AECD-3446(App. )
layers
ii
From the work of Jacobsen and Overstreet (17), it is known that fission
products are absorbed onto roots but are not translocated in significant quanti-~ties to other parts of the plant.
Therefore the external radiation which was
received was predominatly beta radiation from the contaminated surface layer of
the soil.
After careful consideration of all possible causal agents it seems highly
probable that radiation is the cause of the tumorous growths on Ipomoea.
How-
ever, it must be pointed out that we have not attempted to experimentally induce
such tumors and that no radiation induced plant tumors have been previously
reported in the literature to our knowledge.
We feel justified,
however,
in con-
cluding thet the tumorous tissue herein described most nearly resembles radiation
damaged tissue.
Acknowledgment. We wish to acknowledge with gratitude the suggestions made by Dr. E. J.
Kraus, Department of Horticulture, Oregon State College, Corvallis, Oregon.
This work has been supported in part by funds contributed by the AEC under
subcontract to W-28-09h-eng 33, now AT(45-1)5h0, Applied Fisheries Laboratory.
DOF ARCH