Vernalization and Photoperiodism — 60 — A Symposium 



meristems, as altered by the photoperiod, would seem to be highly desirable. 

 Here we deal with the second most crucial problem of photoperiodism — the 

 induction of sexual reproduction. Perhaps a less complicated approach to 

 solution of the mechanism of floral induction would be by the use of tem- 

 perature as the external modifying factor, for it appears to act more di- 

 rectly on the terminal tissues. 



While these and other fundamental questions should, and eventually 

 will, be answered in studies of photoperiodism, further advances should be 

 made in the application of the phenomenon to various phases of plant cul- 

 ture and related problems. 



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