Changes in Buds and Seeds in Response to Chilling 105 



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DISCUSSION 



Dr. Torrey: Is it possible to say from your assays whether your in- 

 hibitor affects cell elongation or cell division in the embryos? You 

 gave evidence to suggest that the accelerator affected the acceleration 

 of cell enlargement in roots. Can you distinguish between the two 

 processes? 



Dr. Wareing: I am afraid not. We have looked at cell division 

 and cell extension at certain stages, but I am afraid I can't specifically 

 answer that question with regard to the promoter on root growth. 



Dr. Tukey: Dr. Wareing, you spoke about the inhibitor zone. This 

 is the endosperm, is it? [Yes.] There is a very interesting situation in 

 peach that falls right in line with what you are suggesting. 



Of course, the peach seed must be after-ripened before it will 

 germinate, but if the integuments are removed, the naked embryo 



