Ribera Javier, Fink Siegfried, Bas Maria Del Carmen, Schwarze Francis W M R
Applied Wood Materials, Empa, St. Gallen, Switzerland.
Professur für Forstbotanik, Albert-Ludwigs-Universität Freiburg, Freiburg im Breisgau, Germany.
PLoS One. 2017 Apr 5;12(4):e0174335. doi: 10.1371/journal.pone.0174335. eCollection 2017.
The production of new generation of wood preservatives (without addition of a co-biocide) in combination with an exchange of wood poles on identical sites with high fungal inoculum, has resulted in an increase of premature failures of wood utility poles in the last decades. Wood destroying basidiomycetes inhabiting sites where poles have been installed, have developed resistance against wood preservatives. The objective of the in vitro studies was to identify a Trichoderma spp. with a highly antagonistic potential against wood destroying basidiomycetes that is capable of colonizing Cu-rich environments. For this purpose, the activity of five Trichoderma spp. on Cu-rich medium was evaluated according to its growth and sporulation rates. The influence of the selected Trichoderma spp. on wood colonization and degradation by five wood destroying basidiomycetes was quantitatively analyzed by means of dry weight loss of wood specimens. Furthermore, the preventative effect of the selected Trichoderma spp. in combination with four Cu-based preservatives was also examined by mass loss and histological changes in the wood specimens. Trichoderma harzianum (T-720) was considered the biocontrol agent with higher antagonistic potential to colonize Cu-rich environments (up to 0.1% CuSO4 amended medium). T. harzianum demonstrated significant preventative effect on wood specimens against four wood destroying basidiomycetes. The combined effect of T. harzianum and Cu-based wood preservatives demonstrated that after 9 months incubation with two wood destroying basidiomycetes, wood specimens treated with 3.8 kg m-3 copper-chromium had weight losses between 55-65%, whereas containers previously treated with T. harzianum had significantly lower weight losses (0-25%). Histological studies on one of the wood destroying basidiomycetes revealed typical decomposition of wood cells by brown-rot fungi in Cu-impregnated samples, that were notably absent in wood specimens previously exposed to T. harzianum. It is concluded that carefully selected Trichoderma isolates can be used for integrated wood protection against a range of wood destroying basidiomycetes and may have potential for integrated wood protection in the field.
在过去几十年中，新一代木材防腐剂（不添加辅助杀菌剂）的生产，以及在真菌接种量大的相同地点更换木杆，导致木质电线杆过早失效的情况有所增加。栖息在电线杆安装地点的木材腐朽担子菌，已对木材防腐剂产生了抗性。体外研究的目的是鉴定一种对木材腐朽担子菌具有高度拮抗潜力、能够在富铜环境中定殖的木霉属菌株。为此，根据五种木霉属菌株在富铜培养基上的生长和产孢率，评估了它们在富铜培养基上的活性。通过木材样本的干重损失，定量分析了所选木霉属菌株对五种木材腐朽担子菌在木材定殖和降解方面的影响。此外，还通过木材样本的质量损失和组织学变化，研究了所选木霉属菌株与四种铜基防腐剂联合使用时的预防效果。哈茨木霉（T-720）被认为是具有较高拮抗潜力、能够在富铜环境（高达0.1%硫酸铜改良培养基）中定殖的生物防治剂。哈茨木霉对木材样本上的四种木材腐朽担子菌显示出显著的预防效果。哈茨木霉与铜基木材防腐剂的联合作用表明，在与两种木材腐朽担子菌共同培养9个月后，用3.8 kg/m³铜铬处理的木材样本重量损失在55%至65%之间，而先前用哈茨木霉处理过的容器重量损失则显著较低（0%至25%）。对其中一种木材腐朽担子菌的组织学研究表明，在铜浸渍样本中，木材细胞出现了典型的褐腐真菌分解现象，而在先前接触过哈茨木霉的木材样本中则明显没有这种现象。得出的结论是，精心挑选的木霉分离株可用于对多种木材腐朽担子菌进行综合木材保护，并且在实地木材综合保护方面可能具有潜力。
