Abstract
The recently described member of the genus Trichovirus grapevine Pinot gris virus (GPGV) has now been detected in most grape-growing countries. While it has been associated with severe mottling and deformation symptoms under some circumstances, it has generally been detected in asymptomatic infections. The cause(s) underlying this variable association with symptoms remain(s) subject to speculations. GPGV genetic diversity has been studied using short genomic regions amplified by RT-PCR but not so far at the pan-genomic level. In an attempt to gain insight into GPGV diversity and evolutionary history, a systematic datamining effort was performed on our own high-throughput sequencing (HTS) data as well as on publicly available sequence read archive files. One hundred new complete or near complete GPGV genomic sequences were thus obtained, together with 69 new complete genomes for the other grapevine-infecting Trichovirus, grapevine berry inner necrosis virus (GINV). Phylogenetic and diversity analyses revealed that both viruses likely have their origin in Asia and that China is the most probable country of origin of GPGV. However, despite their common taxonomy, origin, and host, these two trichoviruses display very distinct genetic features and evolutionary traits. GINV shows an important overall genetic diversity, and is likely evolving under a balancing selection in a very restricted region of the world. On the contrary, GPGV shows a worldwide distribution with a modest genetic diversity and presents a strong selective sweep pattern. Taken together, these results show how two closely related trichoviruses differ drastically in their evolutionary history and epidemiological success. Possible causes for these differences are discussed.