Toxicities of seven fractions isolated from clarified culture of P. fluorescens GcM5-1A to suspension cells of P. thunbergii 36 hr after treatment. a 10 μg aliquot of concentrated fractions III, IV, VI, VIII, IX, X and XII was added to 0.5 ml suspension cells, respectively. The cells were incubated at 28°C for 36 hr, and lethal rates were calculated under a fluorescence microscope after cells were stained with FDA (fluorescein diacetate) following the procedure of Zhao et al. (2005).