Plant breeders are fast-tracking genetic improvements in food crops to keep pace with global warming and a growing human population, writes Knvul Sheikh in an article published in the New York Times yesterday.
Sheikh writes that farmers and plant breeders are in a race against time. The world population is growing rapidly, requiring ever more food, but the amount of cultivable land is limited. Warmer temperatures have extended growth seasons in some areas — and brought drought and pests to others.
“We face a grand challenge in terms of feeding the world,” said Lee Hickey, a plant geneticist at the University of Queensland in Australia.
Dr. Hickey’s team has been working on “speed breeding,” tightly controlling light and temperature to send plant growth into overdrive. This enables researchers to harvest seeds and start growing the next generation of crops sooner.
This is easier said than done for some crops. Potatoes and some other crops, such as alfalfa, are tetraploids, carrying four copies of each chromosome. (Humans and most animals are diploid, with two chromosomes, one from each parent). A breeder might want to delete one gene that decreases crop yield, but there may be three more copies of the gene on the plant’s other chromosomes.
This unique inheritance pattern means that potatoes are typically sterile, and must be propagated by harvesting them and replanting tubers. Speed breeding and genetic editing can only fast-track propagation to a certain extent, said Benjamin Stich, a plant geneticist at the Heinrich Heine University of Düsseldorf, Germany.