THE STRESS RESPONSES OF INFLORESCENCES OF DENDROBIUM ‘BIG WHITE JUMBO’ DURING MA STORAGE

The aim of this study was to describe the effects of packaging on the antioxidative systems in Dendrobium inflorescences, ‘Big White Jumbo’. Inflorescences were harvested at commercial maturity at an export company orchard.
The stem of individual inflorescences were re-cut and inserted into a plastic tube containing distilled water, then packed in polypropylene bags or active packaging and kept at 13°C for 5 days.
Activities of catalase (CAT), peroxidase (POD), ACC oxidase (ACO), concentrations of malondialdehyde, proline and water were determined in florets.
It was found that active packaging increased CAT and POD activities compared to packaging in polypropylene.
The activities of CAT and POD in opened flowers were higher than flowers at the bud stage.
Conversely, flower buds had higher ACO activity than opened flowers.
The column of flowers had higher activities of POD and ACO than the petals.
Malondialdehyde decreased slightly after storage at 13°C for 5 days in both packaging materials, but there were no significant differences.
Neither polypropylene film nor active packaging affected water content in both buds and opened flowers.
Proline in flowers packed in active packaging was slightly higher than flowers stored in polypropylene film, but the accumulation of proline was lower in opened flowers.
The display life of ‘Big White Jumbo’ inflorescences stored in polypropylene film was 10 days, while that of inflorescences stored in active packaging was 6 days.
It is proposed that the induction of CAT and POD or a decrease in ACO activity precede the onset of senescence of Dendrobium inflorescences ‘Big White Jumbo’.

VI International Postharvest Symposium

S. Manuwong, A. Uthairatanakij, P. Jitareerat, S. Kanlayanarat, K. Obsuwan, A. Fuongfuchat

ACC oxidase, catalase, peroxidase, proline content

https://doi.org/10.17660/ActaHortic.2010.877.53