Association of Tobacco ringspot virus, Tomato ringspot virus and Xiphinema americanum with a decline of highbush blueberry in New York

Plantings of highbush blueberry cultivars ‘Patriot’ and ‘Bluecrop’ showing virus-like symptoms and decline in vigor in New York were surveyed for the occurrence of viruses. Tobacco ringspot virus (TRSV) and Tomato ringspot virus (ToRSV) from the genus Nepovirus in the family Comoviridae were identified in leaf samples by DAS-ELISA. Their presence was confirmed by RT-PCR with amplification of 320-bp and 585-bp fragments of the RNA-dependent RNA polymerase genes, respectively. Comparative sequence analysis of viral amplicons of New York isolates indicated moderate (80.7-99.7 %) to high (90.8-99.7 %) nucleotide sequence identities with other ToRSV and TRSV strains, respectively. Soil samples from the root zone of blueberry bushes contained dagger nematodes and cucumber bait plants potted in soil samples with identified X. americanum became infected with ToRSV or TRSV. Altogether, ToRSV, TRSV, and their vector X. americanum sensu lato are associated with the decline of highbush blueberry in New York.