CHAPTER VIII 
GOOSEBERRY DISEASES 
CoMPARATIVELY few gooseberry diseases are of a serious 
nature; they are seldom sufficiently injurious to create anxiety. 
The American powdery-mildew and the leaf-spot are the most 
prevalent diseases of this fruit. The gooseberry, like the cur- 
rant, is affected by the European rust (white pine blister-rust), 
but is of less importance in this connection than the currant.- 
AMERICAN PowpDERY-M1LDEW 
Caused by Spherotheca mors-uve (Schw.) B. and C. 
The American gooseberry mildew is indigenous to the United 
States, where it is has been known for at least three-quarters 
of a century. It probably originated in this country on wild 
gooseberries before this fruit was brought under cultivation. 
It is believed on good authority that the fungus was carried 
from the United States to southwestern Russia about 1890, 
from which point it spread into neighboring European coun- 
tries. The disease made its first appearance in western Europe 
in 1900, when it was found in Ireland. Undoubtedly the mildew 
fungus was introduced from America about that time. In 1901 
it broke out again and became increasingly prevalent during 
the four years succeeding. With Russia and Ireland as centers, 
the disease soon became prevalent throughout Europe wher- 
ever gooseberries were cultivated. 
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