Re: Hormesis - Theory and Observation

["willy valdivia-granda" <willy_valdivia@ndsu.nodak.edu>]

The hormetic effect also has been found for us in plants. Here is part of
the manuscript, further research wil confirm this experiments.

Study of the radiosensitivity of two inbred lines of sunflower (Helianthus
annuus L.) to fast neutrons and gamma rays.
Willy A. Valdivia-Granda and Deckard, E. 
Plant Sciences Department
North Dakota State University

Abstract: 

The objective of this study was evaluate the response of sunflower inbred
lines to different doses of fast neutrons and gamma rays. The achenes of two
sunflower inbred lines 2416 and 3162 (confectionery and oil types,
respectively) were exposed to fast neutrons doses comprehending 2, 5, 10,
20, 40, 100, and 120 Gy and gamma rays to 80, 160, 320, 400, 560, 620 and
700 Gy. Irradiated achenes were germinated in petri dishes in complete
darkness for a period of 8 days at 25o C. Evaluation of the germination rate
indicated that the line 2416 was more radiosensitive than 3162 to fast
neutrons. When irradiated with fast neutron dosage of 2 Gy, the germination
rates were increased by 44.2% and 74.5% for the lines 2416 and 3162,
respectively. The same dose increased the number of emerged plants in the
field for the inbred 2416 by 23.6 %. No differences were found between
inbreds irradiated with gamma rays at doses ranging from 80 to 700 Gy during
germination assays. However, stimulatory effect in plant emergence by 36 %
was observed in the inbred 3162 irradiated with 80 Gy. Pants from achenes
irradiated with 2 and 5 Gy growing in the greenhouse were taller and showed
early flowering at least of 5 days. Finally, despite that the stimulatory
effect was observed during germination, field and greenhouse evaluations,
was not possible repeat this experiment since the same sunflower achenes
were not available. Remaining question is if this phenomenon induces DNA
damage and mutations, and in subsequent generations the same stimulatory
effect is observed. 


Any comments?

Willy Valdivia

--On Thursday, May 11, 2000, 2:11 AM -0500 Muckerheide
<muckerheide@mediaone.net> wrote: 

> GlennACarlson@aol.com wrote:
>> 
>> While considering the alleged hormetic effect of exposure to radon, the
>> relative absence of data supporting a similar alleged effect for
radiation
>> exposure from other sources, and the truism (almost cliche) that
"radiation
> 


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