Huanglongbing disease could be mitigated with antioxidants and gibberellin

Researchers have found evidence that Huanglongbing, also known as citrus greening, This is an immune-mediated disease, which can be mitigated with antioxidants and phytohormones such as gibberellin, lifting the veil on the mechanism that causes this disease. O article on this study was recently published in Nature Communications.

Huanglongbing disease, which affects citrus fruits and ornamental plants, is caused by the bacterium Candidatus liberibacter transmitted by the citrus psyllid, a biting-sucking insect vector that also causes considerable direct damage to plants. The African psyllid (Trioza erytreae), vector of the bacterium Candidatus liberibacter africanus, is listed as a quarantine pest in Europe and its presence in Portugal has been expanding. O citrus greening is considered the most serious disease for these plant species worldwide.

The team from the Citrus Research and Education Center at the University of Florida (USA) shows that the infection of orange trees (Citrus sinensis) by the bacterium Candidatus liberibacter asiaticus induces a chronic systemic immune response in the plant's phloem, mimicking chronic systemic inflammatory diseases in humans, which leads to the death of the cells that make up the phloem tissue.

The conclusion that this is an immune-mediated phytopathology “helps guide the battle against this infamous disease”, the authors state in the article. The researchers consider it likely that horticultural approaches that suppress the oxidative stress of infected plants could mitigate the damage, including the optimal use of plant growth hormones such as gibberellin and brassinosteroids, as well as treatments with antioxidants.