Chromosome Aberrations in Two Haploid Derivatives of Sorghum

During the study of haploid progenies of a grain Sorghum variety Tx 403 two aberrant plants with 21 chromosomes were located. In one of the derivatives the extra chromosome formed a chain of five in a proportion of the cell analysed at diakinesis. This evidence suggested that the extra chromosome to be interchanged one, and the plant a tertiary trisomic. The second derivative appeared to be primary trisomic with a translocation involving the nucleolar chromosomes. Cytological evidence confirms the existence of many duplicate segments in the haploid complement of the grain Sorghum studied, and that some of them at least were located in subterminal or terminal regions of chromosomes.