Intragenic Canola Germplasms with Clubroot Resistance Gene Rcr1 Developed with a New CRISPR/Cas9-based Vector System
Citation
Hao H, Zhang Y and Yu F 2023. Intragenic Canola Germplasms with Clubroot Resistance Gene Rcr1 Developed with a New CRISPR/Cas9-based Vector System. PAG 30. San Diego, USA, 2023. (Poster)
Résumé en langage clair
Breeding for resistance to crop diseases is of crucial importance for global food security and societal sustainability. However, general biotechnologies like transgenesis or genome editing are not ideal for serving this purpose, while novel cisgenic/intragenic crops could perfectly fit into this niche. In this study, after cloning and functional verification of clubroot resistance (CR) gene Rcr1, we re-devised a CRISPR/Cas9-based vector system and a streamlined workflow to serve the purpose of intragenic breeding in canola (Brassica napus L.) for the first time, and novel intragenic canola germplasms with potent resistance to clubroot disease were successfully developed. The new system features auto-excision to remove undesired genetic traces from the final product, and no off-target mutations were detectable in the B. napus background. With the high performance of this new vector system, novel intragenic germplasms could be developed within 2 generations, which could significantly shorten the breeding time compared to traditional introgression while achieving comparable breeding results. This new vector system and workflow could be easily applied to other crops where Agrobacterium-mediated transformation is available. We anticipate that it can also serve as a powerful tool for other similar applications in the bright future of precision molecular plant breeding. In this study, we also confirmed that CR genes Rcr1, Rcr2, Rcr4, CRa from B. rapa vegetables and the CR gene from B. napus oilseed rape cultivar ‘Mendel’ on chromosome A03 were identical.
Résumé
Breeding for resistance to crop diseases is of crucial importance for global food security and societal sustainability. However, general biotechnologies like transgenesis or genome editing are not ideal for serving this purpose, while novel cisgenic/intragenic crops could perfectly fit into this niche. In this study, after cloning and functional verification of clubroot resistance (CR) gene Rcr1, we re-devised a CRISPR/Cas9-based vector system and a streamlined workflow to serve the purpose of intragenic breeding in canola (Brassica napus L.) for the first time, and novel intragenic canola germplasms with potent resistance to clubroot disease were successfully developed. The new system features auto-excision to remove undesired genetic traces from the final product, and no off-target mutations were detectable in the B. napus background. With the high performance of this new vector system, novel intragenic germplasms could be developed within 2 generations, which could significantly shorten the breeding time compared to traditional introgression while achieving comparable breeding results. This new vector system and workflow could be easily applied to other crops where Agrobacterium-mediated transformation is available. We anticipate that it can also serve as a powerful tool for other similar applications in the bright future of precision molecular plant breeding. In this study, we also confirmed that CR genes Rcr1, Rcr2, Rcr4, CRa from B. rapa vegetables and the CR gene from B. napus oilseed rape cultivar ‘Mendel’ on chromosome A03 were identical.