HLB Management Requires an Integrated Approach

At the recent Citrus & Specialty Crop Expo, Ozgur Batuman reminded seminar attendees there is no silver bullet for HLB management. Instead, the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researcher proposes that growers integrate several tools for the management of HLB.

These tools include a variety of ways to control HLB-spreading psyllids; oxytetracycline (OTC) trunk injection; and plant defense inducers (PDIs).

PSYLLID CONTROL

Batuman, associate professor at the UF/IFAS Southwest Florida Research and Education Center, said individual protective covers (IPCs) are excellent tools for protecting young trees from psyllids and other pests and pathogens. Citrus under protective screen (CUPS) also excludes psyllids from trees.

Combining IPCs and brassinosteroids can prolong health and improve fruit yield and quality in newly planted trees, the researcher reported. IPCs, which can be used in new plantings and resets, are costly and laborious and can be used for two to three years depending on the cultivar, he added.

Other psyllid control measures that Batuman recommended are chemical and biological control, reflective mulch and kaolin spray.

OTC

“Oxytetracycline is the current hope for growers and is effective,” Batuman stated.

He cautioned that the rate of degradation of OTC increases under intense UV radiation and high temperatures — conditions inherent to Florida citrus groves.

“Our research has demonstrated that both OTC quantity and bacterial inhibition decrease with increased exposure to field conditions,” Batuman added.

PDIs

PDIs can protect young shoots from reinfection by psyllids after IPC removal, Batuman reported. Some PDIs protected young shoots from getting infected by CLas (the bacterium that causes HLB) for up to 10 months, he said.

BATUMAN’S RESEARCH

Batuman stated that his UF/IFAS program develops practical tools for growers to use in HLB integrated pest management (IPM).

His program also collaborates with experts in academia and industry in:

• Screening for new therapeutics
• Adopting new tools (IPC and automated trunk injection systems)
• Using resistant interstocks
• Testing HLB-resistant citrus cultivars
• Developing RNAi and CRISPR strategies
• Developing transgenic strategies
• Characterizing insect-specific viruses
• Searching for effective new IPM tools

See Batuman’s full Expo presentation here.