Characterization of European forage maize lines for stover composition and associations with polymorphisms within O-methyltransferase genes

Cell wall components, such as lignin, cellulose, and hemicelluloses, play an important role in the conversion efficiency of corn stover into ethanol. Understanding the molecular basis of cell wall formation is fundamental for marker assisted selection to develop lines more suitable for ethanol production. In this study, we evaluated a set of 40 European forage maize lines for cellulose, lignin, total hemicellulose, glucuronoarabinoxylan (GAX), and monosaccharides, such as arabinose (ara), xylose (xyl), and glucuronic acid (GlcA). The most significant correlations were observed between hemicelluloses and GAX (0.9), and hemicelluloses and cellulose (−0.81). Cell wall digestibility (CWD, estimated by digestible neutral detergent fiber, DNDF) was negatively correlated with Xyl (−0.34). The association analysis between the evaluated traits and polymorphisms within ten “lignin” genes revealed significant associations between polymorphisms within CCoAOMT1, CCoAOMT2, 4CL2 and C4H, and cellulose/xyl, cellulose, cellulose, and GclA, respectively. None of the QTPs identified in this study corresponded to previously reported CWD QTPs.

► We studied genetic associations between sequence polymorphism within lignin genes and cell wall components from maize stover.
► Eight polymorphisms within four lignin genes were associated with xylose, cellulose, and GlcA.
► These polymorphisms did not correspond to previously reported QTPs associated with cell wall digestibility.