plant surface microbiology.pdf

ccw
cc
hy
sl
rccw
hy
hy
7 Hartig Net Formation
cc
13 Root Surface in Ectomycorrhizas 221
a b
sl
ccw
sl
rccw
c cc
d
Fig. 8a–d. Cuticle-like suberin layer involved in mycorrhiza formation (Laccaria
amethystea-Picea abies). a Local digestion of the suberin layer and root cap cell wall, no
disturbance of cortical cell wall, vesicles probably containing enzymes (arrowhead,scale
1 mm). b Hypha splitting off the suberin layer and proliferating beneath, on the surface
of the cortical cell wall. Scale 0.5 mm. c Hypha penetrating between cell junction, suberin
layer partly digested (arrow) and partly preserved (arrowhead), lobed growth of hyphae
visible (arrow). Scale 1 mm. d Hyphae proliferating under the suberin layer (arrowheads)
show lobed branching typical of Hartig net structure (arrows). Scale 1 mm. cc Cortical
cell, ccw cortical cell wall, hy hypha, rccw root cap cell wall, sl suberin layer
Lobed growth of hyphae indicating the initialization of the Hartig net was
found in connection with the digestion of the cuticle-like layer (Fig. 8 c, d).
Thomson et al. (1989) described the formation of hyphal lobes at the base of
root hairs. Lobed hyphal growth on the root surface has been observed by
SEM (Jacobs et al. 1989; Brunner and Scheidegger 1992), but the connection to
sl
hy
hy
hy