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MISSOURI AGR. EXP. STA. RESEARCH BULLETIN 49 



These three varieties, which gave almost equal yields in rows 

 protected from competition, differed decidedly in their yields in ad- 

 jacent rows. Although Kherson outyielded Fulghum 4 per cent in 

 plots protected from competition, its yield was 30 per cent less than 

 that of Fulghum in single rows not protected from competition. 



Extreme effects of competition were shown in very numerous 

 cases in the tests of Kherson and Red Rustproof strains in 1921. An 

 example from this plot is the following: 



The extreme advantage of the Kherson strain in competition with 

 the Red Rustproof, increasing its margin of superiority from 59 per 

 cent to 198 per cent, is particularly striking. Probably even more 

 significant is the effect of competition between the two Red Rustproof 

 strains, resulting in the conversion of a 23 per cent loss to a 19 per 

 cent gain. 



All of the cases cited above are taken from plots in which the 

 rows ran east and west. Some examples of varietal competition from 

 tests in rows running north and south are the following: 



In the barley variety test, the variety Featherston 1118 occurred 

 between Red River 973 and Oderbrucker (the check variety). The 

 average yields of these three varieties in the three series were as follows : 



