While Arabica coffee around the world has been devastated by coffee rust, Robusta is doing just fine. Generally grown in southeast Asia, parts of Africa and Brazil, the variety can handle wide temperature and moisture changes, is naturally resistant to coffee rust, and is cheap to produce and easy to grow. It's generally used in instant coffee and flavored blends, where its acidic taste can be hidden.
Most coffee drinkers—at least those concerned with taste—don't like it.
"Robusta is much more tolerant of climate change, it has better heat tolerance, it's less dependent on orderly rainfall," Rhinehart says. "Unfortunately it doesn't taste as good in the cup."
That leaves few options for countries such as Colombia, which pride itself on its fine Arabicas.
Coffee is known as an "orphan crop," meaning that, internationally, little money is spent trying to understand how it is grown. There are countless organizations and companies dedicated to trying to grow better wheat, soybeans, corn and rice, an estimated $100 million annually is spent on learning how to grow a better coffee bean.
For decades, developing countries grew coffee and shipped it off to the developed world. The climate in coffee producing countries such as Costa Rica, Colombia, Ethiopia and Vietnam was relatively stable, and coffee hauls were generally predictable. That has changed recently as rust has spread and more variable temperatures have reduced coffee hauls.
"For most of the period we've been importing coffee, it's been grown in countries with emerging economies facing economic challenges," says Rhinehart, of the Specialty Coffee Association of America. "There was no significant coffee production in the industrialized north, so there was no investment from the consuming side into understanding coffee genetics and quality."
Most of those countries couldn't afford to put the resources into coffee research centers—with one notable exception: Colombia.
Since 1927, Colombia's Cenicafe research center, located in the country's main coffee hub of Manizales, has been one of the world's most important resources in combating diseases that plague coffee.
By crossing Arabica plants that seem more resistant to rust for several generations, a heartier plant can be grown. It's a process that can take decades: In 1982, Cenicafe released its first coffee rust-resistant bean, called the Colombia Variety. In 2005, it released a second generation plant, called Castillo, which is even more resistant to the fungus.
Corrected 03/28/13: An earlier version of this story misstated the total value of the worldwide coffee trade.