Abstract
Several physiologically-active regulating substances were used to investigage their role on the respiratory climacteric and ripening of sugar apple fruits (Annona squamuosa L.).
Both indoleacetic acid (IAA) and 1-aminocyclopropane-1-carboxylic acid (ACC) enhanced the softening and electrolyte leakage of the fruits. Respiration of IAA-treated fruits were also enhanced.
Two ethylene biosynthesis inhibitors, aminoethoxyvinylglycine (AVG) and 2, 4-dinitrophenol (DNP), were administered to the fruits to examine the physiological effects. Softening was delayed, the increase of total soluble solids (TSS) approached but did not reach as high a level as the control and electrolyte leakage was greater than in the control.
Cycloheximide (CHI) treatment caused the fruits to remain hard anti unripe during storage, and to have lower TSS content and electrolyte leakage than the normal ones.
Increase in endogenous IAA content of the fruits during storage at 20°C preceded ethylene evolution.
