As Gregor Mendel (1822–84) discovered by breeding peas in his monastery garden, certain traits in living organisms are inherited by means of genes (although he did not identify them as such). In the plant kingdom, selection for desirable traits by means of seed retention had been going on since the dawn of agriculture; and in the animal kingdom, farmers had long since worked out that you could breed for certain characteristics. Mendel’s work, and Darwin’s, had alerted the world to the possibilities of hybridization of plants and, as the science of genetics gained momentum during the early years of the 20th century, so the manipulation of the breeding of food plants took root. Much classical plant breeding matches the image of a scientist cross-pollinating his specimens with equipment no more threatening than a small paintbrush. As the search for higher yields and more disease-resistant varieties became more urgent, however, more extreme methods were deployed. These might include hybridizing distantly related species and rendering their infertile progeny fertile once more by treating it with colchicine, a toxic extract from the crocus. Or mutation of a plant’s genes might be induced by bombarding it with radiation. These facts are only noted as counterbalance to the criticism of genetic modification (GM) that it is ‘unnatural’. Some of the classical plant-breeders’ techniques were quite unnatural too.
