A world without chiles is not a world worth living in. And they are at serious risk due to climate change.
In 1999, Susan Lin, a bespectacled plant researcher at the World Vegetable Center, in Taiwan, pulled on a pair of latex gloves and got to work cross-pollinating some chili peppers. She collected tiny white flowers from a cayenne-pepper plant, shook their pollen into a tiny test tube, and walked over to an aji-chili plant. Using tweezers, she removed the petals and anthers from its flower buds, exposing the thread-like stigmas that serve as the plant’s female reproductive organs. Then she dipped the stigmas into the pollen, hoping that they would eventually form peppers.
Lin was trying to breed a plant that was resistant to anthracnose, a fungal infection that blisters mature chili peppers with sunken patches that look like cigarette burns. The disease afflicts farms from New Jersey to New Delhi; in India alone, anthracnose was estimated to inflict losses of around four hundred and ninety-one million dollars a year, according to a 2014 paper. But the chilies never emerged. “There were so many flowers, but they never bore fruit,” Lin said. “It wasn’t successful.” In the years that followed, Lin tested more peppers from the W.V.C.’s refrigerated gene bank, which contains heirloom and wild seeds that have been collected from around the world. Finally, the team managed to breed a cayenne-esque pepper, derived from a habanero known as PBC932, that showed resistance to both anthracnose and another fungal infection, powdery mildew. The chilies looked misshapen—Lin called them “very ugly”—but they represented progress.
The world’s supply of fruits and vegetables is at risk. One recent study found that environmental shifts such as climate change, water scarcity, and biodiversity loss could reduce yields by a third by 2050; diseases like anthracnose, which likes hot and humid conditions, are expected to spread as average temperatures rise. Of the eleven hundred vegetable species that are recognized worldwide, about a quarter are in particular danger because they are not preserved in seed vaults. “We see that the diversity out there, in terms of fruit diversity and vegetable diversity, is declining,” Marco Wopereis, the director-general of the W.V.C., told me. “What is triggering that declining diversity is urbanization, industrialization, and the fact that people eat more of the same everywhere.”
The nonprofit World Vegetable Center, which sprawls across two hundred and ninety acres in the dusty suburbs of Tainan, exists to research and breed vegetables that are resilient to climate change, pests, and disease. It houses the largest public collection of vegetable germplasm, or genetic material, on the planet. Its library of Capsicum, the genus of plants that includes hot and sweet peppers, contains more seed samples than any other collection: some eight thousand, or roughly eleven per cent of the varieties held in gene banks around the world. Some of the W.V.C.’s seeds are more than twenty years old. Because germination rates decline over time, even in controlled conditions, Lin and her colleagues are constantly growing the seeds out, harvesting them, and putting them back into storage, to insure the vitality of each line.
It’s a constant battle to keep our crops functional due to what we have done to the planet. More than likely, we will lose many of these battles. But let’s at least win the chile battle.