GROWTH AND BIODEGRADATION BY WHITE-ROT FUNGI INOCULATED INTO SOIL

The colonization of sandy loam soil following inoculation with spore suspensions of the white-rot fungi Phanerochaete chrysosporium ATCC 24725 and Chrysosporium lignorum CL1 was confirmed by an epifluorescence microscopy-image analysis method. These fungi and Trametes versicolor PV1 mineralized 3,4-dichloroaniline and benzo(a)pyrene in soil at concentrations up to 250 mug g-1. Successful inoculation and biodegradation required supplementary carbon sources. Addition of inorganic nutrients had no stimulatory effect, Glucose, hay, wood chips, pine bark, loam and peat all promoted growth and degradation but chopped wheat straw was the best substrate. Increasing the content of straw in the soil led to increased biomass and mineralization. The optimum ratio of straw: soil for mineralization was 1:4. Both strains sporulated within 7 days of inoculation before a further increase in hyphal growth but this had no effect on the mineralization rate. These results indicate that use of white-rot fungi in biotechnological soil treatment may be feasible.