Strigolactone (SL) biosynthetic mutants have repeatedly been associated with reduced germination of parasitic Orobanchaceae in vitro. However, the extent to which this translates into field resistance has been poorly investigated.
Based on replicated field trials, we show that although the SL-deficient pea mutants rms1 and rms5 are more resistant to Orobanche crenata (Oc) than their wild-type background, they still experience substantial Oc parasitization. Accordingly, we find that the pea breeding line ROR12, which displays nearly complete field resistance to Oc, employs both SL-dependent and SL-independent resistance mechanisms, as resulting from genetic analysis and RNA-seq.
Overall, our findings highlight the need to explore pea breeding strategies that are independent of low SL exudation. It will also be particularly interesting to investigate whether these results apply to other legumes or crops affected by Orobanchaceae.
Read the full paper here: https://bmcplantbiol.biomedcentral.com/articles/10.1186/s12870-025-07296-x