use of x rays ultraviolet radiation or nitrogen mustards can also be cultivated to produce obafluorin isolation of pseudomonas fluorescens from a plant specimen obtained in princeton n j on which it is present can be accomplished by cutting the plant leaves stems and flowers into small pieces under aseptic conditions the plant pieces 2 g are suspended in 100 ml of sterile diluent nacl 8 5 g kh 2 po 4 0 3 g na 2 hpo 4 0 6 g gelatin 0 1 g distilled water to 1 liter and the suspension is shaken well the aqueous layer is serially diluted using conventional techniques plated and incubated at 37 u00b0 c for 1 2 days on mcconkey 39 s soil extract agar which has the following composition ______________________________________mcconkey 39 s agar 15 0 gsoil extract 200 0 mldistilled water 800 0 mlsterile 0 1 biotin solution 1 0 mlsterile 0 2 thiamine solution 1 0 mlsterile 1 0 actidione solution 10 0 ml______________________________________ added aseptically to the already sterile mcconkeysoil extract agar medium pseudomonas fluorescens a t c c no 39502 is a gram negative rod occurring singly or as short plump diplobacilli motility is achieved by means of 1 or more polar flagella the organism is oxidative both on triple sugar iron agar and hugh leifson 39 s o f glucose test it is cytochrome oxidase positive and.