A Cytogenetical Study of a Reciprocal Translocation in Zea

Abstract

A reciprocal translocation between chromosomes 2 and 5 was found in untreated material. Of the 2 new chromosomes formed, the one with its insertion point from 2 had no knobs, the one with its insertion point from 5 had a knob in each arm, one from each chromosome. This reciprocal translocation led to 50% ovule and pollen abortion and was designated "semi-sterile 4." A ring of 4 chromosomes was found at diakinesis. Detailed genetical evidence is given to show the points of translocation and the order of genes within the newly formed chromosomes,.