LABS RESEARCHING CROP TRANSFORMATION ACROSS UF
Faculty from seven academic units housed at the UF/IFAS main campus in Gainesville and the Citrus Research and Education Center (C-REC), Lake Alfred, FL contribute to CTC. We work closely with the Applied AI Agriculture Center at the Gulf Coast Research and Education Center and the Protein Knowledge Integration team to rapidly advance plant breeding. Several recently awarded project are featured here.
Focus: Cutting-edge precision genome-editing technology to help plant breeders develop more varieties that are tolerant and/or resistant to citrus greening disease. The central hypothesis for this research is that HLB can be controlled by mitigating reactive oxygen species (ROS). ROS, such as hydrogen peroxide, are chemicals that cause damage to citrus plants. Scientists plan to prevent ROS damage caused by HLB disease by increasing the levels of antioxidant enzymes in citrus plants, which in turn will reduce ROS damage.
Focus: Render HLB functionally irrelevant by developing an IPM system that yields economic return from citrus. The research will address three aspects of HLB: Suppress psyllids to the point where management decisions are based on vector density and seasonal biological events. This way, management costs do not exceed yield losses. Evaluate the viability of trunk injections as a therapy to reduce bacterial populations. Integrate the use of gibberellic acid to mitigate disease symptoms.
Focus: While tree-trunk injections reduce CLas, they do not specifically target the phloem, the part of the vascular system in a citrus tree through which HLB travels. Most of the injected antibiotic is introduced in the xylem, where there’s no bacteria. Thus, the antibiotics don’t efficiently reach the phloem. Amit Levy, an assistant professor of plant pathology at CREC, plans to lead a team that will add a glucose molecule to antimicrobial compounds. This should dramatically improve their delivery into the phloem and reduce the dose needed for efficient HLB control.
Focus: Scientists have found HLB resistance in the citrus-related species known as Eremocitrus glauca (Australian desert lime). But transferring the resistance into commercial varieties typically takes decades because citrus remains in its juvenile stage so long. UF|IFAS has found an Eremocitrus variety with early flowering. Scientists propose to breed varieties of commercial quality with HLB-resistance, by speeding up the breeding process using early flowering varieties.
Focus: Study scions with demonstrated HLB tolerance and the potential to produce commercial-grade fruit, despite testing positive for CLas. Researchers will examine plants infected in established groves and uninfected in facilities known as Citrus Under Protective Screens (CUPS). From there, they’ll make a comparative genetic and horticultural analysis of uninfected material vs. tolerant and susceptible-to-infection material. Ultimately, researchers want to distribute HLB-tolerant scions to stakeholders and to understand the biological mechanisms behind HLB tolerance for breeding HLB-tolerant and -resistant scions and for gene editing purposes.