Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/25/2002
Publication Date: 1/1/2003
Interpretive Summary: This is the first North American report of tomato spotted wilt virus (TSWV) infecting blackberry lily, a relatively new perennial garden flower. A description of foliar symptoms is included. Diagnostic methods used to confirm the identity of tomato spotted wilt virus are also described. This thrips-vectored virus causes serious economic losses in many plants in North America and throughout the world. This report continues a collaborative vegetable virology research effort between ARS, Florida Department of Agriculture and Consumer Services-Division of Plant Industry and University of Florida. It also provides a timely account of TSWV infection of blackberry lily to growers, Extension personnel and state and Federal regulatory and research scientists.
Technical Abstract: Blackberry lily [Belamcanda chinensis (L.) DC.] is an herbaceous perennial in the Iridaceae characterized by purple-spotted orange flowers followed by persistent clusters of black fruit. We observed virus-like symptoms including chlorotic ringspots and ring patterns on blackberry lily leaves in north Florida nursery stock in 1993 and in a south Florida ornamental demonstration garden in July 2002. Inclusion body morphology in the south Florida plants suggested the presence of a tospovirus. Tomato spotted wilt virus (TSWV) was specifically identified in both locations by serological testing using ELISA (Agdia, Elkhart, IN). Sequence analysis of a nucleocapsid (N) protein gene fragment amplified by RT-PCR with TSWV-specific primers from total RNA extracted from the south Florida plants confirmed the diagnosis. Nucleotide and deduced amino acid sequences of a 579 base pair region of the RT-PCR product were 95-99% and 95-100% identical, respectively, to TSWV N gene sequences in GenBank. Because they were grown on-site from seed, the south Florida plants were likely inoculated by thrips from a nearby vegetable research plot. To the best of our knowledge, this is the first report of TSWV infection of blackberry lily in North America although TSWV was observed in this plant in Japan twenty-five years ago.