Field tests for mold resistance with BHT and BTA added to bamboo preservatives

To improve resistance of bamboo preservatives against hydrolysis,light degradation,and oxidation degradation in outdoor applications,an antioxidant,butylated hydroxytoluene(BHT),and an ultraviolet ab-sorber,benzotriazole(BTA),were added to the preservatives propiconazole and tebuconazole and applied to four-year-old bamboo samples.Then,the influence on mold resistance was studied through 24 weeks of field tests.Results showed that for a 1.0% concentration of tebuconazole,adding BHT alone increased resistance against mold fungi on the up-face of bamboo from 19.14% to 34.84%;however,BTA alone reduced mold resistance.Nevertheless,adding both BHT and BTA to tebuconazole increased mold resistance to 42.75%.For a 1.0% propiconazole concentration,mold resistance on the up-face of bamboo with BTA alone increased from 14.4% to 37.23%,but BHT alone had little effect;adding both BHT and BTA to propiconazole,however,increased mold resistance to 54.12%.Thus,using BHT and BTA together could enhance mold resistance of both tebuconazole and propiconazole.