i 9 o THE POPULAR SCIENCE MONTHLY 



THE BOLE OF SELECTION IN PLANT BREEDING 1 



By Professor E. M. EAST 



HARVARD UNIVERSITY 



WHEN one attempts to give some idea of the principles and of the 

 methods and scope of plant breeding, the matter falls naturally 

 into two parts, the role of selection and the role of hybridization. This 

 is not because the subject is really thus separable, but because the meth- 

 ods in use fall into these categories. One must, of course, use selection 

 after hybridization, but there are a number of plants of great agricul- 

 tural value, in which either the flowers are too small for artificial cross- 

 ing or in which other reasons make it desirable to use simply selection 

 in their improvement. It is of these that this paper will treat. 



The particular work discussed has been selected because it will il- 

 lustrate certain principles, not because it is regarded as more important 

 than other work of like nature. The work of many quiet men who are 

 striving for the good of mankind by their efforts toward the improve- 

 ment of plants deserves to be mentioned, but unfortunately the limits 

 of a single paper are too narrow to discuss principles and to say much 

 about practise, and knowledge of the former should be made more 

 widespread in order that the latter may be appreciated. 



The non-botanical public can not be blamed if it receives compara- 

 tively worthless productions with greater acclaim than those of value 

 when the former obtain all the publicity and no voice is raised in pro- 

 test. Exploitations of new plant introductions of little value have 

 certainly been numerous in the past few years. Perhaps this has been 

 a public benefit, for it has increased the general interest in plant breed- 

 ing and has stimulated many laymen to study the subject in order to 

 be able to separate the wheat from the tares when dealing with new 

 varieties. It is strange, perhaps, with our reputation for always look- 

 ing for the dollar sign, that the new agricultural productions of great- 

 est economic value have always received less notoriety than the pro- 

 duction of horticultural novelties of limited use and small importance ; 

 yet such is the case. It is doubtful whether the production of a new 

 field corn that would increase the yield in the United States by ten 

 per cent, would obtain more than a passing notice from the press; yet 

 such an increase would add $100,000,000 per annum to the wealth of 



1 This paper is based on a series of poular lectures delivered at the Bussey 

 Institution of Harvard University April and May, 1910. A second paper will 

 follow. 



