Both fungal and bacterial endophytes have been isolated from the roots of
almost all hosts studied to date [Petrini 1991; Stone et al. 2000; Kobayashi
and Palumbo 2000; Sieber 2002; see Chaps. 2 (Hallmann and Berg),
3 (Kloepper and Ryu), and 7 (Sieber and Grünig)]. The assemblages of
endophytes that colonise a particular host vary both with habitat and host,
some even being adapted to very specialised habitats, e.g. the aquatic fungi
that colonise submerged roots (see Chap. 10 by Bärlocher). Recent molecular
methods enable better analyses of the geographical distribution of given