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7. The pseudoparenchymatous nature of the pycnidial wall, 
and the round opening,—the ostiolum. 
8. Lining the pycnidial cavity, the short, sharply pointed 
conidiophores on the ends of which the slender conidia are borne. 
9. The mycelial threads penetrating the tissue all about the 
pycnidium; the septation, contents and the branching of this mycelium. 
Make an enlarged pRawinG of a pycnidium with the surrounding 
host-tissue. 
Saprogenesis. There is no vegetative activity during the sapro- 
genic phase. The fungus winters over as spores in the pycnidia in the old 
leaves and stems which have been left in the field. These spores serve as 
the inoculum the following spring. 
Secondary Cycles. The conidia from the diseased leaves ooze 
from the pycnidium whenever moisture is present and are transfered by 
rain, tools or animals to the stems or other leaves. Secondary infections 
are repeated until the host is killed or removed. 
REPORT 
1. Make a list of all the Septoria leaf-spot diseases found on 
vegetables, to which you can find references in available literature. Give 
both the name of the pathogene and of the host. 
