The Genetic Nature of X-Ray Induced Changes in Pollen

Abstract

X-radiation of micro-spores of diploid spp. of Tradescantia shortly after meiosis increases variability in pollen grain length and % of aborted grains, indicating that size and viability are due in part to the genotype of the pollen itself. The effect is greater after treatment at 3[degree] than at 33[degree]. Similar radiation of autotetraploid spp. confirms this conclusion by failing to give similar results, since unaffected dominant alleles mask the recessive mutations. Statistical analysis in the pea, Pisum sativum, where 4 kinds of hybrid pollen are intermediate in size and more variable than either parent further confirms the theory of self determination of pollen size by a large number of genes.