Unlike us, plants have ample self-control when it comes to choosing how much they eat. Ironically, as humanity struggles with an obesity epidemic, plant breeders are trying to make crops eat more.
When you see a field of wheat in summer, the spikes of grain rippling gracefully in the breeze, you probably won’t have guessed that the plants are fat. Yet, compared to the wild grasses they are bred from, the ears of modern cereal plants are grotesquely obese. They have larger and more numerous grain, laden with vast reserves of starch, way in excess of what they actually need. This excess weight is our food.
With year-on-year gains from conventional breeding beginning to peter out and an ever-expanding human population to feed, the race is on to find new ways to persuade plants to put on even more weight. And it turns out that an effective way to do this is to interfere with the signalling systems that control the rate at which plants synthesise their food.