Two month-old in vitro tomato plants were inoculated by applying Xcv cell suspension to leaves using micropipettes. After inoculation, three plants were left without any treatment, and BLS was allowed to develop. Lentinula edodes mycelia culture filtrate was applied in the same way to tomato foliage either 24 h before or 24 h after Xcv inoculation. Another set of three plants was treated with 100 ppm streptomycin sulfate (positive control) 24 h after Xcv inoculation. Three plants were left un-inoculated but sprayed with sterile saline (un-inoculated control). The effect of Lemcf foliar application in vitro was determined by applying Lemcf on uninoculated plants (Lemcf). There were three BRs of Lemcf, each BR was applied in duplicate, and the mean of two values was used. The treated leaflets on every plant were counted, and the plants were visually observed daily for BLS symptoms or plant response to Lemcf application. The infected leaflets were enumerated 14 d after treatment and converted to the percentage of treated leaflets. The experiment was repeated twice with three BRs in each treatment group and control. The data from un-inoculated controls were not included for statistical analysis. The treatment means were separated by the least significant test at 5% probability. According to the LSD test, there was no significant difference among treatments in three trials; thus, the data were pooled and presented as one trial.