AUTHOR=Zhang Yang , Liu Yong , Gan Zhimeng , Du Wei , Ai Xiaoyan , Zhu Wei , Wang Huiliang , Wang Furong , Gong Linzhong , He Huaping 

TITLE=Transcriptomic and sugar metabolic analysis reveals molecular mechanisms of peach gummosis in response to Neofusicoccum parvum infection

JOURNAL=Frontiers in Plant Science

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2024.1478055

DOI=10.3389/fpls.2024.1478055

ISSN=1664-462X

ABSTRACT=<p>Peach gummosis, a devastating disease caused by <italic>Neofusicoccum parvum</italic>, significantly shortens peach tree lifespan and reduces the yield of peach trees. Despite its impact, the molecular mechanism underlying this disease remains largely unexplored. In this study, we used RNA-seq, sugar metabolism measurements, and an integrated transcriptional and metabolomic analysis to uncover the molecular events driving peach gummosis. Our results revealed that <italic>N. parvum</italic> infection drastically altered the transcripts of cell wall degradation-related genes, the log<sub>2</sub>Fold change in the transcript level of <italic>Prupe.1G088900</italic> encoding xyloglucan endotransglycosylase decreased 2.6-fold, while <italic>Prupe.6G075100</italic> encoding expansin increased by 2.58-fold at 12 hpi under <italic>N. parvum</italic> stress. Additionally, sugar content analysis revealed an increase in maltose, sucrose, L-rhamnose, and inositol levels in the early stages of infection, while D-galactose, D-glucose, D-fructose consistently declined as gummosis progressed. Key genes related to cell wall degradation and starch degradation, as well as UDP-sugar biosynthesis, were significantly upregulated in response to <italic>N. parvum</italic>. These findings suggest that <italic>N. parvum</italic> manipulates cell wall degradation and UDP-sugar-related genes to invade peach shoot cells, ultimately triggering gum secretion. Furthermore, weighted gene co-expression network analysis (WGCNA) identified two transcription factors, <italic>ERF027</italic> and <italic>bZIP9</italic>, as central regulators in the downregulated and upregulated modules, respectively. Overall, this study enhances our understanding of the physiological and molecular responses of peach trees to <italic>N. parvum</italic> infection and provide valuable insights into the mechanisms of peach defense against biotic stresses.</p>