Spinach doesn’t just work for Popeye anymore… and no one knows that better than Dr. Erik Mirkov, a plant pathologist at the Texas A&M AgriLife Research and Extension Center at Weslaco, and professor in the department of plant pathology and microbiology at Texas A&M.
Citrus growers worldwide have been searching desperately for a cure to a devastating, citrus greening disease, or Huanglongbing, often referred to as HLB.
“Citrus greening is a citrus grower’s worst nightmare,” said Mirkov. “Because at this point, there is no cure. It can spread for years before it can be detected, so it’s insidious, to say the least.”
According to an article in the New York Times, the major orange juice brands have been rumored to be looking elsewhere — perhaps to Brazil, where growers have taken to abandoning infected groves to plant in new fields. And the industry’s tripling of pesticide applications to kill the bacteria-carrying psyllid has been, while within legal limits, becoming expensive and worrisome.
Dr. Mirkov knew that spinach produces a protein that attacks invading bacteria — a food, he reminded us, that “we give to babies.” He then transferred two genes from spinach into citrus trees, and in field testing, the transgenic trees have proven fruitful — pun intended.
Southern Gardens Citrus, a large citrus and juice producer in southern Florida, planted 300 juvenile trees with spinach genes alongside trees with no new gene. Row after row of trees with no spinach gene were sick with greening, according to the article. The 300 transgenic trees with Dr. Mirkov’s spinach genes were all healthy.
The next step will be to go through the lengthy and costly deregulation process that declares the fruit safe to eat.
“It could take three to four years to complete,” he said. “But it’s important to determine that the fruit produced from transgenic trees are safe to eat, especially by what are considered at-risk groups, which include infants, the elderly and those with compromised immune systems.”
That’s also the reason Mirkov works only with genes and proteins found in foods.
“I decided seven years ago when this program started that if the proteins were not commonly eaten, we wouldn’t work with them.”
Ray Prewett, president of Texas Citrus Mutual, a commodity group in Mission, said Mirkov’s work is important and promising.
“The majority of the support for Dr. Mirkov’s research has come from Florida, but the Texas citrus industry has provided some financial support as well,” he said. “The entire U.S. citrus industry is placing a lot of hope and faith on the outcome of this research. Our industry is using all of the currently available tools to fight the disease recently found in Texas, but we are counting on disease-resistant trees as our best long-term solution.”
Citrus greening is thought to have originated in China in the early 1900s, according to the USDA website. It is primarily spread by two species of psyllid insects. Greening was detected in Florida in 2005 and earlier this year in the Lower Rio Grande Valley of Texas. It is not harmful to humans, but has harmed trees in Asia, Africa, the Arabian Peninsula and Brazil. [via AgriLife Today]
Read more about Dr. Mirkov’s research and the plight of the citrus industry in the New York Time’s Article: A Race to Save the Orange by Altering Its DNA.