In a fascinating long piece in MIT Technology Review, Antonio Regalado examines the genetically modified seed industry's latest blockbuster app in development—one that has nothing to do with seeds. Instead, it involves the industry's other bread-and-butter product: pesticide sprays. But we're not talking about the poisonous chemicals you convinced your dad to stop dousing the lawn with. The novel sprays in question are powered by a genetic technology called RNA interference, which promises to kill specific insects and weeds by silencing genes crucial to their survival, while leaving nontarget species unscathed.

RNAi, as it's known, is an emerging science; the two US researchers who discovered it brought home a Nobel Prize in 2006. Regalado describes the process like this:

The cells of plants and animals carry their instructions in the form of DNA. To make a protein, the sequence of genetic letters in each gene gets copied into matching strands of RNA, which then float out of the nucleus to guide the protein-making machinery of the cell. RNA interference, or gene silencing, is a way to destroy specific RNA messages so that a particular protein is not made.

If you can nix RNA messages that exist to generate crucial genes, you've got yourself an effective bug or weed killer. And GMO seed and pesticide behemoth Monsanto thinks it has just that. Robb Fraley, the company's chief technology officer and a pioneer in creating GM seeds, told Regalado that within a few years, RNA sprays would "open up a whole new way to use biotechnology" that "doesn't have the same stigma, the same intensive regulatory studies and cost that we would normally associate with GMOs." Fraley described the novel technology as "incredible" and "breathtaking."



It's not hard to see why the veteran agrichemical and biotech exec is so amped for something new to load into a crop duster. Monsanto's GM herbicide-resistant and insecticidal traits still dominate the highly lucrative US corn, soybean, and cotton seed markets, but these cash-cow products are victims of their own success, so widely used that weeds and pests are rapidly developing resistance to them. The company's flagship herbicide, Roundup, still generates about $5 billion in sales annually, but it went off-patent years ago, and it was recently declared a "probable carcinogen" by the World Health Organization—a finding Monsanto disputes.