115 



The rMPROVEMENT OP Medicinal Plants. 



By F. a. Miller. 



Certain suggestions were made before the last meeting of tlie Academy 

 for tlie possible improvement of valuable medicinal forms through the ap- 

 plication of breeding methods. 8ome of these suggestions have been car- 

 ried out during the past summer upon experiuH^iital plots of belladonna, 

 henbane, stramonium, digitalis and cannabis. The results, though only ten- 

 tative, are extremely encouraging, and indicate a means of obtaining not 

 only greater yields of the resulting drugs, but better and more reliable 

 medicinal products. 



Belladonna has sbcnvn great uniformity in morphological characters, 

 but considei'able variability in the percentage of alkaloids in selected 

 plants. In a comparatively small number this variation was found to be 

 over 50%, or from 0.52% to O.S7%c total alkoloids as found in the highest 

 and lowest yielding individuals. Much has been said concerning the varia- 

 tion in total alkaloids as influenced by various conditions. In fact some 

 experimental work has been done upon the influence of such factors as food 

 elements, light and shade, soils, meteorology, etc., upon the production of 

 alkoloids and oilier active principles. It now seems apparent, however, 

 that before such data can have any scientific bearing, or be utilized as a 

 means of following the influence of given factors, uniform strains of the 

 plants under investigation must first be obtained. This apparent neces- 

 sity is due to the wide variations \^'hich have been ftnuul to exist between 

 the individuals of a given group which have been grown under uniform 

 conditions. 



A group of individual plants varying over 50%: when grown under uni- 

 form ecological conditions cannot be expected to behave uniformly when 

 grown luider varied conditions. Differences no greater than 50% have been 

 reported as being due to certain external influences as affecting all plants 

 upon a given area, while according to I'ecent individual plant investiga- 

 tions, such an area might produce plants varying this luuch or more among 

 themselves, and representing at the same time any possible mixture with 

 reference to yield. It seems necessary, for this reason, to first obtain a 



