Effect of mixtures of carbon disulfide and methylisothiocyanate on survival of wood-colonizing fungi

The fungitoxicity of carbon disulfide (CS2), methylisothiocyanate (MITC), or a mixture of these two gases, to selected wood-degrading fungi was studied by using a fumigation apparatus. Both gases are important decomposition products of metham sodium, the most commonly used fumigant for internal treatment of large wood members. Carbon disulfide (up to 8,000-9,000 ppm) was mildly toxic to most of the test fungi, and MITC (up to 18 ppm) was uniformly toxic. A combination of sublethal levels of both gases (3,000-4,000 ppm CS2/5 ppm MITC) was more toxic than either chemical alone. The results suggest a synergism between various metham sodium decomposition products, and this interaction may account for the protection afforded by this treatment. Further studies of other decomposition products are suggested