Root-Tip Smear Method for Difficult Material

Abstract

A technic is outlined for the preparation of difficult material for the study of chromosome number and morphology in root-tip smears. The chief objective is to obtain polar views of the metaphase plates rather than equatorial views. To achieve this end it is recommended that fresh root-tips be cut free-hand into thin cross sections. The important features are: thin freehand cross sectioning of the fresh root-tips; fixing in Belling's iron aceto-carmine solution; maceration for 2–5 minutes in 50% HCl in 95% alcohol; and mounting in “Diaphane.”