UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 306 
Centribution from the Bureau of Plant Industry 
WM. A. TAYLOR, Chief 
Washington, D. C. PROFESSIONAL PAPER. October 15, 1915 
SOME EFFECTS OF SELECTION ON THE PRODUCTION OF 
ALKALOIDS IN BELLADONNA. 
By A. F. SIEVERS, 
Chemical Biologist, Drug-Plant and Poisonous-Plant Investigations. 
CONTENTS. 
Page. \ Page. 
Aa ROUUCTIONG 2). Gees casket cet 1 | Second-generation plants from cross-pollina- 
Selection of typical plants..........---.----- 2 LO TA Seen nan sensei bene cL My aimealey eee Sees 11 
Method of controlling pollination...--.....-- 2 | Reproduction of selected plants from cuttings 18 
First-generation plants from cross-pollinated Conclusions ee ee arctea sii 19 
TERED) s oes Oe SB ace ais ees i aa 3 
Comparison of first-generation plants from 
cross-pollinated and close-pollinated parents 6 
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. 
Atropa 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 
make a general study of the plant with regard to individual variation 
5931°—Bull. 306—15—1 
