ABSTRACT
Among the microbial groups, protozoa are involved in pivotal processes in both aquatic
and terrestrial ecosystems. In soil ecosystems, protozoa are conspicuous (Berthold and
Palzenberger 1995), serving as consumers and prey for other soil microorganisms (Clarholm
1981), influencing the development and metabolic activities of bacterial communities (Pussard
et al. 1994; Griffiths et al. 1999), and concomitantly increasing plant biomass (Kuikman et al.
1990; Alphei et al. 1996). The role and diversity of protozoa in the soil has been the subject
of recent reviews (Adl 2003; Adl and Gupta 2006). An extensive literature was synthesized
in two earlier reviews (Foissner 1987; Darbyshire 1994), and Bonkowski (2004) reviewed
the interactions of protozoa with plant roots.
