First Report of <i>Robbsia andropogonis</i> Causing Bacterial Blight of <i>Danae racemosa</i> (Poet's Laurel) in a Virginia Ornamental Nursery

Danae racemosa (L.) Moench (Asparagaceae, Monocots) is a shade-tolerant, evergreen shrub native to Persia. On 2 July 2024 in Hanover County, Virginia, 300 plants in 7.6-liter containers were observed with blotchy, rust-colored, water-soaked lesions on the cladophylls and stems. Heavy bacterial streaming was observed from the lesions under the microscope, and sterilized tissue was cultured on King's B medium at 22 ± 2°C. After 72 h, cream-colored colonies developed that were oxidase and gram negative and did not produce fluorescent pigments on King's B medium. PCR amplification and sequencing of the partial 16S rRNA, gyrB, and rpoD genes from strain GS24-DSB16 were deposited into the National Center for Biotechnology Information (NCBI) GenBank database (PQ181184, PQ182786, and PQ182787, respectively). Based on the morphological and molecular characteristics, the causal agent was identified as Robbsia andropogonis (Smith) Lopes-Santos et al. Koch's postulates were fulfilled by wounding 20 cladophylls from each plant with a sterile needle, and 10 μl of an aqueous bacterial suspension was pipetted onto each wound. R. andropogonis has a wide global distribution from a host range spanning &gt;15 plant families, including maize, sorghum, sugarcane, citrus, coffee, carnation, and bougainvillea. To the authors' knowledge, this is the first report of the bacteria causing blight on D. racemosa and the first host in Asparagaceae.