Factors affecting the sensitivity of barley seeds presoaked at two different temperatures to fission neutrons and 250 kvp X-rays

Barley seeds soaked in water for different periods (0,4,10,16,20,24,28,36 hr), at 1 and 270C have been irradiated with varying doses of X-rays and fission neutrons, and the height of seedlings has been measured after 7 days. The following conclusions have been drawn from these studies. A linear increase in damage with increasing absorbed energy of fission neutrons is observed. When the hydration temperature is 10C, the increased absorbed energy caused by the relative abundance of hydrogen and increased nuclear volume explains the increase in damage. When there is relatively high metabolic activity as in seeds presoaked at 270C, factors other than the increased hydrogen content and nuclear volume are involved. Greater sensitivity of presoaked seeds to X-rays is due to a number of factors of which the increased energy deposition per nucleus as a result of increased volume of nucleus is one. (author)