P-007 - Soil-borne Burkholderia species are associated with onion bulb rot in Vidalia onions in Georgia

Bacterial species from the Burkholderia genus cause sour skin and slippery skin rot in onion, resulting in millions of dollars in crop losses worldwide. There are more than 60 known species of Burkholderia that are ubiquitous in nature and can colonize a diverse range of niches including water, soil, hospital equipment, plant rhizosphere, plant roots and stems, humans, and various other animal species. The Burkholderia cepacia complex (Bcc) consists of several species that are pathogenic on plants and animals including humans. Several new Burkholderia species have recently been added to the Bcc, however, little is known about the diversity of Bcc species that cause onion sour skin and slippery skin rot. In bacterial systematics the recA gene has been extensively used for the identification and classification of Bcc species due to sequence variation within the gene that enables the discrimination of the various Burkholderia species. The main objective of this study was to isolate and characterize onion associated Burkholderia species in soils of the Vidalia onion-growing zone in Georgia by selective culturing, Sanger and Amplicon sequencing with recA gene. Our preliminary results indicate that a variation in soil Burkholderia spp. populations exists in diverse location of the Vidalia onion zone. Multiple Burkholderia spp. including B. cepacia, B. cenocepacia, B. ambifaria and others were detected from the soil and may potentially be associated with onion bacterial bulb rot.