STRAWBERRY DISEASES 423 
amass themselves beneath the cuticle of either surface of the 
leaf, and from these masses conidiophores bearing conidia 
arise. These spores develop, are scattered and produce in- 
fections through- 
out the summer; 
with the advent 
of winter conidial 
formation ceases, 
but the mycelium 
remains alive in 
the leaves until 
the following 
spring. At this 
time a new crop of 
conidia develop, 
which begin the 
cycle anew by in- 
fecting again the 
strawberry plants. 
Should any of 
these spores per- 
chance fall on the common cinquefoil, the disease would be 
produced. It should also be mentioned that this plant acts 
as a weed-host, carrying the fungus through the winter and 
furnishing a source of the inoculum in the spring, as does the 
strawberry plant itself. 
It has been noted that conidial production ceases in the fall 
and that the winter is spent as mycelium in the old leaves. 
Toward winter the fungus makes preparations for other means 
of hibernation. Masses of mycelium appear on the surface 
of the leaf; these are sclerotial bodies which are capable of 
producing conidia in the spring following. A third means 
of over-wintering is by the perithecia; these arise in the fall, 
but remain immature until March or April, when mature asco- 
Fig. 123. — Strawberry leaf-spot. 
