The effect of gamma radiation on subsequent germination of pollen.<p>
                                          
Chiscon, J. A.  <p>
 
Plants from line 206 of L.  Pimpinellifolium were subjected to gamma
irradiation at Brookhaven National Laboratory.  Plants were placed at varying
distances from the Cobalt source for 3.5 hours. Pollen was taken from new
flowers daily for 7 days and germinated in a sucrose solution as described in
an above report.<p>
<pre>

             Days Following Irradiation
Radiation
Dosage       1     2     3     4      5      5     6     7
                                  (8 am) (4 Pm)
________________________________________________________________
                      Percentage of Pollen 
                      Germination
                      ________________________
Control   92.3  91.3  92.0  96.0   82.4   86.1  85.6  98.1
1500 r.   93.7  87.6  87.1  94.0   ----   ----  89.3  69.5
2400 r.   84.1  88.7  87.6  95.2   75.4   15.2  29.0  29.8
4725 r.   87.0  89.1  85.4  92.3   49.1   22.4   0.0  27.3
6125 r.   ----  74.3  70.9  74.9    8.5    8.8   0.0  ----
</pre>

Germination fell markedly during the 5th day following irradiation.  Lack of
new flowers prevented the experiment from being continued past the 7th day.
Percentages are based on counts exceeding 200 grains.  Pollen was considered
germinated if the length of the tube exceeded the diameter of the grain. The
drop in germination after five days may be due to radiation damage during the
first mitotic division following meiosis in the formation of the male
gametophyte.<p>

<!--GH_SEARCH-->
<!--GH_END-->