Despite its commercial importance, lisianthus has lagged behind other ornamental crops in genetic improvement. Conventional breeding via F1 hybridization cannot precisely target key traits, while transgenic methods have struggled with low efficiency and poor reproducibility since the first transformation attempts in 1996. Flower-dipping methods later improved efficiency but remained limited, and CRISPR-Cas9 editing had only been demonstrated in protoplasts—not in whole plants. Based on these challenges, a reliable regeneration and transformation system enabling stable genome editing in whole plants has been urgently needed.
On June 10, 2026, researchers from the Floriculture Research Institute, Yunnan Academy of Agricultural Sciences, and Yunnan University published (DOI: 10.1093/hr/uhag197) their findings in Horticulture Research. The team established a robust Agrobacterium-mediated transformation platform based on somatic embryogenesis, achieving 100% editing efficiency in regenerated plantlets and successfully producing albino and green knockout lines targeting the EgPDS gene.
The breakthrough centers on a somatic embryogenesis system developed from cotyledon and hypocotyl explants. After approximately 30 days on callus induction medium containing 2,4-D, golden embryogenic calli formed and were transferred to differentiation medium. Using a RUBY marker-assisted transformation protocol, the researchers optimized Agrobacterium infection conditions and selection regimes to obtain hygromycin-resistant somatic embryos within two months. They designed multiple single-guide RNAs targeting EgPDS, a gene involved in pigment synthesis, and tested two CRISPR-Cas9 vector systems. The pCAMBIA1300-pYAO:Cas9 construct yielded 100% editing efficiency among PCR-positive plantlets, with mutations including single-nucleotide insertions, deletions, substitutions, and large-fragment deletions occurring at the target site. The newer AtU6-Diko vector produced abundant transgenic plantlets, with albino plants showing biallelic mutations while green plants retained one wild-type allele—demonstrating clear genotype-phenotype correlation and confirming reliable editing outcomes.
The authors explained the significance: “For decades, lisianthus breeding has been stuck with conventional methods that cannot precisely modify key traits. Our system finally breaks that barrier—we can now edit the genome of this major cut flower with high efficiency and predictability. We were particularly excited to see the clear correlation between mutation type and phenotype in the EgPDS lines; when both alleles were edited, the plants turned white, but plants with one wild-type copy stayed green. This tells us the system works exactly as designed.”
This platform provides breeders with a precise tool for molecular design breeding in lisianthus. The ability to knock out target genes efficiently accelerates the creation of elite germplasm with enhanced ornamental traits. Beyond flower color, the system can be adapted to modify flower morphology, floral scent, and stress tolerance, potentially reducing breeding timelines from years to months. As a proof-of-concept for other hard-to-transform ornamental species, this work could catalyze the adoption of gene editing across the floriculture industry, enabling sustainable, market-responsive cultivar development in a sector that has seen few genetically improved commercial varieties to date.
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References
DOI
10.1093/hr/uhag197
Original Source URL
https://doi.org/10.1093/hr/uhag197
Funding information
National Natural Science Foundation of China (32260781); Joint Project of Agricultural Basic Research of Yunnan Province—Key Project (202301BD070001-147); Yunnan Xingdian Talents—Special Selection Project for High-level Scientific and Technological Talents and Innovation Teams—Team Specific Project (202505AS350021); Yunnan Xingdian Talents—Youth Special Project (XDYC-QNRC-2022-0731).
About Horticulture Research
Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2023. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.