Effect of Duramycin on Some Isolates of Trichoderma viride

IN work on soil fungus populations by soil dilution plating and other cultural techniques, it is sometimes necessary to incorporate some fungistatic agent with the culture medium so as to suppress excessive development on the isolation plates of fast-growing fungi that otherwise would overrun most of the other colonies. A fungus commonly causing trouble in this way is Trichoderma viride Fr., and so the observation by Vaartaja 1 that the antibiotic duramycin inhibited the growth of T. viride even at 20 mg/l. seemed worthy of following up. Unfortunately, Lindenfelser et al. 2 were unable to confirm Vaartaja's observation, as they found the minimum concentration of duramycin inhibiting growth of T. viride to exceed 100 mg/l.