05/04/2026
May the Force (of gene editing) Be With You (as you fight powdery mildew)...
In this month's newsletter, Dr. Laurent Deluc and Dr. Satyanarayana Gouthu share exciting advancements getting us closer to gene editing control of powdery mildew.
Here's a synopsis:
For decades, MLO (Mildew locus O) genes have been recognized as susceptibility factors for powdery mildew across multiple crop species, but impairing their function to achieve resistance has often come with unintended developmental trade-offs. A recent study from Oregon State University, currently under peer review, used CRISPR-based multiplex editing in the microvine model to dissect the combinatorial effects of four grapevine clade V MLO genes—VitviMLO3, 4, 13, and 17—on powdery mildew susceptibility.
The findings reveal unequal and partially redundant contributions among these genes, with VitviMLO17 playing the most prominent role, followed by VitviMLO13, while VitviMLO3 and 4 contribute primarily to later stages of fungal sporulation. Notably, a quadruple-knockout line with incomplete editing achieved strong resistance without significant developmental penalties, suggesting that residual MLO activity may be sufficient to maintain essential physiological functions.
The authors conclude that durable resistance will require precise editing strategies that disrupt susceptibility functions while preserving the gene family's roles in normal growth—or, alternatively, RNA interference-based approaches for season-long management.
Read more: https://owri.oregonstate.edu/article/gene-editing-can-contribute-powdery-mildew-control-strategies
