Mutation Rate Increased by Aging Seeds as Shown by Pollen Abortion

Abstract

Gene mutations of a common type and a large proportion of chromosomal mutations in Datura stramonium are indicated by pollen abortion. Storage of dry seeds up to 10 yrs. increased the rates of pollen abortion mutations about in proportion to the age of the seeds. In 2 flower samples 7.9% mutations were found from seeds over 5 yrs. old, 2.7% from seeds less than 5 yrs. old, and 0.6% from fresh seeds. Most of these mutations occurred in sectors of the plants, as did similar mutations induced by radiation treatments of dry seeds. Neither unusual radiation effects nor differential rates of germination seemed to account for the increased mutation rates obtained from aged seeds.