A NEW HETEROCHROMATIN BANDING-PATTERN REVEALED BY MODIFIED HKG BANDING TECHNIQUE IN MAIZE CHROMOSOMES

A new heterochromatin banding pattern for maize root tip chromosomes w as revealed by a modified HKG- (HCl-KOH-Giemsa) banding technique. Com parison of this pattern with that obtained by the C-banding technique showed that the two techniques stain different types of heterochromati n. The HKG-banding technique stains both centromeric and intercalary h eterochromatin, whereas the C-banding technique reveals only knob hete rochromatin. The presence of an HKG intercalary band adjacent to the k nob suggests a more complex constitution for the heterochromatic block of the knob.