Mar. io, 1923 
Rosette Disease of Wheat and Its Control 
797 
later sowings. No exact explanation of this irregularity in the disease 
curves in the two seasons can be given, but it is noted that these curves 
follow closely the temperature curves for the germination periods for the 
several sowings. This relationship is very suggestive of a parasitic cause. 
SUMMARY 
This paper deals with the rosette disease of winter wheat, which was 
first reported in 1919 from Madison County, Ill., and a little later from 
Indiana under the name of take-all and later so-called take-all. 
Investigations show that this disease is not the same as the take-all 
and footrot type of diseases which have occurred for many years in 
Australasia and Europe and have now been found in the United States. 
The rosette disease has recurred in the field each year since it was 
reported, but the typical plant symptoms have not been reproduced 
satisfactorily under ordinary greenhouse conditions or in the field out of 
the regular season for winter wheat, thus reducing the problem to a 
seasonal one until such time as special methods have been perfected. 
The origin of the rosette disease of wheat is unknown. It is believed 
that the disease has been present in certain of the infested areas for a 
considerable length of time. 
So far as known this malady occurs only in the States of Illinois and 
Indiana. 
Under conditions favorable for the disease it may be very destructive, 
causing a reduction of 75 per cent or more in yield in experimental plots. 
Under conditions favorable for the host, remarkable recovery from the 
disease may result and losses may be very slight. Forty per cent reduc¬ 
tion in yield is not uncommon under farm conditions. 
So far as definitely known the disease occurs only in certain varieties 
of winter wheat. Certain symptoms resembling the rosette disease have 
been observed in certain varieties of spring wheat and to a slight extent 
in barley and rye. No other grains or crops under experiment have de¬ 
veloped symptoms resembling the disease. 
The disease may cause a spotting in affected fields or it may be dis¬ 
tributed rather generally over the fields. These spots or patches of dis¬ 
eased plants occur independent of any particular soil type or topographic 
condition in the field. 
The most constant or characteristic plant symptoms consist of: (1) 
an arrested spring development, (2) an excessive tillering which results in 
a rosette appearance, and (3) a dark blue-green color of the foliage in com¬ 
bination with 1 and 2. 
The take-all and footrot type of diseases cause field spotting, which is 
similar to the spotting caused by the rosette disease, except that the for¬ 
mer diseases seem to appear a little later in the spring. 
In the take-all and footrot type of diseases no excessive tillering has 
been noted, and diseased plants turn yellow shortly after the spring 
growth begins. Such plants gradually bleach and dry up, usually stand¬ 
ing erect and assuming a stiff, wiry posture. Sometimes older plants 
break over at the base. On the other hand, plants affected by the rosette 
disease, when killed early, form a flat or drooping tuft of brown dead 
leaves which do not pass through a yellow stage. 
A black “mycelial plate” is rather characteristic of the take-all and 
footrot type of malady, but this has never been found associated with the 
rosette disease. 
