The Use of Lacto-Propionic Orcein in Rapid Squash Methods for Chromosome Preparations

Abstract

A solution of 2 gm of natural orcein dissolved in 100 ml of a mixture of equal parts of lactic and propionic acids, and diluted to 45% with water, proved more effective than other stain fixatives for meiotic preparations from fresh pollen mother cells. When used after 5 min fixation in modified Carnoy's fixative (alcohol, acetic acid, chloroform, formalin; 10:2:2:1) and 5 min maceration in 1 N HC1 at 60° C, the same stain proved the most suitable for the rapid preparation of root-tip chromosomes for counting and for studying detailed morphology.