Jan. 1, 1925 
A Study of Variability in the Burt Oat 
27 
of character phases in each of the eight 
strains were pwiled and tied together 
in a bundle. When cured the heads 
were removed, labeled with the strain 
number, the class or character phase, 
and the individual plant number, and 
shipped to Manhattan for study. 
The general plan was to describe at 
least 25 primary kernels from each 
plant grown in 1920. Usually all of 
ihe primary kernels on the main panicle 
were described; but where the main 
panicle did not provide 25 kernels the 
additional number required was taken 
from a secondary panicle. The secon¬ 
dary kernels of the spikelets were not 
described as such in this study but only 
the method of their disjunction. The 
kernels were taken from the panicle in 
a definite order from the base to the 
top. It was thought that some defin¬ 
ite and progressive variation might 
nxist within tke panicle, but the results 
obtained do not indicate such an ar¬ 
rangement. The same characters des¬ 
cribed in the parental material were 
used in the descriptions of the progeny 
kernels of the 1920 crop, namely, (1) 
spikelet disarticulation; (2) floret dis¬ 
junction; (3) basal hairs; (4) awns; 
and (5) lemma color. 
Special forms were devised for re¬ 
cording descriptions of the kernels, 
check marks being made under the 
proper headings. There were slight 
differences in the descriptions of the 
kernels grown at the two stations be¬ 
cause the Manhattan material was de¬ 
scribed first and as the work progressed 
several minor changes were made. 
At first no distinction was made be¬ 
tween the abundant long and the abun¬ 
dant midlength subclasses of basal 
hairs. This distinction was first made 
toward the end of the study of the 1920 
Manhattan material and was contin¬ 
ued throughout the description of the 
Akron material. Shortly after the de¬ 
scriptions of the Akron material was 
started it appeared advisable to divide 
the brown color class into dark brown 
and light brown. No intermediate 
subclass in floret disjunction was recog¬ 
nized in describing the original kernels, 
but it was used when describing the 
kernels of plants grown in 1920. 
The percentage of kernels described 
as being intermediate (heterofracture) 
for floret disjunction was much higher 
in the 1920 crop from Akron than in 
the 1920 crop grown at Manhattan. 
This may be partly owing to differences 
in individual judgment, the Manhattan 
and the Akron material in 1920 being 
described by two different persons. 
METHODS IN 1921 
In planning the 1921 experiments it 
was decided to grow all of the classes 
and subclasses of kernels representing 
distinct individual characters and as 
many different combinations of these 
as possible. The kernels from each 
plant grown in 1920 were carefully ex¬ 
amined and as complete an array as 
possible of these characters and combi¬ 
nations of characters w'as chosen from 
each of the nine parental strains for sow¬ 
ing in 1921. In making these selections 
never less than 5 nor more than 10 
kernels of a single subclass from any one 
plant were sown. Tor example, if in 
studying floret disjunction in the 25 
kernels from plant No. 5211-5-10 
(Kansas strain No. 5211, group 5, plant 
No. 10) 15 kernels were designated by 
disarticulation and the other 10 kernels 
by basifracture, probably 10 kernels of 
each of these two types of floret dis¬ 
junction were selected for growing. 
Those of one disjunction type would 
be grown in 1921 as No. 5211-5-10-1 
and those of the other type as 5211-5- 
10-2. All of the kernels representing a 
given class or subclass sown in the 1921 
experiments at Akron came from the 
same parent plant. As a rule but few 
plants derived from any one original 
strain and bearing the same classifica¬ 
tion were used for seed, as otherwise 
the material would soon have become 
too extensive. 
The same general plan was followed 
in making the kernel selections from 
the 1920 plants grown at Manhattan, 
although some classes were chosen for 
studying the inheritance of a particular 
character, or combination of characters, 
without describing all of the other 
characters of the kernels. 
Approximately 800 kernels were 
selected and sown in the 1921 experi¬ 
ments at Akron. The weather was 
very dry and grasshoppers did con¬ 
siderable damage to the plants. 
Between 500 and 600 kernels were 
selected, described, and sown in 
the 1921 experiments at Manhattan. 
Weather conditions were favorable and 
the crop made a normal growth. How¬ 
ever, a serious infestation of chinch 
bugs occurred in late June and early 
July and greatly checked the growth of 
the plants, with the result that a con¬ 
siderable percentage of the kernels 
failed to reach their full development. 
The general procedure in conducting 
the 1921 experiments was the same at 
the two stations. The same notes on 
plant characters were taken as in 1920. 
