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Surveying the genus Aconitum from the viewpoint of the chemist one is 

 confronted with over 300 presumed valid species of aconites spread through- 

 out the northern hemisphere. One outstanding problem is the taxonomy 

 of the genus. The genus was monographed, as a whole in 1826 by Reichen- 

 bach. It is hoped that the future monographer will be duly cognizant of the 

 cytogenetical implications that exist in this group. From a center of dis- 

 tribution that would seem to be the Altai Mountains the plants are spread 

 throughout the northern mountainous regions with a series of diploid, tetra- 

 ploid, hexaploid, and octoploid plants. Many triploids are found either as 

 accidental hybrids or as products of the plant hybridizer. 



When the chemical constituents of the various polyploidy series are 

 compared it has been found that the diploid aconites are for the most part 

 non-toxic. The diploid Aconitum noveboracense of the Beaverkill region is 

 non-toxic. Triploid and tetraploid aconites contain various modifications of 

 the aconitine molecule and are among the most powerful poisons known. 

 Yet the Indian aconite, A. palmatum, a hexaploid, is non-toxic. The octo- 

 ploids have not been studied chemically and their toxicity is unknown. The 

 cytogenetical factors underlying the chemical constitution of the different 

 aconites is not known. 



The tuberous roots of the diploids are relatively small, while the triploid, 

 tetraploid and octoploid tubers of the blue flowered aconites are from eight 

 to ten times the size of the diploid types. The blooming period of the aconites 

 follows in the order of their chromosome number. In the triploid, Sparks 

 Aconite, it seems certain that the plant arose from diploid parents, or at least 

 one parent was a diploid while the other may have been a tetraploid. This 

 would indicate that increasing the chromosome number in this aconite has 

 resulted in the production of chemical substances which have marked toxicity. 

 Many of the triploid have been found to be sterile plants and thus may only 

 be propagated as clones. This is a desirable quality as it may be used as a 

 means of standardizing the type of plant that produces a particular pr.oduct. 



In two aconites studied it has been found that in addition to the normal 

 chromosome complex found in the root tip, sectors have been found 

 with the double number of this chromosome complex. One triploid aconite 

 had a sector with the hexaploid chromosome complex, while a diploid 

 species have shown sectors with the tetraploid number of chromosomes. 

 Since these chromosome duplications occurred in nature it may point to the 

 origin of the polyploid series that exists in the genus Aconitimi. Experiments 

 have been carried out which indicate that one may, through the use of colchi- 

 cine, induce chromosome duplication in the aconites. These problems are 

 now being carried out with the idea of developing toxic chemical substances 

 from diploid plants which are non-toxic. 



Respectfully submitted, 



Clyde Chandler 

 Recording Secretary 



