UNITED STATES DEPARTMENT OF AGRICULTURE 



BULLETIN No. 306 % 



■S&? m< &~ri* 



Contribution from the Bureau of Plant Industry 

 WM. A. TAYLOR, Chief 



jV£?"^Wt» 



Washington, D. C. 



PROFESSIONAL PAPER. 



October 15, 1915 



SOME EFFECTS OF SELECTION ON THE PRODUCTION OF 

 ALKALOIDS IN BELLADONNA. 



By A. F. Sieveks, 

 Chemical Biologist, Drug-Plant and Poisonous-Plant Investigations. 



CONTENTS. 



Introduction 1 



Selection of typical plants 2 



Method of controlling pollination 2 



First-generation plants from cross-pollinated 



parents 3 



Comparison of first-generation plants from 



cross-pollinated and close-pollinated parents 6 



Second-generation plants from cross-pollina- 

 tion 11 



Reproduction of selected plants from cuttings 18 



Conclusions 19 



INTRODUCTION. 



The improvement of many of our important agricultural crops has 

 been brought about by means of plant selection and breeding, and 

 similar methods are being extended to various other fields of plant 

 production in the hope of achieving similar results. 



With a few exceptions, the growing of medicinal plants is still in 

 its early stages, and it is a much-debated question whether these 

 plants when cultivated lose any of their therapeutic properties; but 

 with the constantly diminishing supply of many of our important 

 native drug plants cultivation becomes more and more imperative. 

 Also, the quality of some of the drugs on the market has deteriorated 

 to such an extent that improvement is much to be desired, and it is 

 hoped that this may be accomplished through the methods employed 

 by the plant breeder. 



Atropn belladonna is an important mydriatic drug, the supply of 

 which has been of such inferior quality in recent years that the 

 Office of Drug-Plant and Poisonous-Plant Investigations has been 

 conducting experiments for some time with special reference to in- 

 creasing the alkaloidal content of the plant. The first step was to 

 in.ike a general study of the plant with regard to individual variation 



6931"— Bull. 30fi— 16 1 



