Association of phytopathogenic Pantoea dispersa inner boll rot of cotton (Gossypium hirsutum L.) in Maharashtra state, India

Abstract

During 2018–19, unusually higher incidences of inner cotton boll rot were reported in farmers’ fields from cotton growing tracts of Maharashtra. Extensive survey was conducted to investigate these instances of boll rot. An unusual emerging problem in cotton has been associated with reduced boll development and yield. Green bolls with and without any sign of damage were collected from farmers fields and dissected under aseptic conditions. Bacterial species belonging to members of Enterobacteriaceae family (facultative anaerobe) were predominately isolated from rot affected cotton bolls. Four bacterial strains isolated from four locations were identified on the basis of morphological, biochemical and molecular characterization. Pathogenicity of all the four isolates (CBR2-YTML, CBR1-JLGN, CBR2-BLDN and CBR5-JLGN) was proved by Koch’s postulates. To the best of our knowledge, this is the first report of occurrence and association of phytopathogenic bacteria Pantoea dispersa, a member of the Enterobacteriaceae family as a potential and principal pathogenic agent causing inner cotton (G. hirsutum L.) boll rots in Maharashtra state, India.