150 Summary of Agricultural Experiments, [may 
out at Bristol University by Messrs. J. H. Priestley and A. E. Lech- 
mere. Specimens of swedes attacked by this disease were sent 
from the neighbourhood of Taunton to the University of Bristol. 
The first indication of attack was described as being the 
appearance of a small crack on the side of the root, almost as 
if made by a hoe ; this crack gradually widened, the interior 
being filled with slimy, rotting tissue, and in many cases the 
plant died. By infecting pieces of fresh swede and turnip with 
slime from a diseased root, the decay was shown to be due to bacterial 
action and not to an injury alone. Several organisms were isolated, 
and the one to which the disease is attributed is considered to be 
probably Bacillus oleraceae (Harrison), the cause of soft black rot of 
cabbages, but also closely allied to Pseudomonus destrnctans (Potter), 
which causes soft white rot in turnips, Sec. It is suggested, after con- 
sideration of its appearance on various culture media, that these two 
organisms may be different growth forms of the same parasitic species. 
The cultures show that the organism is capable of existence as a 
saprophyte, and this means that it may continue to exist in the soil, 
on rotting tissue, long after the crop itself has been removed. This 
makes the question of the extermination of the disease a difficult 
one ; one obvious precaution is to lengthen the period as far as pos- 
sible between successive crops of the turnip and cabbage kind when 
the disease has once appeared. It seems capable of growing in both 
an alkaline and an acid medium, so that it does not seem clear that 
any particular dressing applied to the soil would affect its increase. 
In this particular case of infection the disease was prevalent at the 
same time, and under the same conditions, as nnger-and-toe, which 
would indicate insufficient lime in the soil. The practical question of 
the treatment of the soil would, however, need to be investigated by 
field experiments. 
Wart Disease of Potatoes (Wart Disease of Potatoes, Harper Adams 
Agric. Coll., 1910). — These experiments are included among those on 
which a report appeared in the Journal, April, 191 1, p. 42. The present 
bulletin contains the results of inquiries as to the method of infection 
and of the spread of the disease, and details of the experiments carried 
on at the Harper Adams College in 1909 and 19 10 to discover resistant 
varieties of potatoes, and a means of checking the disease by fungicides. 
The yields of all the varieties resistant to the disease that have been 
grown are shown. The fungicide dressings that were tried consisted 
of quicklime, gas lime, sulphur, salt, soot, copper sulphate, sodium 
borate, potassium sulphide, black sulphur, ferrous sulphate, strawsonite. 
and a proprietary Black Scab Compound. None of them was found to 
be of any value. 
