Selective mediun the medium that can prevent the certain bacterial growth while permitting others. e.g. SS agar(Salmonella Shigella agar) Differential medium Escherichia cofr Some special substrates and indicators are added into the media in order to produce a visual differentiation when several bacteria grow on the same kind of medium e.g. Kligler Iron Agar pH indicator: phenol red Slant: containing lactose Slant agar of Kligler Iron Agar Butt: semisolid 克氏双糖铁斜面 containing glucose and Ferrous ammonium sulfate14 the medium that can prevent the certain bacterial growth while permitting others. e.g. SS agar (Salmonella Shigella Agar) Some special substrates and indicators are added into the media in order to produce a visual differentiation when several bacteria grow on the same kind of medium. e.g. Kligler Iron Agar • • Selective Medium Differential Medium Butt: semisolid, containing glucose and Ferrous ammonium sulfate Slant: containing lactose pH indicator: phenol red Slant agar of Kligler Iron Agar 克氏双糖铁斜面