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UNITED STATES DEPARTMENT OF AGRICULTURE 
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BULLETIN No. 971 
Contribution from the Bureau of Plant Industry 
WM. A. TAYLOR, Chief 
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Washington, D. C. 
PROFESSIONAL PAPER 
December 3, 1921 
INHERITANCE OF RAMOSE INFLORESCENCE IN 
MAIZE. 
By J. H. Kempton, Assistant in Crop Acclimatization. 
CONTENTS. 
Page. 
The ramose ear variation in maize__ 1 
Description of the parents 3 
First generation 4 
Second generation 5 
Correlation of the ear characters of 
the second generation 7 
Page. 
Third generation 8 
Fourth generation 9 
Discussion 13 
Conclusions 18 
Literature cited 20 
THE RAMOSE EAR VARIATION IN MAIZE. 
From the standpoint of the origin of the ear of maize, perhaps the 
most instructive variation is the ramose type of inflorescence discov- 
ered by Gernert (4) 1 in a strain of Learning Yellow Dent. In this 
variation the simple pistillate inflorescence is replaced by a com- 
pound structure which resembles somewhat the staminate inflores- 
cence. Practically all the grain is borne on branches, the central 
axis bearing seeds at the extreme apex only. (PL I; see also PL X.) 
The larger surface on which seeds may be borne increases the po- 
tential production, although the actual yield of grain is much less 
than on normal plants of the parental variety. A single ramose ear 
has been found to produce 4,700 pistils (PL II), while the production 
of one-quarter of that number would be unusual on an ear of the 
parental Learning variety. The failure to produce grain in quan- 
tity commensurate with the number of pistils seems to be due, at 
least in part, to the mechanical difficulty of exserting such a large 
number of pistils through the ends of the husks, although there 
doubtless are other restricting factors. 
Serial numbers in parentheses refer to " Literature cited " at the end of this bulletin. 
51551°— Bull. 971 — 1921 1 
