By the time orange grower Gabriel Simoes noticed symptoms of the incurable “greening” disease last year, it was too late to do anything about it. Now four of every five trees in his 1,000-acre orchard are dead or dying.
Industry officials say it’s only a matter of time before California’s $1.2-billion citrus industry is threatened by the “mother of all citrus diseases,” which has invaded thousands of acres here in Brazil’s citrus belt with sickening speed.
“For a family business like ours that truly loves oranges and grew along with citrus culture in Brazil, it’s been very tragic,” said Simoes, 26, who studied business at the University of Oklahoma. “But there are forces greater than us.”
Coming on top of climate change and a depressed commodities market, greening has become a nightmare for the world’s largest citrus industry in the four years since it was first detected here in Sao Paulo state.
Twenty-five percent or more of the state’s groves could disappear in coming years if a cure isn’t found, according to Markestrat, a market research firm in Ribeirao Preto, the center of the state’s citrus industry. Others say the toll could be far worse.
“Greening isn’t just any disease,” said Nelson Marega Barrancos, manager of one of Brazil’s largest orange groves, a 4-million-tree plantation. “There is no way to stop it. The future is not good.”
Although greening has not yet struck California, carrier insects called psyllids were caught in traps in San Diego and Imperial counties in August, apparently after having crossed from Mexico. Authorities have since declared a 1,000-square-mile quarantine in parts of those two counties, restricting plant traffic.
“This is the mother of all citrus diseases. . . . I see no reason for the disease not to be here eventually,” said MaryLou Polek, a plant pathologist with the industry-financed Citrus Research Board in Visalia.
The plague has already gained a foothold in the U.S. Since greening was spotted in Florida in 2005, a year after its arrival in Brazil, it has spread throughout the southeastern United States and Texas. Before that, the disease wiped out entire citrus industries in China, India, Saudi Arabia and Egypt before migrating west.
Beth Grafton-Cardwell, an entomologist and citrus expert at UC Riverside, said the state’s orange grove owners and even homeowners with a tree in the backyard have reason to fear for their fruit.
“This is the scariest thing that’s happened to the citrus industry in a long, long time,” Grafton-Cardwell said.
Also known as huanglongbing after its Chinese origins, citrus greening is transmitted by aphid-like bugs the size of rice grains. Sucking fluid out of tree leaves, they leave a bacteria that paralyze a tree’s vascular system, cutting the flow of sugar and carbohydrates from leaves to the roots.
The result is a tree too weak to grow healthy fruit. Oranges shrink and take on a highly acidic taste.
One insidious feature is its latent impact. By the time farmers such as Simoes notice the fading leaf color, the telltale effect of the disease, the plague has usually spread to most of the orchard.
Scientists are far from understanding even the disease’s pathogens, or destructive agents, much less possible cures. That means orange grove owners’ only means of combating the plague is to destroy diseased trees and fumigate against the psyllids in hopes the disease hasn’t spread. With uncultivated land still plentiful in Brazil, growers have been able to plant new trees far away from greening “epicenters,” often in other states.
That sort of a geographic flight was still an option to California growers after World War II, when a disease called tristeza devastated the state citrus industry then concentrated in Orange County and the Los Angeles basin. To escape the plague, most growers replanted in the Central Valley, Polek said.
But that evasive tactic is no longer viable for “landlocked” California growers. Nor will the eradicate-and-spray model work for long. “It’s an unsustainable model, because you’ll end up pulling up all the trees,” said Mark Brown, a University of Florida agricultural economist.
As part of an emergency response funded by California growers and the U.S. government, Polek will open a diagnostic lab in San Diego next month to test for infected trees and psyllids. Her staff will be able to use equipment already in place to test for avian flu and West Nile virus, she said.
With help from the federal government, scientists in California and Florida are gearing up research projects to develop a cure, but at this point are far from finding one, said UC Riverside’s Grafton-Cardwell.
“The outlook is not encouraging,” she said, adding that the cure may lie in a transgenic strain of orange tree, an unappetizing prospect for some consumers who don’t want genetically engineered produce.
The Florida citrus industry, which fears it will be wiped out if a cure isn’t found, tripled its greening research budget this year to $20 million and issued a plea to scientists, offering to fund research projects. This month, regulators, scientists and growers from 26 countries attended a conference in Orlando that was called to help raise consciousness of the threat, Polek said.
The spread of the disease comes at a bad time for Florida’s orange growers, crippled by three devastating hurricanes in 2004 and 2005 and a 25% decline in U.S. orange juice consumption since 1999 resulting from shifting consumer tastes, Brown said.
He said that the annual rate of citrus tree loss from disease and age has doubled, to 5%, since 2004, and he suspects greening is the chief cause.
Sunshine State growers are also under increasing pressure from Brazil’s highly efficient industry, which is dominated by a handful of orange-juice-processing firms that now ship frozen and not-from-concentrate juice around the world.
(California growers are under less pressure because nearly all of their oranges are sold as table fruit, with only cast-offs used to make juice. Brazil doesn’t export fresh oranges.)
“Invented” in the 1960s by Florida growers who came here to plant supplemental crops after a series of devastating freezes in their state, Brazil’s OJ industry has grown to become the world leader, said Thomas Spreen, an agricultural economist at the University of Florida.
In any given year, Brazil now supplies up to a third of the juice U.S. consumers buy and 80% of global exports overall.
But greening has been a huge setback. For Simoes, the disease strikes as his family, which has raised oranges since 1966, struggles with other problems.
Commodity prices of orange juice have fallen to a four-year low, while costs such as fertilizer have skyrocketed. If that weren’t enough, climate change has meant less rainfall and higher irrigation costs.
Simoes says his family is considering a move to sugar cane crops to tap into the expanding ethanol market. But it would mean increased mechanization and negative social consequences, because sugar is less labor-intensive. He says he already has had to lay off four workers and more jobs would be jeopardized with a crop switch.
It would also mean leaving behind a way of life he loves: “This disease will make it ever so difficult to pass citrus farming down to future generations of our family.”