Ascorbic Acid in the Avena Coleoptile

Publisher Website
Google Scholar
Abstract
1. Ascorbic acid is present in considerable concentrations in Avena coleoptiles from etiolated seedlings. 2. On the basis of wet weight determinations, reduced ascorbic acid is present in higher concentrations in tips than in bases of coleoptiles, and oxidized ascorbic acid shows the reverse gradient of distribution. 3. The distribution of ascorbic acid in the coleoptile corresponds with the distribution of chlorophyll in plants grown in the light, but does not depend upon chlorophyll either for its presence or for its distribution in the coleoptiles of plants grown in the dark. 4. Light increases the concentration of ascorbic acid in the coleoptile, and aging decreases it. 5. Ascorbic acid is not present in the germinating seed, but is synthesized in the coleoptile from a precursor in the seed. 6. Reduced ascorbic acid is oxidized more by extracts from basal sections of coleoptiles than by extracts from apical sections. This destruction gradient corresponds with the destruction gradient of auxin in the coleoptile. 7. Ascorbic acid is not a cell elongation hormone like auxin, nor does it facilitate the action of auxin in the standard Avena or pea tests.

This publication has 0 references indexed in Scilit: