PpMYB123-mediated proanthocyanidin accumulation alleviates bacterial spot disease in peach

Abstract

Bacterial spot (BS) disease significantly impairs vigor, fruit quality, and yield in peach trees. However, research on this disease remains limited. In this study, peach leaves and fruits were inoculated with the pathogen isolated from infected leaves, triggering a robust accumulation of proanthocyanidins (PA) in both tissues. Further investigation revealed that pathogen inoculation promoted PA accumulation by upregulating PpMYB123, which transactivated the core PA biosynthetic genes PpANR and PpLAR. Notably, the E3 ubiquitin ligase PpPUB23 negatively regulated PpMYB123. However, its transcript levels were significantly suppressed following inoculation, thereby stabilizing PpMYB123 and enhancing PA production. PA conferred dual protection by scavenging excess reactive oxygen species (ROS) and suppressing pathogen growth. Our findings provide molecular evidence for PA-mediated defense against BS disease in peach.

Acknowledgements

This project was supported by funds received from National Natural Science Foundation of China (32302497), the China Agriculture Research System (grant CARS-30) and the Wuhan Botanical Garden Scientific Research Support Project (E3559901).

Author contributions

J.-P.A. and L.Z. planned and designed the experiments. L.Z., D.A., Z.L. and M.L. performed the experiments. C.L. and Q.P. collected experiment samples. D.A., and Z.L. performed the sequence analysis. L.Z. wrote the paper. J.-P.A. and Y.H. revised the manuscript.

Data availability

All data can be found online in the main text and supporting information materials.

Conflicts of interest statement

The authors declare no competing interests.

Supplementary material

Supplementary material is available at Horticulture Research online.

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