Combining Multiple Methods to Manage HLB

Tacy CalliesGrapefruit, HLB Management, Research

HLB
Individual protective covers are used to protect trees from HLB in a Jackson grapefruit trial at the Citrus Research and Education Center.

At the recent Citrus Research and Education Center (CREC) field day and open house, Arnold Schumann showed visitors a Jackson grapefruit trial aimed at protecting trees from HLB. Schumann is a professor at the University of Florida Institute of Food and Agricultural Sciences CREC in Lake Alfred.

The trial combines the use of individual protective covers (also known as IPCs or mesh bags) with HLB tolerance. The IPCs are placed around the tree to protect them against the Asian citrus psyllid, the vector of HLB disease. The coverings enable the trees to get a growth spurt and be able to fight off the psyllid more effectively after they are removed.

Schumann says the IPCs get trees into a productive size before they are impacted by HLB, which slows down tree growth. “Even the tolerant trees get slowed down,” he said. “We’re keeping them completely free of that inhibition for up to two years, so they get a head start … We’re combining a lot of the factors like tolerance of the scion to HLB, tolerance of the rootstock to HLB and protection with bags. We’re enhancing growth by having high-density aquaponics fertigation. We’re putting a lot of factors together to increase the likelihood of being profitable and not succumbing to HLB.”

Once the bags are removed, the trees are ready to bear fruit. This system allows for a quicker and more efficient productivity of the trees. Instead of waiting three to four years for the trees to bear fruit, trees in this trial are producing fruit in one to two years.

“In my experience, when you grow trees like this with hydroponics, in the second year they bear fruit. It’s quite amazing,” Schumann said. “The sooner you can pay back your loans and things, the better. Early money is great.”

The research also includes a more densely populated grove of 871 trees per acre.

“The cost of the extra trees will be more than offset by the early yield and high profitability,” said Schumann.

He noted that trees with IPCs are still vulnerable to other pests and diseases, but the coverings allow for appropriate chemical applications to be made.

Share this Post

About the Author

Clint Thompson