Am.  Jour.  Pharm. 
June,  19 17. 
Breeding  for  Atropine. 
255 
against  quantity  to  quality  against  quantity.  Stating  the  case  in  a 
more  simple  way  it  may  be  said  that  financial  success  in  the  cultiva- 
tion of  drug  plants  depends  upon  the  possibility  of  increasing  the 
alkaloid  content  of  these  plants  by  plant  breeding  methods. 
The  object  of  this  paper  is  to  point  out  to  breeders  who  are  in- 
terested in  this  field  of  work  the  opportunity  which  these  plants  offer 
for  selective  methods  of  improvement.  The  resulting  improvement 
from  research  work  in  this  direction  not  only  will  afford  the  satis- 
faction which  is  coincident  with  accomplishment,  but  will  provide 
raw  materials  of  uniform  and  high  quality  to  the  exacting  profes- 
sions of  medicine  and  pharmacy.  This  surely  then  is  a  worthy  field 
for  experimental  effort.  It  at  once  becomes  evident  that  the  work 
of  increasing  alkaloids  in  a  plant  differs  from  that  of  increasing  size, 
changing  color  or  form.  The  investigator  is  dealing  with  unseen 
characters. 
Little  Hybridization  Done 
Hybridizing  drug  plants  has  been  attempted  by  several  workers 
and  under  varying  conditions  but  in  general  little  result  has  been 
gotten  from  this  method.  There  may  be  exceptions  to  this  state- 
ment, such  as  cinchona;2  but  especially  with  plants  of  the  temperate 
zone,  the  great  majority  of  crossing  experiments  have  resulted  only 
in  a  chaotic  jumble  of  characters  without  meaning.  This  is  to  be 
expected  when  we  keep  in  mind  the  class  of  plants  with  which  we 
are  dealing. 
The  most  serious  effort  then  must  be  through  selective  methods, 
but  here  again  certain  difficulties  at  once  arise.  Since  the  characters 
with  which  we  are  working  are  unseen,  the  number  of  individuals 
that  can  be  placed  under  observation  is  therefore  limited,  and  in  turn 
the  chances  of  success  are  proportionately  reduced. 
In  establishing  a  system  of  selection  of  belladonna3  (Atropa 
Belladonna)  at  the  Mulford  Drug  Gardens,  the  effort  was  made  to 
overcome  this  difficulty  by  establishing  a  correlation  between  some 
apparent  physical  character  and  alkaloidal  content.    If  such  a  corre- 
2  The  South  American  cinchona  tree,  from  the  bark  of  which  quinine  is 
secured,  has  been  improved  by  breeders  in  Java,  who  have  selected  the  best  of 
many  natural  hybrids,  and  propagated  them  asexually.  This  is  usually  re- 
ferred to  as  the  only  drug  plant  which  has  been  improved  through  hybridizing ; 
but  so  far  as  I  am  aware,  there  is  no  record  of  really  scientific  breeding  having 
been  done  with  it. 
3  For  an  outline  of  some  similar  work  with  belladonna  and  other  plants, 
see  "Breeding  Medicinal  Plants,"  by  F.A.Miller.  American  Breeders'  Maga- 
zine, IV,  pp.  193-201. 
