EFFECTS OF THE CORD-FORMING SAPROTROPHS HYPHOLOMA-AUSTRALE AND PHANEROCHAETE-FILAMENTOSA AND OF AMMONIUM SULFAMATE ON ESTABLISHMENT OF ARMILLARIA-LUTEOBUBALINA ON STUMPS OF EUCALYPTUS-DIVERSICOLOR

Freshly cut karri (Eucalyptus diversicolor) thinning stumps were simul taneously inoculated with the pathogen Armillaria luteobubalina and ei ther Hypholoma australe or Phanerochaete filamentosa. The stumps were inoculated with H. australe and and P. filamentosa either above- or be low-ground, and treated with either 40% (w/v) aqueous ammonium sulpham ate solution (AMS) or water. Fungal colonization 2 yr after inoculatio n was assessed. AMS treatment had several highly significant effects. Without AMS, neither biocontrol agent significantly reduced Armillaria colonization. However, with AMS, both P. filamentosa and H. australe significantly reduced Armillaria colonization, P. filamentosa being mo re effective. Below-ground inoculation was more effective in reducing Armillaria colonization than above-ground inoculation In the absence o f the biocontrol agents, AMS increased below-ground colonization by Ar millaria compared with non-AMS treated stumps, but reduced colonizatio n at and above ground level. Stump decay was increased, and coppice oc currence reduced, with AMS treatment. The naturally-occurring fungi St ereum hirsutum and Trametes versicolor fruited only on AMS stumps, whe reas Chondrostereum purpureum fruited only on non-AMS stumps. Fruiting by Hypholoma australe was enhanced by AMS, whereas Armillaria luteobu balina fruiting was significantly greater on non-AMS stumps.