Influence of sucrose feeding on sugar metabolism and invertase activity in cut Dendrobium flowers

Abstract

Importance of the work: The invertase enzyme is important for sugar metabolism; however, there is little information available on invertase activity in Dendrobium flowers.
Objectives: To investigate the changes in acid invertase activity and sugars in cut Dendrobium flowers held in a vase solution.
Materials & Methods: Inflorescences of Dendrobium cv. Khao Sanan were held either in distilled water or in solutions containing a combination of germicidal compounds and sucrose. The invertase activity and concentrations of sucrose, glucose and fructose in floral buds and open florets were determined.
Results: Cell wall invertase activity increased at bud opening; however, there was no increase in vacuolar invertase activity. Sucrose treatment increased cell wall invertase activity in the perianth but not in the column and did not increase vacuolar invertase activities in either the perianth or the column.
Main finding: Cell wall invertase activity was higher than vacuolar invertase activity for all flower developmental stages. Sucrose treatment stimulated the accumulation of hexoses in the floral buds and increased cell wall invertase activity in the perianth.