The paper present results of screening tests of filamentous fungi occu
ring in surface Danube water and in wells. In the course of 1990 - 199
2 altogether 158 samples were investigated. For the purpose of Deutero
mycetes isolation samples of volume 1 ml were inoculated on Czapek - D
ox agar, Sabouraud agar and malt agar plates supplemented with tetracy
cline 20 mg.l-1. The cultivation has been carried out for 30 days at r
oom temperature on day-light. That prolonged cultivation period proved
to be very useful for micromycetes identification. From the isolated
Deuteromycetes 45 genera were identified. The majority of them was hit
herto not described in underground water sources. The results confirm
the assumption, that contamination of underground water sources by soi
l Deuteromycetes is getting more frequent. This phenomenon is in close
conection with the general deterioration of environment.