“We were all really disappointed,” said Julie Sardos, a French scientist for Bioversity International, a global research institute.

Scientists around the world are rushing to find and develop new types of bananas, driven in part by a potential crisis in the supply of the Cavendish—the variety commonly found in supermarkets around the world.

Bananas are one of the world’s most popular fruits, including in the U.S., which imports $2.3 billion worth each year.

The Cavendish is under threat of extinction from a fungal disease that is spreading across the world, killing the plants that bear the fruit. Cavendish bananas are seedless, so their plants are genetic clones, making them vulnerable to disease.

The soil-borne fungus is estimated to have damaged more than 30% of Asia’s and Australia’s banana plantations, and has made its way to Africa and the Middle East.

If it reaches Latin America and the Caribbean, source of 85% of the world’s banana exports and the majority of American fruit, it could wipe billions of dollars from the export industry. The fungus affects some lesser-known varieties, too.

So scientists are roaming through rural areas and working in their labs in pursuit of possible alternatives—though it’s proving hard to find ones with consumer appeal.

There are more than 1,500 types of edible and wild bananas, but they often look and taste peculiar. Some are squat. Some are red. Others fan out in semicircles rather than neat clumps.

Many have seeds the size of peas. Some are mushy, have thin skins or ripen too quickly. Some are even self-peeling, hanging on plants with their flesh exposed.

“The consumer is very attached to the highly predictable and totally dependable Cavendish banana,” said Miguel Munoz, a scientist based in Costa Rica at Dole Food Co., which sells more than five billion pounds of the fruit globally each year. It is “almost perfect,” he lamented.