UNITED STATES DEPARTMENT OF AGRICULTURE 
DEPARTMENT BULLETIN No. 1164 
Washington, D. C. 
August JO. 1523 
SEGREGATION AND CORRELATION OF CHARACTERS IN AN 
UPLAND-EGYPTIAN COTTON HYBRID 
By 
THOMAS H. KEARNEY, Physiologist in Charge, Office of Alkali an .: Drought 
Rewtant Plant Investigations, Bureau of Plant Industry 
CONTENTS 
Page 
Introduction 1 
Aacestry *l Ibe hybrid 3 
Characters dislinjuisbinf the Ho'don and Pima varieties 4 
Ckiraders of the firs'-geeeratjon hybrid 6 
Definition of (he characters measured or graded 7 
Statistical eonrtanls of Ihe parental and of the Fi and Fs hybrid populations 11 
Frequency d : siributioas of the second generation ol the hybrid 15 
Meodelian segregation in the H:idon-Pima hybrid 21 
t)a!a of (he Ho don-Pima hybrid compared with erdeuee from other sources of Mendeliar segregation in 
cotton h/brids 27 
Evidence from F» ot segregation in the Holdon-Pima hybrid in characters not giving definite Mendetian 
ratios in Ft «, 33 
Extraparenta! characters in ¥■> of the Holdon-Pi.na Lybrid 39 
Sterility in Fs am. Ft of the Holdon-Pima hybrid 41 
Correlation of characters in F- of Ibe Holdon-Pima hybrid 44 
Practical sign>tt>aace of the results 50 
Summary 52 
Literature cited 56 
WASHINGTON 
GOVERNMENT PRINTING OFFICE 
1923 
