
New York AGRICULTURAL EXPERIMENT STATION. 153 
e 
EXPERIMENTS WITH FUNGICIDES. 
Potassium sulphide for the gooseberry mildew. 
Potassium sulphide contrasted with soda hyposulphite and 
calcium sulphide for the apple scab. 
PorassiumM SULPHIDE FOR THE GOOSEBERRY MILDEW. 
At the suggestion of Dr. J. C. Arthur,* formerly botanist to the 
Station, a series of trials was made with potassium sulphide as a 
preventive of injury from the disease of the gooseberry plant 
- commonly known as “ mildew,” and due to a fungus parasite known 
to science as Sphwrotheca Morsuve B. and C. The substance was 
applied in solution at the rate of one-half and one-fourth ounce to 
the gallon respectively, commencing May 3, or as soon as the 
leaves had begun to expand, and the application was repeated 
after every hard rain until July 24, nine sprayings having been 
made inall. The experiment was made upon a row of the Industry 
gooseberry containing five plants, and upon a plat of seedlings 
numbering 282 plants. 
Toward midsummer the effect of the spraying became dis- 
tinctly visible in the deeper green foliage and more rapid growth 
of the treated plants. On June 23 the two plants of the Industry 
gooseberry that received the sprayings were noted as being 
entirely free from mildew, with the exception of a trace of 
it observed on a single fruit, while the three not treated were 
quite badly affected. The fungus appeared as a downy coating 
near the termini of the new shoots and also upon the berries. 
The new growth as well as the crop of fruit was very perceptibly 
greater on the treated plants. At this time the bed of seedlings 
had not been perceptibly attacked by the fungus. 
On July 16 the seedling plants were found to be consid- 
erably affected, and an examination showed that in the row 
treated with the sulphide, at the rate of half an ounce to the 
gallon, only one plant exhibited signs of mildew out of a total of 
sixty —about 1.7 per cent; in the row treated at the rate of 
one-fourth ounce to the gallon, three plants were affected out of 
* For results secured with this substance by Dr. Arthur in 1887 see 
Report New York Agricultural Experiment Station, 1887, pp. 348-52. 
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