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treatment. In an experimental plot in Dekalb county, untreated seed 
yielded tubers showing S7% infection of black scurf as compared with 
41% from treated seed. In a similar test in Lake county, there was 69% 
black scurf where untreated seed was used as compared with 6 to 13% 
where treated seed was used. 
Russet scab was found in Lake County. Its cause is not well under- 
stood. Silver scurf caused by Spondylocladium atrovirens was found on 
seed stock in Dekalb County. Leak caused by Pythium was found at 
Lafayette in freshly dug tubers kept in a warm place. 
A rather careful search of the state for the black wart disease accom- 
panied by educative propaganda to enlist the assistance of the growers and 
consumers in the search was made in cooperation with the federal plant 
disease survey by J. H. Weghorst. None of the disease was found. 
RADISH. 
Black-root attributed to Rheosporangium aphanidermatus was the most 
serious disease of radishes and was an important loss-producing factor 
in the culture of the white varieties especially in heavy clay soils. Not 
only are the blackened lesions objectionable in themselves, but are gen- 
erally invaded by rot-producing organisms. 
White rust caused by Cystopus candidus was prevalent in certain green- 
houses. A rot of the leaf bases due to Sclerotinia libertiana was also 
noted in greenhouses. 
RASPBERRY. 
Orange rust due to Gymnoconia peckiana was of widespread occurrence 
early in the summer. 
Anthracnose caused by Glocosporium venetum was very severe this year 
and was the worst disease of black raspberry in Indiana. It was especially 
important in Fountain County. In a plantation near Silverwood this dis- 
ease has been so severe that it has led to a method of culture in which 
the vines are forced until two or three good crops are secured after 
which they are destroyed and replaced. 
The non-parasitic yellows disease occurred locally. 
RHUBARB. 
Leaf-spot caused by Ascochyta rhei was of general occurrence. 
ROSE. 
Powdery mildew (Sphaerotheca pannosa) was very destructive in 
greenhouses, especially on the Killarney variety. It was also prevalent on 
the Ramblers in June. 
Black spot caused by Actinonema rosae was found in the greenhouse crop 
and was most serious on the Russell variety. 
RYE. 
Twenty-eight fields in 17 counties were examined in the course of the 
federal cereal disease survey. Septoria on the heads was reported from 
