AUTHOR=Zhang Xiaoyu , Low Yee Chen , Lawton Michael A. , Simon James E. , Di Rong 

TITLE=CRISPR-Editing of Sweet Basil (Ocimum basilicum L.) Homoserine Kinase Gene for Improved Downy Mildew Disease Resistance

JOURNAL=Frontiers in Genome Editing

VOLUME=3

YEAR=2021

URL=https://www.frontiersin.org/journals/genome-editing/articles/10.3389/fgeed.2021.629769

DOI=10.3389/fgeed.2021.629769

ISSN=2673-3439

ABSTRACT=<p>Sweet basil (<italic>Ocimum basilicum</italic> L.) downy mildew disease (DM) caused by <italic>Peronospora belbahrii</italic> is a worldwide threat to the basil industry due to the lack of natural genetic resistance in sweet basil germplasm collections. In this study, we used CRISPR-gene editing to modify the sweet basil DM susceptibility gene <italic>homoserine kinase</italic> (<italic>ObHSK</italic>). Gene-edited plants challenged with <italic>P. belbahrii</italic> displayed a significantly reduced susceptibility to DM, based on phenotypic disease indices and on <italic>in planta</italic> pathogen load. These results suggest that <italic>ObHSK</italic> plays a role in conditioning DM susceptibility, similar to that observed for the <italic>AtHSK</italic> gene in Arabidopsis. These results demonstrate the utility of CRISPR-gene editing in enhancing DM resistance and contributing to sweet basil breeding programs.</p>