Experimental production of a new karyotype in Delphinium

Abstract

A new karyotype which is both viable and stable has been obtained in Delphinium following X-ray induced chromosomal rearrangements. It shows, on the whole, greater symmetry than the parental karyotype although one of the chromosome pairs was reduced to a minute size. The meiotic sequence in the structural heterozygote and the isolation of the homozygote having the altered karyotype in its progeny have been briefly described. The structural rearrangement has been found to be associated with a change in the growth habit of the plants, indicating a possible position effect.