Written by Caroline Coatney
As I was drinking my morning cup of coffee the other day, I got an email from a friend about a Wired article describing the dire straits the coffee crop has found itself in and how transgenics could be a possible savior. Putting down my cup of joe, I started investigating what was going on with the coffee crop and what might happen to my future cups of coffee.
The Coffee Rust Problem
It seems coffee farmers are up against a large-scale affliction from the leaf-blighting fungus known as coffee rust (Hemileia vastatrix). Historically, coffee rust has been a recurring problem across the globe. It wreaked havoc in Sri Lanka, the Philippines, Java, and Malaya during the 1880s and 1890s and then spent the next hundred years making its way across the world and infecting nearly all coffee growing areas in the western hemisphere. General management practices have included building wind breaks (the spores of the fungus are wind and rain dispersed), spraying fungicides, and quarantining sick plants and killing all neighboring plants in the vicinity.
These practices seem to have worked more or less in the past, but they are inadequate against today’s current pandemic. Unfortunately, the coffee rust disease has two things going for it. The first is climate change. The fungus thrives in warm, humid air and, as the Wired article points out, temperatures in Central America are warming due to changing climate. Coffee farms at high altitudes that used to be protected from the fungus because of cool temperatures are now finding themselves infected just like their lowland neighbors as the coffee rust disease extends its range.
The second advantage coffee rust has is changing growing practices. Coffee is naturally a shade plant and, in the past, coffee farmers generally acknowledged this fact by planting the crop under the canopies of shady trees. However, in recent years, farmers have been reducing shady areas to increase plant density and yield. The increase in direct sunlight has lead to two unfortunate things: (1) field temperatures have risen and therefore have increased the ability of the fungus to germinate and spread, and (2) a shade-loving fungus that protects against coffee rust, known as white halo fungus, can no longer be a natural defense for the coffee plants.
Riding on the coat tails of climate change and ecologically imbalanced growing practices, the coffee rust fungus has put Central American coffee production on red alert. The fungus currently afflicts 50% of all growing areas in the region, stretching from Guatemala all the way down to Panama. Almost half a million people are out of work, production was down 15% from last year and is expected to be down 50% for the upcoming harvest in October, and Guatemala declared a state of agricultural emergency back in February.
The Transgenic Solution
So what is going to happen to coffee?
It seems, for now, that some coffee varieties will not be affected by the disease since they are naturally resistant. These varieties are the Robusta varieties, which are considered to be of lower quality than their Arabica counterparts. Arabica coffee varieties are used to make high quality brews and make up over 75% of the world’s coffee production (for more information on Robusta vs. Arabica, see this article from The Atlantic). However, they are not resistant to coffee rust.
So what is going to happen to the good coffee?
To save (Arabica) coffee, we need to act fast. Faster than the coffee rust fungus. The incredible loss in production in only one year, 15% to 50%, should be clear evidence for how fast and devastating the disease can be.
We could try to take away some of the advantages the fungus has. Unfortunately, we cannot stop climate change any time soon, but farmers could try to revert to more ecologically sound growing practices. But could these changes be implemented and the benefits reaped fast enough to curb the fungus? Probably not.
We could continue what we have done in the past—applying fungicide, building wind breaks, quarantining—but these methods were in place while coffee rust built up its momentum over the past few years. It seems they have done all they can do.
We need something new. We need Arabica coffee varieties that are naturally resistant to the fungus.
One way we could do this is through conventional breeding, meaning crossing plants and selecting for the desirable trait(s) over a series of generations. This is a fantastic idea since it would lessen and possibly eliminate fungicide applications. The Colombian research organization Cenicafé has actually already developed a rust-resistant coffee variety and made it available to coffee farmers, but it is not a pure Arabica variety. Developing a pure Arabica, rust-resistant variety and releasing it for commercial use could take up to a decade, which is too much time.
We need transgenics to save coffee.
Coffee producers might fear that their economically perilous situation will become more perilous if consumers refuse to buy GMO coffee. But, I think the story of the Rainbow Papaya is an excellent example of how transgenics can bring a failing crop back from the brink.
In the 1990s, Hawaiian papaya farmers were up against the ringspot virus (Potyviridae). They were losing horribly—production was reduced to 50% within in six years (sound familiar?)—until Dr. Dennis Gonsalves, a plant pathologist, genetically engineered a virus-resistant variety, the Rainbow Papaya, which saved the Hawaiian papaya crop (see this previous Biofortified post for more information). Some consider the Hawaiian papaya a GMO success story and an excellent example of GMOs being used for good. Now, when papaya farmers had to decide if they would adopt the GMO papaya, they feared they would lose business—mainly from Japan, historically a major consumer—because of the switch to GMOs. However, from the time Rainbow Papaya was initially adopted, it has become the primary variety grown, the Hawaiian papaya industry has been recovering, and Japan even started accepting the variety in December 2011.
The time is now for transgenic coffee. Even if it is only used as a temporary relief until better growing practices can be implemented or the fungus can be put under control, there is a clear need for GMO coffee.
I look forward to my future cups of GMO joe.
Written by Guest Expert
Caroline Coatney is a plant breeder with experience in science communication and science policy. She has a Masters degree in plant biology from the University of Georgia.