– It might not be obvious at the supermarket, but the banana industry is fighting to protect the most popular variety of the fruit from a destructive fungus.

A disease that ravages banana crops has made its long-dreaded arrival in Latin America, the biggest exporter of the crop. That's reigniting worries about the global market's dependence on a single type of banana, the Cavendish, which is known for its durability in shipping.

For years, scientists have said big banana companies like Chiquita and Dole would eventually need to find new banana varieties as the disease spread in countries in Asia and elsewhere. Then this month, the fungus was confirmed in Colombia, one of the top exporters in Latin America, prompting officials in the country to declare a state of emergency.

Banana-industry watchers said it's more proof the Cavendish's days are numbered, but that there's still plenty of time to find alternatives.

"I don't think it's going to impact the availability of the Cavendish in supermarkets anytime soon," said Randy Ploetz, a retired scientist from the University of Florida who studied tropical plant diseases.

While all sorts of bananas are grown around the world for domestic consumption, the ones shipped to places including the United States and the European Union are mostly Cavendishes. It may seem odd that the world banana market would hitch its fortunes to a single variety, but mass producing just one kind is a way to keep costs down, which also helps make bananas so widely available.

Bananas are also hard to breed, and finding varieties suited to global commerce isn't easy. In addition to being productive, Cavendish plants yield bananas that can survive the trip from warm climates to far-flung supermarkets, without ripening too quickly.

Not that long ago, the world market was ruled by another banana, the Gros Michel, aka the Big Mike. Experts said it was even easier to ship than the Cavendish, and sweeter (though others contend it tasted similar). Either way, the Gros Michel was ravaged by the 1950s by an earlier strain of the disease now stalking the Cavendish.

In Asian countries hit by the Tropical Race 4 disease, coping strategies have included planting less susceptible Cavendish varieties or moving to uninfected farmland, according to Ploetz.

So far, the fungus has been detected on six farms in Colombia. All are located in La Guajira, a province near the border with Venezuela. Officials said the affected area is still small at 490 acres, and is not making a dent on the country's exports. But there are concerns that the arrival of the disease will change Colombia's banana industry forever, forcing farms and the government to spend more on sanitary measures.

In La Guajira, officials have uprooted plants where the fungus has been detected and covered the soil with black plastic sheets that raise the temperatures to levels that could stop the disease from spreading. Healthy plants within a 60 foot radius of the affected areas are also killed with chemicals as a preventive measure.

"We will continue to work towards stopping this disease from spreading to the rest of Colombia," Agriculture Minister Andres Valencia told the Associated Press during a visit to La Guajira. "But eventually we have to make the transition to other varieties of banana that will resist this disease."