Three seed types: bean (Phaseolus vulgaris), corn (Zea mays) and radish (Raphanus sativus) were flown in a high altitude weather balloon into the mid-stratosphere to investigate the effects of high altitude radiation on germination success and seedling growth. After recovering and planting the seeds, the bean seeds showed lower germination success with exposure to high altitude radiation, and consequently stunted seedling growth. Cord and radish seeds experienced a statistically significant positive effect on germination success form radiation exposure compared to control seeds, but negative effect on seedling growth. Overall, the field experiments presented here support laboratory studies that show radiation exposure on vegetable seeds has a mixed effect on the germination success and negative effect on seedling growth on investigated seed types.
Fong, B. N.; Newhouse, K. V.; Huss, M. J.; Roberts, E.; Kennon, J. T.; and Ali, H.
"Investigating the Effect of Stratospheric Radiation on Seed Germination and Growth,"
Journal of the Arkansas Academy of Science: Vol. 69
, Article 9.
Available at: http://scholarworks.uark.edu/jaas/vol69/iss1/9