
“EPA has thoroughly reviewed the environmental and human health risks of this product,” spokesman David Sousa said in an email.
The Food and Drug Administration in 2015 approved two crops made with RNAi techniques—an apple that resists browning and potatoes that produces less acrylamide, a carcinogen. An EPA Scientific Advisory Panel in 2014 more research to better assess the health and ecological implications of using the technology.