RELATIONSHIPS BETWEEN GROWTH RATES AND NUCLEIC ACID CONTENTS IN THE ROOTS OF INBRED LINES OF CORN

Abstract

W oodstock , L owell W., and F olke S kooc . (U. Wisconsin, Madison.) Relationships between growth rates and nucleic acid contents in the roots of inbred lines of corn. Amer. Jour. Bot. 47(9) : 713–716. Illus. 1960.—A study has been made of the rates of elongation and nucleic acid contents of the roots of inbred lines of Zea mays , var. W‐158, A‐374B, W‐58, W‐28, 8A, and W‐148. A direct proportionality was found between the ribosenucleic acid contents (μg./root) of the apical 3 or 6 mm. of the roots (roughly equivalent to their growing tips) and their rates of elongation. This strict, quantitative relationship to growth rate appears to be specific for RNA; it was not found for DNA, and it was independent of the size of the root. A detailed study of one line (W‐58) has shown, furthermore, that the ribosenucleic acid content in the root tip decreases with time in proportion to the decrease in the growth rate of the root.