Highly Efficient Agrobacterium-mediated Stable Transformation of Cymbidium goeringii

Oriental orchids possess great potential in the consumer market because of their diverse leaf and flower patterns and enchanting fragrance. Nevertheless, their long growth period, stringent growth environment requirements, low germination rates, and limited transformation methods pose significant obstacles to genetic improvement. To improve the regeneration efficiency of oriental orchids and enhance their transformation efficiency, the solid–liquid oscillation–solid alternating cultivation mode was used to efficiently obtain stable transformants of Cymbidium orchids in this study. The results showed that within approximately 2 months, the regeneration rate of C. goeringii derived from protocorm-like bodies reached a remarkable 77.30% with this method. The transformation efficiency of C. goeringii achieved through polymerase chain reaction amplification was 18.66% when inoculated with Agrobacterium LBA4404, and the positive transformation rate reached 75.03%. This experimental result was further validated by β-glucuronidase staining and green fluorescent protein fluorescence detection. This methodology significantly increased the positive transformation rate and shortened the regeneration period of C. goeringii . Furthermore, this cultivation mode was successfully implemented for C. faberi and C. ensifolium . Therefore, the solid–liquid oscillation–solid alternating cultivation mode provides a technical basis for efficient transformation, which will promote the rapid development of genetically improved oriental orchids.