抄録
The purposes of this report were to impove the efficacy agaist a brown rot fungus, Tyromyces palstris, by mixing various cobiocides to the inorganic preservative reported in prior paper. The efficacy of the preservatives was estimated by the method of JIS A 9201. From the experimental results, some cobiocides were selected and were subjected to further simulated field and field tests. Tebuconazole had the highest synergic effect as a cobiocide. Boric acid which was important component of ACB and CCB approved in Europe was also a superior cobiocide.
In the field test, the preservative prepared by the mixing the inorganic copper solution 20, boric acid 56 and tebuconazole 1 had the comparable effect to CCA-type 1 at the same copper retention.
The synergic effects became higher in order tebuconazole, DDAC, boric acid in the field test. In the simulated field test, tebuconazole had also the highest effect, however, DDAC and boric acid had considerably lower effects.
The difference between these results was due to the participation of copper-tolerant fungi. The simulated field test included the copper-tolerant fungi and gave the severer test condition to the treated wood than the field test gave.
From these results, it was considered that the simulated field test could be used instead of the field test with reducing greatly test period.
