CORN growers' association. 



93 



be selected, and, from these 200 cars, tlic 40 ears which are most suitable 

 as seed for the particular kind of corn which it is desired to breed should 

 be selected, either by mechanical examination of sections of kernels, which 

 aiiybody can make, or by chemical analysis, or by a combination of these 

 two methods. In our own work we now commonly select by physical 

 inspection or measurement the 200 ears ; then, from these 200 ears, we 

 select by mechanical examination of sections of kernels the best 50 or 

 100 ears, and from this lot we finally select by chemical analysis the 

 best 20 to 40 seed ears for planting. This combination of methods 

 effects a very satisfactory seed selection and requires only one-half as 

 much chemical work as would be required if the method of chemical 

 analysis alone were employed. 



Table 2 shows very fairly the degree of seed improvement which 

 may be accomplished by these dift"erent methods of selection, when breed- 

 ing to change only the protein content of corn. 



It may be stated that equally satisfactory results may be obtained 

 ill chemical selection by mechanical examination for securing seed ears 

 of high or low oil content. For example, the writer has selected by 

 mechanical examination, from a lot of 272 ears of corn, 18 ears for high 

 oil content which averaged 5.24 per cent of oil ; and, from the same lot 

 of corn, 30 ears were "selected for low oil content which averaged 4.13 

 per cent oil, making an average difference of i.ii per cent of oil. 



TABLE 2-SOME FAIR ILLUSTRATIONS OF ACTUAL RESULTS OBTAINED IN SE- 

 LECTION OF SEED CORN. 



(Protein, average per cent.) 



* Average protein content of ten field rows of Burr's White after four years' breeding for 

 high protein. 



t Originally from same stock of Burr's White as preceding, but bred four years for low 

 protein. 



■ * Two lots of 42 ears each selected from the same lot of 200 ears for two breeding plots, 

 high protein and low protein, the seed for which is selected by physical Inspection and me- 

 chanical examination but without chemical analysis of individual ears. 



