The fight to save Florida’s orange trees has literally been taken to a higher level.
In case you didn’t know, the state’s $9-billion-a-year industry has been crippled by “citrus greening,” a incurable disease carried by a bug called the Asian citrus psyllid. The bacteria, also known as huanglongbing, causes oranges, lemons, grapefruit, etc. to remain green and useless for consumption or sale. The only way that growers can manage the blight is by removing the infected tree before it wipes out an entire grove.
For a state that supplies 80 percent of America’s orange juice, this little bug is causing a giant problem. Just about every grove in the Florida — as well as every other citrus-growing locale here and around the world — has been infected by this bacteria. We previously noted that the Sunshine State already lost 8,000 jobs and $4.5 billion in crop damage. It’s also why wholesale OJ prices have just about doubled since 2000.
But as it turns out, scientists from the U.S. Department of Agriculture’s Agricultural Research Service in Puerto Rico and Florida have found that these invasive pests might have a weak-spot: heights.
For the two-year study (recently published in the Journal of Economic Entomology), researchers analyzed the Asian citrus psyllid populations at 17 different sites in Puerto Rico, ranging from 10 to 880 meters above sea level. Their findings showed that as elevations increased, the number of insects dipped. Intriguingly, at 600 meters above sea level, the population dropped to zero.
“We found the psyllid at all sites below 600 meters but none above it. At 500, we had a high level of psyllids,” David Jenkins, USDA researcher and co-author of the study, tells the Washington Post. It’s unclear why the psyllids don’t thrive in extra-elevated areas, but it’s suggested that they don’t like the difference in air pressure, temperature, oxygen levels, ultraviolet light or perhaps the food supply found in high elevation is unsuitable to their diets.
So how can the citrus industry apply this to their own groves? Planting nurseries above 600 meters is one way, the authors of the study suggest. Also, as Jenkins tells the Post, “if atmospheric scientists can somehow duplicate conditions near the trees, the psyllid could be controlled.”
The new research has already sparked interest. “In fact some people in Florida have contacted us,” Jenkins adds. “They want to conduct studies with pressure, as far as pressurizing tree. They’ve got atmospheric scientists looking at that kind of stuff. We’re not the ones that have the ideas on how to use it, but somebody out there may have the idea to make this practical.”
With genetic engineering and even parasitic wasps being touted as possible remedies, growers are desperate to save their trees. With any luck, the solution to keeping orange juice on the table will be found on higher ground.