Abstract
Newly designed testing method was proposed to evaluate the effectiveness of anti-mold and anti-sapstain formulations in the field.
Freshly sawn pine (Pinus densiflora Sieb. et Zucc.) boards were dipped in the solution of formulation for 30 seconds and subjected to outdoor exposure in piling with stickers on June 6, 1988. Thirty replicates were prepared for each treatment. Each test board was visually inspected after 1 and 2 weeks' and 1, 3, 6 and 12 months' exposure to evaluate the changes in persistence of effectiveness with time.
Among 5 formulations tested, a mixture of 2-(Thiocyanomethylthio) benzothiazole (TCMTB) + Methylene his thiocyanate was the most effective at 1% of the formulation after 6 months' exposure. Two alternative candidates [TCMTB+3-Iodo-2-propynyl butyl carbamate, 4-Chlorophenyl-3-iodo-propargyl formal+2-(4-Thiazolyl) benzimidazole] were satisfactorily effecitve at 1% of the formulations in protecting timber for 3 months.
Conventional commercial agents which contained sodium trichlorophenate or trichlorophenol as a main active ingredient were less effective at an actual treating strength in controlling the growth of mold and sapstain fungi on wood.
The present testing method was proved to be useful for not only evaluating the efficacy of anti-sapstain formulations but also comparing the persistence of efficacy among the formulations tested.
