Corn Investigations 
39 
actually occurs under our ordinary field conditions is negligible 
and that no material advantage results from selecting seed from 
detasseled rows and thereby assuring the prevention of all self- 
fertilization. 
Incidentally the yields were determined separately for the 
detasseled and not detasseled rows in the seed plat for the pur- 
pose of determining the immediate effect of detasseling upon the 
current crop. As an average for the eight years (Table 13), 
the plats from which all of the tassels were removed yielded 
13.6 bushels per acre as compared with 12.9 bushels for the 
normal corn. The tassels were removed at their first appearance 
by means of an upward pull which disjointed them without 
molesting the leaves. 
Table 13. — Immediate effect of detasseling upon the current grain 
yield of the detasseled, plants. (Nebraska White Prize.) 
Eight years , 1912-1017 and 1920-1921. 
Yield of grain per acre 
Treatment 
1912 
1913 
1914 
1915 
1916 
1917 
1920 
1921 
Average 
Bu. 
Bu. 
Bu. 
| Bu. 
Bu. 
Bu. 
* Bu. 
Bu. 
Bu. 
(1) 
(2) 
(3) 
(4) 
(5) 
(6) 
(7) 
(8) 
(9) 
(10) 
Detasseled 
51.6 
10.9 
38.2 
68.1 
39.9 
41.5 
43.4 
55.1 
43.6 
Not detasseled 
54.4 
1G.1 
38.0 
71.7 
35.0 
37.9 
43.6 
52.3 
42.9 
Number of plats 
averaged 
8 
18 
19 
8 
8 
- 8 
8 
8 
ELEMENTAL STRAINS IN CORN AND THEIR HYBRIDIZATION 
SIGNIFICANCE OF ELEMENTAL STRAINS 
An ordinary commercial variety of corn is very complex in 
its inheritance. We may think of such a variety as having for 
its basis a large number of elemental strains or “pure lines” 
which differ from each other in some more or less important 
structural or physiological characteristic. These elemental 
strains do not occur in the variety as a mere mechanical mix- 
ture, but rather as natural hybrids due to chance wind pollina- 
tion. The characteristics transmitted by these elemental strains 
to their hybrid offspring is in accordance with the principles of 
Mendelian inheritance. They are represented in the germ plasm 
(chromosomes of the reproductive cells) in the form of Men- 
delian factors or units of inheritance. All inheritance is trans- 
mitted thru the chromosomes, of which field corn is believed to 
