Effects of plant growth regulator, auxin polar transport inhibitors on somatic embryogenesis and CmSERK gene expression in Cattleya maxima (Lindl.)

The somatic embryogenesis is commonly used for rapid propagation of species of interest hard to reproduce, like orchids. The induction of somatic embryogenesis requires the establishment of a peculiar genetic expression pattern in the presence of the suitable environmental conditions and a favorable hormonal background, which can be obtained providing synthetic plant growth regulators. We tested several combinations of plant growth regulators in different illumination conditions on leaf explants of Cattleya maxima. The most efficient production of embryos was achieved with exogenous cytokinin (thidiazuron) in dark conditions at the cut end of the leaf. The expression of CmSERK gene was higher in the presence of cytokinins. The effects of the different treatments are discussed.