New viral sequences and endogenous viral elements (EVE) in world-wide populations of Trioza erytreae, the African citrus psyllid.

The citrus industry is threatened by a devastating bacterial disease known as Huanglongbing (HLB) or citrus greening. Current control measures largely rely on chemical suppression of insect vectors, primarily Diaphorina citri and Trioza erytreae. A promising alternative lies in the biotechnological use of viruses that specifically infect these vectors. Although much progress has been made in elucidating the virome of D. citri, there is no data on the viral population that Trioza erytreae can harbor and/or infect it. In this study, we analyzed the virome of T. erytreae from the Iberian Peninsula, Madeira, the Canary Islands, São Tomé and Principe, the Reunion Islands, and South Africa. We identified seven new insect-specific viruses (ISV) belonging to the families Narnaviridae, Totiviridae, Solemoviridae, Phenuiviridae, Flaviviridae, and Tombusviridae, the last three detected only in South African populations, four mycoviruses of the Ambiguiviridae, Botourmiaviridae, and Partitiviridae families, and three viruses known to infect citrus. Furthermore, comparison with the DNA sequence database has allowed us to identify the presence of 22 actively expressed endogenous viral elements (EVEs; virus-derived genetic material integrated into the genome of a nonviral host). Our findings provide new insights into the virome of this important insect vector and new perspectives to its potential for biocontrol strategies against HLB.