2018 ASHS Annual Conference

Junhui Zhou and Zhongchi Liu, Dept. of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742

The clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 system is an effective genome editing tool for plant and animal genomes. However, there are still few reports on the successful application of CRISPR-Cas9 to horticultural plants, especially with regard to germline transmission of targeted mutations. We will describe our efforts in developing CRISPR-Cas9 vectors and its high efficiency genome editing in the wild strawberry Fragaria vesca. Specifically, we will show results of successful application of CRISPR-Cas9 to mutate the auxin biosynthesis gene TAA1 and Auxin Response Factor 8 (ARF8) and the resulting phenotype. To test germline transmission of the edited mutations and new mutations induced in the next generation, we also analyzed the progeny of the primary (T0) transgenic plants carrying the CRISPR construct. We found normal germline transmission of the mutations induced in the parent generation as well as high efficiency induction of new mutations, including large deletions between the two PAM sites within the same gene. The results indicate that our CRISPR vectors can be used to edit the wild strawberry genome at a high efficiency and open up exciting opportunities for engineering strawberry and related horticultural crops to improve traits of economic importance.