Vernalization and Photoperiodism — 100 — A Symposium 



rather than upon an increase in knowledge of how to regulate the environ- 

 ment to induce flowering. 



Anatomical changes in the stems (sampled at the fourth internode from 

 the tip) have been observed to be consistently related to the entrance of a 

 plant into the reproductive state. After-affects which are characteristic 

 of some plants (with a systemic blossoming habit) and not typical of others 

 (with a terminal blossoming habit) are associated with cambial activity. In 

 fact, this difference in blossoming habits suggests a possible difTerence in 

 the transport systems of different species. 



A study of the relation of the anatomical development of a plant to 

 sexual reproduction indicates that an item which is urgently needed for a 

 solution of why plants blossom would be the extraction or discovery of a 

 substance which would produce maturation phenomena when applied to or 

 introduced into a non-blossoming plant, in contrast to the producing of 

 proliferation phenomena by presently known phytohormones. 



References: — 



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