Scientists Discover Pair of Genes that Strengthens Wheat’s Defense Against Powdery Mildew

Scientists have identified a pair of resistance genes in wild emmer wheat that could help protect cultivated varieties from powdery mildew, a major fungal disease affecting global wheat yields. The study emphasized that two adjacent NLR proteins, PmWR183-NLR1 and PmWR183-NLR2, must work together to confer immunity.

The team used advanced techniques, including map-based cloning, long-read genome sequencing, and CRISPR-Cas9, to uncover how PmWR183 functions. Unlike most known resistance genes, PmWR183 depends on the cooperation of two NLR proteins that physically interact to trigger the plant's immune response. Researchers found that PmWR183-NLR2 shows high diversity in its sequence, possibly reflecting a long evolutionary battle between wheat and its pathogens.

Notably, PmWR183 provides strong resistance at the adult stage of plant growth but limited protection in seedlings. Tests confirmed that this stage-dependent resistance is linked to changing expression levels of the two NLR genes as the plant matures. The researchers suggest that increasing PmWR183-NLR2 activity could extend protection earlier in development and help create wheat varieties that resist disease throughout their life cycle.

For more information, read the information from Nature.