54 H. K. HAYES 



Hayes and Johnson (1939) in Minnesota studied the relation between the 

 characters of 110 inbred lines of maize and their performance in top crosses. 

 The characters studied in selfed lines in replicated yield trials are given in 

 Table 3.4. 



All possible correlations were made between the individual characters of 

 the inbreds and of these characters and the yield of grain of top crosses. The 



TABLE 3.4 



CHARACTERS OF 110 INBRED LINES IN 

 CORN CORRELATED WITH INBRED- 

 VARIETY YIELDING ABILITY 



1. Date silked 7. Stalk diameter 



2. Plant height 8. Total brace roots 



3. Ear height 9. Tassel index 



4. Leaf area 10. Pollen yield 



5. Pulling resistance 11. Grain yield 



6. Root volume 12. Ear length 



TABLE 3.5 



TOT.\L CORRELATIONS BETWEEN CHARACTERS OF 110 INBREDS, 

 LABELED 1 TO 12, AND YIELDING ABILITY OF INBRED- 

 VARIETY CROSSES DESIGNATED AS 15 



Significant value of r for P of .05 = 0.19. 

 Significant value of ;■ for P of .01 = 0.25. 



characters, in general, were those that were considered to evaluate the in- 

 breds in developmental vigor. 



The total correlations between characters are summarized in Table 3.5. 

 Most correlations were significant at the 5 per cent or 1 per cent point ex- 

 cept the relation between ear length and other characters of the inbreds. All 

 relationships between the characters of the inbreds, including grain yield, and 

 the yield of top crosses were significant at the 1 per cent point except for 

 tassel index of the inbreds, and that was significant at the 5 per cent point. 

 The multiple correlation coefficient of 0.67 indicated that under the condi- 

 tions of the experiment about 45 per cent of the variability of inbred-variety 



