By Tom Evans
In many peoples opinion, pesticides were one of the great tragedies of 20th century agriculture. They symbolized man’s dominance over nature: of the synthetic taming the organic – a cruelly ironic leitmotif of the modern world. In our post-Green Revolution era, most agricultural scientists see pesticides as anathema. Not only do they destroy the land and its biodiversity, but they also apply selection pressure onto insects to evolve resistant strains. The focal challenge of contemporary agriculture, then, is to devise new ways we can tame nature without inadvertently breeding resistance, or further damaging our precious ecosystems.
A recent paper in Nature Communications is part of a global effort to do just that. And, unsurprisingly, the answer comes through working with – not against – nature. A team of researchers from Kansas State University has genetically engineered a species of tobacco to produce chemicals known as pheromones. Plants do not usually make pheromones; in fact, they’re chemicals that insects produce, and they are usually involved in the communication systems of insects. For example, female silkmoths attract mates by producing a pheromone called bombykol. Male silkmoths can smell thispheromone from up to 10km away and follow the scent trail until they locate the female producing it.
So why has this group of scientists created a plant that makes pheromones?
The idea is we can harvest pheromones from plants and then use these natural chemicals in fields to control insects. At the moment industrially producing pesticides is bad for the environment, as well as the health of those working in pesticide factories. It’s also quite costly. By genetically engineering plants to synthesize pheromones, a so-called “plant factory” for pheromones could theoretically be established in the future, providing an environmentally friendly and cheap form of pest control. And moreover, the message is clear: nature is not our enemy, but our closest ally.