Gooseberry vein banding associated virus on Ribes in Latvia: Occurrence, host plants and vectors

Ribes are essential berry crops in the temperate zones in Eurasia and New Zealand, and viral infections are common constraints in their cultivation. Gooseberry vein banding associated virus (GVBaV) is vectored by aphids and has been reported from a few European countries and North America. Knowledge on how GVBaV interacts with its vectors on Ribes is still limited. The occurrence of GVBaV in cultivated and wild Ribes in various habitats was studied, focusing on germplasm collections, wild localities, home gardens and green spaces where chemical plant protection is not applied. GVBaV was confirmed for the first time in Latvia in all studied Ribes groups except Ribes×nidigrolaria, and in all habitats surveyed; however, its occurrence did not exceed 8%. Ribes alpinum and R. aureum were found as new naturally infected hosts. GVBaV was detectable in single aphid specimens by PCR and confirmed in Aphis schneideri, Cryptomyzus galeopsidis, Cryptomyzus ribis, Hyperomyzus lactucae and Nasonovia ribisnigri. Phylogenetic analyses did not reveal supported clustering related to host or geographic origin, except for GVBaV isolates in A. schneideri obtained from cultivated gooseberry. This is the first study contributing to the understanding of virus genetic diversity in its vector species in relation to the host plants. A. schneideri that feeds only on Ribes is probably a major contributor to GVBaV spread in comparison with other aphid species migrating to secondary hosts.