|SREL Reprint #0091|
Interactions of Gamma Radiation and Other Environmental
Stresses Upon Pine Seeds and Seedlings
Frank McCormick and Robert E. McJunkin
This is a pilot study to determine the effects of ionizing radiation upon
slash (Pinus elliottii) and longleaf (Pinus palustris)
pine seeds and seedlings, and to identify environmental factors which modify
species radiation sensitivities. Seeds
and seedlings were exposed to several radiation doses and then grown in a
variety of post-irradiation environments, some of which included high
temperature, low moisture and low light. Per
cent germination, growth, physiological tolerances, and survival usually varied
inversely with the radiation dose received.
Germination rates, drought tolerances, and growth under low light
intensities were increased by doses in the range of 100-500 R.
Slash seeds were more sensitive than longleaf seeds but the order of
seedling sensitivity was reversed. Results
of this study indicate that the condition of the organism and the nature of the
environment prior to and following irradiation must be rigorously defined in
order to evaluate radiation effects.
SREL Reprint #0091
McCormick, J.F. and R.E. McJunkin. 1965. Interactions
of gamma radiation and other environmental stresses upon pine
seeds and seedlings. Health Physics 11:1643-1652