The transgenic Dendrobium ‘Sonia’ BOM 17 containing an antisense ACO gene demonstrated normal growth with prolonged vase life

The growth of four transgenic Dendrobium Sonia ‘BOM 17’ lines possessing antisense ACC oxidase gene, were evaluated using two-year-old transgenic orchid lines grown in a biosafety greenhouse.
The parameters investigated, in relation to ACO included, 1-aminocyclopropane-1-carboxylic acid (ACC) enzyme activity, ACC oxidase (ACO) and ethylene production in the leaves and inflorescence, and the vase life of the inflorescence.
The results revealed that the leaves of the transgenic orchid contained 0.15 pmol g^‑1 FW of ACC while the 4 transgenic lines had ACC levels ranging from 0.1 to 0.15 pmol g^‑1 FW. The ACO enzyme activity in the leaves of the transgenic orchids was found to be in the range of 0.004 to 0.0065 pL C₂H₄ mg^‑1 protein h^‑1, which was lower than those of the non-transgenic lines (0.008), a reduction of 18.75-50%. The transgenic lines produced 0.036 to 0.08 nL C₂H₄ g^‑1 h^‑1 of ethylene, which was lower than that of the control line at 0.104 nL C₂H₄ g^‑1 h^‑1, a reduction of 23.08-68.36%. Similar patterns were also observed in the inflorescence.
When compared to the non-transgenic line, the ACO activity was reduced to 34.48-53.45% of the control and the ethylene production was not only decreased in the transgenic lines but its production was delayed.
The transgenic lines had a 29-57% longer vase life than did the non-transgenic lines.

III International Orchid Symposium

S. Chanprame, P. Sornchai, S. Reanboon, W. Kongkuna, W. Imsabai

orchid, transgenic, ACO, antisense, flower senescence

https://doi.org/10.17660/ActaHortic.2019.1262.17