Submitted to: Phytopathology
Publication Type: Research notes
Publication Acceptance Date: 2/20/2003
Publication Date: 4/20/2003
Citation: Phytopathology. 2003. 93 pg s43 Interpretive Summary: Abstract only
Technical Abstract: Although phytopathogens can be found in all orchid production areas, Hawaii grower knowledge about the diseases rarely extends beyond recognizing whether the pathogen is viral, fungal, or bacterial. We report the results of a survey that we conducted with local growers to determine the prevalence of bacterial orchid diseases in Hawaii. On various orchid genera, we recorded symptoms ranging from leaf spots with or without water-soaking or chlorosis to soft rots. Bacteria isolated and cultured from the advancing edges of the lesions were tentatively identified using API strips and standard physiological and biochemical tests. Identification was confirmed by bacteria species-specific PCR. We commonly identified Erwinia spp. and Burkholderia spp. from diseased orchid tissue. Testing these isolates for growth on media containing copper or streptomycin showed our isolates to be resistant. Our field survey and laboratory data suggest that Hawaii's growers may have inadvertently selected for resistant strains of phytopathogenic bacteria that are now persistent in their stock.