Use of High Performance Liquid Chromatography for the Determination of Endogenous Hormone Levels in Solanum tuberosum L. Subjected to Carbon Dioxide Enrichment of the Root Zone.

Changes in cytokinin, auxin, and abscisic acid levels were determined by high performance liquid chromatography following CO(2) enrichment of the root zone. Both trans zeatin and zeatin riboside significantly decreased in the roots 6 days after treatment with CO(2). In the leaves zeatin riboside increased whereas trans zeatin showed no significant difference from the control. Indoleacetic acid in the leaves increased dramatically for 6 days following CO(2) treatment; however, indoleacetic acid levels in the roots increased slightly after 2 days and remained higher than the control. Abscisic acid increased shortly after CO(2) treatments; after 6 days this difference was no longer evident.