The Respiratory Metabolism of Strelitzia juncea Ait. Seeds: The Effect of Dormancy Release through Oxygen Incubation of the Seeds on the Activity of Glucose-6-Phosphate Dehydrogenase and 6-Phosphogluconate Dehydrogenase

Incubation of Strelitzia juncea seeds in an oxygen atmosphereresulted in an increase in the G6PDH activity of crude embryoextracts on day one, while radicle protrusion started on dayfive. Similarly, 6PGDH activity increased over the first 4 dof incubation in oxygen. The ratio of 6PGDH/G6PDH was 3.0<x < 3.7 regardless of treatment or incubation period. Supplying oxygen per se to dormant seed and studying its effecton the activity of the two key pentose phosphate (PP) pathwayenzymes, appear to support Roberts' hypothesis that oxygen shortagerestricts PP pathway activity in dormant seeds. Key words: Dormancy, pentose phosphate pathway, Strelitzia juncea