Chocolate starts as cacao, a tropical tree that gets sick easily and takes years to breed. For the farmers who grow it, the long problem is not an empty store shelf. It is a harvest they may not keep. On October 27, Penn State said it had licensed a new cacao plant to a company, AgroNetica, to move the work closer to growers.
The change itself is tiny. Cacao's genome has about 450 million DNA bases. In one line, researchers led by plant scientist Mark Guiltinan changed two of them.
Those two letters sit in a gene called TcNPR3, which works like a brake on the tree's own defenses. The team used gene editing, then ordinary breeding to strip out the laboratory tools, leaving only the small change in the cacao gene.
Black pod disease, caused by a mold-like pathogen, is estimated to cut about 30% of cacao yields worldwide. It can also kill trees. Traditional breeding is slow. The plants need about three years even to make seed, and a new variety can take decades.
In the lab, leaves from the edited plants developed about 42% less disease than unedited ones. That number came from a leaf, not a farm. Field tests are already under way in Hawaii and Puerto Rico. The license is meant to take the trees further: if they hold up under real growing conditions, the company can grow more of them for farmers.