Jan. 26,1924 
The Black-Bundle Disease of Corn 
179 
The seed ears referred to in Table I were the first generation crosses 
(artificially pollinated) of different strains of Funk Ninety Day, and when 
tested on the germinator, 30 kernels from each, showed 100 per cent 
vigorous seedlings and no evidence of rotting. Hence, it was thought 
that all were healthy. However, on September 11, row 3 (seed-ear 
5824) was found to be uniformly diseased. As shown in Table I, there 
is a decrease in number of good ears and an increase in number of nub¬ 
bins, barren stalks, and stalks with purple leaves, in comparison with 
adjacent rows on each side. Numerous stalks in row 3, when cut open 
at time of harvest, showed the characteristic blackened bundles. Usually 
in the latitude of central Illinois, the time of appearance of any easily 
recognized symptom of this disease is about the third week of August. 
At that time the first purple leaves usually appear, and barren and 
prolific stalks can be identified. 
Symptoms as described and certain related observations have been 
noted for a number of years. For example, in the fall of 1917, an ear 
row of Funk Ninety-Day com in a breeding plat showed certain out¬ 
standing characteristics. The plat was located on clover sod that had 
not grown com for three years. The soil was uniform and of medium 
fertility. The ear from which the row in question was grown was of 
fine appearance in every respect and had shown strong germination on 
the germinator with no evidence of rotting. Hence it had been selected 
as a choice ear for breeding stock. During the early part of the season 
the plants showed no signs of disease. Attention was first directed to 
this row early in September following a light frost. All of the plants in 
this row were slightly injured by the frost, while the plants in adjacent 
rows showed no injury whatever. The row also contained an unusually 
large proportion of purpled plants and an abnormally large percentage 
of barren stalks. Further, on cutting open the stalks, it was found 
that most of the barren stalks and those with nubbins as well as some 
with good ears contained abundant blackened bundles. The row yielded 
only about one-half as much as the best adjoining rows. Seed ears for 
use in an experiment the following year (1918) were selected from this 
row, both from plants showing blackened bundles and from those which 
apparently were healthy. Eleven ears were thus selected, two from the 
apparently healthy plants and nine from the diseased ones. These ears 
were tested on the germinator in the usual way and all showed 100 per 
cent of strong germination, with no evidence of rotting. In 1918, these 
11 ears were planted in ear rows along with 6 other ear rows from ap¬ 
parently healthy ears as controls. Unfortunately, the proportions of 
plants showing purple-stalk and black-bundle symptoms were not noted 
in 1918, but careful yield data were taken and computed to acre yields 
on a uniform moisture basis. The nine diseased rows produced an aver¬ 
age of only 53.1 bushels per acre compared with 77.8 and 72.8 bushels 
per acre from the rows from the two specially selected ears and from the 
six control rows, respectively. 
Certain earlier manifestations in the development of com plants, such 
as abnormally fast growth in height or diameter, indicate that such 
plants later on are likely to produce symptoms of purple-stalk and black- 
bundle diseases. Some evidence that abnormally fast growth in height 
is an indication of disease was brought out from data obtained in 1919. 
Three hundred and twenty-seven plants were measured for height 36 
days after planting and were grouped in quartiles according to height, 
