Activities of glycolytic enzymes in leaves and roots of contrasting cultivars of sorghum during flooding

Activities of phosphofructokinase (PFK), fructose-1,6-bisphosphate aldolase (FBP aldolase) and pyruvate kinase (PK) increased progressively in the roots of flood-tolerant SSG-59-3 cultivar during flooding. In contrast, only a slight change in activities of PFK and FBP aldolase was discerned in the roots of flood-sensitive S-308 cultivar during initial stages of flooding followed by a decline in the activities of these enzymes. Although the activity of hexokinase (HK) was transientiv elevated in roots of both the cultivars during flooding, the magnitude of increase was much more in SSG-59-3 than in the S-308. In leaves of SSG-59-3, HK activity increased during 12 h of flooding whereas only a minor change occurred in the case of S-308. Flooding resulted in depressed activities of PFK and PK in leaves of S-308 but that in SSG-59-3 rose following imposition of waterlogged conditions. Activity of FBP aldolase in leaves of tolerant cultivar also showed a steady enhancement during flooding. The total and reducing sugars content decreased in leaves and roots of the S-308 during flooding but in SSG-59-3 the amount was more or less comparable to that in corresponding non-flooded plants.