FACTORS FOR YIELD AND QUALITY OF SPRING WHEAT 
59 
The data show that the heading period in one year is correlated 
with that in another year to a high positive degree both at the same 
station and at different stations. The average coefficient of 0.548 
may be considered very important. The correlation between F 2 
plants in 1923 and F 3 strains in 1924 at Bozeman illustrates the 
nature of the inheritance, and the data are given in Table 53. 
Table 53. — Correlation of heading period between F 2 plants and F s strains in 
Marquis-Hard Federation wheat crosses grown at Bozeman, Mont., in 1928 and 
1924 
Dates of heading, 1924 
Dates of heading, July, 1923 
14 
16 
18 
20 
22 
24 
26 
Total 
July 3 
1 
15 
16 
5 
1 
1 
15 
22 
22 
11 
1 
2 
July 4 . 
9 
22 
24 
20 
8 
1 
39 
July 5.... 
5 
3 
7 
4 
1 
1 
2 
1 
2 
66 
July 6 
56 
July?.. 
40 
July 8 
1 
_____ 
16 
July 9. 
3 
July 10 
1 
1 
July 11 
1 
1 
Total 
38 
73 
84 20 fi 
2 
1 
224 
r=0.505±0.034. 
Significant positive correlations were obtained between heading 
period and ripening period. The average correlation of 0.400 is 
important, since the characters are independent in chance of occur- 
ence but dependent in degrees of effect. 
Significant negative correlations were obtained between heading 
period and fruiting period. The average correlation of —0.276 may 
he considered of some importance, although not so high as might 
he expected of characters dependent in chance of occurrence and with 
partial association. The correlation between the two characters 
in F 2 plants grown at Bozeman in 1923 is representative of the 
average results, and the data are given in Table 54. 
Table 54. — Correlation between heading period and fruiting period in F2 plants of 
Marquis-Hard Federation wheat crosses grown at Bozeman, Mont., in 1923 
Heading period 
Fruiting period (days) 
35 
38 
41 
44 
47 
50 
53 
Total 
July 14 
6 
30 
58 
14 
2 
4 
14 
48 
47 
33 
8 
1 
1 
11 
72 
88 
12 
3 
2 
25 
47 
22 
5 
2 
2 
3 
3 
58 
July 16.- 
7 
10 
1 
207 
July 18 
228 
July 20 __ 
1 
66 
July22._ 
15 
July 24. 
7 
July 26 
1 
2 
Total 
1 
19 
114 
152 188 
101 
8 
583 
r=-0.249±0. 
