34 



MISSOURI AGR. EXP. STA. RESEARCH BULLETIN 49 



the value of the variety on the left is greater. The figures ready for 

 correlation study will then appear as follows: 



The columns headed "competition data" show the relation of the 

 effect of competition to the yield, earliness, and height of the competing 

 varieties. For example, Michigan Amber was at a disadvantage of 20 

 per cent in competition with Fultz, though it was 22 per cent superior 

 in yield when protected from competition. It headed the same day, 

 matured one day later, and was one inch shorter. After correspond- 

 ing data had been prepared for all the 96 varieties in this test, correla- 

 tion tables with the coefficient of competition as subject and relative 

 yield, date of heading, date of maturity, and height as relative were 

 constructed. Correlations were determined similarly in the other tests. 

 One of these correlation tables is shown in figure 6. In general, merely 



o o 



00 O 



FIGURE 6. CORRELATION BETWEEN COEFFICIENT OF COMPETITION AND RELA- 

 TIVE YIELD, IN WHEAT VARIETY TEST 1920. 



r= +.582 .043. 



