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Plant breeding has come a long way.

When the famed agronomist Norman Borlaug was developing his rust-resistant wheat variety in mid-20th-century Mexico, he lacked the detailed understanding of DNA’s role in heredity that we have today. Instead, he based his work on observed traits, crossing plants with desired characteristics and hoping their offspring developed the best features of both parents. It was imprecise and arduous work.

In The Wizard and the Prophet, a book that includes a biography of Borlaug, the American journalist Charles C. Mann writes:

“Genetically speaking, high-volume crossbreeding is equivalent to throwing a huge number of darts, in the belief that chance will eventually produce a bull’s-eye. High-volume crossbreeding was typically the province of big laboratories with large staffs. Borlaug and his small team would have to sow and raise thousands upon thousands of wheat plants, collect each plant’s pollen individually, hand-pollinate the blossoms, harvest the resultant grain plant by plant, and then grow that grain to discover the results of their crossbreeding.”

Using this method, creating a cultivar that was physically robust, high-yielding, and rust-resistant took Borlaug around 20 years.

Since then, our understanding of genetics and heredity has become much more sophisticated, resulting in new breeding strategies and tools. Rather than selecting plants based solely on observed traits, today’s breeders can check the genome for molecular markers associated with certain characteristics. With CRISPR, they can even edit the genome directly. Last week, David Friedberg, the CEO of a startup named Ohalo Genetics, announced an innovative approach to plant breeding he calls “Boosted Breeding” that uses genetic modification to take advantage of a condition called polyploidy.

Polyploids are organisms with more than two sets of chromosomes. They’re more common than you might think—scientists estimate somewhere between 30 and 70 percent of flowering plants are polyploids. Examples include common wheat, with six sets of chromosomes, and strawberries, with eight. Polyploidy is interesting to plant breeders because it can be artificially induced to change a plant’s traits. Typically, breeders induce polyploidy with certain chemicals, such as colchicine or oryzalin, that cause the chromosomes in plant cells to duplicate. This extra DNA can have powerful effects on the plant, from increasing cell size and overall plant vigor to enhancing resistance to diseases and pests. Several commercial crops, from seedless melons to triticale wheat, were produced using this method.

Ohalo’s process is different. Rather than making an existing plant into a polyploid, the startup claims they can tweak a plant’s reproductive system using “novel proteins and techniques.” Instead of passing just 50 percent of its genes to the next generation—like in normal sexual reproduction—the edited plant transfers its entire genetic code. If two of these edited plants breed, their offspring inherit the combined chromosomes of each parent.

Friedberg reports an impressive 50 to 100 percent increase in yields in the “boosted” offspring. He also claims that Ohalo’s breeding system can combine desirable traits more efficiently than other methods, and that it produces genetically uniform seed. The latter could be especially useful for potatoes, which are typically grown from cuttings due to the large amount of genetic variation in their seeds.

To help make sense of these claims, we reached out to Jesse Ausubel, an environmental scientist, Human Progress board member, and the Director of the Program for the Human Environment at The Rockefeller University. Ausubel described Ohalo’s work as an “exciting” exploration of polyploidy that may ensure rising crop yields “continue to pervade agriculture for a long time.” However, he cautioned against taking the reported yields at face value: “In the end, farm yields tend to rise not by leaps but by 2 to 3 percent per year because of the sum of constraints and inputs (water, fertilizers, herbicides & pesticides, labor & training, capital).”

Ausubel noted that Ohalo has left certain questions unanswered. “How much of the outcomes reported owes to polyploidy and how much to the hybrid genotype is unclear” (here, Ausubel is referencing the phenomenon of “hybrid vigor”). He also wonders about the nature of the intellectual property protection. “To what extent will Ohalo sell seeds, and to what extent will it sell information?” Finally, he warned that the usual resistance from anti-GMO activists may hinder Ohalo’s plans.

Overall, however, Ausubel is optimistic. “Ohalo’s success demonstrates the imminent chances for growers of diverse plants to peak in their use of farmland and to spare much more land for nature.”


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