LITERATURE ON BUNT OF WHEAT. 15 
well as dry-heat sterilization, held an important place in subsequent 
vestigations. 
Experiments by Kellerman and Swingle in 1889 (196) and Keller- 
man in 1890 to 1896 (191-194) led them to conclude that of the many 
methods of seed treatment tested by them, the hot-water method 
was best for general use. Their experiments also established the 
practical value of potassium sulphid as a preventive of oat smut 
and the covered smuts of wheat and barley. The results of these 
experiments indicated that potassium sulphid reacted favorably 
on the germination of the seed and on the early growth and vigor 
of the plants. It was found that the promptest germination resulted 
from seed soaked 24 hours in a 0.5 per cent solution of potassium 
sulphid where this test was made immediately following treatment. 
“The prompt germination and stimulation of seedling vigor were 
considered as factors favoring rapid growth and hence possible 
escape from infection. 
_ Arthur in 1890 (25) concluded that seed wheat was practically 
/ uninjured by hot-water at 54° C. for 5 minutes. Experiments by 
Hickman (1/57) supported Kellerman’s findings as to increased yield 
' following treatment with hot water. Harwood and Holden (1/43) 
found that a 10-minute treatment at a temperature of 57.7° ©. or 
less produced no change in germinative energy. 
- Kirchner (201) reviews the results of all experimental study of 
the Jensen method and gives the data resulting from his own experi- 
_ ments, which. while not extensive, were carried out with such careful 
regard for all factors and details as to give the results high value. 
_ His conclusions favor the Jensen method. 
Geuther (133) suggested the use of formaldehyde as a sterilizing 
_ agent in combating smuts in general and supported his recommenda- 
tion by experimental evidence. Bolley (50) gives the results of 
laboratory and field experiments in the treatment of seed wheat for 
the years 1893 to 1896, inclusive. In these experiments he used 
copper sulphate, mercuric chlorid, hot water, and formaldehyde. 
His is the first recorded use of formaldehyde in the United States as a 
fungicide for the prevention of bunt. As to the efficacy of a bunt 
preventive, he considered corrosive sublimate superior to all other 
Ratinivides, with the possible exception of formaldehyde, which at that 
time had received only preliminary tests. 
Kittlauss (2/3) reported on extensive experiments regarding the 
mnjury to seed grain from the use of copper sulphate. His opinion 
was that the degree of damage was to some extent dependent on injury 
to the seed coat. 
Falke (106) found that an application of 0.5 per cent copper sul- 
_ phate for a period of 16 hours produced no injury when the seed coat 
was uninjured and notes that injury was greater to machine-threshed 
_ than to flail-threshed grain. 
- From 1900 to 1903 Farrer (109, 110, 113, 114) carried on extensive 
seed-treatment experiments, from which he concluded: (1) That 
bunty seed wheat could not be sufficiently cleaned by repeated 
washings in water to make its use safe. (2) The spores within 
unbroken bunt balls could not be killed by any treatment that the 
wheat could survive. (3) Copper sulphate was fairly efficient in 
killing the spores on the grain, and, although it was more injurious 
to the seed than either formaldehyde or mercuric chlorid, it furnished 
greater protection against reinfestation. (4) Formaldehyde was cheap, 
