112 Clyde E. Leighty 



Correlations 



Coming now to the correlations that exist in these several varieties, 

 it is seen in Table 5 that seven correlation coefficients for each variety 

 have been determined. These are grouped in the table in such a way 

 that the coefficients for each variety are given under a single heading 

 showing the characters correlated. 



TABLE 5. Correlations, Series 1200, 1219, 1238, 1257.* Varieties 



Average yield of culm per plant, in decigrams — Average height of plant, in centimeters 



1200 r = .866 ± .010 1238 r = .889 ± .008 



1219 r= .859 ± .010 1257 r= .875 ± .009 



Average yield of culm per plant, in decigrams — Average number of kernels per culm of plant 



1200 r = .959 ± .003 12.38 r = .985 ± .001 



1219 r= .934 ± .005 1257 r= .965 ± .003 



Average yield of culm per plant, in decigrams — Average number of spikelets per culm of plant 



1200 r == .961 ± .003 1238 r= .985 ± .001 



1219 r= .916 ± .006 1257 r= .954 =h .003 



Average yield of culm per plant, in decigrams — Average weight of straw per culm of plant, 



in decigrams 



1200 r= .818 ± .013 1238 r= .944 ± .004 



1219 r= .933 d= .005 1257 r= .925 ± .006 



Average yield of culm per plant, in decigrams — Average weight of kernels per plant, in 



milligrams 



1200 r= .686 ± .021 1238 r= .596 ± .025 



1219 r= .539 ± .028 1257 r= .563 ± .027 



Average weight of kernels per plant, in milligrams — Average height of plant, in centimeters 



1200 r= .654 ± .022 1238 r= .575 ± .026 



1219 r-- .553 ± .027 1257 r= .577 ± .026 



Average weight of kernels per plant, in milligrams — Average number of kernels per culm 



of plant 



1200 r= .524 ± .028 1238 r= .494 ± .029 



1219 r= .340± .034 1257 r= .415 ± .032 



* 1200, Great American 

 1219, Early Champion 

 1238, Welcome 

 1257, Sixty Day 



For average yield of culm per plant correlated with average height of 

 plant (Figs. 86 to 89), the coefficients are seen to be nearly equal for the 

 several varieties. The highest, .889 ± .008 for series 1238, is but .030 ± 

 .013 higher than the lowest, .859 ± .010 for series 1219. The extreme 

 difference is a little more than twice its probable error. 



