Occurrence, Identification and Preliminary Biological Control of Bulb Rot of Onion (Allium cepa)

Onion bulb rot was observed in low-temperature warehouses Mae Wang District, Chiang Mai, Thailand 2022. The pathogens were isolated and identifi ed as Pantoea agglomerans Burkholderia gladioli based on morphological biochemical characterization, pathogenicity tests, 16S rRNA gene sequences. Biological control is regarded a safer more sustainable strategy than chemical has elicited great attention for disease control. Bacillus sp. isolate BB22 from rhizosphere soil evaluated its preliminary potential to inhibit the growth of onion bacterial by dual culture technique. results showed inhibition zones P. 30.1 mm B. 13.0 mm. Molecular cation performed using gyrA sequences confi rmed velezensis. PCR amplifi bmyB, fenD, ituA, srfAA genes coding bacillomycin, fengycin D, iturin A, surfactin, respectively, production these antibiotics. This study revealed application velezensis biocontrol agent against rot-causing onions.