In this study, we investigated the interplay between nitrogen nutrition and the pectin degradation dynamics during Arabidopsis and Botrytis interaction. Our findings revealed that infected detached leaves from nitrogen-sufficient plants released more pectin lyase (PNL)-derived oligogalacturonides compared to nitrogen-deficient ones. We then focused on BcPNL1, the most highly expressed Botrytis PNL upon infection. Using mutant strains lacking BcPNL1, we observed reduced pathogenicity, a delay in germination and a lag in triggering the plant defense response. Additionally, in nitrogen-sufficient detached leaves, the elevated expression of jasmonic acid repressor genes observed upon infection with the wild-type strain was abolished with the mutants. These results linked the increased production of BcPNL-derived products to the increased expression of jasmonic acid repressor genes, contributing partially to the higher susceptibility of nitrogen-sufficient detached leaves. These findings could lay the foundation for new strategies aimed at reconciling both crop resistance to pathogens and the improvement of nitrogen nutrition.
© 2025. The Author(s).