Wild corn is sorry looking stuff. It’s hard to tell it from a weed at first glance and, as University of Cambridge plant scientist Jim Haseloff points out, that’s not a surprise. “Most crop species are weedy species that have been through selective breeding processes over the past 10,000 years,” he says.
The Earth is host to some 20,000 known edible plant species out of an estimated quarter million species in total. Of that 20,000 a mere 10 per cent are grown in any volume by farmers. And just three account for the bulk of the biomass we actually eat, says Haseloff: rice; corn; and wheat.
Genetically, there is not very much difference between wild corn and what farmers plant today, even after the revolution in yields provided by hybrid corn and other crops developed during the Green Revolution of the mid-20th Century. It may seem churlish to make this point but plants are quite inefficient at converting sunlight and carbon dioxide into the carbon skeleton needed to grow roots and leaves. RuBisCO, a protein complex that lies at the heart of the photosynthesis process, is notoriously inefficient as an enzyme, although some researchers argue that RuBisCO is about as good as it can get.