Nuclear DNA, nuclear area and nuclear dry mass in thirteen species of Crotalaria (Angiospermae, Leguminosae)

Abstract

Estimations on nuclear DNA content, nuclear area and nuclear dry mass were made on 13 species of Crotalaria, with the help of Vicker's M 85 microdensitometer and Vicker's interferometer. Highly significant differences for all three characters were found between species. DNA density (DNA/area) increased with increase in DNA content. The cultivated species, C. juncea had a lower DNA density relative to its DNA content.—Nuclear DNA made only a small fraction of nuclear dry mass (1∶15). Although total dry mass and non-nucleolar nuclear dry mass showed significant regression on DNA content, the nucleolar dry mass gave a much wider scatter, indicating that nucleolar mass is not equally dependent on nuclear DNA content.