Genetically modified flowering potted plants with reduced ethylene sensitivity
H. Mibus, S. Sriskandarajah and M. Serek
ISHS Acta Horticulturae 847:75-80. 2009.
2009
บทคัดย่อ
Genetic modification has proved to be an effective way in controlling ethylene synthesis and perception. Use of the mutant ethylene receptor gene, etr1-1, from Arabidopsis seems most promising, especially when it is expressed under the control of a flower specific promoter.
In order to introduce the etr1-1 mutant gene in ornamental plant species we established effective regeneration and transformation systems for a range of popular potted plants including Campanula, Kalanchoë, Rhipsalidopsis and two orchid species Oncidium and Odontoglossum. Fertile transgenic adult plants of Campanula carpatica Jacq. and Kalanchoë blossfeldiana Poeln. were obtained by Agrobacterium tumefaciens-mediated transformation. The construct used for transformation contained etr1-1 gene under the control of the petal specific fbp1-promoter from petunia. Flowering T0 lines were tested for their ethylene sensitivity in 2 µl L-1 ethylene. The flowers on control (non transgenic) Kalanchoë and Campanula plants wilted within 2 and 3 days, respectively. The best transgenic line of Campanula flowered up to 27 days in ethylene, while the best Kalanchoë line had most of the flowers open for longer than 10 days of continuous ethylene exposure. T1 progenies of both species showed stable inheritance and expression of etr1-1, which make them useful for future breeding.
Before the ethylene insensitive plants can be commercially available, several issues have to be solved. Use of nptII for selection may cause implication by registration for commercial use, especially in European countries. Furthermore, molecular analysis indicated unwished expression of etr1-1 in leaves or roots, which in some cases correlated with lower ability of rooting of cuttings. Use of flower specific promoters from the species of interest can be recommended to solve the problem.