For related articles and more information please visit OCA’s Resource Center on Genetic Engineering and Biotechnology.

Editor’s Note: This article notes that cultivating resistant varieties is a possible option to fight this disease and also notes that genetic engineering to fight plant diseases has so far not been effective. So why would that be “the only answer” in this case? Oh, and Anita Bryant is also remembered not so fondly by many people as being homophobic.

For many Americans, few things seem more wholesome than a glass of fresh-squeezed Florida orange juice, the original “natural food.” As former beauty queen Anita Bryant chirped more than four decades ago, in what remains a fondly remembered tagline: “A day without orange juice is like a day without sunshine.”

She wasn’t talking about green oranges or genetically altered ones, but that was then.

We live in a “world of nasty bacteria now,” says Calvin Arnold, a scientist with the U.S. Department of Agriculture. An insect-borne bacterial disease that is ravaging Florida’s citrus crop means the juice squeezed from the Sunshine State’s fruit may soon come from trees that have had their genetic makeup modified.

The blight, commonly known as “greening,” is the world’s most destructive citrus disease.

GMO juice would likely be reviled by critics of the biotech industry as “Frankenfood.” But Arnold and other experts say there simply may be no other choice in the battle against greening.

“It’s the most serious disease threat that the Florida citrus industry has ever faced,” said Arnold, a 67-year-old official with the USDA’s Agricultural Research Service.

As the director of the U.S. Horticultural Research Laboratory in Fort Pierce, in the prime Indian River region of Florida’s citrus belt, Arnold is on the frontlines of what he and others describe as an all-out push by the biotech industry, and geneticists in particular, to develop an effective weapon against greening.

Most scientists who have studied the problem seem to agree that genetic modification, and the cultivation of trees resistant to the bacteria that causes “greening” disease, currently hold out the only real long-term hope of fighting it.

That was the conclusion of a report sponsored by the Florida Department of Citrus and U.S. National Academy of Sciences in March, which highlighted the need for urgency to save Florida’s $9 billion citrus industry.

There are significant risks of failure, though, even as more money is poured into research. Much of the U.S. funding has come from Florida growers themselves, who have earmarked $15 million for the fiscal year ending in June 2011 on 120 different projects aimed at coming up with a solution to greening.

For all their promise, since genetically modified crops made their commercial debut in the United States about 15 years ago, the biotech industry has so far had only limited success in using genetics to develop resistance to bacterial diseases.