It has been demonstrated that low doses of fluorine (from 100 to 200 mgF·kg-1 of soil) had a positive
influence on counts of the analyzed microorganisms and on the activity of the examined soil enzymes.
Under the influence of such low amounts of fluorine, the number of actinomyces and the activity of urease
increased in soil tested after the harvest of winter rape and yellow lupine, the latter being a catch crop sown
after maize.