Microbiome Diversity in Psyllids, “Non-vector” compared to a “Vector” of Huanglongbing

Authors: Hunter, Wayne; Stuehler, Douglas; QURESHI, JAWWAD - University Of Florida; CANO, LILIANA - University Of Florida

Submitted to: Symposium Series
Publication Type: Research Technical Update
Publication Acceptance Date: 8/29/2021
Publication Date: N/A
Citation: N/A

Interpretive Summary: Endosymbiotic bacteria living inside of insects that transmit pathogens, like the Asian citrus psyllid vector, ACP, affect their ability to transmit the pathogen. The pathogenic bacteria, Liberibacter, that infects citrus trees results in the disease called, Huanglongbing, which threatens global citrus production. Therefore to identify these key interactions inside of the psyllid vector linked to pathogen transmission, we compared the sequenced microbiome from a 'non-vector psyllid', the wild lime psyllid, WLP, Leuronota fagarae, which feeds on a wild type tree, that is related to citrus, called 'Lime prickly-ash'. This tree and the wild lime psyllid, are reported to not host the pathogenic bacteria. Genetic analyses showed major differences in the species of endosymbiotic bacteria living in the 'non-vector' psyllid. Since three endosymbiotic bacteria are needed in the ACP vector to transmit Liberibacter, and only one of these occurs in the 'non-vector' psyllid this may be the key to blocking psyllid transmission. Experiments are targeting these bacteria to turn the ACP vector into a 'non-vector' of Liberibacter, to stop the spread and reduce Huanglongbing of citrus trees.

Technical Abstract: Three endosymbiotic bacteria in the Asian citrus psyllid, Diaphorina citri, (Carsonella ruddii, Profftella armatura, and Wolbachia-Dc) are reported to strongly influence transmission of Liberibacter asiaticus, the bacterial pathogen that infects citrus trees resulting in the disease called Huanglongbing. This disease threatens global citrus production. Therefore we compared the microbiomes of the vector psyllid to a non-vector psyllid, the wild lime psyllid, Leuronota fagarae, which feeds on a related wild type citrus tree, called 'Lime prickly-ash', [Zanthoxylum fagara, L., (Sarg.)] (Sapindales: Rutaceae). Genetic analyses showed there are major differences in the endosymbionts in Leuronota fagarae, which only had one similar endosymbiont specie, Carsonella ruddii, in common. The differences in endosymbionts, provide new insight into their role and interactions affecting pathogen transmission. Thus they provide key interdiction points to blocking psyllid transmission. Therefore, experiments are targeting these bacteria to turn the psyllid vector into a 'non-vector' of the Liberibacter pathogen, to stop the spread and reduce Huanglongbing of citrus trees.