May i5 ,1925 Inheritance of Botanical Characters in Barley 929 
awn, are located in different chromo¬ 
some pairs. A different relation was 
found to exist, however, between some 
of these factors and the factors for 
early versus late heading and the fac¬ 
tors for resistance and susceptibility 
to the spot blotch disease. 
Table XX.— Distribution of black- 
glumed and white-glumed F 3 lines for 
date of heading; cross SvanhalsX 
Lion , 1923 
Heading date 
Color of glume 
Early 
Segre¬ 
gating 
Late 
Total 
Black... 
i 
14 
3 ! 
24 
White.. 
13 
26 
12 ; 
51 
Total_ 
20 
40 
15 ; 
75 
Early and late heading in rela¬ 
tion to other characters. —Fifty- 
one white glumed F 3 lines were grown 
from the cross SvanhalsX Lion. Of 
these 51 lines, 13 bred true for early 
heading, 26 segregated for early versus 
late, and 12 bred true for late (Table 
XX). Of 24 lines breeding true for 
black glumes, 7 lines bred true for 
early heading, 14 segregated for early 
versus late, and 3 bred true for late. 
These results show the independence 
of the character pairs early versus late 
heading and black versus white glumes. 
The data for the date of heading of the 
rough-awn and smooth-awn F 3 families 
indicate here also an independence 
(Table XXI) although the number of 
lines is small in each group. 
Table XXI.— Distribution of rough- 
awn, inter mediate-smooth-awn, and 
smooth-awn F 3 lines for date of 
heading; cross SvanhalsX Lion, 1923 
Heading date i Total 
_ num- 
Awn class 
Early 
Segre¬ 
gating 
Late 
ber of 
fami¬ 
lies 
Rough_ 
Intermediate- 
S 
A 
8 
23 
smooth... 
5 
8 
2 
15 
Smooth_ 
4 
16 
3 
23 
Total.. 
17 
31 
13 
61 
Of the 135 F 3 lines grown from the 
cross SvanhalsX Lion, 64 were 6- 
rowed and 24 were homozygous 2- 
rowed. In the 6-rowed group, 20 lines 
bred true for early heading, 11 headed 
late, and 33 segregated (TableXXII). 
In the 2-rowed group the conditions 
are reversed; more lines bred true for 
late heading than for early heading. 
Since the 6-rowed parent in this cross 
is the early parent, the factors for 6- 
rowed and early heading went into the 
cross together and tend to stay to¬ 
gether. The linkage intensity, how¬ 
ever, is quite low. 
Table XXII.— Summation of the 6- 
rowed and 2-rowed F 3 families with 
respect to the characters early heading 
and late heading; cross Svanhals X 
Lion, 1923 
Six-rowed families 
VV EE 
VV Ee 
VV ee 
Total 
Observed- 
20 
33 
11 
64 
Calculated 42 per 
cent C. 0. 
21.5 
31.2 
11.3 
64 
j 
Two-rowed families 
vv EE 
vv Ee 
vv ee 
Total 
Observed- 4 
12 
8 
24 
Calculated 42 per | 
cent C. 0_ 4.2 
11.9 
8.1 
24.2 
X 2 “less than 1 . P=Good fit. 
In calculating the linkage intensity, 
genotypes are assumed for the groups 
as follows: 
Group 
F type°" F3 breeding behavior 
a _ 
b _ 
VV EE.. 1 Breeding true for early heading 
and 6-rowed. 
VV Ee___ Segregating for date of heading, 
breeding true for 6-rowed. 
VV ee_ Breeding true for late heading 
and 6-rowed. 
vv EE... Breeding true for early heading 
and 2-rowed. 
vv Ee_ Segregating for date of heading, 
j breeding true for 2-rowed. 
1 vv ee_ Breeding true for late heading 
and 2-rowed. 
c. 
c . . 
b _ 
a _ 
In independent inheritance, the 
groups a, b, and c are to each other 
r~ 
as 1:2:1 or -y/—: 1 equals 1:1, y: 1 
equals 1:1, and 1 equals 1:1. If 
one combines these three terms, the for¬ 
mula becomes 
