AUTHOR=Bryant Nathan , Zhang Jin , Feng Kai , Shu Mengjun , Ployet Raphael , Chen Jin-Gui , Muchero Wellington , Yoo Chang Geun , Tschaplinski Timothy J. , Pu Yunqiao , Ragauskas Arthur J. 

TITLE=Novel candidate genes for lignin structure identified through genome-wide association study of naturally varying Populus trichocarpa

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1153113

DOI=10.3389/fpls.2023.1153113

ISSN=1664-462X

ABSTRACT=<p><italic>Populus</italic> is a promising lignocellulosic feedstock for biofuels and bioproducts. However, the cell wall biopolymer lignin is a major barrier in conversion of biomass to biofuels. To investigate the variability and underlying genetic basis of the complex structure of lignin, a population of 409 three-year-old, naturally varying <italic>Populus trichocarpa</italic> genotypes were characterized by heteronuclear single quantum coherence (HSQC) nuclear magnetic resonance (NMR). A subsequent genome-wide association study (GWAS) was conducted using approximately 8.3 million single nucleotide polymorphisms (SNPs), which identified 756 genes that were significantly associated (−log<sub>10</sub>(<italic>p</italic>-value)&gt;6) with at least one lignin phenotype. Several promising candidate genes were identified, many of which have not previously been reported to be associated with lignin or cell wall biosynthesis. These results provide a resource for gaining insights into the molecular mechanisms of lignin biosynthesis and new targets for future genetic improvement in poplar.</p>