Activity and gene expression of ethylene biosynthetic enzymes of 'Irwin' mango during fruit ripening.
Soe T. T., Koshio K., Takahashi H., Iwahori S., Sugaya S., Gemma H.
Author Affiliation: Department of International, Agricultural Development, Tokyo University of Agriculture, 156-8502, Japan.
: 535-540
Abstract : The present investigation was undertaken to study the effect of storage temperature in controlling ethylene production through the activity and gene expres-sion of ethylene biosynthetic enzymes of 'Irwin' mango during fruit storage. Ethylene evolution and activities of ethylene biosynthetic enzymes, 1-aminocyclo-propane-1-carboxylic acid (ACC) synthase and ACC oxidase were investigated using fruit harvested at commercial maturity and stored at 20 and 13°C, together with gene expression of these enzymes. Just after harvest respiration was high although it soon decreased. A climacteric peak was observed after 6 days at 20°C or 8 days at 13°C. Peak ethylene evolution occurred after 2 days at 20°C or 12 days at 13°C although ethylene evolution steadily increased after 4 days at 13°C. Highest activities of ACC synthase and ACC oxidase were recorded after 2 at 20°C and 8 days at 13°C, coinciding with ethylene climacteric peaks. Expression of both ACC synthase and ACC oxidase genes was higher for fruit stored at 13°C than at 20°C. The dynamism of ethylene biosynthetic enzyme activity and gene expression of those enzymes indicated enhanced effectiveness at lower storage temperatures.