SUMMARY

Gliocladium virens has shown good antagonism against decay fungi in agar medium and in wood blocks. Gliotoxin produced by G . virens is associated with biocontrol of some plant diseases, but its importance to biocontrol of wood-attacking fungi is unknown. We investigated the ability of gliotoxin-producing (GLT+) isolates of G . virens and gliotoxin-deffcient (GLT-) mutants of G . virens to inhibit growth of wood-attacking fungi in agar medium and to prevent decay in wood. The brown-rot fungi, Postia placenta and Neolentinus lepideus and the white-rot fungi, Trametes versicolor and Phlebia brevispora were completely inhibited by the GLT+ isolate and the GLT- mutants in agar medium. The GLT+ isolate also completely inhibited the growth of the brown-rot fungus, Gloeophyllum trabeum and the white-rot fungus, Irpex lacteus but the GLT- mutants caused lesser inhibition. The GLT+ isolate and GLT-mutants were ineffective in preventing growth of mold and stain fungi in dual agar culture. Pretreatment of wood blocks with a GLT+ isolate or GLT- mutant prevented decay by P . placenta. Likewise, the GLT+ isolate prevented decay by I . lacteus but the GLT- mutants did not. G . virens (GL-21) was grown on a sulfur containing medium l t pH 3.5 to enhance antibiotic production. However, inhibition of growth of decay fungi on agar medium containing culture filtrates was not enhanced. Decay was reduced in blocks treated with the culture filtrates but was not completely stopped. The filtrates were also ineffective in preventing growth of mold and stain fungi on wood.

Fungi

The following Basidiomycete decay fungi were used:

Brown-rot- Postia (= Poria ) placenta (Fr.) M. Lars. et. Lomb. [MAD-698], Neolentinus (= Lentinus ) lepideus (Fr.:Fr:) Redhead and Ginns [MAD-534] and Gloeophyllum trabeum (Pers. :Fr.) Murr. [MAD-617]; white-rot- Phlebia brevisporia Nakas. in Nakasone et Eslyn [HBB-7030-sP], Irpex lacteus (Fr. :Fr.) Fr. [HBB-7328-sp.], Trametes (= Coriolus ) versicolor L. ex Fr: Pilate [MAD-697], and Phanerochaete chrysosporium Burds. [ME-461].

The mold and stain fungi. used were:

Trichoderma sp., Aspirgillus niger van Tieghem, Penicillum sp.,Ceratocystis pilifera (Fries) Moreau Ceratocystis minor (Hedgcock) Hunt, and Aureobasidium pullulans (deBary) Arnaud.

• fungi and molds in buildings and their envelopes : Gliocladium viren against decay fungi in wood
• fungi: preservatives against fungi growth and mold decay : fungal biocontrol with G viren

1. Biodeterioration of wood
2. Biotechnology in the study of brown-and white-rot decay
3. Decay of wood and wood-based products above ground in buildings, Mechanism of Brown-Rot Decay: Paradigm or Paradox