MINERALIZATION OF 2,4-DICHLOROPHENOL BY ECTOMYCORRHIZAL FUNGI IN AXENIC CULTURE AND IN SYMBIOSIS WITH PINE

Experiments were conducted to determine if two ectomycorrhizal fungi ( Paxillus involutus and Suillus variegatus) could degrade 2,4- dichloro phenol both in axenic liquid culture and during symbiosis with a host tree species Pinus sylvestris. Both fungi readily degraded 2,4- dichlo rophenol in batch culture with similar rates of mineralization on a bi omass basis. Up to 17% of the 2,4- dichlorophenol was mineralized over a 17 day period. Growth of the fungi in symbiosis with P. sylvestris is stimulated greater mineralization than when fungi were grown in abs ence of the host. S. variegatus was more efficient than P. involutus ( in the presence of P. sylvestris) at mineralizing 2,4- dichlorophenol. Mineralization in vermiculite culture was greatly reduced compared to liquid culture. Only 3% of the 2,4- dichlorophenol was mineralized af ter 13 days in vermiculite culture for the most efficient degrading tr eatment. (C) 1997 Elsevier Science Ltd.