ENUMERATION AND ABUNDANCE OF MYCOPHAGOUS PROTOZOA IN SOIL, WITH SPECIAL EMPHASIS ON HETEROTROPHIC FLAGELLATES

Mycophagous protozoa occur in most soils, but data on their quantitati ve importance are sparse, possibly due to a lack of suitable counting techniques. I describe a modification of the most probable number meth od for enumeration of mycophagous protozoa, especially flagellates, wi th indigenous soil fungi and yeasts as their food source in large indi vidual wells in 24-well microtitre plates. About 10(3) mycophagous fla gellates g(-1) dry soil were present in all soils examined. Mycophagou s flagellates responded by a 4-fold increase in a week after addition of glucose to soil. Their abundance and quick response to environmenta l changes suggest an important role for mycophagous flagellates in det ermining the size of populations of yeast cells and fungal conidia in soil. (C) 1998 Elsevier Science Ltd. All rights reserved.