Relationships between Sphaerulina musiva Infection and the Populus Microbiome and Metabolome
Nicholas C. Dove, Alyssa A. Carrell, Nancy L. Engle, Dawn M. Klingeman, Miguel Rodriguez, Toni Wahl, Timothy J. Tschaplinski,
Wellington Muchero, Christopher W. Schadt, Melissa A. Cregger
18 March 2022, mSystems; https://doi.org/10.1128/msystems.00120-22
Pathogenic fungal infections in plants may, in some cases, lead to downstream systematic impacts on the plant metabolome and microbiome that may either alleviate or exacerbate the effects of the fungal pathogen. While Sphaerulina musiva is a well-characterized fungal pathogen which infects Populus tree species, an important wood fiber and biofuel feedstock, little is known about its systematic effects on the metabolome and microbiome of Populus. Here, we investigated the metabolome of Populus trichocarpa and Populus deltoides leaves and roots and the microbiome of the leaf and root endospheres, phylloplane, and rhizosphere to understand the systematic impacts of S. musiva abundance and infection on Populus species in a common garden field setting. We found that S. musiva is indeed present in both P. deltoides and P. trichocarpa, but S. musiva abundance was not statistically related to stem canker onset. We also found that the leaf and root metabolomes significantly differ between the two Populus species and that certain leaf metabolites, particularly the phenolic glycosides salirepin and salireposide, are diminished in canker-infected P. trichocarpa trees compared to their uninfected counterparts. Furthermore, we found significant associations between the metabolome, S. musiva abundance, and microbiome composition and α-diversity, particularly in P. trichocarpa leaves. Our results show that S. musiva colonizes both resistant and susceptible hosts and that the effects of S. musiva on susceptible trees are not confined to the site of canker infection.
Dove NC, Carrell AA, Engle NL, Klingeman DM, Rodriguez M, Wahl T, Tschaplinski TJ, Muchero W, Schadt CW, Cregger MA. Relationships between Sphaerulina musiva Infection and the Populus Microbiome and Metabolome. mSystems. 2022; Ahead of Print. doi.org/10.1128/msystems.00120-22