Death of the orange?

A story that has been growing to alarming dimensions in Florida orange country is breaking through to national media, as the Washington Post delivers the astonishing news that we might be only a decade away from the effective end of oranges and their juice at our breakfast table.  It’s because of a Chinese bacterial invasion known as “huanglongbing,” a presently incurable disease that spreads like cancer, thanks to an insect that acquires the bacteria by feeding on infected trees and spreads it to healthy trees it infests.  It’s basically the orange-tree version of mosquito-borne malaria.

The Post describes huanglongbing’s effects: “Roots become deformed.  Fruits drop from limbs prematurely and rot.  The trees slowly die.”  The affliction is known as “citrus greening” because of the unpleasant color of the fruit.  Fruit from infected trees is not poisonous to humans, but it looks and tastes wrong.  $80 million worth of research has yet to produce a cure.

The University of Florida Citrus Research and Education Center says 67 percent of Florida citrus trees currently display signs of the bacteria.  Florida provides about 80 percent of the nation’s orange juice.  Other citrus-growing regions in the U.S., and around the world, have also reported outbreaks of the disease.

There is still hope that further research will find a way to cleanse infected trees of the huanglongbing bacteria, so the citrus industry is deeply concerned rather than completely panicking, but things will get rough if there isn’t a breakthrough soon:

Even those who are optimistic about a scientific breakthrough say that if the infection continues unabated for another decade or so ??? admittedly a worse-case scenario ??? Florida???s $9 billion citrus industry could be destroyed.

???What???s at stake is orange juice on the breakfast table,??? said Michael Sparks, chief executive of Florida Citrus Mutual, a trade association. ???I don???t want to indicate that???s going to happen next year. With a 10-year decline, your supply will reduce.???

[…] Since the disease???s detection in Florida City and Homestead, 90,000 acres of citrus have been wiped out. The high cost of spraying to kill off some of the psyllids is pushing some growers to the financial brink. The average cost of producing an acre of oranges is $1,800, nearly double what it cost in 1995.

???It???s a huge amount of money,??? said Stephen H. Futch, a University of Florida extension agent. A 2012 analysis estimated the disease has cost growers $4.6 billion and resulted in the loss of about 8,000 jobs.

In the heyday of Florida citrus, around 1970, the number of acres with orange, grapefruit and specialty fruit orchards surpassed 900,000. Today, it???s only slightly more than 500,000 acres, according to an analysis by Futch.

The industry has been coping with the devastation of huanglongbing the same way producers have been hiding all food inflation from the American public: by gradually reducing the size of juice containers, rather than increasing the price.  In the case of orange products, the supply is on the verge of contracting enough to require price increases everyone will notice.  The Florida orange industry relies on contributions from a large number of small growers who are becoming understandably nervous about their financial future.

In an interesting twist to the story, genetic engineering might be the salvation of the orange industry:

???What???s at stake is orange juice on the breakfast table,??? said Michael Sparks, chief executive of Florida Citrus Mutual, a trade association. ???I don???t want to indicate that???s going to happen next year. With a 10-year decline, your supply will reduce.???

Researchers funded by the industry, the state and the U.S. Agriculture Department are exploring an option that could save the trees and their citrus, but also turn off consumers: engineering and planting genetically modified trees that are resistant to the bacteria carried by the psyllid.

???Would that be accepted by the public???? Sparks asked. ???You don???t have to do a focus group or another survey to know it is a public concern.???

That’s an interesting question, because environmentalists have been mounting a vigorous effort to turn the public away from genetically-modified foods.  The hot battlefront at the moment is engineered salmon, the first Genetically Modified Organism (GMO) approved by the government for public consumption.  Environmentalists have successfully intimidated several major retailers, including Target and Whole Foods, out of carrying the fish, which spares them the trouble of convincing consumers not to eat them, or doing battle with government regulatory agencies in court.

Is that tactic going to work if genetically modified fruit is the only way to save the orange industry?  Salmon fisheries are said to be stressed by high demand, but we’re talking about an extinction-level event for oranges, playing out over the next ten to twenty years.  It might also soon occur to environmentalists to start complaining about the high volume of pesticides citrus growers are deploying in their desperate battle against the insect that transmits huanglongbing.

The Gainesville Sun has a long and fascinating look at the way genetic engineers are also performing detective work on the Chinese bacteria’s DNA, and brings news of a welcome breakthrough:

University of Florida plant pathologist Dean Gabriel may have cracked the genetic code that may help find a way to slow down or even stop the citrus greening contagion that’s infected as much as 75 percent of the state’s citrus crop.

He and his colleagues helped sequence the DNA of the Candidatus liberibacter asiaticus believed to cause citrus greening, and more recently sequenced the DNA of a similar strain of the disease discovered in Brazil.

That second discovery greatly improved their chances of nailing down which part of the bacterium causes the disease in the citrus trees.

???You can compare the two genomes that cause citrus greening, the one from Florida and the one from Brazil,??? Gabriel said.

By comparing those two against other bacterial strains from other plants like potatoes, spinach and papayas, and playing a game of ???one-of-these-things-is-not-like-the-others,??? Gabriel and his pathologists hope to deduce and isolate the part of the bacterium that attacks citrus.

It’s painstaking work, given they have 3,000 genes to examine, but it seems like the only way to devise a cure faster than the minimum five years of work estimated to lie ahead before traditional testing methods might develop a cure.  One intriguing possibility involves activating a virus lurking in haunglongbing’s DNA, flipping a “kill switch” that would cause the virus to devour its host bacterium.  But isn’t that exactly the sort of bio-engineering that leads to doomsday fantasies and mobilizes the environmental lobby?

Incidentally, the Brazilians have been controlling huanglongbing by immediately destroying infected trees, but that technique won’t work in Florida – as the Gainesville Sun puts it, “Nobody has pockets deep enough to withstand the destruction of 75 percent of their crops.”  That price will grow no easier to pay when the alternative is 100 percent destruction.