Studies on Aged Seeds III: Sensitivity of Aged Wheat Seeds to X-Radiation

Abstract

Wheat (Triticum vulgare var. Baart, 2n = 42) seeds of different ages were X-rayed at different dosages and the frequency of chromosome aberrations and rate of germination were recorded. For the cytological study 1-, 3-, 13-, and 17-year-old seed were X-rayed at 1000r, 2000r, 3000r, and 4000r. For the germination study 2-, 5-, and 15-year-old seed wore X-rayed at 5,000r, 10,000r, 15,000r, and 20,000r. Both studies showed that with an increase in age the radio-sensitivity also increased. Within a given dose the germinability decreased and the frequency of dicentric chromosome bridges and acentric fragments increased as the seeds increased in age. The measured radio-sensitivity of the chromosomes in the aged seeds may be due, in a large part, to chemical compounds which are produced in the aged seeds through decomposition of the seed reserves.