The National Academies of Sciences, Engineering and Medicine has concluded that discovery a single solution for huanglongbing (HLB) remains unlikely.
That determination came as little surprise in Florida, where growers have been battling HLB for more than a decade. The long-term fix is probably genetically resistant trees, but in the meantime companies have been engaged in developing multi-faceted programs in hopes of mitigating the effects of HLB.
Stephen Futch, a citrus extension agent for the University of Florida, gave several examples.
“Any of those things that you can do to minimize the stresses to the tree, either moisture stress, nutrient deficiency, those kind of things tend to help the tree be able to survive with the disease a little bit better,” Futch said. “People are doing more frequent irrigation of smaller quantities, again a way to minimize moisture stress to the tree.”
That irrigation option doesn’t require more water, just adjusting by watering for a short time each day instead of every three or four days for longer durations, he said.
Growers have applied the same logic to nutrition, delivering it through irrigation systems and via other methods so the trees have a steady supply.
Most growers have adopted new strategies as well as new products like bacteriacides to fight the disease, Futch said.
With those efforts underway, many companies had hoped to have significantly more fruit for the 2017-18 season — until Hurricane Irma hit the state.
In California, commercial production has not yet been affected by huanglongbing, and the state has been aggressive in its work to maintain that status.
“It’s a challenge,” said California Citrus Mutual president Joel Nelsen. “There’s no question about it. We continue to get darn near daily reports, unfortunately, about backyard trees being discovered with HLB. We’re close to 600 trees being removed in Los Angeles/Orange County area.”
Homeowners have been cooperative in removing trees that are found to have the disease, but the overall program has been expensive and extensive.
The National Academies of Sciences, Engineering and Medicine put together the 170-page report at the behest of the Citrus Research and Development Foundation, according to a news release. According to the report, significant steps in the fight against HLB would include culturing the bacteria in a lab; developing advanced diagnostics for early disease detection; and creating standardized research methodology so the results of various studies could be easily compared.