Protection of wood blocks treated with Trichoderma isolates selected on the basis of preliminary agar screening studies
E J B Tucker, A Bruce, H J Staines
Previously reported results of agar interaction screening studies for biocontrol agents of wood decay basidiomycetes showed two Trichoderma viride isolates, killed 16 of 19 target fungi (Tucker and Bruce, 1995). Testing of these isolates in wood was required to assess their performance at preventing decay of wood blocks. Standard testing of chemical wood preservatives is used to determine the toxic concentrations of preservative required to protect the wood against decay by basidiomycetes. As no ratified standards for testing biocontrol agents exist, two amended wood block testing standards were used to assess the two most effective Trichoderma isolates selected on the basis of preliminary agar screening studies. An agar based system similar to European Standard EN 113 (1980) and a soil block test based on the AWPA Standard 1413 (1977) were used with Scots pine and Sitka spruce pre treated with Trichoderma. Results indicated that wood blocks treated with Trichoderma isolates (T60) and (T110) were completely protected against decay by all the basidiomycetes tested irrespective of form of inoculum used (spores or mycelium) or timber species. Implications of the results for the use of agar plate interaction studies for screening biocontrol agents for subsequent use in wood block testing are discussed.
Keywords: BIOLOGICAL CONTROL; TRICHODERMA VIRIDE; BASIDIOMYCETES; AGAR SCREENING; STANDARD TESTS; EN 113; AWPA STANDARD 1413; PINUS SYLVESTRIS; PICEA SITCHENSIS