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Title: Host genotype controls ecological change in the leaf fungal microbiome
Leaf fungal microbiomes can be fundamental drivers of host plant success, as they contain pathogens that devastate crop plants and taxa that enhance nutrient uptake, discourage herbivory, and antagonize pathogens. We measured leaf fungal diversity with amplicon sequencing across an entire growing season in a diversity panel of switchgrass ( Panicum virgatum ). We also sampled a replicated subset of genotypes across 3 additional sites to compare the importance of time, space, ecology, and genetics. We found a strong successional pattern in the microbiome shaped both by host genetics and environmental factors. Further, we used genome-wide association (GWA) mapping and RNA sequencing to show that 3 cysteine-rich receptor-like kinases (crRLKs) were linked to a genetic locus associated with microbiome structure. We confirmed GWAS results in an independent set of genotypes for both the internal transcribed spacer (ITS) and large subunit (LSU) ribosomal DNA markers. Fungal pathogens were central to microbial covariance networks, and genotypes susceptible to pathogens differed in their expression of the 3 crRLKs, suggesting that host immune genes are a principal means of controlling the entire leaf microbiome.  more » « less
Award ID(s):
1832042
PAR ID:
10433332
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Editor(s):
Dong, Xinnian
Date Published:
Journal Name:
PLOS Biology
Volume:
20
Issue:
8
ISSN:
1545-7885
Page Range / eLocation ID:
e3001681
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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