Introduction to Fungi, Third Edition

PLEOSPORALES
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Fig17.12 Helminthosporium velutinum. (a) Conidiophores and conidia. (b) Detached conidia. (c) Details of conidial development.
Note the narrow channels in the wall through which cytoplasm passes to the developing conidia.This type of development is tretic.
(b)and(c)tosamescale.
different from the outer wall surrounding the
entire conidium (White et al., 1973). This can be
readily seen even with the light microscope
because the individual conidial cells of
Drechslera, Helminthosporium and Bipolaris appear
like peas in a pod (Figs. 17.12, 17.13, 17.16). In
Curvularia, the conidial septa are of the normal
(euseptate) type (Fig. 17.14).