Differential Fluorescent Bandings and Isozyme Assay to Distinguish Three Varieties in Zinnia elegans L. (Compositae)

Abstract

The orange, yellow and pink flowered varieties of Zinnia elegans L. possessed 2n=24 metacentric chromosomes of each. The orcein-stained interphase nuclei and prophase chromosomes revealed the existence of facultative heterochromatin in the orange and yellow flowered varieties. Four CMA-positive terminal bands were observed in the orange and yellow flowered varieties whereas only two CMA-positive terminal bands appeared in the pink flowered variety. In all these varieties, a prominent CMA-positive band of same size (1.2 μm) was found. Only one DAPI-positive band appeared in the orange flowered variety. A bright DAPI-positive band was found at the centromeric region in each chromosome of the yellow flowered variety. No DAPI band was observed in the pink flowered variety. The activity of peroxidase was similar in all these varieties. However, the three varieties showed different activities for esterase and acid phosphatase. Isozyme analysis indicates that activities of esterase and acid phosphatase were less in the orange variety than the other two. Thus, application of fluorescent bandings together with isozyme analysis was able to distinguish the intervarietal diversification in Z. elegans.