Citrus greening disease (Huanglongbing or HLB) is a devastating disease that has caused severe losses to the citrus industry worldwide. Caused by the bacterium Candidatus Liberibacter asiaticus (Las), HLB is spread by psyllids and affects the vascular system of citrus trees, leading to yellowing of leaves, stunted growth, and eventually death. Currently, there is no cure for HLB, and management strategies primarily focus on controlling the psyllid vector.

In a recent study published in the journal Nature Plants, researchers from the University of California, Riverside, have developed a novel approach to protect citrus trees from HLB using plantibodies. Plantibodies are plant-produced antibodies that can recognize and bind to specific targets. In this case, the researchers engineered citrus trees to produce plantibodies that specifically target the Las bacterium.

The researchers used a technique called agroinfiltration to introduce the plantibody genes into citrus plants. Agroinfiltration involves using a modified strain of the soil bacterium Agrobacterium tumefaciens to deliver genetic material into plant cells. Once inside the plant cells, the plantibody genes are expressed, and the plantibodies are produced.

The results of the study showed that the plantibodies were successfully produced in citrus plants and were able to bind to Las bacteria. Furthermore, the researchers found that the presence of plantibodies in citrus plants reduced the accumulation of Las bacteria and delayed the development of HLB symptoms.

This study demonstrates the potential of using plantibodies as a novel strategy to protect citrus trees from HLB. The researchers suggest that further research is needed to optimize the expression of plantibodies in citrus plants and to evaluate their efficacy in field conditions. If successful, this approach could provide a new and sustainable tool for managing HLB and protecting the citrus industry.