HYBRIDIZATION METHODS IN CORN BREEDING. 101 



well with the theory upon which he bases his suggestion. If the 

 "broad breeding" idea is taken as a basis and a new variety is brought 

 into the combination every year, it is plain that it must be done 

 blindly, since the influence which this new variety will have upon 

 either the quality or quantity of the crop cannot be known. However, 

 the method advocated by Mr. Williams, of the Ohio Agricultural 

 Experiment Station, would overcome to a certain extent the blindness 

 of this "introduction of new blood" by first testing its influence. 



In the method of Morrow and Gardner, which, as we have seen, 

 has been endorsed by East and Collins, involving the use of strains 

 that, according to my experiments, are already complexly hybrid, 

 there must be more or less resolution of characters in the resultant 

 cross-bred plants, since the crop would not consist of F x plants with 

 respect to all the numerous characters in which the two chosen parental 

 strains differed, but would be, with respect to many of them, the F 2 

 (second generation hybrid) in which splitting up of characters occurs. 

 The method which I described last year under the name of a "pure- 

 line method" is the only one yet suggested in which all the plants 

 in the resultant progeny would be first generation hybrids in regard 

 to all the qualities which served to distinguish the parents. This does 

 not prove, however, that my pure-line method is better than the 

 method of Morrow and Gardner. It may be true, as Dr. East says, 

 that the pure-line method is "more correct theoretically but less prac- 

 tical" than the method of Morrow and Gardner which he describes. 

 It is conceivable that the method of using highly developed strains 

 which have been produced by line-breeding and continual selection 

 of the best and most vigorous ears may produce such high yields when 

 crossed together that the expense and trouble of isolating pure 

 biotypes will not be justified; but such a conclusion can be properly 

 reached only as the result of extensive experimentation; and this 

 experimentation, if undertaken in earnest by our State experiment 

 stations, must result in the discovery of the best possible method for 

 the breeding of Indian corn. My anxiety is not for the success of the 

 pure-line method outlined by myself, but that serious experimentation 

 shall be undertaken by every station within the corn-growing region 

 for the purpose of discovering what is the best method. I feel quite 



c Williams, C. G., Corn Breeding and Registration. Report American Breeders 

 Association, 3 : 110-122, 1907. 



