At CATIE, Leandro conducts experiments in a giant garden of more than 4,000 cacao trees. She and other scientists note which trees are the healthiest and which produce the best-tasting beans.
Scientists try to infect some of the healthy trees with diseases to see which are vulnerable. “Some trees are resistant to attack,” she says.
Scientists use these resistant trees to develop new and improved cacao varieties. They select trees to breed together. Then they test the new trees by growing them in different locations to make sure they resist local diseases.
For Leandro, time is of the essence. Frosty pod rot, black pod, and witches’ broom have killed more than one-third of cacao trees in Central and South America. But the diseases haven’t yet reached West Africa, where most of the world’s cacao is grown. If they do, the consequences could be dire.