The wheat genome is considered to be difficult to edit using the CRISPR-Cas9 system due to its hexaploid genome, and scientists have tried incorporating the system to the plant using protoplasts and particle bombardment but obtained poor results. 

Scientists from The John Bingham Laboratory in UK used Agrobacterium-mediated transformation to incorporate the gene-editing system in wheat and targeted the TaPDS gene. Results showed 11 to 17 percent efficiency for single-gene targeting and five percent efficiency for tri-genome targeting. The scientists concluded that transgene-free wheat lines edited for a specific gene can be ideally developed within 36 weeks using this method.

For more information, read the article in BMC Plant Biology.