Generating HLB-Resistant Citrus Using Gene Editing
At UF/IFAS, we are working on finding solutions for Florida’s citrus growers. This is a summary of one project made possible by state legislative funding for the UF/IFAS Citrus Initiative during the 2018-19 funding cycle. It documents how we are making progress and providing Florida growers with reasonable, pragmatic solutions to successfully grow citrus in this new age of citrus greening.
Researcher: Nian Wang, Microbiology and Cell Science
IMPACT: Significant progress has been made in the identification of genes that make the citrus plant susceptible to HLB as well as genes that make citrus resistant to HLB, moving closer to generating a citrus greening-resistant plant. Progress has also has been made to optimizing the gene editing CRISPR technology and generation of HLB-resistant citrus using biotechnology. Multiple plants have been generated and are being tested for HLB resistance. There is also greater understanding of the biology of the bacteria that causes HLB. All these results will help the industry with short and long-term solutions to control HLB.
The goal of multiple research initiatives led by Nian Wang of the UF/IFAS Citrus Research and Education Center is to generate HLB-resistant citrus via biotechnological approaches such as gene-editing with the CRISPR technology. In the process, researchers have confirmed the HLB-susceptibility genes in the citrus genome. Identifying the HLB-susceptibility gene will lead to understanding how to “turn off” that gene through biotechnological approaches. This in turn leads to generating a non-transgenic, HLB-resistant citrus plant. In a companion study done by Wang, canker-resistant citrus plants have been generated by turning off a susceptibility gene showing the potential of this approach.
Multiple genome-modified plants have been generated and are being tested for HLB resistance. In the process, the efficacy of genome editing has been increased. Some genome-modified citrus plants generated with additional biotechnological approaches have showed lower bacterium levels or no infection compared to control plants.
Researchers have also made significant progress in understanding the biology of the bacterium. This information is helpful in designing new control strategies. These strategies include knowing the most efficient methods needed to control the bacterium and being able to detect the bacterium before symptom appearance in trees. All these findings will help the industry with some short-term solutions.