Bt to Help Combat Devastating Citrus Greening Disease

Scientists at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) are testing a new type of genetically edited citrus tree that can fight off Asian citrus psyllids, the insects responsible for citrus greening disease, also known as Huanglongbing (HLB). The modified tree was developed in the lab and greenhouse and will soon be tested in the field.

The scientists inserted a gene from the soil-borne bacterium Bacillus thuringiensis (Bt) into a citrus tree that produces a protein that can kill baby Asian citrus psyllids. The gene yields a protein in the phloem, the vascular part of a leaf where the psyllid feeds. The UF/IFAS research team found that the protein derived from Bt can kill the vast majority of the psyllids in their earliest stages. No new adults can emerge on the tree, so adults laying eggs on these plants will not perpetuate the population.

Since 2005, HLB has damaged most of the citrus trees in Florida, including the fruit they bear, leaving growers and scientists seeking answers to the disease. “Given the widespread use of Bt proteins for protection of other crops against insect pests, we think we're on the right track for control of the Asian citrus psyllid,” said Bryony Bonning, an eminent scholar and entomology professor on the main UF campus in Gainesville, who led the research to identify the bacterial proteins that kill psyllids.

Read more details in University of Florida News.