Study flagellum and fliC of the causative bacterial agent of saffron corm rot disease Burkholderia gladioli pv. gladioli, a strategy in identification and prevention of disease spread

Burkholderia gladioli pv. gladioli (Bgg) is the causative agent of saffron bacterial rot. Accurate identification methods will play an important role in disease control management. Flagellum is the main commodity of the bacteria that facilitates its movement. Furthermore, it is of particular importance in colonization and pathogenicity. The fliC gene is one among five other genes encoding flagellin, the protein that makes the flagella in bacteria. In this study, the flagellin genes of 11 bacterial species were selected and the phylogenetic tree analysis divided them into plant and animal bacteria groups. Electron microscope images were taken from the bacterial flagella and its length was up to nine microns with 400-600 nm in diameter; as observed in both Lophotrichous and Monotrichous forms. fliC was amplified and analyzed for the first time by polymerase chain reaction for the two isolates of bacterial pathogen of saffron. Specific primers were designed and used that managed to separate Bgg from other bacteria, and helped in distinguishing the infected saffron corms from the healthy. Electron microscopy of the flagellum was illustrative of different types of Bgg. Investigating and studying the fliC gene can be useful in diagnosis of the causative agent of saffron corm rot disease.