Amount of DNA and Genotypic Differences in Hordeum

Abstract

The relative 4C nuclear DNA content in arbitrary units, in 16 different diploid (2n=14) species and varieties and two tetraploid (2n=28) species of Hordeum has been analysed with the aid of in situ Feulgen microphotometry with two wavelength method. In all the diploids, more or less same amount of DNA has been recorded and it is nearly double for the tetraploids. It has been suggested that the evolution of species and varieties of Hordeum has not been associated with marked differences in DNA content. This constancy in a widely distributed and cultivated genus reflects a strong selective advantage of this feature.